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Labor is not passive. Your body and mind both need to be actively involved. That said, there are some ways...
Labor is not passive. Your body and mind both need to be actively involved. That said, there are some ways to prepare for the massive event that is labor and childbirth. 484x194-labor-prep.jpg Practice your kegels religiously. Squat and do a little pelvic tilt: To complete a pelvic tilt exercise, get down on all fours. Your knees and hands should be comfortably planted on the floor (preferably carpet). Arch your back slightly while inhaling. Your abdominal muscles should be contracted. Exhale and round your back while pulling your abs up. You can do this about 10 times a day to strengthen your core muscles. These core muscles are going to help you to effectively push your baby out into the world. It's good to make them strong. If you feel any pain stop right away. Practice sitting on a birthing ball: (Also known as an exercise ball). You can use this technique during labor to relieve pain and promote the opening of the pelvis which helps your baby to descend in the birth canal. You do need to practice before hand, because although sitting seems easy, sitting on a birth ball can be tricky if you've never done it. During labor is not the time to be trying new things; there will be quite enough new things going on. During pregnancy using a birthing ball has added benefits as it can really relieve back pain. You can sit on your ball instead of a chair to surf the net for instance. Try a little belly breathing: Belly breathing is cool; very relaxing. Sit down - on the floor is best. Some women sit with their legs crossed but you can sit any way you like. Place both hands on your belly. Then breathe - slowly exhale and inhale while expanding your belly in and out. You should pull your belly in as you exhale and out on the inhale. This may seem too simple to be doing any good, but it helps to clear your mind and relax. Also, it builds strength in your abdominals and helps you to push affectively during childbirth. You can learn proper belly breathing in a prenatal yoga class.
Tags: birthing ball get ready for labor labor breathing labor exercises pelvic tilt squat
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A Frael of Figs
- or -
A Handful of History
If history consisted only in lists of the dates when "important people" did earth-shattering things such as kicking the bucket from a surfeit of lampreys, then I would agree with Henry Ford that history is bunk.
However, history at large can run from the present day all the way back to the big bang - assuming there ever was a big bang.
Working from a simple principle, geologists figured out the geological processes which have made the face of our planet what it is today. That simple principle states that the processes which we observe today must have operated the same way in the past and will certainly operate the same way in the future.
That is the essence of uniformitarianism, a principle of geology first formulated in a scientific manner by James Hutton.
Uniformitarianism admits a rule of uniformity of process operation throughout geological history. By extension, it can be formulated as a law of universal and cosmic application: the laws of physics are the same for all observers under the same conditions across time and space.
Some of the historical evidence accumulated by geologists came from archives. Processes operating today were seen to have operated in a similar way in the past according to eye-witness accounts. But the planet itself is the most wonderful illustrated history book that one could wish for. The language which is found in its ages-old pages is universal.
And so it was that history gave value to geology and geology gave value to physics.
Without history, science is bunk.
I have no time for bunk, so I like to check up on what is presented as historical fact by checking up on the available evidence.
Scientific evidence can be found in the strangest places. The strangest of all places, perhaps, is the archive of tax laws and payments where one can find evidence of geological and climatic processes in historic times. Bad times make bad markets.
I leave it as an exercise for the reader to determine whether my delving into tax archives is to be taken as evidence of the past, or as evidence of my need to get a life.
Historic weights and measures
My recent articles on Ignaz Venetz show that he adopted the metric system some time after 1821. His 1821 paper uses Swiss leagues and feet, while his posthumous paper uses those units together with meters. The French word lieue (league) is often translated as mile, but that is imprecise. A league is not necessarily the same measure in all lands.
I often wonder how scientists managed to communicate measurements with precision in an even more remote past. If you think it's bad enough converting between British, U.S. and metric units, try going back to the times when not just every region, but every trade had its own preferred units of measure.
Here is a small sample of oddball archaic units compiled from old tax and toll-related documents and various web sources.
- 70,000 cochineal insects
- of cocoa 1 cwt
- of bullion, 15 to 30 lb
- of anchovies 30 lb
- beef 25 stone
- butter 224 lb
- candles 120 lb
- coffee 3 to 11 cwt
- flour 196 lb
- gunpowder 1 cwt
- herrings 32 gall
- Malaga figs 96 to 360 lb
- pork 28 stone
- potashes 120 lb
- resin 2 cwt
- soap 256 lb
- tar 261 imp. gals
- tapioca 1.1/4 cwt
- turpentine 2 to 2.1/2 cwt
- Valencia raisins 1 cwt
chaldron ( a kind of coal wagon)
- of coal 25.1/2 cwt
- Newcastle chaldron of coal 52 1/2 cwt or 3 wains (a kind of farm wagon)
cubic yard
- of new hay 6 stone (84 lb)
- of old hay 8 stone (1 cwt)
faggot - of steel 120 lb
firkin - of soap 64 lb
frael or frail (various other spellings: a basket made from rushes)
- of Faro figs 32 lb
- of Malaga figs 56 lb
jordan (a box)
- of almonds 25 lb
- of bricks 100 pieces
long hundred
- of fish 132
- of hops 1.1/2 to 2 cwt
- of glass 120 lb
- of almonds 1.1/4cwt
- of cochineal 140 lb
- of lead 2,400 lb
- of fish 4 pieces
And there are many hundreds of local and trade-special units which would take a whole book to list. It would, of course, be the most 'remaindered' book in the history of publishing. Boring wouldn't even begin to describe it!
If you have enjoyed this article, you may enjoy other articles from my blog. |
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Albarello drug jar for 'the Blessed Laxative', Italy, 1601-1700
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Glossary: humours
The fluids of the body whose balance is essential to well-being. They are blood, choler (yellow bile), phlegm, and melancholy (black bile). The system of the humours was closely related to the theory of the elements by the Ancient Greeks (especially Hippocrates), who were the first society to widely embrace the theory and apply it to medical practice. In Ancient Roman culture, the theory of the humours was embraced by Galen. During the neo-classical revival in western culture, the theory of the humours was a dominant form of medical practice. Its legacy in the form of activities such as blood-letting continued in England into the eighteenth century.
Glossary: pharmacy
The preparation and medicinal dispensing of drugs.
Glossary: albarello
Glossary: phlegm
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6.1 Lines and Angles
6.2 Triangles
6.3 Polygons
6.4 Circles
6.5 Key Formulas
6.6 Review Questions
6.7 Explanations
1. C
Because lines l and m are parallel and line AB is a transversal, the angle whose measure is labeled as 120º is supplementary to .
Now we have a 30-60-90 triangle whose longer leg, AC, is also the distance between lines l and m. Using the :: side ratios for 30-60-90 triangles you can use the hypotenuse length to calculate the lengths of the other two legs. The short leg has a : ratio to the hypotenuse, so its length is 5/2. The long leg has a : ration to the short leg, so its length is 52.
2. E
Let’s analyze each statement separately.
1. This statement implies that DF = EF. We know that BF = AF because it is given that line CF is the perpendicular bisector of AB, and by definition, F is the midpoint of AB. It is also given that the area of triangle CDB is equal to the area of triangle CEA. These two triangles share the same height, and since the area of a triangle is found by the formula 12 b h, it follows that if their areas are equal, their bases are equal too. If BD = AE, then by subtracting DE from each segment, we have BE = AD and thus EF = DF. So statement I is true.
2. This statement is simply not backed by any evidence. All we know is that BE = AD, EF = DF, and BF = AF. As long as points E and D are equidistant from F, all these conditions hold, so there is no guarantee that they are the midpoints of BF and AF, respectively. E and D could be anywhere along BF and AF, respectively, as long as they are equidistant from F. Thus, this statement is not necessarily true.
3. Triangles CDB and CEA are equal in area; this is given. By subtracting the area of triangle CED from each of these triangles, we see that triangles CEB and CDA must have the same area. This statement is true.
Only statements I and III must be true.
3. C
The area of a triangle with base x and height h is given by the formula 12xh. The area of a square with sides of length x is x2. Since you know the two shapes have equal areas, you can set the two expressions equal to each other and solve for h:
The correct answer is h = 2x.
4. D
If ABD is an equilateral triangle, then AD = AB = BD = 4, and all the sides of the rhombus have a length of 4 (by definition of a rhombus, all sides are congruent). Also, by definition of a rhombus, opposite angles are congruent, so . Draw an altitude from a to DC to create a 30-60-90 triangle, and from the length ratio of x : x : 2x among the sides, you can calculate the length of this altitude to be 2. The area of a rhombus is bh, so the area of this rhombus is 4 2 = 8.
5. D
The length of the arc depends on the circumference of the circle and the measure of the central angle that intercepts that arc. The formula is:
where n is the measure of the central angle that intercepts the arc and r is the radius.
Angle c is the inscribed angle or one-half as large as the central angle that intercepts the circle at the same points. So the measure of this angle is 2cº.
Now simply plug the values into the formula: the length of arc AB is:
2π(8) = =
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Horticultural Hate The Mystery of the Forest Swastikas
A Swastika as a Birthday Gift?
It didn't take long for rumors to spread about how the swastika got there in the first place. A local farmer claimed that he had planted the trees as a child, with a forester paying him a few cents for each seedling he put in the ground. Others reported that it was put there as a sign of loyalty after a nearby villager had been taken to the Sachsenhausen concentration camp by the Nazis because he had secretly been listening to the BBC. Still another version holds that a local Nazi leader ordered the trees planted on the occasion of Hitler's birthday. Finally, the Berliner Zeitung newspaper reported that it was planted in gratitude to the Reich Labor Service for building a street in Zernikow.
A Scramble to Remove Trees
But the forestry workers were badly mistaken. It took five years before their error was discovered, but in 2000, the news agency Reuters published photos of a bright yellow and clearly visible swastika in the forest near Zernikow -- even if the edges were a bit frayed. And the media response was once again immense. Even the Chicago Tribune wrote about it, noting that the swastika forest was not helpful for a region that had already become notorious for racist violence.
Fads and Fables
In Sept. 2006, the New York Times also reported on a complete forest near the remote village of Tash-Bashat, in Kyrgystan, shaped as a swastika. The origins of this swastika in reverse measuring some 180 meters (600 feet) across were also shrouded in legend and uncertainty. One villager claimed that an ethnic German forest supervisor, who had been exiled to the east but was a Nazi sympathizer, directed the planting of the forest in the 1940s. Another reported that the trees had been planted by a mysterious "professor" in the 1960s before he was taken away by the KGB. A local guide said the trees had been planted in the late 1930s as a sign of German-Russian friendship when Hitler and Stalin signed the Molotov-Ribbentrop non-aggression pact. Reporter C.J. Chivers also found legends the forest had been planted by German POWs pressed into forestry duty. He never did track down its true origins, but he wrote that, if it really really was planted by German prisoners, the "symmetry in the tree line … may be the Third Reich's only practical joke."
Discuss this issue with other readers!
5 total posts
Show all comments
Page 1
wmasterson1 07/06/2013
1. optional
Really?...Let it go. The Nazi's aren't the enemy anymore. They have been gone for sixty eight years now.
chasidot 07/07/2013
2. Not
Not "Horticultural"! "Arboreal"! Can't Germans speak English? ;) Warmest regards from a loyal reader,
Pierre 07/08/2013
3. optional
This is like the crop circles, later proven to be man-made. Some neo-Nazis or pranksters simply using chemicals to manipulate foliage color. A simple analysis of a wood sample, leaf sample and a sample of soil would solve the "mystery"...
Robb 07/08/2013
4. Resurgence of Nazism
"wmasterson1": Sir, my respects. However, perhaps atomic bombs in Iran will demonstrate that the Nazis are restless sleepers. The last time I looked, Nazis were antisemitic, although you can correct me. That "Jewish Problem" just won't stay asleep. It crops up everywhere people are inveigled into ignorance and blame others when they themselves are cesspools. The Jewish question is the bellwether, once its going and active, you know destruction is coming along presently.
spon-facebook-1667454646 07/09/2013
5. why not add?
You know, it woudn't be too difficult to neutralize that pattern by adding to it. Just plant a few more larches to fill-in the 'box.' It'll take a few years to fill in, but grow-back won't be a problem. ____ |_|_| |_|_|
Show all comments
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Science / Physics knowledge
Random Science or Physics Quiz
Can you name the answers about physics concepts?
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For a given object on a given surface is the coefficient of static friction or kinetic friction greater?
Centripetal acceleration goes in what direction relative to it's circular path of motion?
If they have the same velocity, which object has more momentum: a car or a feather?
Is every single particle in the universe gravitationally attracted to every other particle in the universe?
What physicist united the five 'versions' of string theory and introduced M theory?
Do photons have mass?
True or False: Scientists will someday be able to construct telescopes powerful enough to see a black hole?
What can a quantity be labeled if it essentially measures volume, and has both direction and magnitude?
What does Newton's first law of motion define? (one word answer)
The Heisenberg uncertainty principle states that you cannot know what two things about an electron?
What will a force acting on an object (not in equilibrium) cause it to do?
What units is force commonly measured in?
Which is faster, an object moving at 1 kilometer per hour, or 1 mile per hour
Does a planet with a radius twice that of earth but the same mass have greater or lesser gravitational attraction?
The term 'valence' is mostly associated with what particle?
About how long would it take to travel from one edge of our galaxy to the other at the speed of light?
In the equation E=mc squared, what constant does 'c' stand for?
About what is the speed of light in meters per second? (in a vacuum)
The average distance from the earth to sun is defined as what unit of measurement? (a meter/lightyear/inch)
What greek letter is used to symbolize wavelength?
Energy is commonly measured in what units?
In the study of momentum there are two types of collisions. What are they?
What type of force causes an object to twist or rotate?
The number of stars in the milky way is estimated at what power of 10? (hundreds, thousands, millions...)
Angular acceleration is described using what greek letter?
What is the metric equivalent to the english degrees? (not temperature)
How many radians complete a circle in terms of pi?
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Each Degree of Global Warming Linked to 20,000 Deaths a Year
STANFORD, California, January 3, 2007 (ENS) – For each increase of one degree Celsius in the global temperature caused by carbon dioxide emissions, the resulting air pollution would lead annually to about 1,000 additional deaths and many more cases of respiratory illness and asthma across the United States, finds new Stanford University research released today.
Worldwide, upward of 20,000 air pollution related deaths per year per degree Celsius may be due to heat-trapping carbon dioxide emissions, according to the paper by Mark Jacobson, a professor of civil and environmental engineering at Stanford.
The research is the first to track the health effects of carbon dioxide emissions. It documents the direct links between increased levels of carbon dioxide in the atmosphere and increases in human mortality.
For Californians the effect is even greater. Jacobson’s paper offers concrete evidence that California is facing a particularly difficult situation if carbon dioxide emissions increase.
Air pollution in Los Angeles,
California (Photo courtesy U.S. EPA)
The study finds that the effects of carbon dioxide’s warming are greatest where pollution is already severe. Given that California has six of the 10 U.S. cities with the worst air quality, the state is likely to bear an increasingly disproportionate burden of death if no new restrictions are placed on carbon dioxide emissions.
The new findings, to be published in the journal “Geophysical Research Letters,” come to light just after the U.S. Environmental Protection Agency’s ruling against states setting their own emission standards for this greenhouse gas based in part on the lack of data showing the link between carbon dioxide emissions and their health effects.
On December 19, 2007, the EPA denied California and 16 other states a waiver that would have allowed the states to set their own emission standards for carbon dioxide, which is not currently regulated. The EPA denied the waiver partly on the grounds that no special circumstances existed to warrant an exception for the states.
Stephen Johnson, the EPA administrator, said California’s petition for a waiver of federal standards was denied because the state had failed to prove the “extraordinary and compelling conditions” required to qualify for a waiver.
“With six of the 10 most polluted cities in the nation being in California, that alone creates a special circumstance for the state,” Jacobson said.
Increased warming due to carbon dioxide will worsen people’s health in those cities at a much faster clip than elsewhere in the nation, he said.
Jacobson said more than 30 percent of the 1,000 excess deaths due to each degree Celsius increase caused by carbon dioxide occurred in California, which has a population of about 12 percent of the United States.
“This is a cause and effect relationship, not just a correlation,” said Jacobson. “The study is the first specifically to isolate carbon dioxide’s effect from that of other global-warming agents and to find quantitatively that chemical and meteorological changes due to carbon dioxide itself increase mortality due to increased ozone, particles and carcinogens in the air.”
He observed that higher temperatures due to carbon dioxide increased the chemical rate of ozone production in urban areas. And he noticed that increased water vapor due to carbon dioxide-induced higher temperatures boosted chemical ozone production even more in urban areas.
“Ultimately, you inhale a greater abundance of deleterious chemicals due to carbon dioxide and the climate change associated with it, and the link appears quite solid,” he said. “The logical next step is to reduce carbon dioxide: That would reduce its warming effect and improve the health of people in the U.S. and around the world who are currently suffering from air pollution health problems associated with it.”
Jacobson added that much of the population of the United States already has been directly affected by climate change through the air they have inhaled over the last few decades and that the health effects would grow worse if temperatures continue to rise.
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Facts About The Taj Mahal
One can see two identical buildings on either side of the Taj. These monuments are entirely made of red sandstone. While both these buildings are mosques, the one towards the west (left side of the Taj) is important and used for offering prayers, as it not only sanctifies the Taj but also faces Mecca. The replica on the other side is known as the Jawab (answer).
Taj Mahal serves as a backdrop for the annual Taj Mahotsav (Taj festival), which is usually held in the month of February. The Taj Mahotsav is a celebration of traditional Indian art forms and crafts. The main events of this festival include classical dance performances by leading dance exponents and musical recitals by maestros, apart from display of various craft products and cultural shows.
The canals and waterworks within the Charbagh provide a grand reflection of the Taj, further emphasizing the imagery of the paradise. The Muslims regard the Koran as a mirror image of a tablet in heaven, while the 'Tree of Life' grows upside down in the garden within the paradise. The architects who built the Taj Mahal made the canals and the waterworks in the garden, with the purpose of generating an upside down image of the Taj, to gel with the divine inspiration.
After the completion of Taj Mahal each garden within the Charbagh was divided into 16 flowerbeds, making a total of 64. It is said that each flowerbed was planted with 400 plants. Trees were planted carefully in accordance with the symmetry of the overall plan. The trees, which were generally preferred, were either cypress (Cuprussus) (signifying death) or different fruit bearing trees (signifying life). These trees housed some of the most exotic birds, all of which added to the breathtaking environs of the Taj. The water channels crisscrossing the garden used to be full of colorful fish of various species. Special care was taken to maintain the garden, its waterworks as members of the royal family frequented it and stayed in the guesthouse (mehmankhana) near it. THE MAUSOLEUM The central path within the garden leads you to the Taj Mahal, which is placed on a high plinth (platform). The plinth is 6.7 m (21.98 ft) high and covers an area of 95 sq m (1,022.57 square feet). A double staircase facing the entrance to the tomb is the only way, which takes you on top of it. This plinth or pedestal is an ideal place from where you can have a panoramic view of the surroundings, which includes the lush green Charbagh in the front and the riverfront at the backside. From here, you can also admire the white towering structure of the Taj.
There are four elegant tapering minarets, one on each corner of the plinth. Each of the minarets is 41.6 m (136.48 ft) high and is capped by a small cupola. The minarets, not only balance the main structure of the mausoleum, but are also placed in such a way that in case of a mishap, they do not fall over the main edifice. Each pillar has a letter written on it, which put together spell the word ar-rahman (all merciful) - one of the many names of Allah. The main structure of the Taj Mahal is square and is beveled at its corners. Each side of the Taj Mahal is 56.6 m (185.69 ft) long. On each facade arched recesses arranged in two stories flank a high iwan in the center. The top border of the iwan on each side rises higher than the rest of façade, thus concealing the neck of the dome behind it. A central bulbous dome crowns the magnificent structure. This dome is further surrounded by four chhatris (domed canopy, supported by pillars/cupola). Each of which is topped by a small finial. The dome is an important component of the Islamic style of architecture, as it is believed to be a link between heaven and earth. While the square structure of the edifice represents the material world, the dome symbolizes the vault of heaven. The octagonal part symbolizes the transitional phase between heaven and earth. The dome is topped by a brass finial, whose tip rises to a height of 73 m above the ground. Above the finial is the realm of transcendence. The entire structure of the dome is designed as a replica of God's throne in paradise, where a gigantic pearl dome stands supported by four corner pillars. According to Islam the rivers of grace flow through this dome. The outer walls of the Taj Mahal are decorated in a number of places with shallow marble carving apart from the elegant pietra dura work, which can be seen near arched recesses and borders. The entrance to the tomb leads you to the central hall, which houses the false tombs and has four small octagonal halls, grouped around it. The original graves are located in a crypt, which is directly below the central hall. The four smaller rooms were originally created for housing the graves of other members of the royal family. The tomb of Mumtaz Mahal, in whose honor the Taj Mahal was built, lies directly below the dome. The tomb is placed in such a manner that it is in direct alignment with the main entrance. The tomb of Shahjahan is much larger and is placed next to that of his beloved queen. The tombs are decorated with exquisite pietra dura (stone inlay) work. Apart from unexcelled inlay work the tomb of Mumtaz Mahal is inscribed by 99 different names of Allah. It is said that the royal graves once laid inside a gem encrusted gold railing, which was later removed and replaced by an octagonal, all marble lattice (jali-perforated screen) screen of the most exquisite craftsmanship. Delicate inlay work can be seen on the surface of the screen. The floral decorations on the screen are amazing. Some flowers created on the screen are made up of as many as 64 pieces. The different sections of the screen are carved out of a single piece of marble. Various sections of the screen are joined together with gilded fasteners and the entrance is fashioned out of jasper, in the Turkish style. |
New home for elephants on rampage
NAROK, Kenya: Wildlife rangers have begun relocating 50 rampaging elephants back to the renowned Maasai Mara game reserve to stem rising human deaths and property destruction in outlying villages.
On Thursday, the first four of the elephants, due to be relocated over the next 10 days, were shot with tranquilliser darts from a helicopter near Narok, about 150 kilometres south of the capital, Nairobi, a notorious zone for human-wildlife conflict.
Once the giant animals lost consciousness, conservationists carefully winched them up by crane onto trucks for the journey to the Maasai Mara, from where they had been cut off by widening settlement, increasing farming and deforestation.
"The greatest challenge to Kenyan wildlife conservation today is Kenya's population growth," said the Kenya Wildlife Service director, Julius Kipng'etich.
Workers splashed the elephants with water to cool them before giving another injection to wake them up, ready for their 150-kilometre truck journey to the Maasai Mara.
If the operation is a success for the first 50 animals, wildlife service plans to move 200 of them.
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How much would it cost for the average local to buy a luxury apartment in the world's most important cities? In Singapore, it would take four decades of income. In Shanghai, two centuries. And in Mumbai -- poor souls -- they'd be looking at a good three centuries of hard work.
Those numbers come courtesy of Bloomberg, which yesterday compiled the chart below (I've recomposed it for readability). The news service calculated how many years worth of earnings it would take the average national to buy a high-end, roughly 100-square-meter piece of real estate in each city. (That comes out to about 328-square-feet, or a studio apartment in America).
Now what does this chart tell us, other than the fact that Manhattan home buyers have nothing to complain about compared to, say, Parisians? Each market has its own unique circumstances. But I think this graph is largely about the impact of globalization on property, that most local of all commodities.
The top three cities on this list have all developed wildly wealthy upper classes thanks to global trade, whether they're oil oligarchs in Russia or chemicals magnate in India. But they also have widespread poverty and a relatively tiny middle class. Cities in the developed world are also paying a different kind of globalization premium. In London, for instance, fancy apartments have become hot investments for the rich international buyers looking for a place to park their money. The same thing is happening in Sydney, where wealthy Asians are also snapping up residences as investments, or sometimes as places to retire.
Of course, there are probably exceptions. Manhattan has enough of its own uber-wealthy to push the cost of prime real estate to astronomical heights without help from abroad. But as the world's rich get richer, we can expect the most expensive cities to become more expensive. At least, that is, if you're in the market for a place as cool as this. |
Setting realistic goals for robotic welding projects
November 15, 2001
By: Jim Berge
Expecting a robot to solve all of your production problems can inflict the cruel irony of ceating more. If you want your robots to speed up your operation, know what they can and can't do from the start.
Companies interested in purchasing robotic weldingequipment often expect robots to solve all their productivity and quality problems. After installation, the actual results often do not meet the end user's high expectations. The natural conclusion is that the robot company dropped the ball; but very often, the problem is unrealistic expectations that are created either by the robot seller or the end users themselves.
Therefore, an important step is to abide by a realistic set of expectations for those who are specifying, purchasing, and installing robotic welding equipment. These guidelines not only can prevent disappointments resulting from false expectations, but also can help make your robotic welding project more profitable and dependable.
Define the Project
The exact requirements of your robotic welding system need to be defined clearly before the system is designed. Will parts be pretacked, or will loose parts be clamped into fixtures? Is the primary goal increased quality, operator safety, increased productivity, or some combination of these? Are you just playing with the idea of robotic welding, or are you serious about it and convinced that this technology is something you need? Do you need robots because you can't find qualified welders to hire?
Be clear about the reasons you're interested in robotic welding. This will help guide the project along a predictable path.
When it comes time to specify and purchase a system, be involved in its design and functionality. This does not mean that you, the end user, are responsible for the actual design, but you must become intimately familiar with the system before it's built and stay on top of design changes as they happen. This will prevent surprises and disappointments in the future-for instance, in case the system becomes too big to fit into the floor space you have provided for it or cannot reach certain weld spots.
What Robots Can Do, Can't Do
Do not expect your robot to compensate for quality problems such as poor component tolerances or fit-up.
In the early days of robotic welding (the late '70s and early '80s), a lot of robotic welding projects failed. Robot companies didn't understand all the requirements of making a project successful, and end users thought robots were the magic cure-all for their production woes.
To prevent such exercises in futility, do a lot of homework before you purchase your first robotic welding system. Production controls and quality systems should be put in place before you consider automated welding.
Many companies already may have put these systems in place, perhaps simply to improve the quality of their manually welded products. In such cases, the foundation for a successful robot installation already has been laid. However, most manufacturing facilities that still are welding their products manually and doing things the same way they did 20 years ago need to put some basic quality controls in place to ensure the repeatability of component parts.
Robots have a hard time dealing with gaps between component parts, and they don't like welding on parts that are not repeatable. Although part-to-part variations in the weld joint can be detected-seam finding and tracking are common robot options-these things consume cycle time and also have their limitations.
The best solution is to strive toward producing consistent piece parts with little or no gaps between parts. Smart part design and fixture design are crucial elements here. Do the homework, and don't expect the robot to compensate for poor preparation. If necessary, buy good press brakes or laser cutting machinery or new tooling for existing presses and punches to optimize component part quality.
Taking Some Welding Away From Robots
At times it may make more sense to have the robot do less welding. Most end users are highly disappointed to learn that the expensive robot they bought can reach only 90 percent of the welds on a particular assembly. Or they approach a project assuming that the more welding the robot does, the more justified the cost of the project is. These assumptions may not necessarily be true. Consider the following:
1. Improve quality by taking welds away from the robot. Some welds just are not suited for robots. For instance, the complicated contours created when welds wrap around corners sometimes are difficult for robots to do.
For cases in which gaps simply cannot be avoided at any cost, it may be necessary for an operator to weld a stringer bead in the gap before presenting the parts to the robot. These are a couple instances in which quality actually can improve by giving certain welds to operators.
2. Improve throughput by taking welds away from the robot. If the fixture load/unload time is significantly less than the robot cycle time, operators may be idle for long periods of time. Sometimes you can give other tasks to operators to take advantage of this slack time, but in many cases, it may make sense to give some of the robot welds to the operator to do.
By giving 10 percent of the more difficult welds to the operator, the robot cycle time will be shortened, and what may have been unproductive time for the operator becomes productive. The overall effect is better utilization of the operator's time, improved throughput due to decreased cycle times, and possibly higher quality because you chose the most difficult robot welds to hand off to the operator.
3. Improve justification by taking welds away from the robot. Since throughput is improved with what could essentially be the same amount of labor, the return on investment is improved. Also, increased quality can reduce the amount of rework, thus reducing overall cost.
Plan for and Implement Proper Training
Planning for proper training up-front and actually making it happen can be opposite sides of the same coin.
It's easy to envision which training courses are necessary, to plan for a gradual startup, and to purchase various levels of training. But when it comes time to implement all of this, it can seem far too time-consuming and unproductive. Production, after all, is the biggest priority, and proper training often is neglected.
Don't give in to this mentality. The type and extent of training provided can make or break an automated welding project. Certain things just cannot be rushed. For example, an important part of training is learning to troubleshoot, whether you're talking about robotic programs, welding data, or hardware problems (electrical or mechanical). The problem with troubleshooting, though, is that it usually is needed for uncommon or intermittent problems. Therefore, gaining the proper knowledge and experience can take time, maybe even weeks or months.
In general, the type of training most commonly discussed deals with learning the robot's language, how to operate the machinery and recover from errors, and how to adjust the characteristics of the machine to operate in different circumstances. Robot suppliers have developed effective training courses, and it is essential at least to take the basic language course. But any time an advanced course is offered, whether it focuses on advanced language functions or optional equipment and devices such as seam tracking, participation should be considered mandatory.
There is a direct correlation between an operator or programmer's depth of training and an ability to troubleshoot problems quickly and keep the robot producing.
Service Support and Preventive Maintenance
First, a preventive maintenance (PM) plan that actually is implemented (not just given lip service) is crucial to the dependable performance of a robotic welding cell.
Few people would neglect to change the oil in their cars, but many robot purchasers think it is unnecessary to perform any PM on their equipment. Good prevention certainly pays for itself in increased uptime and productivity. In many cases, good PM programs also can improve quality by, for instance, requiring new or serviced contact tips, liners, nozzles, and wire feed rollers on a regular basis. All of these items contribute to a stable welding arc, which translates into better quality and process reliability.
Maintenance training also is critical, because warranty periods are limited. It makes sense to train your own maintenance and service personnel thoroughly, to get repairs done more quickly, and get back into production as soon as possible. Many robot companies provide separate classes for mechanical service (lubricating, replacing motors and gearboxes) and electrical service (troubleshooting circuit boards, tracking down failed components). Both are necessary, though each class may involve different people in your facility.
Having taken the preparations to properly train personnel in the operation, programming, preventive maintenance, and troubleshooting of the equipment, you will be faced with fewer surprises and will be able to keep the equipment in production-which is why robots are purchased in the first place.
Realistic expectations begin at the concept stage of a robot project. If the system is conceptualized and designed properly, there is a better chance it will work as expected.
The next step is to take pains with homework and prepare the upstream processes (and, in some cases, the downstream processes) to be compatible with robotic welding. A realistic expectation about how much of the welding the robot will do on a particular assembly can prevent unpleasant surprises about the robot's productivity.
Proper training in programming, operation, maintenance, and troubleshooting can and will contribute to a robotic welding system that works as expected.
Berge Robotics
Jim Berge
Contributing Writer
Berge Robotics
Sherveport, LA
Phone: 970-222-1753 |
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As Sovereign as You Act
Edward L. Cline, Sr came from a long line of leaders. Both grandfathers and his father served on the Umonhon Tribal Council, and so did Mr. Cline himself at various times in his life. His granddaughter, Kyla Cline-Snake, remembers times when her grandfather would speak passionately about the days of old and how everyone would call each other by their given Native American names. Edward L. Cline, Sr. was Waca’be Zhinga, or Little Black Bear. He was often heard saying “you’re as sovereign as you act” and there is a lot of meaning in those 6 words. Sovereignty has been said to deliver a connection, which bares responsibly, to work in the best interest of the people. As with many great leaders, it is this responsibility that drives individuals to accomplish great things.
As a young man, Waca’be Zhinga, was a keen observer. Growing up during the depression, very few jobs existed and tribal people faced tremendous struggles on many fronts. Lack of appropriate education, good health care, homes, and solutions to address social issues, left many in Indian country looking for answers. Witnessing these struggles first hand, Waca’be Zhinga with our tribal leaders and many of the leaders across native lands, worked as advocates for change to address these and many other challenges for all people. Waca’be Zhinga was part of the Coalition of Indian Controlled School Boards that reformed education for the Umonhon people, and resulted in our Macy Public School System. He drove efforts that led to the Carl T. Curtis Health Care facility and developed housing programs and social programs. Additionally, much of our governance structure along with the Justice center has been grown through the efforts of Waca’be Zhinga and the Umonhon tribal leaders. While researching documents, Waca’be Zhinga discovered that thousands of acres of land were taken from the Umonhon people. A shift in course of the Ni shu da, the smoky waters of the Missouri had happened, and land reemerged to the Iowa side to be claimed by white farmers. Waca’be Zhinga stood strong with persistence and tenacity along with our other tribal leaders to win a battle that took decades against the federal government and white farmers to reclaim the Blackbird Bend land for the Umonhon people. As a tribal leader and chairman for the Umonhon Nation, Waca’be Zhinga, carried the virtue of humility, not wishing to take credit for the many things he worked to accomplish, however we owe much to our current and past leadership for the efforts and actions they take. I believe the legacy of Waca’be Zhinga leaves behind wisdom for all about this responsibility to work in the best interest of the people and I am proud that our new Macy Facility, Waca’be Zhinga Higher Education Center (Little Black Bear), carries his name. |
What Is Involved in Stress Relieving Steel?
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Stress relieving steel is a heat treatment process that involves subjecting a steel workpiece or part to a specific temperature for a particular amount of time. The temperature at which stress relieving takes place is determined by the transformation temperature, which can be a different figure for various steel alloys. Each steel workpiece can also require a different amount of time, as the entire part must be allowed to reach the stress relieving temperature. After the desired temperature has been reached, the workpiece can be removed and allowed to cool down. This process typically takes place after machining, and it is meant to remove internal stresses from the steel.
Steel is an iron alloy that can contain varying amounts of carbon, though other metals such as manganese and tungsten can also be used. This metal alloy is very strong and resilient, but machining it can introduce undesired stresses into the physical structure of a part. Stress relieving steel is one way to deal with this situation, and machined steel parts may warp or crack during use if this type of action is not taken. This process can relieve over 90% the internal stress within steel, and is particularly useful for large cast or welded parts, in addition to workpieces from which a lot of material was removed during machining.
The general process for stress relieving steel is the same for all different alloys, though the specifics of the procedure can differ. This process involves introducing heat to steel parts after the machining process, the exact temperature of which depends on the alloy in question. In general, the stress relieving temperature is around 75° C (170° F) less than the transformation temperature steel. Since steel typically has a transformation temperature of about 730° C (1340° F), the correct temperature for stress relieving steel is roughly 655° C (1170° F). Alloys that make use of other metals, or significantly different carbon levels, typically have higher transformation temperatures, so stress relieving those types of steel often requires more heat.
After a machined steel workpiece has been subjected to the stress relieving temperature, it has to be left there until the part has heated up all the way through. At that point, the part can be removed from the heat, and the final step of stress relieving steel is to allow the workpiece to cool down. There is no quenching involved in this part of the process, and the parts are typically left to air cool without the benefit of fans or any other external cooling methods.
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Stress relieving steel for steel used in industrial projects is a large scale process, but there are ways you can heat and strengthen steel at home.
Yes, you can actually use some of the soft steel items you have around your home to create stronger steel products such as chisels, knives and swords. I don't know that you will have much use for a sword, but it is an option.
You can find out the specifics online, but the general heating process can be completed in a barbecue grill. You will also need a heating torch, coals and tongs. The whole setup reminds me of the pictures I have seen of blacksmiths at work.
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While stress relieving steel is most closely associated with improving the strength of steel, the heating process can help in other areas as well. Stress relieving can make the steel more easy to handle and manipulate with the machinery used to produce steel products.
In general, stress relieving steel makes it easier to shape and makes it stronger. This also translates into steel products that are more user friendly.
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What is the Marginal Productivity Theory?
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Marginal productivity theory is an economic concept that postulates a firm should only add variable costs so long as they bring value to the company. For example, labor is a variable cost necessary for producing goods. Hiring too many workers when materials or equipment to produce goods are limited will increase costs while not adding value to the company. Marginal productivity theory is also a concept measuring economies of scale. This determines how much value a company will generate through increasing production output.
Economic theory relies heavily on the estimation or marginal benefits versus marginal costs. In economic terms, companies will set the price for goods and services where marginal revenue equals marginal cost. This will maximize sales to consumers. In order to achieve this profit maximization point, companies will need to calculate the variable costs that will increase when they look to increase production. These costs include materials and labor, primarily.
When marginal costs increase too much, the marginal productivity theory states that companies are better off not producing goods. This theory bases its concepts on the fact that companies that continue to produce goods at costs higher than revenue will be unable to achieve a economies of scale. Costs will continue to eat away at the company’s profits and will eventually reduce the company’s capital balances, potentially leading the company into bankruptcy. This is also known as the law of diminishing returns in marginal productivity theory. At some point, a company is unable to produce more goods to increase its economic value.
Economies of scale occur when a company can increase its production output to a point where it lowers fixed costs allocated to goods. Both fixed costs and the marginal cost increases are offset through increased production and the ability of the company to saturate the market with more products. The returns from the economies of scales may be reduced, however, if a competitor also attempts to increase output.
Marginal productivity theory can also face other factors that will reduce its impact on a company. For example, consumer income, threat of substitute goods, and limit barriers of entry can reduce the company’s market power and profit maximization. If consumers' income decreases, they are unable to purchase goods or services. Substitute goods are products a consumer will see as a cheaper product that will offer the same value as the original good. Limited or no barriers to entry means that consumer demand can result in other companies easily entering the market and producing similar goods that will earn profits.
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Adjective: bedded be-did
1. (geology) deposited or arranged in horizontal layers
"bedded rock";
- stratified
2. Having a bed or beds as specified
Verb: bed (bedded,bedding) bed
1. Furnish with a bed
"The inn keeper could bed all the new arrivals"
2. Place (plants) in a prepared bed of soil
3. Put to bed
"The children were bedded at ten o'clock"
4. Have sexual intercourse
5. Prepare for sleep
"He goes to bed at the crack of dawn";
See also: double-bedded, foliaceous, foliate, foliated, laminal, laminar, layered, sheetlike, single-bedded, superimposed, twin-bedded
Type of: copulate, couple, furnish, lay, mate, pair, place, plant, pose, position, provide, put, render, set, supply
Antonym: bedless
Encyclopedia: Bed, Bath and Be Gone |
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Noun: ulnar nerve
1. A nerve running along the inner side of the arm and passing near the elbow; supplies intrinsic muscles of the hand and the skin of the medial side of the hand
- cubital nerve, nervus ulnaris
Derived forms: ulnar nerves
Type of: nerve, nervus
Part of: arm
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Art Essay on William Kentridge
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The political content and the unique techniques of William Kentridge's work have propelled him into being one of South Africa's top artists. Working with what is in essence a very restrictive media, using only charcoal and a touch of blue or red pastel, he has created animations of astounding depth. A theme running through all of his work is his peculiar way of representing South Africa. He does not portray it as the very militant or oppressive place that it was for black people but he doesn't emphasize the picturesque state of living that white people enjoyed during Apartheid either. Instead he presents a city in which the duality of man is exposed. In his series of nine short films he introduces two characters, namely Soho Eckstein and Felix Teitlebaum. These characters depict an emotional and political struggle that ultimately reflects the life of many South Africans of the time.
Not only in Felix In Exile but in all his animated works the concept of time and change is a major theme that. The way he does this is through his erasure technique which contrasts with conventional cell animation whose seamlessness de-emphasizes the fact that it is actually a succession of hand-drawn images, This is implemented by drawing a key frame, erasing certain areas of it, then re-drawing them and thus... |
Essay by PaperNerd ContributorHigh School, 12th grade July 2001
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Did Life Come From Mars? The origin of life was the subject of the lecture. For example, there are mountains in western Australia that have the oldest fossils that had ever been discovered on this earth. The oldest fossil that was found was 3.6 billion years old. It is called the Marroona group. But life billions of years ago was ruff. About 4 million years ago asteroids bombarded the earth. Every 10-100 million years dinosaur killing asteroids hit the earth. An asteroid that is very known is called Eros. This very large asteroid is seven and a half kilometers across. It has impact scars from other objects hitting it that dates back from 3.5-4.8 million years ago. Luckily this asteroid is not heading towards the earth. Also the atmosphere of the earth is 3000 degrees so most asteroids burn up before reaching the land that we stand on.
About 3.5
billion years ago there is evidence of life photosynthesizing. It's known that bacteria were living in hot springs in Yellowstone National Park. Life can exist without light. When I was young I was taught that life is based around light. That is wrong and proof of that is in the Sea Bay. A ship drilled seven kilometers down into solid rock in the Sea Bay and live organisms were found. There are three types of organisms. One of then is called the Eucarya and it is a complex organism. Then there is bacteria and it is minimal comparing to the Eucarya. Last is the Archaea. But what is amazing is that the Eucarya has a nucleus.
Mars can have life because life doesn't necessarily have to be in the surface of the planet. It could be underneath the surface. In the late 1970's NASA sent out the Viking landing... |
Tort Reform
Essay by bigdaddyoneUniversity, Master'sA+, January 2009
download word file, 9 pages 3.0
Tort Reform iRunning head: TORT REFORMThe Purpose and Efficiency of Tort ReformTort Reform iiAbstractIn any reforms encouraged by a government, it has proven to create a great impact on the lives of people. In an increasingly litigious society, tort reform is a subject that had brought about great debate. With costs never ceasing their inevitable rise, especially in the medical field, tort reform discussion has increased. The cause and effect of lawsuits, and the cure of huge settlements, live in a world of gray, and not black and white. Truly, something needs to be done, but the implementation of legislative controls is a very touchy subject, with powerful lobbies on both sides.
Tort Reform 1Is Tort Reform A Cure?Tort Reform had been a popular political issue, especially in the United States. With its aim to improve the efficiency of courts and limit the compensation and tort litigation among victims, its concept had become an issue in past presidential elections.
According to an article written by Shrager, Spivey and Sachs, the method of tort reform has the tendency to limit the rights of victims and may even promote injustice to the oppressed wherein tort reform is believed to have emphasized in protecting the people causing harm or damage upon the victim. (Shrager, Spivey and Sachs, 2007)The word tort came from the French legal term avoir tort, which means 'to have wronged.' The cases under tort involve inflicting harm to a person's reputation, security, financial sources or property. For instance, two of the main examples of tort cases are personal injury and medical malpractice, when a patient sues a surgeon; the surgeon would not be imprisoned. Instead, the surgeon is obliged to pay for the expenses and medical bills in order to recompense the suffering and damages caused to the patient. |
A Child's History of England
by Charles Dickens
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Chapter XVI - England Under Edward the First, Called Longshanks
It was now the year of our Lord one thousand two hundred and seventy-two; and Prince Edward, the heir to the throne, being away in the Holy Land, knew nothing of his father's death. The Barons, however, proclaimed him King, immediately after the Royal funeral; and the people very willingly consented, since most men knew too well by this time what the horrors of a contest for the crown were. So King Edward the First, called, in a not very complimentary manner, Longshanks, because of the slenderness of his legs, was peacefully accepted by the English Nation.
His legs had need to be strong, however long and thin they were; for they had to support him through many difficulties on the fiery sands of Asia, where his small force of soldiers fainted, died, deserted, and seemed to melt away. But his prowess made light of it, and he said, 'I will go on, if I go on with no other follower than my groom!'
A Prince of this spirit gave the Turks a deal of trouble. He stormed Nazareth, at which place, of all places on earth, I am sorry to relate, he made a frightful slaughter of innocent people; and then he went to Acre, where he got a truce of ten years from the Sultan. He had very nearly lost his life in Acre, through the treachery of a Saracen Noble, called the Emir of Jaffa, who, making the pretence that he had some idea of turning Christian and wanted to know all about that religion, sent a trusty messenger to Edward very often - with a dagger in his sleeve. At last, one Friday in Whitsun week, when it was very hot, and all the sandy prospect lay beneath the blazing sun, burnt up like a great overdone biscuit, and Edward was lying on a couch, dressed for coolness in only a loose robe, the messenger, with his chocolate-coloured face and his bright dark eyes and white teeth, came creeping in with a letter, and kneeled down like a tame tiger. But, the moment Edward stretched out his hand to take the letter, the tiger made a spring at his heart. He was quick, but Edward was quick too. He seized the traitor by his chocolate throat, threw him to the ground, and slew him with the very dagger he had drawn. The weapon had struck Edward in the arm, and although the wound itself was slight, it threatened to be mortal, for the blade of the dagger had been smeared with poison. Thanks, however, to a better surgeon than was often to be found in those times, and to some wholesome herbs, and above all, to his faithful wife, Eleanor, who devotedly nursed him, and is said by some to have sucked the poison from the wound with her own red lips (which I am very willing to believe), Edward soon recovered and was sound again.
As the King his father had sent entreaties to him to return home, he now began the journey. He had got as far as Italy, when he met messengers who brought him intelligence of the King's death. Hearing that all was quiet at home, he made no haste to return to his own dominions, but paid a visit to the Pope, and went in state through various Italian Towns, where he was welcomed with acclamations as a mighty champion of the Cross from the Holy Land, and where he received presents of purple mantles and prancing horses, and went along in great triumph. The shouting people little knew that he was the last English monarch who would ever embark in a crusade, or that within twenty years every conquest which the Christians had made in the Holy Land at the cost of so much blood, would be won back by the Turks. But all this came to pass.
There was, and there is, an old town standing in a plain in France, called Châlons. When the King was coming towards this place on his way to England, a wily French Lord, called the Count of Châlons, sent him a polite challenge to come with his knights and hold a fair tournament with the Count and his knights, and make a day of it with sword and lance. It was represented to the King that the Count of Châlons was not to be trusted, and that, instead of a holiday fight for mere show and in good humour, he secretly meant a real battle, in which the English should be defeated by superior force.
The King, however, nothing afraid, went to the appointed place on the appointed day with a thousand followers. When the Count came with two thousand and attacked the English in earnest, the English rushed at them with such valour that the Count's men and the Count's horses soon began to be tumbled down all over the field. The Count himself seized the King round the neck, but the King tumbled him out of his saddle in return for the compliment, and, jumping from his own horse, and standing over him, beat away at his iron armour like a blacksmith hammering on his anvil. Even when the Count owned himself defeated and offered his sword, the King would not do him the honour to take it, but made him yield it up to a common soldier. There had been such fury shown in this fight, that it was afterwards called the little Battle of Châlons.
The English were very well disposed to be proud of their King after these adventures; so, when he landed at Dover in the year one thousand two hundred and seventy-four (being then thirty-six years old), and went on to Westminster where he and his good Queen were crowned with great magnificence, splendid rejoicings took place. For the coronation-feast there were provided, among other eatables, four hundred oxen, four hundred sheep, four hundred and fifty pigs, eighteen wild boars, three hundred flitches of bacon, and twenty thousand fowls. The fountains and conduits in the street flowed with red and white wine instead of water; the rich citizens hung silks and cloths of the brightest colours out of their windows to increase the beauty of the show, and threw out gold and silver by whole handfuls to make scrambles for the crowd. In short, there was such eating and drinking, such music and capering, such a ringing of bells and tossing of caps, such a shouting, and singing, and revelling, as the narrow overhanging streets of old London City had not witnessed for many a long day. All the people were merry except the poor Jews, who, trembling within their houses, and scarcely daring to peep out, began to foresee that they would have to find the money for this joviality sooner or later.
To dismiss this sad subject of the Jews for the present, I am sorry to add that in this reign they were most unmercifully pillaged. They were hanged in great numbers, on accusations of having clipped the King's coin - which all kinds of people had done. They were heavily taxed; they were disgracefully badged; they were, on one day, thirteen years after the coronation, taken up with their wives and children and thrown into beastly prisons, until they purchased their release by paying to the King twelve thousand pounds. Finally, every kind of property belonging to them was seized by the King, except so little as would defray the charge of their taking themselves away into foreign countries. Many years elapsed before the hope of gain induced any of their race to return to England, where they had been treated so heartlessly and had suffered so much.
If King Edward the First had been as bad a king to Christians as he was to Jews, he would have been bad indeed. But he was, in general, a wise and great monarch, under whom the country much improved. He had no love for the Great Charter - few Kings had, through many, many years - but he had high qualities. The first bold object which he conceived when he came home, was, to unite under one Sovereign England, Scotland, and Wales; the two last of which countries had each a little king of its own, about whom the people were always quarrelling and fighting, and making a prodigious disturbance - a great deal more than he was worth. In the course of King Edward's reign he was engaged, besides, in a war with France. To make these quarrels clearer, we will separate their histories and take them thus. Wales, first. France, second. Scotland, third.
Llewellyn was the Prince of Wales. He had been on the side of the Barons in the reign of the stupid old King, but had afterwards sworn allegiance to him. When King Edward came to the throne, Llewellyn was required to swear allegiance to him also; which he refused to do. The King, being crowned and in his own dominions, three times more required Llewellyn to come and do homage; and three times more Llewellyn said he would rather not. He was going to be married to Eleanor de Montfort, a young lady of the family mentioned in the last reign; and it chanced that this young lady, coming from France with her youngest brother, Emeric, was taken by an English ship, and was ordered by the English King to be detained. Upon this, the quarrel came to a head. The King went, with his fleet, to the coast of Wales, where, so encompassing Llewellyn, that he could only take refuge in the bleak mountain region of Snowdon in which no provisions could reach him, he was soon starved into an apology, and into a treaty of peace, and into paying the expenses of the war. The King, however, forgave him some of the hardest conditions of the treaty, and consented to his marriage. And he now thought he had reduced Wales to obedience.
But the Welsh, although they were naturally a gentle, quiet, pleasant people, who liked to receive strangers in their cottages among the mountains, and to set before them with free hospitality whatever they had to eat and drink, and to play to them on their harps, and sing their native ballads to them, were a people of great spirit when their blood was up. Englishmen, after this affair, began to be insolent in Wales, and to assume the air of masters; and the Welsh pride could not bear it. Moreover, they believed in that unlucky old Merlin, some of whose unlucky old prophecies somebody always seemed doomed to remember when there was a chance of its doing harm; and just at this time some blind old gentleman with a harp and a long white beard, who was an excellent person, but had become of an unknown age and tedious, burst out with a declaration that Merlin had predicted that when English money had become round, a Prince of Wales would be crowned in London. Now, King Edward had recently forbidden the English penny to be cut into halves and quarters for halfpence and farthings, and had actually introduced a round coin; therefore, the Welsh people said this was the time Merlin meant, and rose accordingly.
King Edward had bought over Prince David, Llewellyn's brother, by heaping favours upon him; but he was the first to revolt, being perhaps troubled in his conscience. One stormy night, he surprised the Castle of Hawarden, in possession of which an English nobleman had been left; killed the whole garrison, and carried off the nobleman a prisoner to Snowdon. Upon this, the Welsh people rose like one man. King Edward, with his army, marching from Worcester to the Menai Strait, crossed it - near to where the wonderful tubular iron bridge now, in days so different, makes a passage for railway trains - by a bridge of boats that enabled forty men to march abreast. He subdued the Island of Anglesea, and sent his men forward to observe the enemy. The sudden appearance of the Welsh created a panic among them, and they fell back to the bridge. The tide had in the meantime risen and separated the boats; the Welsh pursuing them, they were driven into the sea, and there they sunk, in their heavy iron armour, by thousands. After this victory Llewellyn, helped by the severe winter-weather of Wales, gained another battle; but the King ordering a portion of his English army to advance through South Wales, and catch him between two foes, and Llewellyn bravely turning to meet this new enemy, he was surprised and killed - very meanly, for he was unarmed and defenceless. His head was struck off and sent to London, where it was fixed upon the Tower, encircled with a wreath, some say of ivy, some say of willow, some say of silver, to make it look like a ghastly coin in ridicule of the prediction.
David, however, still held out for six months, though eagerly sought after by the King, and hunted by his own countrymen. One of them finally betrayed him with his wife and children. He was sentenced to be hanged, drawn, and quartered; and from that time this became the established punishment of Traitors in England - a punishment wholly without excuse, as being revolting, vile, and cruel, after its object is dead; and which has no sense in it, as its only real degradation (and that nothing can blot out) is to the country that permits on any consideration such abominable barbarity.
Wales was now subdued. The Queen giving birth to a young prince in the Castle of Carnarvon, the King showed him to the Welsh people as their countryman, and called him Prince of Wales; a title that has ever since been borne by the heir-apparent to the English throne - which that little Prince soon became, by the death of his elder brother. The King did better things for the Welsh than that, by improving their laws and encouraging their trade. Disturbances still took place, chiefly occasioned by the avarice and pride of the English Lords, on whom Welsh lands and castles had been bestowed; but they were subdued, and the country never rose again. There is a legend that to prevent the people from being incited to rebellion by the songs of their bards and harpers, Edward had them all put to death. Some of them may have fallen among other men who held out against the King; but this general slaughter is, I think, a fancy of the harpers themselves, who, I dare say, made a song about it many years afterwards, and sang it by the Welsh firesides until it came to be believed.
The foreign war of the reign of Edward the First arose in this way. The crews of two vessels, one a Norman ship, and the other an English ship, happened to go to the same place in their boats to fill their casks with fresh water. Being rough angry fellows, they began to quarrel, and then to fight - the English with their fists; the Normans with their knives - and, in the fight, a Norman was killed. The Norman crew, instead of revenging themselves upon those English sailors with whom they had quarrelled (who were too strong for them, I suspect), took to their ship again in a great rage, attacked the first English ship they met, laid hold of an unoffending merchant who happened to be on board, and brutally hanged him in the rigging of their own vessel with a dog at his feet. This so enraged the English sailors that there was no restraining them; and whenever, and wherever, English sailors met Norman sailors, they fell upon each other tooth and nail. The Irish and Dutch sailors took part with the English; the French and Genoese sailors helped the Normans; and thus the greater part of the mariners sailing over the sea became, in their way, as violent and raging as the sea itself when it is disturbed.
King Edward's fame had been so high abroad that he had been chosen to decide a difference between France and another foreign power, and had lived upon the Continent three years. At first, neither he nor the French King Philip (the good Louis had been dead some time) interfered in these quarrels; but when a fleet of eighty English ships engaged and utterly defeated a Norman fleet of two hundred, in a pitched battle fought round a ship at anchor, in which no quarter was given, the matter became too serious to be passed over. King Edward, as Duke of Guienne, was summoned to present himself before the King of France, at Paris, and answer for the damage done by his sailor subjects. At first, he sent the Bishop of London as his representative, and then his brother Edmund, who was married to the French Queen's mother. I am afraid Edmund was an easy man, and allowed himself to be talked over by his charming relations, the French court ladies; at all events, he was induced to give up his brother's dukedom for forty days - as a mere form, the French King said, to satisfy his honour - and he was so very much astonished, when the time was out, to find that the French King had no idea of giving it up again, that I should not wonder if it hastened his death: which soon took place.
King Edward was a King to win his foreign dukedom back again, if it could be won by energy and valour. He raised a large army, renounced his allegiance as Duke of Guienne, and crossed the sea to carry war into France. Before any important battle was fought, however, a truce was agreed upon for two years; and in the course of that time, the Pope effected a reconciliation. King Edward, who was now a widower, having lost his affectionate and good wife, Eleanor, married the French King's sister, Margaret; and the Prince of Wales was contracted to the French King's daughter Isabella.
Out of bad things, good things sometimes arise. Out of this hanging of the innocent merchant, and the bloodshed and strife it caused, there came to be established one of the greatest powers that the English people now possess. The preparations for the war being very expensive, and King Edward greatly wanting money, and being very arbitrary in his ways of raising it, some of the Barons began firmly to oppose him. Two of them, in particular, Humphrey Bohun, Earl of Hereford, and Roger Bigod, Earl of Norfolk, were so stout against him, that they maintained he had no right to command them to head his forces in Guienne, and flatly refused to go there. 'By Heaven, Sir Earl,' said the King to the Earl of Hereford, in a great passion, 'you shall either go or be hanged!' 'By Heaven, Sir King,' replied the Earl, 'I will neither go nor yet will I be hanged!' and both he and the other Earl sturdily left the court, attended by many Lords. The King tried every means of raising money. He taxed the clergy, in spite of all the Pope said to the contrary; and when they refused to pay, reduced them to submission, by saying Very well, then they had no claim upon the government for protection, and any man might plunder them who would - which a good many men were very ready to do, and very readily did, and which the clergy found too losing a game to be played at long. He seized all the wool and leather in the hands of the merchants, promising to pay for it some fine day; and he set a tax upon the exportation of wool, which was so unpopular among the traders that it was called 'The evil toll.' But all would not do. The Barons, led by those two great Earls, declared any taxes imposed without the consent of Parliament, unlawful; and the Parliament refused to impose taxes, until the King should confirm afresh the two Great Charters, and should solemnly declare in writing, that there was no power in the country to raise money from the people, evermore, but the power of Parliament representing all ranks of the people. The King was very unwilling to diminish his own power by allowing this great privilege in the Parliament; but there was no help for it, and he at last complied. We shall come to another King by-and-by, who might have saved his head from rolling off, if he had profited by this example.
The people gained other benefits in Parliament from the good sense and wisdom of this King. Many of the laws were much improved; provision was made for the greater safety of travellers, and the apprehension of thieves and murderers; the priests were prevented from holding too much land, and so becoming too powerful; and Justices of the Peace were first appointed (though not at first under that name) in various parts of the country.
And now we come to Scotland, which was the great and lasting trouble of the reign of King Edward the First.
About thirteen years after King Edward's coronation, Alexander the Third, the King of Scotland, died of a fall from his horse. He had been married to Margaret, King Edward's sister. All their children being dead, the Scottish crown became the right of a young Princess only eight years old, the daughter of Eric, King of Norway, who had married a daughter of the deceased sovereign. King Edward proposed, that the Maiden of Norway, as this Princess was called, should be engaged to be married to his eldest son; but, unfortunately, as she was coming over to England she fell sick, and landing on one of the Orkney Islands, died there. A great commotion immediately began in Scotland, where as many as thirteen noisy claimants to the vacant throne started up and made a general confusion.
King Edward being much renowned for his sagacity and justice, it seems to have been agreed to refer the dispute to him. He accepted the trust, and went, with an army, to the Border-land where England and Scotland joined. There, he called upon the Scottish gentlemen to meet him at the Castle of Norham, on the English side of the river Tweed; and to that Castle they came. But, before he would take any step in the business, he required those Scottish gentlemen, one and all, to do homage to him as their superior Lord; and when they hesitated, he said, 'By holy Edward, whose crown I wear, I will have my rights, or I will die in maintaining them!' The Scottish gentlemen, who had not expected this, were disconcerted, and asked for three weeks to think about it.
At the end of the three weeks, another meeting took place, on a green plain on the Scottish side of the river. Of all the competitors for the Scottish throne, there were only two who had any real claim, in right of their near kindred to the Royal Family. These were John Baliol and Robert Bruce: and the right was, I have no doubt, on the side of John Baliol. At this particular meeting John Baliol was not present, but Robert Bruce was; and on Robert Bruce being formally asked whether he acknowledged the King of England for his superior lord, he answered, plainly and distinctly, Yes, he did. Next day, John Baliol appeared, and said the same. This point settled, some arrangements were made for inquiring into their titles.
The inquiry occupied a pretty long time - more than a year. While it was going on, King Edward took the opportunity of making a journey through Scotland, and calling upon the Scottish people of all degrees to acknowledge themselves his vassals, or be imprisoned until they did. In the meanwhile, Commissioners were appointed to conduct the inquiry, a Parliament was held at Berwick about it, the two claimants were heard at full length, and there was a vast amount of talking. At last, in the great hall of the Castle of Berwick, the King gave judgment in favour of John Baliol: who, consenting to receive his crown by the King of England's favour and permission, was crowned at Scone, in an old stone chair which had been used for ages in the abbey there, at the coronations of Scottish Kings. Then, King Edward caused the great seal of Scotland, used since the late King's death, to be broken in four pieces, and placed in the English Treasury; and considered that he now had Scotland (according to the common saying) under his thumb.
Scotland had a strong will of its own yet, however. King Edward, determined that the Scottish King should not forget he was his vassal, summoned him repeatedly to come and defend himself and his judges before the English Parliament when appeals from the decisions of Scottish courts of justice were being heard. At length, John Baliol, who had no great heart of his own, had so much heart put into him by the brave spirit of the Scottish people, who took this as a national insult, that he refused to come any more. Thereupon, the King further required him to help him in his war abroad (which was then in progress), and to give up, as security for his good behaviour in future, the three strong Scottish Castles of Jedburgh, Roxburgh, and Berwick. Nothing of this being done; on the contrary, the Scottish people concealing their King among their mountains in the Highlands and showing a determination to resist; Edward marched to Berwick with an army of thirty thousand foot, and four thousand horse; took the Castle, and slew its whole garrison, and the inhabitants of the town as well - men, women, and children. Lord Warrenne, Earl of Surrey, then went on to the Castle of Dunbar, before which a battle was fought, and the whole Scottish army defeated with great slaughter. The victory being complete, the Earl of Surrey was left as guardian of Scotland; the principal offices in that kingdom were given to Englishmen; the more powerful Scottish Nobles were obliged to come and live in England; the Scottish crown and sceptre were brought away; and even the old stone chair was carried off and placed in Westminster Abbey, where you may see it now. Baliol had the Tower of London lent him for a residence, with permission to range about within a circle of twenty miles. Three years afterwards he was allowed to go to Normandy, where he had estates, and where he passed the remaining six years of his life: far more happily, I dare say, than he had lived for a long while in angry Scotland.
Now, there was, in the West of Scotland, a gentleman of small fortune, named William Wallace, the second son of a Scottish knight. He was a man of great size and great strength; he was very brave and daring; when he spoke to a body of his countrymen, he could rouse them in a wonderful manner by the power of his burning words; he loved Scotland dearly, and he hated England with his utmost might. The domineering conduct of the English who now held the places of trust in Scotland made them as intolerable to the proud Scottish people as they had been, under similar circumstances, to the Welsh; and no man in all Scotland regarded them with so much smothered rage as William Wallace. One day, an Englishman in office, little knowing what he was, affronted him. Wallace instantly struck him dead, and taking refuge among the rocks and hills, and there joining with his countryman, Sir William Douglas, who was also in arms against King Edward, became the most resolute and undaunted champion of a people struggling for their independence that ever lived upon the earth.
The English Guardian of the Kingdom fled before him, and, thus encouraged, the Scottish people revolted everywhere, and fell upon the English without mercy. The Earl of Surrey, by the King's commands, raised all the power of the Border-counties, and two English armies poured into Scotland. Only one Chief, in the face of those armies, stood by Wallace, who, with a force of forty thousand men, awaited the invaders at a place on the river Forth, within two miles of Stirling. Across the river there was only one poor wooden bridge, called the bridge of Kildean - so narrow, that but two men could cross it abreast. With his eyes upon this bridge, Wallace posted the greater part of his men among some rising grounds, and waited calmly. When the English army came up on the opposite bank of the river, messengers were sent forward to offer terms. Wallace sent them back with a defiance, in the name of the freedom of Scotland. Some of the officers of the Earl of Surrey in command of the English, with their eyes also on the bridge, advised him to be discreet and not hasty. He, however, urged to immediate battle by some other officers, and particularly by Cressingham, King Edward's treasurer, and a rash man, gave the word of command to advance. One thousand English crossed the bridge, two abreast; the Scottish troops were as motionless as stone images. Two thousand English crossed; three thousand, four thousand, five. Not a feather, all this time, had been seen to stir among the Scottish bonnets. Now, they all fluttered. 'Forward, one party, to the foot of the Bridge!' cried Wallace, 'and let no more English cross! The rest, down with me on the five thousand who have come over, and cut them all to pieces!' It was done, in the sight of the whole remainder of the English army, who could give no help. Cressingham himself was killed, and the Scotch made whips for their horses of his skin.
King Edward was abroad at this time, and during the successes on the Scottish side which followed, and which enabled bold Wallace to win the whole country back again, and even to ravage the English borders. But, after a few winter months, the King returned, and took the field with more than his usual energy. One night, when a kick from his horse as they both lay on the ground together broke two of his ribs, and a cry arose that he was killed, he leaped into his saddle, regardless of the pain he suffered, and rode through the camp. Day then appearing, he gave the word (still, of course, in that bruised and aching state) Forward! and led his army on to near Falkirk, where the Scottish forces were seen drawn up on some stony ground, behind a morass. Here, he defeated Wallace, and killed fifteen thousand of his men. With the shattered remainder, Wallace drew back to Stirling; but, being pursued, set fire to the town that it might give no help to the English, and escaped. The inhabitants of Perth afterwards set fire to their houses for the same reason, and the King, unable to find provisions, was forced to withdraw his army.
Another Robert Bruce, the grandson of him who had disputed the Scottish crown with Baliol, was now in arms against the King (that elder Bruce being dead), and also John Comyn, Baliol's nephew. These two young men might agree in opposing Edward, but could agree in nothing else, as they were rivals for the throne of Scotland. Probably it was because they knew this, and knew what troubles must arise even if they could hope to get the better of the great English King, that the principal Scottish people applied to the Pope for his interference. The Pope, on the principle of losing nothing for want of trying to get it, very coolly claimed that Scotland belonged to him; but this was a little too much, and the Parliament in a friendly manner told him so.
In the spring time of the year one thousand three hundred and three, the King sent Sir John Segrave, whom he made Governor of Scotland, with twenty thousand men, to reduce the rebels. Sir John was not as careful as he should have been, but encamped at Rosslyn, near Edinburgh, with his army divided into three parts. The Scottish forces saw their advantage; fell on each part separately; defeated each; and killed all the prisoners. Then, came the King himself once more, as soon as a great army could be raised; he passed through the whole north of Scotland, laying waste whatsoever came in his way; and he took up his winter quarters at Dunfermline. The Scottish cause now looked so hopeless, that Comyn and the other nobles made submission and received their pardons. Wallace alone stood out. He was invited to surrender, though on no distinct pledge that his life should be spared; but he still defied the ireful King, and lived among the steep crags of the Highland glens, where the eagles made their nests, and where the mountain torrents roared, and the white snow was deep, and the bitter winds blew round his unsheltered head, as he lay through many a pitch-dark night wrapped up in his plaid. Nothing could break his spirit; nothing could lower his courage; nothing could induce him to forget or to forgive his country's wrongs. Even when the Castle of Stirling, which had long held out, was besieged by the King with every kind of military engine then in use; even when the lead upon cathedral roofs was taken down to help to make them; even when the King, though an old man, commanded in the siege as if he were a youth, being so resolved to conquer; even when the brave garrison (then found with amazement to be not two hundred people, including several ladies) were starved and beaten out and were made to submit on their knees, and with every form of disgrace that could aggravate their sufferings; even then, when there was not a ray of hope in Scotland, William Wallace was as proud and firm as if he had beheld the powerful and relentless Edward lying dead at his feet.
Who betrayed William Wallace in the end, is not quite certain. That he was betrayed - probably by an attendant - is too true. He was taken to the Castle of Dumbarton, under Sir John Menteith, and thence to London, where the great fame of his bravery and resolution attracted immense concourses of people to behold him. He was tried in Westminster Hall, with a crown of laurel on his head - it is supposed because he was reported to have said that he ought to wear, or that he would wear, a crown there and was found guilty as a robber, a murderer, and a traitor. What they called a robber (he said to those who tried him) he was, because he had taken spoil from the King's men. What they called a murderer, he was, because he had slain an insolent Englishman. What they called a traitor, he was not, for he had never sworn allegiance to the King, and had ever scorned to do it. He was dragged at the tails of horses to West Smithfield, and there hanged on a high gallows, torn open before he was dead, beheaded, and quartered. His head was set upon a pole on London Bridge, his right arm was sent to Newcastle, his left arm to Berwick, his legs to Perth and Aberdeen. But, if King Edward had had his body cut into inches, and had sent every separate inch into a separate town, he could not have dispersed it half so far and wide as his fame. Wallace will be remembered in songs and stories, while there are songs and stories in the English tongue, and Scotland will hold him dear while her lakes and mountains last.
Released from this dreaded enemy, the King made a fairer plan of Government for Scotland, divided the offices of honour among Scottish gentlemen and English gentlemen, forgave past offences, and thought, in his old age, that his work was done.
But he deceived himself. Comyn and Bruce conspired, and made an appointment to meet at Dumfries, in the church of the Minorites. There is a story that Comyn was false to Bruce, and had informed against him to the King; that Bruce was warned of his danger and the necessity of flight, by receiving, one night as he sat at supper, from his friend the Earl of Gloucester, twelve pennies and a pair of spurs; that as he was riding angrily to keep his appointment (through a snow-storm, with his horse's shoes reversed that he might not be tracked), he met an evil-looking serving man, a messenger of Comyn, whom he killed, and concealed in whose dress he found letters that proved Comyn's treachery. However this may be, they were likely enough to quarrel in any case, being hot- headed rivals; and, whatever they quarrelled about, they certainly did quarrel in the church where they met, and Bruce drew his dagger and stabbed Comyn, who fell upon the pavement. When Bruce came out, pale and disturbed, the friends who were waiting for him asked what was the matter? 'I think I have killed Comyn,' said he. 'You only think so?' returned one of them; 'I will make sure!' and going into the church, and finding him alive, stabbed him again and again. Knowing that the King would never forgive this new deed of violence, the party then declared Bruce King of Scotland: got him crowned at Scone - without the chair; and set up the rebellious standard once again.
When the King heard of it he kindled with fiercer anger than he had ever shown yet. He caused the Prince of Wales and two hundred and seventy of the young nobility to be knighted - the trees in the Temple Gardens were cut down to make room for their tents, and they watched their armour all night, according to the old usage: some in the Temple Church: some in Westminster Abbey - and at the public Feast which then took place, he swore, by Heaven, and by two swans covered with gold network which his minstrels placed upon the table, that he would avenge the death of Comyn, and would punish the false Bruce. And before all the company, he charged the Prince his son, in case that he should die before accomplishing his vow, not to bury him until it was fulfilled. Next morning the Prince and the rest of the young Knights rode away to the Border-country to join the English army; and the King, now weak and sick, followed in a horse-litter.
Bruce, after losing a battle and undergoing many dangers and much misery, fled to Ireland, where he lay concealed through the winter. That winter, Edward passed in hunting down and executing Bruce's relations and adherents, sparing neither youth nor age, and showing no touch of pity or sign of mercy. In the following spring, Bruce reappeared and gained some victories. In these frays, both sides were grievously cruel. For instance - Bruce's two brothers, being taken captives desperately wounded, were ordered by the King to instant execution. Bruce's friend Sir John Douglas, taking his own Castle of Douglas out of the hands of an English Lord, roasted the dead bodies of the slaughtered garrison in a great fire made of every movable within it; which dreadful cookery his men called the Douglas Larder. Bruce, still successful, however, drove the Earl of Pembroke and the Earl of Gloucester into the Castle of Ayr and laid siege to it.
The King, who had been laid up all the winter, but had directed the army from his sick-bed, now advanced to Carlisle, and there, causing the litter in which he had travelled to be placed in the Cathedral as an offering to Heaven, mounted his horse once more, and for the last time. He was now sixty-nine years old, and had reigned thirty-five years. He was so ill, that in four days he could go no more than six miles; still, even at that pace, he went on and resolutely kept his face towards the Border. At length, he lay down at the village of Burgh-upon-Sands; and there, telling those around him to impress upon the Prince that he was to remember his father's vow, and was never to rest until he had thoroughly subdued Scotland, he yielded up his last breath.
Anton Chekhov
Nathaniel Hawthorne
Susan Glaspell
Mark Twain
Edgar Allan Poe
Mary E. Wilkins Freeman
Herman Melville
Stephen Leacock
Kate Chopin
Bjørnstjerne Bjørnson |
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Leadership competencies
Leadership competencies. Please give me guidance on starting on this topic.
There is an argument that leaders today face an unprecedented array of macro environment challenges -- globalization, diversity, fast pacing, constant change, technological advances, nomadic workforce, talent shortage, systemic impatience and generational friction.
Given that, discuss the competencies that leaders must master and deploy to be effective in this environment. Discuss traditional competencies that are still appropriate and relevant, those traditional competencies that must evolve and new competencies that must emerge.
You decide the format and what to include.
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First, there are some traditional competencies that are still relevant and leaders should possess them. The leaders should have passion, should be well organized and should know how to delegate effectively. Passion is required for globalization, the ability to be well organized is essential for the challenges of technological advances, and the ability to delegate is important, especially when faced with a nomadic workforce. Even in the current environment, the leader must be able to communicate effectively, should have the ability to take responsibility, and be honest. Lack of ...
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The write up gives a learned discussion on Leadership competencies |
Chrome JavaScript
In this section we'll look into how to handle JavaScript data effectively, beginning with chrome code, in ways which will prevent pollution of shared namespaces and conflicts with other add-ons resulting from such global namespace pollution.
The first step to good JavaScript object management is having a namespace, or a JavaScript object that contains our code and data, that you know will not conflict with Firefox code or other extensions. Namespace declaration is best located in a file of its own, so that you have this one JS file that should be included in all of your XUL files.
We'll be using the placeholder 〈Namespace〉 below. This needs to be replaced with an identifier name which is unique to your add-on. If your add-on is called Sergeant Pepper, for instance, then SgtPepper would be a good namespace name.
* 〈Namespace〉 namespace.
if (typeof 〈Namespace〉 == "undefined") {
var 〈Namespace〉 = {};
Note: The naming standard that we normally follow is that the first part of the namespace corresponds to the development group (or company), and the second to the specific project. However, most extensions are small projects by individuals, so these examples follow a more practical approach of having just one namespace with the project name.
Notice how the 〈Namespace〉 namespace is declared using var. We need the namespace to be a global object that it can be used everywhere in the window chrome.
You can include functions in any namespace, since namespaces are just regular JS objects. That should come in handy when you have general utility functions or properties that you want to use across all objects within the namespace. For instance, there are frequently used XPCOM services such as the Observer service that can be included as members in the namespace:
* 〈Namespace〉 namespace.
var 〈Namespace〉 = {
* Initializes this object.
init : function() {
this.obsService =
JS objects can also be treated as string-indexed arrays:
// equivalent.
〈Namespace〉.Hello = {};
〈Namespace〉["Hello"] = {};
// equivalent.
This is very useful in cases where you have to set attributes or functions with dynamically generated names. It's one of the funky properties of JavaScript: all objects are nothing more than name / value mappings. You can add or replace functions and attributes to any Javascript object, at any moment you want. This is an odd, but powerful feature that comes in handy at times when things get complicated. For instance, you could replace a method in any object in the Firefox chrome, so that it behaves differently than how it normally does. This should be a last resort option, but it is very useful at times.
You usually need only one JS file to control a XUL window, since the code required is normally not that much. If you have complex behavior that requires too much code, look for ways to divide it into multiple objects and files. You can include as many scripts in a XUL window as you need.
To initialize your chrome objects, it's usually better to run the initialization code from the "load" event handler for the window. The load event is fired after the DOM on the window has loaded completely, but before it's displayed to the user. This allows you to manipulate and possibly change elements in the window without the user noticing the changes.
* Controls the browser overlay for the Hello World extension.
〈Namespace〉.BrowserOverlay = {
* Initializes this object.
init : function(aEvent) {
this._stringBundle = document.getElementById("xulschoolhello-string-bundle");
// you can make changes to the window DOM here.
// more stuff
"load", function() { 〈Namespace〉.BrowserOverlay.init(); }, false);
There are some things you can't (or shouldn't) do inside load handlers, such as closing the window being loaded, or opening new windows, alerts or dialogs. The window has to finish loading before it can do any of these things. They are bad UI practices anyway and you should avoid them. If you really need to do something like this anyway, one way to do it is to have a timeout execute the code after a delay:
init : function(aEvent) {
let that = this;
this._stringBundle = document.getElementById("xs-hw-string-bundle");
function() {
window.alert(that._stringBundle.getString("xulschoolhello.greeting.label")); }, 0);
The setTimeout function executes the function in the first parameter, after a delay in miliseconds specified by the second parameter. In this case we set the delay to 0, which means the function should be executed as soon as possible. Firefox has a minimum delay of 10-15ms (taken from this blog post), so it won't really run instantly. It is more than enough to let the window finish its load.
Use window.setTimeout and window.setInterval to control timed code execution. In case you're using JavaScript Code Modules or XPCOM objects, where a window object is not readily available, use an nsITimer instead.
This post suggests a way to achieve a true zero ms timeout, as a simple way to achieve parallelism in JS code.
Notice the way we send callback functions as parameters, and the use of an alternate reference for this which we always name that. This is all necessary due to a JavaScript feature (quirk would be a better word for it) called Method Binding. The consequence of doing this wrong is to have a this reference that doesn't do what you expected it to do. There are a few workarounds for this, and we use the ones we have found to be the most elegant and clear to read.
The general guideline we follow is this: whenever you have to set a callback function parameter, wrap it in an anonymous function. That is, something like function() { /* your code, usually a single function call. */ }. If you have to use a reference to this inside the function, declare a variable called that that equals this, and use that in the anonymous function.
JavaScript has a host of features that make it extremely flexible, but it also has some disadvantages, as it is not as strict as other languages, such as Java. A clear example of this is the fact that there are no private or public keywords that allow you to protect object members. As a alternative for this, a naming standard is frequently used to distinguish private and public members. There's no scope enforcement whatsoever, but this standard give others the chance to "play nice" and don't use private members.
Use "_" at the beginning of private attributes and methods in JS objects. For example: _stringBundle, _createUserNode().
Here's a short exercise to test a particular aspect of the chrome. Modify the Hello World extension so that the message says how many times it has been displayed. The message could say something like "Hello! This message has been shown 5 times." Keep the counter as a variable in the BrowserOverlay object, and increment it every time the message is going to be shown.
Once you have this working right, try the following: open the message a few times, so that the number increments. Now open a new window and display the message from the new window. What do you think will happen? What will the count be this time?
You probably didn't expect this, but the count was reset in the new window. Each window keeps its own counter, and now the extension is not behaving as expected. This is a fundamental lesson: the chrome is not global, it's window-specific. All of your scripts and objects are replicated for each window, and they work independently from each other. This is an issue that is very easy to overlook, since most Firefox users, specially power users, have a single window open at all times. You have to make sure you test your extension with multiple windows open; never assume everything will work the same as with a single window.
Now, in most cases you'll need to coordinate data in a way that it is consistent for all open Firefox windows. There are several ways in which you can do this. Preferences is one of them, and they are covered in another section of this tutorial. Two other ways are JavaScript Code Modules (Firefox 3 and above), and XPCOM.
JavaScript Code Modules
JavaScript Code Modules (also known as JSM) are new to Firefox 3, and they're the best tool for keeping everything in sync between windows. They're very simple to set up. The first thing you need to do is add an entry in the chrome.manifest file:
resource xulschoolhello modules/
Javascript code modules are accessed with the resource protocol, which is very similar to the chrome protocol. Just like with the chrome, we define the package name and then a path. To keep things simple, just locate the JSM files in a modules directory under the root of our project. In order to access a file messageCount.js in this directory, the URL would be:
Code modules are regular JS files, so there's nothing new in regards to naming or file types. Mozilla has adopted a standard of using the extension .jsm for these files, but they say .js is fine as well. To keep things simple, specially regarding code editors and default file associations in the developer's system, we have decided to stick with .js.
Download this version of the Hello World project with JSM to see the changes you need to make to the build system in order to include the files in the modules folder. They are minimal, and we add a very small Makefile.in file in the modules directory, just to keep everything separated and organized.
With the setup out of the way, let's get to it. What are JavaScript Code Modules?
A JavaScript Code Module is a regular JS file that specifies which of the declared elements in it are public. All module files should begin with a declaration like this:
var EXPORTED_SYMBOLS = ["〈ModuleNamespace〉"];
EXPORTED_SYMBOLS is a special identifier that tells Firefox that this file is only publishing the object named 〈ModuleNamespace〉. Several objects, functions and variables can be declared on this file, but the only object visible from the outside will be 〈ModuleNamespace〉, which is a namespace in our case. Because of namespacing, we don't need to worry much about what to export, usually we just need the namespace object. All of the objects inside of it are exported as well, since they are members of the 〈ModuleNamespace〉 object.
Module files can be imported to a chrome script or to other code modules with the following line:
When using Components.utils.import, code modules must be loaded using a file: or resource: URL pointing to a file on the disk. In particular, chrome: URLs (even those that point to a file outside a jar archive) are not valid.
To get a better idea, let's look at the code of the modified Hello World example. We have defined two files, one to declare namespaces and another one for the message count functionality mentioned in the previous exercise.
Here again we're using a placeholder, 〈ModuleNamespace〉, for the identifier name that you'll need to choose.
var EXPORTED_SYMBOLS = [ "〈ModuleNamespace〉" ];
const { classes: Cc, interfaces: Ci } = Components;
* 〈ModuleNamespace〉 namespace.
var 〈ModuleNamespace〉 = {};
This should all be familiar enough. We're declaring the namespace we'll use at the module level. We need a separate namespace for the chrome because the chrome namespace objects are repeated for each window, while the module namespace objects are unique for all windows. Setting window-specific data on code modules will lead to nothing but problems, so be careful when deciding what should be chrome and what shouldn't be. We needn't test for the pre-existence of our namespace object here, as modules are given their own namespace.
The 2 declared constants above are used to reduce code size. We frequently need to use XPCOM components in our code, so instead of doing this:
this.obsService =
It's better to do this:
this.obsService =
These 2 constants don't need to be defined in the overlay because they are already defined globally in the browser.js file in Firefox. We only need to define them when we're making windows of our own, or when we're working with code outside of the chrome (or porting your code to SeaMonkey, which doesn't have those constants declared in the main window).
Include the Cc and Ci constants in all XUL windows that are not overlays, all JSM files, and all XPCOM components (see further ahead). Do this even if you don't need them now. It's better to just make a habit out of it.
This is a point that is worth highlighting: modules work outside of the window scope. Unlike scripts in the chrome, modules don't have access to objects such as window, document, or other global functions, such as openUILink. These are all UI components and UI operations anyway, so they are better done in the chrome.
As a general guideline, we keep all of our business logic in JSM, available through service objects, and chrome scripts are limited to handle presentation logic.
We handle most of our code through static objects, singleton objects that don't require instantiation. But it is sometimes necessary to define classes and be able to create multiple instances. Common cases include interacting with a local database or a remote API. Data will often be translated into arrays of entities, and those are better represented through classes. One way to define a class is as follows:
* User class. Represents a Hello World user (whatever that may be).
〈ModuleNamespace〉.User = function(aName, aURL) {
this._name = aName;
this._url = aURL;
* User class methods.
〈ModuleNamespace〉.User.prototype = {
/* The name of the user. */
_name : null,
/* The URL of the user. */
_url : null,
* Gets the user name.
* @return the user name.
get name() {
return this._name;
* Gets the user URL.
* @return the user URL.
get url() {
return this._url;
In this example we defined a fictitious User class for the Hello World extension. Using the function keyword to define a class is odd, but this is just the JavaScript way: functions are also objects. The definition of the class acts as a constructor as well, and then you can define all other members using the prototype attribute. In this case we defined "getter" properties for the name and url members. This way we have immutable instances of our class. Well, only if consumers of the class play nice and don't change anything they shouldn't.
Creating an instance and using it is simple enough:
let user = new 〈ModuleNamespace〉.User("Pete", "http://example.com/pete");
This is something you can do with JS in general. You can use it in JSM, chrome, even on regular web pages. Since entities tend to be used all throughout an application, we think that having those classes defined at the module level is the best approach.
JSM is the best solution to handle objects that are window-independent. In the following section we'll discuss XPCOM, which is an older alternative to JSM and one of the foundations of Mozilla applications. You shouldn't skip that section because there are many common situations in extension development where you'll have to use XPCOM, maybe even implement XPCOM components of your own.
This tutorial was kindly donated to Mozilla by Appcoast.
Document Tags and Contributors
Last updated by: wbamberg, |
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Salts are frequently used for de-icing, but salt solutions are not used for cooling systems because they can cause severe corrosion to metals. Instead, non-corrosive antifreezes are commonly used for critical de-icing, such as for aircraft wings.
Automotive and internal combustion engine use[edit]
Fluorescent green-dyed antifreeze is visible in the radiator header tank when car radiator cap is removed
Most automotive engines are "water"-cooled to remove waste heat, although the "water" is actually antifreeze/water mixture and not plain water. The term engine coolant is widely used in the automotive industry, which covers its primary function of convective heat transfer for internal combustion engines. When used in an automotive context, corrosion inhibitors are added to help protect vehicles' radiators, which often contain a range of electrochemically incompatible metals (aluminum, cast iron, copper, brass, solder, et cetera). Water pump seal lubricant is also added.
Antifreeze was developed to overcome the shortcomings of water as a heat transfer fluid. In some engines freeze plugs (engine block expansion plugs) are placed in areas of the engine block where coolant flows in order to protect the engine from freeze damage[citation needed] if the ambient temperature drops below the freezing point of the antifreeze/water mixture. These should not be confused with core plugs, whose purpose is to allow removal of sand used in the casting process of engine blocks (core plugs will be pushed out if the coolant freezes, though, assuming that they adjoin the coolant passages, which is not always the case).
On the other hand, if the engine coolant gets too hot, it might boil while inside the engine, causing voids (pockets of steam), leading to localized hot spots and the catastrophic failure of the engine. If plain water were to be used as an engine coolant, it would promote galvanic corrosion. Proper engine coolant and a pressurized coolant system can help obviate the problems which make plain water incompatible with automotive engines. With proper antifreeze, a wide temperature range can be tolerated by the engine coolant, such as −34 °F (−37 °C) to +265 °F (129 °C) for 50% (by volume) propylene glycol diluted with water and a 15 psi pressurized coolant system.[1][2]
Early engine coolant antifreeze was methanol (methyl alcohol). Methanol was widely used in windshield fluids, however, in Europe, due to new REACH legislation, the use of methanol in windshield fluids is limited to 5% and in the near future will be further reduced to 3%.[3] As radiator caps were vented, not sealed, the methanol was lost to evaporation, requiring frequent replenishment to avoid freezing of the coolant. Methanol also accelerates corrosion of the metals, especially aluminum, used in the engine and cooling systems. Ethylene glycol was developed, and soon[when?] replaced methanol as an engine cooling system antifreeze. It has a very low volatility compared to methanol and to water. Before the 1950s, coolant systems were unpressurized and the engine was often cooler than modern automotive engines. By pressurizing the coolant system with a radiator cap, the boiling point of the fluid is increased, permitting higher engine temperatures and better fuel efficiency. Pressurized systems do not appreciably change the freezing point.
Other uses[edit]
The most common water-based antifreeze solutions used in electronics cooling are mixtures of water and either ethylene glycol (EGW) or propylene glycol (PGW). The use of ethylene glycol has a longer history, especially in the automotive industry. However, EGW solutions formulated for the automotive industry often have silicate based rust inhibitors that can coat and/or clog heat exchanger surfaces. Ethylene glycol is listed as a toxic chemical requiring care in handling and disposal.
Similar mixtures are commonly used in HVAC and industrial heating or cooling systems as a high-capacity heat transfer medium. Many formulations have corrosion inhibitors, and it is expected that these chemicals will be replenished (manually or under automatic control) to keep expensive piping and equipment from corroding.
Primary agents[edit]
Most antifreeze is made by mixing distilled water with some kind of alcohol.
Main article: Methanol
Methanol (also known as methyl alcohol, carbinol, wood alcohol, wood naphtha or wood spirits) is a chemical compound with chemical formula CH3OH. It is the simplest alcohol, and is a light, volatile, colorless, flammable, poisonous liquid with a distinctive odor that is somewhat milder and sweeter than ethanol (ethyl alcohol). At room temperature, it is a polar solvent and is used as an antifreeze, solvent, fuel, and as a denaturant for ethyl alcohol. It is not popular for machinery, but may be found in automotive windshield washer fluid, de-icers, and gasoline additives.
Ethylene glycol[edit]
Main article: Ethylene glycol
Ethylene glycol
Ethylene glycol solutions became available in 1926 and were marketed as "permanent antifreeze" since the higher boiling points provided advantages for summertime use as well as during cold weather. They are used today for a variety of applications, including automobiles, but gradually being replaced by propylene glycol due to its lower toxicity.
When ethylene glycol is used in a system, it may become oxidized to five organic acids (formic, oxalic, glycolic, glyoxalic and acetic acid). Inhibited ethylene glycol antifreeze mixes are available, with additives that buffer the pH and reserve alkalinity of the solution to prevent oxidation of ethylene glycol and formation of these acids. Nitrites, silicates, theodin, borates and azoles may also be used to prevent corrosive attack on metal.
Ethylene glycol is poisonous to humans and other animals,[4][5] and should be handled carefully and disposed of properly. Its sweet taste can lead to accidental ingestion or allow its deliberate use as a murder weapon.[6][7][8] Ethylene glycol is difficult to detect in the body, and causes symptoms—including intoxication, severe diarrhea, and vomiting—that can be confused with other illnesses or diseases.[4][8] Its metabolism produces calcium oxalate, which crystallizes in the brain, heart, lungs, and kidneys, damaging them; depending on the level of exposure, accumulation of the poison in the body can last weeks or months before causing death, but death by acute kidney failure can result within 72 hours if the individual does not receive appropriate medical treatment for the poisoning.[4] Some ethylene glycol antifreeze mixtures contain an embittering agent, such as denatonium, to discourage accidental or deliberate consumption.
Propylene glycol[edit]
Propylene glycol
Propylene glycol, on the other hand, is considerably less toxic than ethylene glycol and may be labeled as "non-toxic antifreeze". It is used as antifreeze where ethylene glycol would be inappropriate, such as in food-processing systems or in water pipes in homes where incidental ingestion may be possible. As confirmation of its relative non-toxicity, the FDA allows propylene glycol to be added to a large number of processed foods, including ice cream, frozen custard, salad dressings and baked goods, it is also often a main ingredient of E-cigarette liquid (E-liquid or E-juice).
Propylene glycol oxidizes when exposed to air and heat, forming lactic acid.[9][10] If not properly inhibited, this fluid can be very corrosive,[citation needed] so pH buffering agents such as dipotassium phosphate, Protodin and potassium bicarbonate are often added to propylene glycol, to prevent acidic corrosion of metal components. Pre-inhibited propylene glycol solutions like Dowfrost (manufactured by Dow Chemicals, US) and Tonofrost (manufactured by Chemtex Speciality Ltd, India) can also be used instead of pure propylene glycol to prevent corrosion.
Besides cooling system corrosion, biological fouling also occurs. Once bacterial slime starts to grow, the corrosion rate of the system increases. Maintenance of systems using glycol solution includes regular monitoring of freeze protection, pH, specific gravity, inhibitor level, color, and biological contamination. Propylene glycol should be replaced when it turns a reddish color.[11]
Once used for automotive antifreeze, glycerol has the advantage of being non-toxic, withstands relatively high temperatures, and is noncorrosive.
Glycerol was historically used as an antifreeze for automotive applications before being replaced by ethylene glycol, which has a lower freezing point. While the minimum freezing point of a glycerol-water mixture is higher than an ethylene glycol-water mixture, glycerol is not toxic and is being re-examined for use in automotive applications.[13][14] Glycerol is mandated for use as an antifreeze in many sprinkler systems.
In the laboratory, glycerol is a common component of solvents for enzymatic reagents stored at temperatures below 0 °C due to the depression of the freezing temperature of solutions with high concentrations of glycerol. It is also used as a cryoprotectant where the glycerol is dissolved in water to reduce damage by ice crystals to laboratory organisms that are stored in frozen solutions, such as bacteria, nematodes, and mammalian embryos.
Measuring the freeze point[edit]
Once antifreeze has been mixed with water and put into use, it periodically needs to be maintained. If engine coolant leaks, boils, or if the cooling system needs to be drained and refilled, the antifreeze's freeze protection will need to be considered. In other cases a vehicle may need to be operated in a colder environment, requiring more antifreeze and less water. Three methods are commonly employed to determine the freeze point of the solution:[15]
1. Specific gravity—(using a hydrometer or some sort of floating indicator),
2. Refractometer—which measures the refractive index of the antifreeze solution and translates it into freeze point, and
3. Test strips—specialized, disposable indicators made for this purpose.
Although ethylene glycol hydrometers are widely available and mass-marketed for antifreeze testing, they give false readings at high temperatures because specific gravity changes with temperature.[15] Propylene glycol solutions cannot be tested using specific gravity because of ambiguous results (40% and 100% solutions have the same specific gravity).[15]
Corrosion inhibitors[edit]
Most commercial antifreeze formulations include corrosion inhibiting compounds, and a colored dye (commonly a fluorescent green, red, orange, yellow, or blue) to aid in identification.[16] A 1:1 dilution with water is usually used, resulting in a freezing point of about −34 °F (−37 °C), depending on the formulation. In warmer or colder areas, weaker or stronger dilutions are used, respectively, but a range of 40%/60% to 60%/40% is frequently specified to ensure corrosion protection, and 70%/30% for maximum freeze prevention down to −84 °F (−64 °C).[2]
In the absence of leaks, antifreeze chemicals such as ethylene glycol or propylene glycol may retain their basic properties indefinitely. By contrast, corrosion inhibitors are gradually used up, and must be replenished from time to time. Larger systems (such as HVAC systems) are often monitored by specialist firms which take responsibility for adding corrosion inhibitors and regulating coolant composition. For simplicity, most automotive manufacturers recommend periodic complete replacement of engine coolant, to simultaneously renew corrosion inhibitors and remove accumulated contaminants.
Traditional inhibitors[edit]
Traditionally, there were two major corrosion inhibitors used in vehicles: silicates and phosphates. American made vehicles traditionally used both silicates and phosphates.[17] European makes contain silicates and other inhibitors, but no phosphates.[17] Japanese makes traditionally use phosphates and other inhibitors, but no silicates.[17][18]
Organic acid technology[edit]
Certain cars are built with organic acid technology (OAT) antifreeze (e.g., DEX-COOL[19]), or with a hybrid organic acid technology (HOAT) formulation (e.g., Zerex G-05),[20] both of which are claimed to have an extended service life of five years or 240,000 km (150,000 mi).
DEX-COOL specifically has caused controversy. Litigation has linked it with intake manifold gasket failures in General Motors' (GM's) 3.1L and 3.4L engines, and with other failures in 3.8L and 4.3L engines. One of the anti-corrosion components presented as sodium or Potassium 2-ethylhexanoate and ethylhexanoic acid is incompatible with nylon 6,6 and silicone rubber, and is a known plasticizer. Class action lawsuits were registered in several states, and in Canada,[21] to address some of these claims. The first of these to reach a decision was in Missouri, where a settlement was announced early in December 2007.[22] Late in March 2008, GM agreed to compensate complainants in the remaining 49 states.[23] GM (Motors Liquidation Company) filed for bankruptcy in 2009, which tied up the outstanding claims until a court determines who gets paid.[24]
According to the DEX-COOL manufacturer, "mixing a 'green' [non-OAT] coolant with DEX-COOL reduces the batch's change interval to 2 years or 30,000 miles, but will otherwise cause no damage to the engine".[25] DEX-COOL antifreeze uses two inhibitors: sebacate and 2-EHA (2-ethylhexanoic acid), the latter which works well with the hard water found in the United States, but is a plasticizer that can cause gaskets to leak.[17]
According to internal GM documents,[citation needed] the ultimate culprit appears to be operating vehicles for long periods of time with low coolant levels. The low coolant is caused by pressure caps that fail in the open position. (The new caps and recovery bottles were introduced at the same time as DEX-COOL). This exposes hot engine components to air and vapors, causing corrosion and contamination of the coolant with iron oxide particles, which in turn can aggravate the pressure cap problem as contamination holds the caps open permanently.[26]
Honda and Toyota's new extended life coolant use OAT with sebacate, but without the 2-EHA. Some added phosphates provide protection while the OAT builds up.[17] Honda specifically excludes 2-EHA from their formulas.
Typically, OAT antifreeze contains an orange dye to differentiate it from the conventional glycol-based coolants (green or yellow). Some of the newer OAT coolants claim to be compatible with all types of OAT and glycol-based coolants; these are typically green or yellow in color (for a table of colors, see[16]).
Hybrid organic acid technology[edit]
HOAT coolants typically mix an OAT with a traditional inhibitor, such as silicates or phosphates.
G05 is a low-silicate, phosphate free formula that includes the benzoate inhibitor.[17]
All automotive antifreeze formulations, including the newer organic acid (OAT antifreeze) formulations, are environmentally hazardous because of the blend of additives (around 5%), including lubricants, buffers and corrosion inhibitors.[27] Because the additives in antifreeze are proprietary, the safety data sheets (SDS) provided by the manufacturer list only those compounds which are considered to be significant safety hazards when used in accordance with the manufacturer's recommendations. Common additives include sodium silicate, disodium phosphate, sodium molybdate, sodium borate, denatonium benzoate and dextrin (hydroxyethyl starch). Disodium fluorescein dyes are added to antifreeze to help trace the source of leaks, and as an identifier since some different formulations are incompatible.[16]
Automotive antifreeze has a characteristic odor due to the additive tolytriazole, a corrosion inhibitor. The unpleasant odor in industrial use tolytriazole comes from impurities in the product that are formed from the toluidine isomers (ortho-, meta- and para-toluidine) and meta-diamino toluene which are side-products in the manufacture of tolytriazole.[28] These side-products are highly reactive and produce volatile aromatic amines which are responsible for the unpleasant odor.[29]
See also[edit]
1. ^ Prestone Press Release
2. ^ a b Peak Antifreeze chart Archived October 5, 2010, at the Wayback Machine.
3. ^ [1]
4. ^ a b c Brent J (2001). "Current management of ethylene glycol poisoning". Drugs. 61 (7): 979–88. doi:10.2165/00003495-200161070-00006. ISSN 0012-6667. PMID 11434452.
5. ^ "Antifreeze Warning". The Cat Fanciers' Association, Inc. Archived from the original on June 20, 2009. Retrieved 2007-05-15.
6. ^ Nash, Alanna. "The Black Widow Killer: Two men. Two murders. Too many questions.". Reader's Digest. Retrieved 2009-04-26.
7. ^ Munro, Ian (2007-10-13). "Death by anti-freeze 'perfect murder'". The Age. Retrieved 2009-04-25.
8. ^ a b Angela Chambers and Jon Meyersohn (2009-04-23). "Exhumed Body Reveals Stacey Castor's First Husband 'Didn't Just Die': Exclusive Look Inside Anti-Freeze Murder Mystery; What Brought Two Men to Rest in Neighboring Graves". ABC. Archived from the original on 25 April 2009. Retrieved 2009-04-25.
9. ^ Charles Loudon Bloxam (1873). Chemistry, inorganic and organic: with experiments (2 ed.). H.C. Lea. p. 587.
10. ^ Evaluation of Certain Food Additives and Contaminants (Technical Report Series). World Health Organization. p. 105. ISBN 92-4-120909-7.
11. ^ When an aqueous solution of propylene glycol in a cooling or heating system develops a reddish or black color, this indicates that iron in the system is corroding significantly. In the absence of inhibitors, propylene glycol can react with oxygen and metal ions, generating various compounds including organic acids (e.g., formic, oxalic, acetic). These acids accelerate the corrosion of metals in the system. See:
12. ^ Glycerol Freezing Point Archived February 27, 2012, at the Wayback Machine.
13. ^ Hudgens, R. Douglas; Hercamp, Richard D.; Francis, Jaime; Nyman, Dan A.; Bartoli, Yolanda (2007). "An Evaluation of Glycerin (Glycerol) as a Heavy Duty Engine Antifreeze/Coolant Base". doi:10.4271/2007-01-4000. Retrieved 2013-06-07.
14. ^ "Proposed ASTM Engine Coolant Standards Focus on Glycerin". Retrieved 2013-06-07.
15. ^ a b c Engine Cooling Testing: Why use a refractometer? Archived July 25, 2011, at the Wayback Machine. posted 2/7/2001 by Michael Reimer
16. ^ a b c Coolants Matrix 2003_5.xls. (PDF) . Retrieved on 2011-01-01.
17. ^ a b c d e f "Coolant Confusion: It's Not Easy Being Green ... or Yellow or Orange or ...". Retrieved 2013-06-07.
18. ^ "Coolant Confusion". Archived from the original on 2013-05-12. Retrieved 2013-06-07.
19. ^ Products: North America: Anti Freeze/Coolants. (2003-01-31). Retrieved on 2011-01-01.
20. ^ "Zerex G-05® Antifreeze / Coolant". Retrieved 2013-06-07.
21. ^ "Canadian Nationwide Class Action Settlement Agreement" (pdf). Retrieved 2013-06-07.
22. ^ Tentative Settlement of GM DEX-COOL Class Action Suit
23. ^ DEX-COOL Litigation Website
24. ^ "GM wants to dump liability for damaged engines in Dex-Cool cases". Retrieved 2013-06-07.
25. ^ MACS 2001: GM and Texaco "Bare All" about DEX-COOL. Retrieved on 2011-01-01.
26. ^ Draft—DEX 2007, Part 3: Now It’s All Up To The Judges and Juries. Retrieved on 2011-01-01.
27. ^ A safe and effective propylene glycol based capture liquid for fruit fly traps baited with synthetic lures – page 2|Florida Entomologist. Retrieved on 2011-01-01.
28. ^ VOGT, P. F. 2005. Tolytriazole-myth and misconceptions. The Analyst 12: 1–3.
29. ^ A safe and effective propylene glycol based capture liquid for fruit fly traps baited with synthetic lures; Florida Entomologist, June, 2008 by Donald B. Thomas |
Vice’s Guide to North Korea: Review
I remember going to the DMZ and being curious about what the experience would be like from the other side. Even though we saw documentaries during our internship about North Korea, they involved commonly photographed locations, like the stadium for extravagant displays of gymnastics and the theme park from hell. However, recently I saw the Vice Guide to North Korea online, and, though it made the same conclusions about the process of touring North Korea as a foreigner, it did highlight some different occasions, not to mention a funny host that livens up the grim locations. Here are some interesting locations and details they covered that I had not seen in other documentaries:
1. Getting into North Korea:
One of the details that I liked about the documentary was the way the host got into North Korea. First of all, it was pretty illegal. Or at the very least, under the table. After applying to get into North Korea through a variety of embassies and being turned down, a North Korean refugee gave him a tip-off about how to get in. She told him to go to China and bride an official to let him it, and soon enough he was in Pyongyang
2. Food situation:
As we saw in other documentaries, when you are a tourist in North Korea, you are shown only what the officials want you to see, and taken to fancy restaurants and hotels that are only used for tourists. A creepy, abandoned feeling is prevalent throughout the entire documentary. One moment was his first meal in his first hotel in Pyongyang. He is brought into a banquet hall where every place is set, but he is the only one eating. As he makes a comment about the hotel going out of their way to prove that there is no food shortage in North Korea, we can see the waitresses placing meals in front of all the set places, and then taking it all back to the kitchen.
3. Unification and Indoctrination:
During one of the trips of propaganda for the tourists, he asked a citizen if unification would happen. The citizen said of course, because North Korea was so great.
4. DMZ from the North.
Complete with a bunch of Chinese visitors, the DMZ from the North was exactly as I suspected. It was surprisingly easier to get to from the north than the south, probably because, if you’ve gotten that far, the government knows you’re there. Also, there were many more troops on hold from the north than the south, along with statues that the officials claimed were filled with explosives that would fall down to create tank blockades in case of an attack.
5. “The land that time forgot:”
The host of the documentary perfectly stated what I feel whenever studying North Korea—more than anything else, that it is lost in time, like a time capsule. The fact that there are official government mandated professors to answer any of your philosophical questions harks back to a time when there was little room for discussion for questions of morality. The footage of children playing music for the state was enlightening—the accordion playing children helped explain why my mentee at the Hangyore School raved about her accordion skills.
However, something major that this documentary was missing was hard facts about North Korea or any insight into the average life of a North Korean. Even though a tourist’s experience in North Korea is limited, I wish I could go there—even if only so that I could better connect with refugees in South Korea and to hear their experiences living and escaping from North Korea. One thing that the documentary did do for me was help me understand how cut off they are from the rest of the world, and how much energy the government puts into impressing the foreigners that they claim to not care about. I also had a hard time understanding before this video the pervasiveness of the government’s philosophy in its people. The people who were interviewed (maybe because they lived in Pyongyang and worked in the party) had an opinion that unwaveringly agreed with government propaganda. However, when you have heard nothing else your whole life, what would tell you to question it? I hope I can learn more about this from talking to defectors.
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"I Can!": Building students' self-efficacy
Research-based strategies to build students' self-efficacy
Elizabeth DeOrnellas
on 30 April 2011
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Transcript of "I Can!": Building students' self-efficacy
"I Can!": Building students' self-efficacy What is self-efficacy? One's belief in one's ability to succeed To develop self-efficacy, students must... Believe they have ALREADY
accomplished something Believe they CAN achieve WHY is this important? The psychologist Albert Bandura
found that self-efficacy affects: -How well people
acquire new skills
and knowledge -How well
people perform
on new tasks He also found that... self-efficacy beliefs were a better predictor
of future performance than
forecasting based on past results. So what? There is a role for praise in the classroom, BUT Teachers must be careful to praise EFFORT rather than INTELLIGENCE. Let's let Carol Dweck explain: Now remember, we have two goals: 1. Show students they CAN achieve. 2. Show students they have
ALREADY accomplished something. Dweck's theories on "process praise"
versus "intelligence praise" help
teachers accomplish that first goal. In other words...
Always praise students for
how hard they have worked,
NOT for how smart they are. That will cause students to develop a
GROWTH MINDSET that emphasizes a belief in
MALLEABLE INTELLIGENCE. Make this your classroom slogan: Intelligence is NOT fixed.
equals success. Now, how do I show students
that they've ALREADY
accomplished something? The best way to keep students motivated is to provide TIMELY,
CONSTRUCTIVE FEEDBACK through formative assessments. That strategy is called
"Assessment for Learning," and it can take many forms. The basic principles of
"Assessment for Learning" are as follows: 1. Give students multiple chances to master important skills. 2. Create a grading system
that rewards progress and
doesn't penalize students
for taking longer to reach
mastery. Here's an example of how
"Assessment for Learning"
might play out in the
real world: To avoid the problems
shown in the video,
create a grading system
that rewards students
for mastering concepts,
regardless of how long
they take to reach their goal. For example, you could allow
students to retake
important exams
an unlimited number
of times. That policy creates
an environment in which
the ultimate goal
is for the students to
demonstrate mastery
of the targeted skills,
no matter how many tries
it takes for them to reach that goal. There is much more that could be said about building self-efficacy in general
and "Assessment for Learning" in particular. For now, remember these principles:
1. Intelligence is NOT fixed.
HARD WORK plus perseverance
equals success. 2. Praise EFFORT, not intelligence. 3. Create a grading system
that rewards PROGRESS
and recognizes that the
ultimate goal should be for
students to achieve mastery,
regardless of how long
they take to reach their goal. Don't forget to create
a tracking system so that
students can visually see
their progress. Simple spreadsheets
or graphs can accomplish this goal.
Full transcript |
A Sister Blog of
Tasawwuf and Reform in the Late 19th Century India: The Significance of Ahmad Riza Khan’s (1856-1921) Role in the Defence of Sufism
Ahmad Riza Khan (d.1921), conventionally known as the leader of the twentieth century Ahl-e Sunnat wa Jama’at (people of the Sunna and the majority) to its followers and to others as the Barewli Movement[1], was an alim and sufi in British India. He was born a year before the civil and military revolt of 1857 and was traditionally educated by his father, Mufti Naqi Ali Khan (d.1880) at home in Bareilly, under whom he completed the Dars-e Nizami syllabus (Sufi 1941) studying a range of twenty-one Islamic sciences by the age of thirteen (Riza 2003: 54). In his licenses and Isnad certificates to the scholars of Makka and Madina in 1905, he claimed to have pursued an extensive spectrum of twenty eight sciences alone (Riza 2003: 58). He authored works in more or less everything he studied[2] some of which received compliments from leading Sunni scholars of Hijaz, Yemen, Syria and Egypt.[3]
Fatwa writing had become a major occupation of the Ulama at this period of time (Metcalfe 2006: 63). Ahmad Riza occupied most of his time in writing responses to people seeking guidance in religious, social, moral and political affairs which absorbed him to the very end of his life producing a bulky fatawa compendium in the Hanafi Law, now fully edited and indexed in thirty-three over sized volumes (Riza April 2006).[4]
Ahmad Riza was an authoritative author, gifted scholar of classical Islamic sciences both the rational (ma’qulat) and transmitted sciences (manqulat)[5] offering original contributions in nearly every field he studied, phenomenal Arabist, distinguished Mufti, and a genius in the pantheon of great thinkers and makers of the Muslim world[6] living in a period when Sufism was being rejected or rethought by reform movements both at home and abroad[7]. He never wavered from supporting what he believed to be Traditional Islam and remained mindful of the positions of his elders as he was not just a scholar of Law but also a committed student of a Sufi father and devout murid of the Barakatiyya Sayyids of Marahra[8], who followed the Qadiri path[9].
Ahmad Riza plays an imperative role as a Sufi in a particularly interesting juncture since from the late 18th century, not just Sufism but Islam as a whole was caught within the challenges of colonialism and modernity[10]. In this essay, I will seek to argue that, in the wake of religious reform in British India; Ahmad Riza’s works in defence of Sufism created the hallmark of Sunni identity, by bringing to light the importance of his understudied writings. In order to build upon this hypothesis, I will discuss the various tendencies towards Sufism[11] and shall present Ahmad Riza’s work on the issue of saintly intercession (tawassul) and practices affiliated with it, a prime example of debate at that time in the Subcontinent.
[1] Sanyal (1998: 635) notes that the differences of the names reflect an important point. By referring to themselves as the Ahl-e Sunnat wa Jama’at they place themselves within the mainstream of Sunni Muslim thought. However opponents from other movements called it Barelwi thereby that it is merely a local import, and by extension, deviant.
[2] A number of bibliographical surveys of Ahmad Riza’s books reveal that he authored somewhat a thousand books in some fifty sciences (Ahmad 1997: 39; Jabir 2007:51-73; Amjadi 1999: 3-4).
[3] For testimonials to al-Dawlah al-Makkiyyah, Ahmad Riza’s monograph on the Prophet’s knowledge of the unseen, see Riza (2001: 137-239). An example includes the chief Imam of the Mekkan Haram, Abul Khayr Mirdad who referred to Ahmad Riza as “the chief author of this era and by agreement of his contemporaries, the leader of writers” (Riza 2001: 149), a sign that Ahmad Riza’s writings had been circulating in the Hijaz during his life.
[4] For details on Ahmad Riza’s Fatwa writing see Sanyal (2005: 66-77) & Sanyal (1998: 643) in which she mentions that “the fatawa he wrote exceeded the work of ten muftis” and at anytime “there could be up to five hundred queries to be answered through mail”.
[5] The ma’qulat sciences are those based on human reasoning such as mathematics and logic, are contrasted with the manqulat such as those relating to the Quran and Hadith. The former was the hallmark of the scholars of Khairabad in particular and the latter was the specialty of the Delhi-based scholars particularly those affiliated with Madrasa-e Rahimiyya of Shah Wali Ullah (d.1762) (Sanyal 1998: 637).
[6] Oxford Oneworld series called “Makers of the Muslim world” includes Usha Sanyal’s comprehensive biography of Ahmad Riza Khan published in 2005 paying special tribute to his work and thought.
[7] Discussions on this area will follow with references.
[8] A town in the Etah district southwest of Bareilly.
[9] The family had settled in Marahra in the seventeenth century around the hospice (dargah) of Shah Barkat Ullah (1660-1729). (Sanyal 1998: 644, 647: 2005; 62) Qadiri documented a history of the family in his Khandan-e Barakat (1927).
[10] For discussions on Colonialism in India, see Metcalfe (2006).
[11] Sirriyeh develops this area well in Sufis and Anti-Sufis: The Defence, Rethinking and Rejection of Sufism in the Modern World (1999).
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Space Science
Astronomers Discover the Coolest Known Sub-Stellar Body 60
Hugh Pickens writes "Science Daily reports that using the United Kingdom Infrared Telescope (UKIRT) in Hawaii, astronomers have discovered what may be the coolest sub-stellar body ever found outside our own solar system. Too small to be stars and with insufficient mass to maintain hydrogen-burning nuclear fusion reactions in their cores, 'brown dwarfs' have masses smaller than stars but larger than gas giant planets like Jupiter, with an upper limit in between 75 and 80 Jupiter masses. 'This looks like the fourth time in three years that the UKIRT has made a record breaking discovery of the coolest known brown dwarf, with an estimated temperature not far above 200 degrees Celsius,' says Dr. Philip Lucas at the University of Hertfordshire. Due to their low temperature these objects are very faint in visible light, and are detected by their glow at infrared wavelengths. The object known as SDSS1416+13B is in a wide orbit around a somewhat brighter and warmer brown dwarf, SDSS1416+13A, and the pair is located between 15 and 50 light years from the solar system, which is quite close in astronomical terms."
Astronomers Discover the Coolest Known Sub-Stellar Body
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What is a Bed Turning?
Have you ever wondered, "just what is a Bed Turning anyway"?
Bed Turning demonstrations are showing up lately at quilt shows around the country. It is a unique way of telling the stories and history of of quilts in a cozy kind of way.
Quilts have a long history of not only being used for warmth, but are also considered a form of art. They are a pictoral history of the lives and experiences as told from the Quilter themselves.
In the distant past the Quilter would use a Bed Turning as a social event. Some tell the story that a lady would invite several guests over and serve sweet tea and cookies, then show off the quilts she had made by layering several of them on a bed.
Today, Bed Turnings can be seen at quilting events in themed groupings, or chronologically to appreciative audiences who are intrigued with the stories the quilts can tell. |
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Submission + - Save the Ozone layer, heat the planet
Control Group writes: According to, the law of unintended consequences has struck the Ozone-layer preserving Montreal Protocol. While the treaty has been successful in reducing the use of Ozone-depleting CFCs, it turns out that their hydrofluorocarbon (HFC) and hydrochlorofluorocarban (HCFC) replacements are massive greenhouse gases. "Use of HCFCs and HFCs is projected to add the equivalent of 2 billion to 3 billion tons of carbon dioxide emissions to the atmosphere by 2015, U.N. climate experts said in a recent report." For comparison's sake, even were the Kyoto treaty to be embraced worldwide, its target is to reduce CO2 emissions by roughly 1 billion tons by 2012. The same report recommends the use of greenhouse-friendlier replacements such as ammonia, hydrocarbons, or CO2, but industry cites concerns about these substances: the safety of hydrocarbon cooling (mainly using propane), along with reduced energy efficiency.
"If there's a leak in a residential line, it can ignite — you have a potential bomb," said Stephen Yurek, general counsel for the Air-Conditioning and Refrigeration Institute. It represents North American makers of equipment for homes, businesses and transportation.
Manufacturers also say they could not meet U.S. energy efficiency requirements that took effect this year if they used those chemicals. "The technology just isn't there," Yurek said. "
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Calculus Extra Credit1
Calculus Extra Credit1 - Extra Credit- Chaos Theory The...
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Unformatted text preview: Extra Credit- Chaos Theory The lecture involved a historical perspective on calculus, an explanation of the Newtonian worldview, and a look into chaos theory. Rationalism prevailed during the 17 th century, but math had been developing long before then. Around 300 B.C., Greeks were working with circles and drawing polygons in it to find the area. By the 1600s, people worked with tangent lines and integrals. In 1655, Newton formalizes calculus but never publishes his work. So, in 1680s, when Leibniz formalizes calculus, Newton claims that Leibniz stole calculus from him. The Royal Society, a group of elite scientists in England, ruled in favor of Newton, which stifled mathematic progress in England for 200 years because they closed off interactions with the rest of the European academic world. A German mathematician, Mencke, contributed significantly to mathematics. He established a journal published in German, a move away from mathematics communicated in Latin, and in the process bolsters rationalism by testing concepts...
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This chapter is from the book
This chapter is from the book
1. Does a gasoline engine have a single point of failure? Does a motorized fire engine? Does a fire department? How does each of the last two compensate for single points of failure in the previous one(s)? Explain your answers.
2. Telecommunications network providers and users are concerned about the single point of failure in "the last mile," which is the single cable from the network provider's last switching station to the customer's premises. How can a customer protect against that single point of failure? Comment on whether your approach presents a good cost-benefit trade-off.
3. You are designing a business in which you will host companies' web sites. What issues can you see as single points of failure? List the resources that could be involved. State ways to overcome each resource's being a single point of failure.
4. The human body exhibits remarkable resilience. State three examples in which the body compensates for failure of single body parts.
5. How can hardware be designed for fault tolerance? Are these methods applicable to software? Why or why not?
6. The old human telephone "switches" were quaint but very slow. You would signal the operator and say you wanted to speak to Jill, but the operator, knowing Jill was visiting Sally, would connect you there. Other than slowness or inefficiency, what are two other disadvantages of this scheme?
7. An (analog) telephone call is "circuit based," meaning that the system chooses a wire path from sender to receiver and that path or circuit is dedicated to the call until it is complete. What are two disadvantages of circuit switching?
8. The OSI model is inefficient; each layer must take the work of higher layers, add some result, and pass the work to lower layers. This process ends with the equivalent of a gift inside seven nested boxes, each one wrapped and sealed. Surely this wrapping (and unwrapping) is inefficient. From reading earlier chapters of this book, cite a security advantage of the layered approach.
9. Obviously, the physical layer has to be at the bottom of the OSI stack, with applications at the top. Justify the order of the other five layers as moving from low to high abstraction.
10. List the major security issues dealt with at each level of the OSI protocol stack.
11. What security advantage occurs from a packet's containing the source NIC address and not just the destination NIC address?
12. TCP is a robust protocol: Sequencing and error correction are ensured, but there is a penalty in overhead (for example, if no resequencing or error correction is needed). UDP does not provide these services but is correspondingly simpler. Cite specific situations in which the lightweight UDP protocol could be acceptable, that is, when error correction or sequencing is not needed.
13. Assume no FTP protocol exists. You are asked to define a function analogous to the FTP PUT for exchange of files. List three security features or mechanisms you would include in your protocol.
14. A 32-bit IP addressing scheme affords approximately 4 billion addresses. Compare this number to the world's population. Every additional bit doubles the number of potential addresses. Although 32 bits is becoming too small, 128 bits seems excessive, even allowing for significant growth. But not all bits have to be dedicated to specifying an address. Cite a security use for a few bits in an address.
15. Sidebar 7-1 on usage of the University of Illinois site states that on a particular day, the site had been visited by hosts in 57 different countries. How do they know? Describe a means that an attacker could make it seem as if there were accesses from 57 countries. In your answer, cover both an actual number smaller than 57 and greater than 57. (You may treat these two cases separately.)
16. When a new domain is created, for example, yourdomain.com, a table in the .com domain has to receive an entry for yourdomain. What security attack might someone try against the registrar of .com (the administrator of the .com table) during the creation of yourdomain.com?
17. Describe a social engineering attack you could use to obtain a user's password.
18. Is a social engineering attack more likely to succeed in person, over the telephone, or through e-mail? Justify your answer.
19. A port scanner is a tool useful to an attacker to identify possible vulnerabilities in a potential victim's system. Cite a situation in which someone who is not an attacker could use a port scanner for a nonmalicious purpose.
20. One argument in the security community is that lack of diversity is itself a vulnerability. For example, the two dominant browsers, Netscape Navigator and Microsoft Internet Explorer, are used by probably 95 percent of Internet users. What security risk does this control of the market introduce? Suppose there were three (each with a significant share of the market). Would three negate that security risk?
21. Compare copper wire, microwave, optical fiber, infrared, and (radio frequency) wireless in their resistance to passive and active wiretapping.
22. How many 4-digit numeric PINs are there? Suppose a ban prohibits "obvious" PINs like 0000 and 1234. What would you define as "obvious," and how many PINs would that disallow? Now assume people choose PINs not for their numeric significance but because they are all or the first four letters of a word as on a telephone keypad: A,B,C=2, D,E,F=3, etc. Using the cryptanalysis lessons from Chapter 2, estimate how many 4-digit PINs that people might choose would really exist. The goal of this exercise is not to obtain the definitive answer but to present a reasonable analysis. In what network settings is a PIN still justified as an authenticator, in spite of the small numbers you obtain in this exercise?
23. What is a "man-in-the-middle" attack? Cite a real-life example (not from computer networking) of such an attack. Suggest a means by which sender and receiver can preclude a man-in-the-middle attack. (a) Cite a means not requiring cryptography. (b) Cite a means involving cryptography but also ensuring that the man in the middle cannot get in the middle of the key exchange.
24. Suggest a countermeasure for traffic flow analysis.
25. A problem with pattern matching is synonyms. If the current directory is bin, and . denotes the current directory and .. its parent, then bin, ../bin, ../bin/., .././bin/../bin all denote the same directory. If you are trying to block access to the bin directory in a command script, you need to consider all these variants (and an infinite number more). Cite a means by which a pattern-matching algorithm copes with synonyms.
26. The HTTP protocol is by definition stateless, meaning that it has no mechanism for "remembering" data from one interaction to the next. (a) Suggest a means by which you can preserve state between two HTTP calls. For example, you may send the user a page of books and prices matching a user's query, and you want to avoid having to look up the price of each book again once the user chooses one to purchase. (b) Suggest a means by which you can preserve some notion of state between two web accesses many days apart. For example, the user may prefer prices quoted in euros instead of dollars, and you want to present prices in the preferred currency next time without asking the user.
27. How can a web site distinguish between lack of capacity and a denial-of-service attack? For example, web sites often experience a tremendous increase in volume of traffic right after an advertisement with the site's URL is shown on television during the broadcast of a popular sporting event. That spike in usage is the result of normal access that happens to occur at the same time. How can a site determine that high traffic is reasonable?
28. Syn flood is the result of some incomplete protocol exchange: The client initiates an exchange but does not complete it. Unfortunately, these situations can also occur normally. Describe a benign situation that could cause a protocol exchange to be incomplete.
29. A distributed denial-of-service attack requires zombies running on numerous machines to perform part of the attack simultaneously. If you were a system administrator looking for zombies on your network, what would you look for?
30. Signing of mobile code is a suggested approach for addressing the vulnerability of hostile code. Outline what a code-signing scheme would have to do.
31. The system must control applets' accesses to sensitive system resources, such as the file system, the processor, the network, and internal state variables. But the term "the file system" is very broad, and useful applets usually need some persistent storage. Suggest controls that could be placed on access to the file system. Your answer has to be more specific than "allow all reads" or "disallow all writes." Your answer should essentially differentiate between what is "security critical" and not, or "harmful" and not.
32. Suppose you have a high-capacity network connection coming into your home, and you also have a wireless network access point. Also suppose you do not use the full capacity of your network connection. List three reasons you might still want to prevent an outsider from obtaining free network access by intruding into your wireless network.
33. Why is segmentation recommended for network design? That is, what makes it better to have a separate network segment for web servers, one for the back-end office processing, one for testing new code, and one for system management?
34. For large applications, some web sites use devices called "load balancers" to distribute traffic evenly among several equivalent servers. For example, a search engine might have a massive database of content and URLs, and several front-end processors that formulate queries to the database manager and format results to display to an inquiring client. A load balancer would assign each incoming client request to the least busy processor. What is a security advantage of using a load balancer?
35. Can link and end-to-end encryption both be used on the same communication? What would be the advantage of that? Cite a situation in which both forms of encryption might be desirable.
36. Does a VPN use link encryption or end-to-end? Justify your answer.
37. Why is a firewall a good place to implement a VPN? Why not implement it at the actual server(s) being accessed?
38. Does a VPN use symmetric or asymmetric encryption? Explain your answer.
39. Does a PKI perform encryption? Explain your answer.
40. Does a PKI use symmetric or asymmetric encryption? Explain your answer.
41. Should a PKI be supported on a firewall (meaning that the certificates would be stored on the firewall and the firewall would distribute certificates on demand)? Explain your answer.
42. Why does a PKI need a means to cancel or invalidate certificates? Why is it not sufficient for the PKI to stop distributing a certificate after it becomes invalid?
43. Some people think the certificate authorities for a PKI should be the government, but others think certificate authorities should be private entities, such as banks, corporations, or schools. What are the advantages and disadvantages of each approach?
44. If you live in country A and receive a certificate signed by a government certificate authority in country B, what conditions would cause you to trust that signature as authentic?
45. A certificate contains an identity, a public key, and signatures attesting that the public key belongs to the identity. Other fields that may be present include the organization (for example, university, company, or government) to which that identity belongs and perhaps suborganizations (college, department, program, branch, office). What security purpose do these other fields serve, if any? Explain your answer.
46. What is the security purpose for the fields, such as sequence number, of an IPSec packet?
47. Discuss the trade-offs between a manual challenge response system (one to which the user computes the response by hand or mentally) and a system that uses a special device, like a calculator.
48. A synchronous password token has to operate at the same pace as the receiver. That is, the token has to advance to the next random number at the same time the receiver advances. Because of clock imprecision, the two units will not always be perfectly together; for example, the token's clock might run 1 second per day slower than the receiver's. Over time, the accumulated difference can be significant. Suggest a means by which the receiver can detect and compensate for clock drift on the part of the token.
49. The workstation is a weak link in systems like PKI and Kerberos: A compromised workstation can collect and transmit cleartext passwords and encryption keys. Suggest a means to prevent compromise of a workstation from, for example, a Trojan horse.
50. This chapter listed several disadvantages to ACLs on routers as a network access control method. List two advantages.
51. List a situation in which you might want to block (reject) certain traffic through an ACL on a router; that is, a situation in which the performance penalty would not be the deciding factor.
52. What information might a stateful inspection firewall want to examine from multiple packets?
53. Recall that packet reordering and reassembly occur at the transport level of the TCP/IP protocol suite. A firewall will operate at a lower layer, either the Internet or data layer. How can a stateful inspection firewall determine anything about a traffic stream when the stream may be out of order or damaged?
54. Do firewall rules have to be symmetric? That is, does a firewall have to block a particular traffic type both inbound (to the protected site) and outbound (from the site)? Why or why not?
55. The FTP protocol is relatively easy to proxy; the firewall decides, for example, whether an outsider should be able to access a particular directory in the file system and issues a corresponding command to the inside file manager or responds negatively to the outsider. Other protocols are not feasible to proxy. List three protocols that it would be prohibitively difficult or impossible to proxy. Explain your answer.
56. How would the content of the audit log differ for a screening router versus an application proxy firewall?
57. Cite a reason why an organization might want two or more firewalls on a single network.
58. Firewalls are targets for penetrators. Why are there few compromises of firewalls?
59. Should a network administrator put a firewall in front of a honeypot? Why or why not?
60. Can a firewall block attacks using server scripts, such as the attack in which the user could change a price on an item offered by an e-commerce site? Why or why not?
61. Why does a stealth mode IDS need a separate network to communicate alarms and to accept management commands?
62. One form of IDS starts operation by generating an alert for every action. Over time, the administrator adjusts the setting of the IDS so that common, benign activities do not generate alarms. What are the advantages and disadvantages of this design for an IDS?
63. Can encrypted e-mail provide verification to a sender that a recipient has read an e-mail message? Why or why not?
64. Can message confidentiality and message integrity protection be applied to the same message? Why or why not?
65. What are the advantages and disadvantages of an e-mail program (such as Eudora or Outlook) that automatically applies and removes protection to e-mail messages between sender and receiver?
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Crime and Punishment
Crime Prevention 1450-1750 Main page
Game Print Sources Print Sources Print Sources
Did methods of crime prevention change in the period 1450-1750?
We are used to living in a time of change; new technology and new ideas re-make the world we live in every few years. But history has not always been like this. Sometimes things remained the same for decades, even centuries. So it was with crime prevention in this period.
No new jobs were created. The main local officials responsible for crime prevention -Justices of the Peace and petty constables - had been set up in the Middle Ages.
Why should they change? Monarchs found JPs useful and gave them more work to do: one 16th century JP complained of "stacks of statutes". JPs had the great advantage, to the government, of being unpaid. For their part, they liked the power and the prestige of running their locality. Petty constables were also unpaid, chosen from the people in a community to do the job for a year. This legal system matched the social system: JPs were more important, petty constables were among the more established villagers.
This is not to say that England did not change in these centuries. The population tripled, but it was still a country of small towns and vilages, as it was in medieval times. The 15th century baronial wars known as the Wars of the Roses, and the 17th century Civil War, meant that the country was highly suspicious of soldiers and loathed the idea of a special force of lawmen. This left a large part of crime prevention up to the individual. If you were robbed, you had to find out who did it and take the person to court yourself.
One effect of this lack of change is that there are fewer exhibits to put in this Section of the Gallery.
There is only one Case-Study:
Complaints and Criticisms
Source 1 Source 2 Source 4 Source 3 Case Study 4 The Growth of the police Case Study 5 Complaints and Criticisms Case Study 2 Justice of the Peace Case Study 3 Provincial police forces Case Study 1 Constables and the Watch to Crime Prevention 1750-1900 to Crime Prevention before 1450 Case Studies to Crime 1450-1700 to Punishment 1450-1750 |
Mobile Programming
This lesson is part of the Mobile for OutSystems Developers course.
Welcome to debugging. In this session
we'd like to discuss the approaches and the tools that we might use to debug our
mobile applications. Different parts of our mobile applications will actually
require different approaches to the debugging. For our server actions which
will be running on the server side will be doing traditional debugging will be
able to set breakpoints control execution flows on the server and
inspect the variables that are there, and we do that from the normal development
environment, so we have the typical tools we might expect there. We also need to be
able to debug some of the logic running on the client side so for that we can
use Chrome Dev Tools while we're working in the emulator we can go ahead and be
able to see more information things coming back both in the console look at
the source of the JavaScript that's available there and get more information
about the network and the application itself. To be able to debug some of these
actions and find where the OutSystems resources are we have a shortcut to be
able to do that and we can also control some of the network capabilities to see
how things will work like offline and then if we do have offline we may have
local storage so we may want to be able to see those resources as well so we're
going to talk about all those capabilities now we also may want to
physically debug the code running in the device and there's ways to do that as
well so instead of just using an emulator we can get to the device there
is documentation available and will point you to that
so let's start with the server-side debugging. On the server side we can
place break points on elements and from their mobile applications we will have
different types of server actions and we'll be able to place the breakpoints
on those server actions. Now to be able to actually do the debugging we need to
start the debugger and this will enable the debugger to register all of the
breakpoints and then
pause the execution of the code whenever we get to one of those breakpoints, and
if we wanted to be able to see we can go to the debugger tab to get more
information about the debugging including the list of break points that
are currently there and from there we could remove the breakpoints we could
disable the breakpoints a lot of nice things to be able to see where the
breakpoints are going to be. Once we stop at a breakpoint down in the debug tab
there are different types of commands that will allow us to control the
execution flow. We can either just stop debugging completely we could abort this
given request we could let this request continue and run on, or if we wanted to
take a more controlled approach we could step over this particular component or
we could step into this particular component so we can step over step into
or if we're in something step out of, and then we can also ask it to break on all
errors so any type of error that we get we'd like to stop because we might want
to go back and be able to inspect some of the variables and do that
so where would we see those well in the debugger tab at the bottom of the
breakpoints will be to our left but here underneath the main parts of the tabs
will be able to see all the variables that are currently in use all of the
local variables any variables tied to widgets any variables that are from the
session or from site and any variables that we put on watches. Now a number of
these are actually used for normal web applications and not all these will
apply to our mobile but we will be able to see the ones and use local and
use the tabs to get more information about the variables and you can see that
the controls that we mentioned are here as well so everything is in the debug tab
together at the bottom of the screen. Now you may have noticed in the previous
screen that when we said we were going to start the debugger it said start the
debugger in the public area and by default whenever we start the debugger
it will start debugging in the public area and that means that it will start
debugging the app
where it's located and that would be on our server and if the app is called MyApp
it will be at MyApp now what that means is that if I place breakpoints
there and there are two or three of us working together on that app if you
begin trying to test the app then those breakpoints are going to apply and it's
going to jump you into the debug mode and you may not want to do that so if I
know there are other people working and I only want to debug things I'm working
on myself and not slow any of those people down I can debug in a personal
area so what will happen there is that the code will be regenerated placed into
MyApp and then your developer login and that way you'll be able to
debug the development that you're working on and it won't
affect any of the other people. So that's pretty nice it not going to impact the
main version it's going to let you do your changes more quickly so that's
fairly nice. Now if you make changes to the actual data model you have to
republish all of the code for the public area and then go
back into the personal area but the only way you can get to the run and debug in
your personal area is from the Debug menu at the top of our development
environment, and one other thing to think about is when we talked earlier
about having applications that have multiple modules by default breakpoints
stop the execution of requests to the module so if we have MyApp breakpoints
and were inside of MyApp, and we're testing it while we're testing MyApp,
the MyApp, breakpoints will will pause the execution and allow us to do our
debugging. If we don't have this particular app, we're not working in this
module to start with we know that we're going to be in another module but we
want to be able to stop the execution for this module's code
then what we can do is set the entry module for that particular set of
code and what that tells the debugger to do is attach to the instance of the code
that is running within the context of the consumer module so here were inside
of OSMDb_Core but we're asking it to start OSMDb so now someone would be
able to navigate to OSMDb and as they're going through that anytime OSMDb uses
the Core we will activate those breakpoints and be able to break at that
place. So when we have multiple modules we may need to be careful as to which
one we're selecting for the entry module to be able to get to the breakpoints in
the way we want to get to them. So this is all on the server side we also need to
be able to go ahead and handle things on the client side, so in this particular
case what we really say when we're debugging is will be debugging inside of
the browser and the browser running an emulator so for our mobile devices we
can go ahead and select the mobile device and the emulator we'll go ahead
and place the circle and that will basically be our touch so we have
touch-enabled emulators that should be able to give us the same type of
information that we might get from the device and here you can see the touch is
enabled in a way where I'm actually sliding using a gesture sliding our
sidebar from the left-hand side over and then going ahead and and letting it go
to do some searches so we do have the capability of having the touch-enabled
stuff and when we come to do any of the different types of work we can always
take any of the resources that are there and inspect them so if we right-click on
the star and we want to see something more about the star we could go ahead
and inspect that and inspecting this will bring up Chrome's Developer Tools
so we say we're using the emulator in the browser we need to be using the
browser to be able to do this type of client-side debugging because we're
going to be using Chrome Developer Tools so you can open the Developer Tools from
the menu at the top, saying that you would just like more tools and Developer
Tools or you can just go to any resource that's in the device in the emulator and
right click on it and say inspect. Now when we do that if we ask it to
inspect the gold star that is near the test device camera it will open the
Chrome developer tools and here you can see on the right-hand side it has opened
up the Chrome developer tools and it's actually tracking the fact that we're
working with the gold star so we can see that there's a link on the gold star
here is the icon that it's actually using and how it's displaying
it so up at the top we can see the actual elements we can see the styles
that are applied to it and down below in the console we can see information about
the requests and other things that are going on. So Chrome developer tools are
really nice because it can give us all this information about the JavaScript
that we're running inside the device now one of the things that can be a bit
problematic is that we're in a browser running an emulator and we want to see
all of this other information so you can leave it docked on the right-hand side
you could dock it at the bottom depending on the size of your screen you
may want to actually undock the window and keep the tools in a separate window.
They'll still react to whatever is happening inside of the device but we
would be able to have more real estate to see what's going on
so if we did that we'd still be able to see everything that's in the other
window and now we have a lot more space to be able to see the elements that are
there the styles that are available and things like that.
Now one thing you may have noticed down in the console is it says that if we
want to debug a client action then we should hold down the CTRL key while
using the app, and if we want to debug server actions we can just add break
points to any of the
server actions in Service Studio so we already talked about all the server
actions and server-side debugging, but here we can actually debug a client
action by holding down the CTRL key so what we might do there is we might
come over to our gold star place the touch there and use the CTRL key and
click it and if we click the CTRL key over the gold star what we'll see is
that the StarOnClickAction will be activated. The StarOnClickAction is
what goes ahead and changes the state of the star and stores that in the database
so we can go ahead and open that up and when we open it up it stops at the
debugger line, and at the debugger line it basically says at this point you're
near the StarOnClick capability and this below is all the things that it
needs to do, and at that point we can come up and we can step over each piece
of this JavaScript we can step into things that might be other functions in
other areas we can come back out of it or we can just continue letting the
script run as it started. So we can do all those things which are pretty cool
now some JavaScript can get fairly complicated and when it starts getting
complicated it's difficult to read
so what we may want to do is actually create or ask for the pretty version of
these files so you can either do that by clicking this little set of brackets at
the bottom or asking for the pretty minified file and it will open another tab
and it will shift everything and try to make the code look as easy as possible
to be able to read and follow so here it's a little bit quicker and easier to
see that this is the StarOnClickAction and here are all the things that
are related and contained inside of that action so lots of nice ways of being
able to see what's going on if we need to get down to the JavaScript level. Now
the JavaScript that we're looking at here is
the sources tab so the console is duplicated down here at the bottom
before we were inspecting the elements and now we're looking at the source and
in this particular case it tells you that we're looking at the ToDo main
source so the MainFlow has some source and we may want to be able to see where
that is so if we came over to the left hand side this is a list of all of the
sources. These sources that we're looking at right now are actually in the
contents of our ToDos, so the contents of the frame and what's happening are all
there inside of the ToDo if we wanted to go ahead and inspect those further we
could go to the server that we're on open the ToDos that we're looking for
and then go down to the script, and as we get down to the scripts there will be a
very large number of scripts because there are things here for buttons and
button groups because we're using those so each different widget and component
that we're using will have a JavaScript file here including things like the
plugins, so we have the capability of using the camera plugin and you can see
that here as well so there are a large list of these and if we wanted to see
where ToDo main is, we would just scroll down and be able to find ToDo main but
it's a little quicker and easier to go ahead and find the action just hit CTRL
click and jump into it. So here we can see the sources and be able to see all
the things that we need from a JavaScript perspective. If we also want
to be able to control the network maybe do some offline testing or be able to
see how this might work if we're going to bad network connection, Chrome
dev tools does a really nice job of either letting us know we're offline so
if we check offline and we make another request the phone will be notified that
it's offline and then it can change its behavior and attempt to react to that we
also can use this networking area to go ahead and see what different network
connections might look like so here there's no throttling if we go ahead and
make a request it shows us how long it takes
and it says that to load all the DOM it took a second and overall it took a
little more than two seconds.
Well what if we wanted to go ahead and say you know what instead of maybe
having a full-blown Wi-Fi connection or 4G connection with no throttling what
happens if i only have a 3G connection?
Well having a 3G connection connection takes a little bit longer and
takes almost three seconds to load so it begins
simulating and showing us each of the different resources that needs to be
loaded and how long it took, so here we needed 216 requests and they're only 76 KB
to go ahead and load over that time. Now that gives us a lot of information
about the JavaScript, we can sort of set breakpoints and move along the different
types of JavaScript we can look at the network connections, but we said we also
could test offline and for testing offline
could we see what's in local storage? The answer is yes. If we go to the
applications tab and look down inside of storage there is something called local
storage but that isn't where were storing our local storage entities so
this is a local storage that has different types of information inside of
similar more toward how its stores session information, so that's all
browser related and devtools related for us the the data that we actually want is
in the WebSQL that's where the local storage entities are so here you can see
our ToDo application and the ToDo has several different tables so if we go
down and look at the actual ToDo table we can see the five ToDos that were being
stored locally and being shown inside of our device, so this is one way where we
know what the different tables are and it will show us the list of tables and
we can just go look at one of those, but instead of having something simple like
five ToDos is we may have thousands of rows of data
well what could we do there if you go up to the top of the app and ask it you can
go ahead and give it a regular SQL query so here we know that the ToDos
are in this particular table so we could say select * from that table and we
all the data back we would have got that by just clicking on it but we can make a
much more involved SQL query to get a subset of the data to come back to us.
So we have access to local storage as well so dev tools is pretty cool
we have the capability of seeing a lot of the different parts of our mobile app
and getting more information about it, but this is still all in devtools and
it's still in the emulator what if we want to debug code actually running in
the device
well OutSystems 10 documentation has a section called debug code running in the
device and it goes into how we can look at the screens the different types of
actions and logic and look at local storage by actually connecting Chrome or
Safari and making sure that when it connects to the device we have the
capability of seeing more info, so again in this case we'd be using the Chrome
devtools just like we talked about with the emulator but the only difference is
now we use the Chrome devtools connected to the device to be able to see more, and
a lot of times we want to we may want to be able to do that to try to get a
better idea of what's going on with local storage because that's probably
the only easy way to be able to see what's going on. Now there's also other
types of problems that can come up that we may need to debug, if we're working
with mobile plugins and we might have one of the ones that supported by OutSystems
and its built-in we could go ahead and begin troubleshooting or
debugging that with OutSystems Now and if you've created your own plugins or
you want to be able to actually get down to the native code level because you're
having some sort of crash you need to go ahead and create a debug or dev build
of your mobile app and then use something like XCode or Android Studio
to go ahead and see that information. So in this section we gave sort of a
high-level overview of when we have mobile apps their server actions so we
have to use the server-side debugging that we would typically use, if we want
to be able to see more about the client-side Chrome devtools gives us
lots of great capabilities to
look at different things from the JavaScript itself and and step through
it to the network to the local storage so hopefully this gets you started and
you'll be able to learn more and debug more about your applications as you move |
Andrew Jackson
Political and Military Career
What were Jackson’s first political positions?
In 1796, he was selected as a delegate to the Tennessee Constitutional Convention, the body that created the Tennessee Constitution and established Tennessee as the sixteenth state in the United States. Later that year, he became a member of the U.S. House of Representatives, and in 1797 was elected to the U.S. Senate. He left the Senate after only one year and successfully ran for a position on the Tennessee Superior Court.
Currier & Ives created this artistic rendition of General Jackson leading troops in the Battle of New Orleans, which actually occurred after the end of the War of 1812.
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Articles on pcos
Things You Should Know About Polycystic Ovary Syndrome (Pcos)
Dr. Jyotsna Gupta, Gynecologist/Obstetrician
What is Polycystic Ovarian Disease (PCOD) or Polycystic Ovary Syndrome (PCOS)?Polycystic ovary syndrome (PCOS) is a health problem that can affect a woman's:Menstrual cycleAbility to have childrenAppearanceHormonesBlood vesselsHeartWith PCOS/PCOD women typically have:High levels of 'androgens.' These are sometimes called male hormones, though females also make them.Many small cysts (fluid-filled sacs) in their ovariesMissed or irregular periods (monthly bleeding)What causes PCOS? The cause of PCOS is unknown. But most experts think that several factors, including genetics, could play a role. Women with PCOS are more likely to have a mother or sister with PCOS.A main underlying problem with PCOS is a hormonal imbalance. In women with PCOS, the ovaries make more androgens than normal. Androgens are male hormones that females also make. High levels of these hormones affect the development and release of eggs during ovulation.High androgen levels can lead to:AcneExcessive hair growthWeight gainProblems with ovulation How many women have PCOS? Between 1 in 10 and 1 in 20 women of childbearing age has PCOS. It can occur in girls as young as 11 years old. What are the symptoms of PCOD or PCOS? The symptoms of PCOS can vary from woman to woman. Some of the polycystic ovary syndrome symptoms include:Infrequent, absent, and/or irregular menstrual periodsInfertility (not able to get pregnant) because of not ovulating. In fact, PCOS is the most common cause of female infertility.Increased hair growth on the face, chest, stomach, back, thumbs, or toesMale-pattern baldness or thinning hairCysts on the ovariesAcne, oily skin, or dandruffWeight gain or obesity, usually with extra weight around the waistSkin tags — excess flaps of skin in the armpits or neck areaPelvic painAnxiety or depressionPatches of skin on the neck, arms, breasts, or thighs that are thick and dark brown or blackSleep apnea — when breathing stops for short periods of time while asleepHow do I know if I have PCOS? There is no single test to diagnose PCOS. Your doctor will take the following steps to find out if you have PCOS or if something else is causing your symptoms.Medical history. Your doctor will ask about your menstrual periods, weight changes, and other symptoms.Physical exam. Your doctor will want to measure your blood pressure, body mass index (BMI), and waist size. He or she also will check the areas of increased hair growth. You should try to allow the natural hair to grow for a few days before the visit.Pelvic exam. Your doctor might want to check to see if your ovaries are enlarged or swollen by the increased number of small cysts.Blood tests. Your doctor may check the androgen hormone and glucose (sugar) levels in your blood.Ultrasound (sonogram). Your doctor may perform a test that uses sound waves to take pictures of the pelvic area. It might be used to examine your ovaries for cysts and check the endometrium (lining of the womb). This lining may become thicker if your periods are not regular.How is PCOS treated?Because there is no cure for PCOS, it needs to be managed to prevent problems. Treatment goals are based on your symptoms, whether or not you want to become pregnant, and lowering your chances of getting heart disease and diabetes. Many women will need a combination of treatments to meet these goals. Some treatments for PCOS include:Lifestyle modification. Many women with PCOS are overweight or obese, which can cause health problems. You can help manage your PCOS by eating healthy and exercising to keep your weight at a healthy level. Healthy eating tips include:Limiting processed foods and foods with added sugarsAdding more whole-grain products, fruits, vegetables, and lean meats to your dietThis helps to lower blood glucose (sugar) levels, improve the body's use of insulin, and normalize hormone levels in your body. Even a 10 percent loss in body weight can restore a normal period and make your cycle more regular.Birth control pills. For women who don't want to get pregnant, birth control pills can:Control menstrual cyclesReduce male hormone levelsHelp to clear acneFertility medications. Lack of ovulation is usually the reason for fertility problems in women with PCOS. Several medications that stimulate ovulation can help women with PCOS become pregnant. Even so, other reasons for infertility in both the woman and man should be ruled out before fertility medications are used.Another option is in vitro fertilization (IVF). IVF offers the best chance of becoming pregnant in any given cycle. It also gives doctors better control over the chance of multiple births. But, IVF is very costly.Surgery. "Ovarian drilling" is a surgery that may increase the chance of ovulation. It’s sometimes used when a woman does not respond to fertility medicines. This surgery can lower male hormone levels and help with ovulation. But, these effects may only last a few months.Medicine for increased hair growth or extra male hormones. Medicines called anti-androgens may reduce hair growth and clear acne. Anti-androgens are often combined with birth control pills. These medications should not be taken if you are trying to become pregnant.Before taking any Medicines tell your doctor if you are pregnant or plan to become pregnant. Do not breastfeed while taking this medicine.Other options include:Cream to reduce facial hairLaser hair removal or electrolysis to remove hairHormonal treatment to keep new hair from growingDoes PCOS change at menopause?Yes and no. PCOS affects many systems in the body. So, many symptoms may persist even though ovarian function and hormone levels change as a woman nears menopause. For instance, excessive hair growth continues, and male-pattern baldness or thinning hair gets worse after menopause. Also, the risks of complications (health problems) from PCOS, such as heart attack, stroke, and diabetes, increase as a woman gets older.Polycystic ovary syndrome and pregnancy- How does PCOS affect a woman while pregnant?Women with PCOS appear to have higher rates of:MiscarriagePremature deliveryPregnancy-induced high blood pressureGestational diabetesDoes PCOS put women at risk for other health problems?Women with PCOS have greater chances of developing several serious health conditions. Recent studies found that:Women with PCOS can have diabetes or pre-diabetes at early age.Women with PCOS are at greater risk of having high blood pressure.Women with PCOS can develop sleep apnea. This is when breathing stops for short periods of time during sleep.Women with PCOS may also develop anxiety and depression. It is important to talk to your doctor about treatment for these mental health conditions.Irregular menstrual periods and the lack of ovulation cause women to produce the hormone estrogen, but not the hormone progesterone. Progesterone causes the endometrium (lining of the womb) to shed each month as a menstrual period. Without progesterone, the endometrium becomes thick, which can cause heavy or irregular bleeding. Over time, this can lead to endometrial hyperplasia, when the lining grows too much, and cancer.I have PCOS. What can I do to prevent complications?If you have PCOS, get your symptoms under control at an earlier age to help reduce your chances of having complications like diabetes and heart disease. Talk to your doctor about treating all your symptoms, rather than focusing on just one aspect of your PCOS, such as problems getting pregnant. Also, talk to your doctor about getting tested for diabetes regularly. Other steps you can take to lower your chances of health problems include:Eating rightExercisingNot smokingHow can I cope with the emotional effects of PCOS?Having PCOS can be difficult. You may feel:Embarrassed by your appearanceWorried about being able to get pregnantDepressedManaging PCOS (Diet and Exercise)Following lifestyle and diet modifications can help manage PCOS symptoms to an extent-Frequently have small meals (5-6 times a day) without fail.Drink a lot of water (8-10 glasses)Try to consume 2-3 servings of fruits and vegetables every day.Stick to a high fibre diet (wholegrains/fruits/vegetables)Give preference to home cooked meals.Add brightly colored and white vegetables to your diet. They have high anti-oxidants.Food to avoid- Fried/packaged/processed foodsFoods with high glycemic indexExercises suggested- Work out at least 5 times every week for at least 30 minutesRunning, swimming, yogaStrengthening exercisesEven if you don't lose weight, exercise in PCOS helps to improve things like- insulin sensitivity, frequency of ovulation, cholesterol, body composition.Getting treatment for PCOS can help with these concerns and help boost your self-esteem. It is advised that you should consult gynecologist who can help you based on your symptoms and requirements to manage PCOD/PCOS.
Everything You Need to Know About Pcos (Polycystic Ovarian Syndrome)
Dr. Disha Sridhar, Gynecologist/Obstetrician
There are several issues becoming more prevalent with every passing day in today’s world. One such condition reaching near epidemic proportions is a dreaded and now very familiar name – PCOS. Here you will find everything you need to know about PCOS to get started.What is PCOS or PCOD?Polycystic ovary syndrome (sometimes referred to as disease depending on severity) is a problem in which a woman’s hormones are out of balance. It can cause problems with one’s periods and make it difficult to get pregnant. PCOS also may cause unwanted changes in the way you look. If it isn’t treated, over time it can lead to serious health problems, such as diabetes, heart disease and even cancers! Most women with PCOS grow many small cysts on their ovaries. That is why it is called polycystic ovary syndrome. The cysts themselves are not harmful, but lead to hormone imbalances. Did you know that symptoms of PCOS persist even when both the ovaries are removed? The root cause of the problem is not in your ovaries but in your metabolism.There is involvement of the hormone regulation centre at hypothalamus in the brain which affects multiple organs (Multi-system disease).Some of the symptoms are as follows: Acne.Weight gain and trouble losing weight.Extra hair on the face and body. Often women get thicker and darker facial hair and more hair on the chest, belly, and back.Thinning hair on the scalp.Irregular periods. Often women with PCOS have fewer than nine periods a year. Some women have no periods. Others have very heavy bleeding.Fertility problems. Many women who have PCOS have trouble getting pregnant (infertility).Depression.As if it was not bad enough, it increases your chances of developing a big disease later on in life, like full-blown diabetes, autoimmune thyroid disease and even cancers. The BioCycle study (NIH 2009) showed that untreated, hormonal imbalances increase significantly a woman's risk to diseases of inflammation - heart disease, diabetes, cancer, and premature ageing, not to mention a perpetual state of body suffering before these diseases even show up.The treatmentToday, the western medicine deals with identifying and treating the symptoms around PCOS. But these spot treatment are at best described as band-aid solutions to a much deeper problem that gets worse not only due to the ignorance of the root cause but also as side-effects of these symptomatic treatments over long periods of time. If you have been diagnosed with PCOS, chances are you have been prescribed Birth Control Pills or OC’s (oral contraceptives) for regularising hormone cycles and hence periods and metformin for elevated blood sugars or pre/diabetic conditions. All in an attempt to mask the symptoms but they come back in a worse form once synthetic hormones and pills are stopped. Lets have a look at these two so that you can get to the root of the problem and avoid potential side effects of these.Birth Control PillWhat it does: The synthetic hormones in the birth control mask your natural hormonal patterns to prevent ovulation from happening, and therefore prevent pregnancy. The menstrual period you experience on the pill is not an actual period, but rather a “break-through bleed” that occurs from the drop in estrogen. So even though it might be regulating your cycle, once you get off the pill chances are your period will return to the same state is was before and mostly it gets even worse.Side effects: Women who continually use contraceptive pills are more likely to develop circulatory problems (thrombosis and embolism), liver tumors, headaches, depression and cancer (especially breast cancer) than those who don’t use them. The risk increases with age. Metformin (Glucophage)What it does: Metformin helps with blood sugar and insulin management by suppressing glucose production by the liver. It’s commonly used for diabetes and PCOS with insulin resistance.Side effects: In a recent study, metformin was found to cause an impairment mental cognition. It’s more commonly known to cause serious digestive issues like gas, bloating, diarrhea, constipation, and more uncomfortable symptoms.If you are diagnosed with PCOS and you have been offered a prescription of birth control pills & synthetic hormones, PLEASE STOP!The advice to lose weight & exercise moreover, does not completely work either. They say that you should lose weight to be healthy but I say that you should be healthy to lose weight. I am sure you can relate to that. I am not here to criticize any system, and each kind of treatment has its own role.ConclusionVery often you'll be told that the only thing you can do is take a pill, but I hope this article has opened your eyes to the side effects of synthetic hormones and helped give you your power back when it comes to making informed decisions about treating your PCOS symptoms.There is no quick fix to treating PCOS. It is a systemic issues that needs to be managed through diet and lifestyle and holistic approach. If you’re ready to get to the bottom of your hormonal imbalances once and for all, let me help you. Your body CAN work for you. You can choose to stop suffering and start feeling good all month long.My thoughtsI believe it is my responsibility to share what I've learnt so that you and many others are not held back by PCOS & hormone imbalances, but rather use it as a way to improve your lives. I want to empower you. I want you to be the captain of your own ship because I know that if we take the necessary steps, we can improve not only our own lives, but those of our family, community & the world at large.‘The journey of a thousand miles begins with a single step’I will be glad to help you if you choose to take that first step in healing.Wishing you health & happiness!
PCOS Is More Than a Hormonal Disorder
Dr. Neelam Nath Bhatia, General Physician
PCOS-Poly Cystic Ovarian Syndrome or POCD-Polycystic Ovarian Disease means presence of tiny water filled balloons on the ovaries. Ovaries have developing follicles in women from puberty to menopause. A baby girl is borne with a numbers of them but they start maturing at puberty, few per cycle. Not every egg she is carrying gets ripe in each cycle & this is the way the capability of reproducing is protected in a woman.Few follicles develop & rupture per cycle, egg is released which travels towards uterus for implantation. Uterus has made arrangements to receive the mature egg for conception. In case no conception takes place, the lining is shed for 5 days in the form of periods.The size of follicles in Indian women is about 20 mm or 2 cms but some women may do have a size larger than this but it is never more than 2.5 cms.What is a Cyst? Cyst is a balloon with clear water like transparent substance.If Cysts are present in ovaries , it is a disease or a Lifestyle Disorder?Cyst in ovaries can be a big follicle that did not rupture on day 14- Ovulation time or it can be due to other reasons not known to us, but the affected woman gets diagnosed by an Ultrasound.She has symptoms of irregular periods, delayed cycles with less blood and obesity, acne on face, black patches here and there, hair loss, hirsutism (hair on face), risk of getting type 2 diabetes and heart disease, thyroid disease being on the low side and infertility / and if she conceives risk of a complicated pregnancy with high BP, swellings and pre eclamptic changes.Her blood levels are high for SteroidsTestosterone hormoneFollicle stimulating hormoneFasting blood sugar is high but herHDL-the good cholesterol is low CRP-C reactive protein is high-it is an indicator of inflammation and infection Anywhere in the body.Doctors usually prescribe a 21 day course of low hormone oral contraceptive pills, even to young girls who do not need it to prevent conception. Metformin medicine given to Type 2 Diabetics is also prescribed.But OCs / Hormone therapy does carry side effects like making periods more irregular than before, break through bleeding, weight gain, nausea, mood swings among others. PCOS can also be considered a lifestyle disorder:Correct it by modifying lifestyle byReduce the weight by taking no sugar, minimal salt, no bad fats like burgers, pizzas and street food, packed food rich in salt and fats as salt is a preservative and fats add to the taste.Do yoga and meditation Reduce stress but do enjoy the fruitful result oriented stress as it boosts the good cholesterol, Exercise regularly but according to constitution and tolerance.Eat as much as possible-every seasonalfruits and vegetables, at least 5 types with 5 different colours.Even borderline low thyroid becomes normal without giving extra thyroid hormones as tablets (eltroxin has lots of side effects like palpitations and high end personality who wants to be always on the go!)Take a glass of warm water with juice oflemon + a spoon of honey added to it, every day in the morning on emptystomach. This helps to reduce weight, bring down levels of blood sugar andcholesterol.Apple cider vinegar if taken with juice/water /honey helps also.Treat PCOD minus hormones & sugar lowering medicine metformin
Missed Periods-Is It Because of PCOS or Unwanted Pregnancy
Dr. Himani Gupta, Gynecologist/Obstetrician
For most women , getting her menses (period ) on time in regularity and flow is a very important matter. This holds true regardless of marital status. Whether she is married or unmarried, she does not want to miss her chums.Many times the management of missed periods rely on correct diagnosis.Two most important reasons for delay in getting periods are PCOS (Polycystic Ovarian Syndrome-A hormonal imbalance disorder) and Unwanted pregnancyDifferentiating correctly between theses two will make timely treatment available in both the cases.Problem of irregular menses and PCOS is rampant these days. Changing lifestyle, dietary patterns are environmental factors responsible for it.Education and career demands on women will make them move out of their family domain and stay on their own managing everything about themselves. This will add further to their stress levels. Relationship status in new social paradigm is ever changing.Knowingly or unknowingly this is another stress factor.It becomes imperative to them that periods (menses) come on time.If they put missed periods on PCOS, at times their self-diagnosis is incorrect.On the face of unprotected sex and having taken an emergency contraceptive pill ( Over The Counter emergency unwanted pregnancy protection tablet) sometimes they find themselves facing an unwanted pregnancy.Away from home and family and at times short of money too, they may look for quick fixes with local doc/ family doctors instead of qualified Gynaecologist. This will further complicate the clinical pictureThe first step towards resolving the issue is to seek the consultation of an expert Gynaecologist in your area. For those who are in a relationship , a pregnancy test should be done. Depending on the test results the treatment is offered.If the pregnancy test is positive, and the woman wants to discontinue, it is best to do so at the earliest as newer methods of abortion like abortion tablets work well in those pregnancies which are of shorter duration. In early cases, the complications rate is also less.If a pregnancy test is negative, hormonal tests and sonography are advised to arrive at a correct diagnosis.In either case scenario, your Gynaecologist will help you in getting the correct treatment.
PCOS Has Become as Common as Common Cold These Days
Dr. Geetanjali, Dietitian/Nutritionist
Polycystic Ovary Syndrome (PCOS) has become as common as common cold these days. It affects at least one in every ten women ageing towards puberty. PCOS is an aftermath of a hormonal imbalance in women wherein the testosterone levels shoots up in the body causing an array of symptomatic reactions.A woman with PCOS is prone to weight gain, pelvic pain, acne, depression and irregular menstrual cycles. But that’s only as far as the horror factors go. Firstly, like I have mentioned before, PCOS has become indescribably common among women of a certain age these days. Secondly, with a treatment, proper diet and exercise schedule, PCOS is quite curable.Here are a few tips and tricks for you to keep in mind and compile them with your treatment to stay several steps ahead of PCOS.PCOS and Weight gain Between PCOS and body weight, it’s a long, enticing affair that takes place. PCOS makes it difficult for the body to use insulin; a hormone that is responsible for converting food starch into energy. As a result, your body becomes insulin resistant, and stores up the energy as fat instead of burning it out. High insulin levels make it a troublesome affair to maintain a manageable weight.Diet tips that work wonders with PCOS Carbohydrates are one of those food components that really make your insulin levels tick. But not all carbs are the bad guys. It’s the simple carbs that you need to watch out for. Even if you gulp down foods with the same amount of carbohydrate, the effect they will have on your insulin level will vary depending on the type of carb that you have consumed. So, it helps to stay wide awake every time you go grocery shopping. Make a few necessary tweaks to your grocery list and consumption pattern, and before you know your PCOS will be an ancient thing in the past. Next time you go to the departmental store, make sure you pick whole grains over multi-grains. You could switch from cornflakes to wheat flakes or oatmeal as far as breakfast is concerned. Here’s another small fix you can pull. Swap your white bread with its brown counterpart and do the same with your rice. It’s always more advisable (and beneficial) to eat whole fruits instead of drinking canned juices. And, most importantly let not those ‘fat-free’ levels laugh it off at you; they are secretly loaded with a truck full of sugar.To further fine tune your PCOS diet; build up on smart snacking habits. Open a packet of unsalted peanuts rather than salted potato chips. Having a tantrum with the sweet tooth? Smoothen it out with tidbits of dark chocolate. Rely on water (and water alone) to quench your thirst. Choose this essential and harmless liquid to curb down your soda and soft drink pangs entirely. Eating a little consciously can take you a long way to get rid of PCOS. Top up your dietary efforts with your regular exercise alongside your treatment, and there’s no reason why your hormones won’t fall into place along with your life
Weight Gain & Polycystic Ovarian Syndrome (Pcos)
Ms. Swati Kapoor, Dietitian/Nutritionist
Women with PCOS due to the increase in weight and general insulin resistance in the body are more prone to diseases like diabetes and heart. All these conditions can be avoided by simply following a exercise and healthy eating routine specific to this medical condition. The most common mistake made by people with this condition is that they go on fad diets or start starving themselves. All this will do nothing to the condition but only make it worse, making you more susceptible to additional nutrition deficiencies like osteoporosis etc. Here are three simple steps to lose weight with PCOS:Step 1- Eat Right:- Limit Carbohydrate Intake: Limit the intake of carbohydrate to 40-50 percent of the total diet per day.- Avoid Refined Carbohydrates: refined carbohydrates like Maida-based or sugar, shoots up insulin levels which worsen the symptoms associated with PCOS and promote abdominal fat storage.- Include Low Glycemic Index (GI) foods: Foods with a low GI release sugar into the blood more slowly, resulting in a slow and steady release of insulin preventing insulin resistance. Low GI foods include those high in fiber, fresh vegetables and some fruits and protein-rich.- Incorporate Soya: Soya and its products have phytoestrogen properties which mimic female hormone –estrogen bringing about beneficial effects.- Eat at Regular Intervals: Any variation in meal timings puts pressure on the glands to release more of contra-PCOS hormones.- Salt Restriction: Is another major aspect to prevent water retention and to relieve the symptom of bloating.Step 2- Exercise:Regular exercise helps controls insulin levels and reduces depression. The best forms of exercises for women with PCOS are:- Cardiovascular Exercise- Interval Training- Strength TrainingStep 3- Sleep:Regular and adequate sleep pattern has an effect on blood glucose management. One study showed that otherwise normal people who were deprived of just one night's sleep had impaired glucose/insulin systems. A good night sleep of 7-8 hrs/day is therefore essential to mitigate symptoms of PCOS arising out of insulin resistance. Lifestyle modifications including stress reduction, exercise, and balanced diet have positive effects for PCOS women planning to conceive.
Getting Pregnant With Polycystic Ovaries (Pcos)
Mr. Preshanthan M S
“From embarrassing visible signs like chin hair and acne, to more worrying ones like missed or irregular periods, polycystic ovary syndrome can affect your health, leading to diabetes, infertility and even cancer. Dr.Samundi Sankari, Chief Consultant - Srushti Fertility Centre Chennai tells you how to spot the symptoms of this sometimes silent disease”SYMPTOMSPCOS is untreatable, but can be managed. Irregular menstrual cycles and difficulty conceiving are among the most common symptoms, the result of ovarian follicles that fail to mature fully and to release eggs. Affected women often have enlarged ovaries and prolonged bleeding during menses. The hormone imbalances is characterised by the distinctive symptoms such as irregular periods, Excess facial hair and thinning and falling of hair, weight gain, oily and acne prone skin, pigmentation - around neck, armpit or thighs, Infertility and Insulin resistance-diabetes. The healthiest, most effective long-term method of managing PCOS is to live a healthy lifestyle: proper diet, accompanied by regular exercise, regularizing healthy sleep pattern and effectively managing stress could help normalize the body metabolism and reduce potential risks of PCOS such as Infertility and Diabetes.“LOSING WEIGHT REDUCES YOUR INSULIN LEVELS, RESULTING IN LOWER TESTOSTERONE LEVELS, WHICH IN TURN IMPROVES FERTILITY AND REDUCES VISIBLE SYMPTOMS SUCH AS EXCESSIVE HAIR GROWTH AND ACNE”PCOS AND INFERTILITYPCOS has a direct impact on your fertility and ability to conceive. In recent years, there has been increase in incidence where woman who underwent infertility treatment at Srushti were diagnosed with PCOS, but most of them had their other fertility factors as normal. About 30% of women who took treatment where able to conceive naturally with just lifestyle modifications. Half of the women with irregular periods conceived with ovulation induction, follicular monitoring and timed sexual intercourse or Intra Uterine Insemination (IUI). Women who had severe PCOS were treated with laparoscopic ovarian drilling and most of them were able to conceive naturally post treatment and others conceived through Assisted Reproductive Techniques such as In Vitro Fertilization (IVF).Dr Samundi Sankari says many women won’t have any symptoms while having PCOS. Huge number of PCOS patients, particularly women in their early or late 20’s who come to me only when they have fertility issues. We advise women in the reproductive age group to visit their gynaecologist at least once a year, regardless of whether they have any symptoms or complaints.
Managing Polycystic Ovarian Syndrome ( Pcos)
Dr. Smita Vats, Gynecologist/Obstetrician
Polycystic Ovarian Syndrome, also known as Stein Leventhal Syndrome, is a complex , metabolic disorder characterised by:Menstrual abnormalities, an ovulationAndrogen excess ( Excess of Male hormones)Ultrasound findings of Polycystic ovariesSubfertility/InfertilityA number of hormonal imbalances & interactions lead to Insulin resistance in many of these patients. The longterm risks are of developing Diabetes, Heart disease, Hypertension, Endometrial cancer etc in later years.The treatment of PCOS is primarily by Lifestyle modification which includes:Diet control - Avoid fatty, oily foods eg Chips, Burgers, French fries, chocolates, cakes, fried snacks etc. Eat more of home cooked, healthy food, containing at least 2 fruits per day, 3-4 vegetables/day.Exercise at least 30-45 minutes everyday - Be it Jogging, brisk walking, dance, sports, skipping, aerobics or any other activity of your choice. It should be a moderate, sweat inducing exercise.Weight loss - Losing even 5% of your weight can go a long way in resolving your symptomsIf needed, you maybe advised Combined hormonal pills or insulin sensitising medications to treat the hormonal imbalance for a short while ( 3-6 months) but by & large, it should be your lifestyle modification which takes over for complete correction of the situation.Hair & acne can be managed by medications & cosmetic therapies and fertility enhancing medications maybe needed to treat infertility & promote ovulation ( Egg production)You should consult a specialist to get a complete evaluation of your condition done in a methodical manner & chalk out a treatment plan in consultation with the experts. |
I had paused to watch as a number of primary school aged students were rallying to begin a soccer game. Some of the players wore T-shirts which were green and the others wore plum colored T-shirts and those colors seemed to identify the teams. A number of observers who were also in the 10 to 12-year-old range gathered to observe the competition. Many of these observers also wore plum or green colored shirts. One of the plum shirted observers had a cinnamon colored Pomeranian dog with her. As she moved around the edge of the field she encountered another girl wearing green. I don't know what the situation was but the girl with the dog made what appeared to be a series of angry comments pointing at the other girl who stoically held her ground and did not seem to respond in turn. As the plum shirted girl with the dog began to move away the dog made a wide circle to avoid the green clad girl who had been the target of her mistress's anger. Then somebody from behind them called and the girl with the dog reversed her course and once more passed by girl wearing green. Again the dog swung widely away to avoid drawing near the girl in green. At that moment the part of my brain which deals with behavioral observation and analysis clicked in. It seemed to me almost as if the negative emotional outburst of the dog's mistress had been clearly interpreted by the dog as belonging to the girl in green. The dog was now avoiding that person who was the target of her owner's negative feelings.
In human infants the ability to recognize emotions and to understand that they may be associated with a particular object has been verified in toddlers aged 14 to 18 months. I remembered a paper published in the journal Developmental Psychology a few years back. It described a study by psychologist Betty Repacholi, who was then working at the University of California at Berkeley. She arranged a room with two boxes, and had the child's parent look in each box. When looking in one box the parent expressed a very positive and happy emotion, however while looking in the other box the parent expressed disgust. When the child was later allowed to explore the room the vast majority of the children went to the box which had been attached to the happy expression and avoided the box which was associated with the emotion of disgust.
This same general research method was recently adopted by Isabella Merola, Emanuela Prato-Previde, M. Lazzaroni, and Sarah Marshall-Pescini at the University of Milan and the results were published in the journal Animal Cognition. They added a few twists so they could not only see whether dogs recognized a human's emotional expression and might attach it to particular objects, but also to see whether the expressions of the dog's owner were more likely to be recognized and acted on than those of the stranger. There were a number of different conditions and analyses but let's stick to the ones which are most important for this discussion.
dog canine pet emotion communication anger feeling sentiment
The setup involved two boxes each containing a toy. In the main experiment 55 dogs were tested and in one condition the dog's owner looked into one box and simulated a happy expression sounding very enthusiastic and interested and saying (in Italian) things like "oh nice, really nice" using tones that were high pitched, musical and positive. While looking at the other box the owners were told to sound as if their dog were about to do something dangerous or they had witnessed something shocking and fear provoking. This resulted in something like an exclamation of "Oh! How ugly!" spoken in as tense a tone of voice as the dog owners could manage. In addition, the owner was also told to act out the emotions using body language, such as crouching more toward the box when the positive emotional expression was being made and jumping back from the box when expressing the negative emotion. Afterwards the dogs were released and allowed to explore the room. 81% of the dogs went to the box associated with the happy expression, which shows that the dogs not only recognize their owner's emotional expressions but attach those emotions to whatever object their owner was looking at or addressing at the time. When the same emotions were expressed by a stranger, the dogs did not seem to give them enough credence to guide their behaviors and the dogs performed virtually at chance levels with only 46% going to the box where happiness was expressed.
In a subsequent experiment it was found that the dogs are more likely to act on positive emotional expressions than on negative. In this experiment involving 40 dogs, the same procedure was repeated except that for one box the owner expressed a positive, happy emotion, while for the other box the owners were asked to use a neutral expression, as monotone and free of emotion as they could, saying something like "Oh that's useless". In another group the negative, fearful, emotion was paired with this neutral expression. In the case of the positive emotion and 75% of the dogs chose the "happy" box. The dogs acted at chance for the pairing of the neutral and the negative emotion, suggesting that dogs are looking for the good things in life rather than necessarily avoiding the bad things. Once again having the emotions expressed by a stranger did not influence the dog's behavior at all.
So once more we find that dogs act like young children. Your dog is watching you, and learning what you like and approve of, and guiding his behavior based upon your emotional responses.
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What are some good unisex gifts for people under 20?
Quick Answer
Board games, books, electronics and movies are some unisex gift ideas for people under age 20. Handmade items can also be a hit, especially if they are fun, funny, funky or functional.
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What are some good unisex gifts for people under 20?
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Full Answer
For young children, some of the best selling games on Amazon.com in 2015 are "Sorry!," "Pie Face!", the "Despicable Me" version of "Memory," "Hungry Hungry Hippos" and "Candyland." These games require minimal literacy skills and tend to last less than 15 minutes. For older kids, teens and young adults, the most popular games are "Ticket to Ride," "Pandemic," "Catan" and "Betrayal at House on the Hill." With a more complex storyline and a greater reliance on strategy, these games tend to appeal to boys and girls equally.
The most popular young adult books on Goodreads.com include "Winter" by Marissa Meyer, "The Boy Most Likely To" by Huntley Fitzpatrick and "An Ember in the Ashes" by Sabaa Tahir. "Where the Wild Things Are," "The Very Hungry Caterpillar" and "The Giving Tree" are popular children's books.
Fitbit activity wristbands, which track steps taken throughout the day, distance traveled, calories burned, stairs climbed and minutes spent being active, are an electronic device favored among people under 20. The popular iPad Mini allows users to download music, books and video, use Skype and surf the Internet. Noise cancelling ear phones are well-liked, as are laptop BookBooks, which are Neoprene-padded sleeves for laptops.
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What are some ways to combat a pigeon problem on a balcony?
Quick Answer
A homeowner can reduce a pigeon infestation on a balcony by installing low-voltage electric wires, using ultrasonic devices, applying non-toxic sprays, scaring the birds and using traps. To prevent pigeons from congregating, avoid storing food or garbage near the balcony, install anti-roosting spikes or strings to make roosting uncomfortable, and sprinkle pepper or cinnamon in the vicinity.
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Full Answer
Pigeon droppings are unattractive, can damage the finish on buildings, and contain dangerous fungi and bacteria harmful to humans. Pigeons may carry diseases including encephalitis and salmonella and can transport, fleas, ticks and mites.
Homeowners may want to consider measures that completely prevent pigeons from congregating, such as adding screens and netting to the balcony and creating sloping surfaces where pigeons are likely to roost such as railing, awnings and over light fixtures. The homeowner should ensure that neither she nor her neighbors ever feed the birds.
To scare off pigeons, spray them with a water hose, use reflective tape or Mylar balloons, make loud noises with exploding party favors, or install a statue of an owl or other predator.
An ultrasonic device uses a combination of wave forms to create noise that interferes with the method birds use to talk to one another. The device does not scare the birds, but discourages them from flying into or spending time in the area.
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What are some mind control techniques?
Quick Answer
Mind control techniques require isolation of the subject and complete dependence on an authority, and the first phase of thought reform breaks down the subjects' egos. The authority figure imposes a new identity through behavioral modification, coercion and repetition. Finally, the authority offers the subject the illusion of choice, which is followed by rebirth and overwhelming relief. As of 2014, very little evidence exists to support the veracity of brainwashing.
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What are some mind control techniques?
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Mind control refers to theoretical processes utilizing any tactic, psychological or biochemical that inhibits a person's autonomy and involuntarily alters her values and beliefs. To achieve this, the authority repeatedly assaults the subjects with claims that they are not who they think they are, and they do not know what they think they know. This continues until subjects become so confused or disoriented that they agree. The authority then shames the subjects until they deny all previous attachments and values. The feelings of betrayal to loved ones and former principles demoralizes the subjects even more.
Subjects are then instructed on the correct course of action while the authority plays mind games designed to reinforce new values and behaviors. These include mind-numbing exercises, such as monotonous chanting, rhythmic praying and repeating decrees. Subjects are required to confess in order to continue the sense of dependency. They are forced to use a new name. The authority rewards behaviors that conform to the new values and punishes those that don't. Sometimes psychoactive drugs are used to enhance suggestibility.
The subjects are told that their former beliefs are bad, not the subjects themselves. This leads to the illusion that the subjects came to their own conclusions. The authority offers a peaceful new life. Subjects are then placed in environments free from any contradictory influences where they can live according to these new beliefs without questioning them.
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Author: Sydney Bauer
This lesson introduces the concept of plots in fiction.
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What it is (and what it isn’t)
One of the most classic examples of what is and is not considered “plot” in a work of fiction is the following excerpt (paraphrased) from E.M. Forester’s Aspects of the Novel (1927):
To say that the King died and then Queen died is to tell a story (a simple synopsis of events, presented chronologically).
To say that the King died and then the Queen died of grief is to build a plot (a link is formed between the two events, making connections, developing a pattern).
Think of story and narrative as the raw material that plot is made out of: a simple chronological telling of events. Plot is the selective arrangement of narrative events to create cause and effect relationships between each event, which is again the difference between the two sentences in the above example. Narrative is considered to be what is told, whereas plot is considered to be how the material is organized and presented to the reader so that the text will have a specific effect on him or her.
Plot forms a chain of interrelated events. It determines which elements and events of the story are presented to the reader, as well as the order in which they appear. Plot focuses the reader’s attention and depends on him or her to draw inferences between actions and events. It is the structure or pattern that controls the other elements of the narrative.
Plot includes the initial moment of calm and balance (equilibrium), the rising action, complications, the climax, the falling action, the denouement, and the end. This general pattern creates the arch of the storyline.
Plots can be
• linear (does not reorder events, presents them chronologically)
• nonlinear (drastically reorders events)
• episodic (is a chain of individual events, rather than events that are a part of a whole).
Franz Kafka’s “Metamorphosis”
Plot: Rather than tell the entire life story of Gregor Samsa, Kafka selects to tell the events that take place after Gregor mysteriously transforms into a large beetle. Even within that small window of time, Kafka is very selective as to which scenes are described. Again, he does not tell the reader everything that happened to Gregor while he was a beetle, only what he believes will create interest and tension.
Harper Lee’s To Kill A Mockingbird
Plot: The coming-of-age story of Scout and Jem Finch. The story, told from Scout’s perspective decades later, follows the two Finch children as they spy on their spooky neighbor, get into scuffles with other kids in town, and eavesdrop at the court house during a rape trial. The text spans several years, focusing mainly on a few summers, which is when most of the events take place. Again, the narrator and the author select which details to tell the reader. |
Research Project: How Brake Fluid Works
Price: $15 USD
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For this assignment you will do some research on how brake fluid works. Brake fluid is a liquid used as part of a fluid power system. You can research how brake fluid works online using a keyword search such as “how brake fluid works.” Here are two sites that can get you started (one of these has audio, please adjust your volume level to a reasonable level):
Create an informational brochure or a multimedia presentation (such as a slideshow) to explain why it is important to check your brake fluid regularly. Your brochure or presentation can be creative, but be sure to explain what happens to the fluid when you step on the brake of a car and how that fluid then acts to make the car slow down. You must also tie your understanding of braking into the concepts you’ve studied about in this section. Then explain why it is important to make sure that your car always has an adequate supply of brake fluid.
Submit your completed brochure or presentation to the Research Project: How Brake Fluid Worksassignment link for grading.
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Celebrations as Hull House Museum reopens
September 8, 2010 2:51:10 PM PDT
Nobel Peace Prize winner Jane Addams was called the 'Mother of Social Work,' and Wednesday, the Jane Addams Hull House Museum reopened officially with a huge block party.The event, which was being called the "People's Block Party' was just getting under way Wednesday evening. It marks the grand opening of a building that was once Jane Addams' home and is now a tribute to her pioneering social work.
The celebration falls on the 150th anniversary of Addams' birth. Her work on behalf of the underprivileged at the turn of the 20th century earned her the title "Mother of Social Work."
"She was a woman who was about leadership to the city at a time when the city needed help," said Clarence Wood, CEO, Hull House Association.
Wood and others work to carry on Addams' vision by providing a spectrum of services to those in need. Supporters gathered at Daley Plaza to honor a person they call an advocate for human rights. They say much of the causes Jane Addams fought for are still important today.
Addams earned the Nobel Peace Prize in 1931, becoming the first American woman to receive that honor. It's on permanent display at her home.
"There was a time when 800 S. Halsted was the most important address in the world," said Cindy Sargent, a Hull House board member.
The museum reopened Wednesday following renovations. Visitors can see, among other things, exhibits of the original settlements, a complex of buildings where people could live, work and enrich their lives. It was set up by Addams as a way to create conditions for peace.
"That meant fighting for public housing, for public health, for working, for immigrants' rights, for women's rights, to really fight for fair labor practices," said Lisa Lee of the Hull House Museum
The renovation costs $800,000. Hull House and another building are two of the buildings left of the original 13 buildings that made up the settlement. The other buildings were torn down to make way for UIC's campus.
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How Poaching Works
Poaching Laws
In the 1500s, killing deer meant death to anyone but royalty [source: nationmaster]. Between the mid- 1700s and the first half of the 1800s poachers were hanged or sent to Australia, especially if guns were used or a gamekeeper was injured in the crime [source: Scribd].
It used to be that poachers were able to keep their licenses as long as they paid their fines, and in most states, jail time was unheard of. Today, as poaching problems grow and more species are becoming threatened or endangered, laws are getting tougher and citizens are getting angrier. Law-abiding hunters view poachers as villains who ruin the good name of legal hunting.
Currently, poaching laws vary by state. In Pennsylvania, while poaching is considered a summary offense with no chance of imprisonment, lawmakers are actively pursuing stiffer penalties and fines. West Virginia has lower fines but imposes stiff jail terms for poaching offenses. A third offense gets you a felony conviction, with up to a $10,000 fine, one to five years in prison and a lifetime hunting license revocation [source: Pennsylvania Game Commission].
Ohio toughened its laws recently to include restitution values based on true-market value, fines and revocation of hunting licenses not only in Ohio but also in neighboring states [source: BuckeyeFirearms]. In Minnesota, the Department of Natural Resources cannot only confiscate a poacher's hunting and fishing licenses but also his boat and gear as soon as the value of whatever was poached hits $500 [source: Great lakes Directory].
Canada is battling its own poaching wars, but you might be surprised to learn that it's for fish. Using large drift nets, poachers target salmon, sturgeon, rockfish and shellfish. Canada does not only punish the poacher but also whoever purchased the poached fish.
The effects of poaching probably have a wider range than you might think. Forge ahead to check out the consequences of poaching.
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Math Camps
One summer option that has traditionally been popular among math majors is to work at a math camp for high school students. Typically, undergraduates serve as counselors, helping students with problem sets, providing general supervision, and serving as older friends and mentors to the students. Many find the job to be both fun and rewarding, and some Princeton students have chosen to spend most of their summers at camps like this. The most popular by far among Princeton students are the Ross Mathematics Program, held at Ohio State University, and PROMYS, held at Boston University.
Ross Mathematics Program
The Ross Mathematics Program, pretty much universally called just “Ross,” is an intensive six-week course in number theory for high school students. Over the course of the program, the students work through a huge chunk of fundamental number theory, starting with an axiomatic construction of the integers and culminating with a proof of Gauss’s quadratic reciprocity theorem. The emphasis is on solving problems—there’s a problem set every day and the problems guide the students step-by-step through proofs of many tricky results, including quadratic reciprocity—and learning to think mathematically, which is to say, both intuitively and rigorously. Counselors live in the dorms with the students and take charge of a small “family” (four to five students) and sometimes a junior counselor, an advanced returning student who is ostensibly in training for the role of counselor. If you work here, you’ll be expected to grade your students’ problem sets quickly and provide useful feedback that will allow them to progress as far and as rapidly as they can. All in all, it’s a rewarding job that leaves plenty of time for personal interests, and the Ross community is wonderful.
PROMYS is the child of the Ross program and is similar in many ways. The program parallels that of Ross, starting with an axiomatic construction of the integers and ending with a proof of Gauss’s quadratic reciprocity theorem. Again, the emphasis is on problem solving and thinking mathematically, and a problem set is assigned daily. Student “families” consist of 4-5 students, usually with one advanced returning student, who take advanced courses like Algebra, Galois Theory, Geometry and Symmetry, Combinatorics, and Modular Forms. Counselors’ roles includes grading family members’ problem sets quickly, guiding students through the program, and marking for an advanced course. There is spare time, however, and fun activities for both participants and counselors. It’s a rewarding job that, like Ross, has traditionally been popular with Princeton undergraduates.
Canada/USA MathCamp
Canada/USA MathCamp is another major math summer program for high school students. Undergraduates are hired to work as junior counselors (JC’s), a job which is much like that of counselor at Ross or PROMYS. Unlike these other programs, however, Canada/USA MathCamp only hires alumni.
Contacts: Max Rabinovich ’13 (; Erick Knight ’12 ( |
Can I Give My Cat Lentils?
Can I give my cat lentils?Animals will eat anything they like, even lentils if they have the chance. You can’t force them to want something, but when they do, there is no stopping them. This can only be stopped if you get in the way and prevent them from doing so.
In the case of cats and eating lentils, some of them do like to eat the vegetable. For a lot of them, they really go bonkers over the stuff. Cats are referred to as obligate carnivores which means they need meat to survive. However, there are plenty of nutrients from vegetables that can be beneficial for them.
Can I Give My Cat Lentils? Answer: Yes
The simple answer is yes. Lentils are not poisonous or hazardous for felines but it is quite unusual since we all know that cats survive on either meat or the cat food that we feed them. It is unusual, but not unheard of among cat lovers. In fact, a lot of owners try to mix in greens with their cat’s diet in order to get various sources of proteins and nutrients, and lentils are one of them.
One of the questions is: will my cat eat lentils? Surprisingly, yes. You never can tell what a specific cat would eat or not eat. Some would prefer meat and cat food alone, while a select number will chomp on lentils as well as other greens. What you should never do is force your cat into a vegan diet. A feline’s digestive system does not work the same way as ours do. Cats still need protein in order to survive. Lentils are just a good addition to their diet in which they could get carbohydrates as well as some other nutrients. On the other hand, if you believe your cat can survive on lentils and vegetables alone, consult a veterinarian first.
The Benefits for Cats
Like most vegetables, there are many benefits of feeding your cat some lentils every once in a while. For one, they have a high concentration of protein. As a matter of fact, lentils contain the most protein among all the vegetable food known to man. So, if you wish to feed your cat a lot of protein other than meat as a protein source, lentils are a great substitute. Take note of the word “substitute” and not use the food as a replacement for the cat’s need of meat.
B Vitamins are also found in lentils. So if you wish to increase the amount of these vitamins that your cat eats, feed it lentils and you’ve got a great source of B vitamins right there. Notably, lentils contain Vitamin B3 and folate. Another benefit of lentils for cats is that they are loaded with iron. Of course, iron can be found in meat products but lentils are a great substitute as a source for the nutrient.
How to Prepare Them
There are many ways in which lentils can be prepared for cats. Most cat lovers will tell you their own version on how they prepare the vegetable for their pets. However, there are accepted procedures in which lentils should be fed to felines. Some would prefer to feed them raw, but this would cause indigestion for most cats. Remember, their digestive system is way more sensitive than humans so you need to be careful on how you feed them the vegetable.
The best way to prepare lentils is to cook them by boiling them slowly until they become soft. This way, your cat won’t have a hard time eating them and will be digested properly. Otherwise, they might end up with loose bowel movement as well as indigestion, which is something you do not want to happen to your cat.
A Word of Caution
Never force your cat to eat anything it does not like. You may think you are doing it a favor, but you’re actually making it worse. If you try to feed it lentils and your cat likes them, that’s well and good. However, if he it repulsed by the idea, don’t force your cat into it. Otherwise, train your feline buddy to eat lentils as a kitten so it will get used to it as part of its normal diet.
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May 22 events in history
853 A Byzantine fleet sacks and destroys undefended Damietta in Egypt
1176 The Hashshashin (Assassins) attempt to murder Saladin near Aleppo
1200 King John of England and King Philip II of France sign the Treaty of Le Goulet
1246 Henry Raspe is elected anti-king of the Kingdom of Germany, in opposition to Conrad IV
1254 Serbian King Stephen Uroš I and the Republic of Venice sign a peace treaty
1377 Pope Gregory XI issues five papal bulls to denounce the doctrines of English theologian John Wycliffe
1455 Start of the Wars of the Roses: at the First Battle of St Albans, Richard, Duke of York, defeats and captures King Henry VI of England
1629 Holy Roman Emperor Ferdinand II and Danish King Christian IV sign the Treaty of Lübeck to end the Danish intervention in the Thirty Years' War
1762 Sweden and Prussia sign the Treaty of Hamburg
1807 Most of the English town of Chudleigh is destroyed by fire
1809 On the second and last day of the Battle of Aspern-Essling (near Vienna, Austria), Napoleon I is repelled by an enemy army for the first time
1812 Action of 22 May 1812: A small French two-frigate squadron comprising Ariane and Andromaque, returning from a commerce raiding campaign in the Atlantic, meets the 74-gun HMS Northumberland while trying the slip to Lorient through the British blockade
1816 A mob in Littleport, Cambridgeshire, England, riots over high unemployment and rising grain costs; the rioting spreads to Ely the next day
1826 HMS Beagle departs on its first voyage
1840 The transportation of British convicts to the New South Wales colony is abolished
1848 Slavery is abolished in Martinique
1849 Future U.S. President Abraham Lincoln is issued a patent for an invention to lift boats over obstacles in a river, making him the only U.S. President to ever hold a patent
1864 American Civil War: After ten weeks, the Union Army's Red River Campaign ends with the Union unable to achieve any of its objectives
1871 The U.S. Army issues an order for abandonment of Fort Kearny in Nebraska
1872 Reconstruction: U.S. President Ulysses S. Grant signs the Amnesty Act into law restoring full civil and political rights to all but about 500 Confederate sympathizers
1897 The Blackwall Tunnel under the River Thames is officially opened
1903 Launch of the White Star Liner, SS Ionic
1915 Lassen Peak erupts with a powerful force, and is the only mountain other than Mount St. Helens to erupt in the contiguous US during the 20th century
1915 Three trains collide in the Quintinshill rail disaster near Gretna Green, Scotland, killing 227 people and injuring 246; the accident is found to be the result of non-standard operating practices during a shift change at a busy junction
1926 Chiang Kai-shek replaces communists in Kuomintang, China
1939 World War II: Germany and Italy sign the Pact of Steel
1942 Mexico enters World War II on the side of the Allies
1943 Joseph Stalin disbands Comintern
1945 Operation Paperclip – United States Army Major Robert B. Staver recommends that the U.S. evacuate German scientists and engineers to help in the development of rocket technology
1947 Cold War: in an effort to fight the spread of Communism, the U.S. President Harry S. Truman signs an act into law that will later be called the Truman Doctrine. The act grants $400 million in military and economic aid to Turkey and Greece, each battling an internal Communist movement
1961 An earthquake rocks New South Wales
1962 Continental Airlines Flight 11 crashes after bombs explode on board
1963 An assassination attempt of Greek left-wing politician Grigoris Lambrakis, who will die five days later
1967 Vietnam War: Vinh Xuan massacre
1969 Apollo 10 's lunar module flies within 8.4 nautical miles (16 km) of the moon's surface
1980 Namco releases the highly influential arcade game Pac-Man |
Alexei Sergeev: Dialogue With an Adventist Art Historian in Russia
Alexei Sergeev is an administrator at the renowned Hermitage Museum in St. Petersburg, Russia. Born in 1947, he is a trained art historian and a linguist, fluent in English, French, German, and Italian. After completing his secondary education, Sergeev studied at the Institute of Culture and later at Zdanov University in Leningrad, where he obtained a teaching degree in French language, literature, and culture.
In 1971, while still a student at the university, Sergeev began working at the Hermitage Museum. After graduation, he was promoted to be administrator of the educational department and since then has served as administrator of several other departments.
Sergeev recently completed his first lecture tour of Adventist colleges and universities in the United States, sponsored by a La Sierra University art foundation. We interviewed him during his visit to Washington, D.C.
Please tell us about your family background.
I was born in Leningrad, which in 1991 reverted to its original name—St. Petersburg. My father was the head of the main bank in the city. When I was three, a car ran over my father and killed him. My mother was just told the news. Even today we do not know the details. Both my parents were Russian Orthodox Christians, and my mother took me to church every Sunday.
St. Petersburg is quite a famous city.
It is. In fact it's a classical city, with beautiful palaces, churches, and public buildings. Pounded by Peter the Great in 1703 on the northwestern comer of Russia, the city served as the capital of the Russian Empire for two centuries and has continued to play a vital role in our nation's history. During World War II it suffered a terrible siege and was fiercely defended. The city has always been a cultural center, open to the rest of Europe, attracting writers, artists, and creative people. I'm proud to be a citizen of St. Petersburg.
What makes the Hermitage a special museum?
The Hermitage is one of the largest museums in the world. It includes more than 350 exhibition halls in five large interconnected buildings. The art collection was started in 1764 when Catherine II purchased 225 paintings in Berlin. Through the centuries, it has continued to grow, not only with many additional paintings, but also with hundreds of engravings, drawings, carvings, coin collections, and books, including Voltaire's personal library. Each year 3.5 million people from all over the world visit the museum.
What are some of the unique art works exhibited at the Hermitage?
The museum has a Rembrandt collection of 24 paintings that represent the main periods of his life. Among them is the famous "Return of the Prodigal Son." There are also two beautiful paintings by Raphael and two by Leonardo da Vinci. The list could go on and on.
When did you become interested in art?
As a child, going to the Orthodox church with my mother, I was attracted by the icons—those beautiful paintings of religious people and scenes that decorate the walls and ceilings of the Christian churches in the Eastern tradition. My mother also showed me art books with illustrations. Later I began to visit the Hermitage and admire the paintings of the western European artists and the Russian masters.
What are your responsibilities at the museum ?
I have worked in several departments, conducting research and training the staff. Frequently, because of my ability to speak several languages, I'm asked to guide some of the special visitors who come to the Hermitage. They represent many countries and professions such as government officials, dignitaries, religious leaders, writers, and artists. Some of them visit the museum privately, and we have very interesting conversations.
What gives you satisfaction in your work?
I enjoy showing visitors the master-pieces and paintings from various periods and styles. I get a lot of satisfaction when I notice that a visitor captures the meaning of a particular work of art and enjoys the experience.
Are you interested in a specific period in the history of art?
I have studied in depth French art of the 18th century, the period before the French Revolution. During the late Baroque and the Enlightenment, there was an attempt to make the world a better place by sheer human effort, without any spiritual or divine dimension. There was the illusion that national-ism could subdue the problem of evil, only to explode tragically during the French Revolution and the Napoleonic Wars.
Do you find modern parallels to that period?
We repeated the experiment in the Soviet Union under Marxist ideology. We also wanted to create a perfect society through rigid control of people and ideas, by human effort and without God. Now we see the results.
Tell us about your spiritual pilgrimage.
My mother was a very religious person and truly loved God. When I went to the Orthodox church, I was moved by the beautiful paintings, the wonderful choir music, and the colorful rituals. I felt that God existed. I wanted to understand Him better and to communicate with Him. But I didn't know how to do it, how to make Him real in my life.
Later, as I began to study the paintings at the Hermitage I realized that many of them depicted Christian scenes and characters, and conveyed religious feelings. In my desire to learn more about the background of these paintings, I went to the library and asked for a Bible. But I was told that only those with special permits could read this book.
How did you get access to a Bible?
For years I sought in vain to get one. One day, after I had completed my university studies, I was returning to Leningrad by train and noticed that the man sitting next to me was reading an unusual book. When I asked him about it, he told me it was the Bible. I learned that his name was Vladimir and that he was a Christian. He also told me that he could help me have access to a Bible like his.
We agreed to meet the next Saturday at a metro station. From there we walked a very long way until we came to a small house—a barn really. There was a group of about 25 Sabbathkeeping Christians meeting almost secretly. I took a seat near the door, just in case, because I was afraid of what might happen. But when I listened to the people and felt their Christian love, I decided to come back the next Sabbath.
That was your first contact with Seventh-day Adventists?
Yes. The congregation had approximately 40 members, and with them I started to study the Bible. At first I didn't even tell them my name, but slowly I began to feel part of a family of Christians. It was in that church that I began to understand God and His role in my life. The pastor and I discussed a real problem I faced. My work at the Hermit-age did not always allow me to come to church on the Sabbath. So we decided to postpone my baptism until that matter could be resolved. For 15 years I kept going to that church as frequently as I could.
When did you finally get your own Bible?
In the mid-1980s. A foreign visitor came to our church and brought with him one Russian Bible. He gave it to our pastor, and the pastor in turn gave it to me as a present. Then in 1991 an Adventist pastor from Portland, Oregon, came to St. Petersburg to hold a series of evangelistic meetings. He baptized me, and so I formally joined the Seventh-day Adventist Church.
How would you describe the status of Christianity in Russia today?
For years communism tried to stamp out Christianity in our country. Their leaders destroyed or desecrated many of our churches, but they couldn't destroy the faith in Christian hearts. There were always people who loved God and, in spite of many difficulties, hoped for better days. Since perestroika we have been enjoying increasing freedom of religion. People have been able to read the Bible and attend churches without fear.
What about the Seventh-day Adventist Church?
Russia is the largest of the 15 republics that made up the former Soviet Union, now called the Confederation of Independent States. In Russia itself, we have approximately 40,000 members in a country of about 150 million people.
What about St. Petersburg?
We have four congregations in the city. The one where I am a member is located downtown and has about 400 members. We are in the process of building our own church, with assistance from Adventists in the United States.
What are the challenges our church faces in St. Petersburg?
A physical facility, yes. We are on our way to having it. More than that, we must build a temple in our own hearts. We need to anchor our new members in the truth and create a stronger sense of community among ourselves. Only then will we be able to effectively share the truth about God with the five million inhabitants of our city. Many of them are intelligent, well-educated people who are seeking knowledge and a new under-standing of life. With the economic changes that have taken place in the past few years, there is a great deal of uncertainty and discouragement among the people, and we could give them hope. I dream of our church becoming a center for counseling, education, and training for a better life. Young people, particularly, need guidance and help, which our church can provide.
This is your first visit to Adventists outside of Russia. What impressions will you take back with you to St. Petersburg?
I was surprised to find so much openness and friendliness. My brothers and sisters in Christ welcomed me to their churches, schools, and homes. They treated me as if they had known me for years! Although I had come from far-away Russia, they truly made me feel as a member of the Adventist family. I will never forget their Christian love and kindness.
Interview by Humberto M. Rasi. Humberto M. Rasi is director of the General Conference Education Department and editor of Dialogue. Alexei Sergeev's address: Kamennoostrovsky Pr. 39, Apt. 19: St. Petersburg; 197022 Russia. |
Meaning of “ring a bell” in the English Dictionary
british dictionary
"ring a bell" in British English
See all translations
ring a bell
also ring any bells
C2 to sound familiar:
The name rang a bell but I couldn't remember where I had heard it before.
No, I'm sorry, that description doesn't ring any bells with me.
(Definition of “ring a bell” from the Cambridge Advanced Learner’s Dictionary & Thesaurus © Cambridge University Press) |
a few short years ago definition, a few short years ago meaning | English dictionary
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1 of little length; not long
2 of little height; not tall
3 of limited duration
4 not meeting a requirement; deficient
the number of places laid at the table was short by four
5 postpositive; often foll by: of or on lacking (in) or needful (of)
I'm always short of money
6 concise; succinct
7 lacking in the power of retentiveness
a short memory
8 abrupt to the point of rudeness
the salesgirl was very short with him
9 (Finance)
a not possessing the securities or commodities that have been sold under contract and therefore obliged to make a purchase before the delivery date
b of or relating to such sales, which depend on falling prices for profit
10 (Phonetics)
a denoting a vowel of relatively brief temporal duration
b classified as short, as distinguished from other vowels. Thus in English (ɪ) in bin, though of longer duration than (i:) in beat, is nevertheless regarded as a short vowel
c (in popular usage) denoting the qualities of the five English vowels represented orthographically in the words pat, pet, pit, pot, put, and putt
11 (Prosody)
a denoting a vowel that is phonetically short or a syllable containing such a vowel. In classical verse short vowels are followed by one consonant only or sometimes one consonant plus a following l or r
b (of a vowel or syllable in verse that is not quantitative) not carrying emphasis or accent; unstressed
12 (of pastry) crumbly in texture
See also shortcrust pastry
13 (of a drink of spirits) undiluted; neat
14 have (someone) by the short and curlies
Informal to have (someone) completely in one's power
15 in short supply scarce
16 short and sweet unexpectedly brief
17 short for an abbreviation for
18 abruptly
to stop short
19 briefly or concisely
20 rudely or curtly
21 (Finance) without possessing the securities or commodities at the time of their contractual sale
to sell short
22 caught or taken short having a sudden need to urinate or defecate
23 fall short
a to prove inadequate
b often foll by: of to fail to reach or measure up to (a standard)
24 go short not to have a sufficient amount, etc.
25 short of except
nothing short of a miracle can save him now
26 anything that is short
27 a drink of spirits as opposed to a long drink such as beer
28 (Phonetics, prosody) a short vowel or syllable
29 (Finance)
a a short contract or sale
b a short seller
30 a short film, usually of a factual nature
31 See short circuit 1
32 for short
Informal as an abbreviation
he is called Jim for short
33 in short
a as a summary
b in a few words
34 See short circuit 2 (See also) shorts
shortness n
long-and-short work
n (Architect) the alternation in masonry of vertical and horizontal blocks of stone
Pepin the Short
n died 768 a.d., king of the Franks (751--768); son of Charles Martel and father of Charlemagne. He deposed the Merovingian king (751) and founded the Carolingian dynasty
short account
1 the aggregate of short sales on an open market, esp. a stock market
2 the account of a stock-market speculator who sells short
adj (of a drug) quickly effective, but requiring regularly repeated doses for long-term treatment, being rapidly absorbed, distributed in the bloodstream, and excreted
Compare intermediate-acting long-acting
short bill
n a bill of exchange that is payable at sight, on demand, or within less than ten days
vb tr
1 to give less than correct change to
2 Slang to treat unfairly or dishonestly, esp. by giving less than is deserved or expected
short-changer n
short circuit
2 to develop or cause to develop a short circuit
3 tr to bypass (a procedure, regulation, etc.)
4 tr to hinder or frustrate (plans, etc.), (Sometimes (for senses 1, 2) shortened to) short
short corner
n (Hockey) another name for penalty corner
short covering
1 the purchase of securities or commodities by a short seller to meet delivery requirements
2 the securities or commodities purchased
short cut
1 a route that is shorter than the usual one
2 a means of saving time or effort
short-cut , -cuts, -cutting, -cut
3 intr to use a short cut
(C16: from cut (in the sense: a direct route))
adj (of a gilt-edged security) having less than five years to run before redemption
Compare medium-dated long-dated
adj (of plants) able to flower only if exposed to short periods of daylight (less than 12 hours), each followed by a long dark period
Compare long-day
short division
n the division of numbers, usually integers, that can be worked out mentally rather than on paper
short fuse
Informal a quick temper
1 lacking the usual or necessary number of assistants, workers, etc.
2 (Sport) (U.S. and Canadian) with less than the full complement of players
short-handedness n
short head
n (Horse racing) a distance shorter than the length of a horse's head
short hundredweight
n the full name for hundredweight 2
short jenny
n (Billiards) an in-off into a middle pocket
Compare long jenny
(from Jenny, pet form of Janet)
short leg
n (Cricket)
a a fielding position on the leg side near the batsman's wicket
b a fielder in this position
short list (Chiefly Brit)
1 a list of suitable applicants for a job, post, etc., from which the successful candidate will be selected
vb tr
2 to put (someone) on a short list
adj living or lasting only for a short time
short metre
n a stanza form, used esp. for hymns, consisting of four lines, the third of which has eight syllables, while the rest have six
short odds
pl n (in betting) an almost even chance
short order
n (Chiefly U.S. and Canadian)
a food that is easily and quickly prepared
b (as modifier)
short-order counter
adj of small or limited extent in time or distance
a short-range forecast, a short-range gun
short shrift
1 brief and unsympathetic treatment
2 (formerly) a brief period allowed to a condemned prisoner to make confession
3 make short shrift of to dispose of quickly and unsympathetically
1 relating to or suffering from myopia
2 lacking foresight
a short-sighted plan
short-sightedly adv
short-sightedness n
adj tending to be abrupt in speech
adj lacking an adequate number of staff, assistants, etc.
short story
n a prose narrative of shorter length than the novel, esp. one that concentrates on a single theme
short straw
draw the short straw be the person (as in drawing lots) to whom an unwelcome task or fate falls
short subject
n (Chiefly U.S) a short film, esp. one presented between screenings of a feature film
adj easily moved to anger; irascible
1 of, for, or extending over a limited period
short-term credit, short-term capital
n the tendency to focus attention on short-term gains, often at the expense of long-term success or stability
short-term memory
Compare long-term memory
short time , short-time working
short ton
n the full name for ton 1 2
adj unusually short from the shoulders to the waist
short wave
a a radio wave with a wavelength in the range 10--100 metres
b (as modifier)
a short-wave broadcast
1 tending to run out of breath, esp. after exertion
2 (of speech or writing) terse or abrupt
English Collins Dictionary - English Definition & Thesaurus
Collaborative Dictionary English Definition
a short performance
very short haircut
be negatively impacted by a situation, event.
move a short distance, especially while seated
sleep for a short period of time, have a light sleep
Also: payday advance, overnight loan.
happening once a year
Ex.: My favorite annual event is Christmas because I eat my mother's great feast and get christmas presents from Santa Claus.
Or sign up in the traditional way
• Create your own vocabulary list
• Contribute to the Collaborative Dictionary
• Improve and share your linguistic knowledge |
First language: 309–400 million
Second language: 199–1.4 billion
Overall: 500 million–1.8 billion
British Empire
It's the language of the biggest business-related country in the world USA
Most books and handouts are written in English
Internet, Hollywood,
All airline pilots and air traffic controllers have to speak English
[3] Following the British colonization of North America, it became the dominant language in the United States and in Canada
World war ll
the most widespread language in the world
You shouldn't stop at English. Spanish, French, Japanese, German, Russian, Arabic as well as Chinese are all very important languages depending on your area of expertise and where you live
People will think of you in a better way and you will have a better chance of being accepted. You will most likely also have more opportunities in life.
Many English majors have gone to work in a variety of fields, such as business, communications, management training programs, education, advertising, law, and social services.
it opens up a whole lot more opportunities in life
Language of communication for people around the world
Being able to read and write in English is not enough
IF YOU are currently learning English in a school, college or institute of further education, you join approximately one billion other people around the world who are engaged in the same pursuit. However, as you try to memorize proper grammar, and try to avoid the mistakes common to most students of English, you may wonder why you are learning the language in the first place.
Farzad Parsaie
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Identifying Dry Eye Conditions and Treatments
Factors like cold weather and allergies might play a huge function in influencing the dry eye disorder. Experiencing both allergic reactionsand dry eye at the same time, deferentially draw that and figuringout could often be tough, but the soonerthat can be done the faster a individual could begiven a comfort. Entering to seeyour local optometrist and organizing aneye exam will assist get rid of any kind of further damage to your eyes. Getting involved in the allergicreaction season quickly, its attractive outside now and spring time is the classical time when people experience the most allergic reactionsymptoms. The antihistamine that manypeople are taking whether suggested orotherwise suggested orally, have a second side effect of decreasing tear manufacturing and could make the dry eye scenario muchworse, that's why its essential to look for both sides of the range.
When you start an examination to assess the top quality of the tear movie and to examine the evaporation rate of the tear film, that's called a tear break up time, an optician inserts aspecialized dye which allows them to actually measure the length of time that the splits remain in contact withthe eyeball. A swiftly evaporating tear movie is visiting expose the nerves, the sensory nervesof the cornea is going to produce indicators to make the individual uneasy, paradoxicallypeople will typically state that they're eyes are tearing where in the real issueis lack of baseline or upkeep tearing and in actual tearing those encounters are secondary to compensate for thelack of baseline tearing.
Individuals generally utilize words like my eyes are burning, painful and tearing and its not atall due to the solid connection in between the indicators that aperson encounters and the seriousness of the dry eye. There are techniques whichenableour eye doctors(see lenscrafters in northlake) to really determine the osmolarity of the tear film whichstudies have actually shown straight associates the severity of damageand your eye doctor could oversee the treatment progression as a feature of transforming in values of the osmolarity based upon this brand-new system.
There are a substantial variety of call lens clients experiencing dry eyes. Dryness in the eyesis a major reason that people donot have as good a feedback with the call lenses since you haveto assist the call lenses moisture much like you need to support your very own eyes. Many people drop out of contact lenses, yet they do not actually need to.
Among the significant problems that the population encounters is chronic dry eyes, up to 30 % of the population experiences it, everyone doesn't understand there are numerous things that can be done to help and address the disorder like nonprescription synthetic tears, you could boost tear manufacturing with warm compresses and an optometrist could use on schedule plugs that are made to preserve the tear degree and contact with the eyeball.
There are numerous medications that can be utilized to lower the swelling and you can be knowledgeable about environmental protections, there's no explanation for an individual to be awkward any longer.
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How to Cut Roots With a Trencher
Trenchers typically feature an elongated chained blade similar to a chainsaw, though some designs use a round fixed blade similar to a circular saw to create small trenches for laying buried wire. While trenchers are designed for digging through soil, some trencher blades allow you to cut through roots and other underground obstacles as well. Without one of these blades, you might end up damaging the trencher, breaking teeth off of the chain or possibly even breaking the chain itself.
Contact your local utility company or the one-call center for your state by dialing "811" to have any underground utility lines on your property marked. You shouldn't begin work until the lines have been marked to ensure that no buried lines are in the area where you plan to use the trencher. Failure to do so can result in fines and expensive repairs if you damage a buried utility line.
Install a blade with carbide teeth on your trencher, or replace the chain on the trencher blade with one that has carbide teeth. By default, many trenchers use blades or chains with cup teeth that are designed to dig through soil but not solid obstacles; carbide teeth are designed for use with dense soil or soil that has solid obstacles in it such as roots.
Position the trencher blade to one side of the root you want to cut with the blade teeth facing the root at a 90-degree angle. Digging out some of the soil around the root will make positioning easier since you'll be able to see the root clearly.
Start the trencher and slowly lower the blade to begin cutting into the soil. Avoid lowering the blade directly onto the root because the blade won't have soil on either side of it to help stabilize it for the cut.
Walk forward slowly, pushing the trencher blade into the root. Hold the handles of the trencher tightly to stabilize it, pressing forward slowly but firmly to keep the blade moving through the root and surrounding soil.
Push the trencher forward until it cuts completely through the root. Once the trencher blade is completely clear of the root, raise the blade and turn the trencher off.
Repeat the process to cut through other roots or to make additional cuts in the same root as necessary.
Things You Will Need
• Trencher chain with carbide teeth
• Always wear steel-toed boots, eye protection, hearing protection, a hard hat and gloves to protect yourself when using a trencher. You should also wear a long-sleeved shirt or jacket and long pants to protect your arms and legs from dirt and other debris that may be thrown by the trencher blade.
• Shut down the trencher immediately if teeth begin breaking off the blade, the blade becomes stuck or the blade chain breaks. If the root causes the trencher to kick back, shut it down and back out away from the root before starting the cutting process over again.
• Avoid using a trencher to cut through large tree roots if possible since larger roots increase the likelihood of problems with the cut. Although a trencher can be used to cut through roots, it was designed for creating trenches in soil and may not be able to handle large roots.
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Pronunciation of Copula
English Meaning
The word which unites the subject and predicate.
1. A verb, such as a form of be or seem, that identifies the predicate of a sentence with the subject. Also called linking verb.
2. Logic The word or set of words that serves as a link between the subject and predicate of a proposition.
Malayalam Meaning
Transliteration ON/OFF | Not Correct/Proper?
സംയോജികപദം - Samyojikapadham ;സംയോജകപദം - Samyojakapadham ;സംയോജികപദം - Samyojikapadham ;ബന്ധം - Bandham ;ഘടകം - Ghadakam ;സംയോജകപദം - Samyojakapadham ;
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The Large Sagittarius Star Cloud
This is a cropped closeup of the brightest part of the Milky Way. This is part of the galactic hub, the inner region where stars are more tightly packed than they are in these outer regions, and much older as well. These stars are so dense and distant that even a large amateur telescope is unable to resolve them all. Much of the fantastic intricacy of the dust lanes riddling this area is visible through a good telescope. Numerous foreground clusters and nebulae dot the region. Here we are looking through an immense corridor of stars.
Image copyright by Joe Bergeron. |
Thursday, October 22, 2009
Library of Congress: Lesson Plan
In searching the Library of Congress online, I came across a lesson that looked interesting to me. It's title is: Around the World in 1896; and it is a lesson for grades 6 - 8. When I first looked at the lesson I kind of squirmed a bit because it is very intense. However after looking at the length and depth of the lesson, I scrolled back to the top to notice that this lesson is to take place over 3 weeks. Even though it is loaded with information, it still has the core components of a basic lesson. Standards set by the district, student objectives, some form of introduction (background) or engagement, an exploration activity, explanation, an extension to what was initially done, and an evaluation of what the student got out of the assignment.
Yet, because this is coming from the library of congress it also provided a bibliography of primary resources to pull information. In addition, each activity of each step had step-by-step direction of exactly what to do. With good reason, because everything needs to done online so it needs to be very detail oriented. Most regular classroom lesson plans would not this detailed, but I know that when I have a technological lesson and I project it so that all of the students can see I have to be just detailed. It cut down on confusion and it aids in having the students complete the task exactly the way it is supposed to be.
Another thing noticed about the lesson plan, which is good practice for anyone planning on using Internet sources for their student's assignments, is that they hyperlink all online resources exactly where the students are supposed to use it. This is something that I should have done in my Social Media lesson plan, it looks "cleaner" when you do it that way and it definitely leads to better student understanding.
Everyone should take a look at this site and notice the manner in which the lessons are developed. Even for everyday lessons this may be the key for better concept understanding. All the way down to the goals of the assignment which are listed at the end, in which you expect to meet. This gives me a new outlook on planning!
Thursday, October 1, 2009
"Second Life Amendment"
I need to make an amendment to an earlier post that I made about Second Life. I had very minimal knowledge about it and its capabilities...and I still do. However, after being in my Paperless Classroom class tonight, I was exposed to a few of the capabilities and how it can be used as a teaching aid. I mean can pretty much go anywhere at anytime without leaving your computer seat: different parts of the world and even back in time. Again this is something that I would now definitely lobby for in my classroom, it is the perfect way to differentiate instruction by 'what your doing and exposing the students to' and 'how you are doing it,' using technology.
See it, Do it, Teach it!
Eliot, The Waste Land
I think that Eliot ends the poem in the manner that he did to address all parties involved in the war, crossing language barriers identifying the many cultures...
Wednesday, September 23, 2009
Second Life..."Copy Cats!"
I just wanted to take a minute to address the whole supposedly "Wow" factor behind Second Life. We had to create a Second Life avatar for my Paperless class and I totally understand the idea behind setting it up, for the same reason we have our other social networking stay in touch with all available resources out there. However, I think that this site took away some of the immediate enjoyment. One, I think it's a "SIMS" low-budget knock off, and when you first pick your avatar you cannot even customize it. Mine faintly resembles me, but that's only because he's bald, black, and has facial hair. I feel more impressed by my "Yahoo" avatar. And it makes my computer run slow...
Saturday, September 19, 2009
Why do I teach?...Why do you teach?
Does that title sound aggressive enough? <Laughing> No, that was not to ruffle any feathers, but that question has been in my mind a lot lately and you know what, I don't stumble or hesitate with my answer.
My goal in life was to always 'help' people, whether it was through researching the latest biomedical therapies for Alzheimer's disease, kicking down doors to arrest the man responsible for beating his wife, or what I have found to be the root of a lot of the problems facing today's society; children (our students) not having consistent role models. Teacher's make a great impact on students and it can be either positive or negative, and they have a lot of time to make that impact. Teacher's spend approximately 7 to 8 hours with there students, I would say we spend the same, if not more awake time with our students than their parents spend with them. So I would say that it is a piece of our responsibility to help create productive, respectable adults out of these young men and women.
I think that it's time for our teachers to stop taking things so personal. And not necessarily with the kids, I have seen some of the best teacher's in a lot students lives leave schools because of a personal issue with another teacher or an administrator...SELFISH! Just as a reminder we are adults, and we are not here for other teachers or the administration, we are here for the students and the students only.
So, to answer the question: "Why do I teach?" Well, it's actually very simple...,but first let me say this, I am the product of a broken home, raised primarily by my father. I'm not from the city, I'm from a county suburb. However, I have spent a lot of time in the city growing up visiting with family and my college is in the middle of East Baltimore, where it gets pretty real as soon as you step off of the side walk. In addition to that I have seen a lot and done a lot all across the country, as well as having enriching careers that have taught me a lot usable physical and critical thinking skills. And that little tangent <laughing> IS actually why I teach and where I teach, because I know first hand what lies before our inner city youth; and because they may not have a male figure in there life to share those experiences so they can have a good idea of how to handle things (and have a conscious) to guide them through life and provide an education at the same time. Huh, and you know what? I will now and forever take that role.
So, why do you teach...?
Respectfully yours,
Thursday, September 10, 2009
Give them enough rope to choke themselves...or maybe not...
So, this year I have taken a new approach to teaching, and "my kids" know what that approach is (I never keep anything from my students)...I am giving them a lot more responsibility. I told them from day ONE of this school year, I'm not chasing them around for their work and you are going to be solely responsible for completing and turning in quality work. I even went against my own rules and told them that they have a pinch of my trust, so don't "JACK" it up.
I have a combination of (2) classes this year general 8th grade Science and Science Technology, also for my 8th grader's. So I immediately delegated out the responsibility of them having to email their first assignment to me because I know they all have a genuine interest in computers, and I got 100% participation (I was surprised). That was truly a good demonstration because once they had my email address they began emailing me about other assignments so that they can receive help at anytime about anything.
Now we are working in the classroom for several days in a row to make sure they can keep that ball rolling outside of the tech lab. It truly lightened my heart when I saw my students carry over their habits from the tech lab in to the "lecture/lab" class. It ran like clock work: they get a demonstration, they get a guided assignment where they can "shoot" me all sorts of questions, then they get their assignment and they are working, period. Something new that I am glad that I am seeing this year (I taught these students last year too) is that they are helping each other without me having to mandate it, and they are really learning from each other. It sometimes even evolves to an open discussion amongst themselves with me only acting as a facilitator.
I'll tell you what, I hope this lasts throughout the school year because if it does I can predict a lot of higher learning and critical thinking going on. We will see, they are either going to choke themselves out with all this responsibility, or they are going to use that rope to take that responsibility and pull themselves to the "next level" with it!
Sunday, September 6, 2009
My Shocking discovery of students take on Social Networking in the Classroom
So, it's Friday morning...maybe about ten minutes or so before the end of class. A few of my stellar students have finished with their assignment and as much as they try to hide them I still manage to see their cell phones out! As I walk over to them, they notice that I see their phone so they prepare to lose their phone for the rest of the day (I taught these students last year, so they already know that I take phones). To there surprise, I come over and say "Let me see your phone?" I told them that I don't want to take it, I just want to see it. I asked them if they could get on to the Internet, and they were like "Of course!" I told the young lady to get on to for me, as she was doing that I was explaining to what became a small group of students about what we were doing and trying to accomplish in my Paperless Class at Johns Hopkins University. I was explaining that we could use this tool for participating in class so that students that usually don't participate can put their ideas out there without the fear of "being wrong..." And the kids immediately chimed in on that. When I logged in to twitter from my students phone I was able to show them what I was talking about exactly, and they began to see the reality of the idea and I wasn't just "bluffing" them. With what I was able to explain to and show them it opened to a class discussion. So the first thing that a student mention was that what if everybody doesn't have a phone that can get on the Internet, so one of my other students shouted out, "well if enough people have Internet phones, we could share, type on to the screen: then what they have to say after." I was very surprised to hear that and even more so everybody agreeing with the idea. Then another student took it to another level with another suggestion, she said that we could twitter questions and comments for students while they were doing presentations to be asked and as a form of participation & notes. I was very impressed with scholarship and maturity of that comment. With the district's filtering system on the school's Internet and the administration's choke hold on cell phone being on school property, I don't know what the next step is for these students and the use of a Social Network in the classroom. What I do know is that when we do get to that next step I have a good amount of students that will be ready! |
The VICE Channels
You Can Now 3D Print with Metal at Home
Written by
Derek Mead
An action shot of the welder-powered printer, courtesy Michigan Tech
Dazzle someone with a tale of the 3D-printed future, where everyone, everywhere prints their own goods at home, and after the initial surprise that you can print anything from math tools to body parts wears off, you'll hear the same question: This is cool, but does it only print plastic?
Plastics may be the future, but they're not the perfect materials for everything we need. The holy grail of 3D printers is a model that can print a multitude of materials at once—imagine printing a working cell phone—but for now, it'd be nice to be able to print some good old-fashioned metal. Extremely costly options exist, but engineers at Michigan Technological University have developed a metal 3D printer that can be built for less than $2000.
"Metal was the last class of material that the low-cost open-source 3D printing community needed to complete their collection," Joshua Pearce, an associate professor at Michigan Tech's Open Sustainability Tech Lab and a co-author of a paper outlining the work to be published in IEEE Access, wrote in an email. "This helps us take one more step down the path to 'printing everything.'"
Metal parts are largely shaped by one of a trio of processes—casting, forging, and machining—or some combination of all three. Printing metal—that is, building a structure by fusing layer after layer of material—is more difficult than plastic largely because plastics can have lower melting points. Working with rapidly heated and cooled ABS plastic is less of an endeavor than developing a printer head that can work with molten iron.
The welder lays down material on the 3-axis stage, via the paper
But an off-the-shelf machine that spits out clean lines of molten metal already exists: a MIG welder, which spools out a wire electrode that's melted as part of the welding process. The team developed a system for automatically controlling the arc and speed of the welder's electrode, which is laid down in beads that act as the printed layers.
Rather than moving the welder like a print head, the team developed a computer-controlled platform that moves in three axes. (The analogy that comes to mind is moving an ice cream cone under a soft-serve nozzle to build up a massive swirl.) By moving the stage under the bead laid down by the welder, the printer is able to build up layer after layer of printed metal.
The team demonstrated the printer's viability with a water-tight cup design—which showed that the metal indeed fused together—as well as a sprocket shape. While the final results of durability tests aren't yet in, initial measurements show the team's printed products are far from flimsy.
"We haven't completed the full gauntlet of mechanical tests yet, but they are solid steel objects you are printing," Pearce said. "You would not want to print a ball and play catch, as it would certainly hurt to get hit with it."
Better yet, the design is open-source and runs on Linux-powered microcontrollers. To make things even easier, the printer adheres to RepRap self-replicating standards, which means the printer "runs on free software, has free and open hardware designs, requires no specialized training in welding and existing self-replicating rapid prototypers can print the primary custom components necessary for its fabrication," the team wrote.
"Utilizing the open-source hardware concept used in the RepRap community enabled us to develop the metal 3D printer in weeks rather than years," Pearce said. "Under this paradigm we are obligated to share our improvements back to the community."
"This is something we are happy to do because we can be assured that the global maker community is already hacking the concept and developing improvements on our design or applying the concept to other types of RepRaps," he added. "Making a technology open source simply helps it develop faster."
Instructions for the design, including a shopping list and open-source firmware for the various controllers needed, is available on Appropedia. The hope is that just about any hobbyist with a modicum of hacking experience, access to a 3D printer to print the specialized parts, and a couple grand sitting around could build the MTU team's design. Compared to commercial metal 3D printers that cost hundreds of thousands of dollars or an equally-costly 5-axis CNC machine, it's a much lower barrier to entry to creating custom, complex metal parts.
"I see three core applications: First, small businesses will finally have access to metal prototyping and small batch production of metal 3D printed products, which will radically drop costs while also likely reducing environmental impact similarly to what we have seen for plastic RepRaps," Pearce wrote. "Second, the developing world can use the printers to fabricate appropriate technology for sustainable development at extremely low costs. Finally, scientists will be able to digitally fabricate metal components of low-cost scientific equipment making 'open source labs.'"
Behold a cheaply printed sprocket. Via the paper
In the paper, the team notes that the concept isn't perfect just yet. Aside from needing to develop built-in safety features—with a full-on welder in play, it's far from a self-contained desktop system like a MakerBot—there are some practical hurdles to clear.
For one, the system can't yet print horizontal holes, which requires a method for building a "bridge" across gaps in layers. There may be a firmware solution, but it also relates to a second problem: the printer's resolution is limited by how thin the welder's wire material is. The team plans on moving to the thinnest commercially available wire, which will allow for finer details, but the design means that the precision of decisions is limited by how thin the wire material is.
The team does state that multiple metal alloys could be used with their method. One particularly interesting alloy they suggest is that of aluminum beverage cans, which are widely abundant, accessible, and offer a nice weight-to-strength ratio. Actually utilizing that aluminum stock would likely require creating a more pliable alloy, but for 3D-printing enthusiasts looking to get metal stock on the cheap without buying in bulk, it's an attractive option.
That last point offers a nice glimpse into the 3D-printed future. Today, our manufacturing is locked up in factories, where bulk shipments of raw materials are delivered, transformed, and distributed. But the hope is that a distributed manufacturing network powered by 3D printers could ultimately be more efficient.
"Many of the products we use are dominated by plastic," Pearce said. "It is easy for me to envision us moving to a society where we all have polymer RepRaps in our homes. For metals we would probably rely on a local business or community centers for the few times we needed metal components."
So instead of getting your spork shipped from China and stored in a warehouse, you print it when you need it. And instead of ordering a replace sprocket for your bike, your neighborhood metal printer could produce it with material from your local aluminum recycler. It's a fascinating concept, and one that continues to inch closer to reality. |
Nil by Mouth sessions get under the skin of the issue: challenging preconceptions and asking people to ask as many questions of themselves as they do of others
“Sectarianism?” This word is used to describe a “sect”, or section within an established group, but most commonly it’s used with regard to groups with a particular religious or political basis.
The word sectarianism is very often used in Scotland today in association with divisions within a religion, particularly in reference to Christianity and the division which can exist between Catholic and Protestant people. Sectarianism can also be found within other religions.
As society becomes increasingly secular, the term is often also used to describe a type of social identity, that is about things other than a particular set of religious beliefs.
The Reformation movement of the 16th century saw Protestantism, a new type of Christianity, sweep across western Europe. The various leaders of these emerging groups had beliefs and ideals which were not in keeping with the practices and belief systems of the traditional Catholic Church of Rome. There was considerable public support for this movement in Scotland, once a predominantly Catholic country. Protestantism was later adopted by the state as Scotland’s national religion with various strands and movements emerging over time .
The 17th and 18th century saw conflict between the Jacobite followers of Catholic King James VII and the forces of King William and Queen Mary, who took the throne in 1688 and were not Roman Catholics. In the 19th century the prospect of Jacobite invasion declined, yet sectarian conflict continued as a result of immigration of those who later fled famine in Ireland ( a traditionally Catholic country) and sought to live and work in Scotland. Urban industries and expanding transport systems offered opportunities for work in factories, and in building railways, canals, bridges and roads.
As we have seen throughout history, a large scale movement of people from their homeland often causes social tensions, and those new to a country commonly create support networks with each other for support. Some areas in cities, such as Edinburgh’s Cowgate and Canongate were called “Little Ireland” due to the congregation of immigrants living there. Many Irish Catholics settled in the poor east end of Glasgow, and in communities across the west of Scotland in particular, seeking work in industries such as mining and textiles. These settlements led to increased competition for employment and housing and this sometimes led to antagonism and conflict between competing groups of workers over housing and jobs.
Widespread discrimination in entering employment, and certain established social networks, also fuelled tensions between the Catholic and Protestant communities in Scotland. Employment opportunities were denied to people of both denominations on the grounds of the religious group to which they belonged or were perceived and prejudged to belong. Discriminatory recruitment practices were conducted both officially and unofficially and a name considered traditionally Protestant or Catholic, or whether a candidate attended a Catholic or non-denominational school, was sufficient grounds for many businesses to exclude people from employment.
Sports clubs were founded as a focal point for these Irish immigrant communities. For examples, Hibernian Football Club was founded in Edinburgh in 1875, and Glasgow Celtic Football Club was established in 1888. Later, in Dundee, Dundee Hibernian later became Dundee United. Football teams, whether they developed from a mainly Irish Catholic or Scottish Protestant community or neither, played matches between one another for charities and to win competitions. Today, the increasing diversity of Scotland’s population means that no football clubs are in the same way tied to any particular religion, and players and supporters of all teams will be from a range of racial, ethnic and religious backgrounds to a greater or lesser extent.
In recent years, the challenge against sectarianism in Scotland has made some difference to what is a deep rooted and widespread social issue for us. The problems associated with religious conflict are being examined and confronted across society by schools, community groups, academics, football clubs such as Celtic and Rangers, football governing bodies, national and local governments, churches, charities, museums, galleries and a growing number of individuals across the nation. However – you will still hear the offensive language on our streets, at football matches, on public transport, in pubs and social clubs, and in some people’s homes. You will still see graffiti about Irish Politics in some places in Scotland, you might still be unwelcome at the local golf or bowling club because of your surname, and when you marry someone whose family are from a different “sect” within Christianity you might still to this day experience more disapproval than you had expected to.
Cultural and economic landscapes change, and while the Scotland we live in today is a small country striving to be competitive and modern, it still has work to do in addressing some negative and harmful old-fashioned views. |
our everyday life
How to Make Someone Who Doesn't Speak English Well Feel More Comfortable
by Sandra L. Campbell
With more than 300 million people within its borders, the United States is an ethnically diverse country, which includes native and nonnative speakers of English. In 2010, 25.2 million people age 5 or older had limited English proficiency, according to a March 2012 article on the Migration Information Source website. Nonnative speakers can have difficulty communicating with coworkers and friends. But a person struggling with English doesn't have to feel alone. With a few helpful techniques, a caring friend or family member can ease their discomfort.
Slow it Down
Pronounce every word. Remember to pause and give the nonnative speaker a chance to formulate an appropriate response, according to an article on the Cultural Awareness International website, "Communicating Effectively With Nonnative Speakers." Avoid idioms or slang words. Expressions common to Americans may mystify a nonnative speaker. For example, "Hang a left on the next street," might confuse someone who doesn't speak English fluently. Use short, simple phrases: "Do you like movies?" or "This restaurant serves good food."
Understand the Person's Culture
Nonnative speakers can experience "culture shock" when they come to the U.S. for the first time. Culture shock symptoms include indecision, passivity, homesickness and depression, according to an article on the Brigham Young University Linguistics and English Language site, "Cultural Considerations." Help the nonnative speaker feel more secure by becoming educated about her culture and language. What are the native traditions in her country? What are her traditional foods? If the nonnative speaker is from Spain, one popular dish from that country is paella, made with rice, seafood and assorted vegetables. Try making the dish together. Also, some nonnative speakers use varying degrees of verbal and nonverbal communication. For example, in some countries, people stand close while speaking. In the United States, a typical American will put distance between herself and the other speaker. Integrate this new knowledge about the person's culture into conversations. This will put the person more at ease about her language proficiency.
Introduce Other Language Learners
Nonnative speakers who feel insecure about their language proficiency will shy away from social situations. Counteract this by introducing them to other English learners. Language learners may be at different levels of English proficiency but are usually eager to help support a nonnative speaker. Additionally, introducing language learners from the same country can go a long way in helping a nonnative speaker feel more comfortable.
Shake Up Entertainment Activities
If entertaining a person who doesn't speak fluent English, try an innocuous activity, such as watching a movie. Make it a movie and a dinner and be sure to use subtitles in the person's language. Try to use the moment as an opportunity to discuss how some words in English translate differently in other languages. Choose activities that don't require much talking, such as going to the zoo, looking at fine artwork or listening to live music. In other words, select activities that have universal appeal. This will engage the person and make her feel more accepted among other native English speakers.
About the Author
Photo Credits
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Anxious fathers make caesarean ops more painful for mothers
Helping prepare the birth partner for a caesarean could help reduce the pain experienced by the mother
Fathers who are anxious during a caesarean operation may increase the pain experienced by the mother after the delivery of their baby, according to new research published in the journal Psychosomatic Medicine.
In a study involving 65 women scheduled for an elective caesarean, researchers found that the way their birth partners felt during the operation was related to the woman's own levels of fear and anxiety about the operation.
The lead researchers from the University of Bath (Dr Keogh) and Imperial College London (Dr Holdcroft) suggest that helping prepare the birth partner for a caesarean, both at antenatal classes and before the operation, could help reduce the pain experienced by the mother and improve the birth experience.
One in four babies born in the UK is now delivered by caesarean section (CS), with many hospitals delivering almost 30 per cent in this way. Fear of pain during childbirth is often cited as one of the contributory factors for the increasing rate of CS delivery.
"Caesarean sections involve major surgery and are often performed whilst the mother is awake under regional anaesthesia which numbs the lower part of the body," said Dr Ed Keogh from the University of Bath.
"Whilst actual pain during a caesarean is usually more controlled than a vaginal delivery, the whole procedure is not painless.
"Women who have had a caesarean tend to experience much longer periods of postnatal pain and recovery. They also have mobility restrictions placed on them whilst they recover from the surgery, such as picking up heavy items, reaching upwards and driving.
"Whilst it has become a social expectation that birth partners accompany and support mothers during a caesarean delivery, it is unclear what part birth partners play in women's experience of childbirth.
"Whilst some women say that birth partners improve birth experiences, others report less positive outcomes. It is not unreasonable for the birth partner to have some feelings of anxiety and fear about the operation they are about to witness."
The women involved in the study were recruited from the Chelsea and Westminster Hospital in London during regular ante-natal check ups.
Almost all of the women (61) had chosen their husband or partner to be their birth partner, with just four deciding on a female birth partner.
The women and their birth partners were questioned before, during and after the delivery about their fears, expectations and experiences. The women were also assessed for their pain levels at different stages of the procedure and immediately afterwards.
The study revealed that those women who had negative birth expectations before the operation had the most fear experiences during the delivery, which in turn was related to greater post-operative pain.
It also showed that women are most afraid during the application of the nerve block used to numb the lower part of the body, rather than the initial incision as the researchers expected.
"Maternal fear fluctuates during a caesarean section but it can be influenced by the psychosocial factors around them, including their birth partner," said Dr Keogh.
"Anecdotally a number of birth partners told us that they had little choice in attending the caesarean operation and felt ill prepared.
"Birth partners can have potentially beneficial effects on maternal birth experiences. Rather than removing them from the operating theatre altogether, it would be better to target the emotional wellbeing of the birth partner to help reduce the anxiety and fear experienced by the mother.
"Since anxiety can increase recovery times, it would be useful to study whether increased maternal fear during the procedure has an impact on mothers, such as longer-term recovery from surgery as well as other related factors such as breast feeding and parent-child bonding."
Published on All rights reserved. |
Nervous And Endocrine Systems: Question Preview (ID: 3821)
Below is a preview of the questions contained within the game titled NERVOUS AND ENDOCRINE SYSTEMS: Hormones And Glands, Nerves, Spinal Cord And Brain .To play games using this data set, follow the directions below. Good luck and have fun. Enjoy! [print these questions]
What part of the neuron carries nerve impulses away from the cell body?
a) dendrite b) cell body c) axon d) synapse
what is the space between an axon and the next structure?
a) axon b) synapse c) dendrite d) nucleus
In a reflex skeletal muscles react without the involvement of the
a) motor neurons b) sensory neurons c) spinal cord d) the brain
A motor neuron sends an impulse to
a) interneuron b) the brain c) muscle d) spinal cord
The brain and spinal cord make up the
a) peripheral nervous system b) central nervous system c) somatic nervous system d) autonomic nervous system
A bruiselike injury to the brain is called a
a) concussion b) abrasion c) paralysis d) stimulant
The endocrine system acts on the body through chemical products called
a) blood b) saliva c) hormones d) target cells
The endocrine system
a) does not begin to function until puberty b) controls body activities through reflexes and nerves c) produces chemicals that travel to locations through tiny tubes d) control both daily activities and long-term changes through hormones
The sense organs send information about the environment to the
a) interneurons b) autonomic nervous system c) brain d) hormones
Why do hormones cause changes only in specific body organs?
a) A hormone is carried to a specific location through tiny tubes b) A hormone is produced only where it is needed. c) A hormone works only through negative feedback. d) A hormone interacts only with target cells, which fit together with that hormone.
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Xul Solar's Possible Futures
By Alexander Keefe
Pan-Arbol (1954)
Only collective inventions have any real value, Xul Solar once told his close friend and fellow Porteño Jorge Luis Borges, trying to convince him (unsuccessfully) to write in Neo-Criollo, one of the two languages he had invented and the one he himself preferred to use for writing and conversation. Such was the importance to Solar of friendship, sodalities esoteric and otherwise, and cooperation. These days the artist, who died 50 years ago this month and whose close friendship with Borges is at the heart of an ongoing exhibition at the Americas Society in New York, is remembered less for his hermetic, often illegibly coded mystical watercolor paintings than for the collective séance that he made of his particular corner of Buenos Aires' cosmopolitan avant-garde of the 1920s and the decades that followed. But this emphasis on the collective nature of invention also acts as a connecting thread—an axis around which to organize Xul's otherwise deeply idiosyncratic mundus. His diverse ideas and projects—his "Pan-Chess," an antipodean Glasperlenspiel that combined language, numerology and astrology; his invented languages and religions and piano keyboards and mathematics; his cosmic vision of the American future, floating somewhere between the pre-Columbian and the post-Sputnik—all point to the irresoluble paradox at the heart of the artist's techno-utopian vision, at once impossibly scaled and communal, and yet at the same time deeply, even inaccessibly idiosyncratic.
Sometime around 1957 Solar, who was born Óscar Agustín Alejandro Schulz Solari, proposed to do a series of articles for a Buenos Aires-based magazine called Mirador: Panorama de la Civilización Industrial. These would mark the culmination of a body of technological research he had pursued since the early 1940s, delineating a vision of the future at once utopian, post-human and profoundly unsettling. One text, "Autómatas en la historia chica" ("Automata in the little history"), presented an eccentric history of robotics, tracing its evolution from the steam-powered mechanical pigeon described by ancient Greek philosopher Archytas in the fourth century BC, through the brazen heads of medieval wizards, to Solar's own post-war present and the advent of what he called the “new Prometheus.” This latter stage was characterized by factory machines with “pincher-fingers” “that feed on electricity,” destined to free mankind from the necessity of labor.
In his article for Mirador, the author provided an autobiographical note, calling himself, among other things, a "painter, writer and little else.…Re-creator, not inventor, and world champion of Pan-chess and other serious games that almost nobody plays; father of a Pan-language that is meant to be perfect and almost nobody speaks and godfather of another, vulgar tongue without a vulgus; the author of useful grafías that almost no one reads, exegete of twelve (plus one universal) religions and philosophies that almost no one listens to."
If he sounds a bit disillusioned, one can hardly blame him: in the end, "Automata in the little history" was the only article of his proposed series that Mirador agreed to publish. But two others survive from the same period, and together they comprise an unusual, if fragmentary, glimpse into Solar's vision of possible futures. As the Second World War raged and then the Cold War simmered, Solar was contemplating cyborgs and celestial cities.
"Proposals for a future life. Something semi-technical on anatomical improvements and new beings," published in Lyra magazine in 1957—and illustrated with three of Solar’s visionary watercolor paintings from 1935-1936—imagines a post-human world of hybrids, mestizos—to use Solar's word—at once whimsical and disturbing: communal wet-nurses with tremendous breasts branching "into multiple tubes or natural tentacles (…) some longer than others, up to several meters, in order to accommodate even the most distant sucklings of the numerous brood;" men endowed with "a muscular tail of some kind (…) long and prehensile, capable of supporting the body like a third arm"; or the development, through careful breeding and technological enhancement, of arms like "parachute cords, or better yet wings."
Two Mestizos of Airplane and Human (1935)
One of the three illustrations for "Proposals for a future life" is a painting from 1935 called Two Mestizos of Airplane and Human—another is one from 1936 titled, in Solar’s own Neo-Criollo language, Vuelvilla, or The Flying City. The latter painting also gave Solar the title for the third of his texts from the late 1950s, in which he imagines a liberated, airborne metropolis, a techno-utopia held aloft by enormous gas-filled balloons and moving with the wind, its inhabitants beyond race, creed and national border. Solar described them as "just below the zenith, as in the book of Revelation, chapter 21, verse 2: 'And I, John, saw the holy city, the New Jerusalem, coming down from heaven, from God, prepared as a bride adorned for her husband.’"
The artist's interest in new technologies and their implications may seem to be at odds with the way he is usually understood: as avant-garde occultist and proto-New Age demiurge playing the enigmatic gadfly and cosmic prankster to Buenos Aires' potent generación martinfierrista. But Solar’s techno-utopianism combined a destabilizing Rabelaisian grotesquerie with pulp sci-fi speculation and a post-religious mystical reconstitution of the world, making it very much synthetic and of a piece with his broader ludic metaphysics.
A. Xul Solar. “Propuestas para más vida futura. Algo semitécnico sobre mejoras anatómicas y entes nuevos”. Lyra . Buenos Aires, a. 15, n. 5, 1957, p. 31-33.
Alejandro Xul Solar. “Autómatas en la historia chica”. Mirador . Buenos Aires, n. 2, junio 1957, p. 37.
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Robotic Arm Position Control
R/C servo motors are closed-loop systems, and they are inherently useful in arm systems where precise position control of the joints is necessary. But what about when using other types of motors, including DC gear motors and stepper motors? What problems do these open-loop systems cause?
At the very least, you should supplement any open-loop servo system with limit switches. These switches provide an indication when the arm joints have moved to their extreme positions. These can be simple momentary push-button or leaf switches.
You can also construct optical switches using photointerrupters. A small patch of plastic or metal interrupts the flow of light between an LED and a phototransistor, thus signaling the limit of movement. You can build these interrupters by mounting an infrared LED and phototransistor on a small perforated board. Chapter 43, “Proximity and Distance Sensing,” discusses the concepts of using infrared light to detect objects.
Best yet is to provide some type of feedback to report the position of the arm. Otherwise, the control electronics will never know where the arm is or how far it has moved. There are several ways you can provide this feedback. The most popular methods are (in order of difficulty and expense) a potentiometer, an incremental shaft encoder, and an absolute shaft encoder.
Using a Potentiometer
A straightforward method of providing position feedback is to attach the shaft of a potentiometer to the shoulder or elbow joint or motor. As the joint turns, it moves the pot, which in turn changes its resistance. This resistance change indicates the precise position of the joint.
Just about any potentiometer will do, as long as it has a travel rotation the same as or greater than the travel rotation of the joints in the arm. Otherwise, the arm will go past the internal stops of the potentiometer, and the pot will be damaged. Travel rotation is usually not a problem in most arm systems, where joints seldom move more than 40° or 50°. If your arm design moves more than about 270°, use a multiturn pot. A three-turn pot should suffice.
Rotary potentiometers are the most common type, but another style is the slide pot. You operate a slider pot by moving the wiper up and down, rather than by turning a shaft. Slide pots are ideal when you want to measure linear distance, such as the amount of travel (distance) of a chain or belt.
Selecting the Potentiometer Value and Type
The exact value of the potentiometer is not important, but it should be in the 50 kΩ to 250 kΩ range, just for ease in interfacing with your electronics. Be sure the pot is linear taper, and not audio taper. The difference has to do with the resistance scale of the pot.
Connection to Electronics
The potentiometer may provide a relative measurement of the position of the arm, but the information is in analog form, as a resistance or voltage, neither of which can be directly interpreted by a computer. The most common—and generally most useful—way to connect the pot to a control circuit is to use the component as a voltage divider. As the pot turns (or slides), its output is a continuously variable voltage from 0 to the positive supply voltage (usually 5 volts).
The wiper of the pot is connected to the input of an analog-to-digital converter (ADC), which translates voltage levels into bytes. Many modern microcontrollers have built-in ADCs, saving you the trouble of wiring up a separate analog-to-digital converter chip.
Using an Incremental Encoder
An incremental encoder is an optical or mechanical device that counts pulses generated by a disc as it turns. They are frequently used with the drive motors on robots to determine distance of travel.
They’re often called shaft encoders because they’re typically connected to the shaft of the motor they are measuring, though in actual practice the encoder may be coupled with the motor in any number of ways. And they’re known as incremental encoders because they record movement incrementally—one step, click, or pulse at a time. (They’re like a walking pedometer, where every time you take a step it increments a counter.) Figure 1 shows an example incremental encoder disc (also called a codewheel).
[Figure 1]
These kinds of encoders are covered in more detail in Chapter 45, “Navigating Your Robot,” specifically for the task of measuring travel distance and position.
Incremental encoders can be used to measure all kinds of motion, including the rotary or linear motion of arm movement. Internally, the encoder counts the number of pulses; by knowing how many pulses occur in one revolution, you can calculate how far the encoder has turned.
Say, for example, the encoder produces 360 pulses per revolution (for low-cost encoders it’s usually much less than this, but 360 makes the math easier). This equates to one degree of rotation per pulse.
If your control circuit counts 35 pulses, you know the joint has rotated 35°. If your circuit counts 120 pulses, then the joint has moved 120°. Capturing these pulses can be done using a microcontroller like the Arduino, which has an input pin directly connected to a hardware counter.
Using an Absolute Encoder
An incremental encoder simply informs you when there’s motion, and how much, but doesn’t really tell you exact position. You have to infer that through calculation. At the least, every time you power up your robot arm you need to have all the joints return to a “home” or neutral position. From there, you can begin counting pulses and calculating position based on the number of pulses.
An absolute encoder tells you absolutely where something is. Rather than just provide pulses or clicks, an absolute encoder provides a binary output whose number indicates position. An 8-bit absolute encoder provides 256 positions, usually enough for the average homebrew robot arm.
Figure 2 shows a 3-bit encoder disc using a form of binary counting known as Gray code. With three bits, the encoder has a resolution of just seven positions; it’s shown here for the sake of simplicity. In traditional absolute encoder disc designs, bits are added with more tracks. Each track requires its own sensor.
[Figure 2]
While you can make an absolute encoder, the sensing electronics are tricky. You’re best off purchasing one ready-made. Price depends on the technology used in the encoder. There are three basic kinds, in descending order of cost: |
Saturday, January 2, 2010
Exploring SaaS Architectures and Database Clustering
Software-as-a-Service (Saas) is one of the main growth areas in modern database applications. This topic has become a correspondingly important focus for Tungsten, not least of all because new SaaS applications make heavy use of open source databases like MySQL and PostgreSQL that Tungsten supports.
This blog article introduces a series of essays on database architectures for SaaS and how we are adapting Tungsten to enable them more easily. I plan to focus especially on problems of replication and clustering relevant to SaaS—what are the problems, what are the common design patterns to solve them, and how to deploy and operate the solutions. I will also discuss how to make replication and clustering work better for these cases—either using Tungsten features that already exist or features we are designing.
I hope everything you read will be solid, useful stuff. However, I will also discuss problems where we are in effect thinking out loud about on-going design issues, so you may also see some ideas that are half-baked or flat-out wrong. Please do me the kindness of pointing out how they can be improved.
Now let's get started. The most important difference between SaaS applications and ordinary apps is multi-tenancy. SaaS applications are typically designed from the ground up to run multiple tenants (i.e., customers) on shared software and hardware. One popular design pattern is to have users share applications but keep each tenant's data stored in a separate database, spreading the tenant databases over multiple servers as the number of tenants grows.
Multi-tenancy has a number of important impacts on database architecture. I'm going to mention just three, but they are all significant. First of all, multi-tenant databases tend to evolve into complex topologies. Here's a simple example that shows how a successful SaaS application quickly grows from a single, harmless DBMS server to five servers linked by replication with rapid growth beyond.
In the beginning, the application has tenant data stored in separate databases plus an extra database for the list of tenants as well as data shared by every application. In accounting applications, for example, the shared information would include items like currency exchange and VAT rates that are identical for each tenant. Everything fits into a single DBMS server and life is good.
Now business booms and more tenants join, so soon we split the single server into three—a server for the shared data plus two tenant servers. We add replication to move the shared data into tenant databases.
Meanwhile business booms still more. Tenants want to run reports, which have a tendency to hammer the tenant servers. We set up separate analytics servers with optimized hardware and alternative indexing on the schema, plus more replication to load data dynamically from tenant databases.
And this is just the beginning of additional servers as the SaaS adds more customers and invents new services. It is not uncommon for successful SaaS vendors to run 20 or more DBMS servers, especially when you count slave copies maintained for failover and consider that many SaaS vendors also operate multiple sites. At some point in this evolution the topology, including replication as well as management of the databases, is no longer manually maintainable. As we say in baseball, Welcome to the Bigs.
Complex topologies with multiple DBMS servers lead to a second significant SaaS issue: failures. Just having a lot of servers already means failures are a bigger problem than when you run a single DBMS instance. To show why, let's say individual DBMS servers fail in a way that requires you do something about it on average once a year, a number that reliability engineers call Mean Time between Failures (MTBF). Here is a simple table that shows how often we can expect an individual failure to occur. (Supply your own numbers. These are just plausible samples.)
Number of DBMS Hosts
Days Between Failures
Failures are not just more common with more DBMS hosts, but more difficult to handle. Consider what happens in the example architecture when a tenant data server fails and has to be replaced with a standby copy. The replacement must not only replicate correctly from the shared data server, but the analytic server must also be reconfigured to replicate correctly as well. This is not a simple problem. There's currently no replication product for open source databases that handles failures in these topologies without sooner or later becoming confused and/or leading to extended downtime.
There is a third significant SaaS problem: operations on tenants. This includes provisioning new tenants or moving tenants from one database server to another without requiring extended downtime or application reconfiguration. Backing up and restoring individual tenants is another common problem. The one-database-per-tenant model is popular in part because it makes these operations much easier.
Tenant operations are tractable when you just have a few customers. In the same way that failures become more common with more hosts, tenant operations become more common as tenants multiply. It is therefore critical to automate them as well as make the impact on other tenants as small as possible.
Complex topologies, failures, and tenant operations are just three of the issues that make SaaS database architectures interesting as well as challenging to design and deploy. It is well worth thinking about how we can improve database clustering and replication to handle SaaS. That is exactly what we are working on with Tungsten. I hope you will follow me as we dive more deeply into SaaS problems and solutions over the next few months.
P.s., If you run a SaaS and are interested working with us on these features, please contact me at Continuent. I'm not hard to find.
1 comment:
Anonymous said...
Awesome post, this looks like it could be a really good series! Looking forward to the rest.
Scaling Databases Using Commodity Hardware and Shared-Nothing Design |
Paul Slovic
Professor Slovic challenges Professor Viscusi by suggesting that "risk" is a term with varying meanings and the potential for misinterpretation by study participants. He distinguishes between the probability and severity of a risk, and suggests that teens who know the probability of smoking causing cancer are not aware of the severity of the experience of cancer. He goes on to note that people often perceive themselves as being less at risk than others, and observes that Professor Viscusi's study posed questions about others, instead of asking teens to assess their own risks. Thirdly, he argues that teens perceive each individual cigarette as posing a small risk even if they seem to be aware of the larger risk of smoking. Finally, since many teen smokers intend to quit, he contends, they do not see smoking as hazardous to themselves. He argues that Professor Viscusi underrates the misperception of the risks of personal addiction. Professor Slovic augments his argument with original research demonstrating that smoking teens are more likely than nonsmoking teens to perceive the short term risks of smoking as trivial.
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What Is The Citation Project?
The Citation Project is a multi-institution research project responding to educators’ concerns about plagiarism and the teaching of writing. Although much has been written on this topic and many have expressed concerns, little empirical data is available to describe what students are actually doing with their sources. At present, therefore, educators must make policy decisions and pedagogy based on anecdote, personal observation, media reports, and the claims of corporations that sell “solutions.”
The Citation Project begins the process of providing descriptive data. Our team systematically studies student papers that were produced in college writing courses and that draw on sources. Our purpose is to describe how student writers use their sources. With this information, educators will be able to make informed decisions about best practices for formulating plagiarism policies and for teaching rhetorically effective and ethically responsible methods of writing from sources.
Preventing plagiarism is a desired outcome of our research, as the subtitle above indicates, but the Citation Project research suggests that students’ knowing how to understand and synthesize complex, lengthy sources is essential to effective plagiarism prevention. If instructors know how shallowly students are engaging with their research source—and that is what the Citation Project research reveals—then they know what responsible pedagogy needs to address. |
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FIN - Cash Concentration Systems Case
Question;Cash Concentration SystemsFor firms having dispersed collection points, it is necessary to transfer funds from multiple banksaccounts to a single (or just a few) account(s). Conceptually, a cash concentration systemresembles a peer amid in design, moving funds from the broad base within the system (collectionpoints) to the apex (a single account)CustomersCustomersThe operation of the cash concentration system can broke down into three elements:1. The benefits and costs of a cash concentration system2. Methods of transferring funds3. Practical applicationsFirms realize several benefits of having funds located in a single (or just a few) accounts,including greater control, better cash management and investing opportunities, and potentially,the possible existence of positive dual balances when funds are moved between accounts.At the same time, operating a cash concentration system entails several costs, which include:? The administrative costs of managing the system? The cost per item when balances are moved upward within the system? The lost interest realized when funds accumulate in non-interest earning accounts (anopportunity costThe logistics of moving collected balances from the gathering point to the firm?s central bankcan be accomplished by using a mail depository transfer check (largely outdated today), anelectronic transfer via an automated clearing house (ACH), or a wire transfer. Of these three, wire transfers provide near immediate availability but are quite costly compared to ACH,therefore the cost effectiveness of a wire tends to be justified only if the dollar value beingtransferred is considerable. A firm?s cash flow timeline which highlights the basic points withinthe cash concentration system is a good starting point for some practical insights.Cash Inflow TimelineIn the timeline below, points T2, T5, and T6 are noteworthy since the firm possesses real value ateach of these moments. Also of note in this timeline is the existence of positive dual balancesshould be available balance of time T5 occur in advance of the reduced available balance at timeT6.The financial manager can generate increase shareholder value by skillfully controlling the cashconcentration system in several ways:1. Decide upon the optimal transferred to the use. The equation below can be used by thefirm to select the most cost efficient transfer method:Incremental Benefit = DS * [k ? ecr(1 ? rr)] * TBALWhere:? DS = The number of days saved the faster transfer method? k = The firm's investment opportunity rate? ecr = The bank's earnings credit rate? rr = The required reserve rate? TBAL = The balance to be transferredThe incremental benefits equation can be used by the firm to select the most cost efficienttransfer method.The dollar value of TBAL represents the minimum dollar amount of the balance beingtransferred in order to justify the specific tool. That is, while a wire transfer is costly. Bycomparison with ACH transfer, the fund availability at the receiving account is immediate andcan therefore be invested at the firm's opportunity cost rate. As a result, the firm can earn morethan the return earned at the firm?s field bank. Should this not be the case (e.g., if the firm istransferring cure excess balances), the opportunity cost of idle funds at the gathering bank isgreater (since ecr = 0), and the balance being transferred via a wire becomes significantly lower.2. Verify the trade-off between reducing excess balances versus the cost of frequenttransfers. The Total Cost equation is a good starting point to understand the relationshipbetween the goal of minimizing idle balances within the system and the cost of dailytransfers, which would be required to reduce excess balances to zero each day.The term FEE in the Total Cost equation represents the item cost, time AB is transferred betweenaccounts. This item is removed from the service charges (SC) so as to avoid double-counting itas part of SC. The term in parentheses in the equation, therefore, represents the opportunity costof idle balances the field bank whenever ACB > [(SC ? RCB)].3. Calculating the Minimum Balance to Transfer: The financial manager must weigh thecost associated with the transfer method against the amount of the transfer to ascertainthat the costs factor is reasonable. In its simplest terms, as the cost of the transferinstrument increases, the amount to be transferred must be sufficient enough to justify thehigher cost. Referring back to page 2, once you have calculated the Incremental Cost youare now able to calculate the Transfer Balance (TBAL) using the formula below:4. Finally, the cash inflow timeline reveals another value increasing strategy. Since the cashvalues held points T3, T5, and T6 of the timeline above represent real economic value tothe firm, the transfer process may be done in anticipation of the funds reflected at thosetimes. For example, since the firm will in all likelihood earn greater interest income whenit has AB edits concentration account as opposed to AB at the field bank, the transferpoint indicated at T3 can be moved earlier in the timeline in order to expedite the process.It should be noted. Care must be taken. Since only good funds (AB, and not ledgerbalances) can be transferred.
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Supervert » Supervert Essays » Animal Sex Machines
Animal Sex Machines
Analysis by Supervert of the role of bestiality (sex with animals) in contemporary art, particularly in two mechanized works by Paul McCarthy and Mat Collishaw. Originally published in BLAM! 3 CD-ROM (January 1998).
Is animal sex reactionary? Two recent artworks depicting bestiality suggest that there's something anachronistic, something unfashionable about interspecific intercourse. A 1992 sculpture by Mat Collishaw appropriates an infamous turn-of-the-century porn image of a zebra mounting a woman from behind; the image is blown up to the size of a stage flat and the lower half of the zebra attached to a small motor in order to give it a humping motion. The title of the work, In the Old Fashioned Way, implies that people — well, people just don't fuck zebras like they used to. In another bestial work, a sculpture by Paul McCarthy entitled Cultural Gothic, a father decked out in Brooks Brothers attire introduces his preppy son to the fine art of buggering a goat. This 1992-93 sculpture is also mechanized; at various intervals, an air compressor and pneumatic cylinder cause the son's pelvis to thrust at the animal, while the father turns his head and rests his hands in tacit approval on the boy's shoulders. Though obviously parodying Grant Wood's American Gothic, the title captures the irony of contrasts in the work: the bourgeois demeanor of the figures evinces their "culture," while the bestial nature of their activity suggests that they are engaged in something extremely primitive, "gothic" as though American Gothic implied that being down on the farm meant getting down with the animals.
The image of the farmer doing his animals is the very stereotype of bestiality. In his Studies in the Psychology of Sex, Havelock Ellis claims that this is primarily because farmers are incredibly familiar with their livestock and have "primitive conceptions of life" which don't greatly differentiate between men and beasts — between human and inhuman desiderata.1 Bestiality, in this sense, is merely the negative reflection of a question that used quite commonly to plague philosophers: What is human? What does separate man from animal? In the 17th century, for instance, Descartes argued in the Discourse on Method that it is speech and rationality which distinguish man from beast. Later, in the 19th century, Darwin held that man was merely the most complicated or "advanced" being in a continuous chain of evolution — the culmination of a series whose first term was the amoeba and penultimate the ape.
Today, however, man seems to consider himself not as the furthest degree in a continuous series, but rather as different in kind than the animal — as though man and animal evolve in parallel but decidedly separate series. The question of animal rights seems to refer less to the creatures' anteriority to humans in a single series than to the notion that in their own series they're reaching a level of humanity: Bambi, not a relative or ancestor of man's, but a deer that talks and thinks. It does not belong to our series, but resides at a comparable state of evolution in its own. Animals used to have a use value — meat, fur, ivory, plow the field and carry the soldiers — but now, when shrink-wrapping displays the meat but obscures its origin, every animal is essentially the pet. We are not to exploit these peers of ours, but to coexist with them. After all, did not such eminent researchers as John Lilly discover that dolphins and other animals have communicative abilities? The criteria of Descartes wouldn't even differentiate us anymore.
Nevertheless, while animals may develop "human" characteristics in their own evolutionary series, we nevertheless maintain a thorough-going separation with them in reality. In the aftermath of World War II, few would argue for the benefits of racial purity, and yet there is a tacit species purity affirmed in the horror of bestiality, half-breeds, and baby monsters. However much we indulge our zoophilia in fawning over cats and dogs (pet snakes, ant farms, goldfish...), sexual contact remains "the vice of the clodhopper" and "the sexual perversion of dull, insensitive, and unfastidious persons," as even Havelock Ellis terms it. It would seem that any sort of coupling betwixt human and inhuman were taboo — if it weren't for the sexual allure of the machine. So frequent in contemporary culture are instances where man-machine interface takes the form of intercourse that a pseudo-Borges would be necessary to catalogue them all: A Manual of Fantastic Mechanophilia. From the simple battery-operated dildo to the porno bbs, this is nothing if not a machine sex age.
In this light, perhaps bestiality really is reactionary, out-of-date, old-hat. Both In the Old Fashioned Way and Cultural Gothic, with their motorized humping, literally reduce animal sex to its mechanical simulation, as if to point up the fact that the forward march of technology has advanced over even the most bestial of activities. This is especially ironic given that contemporary technology has enabled scientists to produce any number of biological "monsters" or half-breeds by means of genetic manipulation. Experiments in this realm have already sown the seeds for entirely new industries such as "pharming," in which livestock are endowed with human genes in order to produce commercial drugs that can be extracted from their blood or milk. What is this if not another kind — alongside the love of pets — of non-erotic bestiality? The taboo against zoophilia is simply not a proscription against the production of hybrids or monsters: in the early part of the century experiments in enhancing men's virility by giving them transplants of animal sex characteristics (see Serge Voronoff's Testicular Grafting from Ape to Man, 1933) even resulted in a surgical vogue until, a few years later, the unhappy participants discovered the concept of organ-donor incompatibility.
The taboo against zoophilia thus does not genuinely concern itself with what animal sex can produce, but with its inability to reproduce. Traditional proscriptions against most forms of sex derive from the fear of wasting seed, and bestial couplings are necessarily sterile: not only, contrary to myth, does nature furnish a number of biological mechanisms which prevent foreign sperms from fertilizing native eggs, but oftentimes the animal is used in ways that don't even make cross-breeding a threat. It has been said that bestiality should even be called interspecific rape, since the animals rarely initiate contact. The goat in Cultural Gothic tolerates without soliciting the encounter, while the zebra in In the Old Fashioned Way could possibly be the aggressor, although the woman's hold on the legs of the zebra imply her complicity (and of course the original pornographic drawing was probably made by a man, who portrayed her with this complicity). If man expresses the animal in himself in fucking — Wilhelm Reich justly says that when a man orgasms, he's a jellyfish, when he represses himself, a worm — he expresses the man in himself by choosing or forcing himself on a creature of another species.2 This is a true rarity in the animal kingdom: Reich also mentions that it is not reason or language, in his view, but sadism that "is the only important trait differentiating man's structure from that of the animal."3 Perhaps we used to deny this sadism by imputing use value to the animal, as though it asked for everything we did to it. But today, if animals no longer seem to have innate use value, machines still do, and this may be why mechanophilia is less disturbing than bestiality: you never have to get consent from a machine.
Animal sex is probably second only to religion as a well-spring for images in the history of art.4 Though in practice proscribed by laws extending further back than the Bible, in art bestiality seems less taboo than regular old coitus: Leda and the Swan, Beauty and the Beast, the Rape of Ganymede, Pasiphae, the Minotaur, Centaurs raping women, Satyrs "surprising" nymphs, Zeus disguising himself as a bull to rape Demeter and Europa, as a serpent to seduce Persephone, as an eagle for Aegina, a pigeon for Pythia, a stallion for Dia — these themes may be largely mythological, but they certainly are not confined to Greek vases or Renaissance paintings. Cézanne, for instance, painted a fine version of the Leda story, and Picasso's self-identification with the Minotaur resulted in countless pictures of bulls copulating with women. In contrast, the works by Collishaw and McCarthy differ from this long tradition in that they do not seize upon mythological pretexts for depicting bestiality: they no longer clothe animal sex in myths, but rather cloak machines in animal sex. If McCarthy's sculpture suggests that the pleasures of bestiality will be lost unless transmitted from father to son, it is only because in the future sex may well be highly mechanical.
1. Havelock Ellis, Studies in the Psychology of Sex, Vol. III (NY: Random House, 1936), p79.
2. "In the animal, man, there still functions a worm.... One still frequently meets the concept that man–in spite of his development from phylogenetically older forms–represents a living being of a new kind, without connection with the forms from which he stems. In the segments of the spine and ganglia, the segmental character, and with that, the worm character of the biological system is clearly expressed." Or again: "the expressive movements in the orgasm reflex are functionally identical with those of a living and swimming jellyfish." Wilhelm Reich, Character Analysis (NY: Orgone Institute Press, 1949), pp395-6.
3. Wilhelm Reich, The Mass Psychology of Fascism (NY: Farrar, Straus & Giroux, 1970), p344.
4. For an exhaustive catalogue of art historical images, as well as literary excerpts, myths, court reports, and so on, see Roland Villeneuve, Le Musée de la bestialité (Paris: Henri Veyrier, 1973). |
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Kelly Formula: Money Management Key for Traders
Peter Bernstein
What do money management and data transmission over phone lines have in common? Uncertainty.
Problems associated with data transmission are very similar to issues a gambler or trader faces in determining the optimal amount of money to trade at any given time. Believe it or not, the concept of how much money you must trade is related to work of Bell engineers going back decades. In 1956 J. L. Kelly published a paper while working at Bell Labs. The paper sought to solve issues associated with noise over phone lines, noise that was random and very unpredictable.
We found an excerpt from Kelly, J. L., Jr., titled “A New Interpretation of Information Rate”, taken out of the July, 1956 edition of Bell System Technical Journal:
If a gambler places bets on the input symbol to a communication channel and bets his money in the same proportion each time a particular symbol is received, his capital will grow (or shrink) exponentially. If the odds are consistent with the probabilities of occurrence of the transmitted symbols (i.e., equal to their reciprocals), the maximum value of this exponential rate of growth will be equal to the rate of transmission of information. If the odds are not fair, i.e., not consistent with the transmitted symbol probabilities but consistent with some other set of probabilities, the maximum exponential rate of growth will be larger than it would have been with no channel by an amount equal to the rate of transmission of information.
The formula has come to be simply known as the Kelly formula and it was great inspiration to great trend traders and systems traders. They were inspired directly by Bell Labs research to develop systems centered around determining the optimal bet size (otherwise known as money management).
Kelly Formula
A web post from one of our readers gave a great description:
What is the Kelly criterion (or formula)? It is a formula for calculating how much to bet. It assumes that your objective is long term capital growth (getting rich). The handicapper’s choice of money management strategy is similar to the stock market choice between growth stocks and income stocks. Growth stocks tend to be more volatile, but in the long term return more profit. That is because the profits from growth stocks are reinvested rather than skimmed off. Every reinvestment is a calculated risk. Therefore, income stocks tend to fluctuate in value less, but also return less profit in the long term. Kelly betting is for growth. It reinvests profits, and thus puts them at risk. If your objective is to make small but consistent profits,it may be too aggressive a money management scheme.
The Kelly’s formula is : Kelly % = W – (1-W)/R where:
• Kelly % = percentage of capital to be put into a single trade.
• W = Historical winning percentage of a trading system.
• R = Historical Average Win/Loss ratio.
Edward O. Thorp: Beat the Dealer
Thorp is famous for his blackjack paperback, Beat the Dealer, where he explores Kelly for gambling.
The central problem for gamblers is to find positive expectation bets. But the gambler also needs to know how to manage his money, i.e. how much to bet. In the stock market (more inclusively, the securities markets) the problem is similar but more complex. The gambler, who is now an investor, looks for excess risk adjusted return. In both these settings, we explore the use of the Kelly criterion, which is to maximize the expected value of the logarithm of wealth (maximize expected logarithmic utility).
Thorp continues:
The criterion is known to economists and financial theorists by names such as the geometric mean maximizing portfolio strategy, maximizing logarithmic utility, the growth-optimal strategy, the capital growth criterion, etc.
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One Dimensional Motion
Time and Distance
By one dimension we mean that the body is moving only in one plane and in a straight line. Like if we roll a marble on a flat table, and if we roll it in a straight line (not easy!), then it would be undergoing one-dimensional motion. There are four variables which put together in an equation can describe this motion. These are Initial Velocity (u); Final Velocity (v), Acceleration (a), Distance Traveled (s) and Time elapsed (t). The equations which tell us the relationship between these variables are as given below.
v = u + at
v 2 = u 2 + 2as Physics Calculator click for calculator
s = ut + 1/2 at 2
Two and Three Dimensional Motion
Scalar or Vector?
To explain the difference we use two words: 'magnitude' and 'direction'. By magnitude we mean how much of the quantity is there. By direction we mean is this quantity having a direction which defines it. Physical quantities which are completely specified by just giving out there magnitude are known as scalars. Examples of scalar quantities are distance, mass, speed, volume, density, temperature etc. Other physical quantities cannot be defined by just their magnitude. To define them completely we must also specify their direction. Examples of these are velocity, displacement, acceleration, force, torque, momentum etc.
Parallelogram law of vector addition
If we were to represent two vectors magnitude and direction by two adjacent sides of a parallelogram. The resultant can then be represented in magnitude and direction by the diagonal. This diagonal is the one which passes through the point of intersection of these two sides.
Resolution of a Vector
It is often necessary to split a vector into its components. Splitting of a vector into its components is called resolution of the vector. The original vector is the resultant of these components. When the components of a vector are at right angle to each other they are called the rectangular components of a vector.
Rectangular Components of a Vector
As the rectangular components of a vector are perpendicular to each other, we can do mathematics on them. This allows us to solve many real life problems. After all the best thing about physics is that it can be used to solve real world problems.
Note: We will show all vector quantities in bold. For example A will be scalar quantity and A will be a vector quantity.
Let A x and A y be the rectangular components of a vector A
A = A x + A y this means that vector A is the resultant of vectors A x and A y
A is the magnitude of vector A and similarly A x and A y are the magnitudes of vectors A x and A y
As we are dealing with rectangular components which are at right angles to each other. We can say that:
A = (A x + A y) 1/2
Similarly the angle Q which the vector A makes with the horizontal direction will be
Q = tan -1 (A y / A x)
Laws of Motion
Newton's laws of motion
Through Newton's second law, which states: The acceleration of a body is directly proportional to the net unbalanced force and inversely proportional to the body's mass, a relationship is established between
Force (F), Mass (m) and acceleration (a). This is of course a wonderful relation and of immense usefulness.
F = m x a Physics Calculator click for calculator
Knowing any two of the quantities automatically gives you the third !!
Momentum (p) is the quantity of motion in a body. A heavy body moving at a fast velocity is difficult to stop. A light body at a slow speed, on the other hand can be stopped easily. So momentum has to do with both mass and velocity.
p = mv Physics Calculator click for calculator
Often physics problems deal with momentum before and after a collision. In such cases the total momentum of the bodies before collision is taken as equal to the total momentum of the bodies after collision. That is to say: momentum is conserved.
This is the change in the momentum of a body caused over a very short time. Let m be the mass and v and u the final and initial velocities of a body.
Impulse = Ft = mv - mu Physics Calculator click for calculator
Work, Energy and Power
Work and energy
As we know from the law of conservation of energy: energy is always conserved.
Work is the product of force and the distance over which it moves. Imagine you are pushing a heavy box across the room. The further you move the more work you do! If W is work, F the force and x the distance then.
W = Fx
Energy comes in many shapes. The ones we see over here are kinetic energy (KE) and potential energy (PE)
Transitional KE = ½ mv 2
Rotational KE = ½ Iw 2
here I is the moment of inertia of the object (a simple manner in which one can understand moment of inertia is to consider it to be similar to mass in transitional KE) and w is angular velocity
Gravitational PE = mgh Physics Calculator click for calculator
where h is the height of the object
Elastic PE = ½ k L 2
where k is the spring constant ( it gives how much a spring will stretch for a unit force) and L is the length by which the spring is stretched or compressed form the equilibrium position.
Power (P) is work( W) done in unit time (t).
P = W/t
as work and energy (E) are same it follows power is also energy consumed or generated per unit time.
P = E/t
In measuring power Horsepower is a unit which is in common use. However in physics we use Watt. So the first thing to do in solving any problem related to power is to convert horsepower to Watts. 1 horsepower (hp) = 746 Watts
Circular Motion
Circular Force
In the diagram v is the tangential velocity of the object. a is the centripetal (acting towards the center of the circle) acceleration and F is the centripetal force. r is the radius of the circle and m is mass of the object.
a = v 2 / r
F = ma = mv 2/r
Kepler's Laws
Towards the end of the sixteenth century, Tycho Brahe collected a huge amount of data giving precise measurements of the position of planets. Johannes Kepler, after a detailed analysis of the measurements announced three laws in 1619.
1. The orbit of each planet is an ellipse which has the Sun at one of its foci.
2. Each planet moves in such a way that the (imaginary) line joining it to the Sun sweeps out equal areas in equal times.
3. The squares of the periods of revolution of the planets about the Sun are proportional to the cubes of their mean distances from it.
Newton's law of universal gravitation
About fifty years after Kepler announced the laws now named after him, Isaac Newton showed that every particle in the Universe attracts every other with a force which is proportional to the products of their masses and inversely proportional to the square of their separation.
If F is the force due to gravity, g the acceleration due to gravity, G the Universal Gravitational Constant (6.67x10-11 N.m2/kg2), m the mass and r the distance between two objects. Then
F = G m 1 m 2 / r 2
Acceleration due to gravity outside the Earth
Here let r represent the radius of the point inside the earth. The formula for finding out the acceleration due to gravity at this point becomes:
g' = ( r / re )g
In both the above formulas, as expected, g' becomes equal to g when r = re.
Properties of Matter
The mass of a substance contained in unit volume is its density (D).
D = m/V
Measuring of densities of substances is easier if we compare them with the density of some other substance of know density. Water is used for this purpose. The ratio of the density of the substance to that of water is called the pecific Gravity (SG)S of the substance.
SG = D substance / D water
The density of water is 1000 kg/m 3
Pressure (P) is Force (F) per unit area (A)
P = F/A
Specific Heat
You may have noticed that metals, for example copper, heat faster than water. You would require 4186 J of heat to raise the temperature of water by 1 degree Celsius. On the other hand 1 kg of copper would zoom to this temperature after it receives only 387 J of heat. It is known that every substance has a unique value of amount of heat required to change the temperature of 1 kg of it by 1 degree Celsius. This number is referred to as the specific heat of the substance. Let Q be the heat transferred to m kg of a substance, thereby changing its temperature by dT. The specific heat c of the substance is defined as
c = Q/mdt
Juggle the expression, and we get the heat transferred from a body to its surroundings or the other way around. This is given by.
Q = m c dT
For example the heat required to increase the temperature of half a kg of water by 3 degrees Celsius can be determined using this formula. Here m, mass of water is 0.5 kg and the dt, the temperature rise = 3 deg C and we know the specific heat of water is 4186 J/kg. So here the heat required will be
Q = 0.5 x 4186 x 3 =6280 J
It is as simple as that !!
he table below gives the specific heat of some common substances
J/kg. o C cal/g. o C
Aluminium 900 0.215
Copper 387 0.0924
Glass 837 0.200
Gold 129 0.0308
Ice 2090 0.500
Iron 448 0.107
Silver 234 0.056
Steam 2010 0.480
Water 4186 1.00
According to Ohm's Law electric potential difference(V) is directly proportional to the product of the current(I) times the resistance(R).
V = I R
The relationship between power (P) and current and voltage is
P = I V
Using the equations above we can also write
P = V 2 / R
P = I 2 R
Resistance of Resistors in Series
The equivalent resistance (R eq) of a set of; resistors connected in series is
R eq = R 1 + R 2 + R 3 + - - -
Resistance of Resistors in Parallel
The equivalent resistance (R eq) of a set of resistors connected in parallel is
1/R eq = 1/R 1 + 1/R 2 + 1/R 3 + - - -
© Tutor 4 Physics
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Anamim meaning
Source: http://www.abarim-publications.com/Meaning/Anamim.html
🔼The name Anamim in the Bible
The Anamim are descendants of Mizraim, who was a son of Ham, who was a son of Noah (Genesis 10:13).
🔼Etymology and meaning of the name Anamim
The name Anamim looks like it comes from the rich root group ענה (ana):
However, there no certainty whether the name Anamim was actually derived from this root group. It its signature abrupt style, BDB Theological Dictionary deems the 'form dubious and locality unknown,' and hints no further to any meaning
According to Jones' Dictionary of Old Testament Proper Names, the ana-part of the name Anamim is derived from the first group of meanings, ענה (ana I), meaning to answer, respond, testify. The mim-part is identical to מים (mayim) meaning waters:
And thus, Jones' Dictionary of Old Testament Proper Names translates this name as Responding Waters.
It should be noted that the extension ים is a common indication of plural (much like the English -s), which leads to the possibility that our word Anamim is in fact the plural of ענם. That word does not occur in the Bible except as an (assumed) text error: the city Anem (1 Chronicles 6:73), meaning Double Fountain. This would give to Anamim the meaning Clusters of Double Fountains, which is a bit excessive. |
What Do Graduate Schools Want?
FRBSF: Economic Letter - Unemployment and Productivity (10/12/2001)
Sounds like there are no grand theories on connections between unemployment and productivity (at least in the long run).
The article states 2 ways in which technology improvements can cause permanent changes to the natural unemployment rate:
1. Job search technology speeds up the process of finding the right employer for the unemployed worker. The natural unemployment rate is 'natural' because all workers spend some time in between jobs. If this in-between time is shorter than fewer people will be unemployed at any one time.
2. Productivity growth increases profit (more output per unit of labor) which encourages firms to want to produce more by hiring more workers.
There's one 'it depends' model presented that shows that examines the fact that some technical progress may destroy more jobs than it creates. The determining factor is the cost of upgrading jobs as capital becomes obsolete. If it costs a lot to upgrade an existing job as the capital used in that job becomes obsolete, that job will be abandoned. The problem with this model is that the relationship between unemployment and productivity depends on the type of job and the technology. In other words, it says nothing of the relationship between the two in aggregate.
Too bad, this last model has appeal. I wonder if we can talk about productivity in terms of its relationship to unemployment by examine its decreasing and increasing components... change in employment equals change in leveraged productivity (technical progress that improves existing jobs) minus change in replicative productivity (technical progress that replaces existing jobs). How would you measure aggregate productivity broken into its leveraged and replicative components? I'm sure I could find out more here, but I'm going to pass on paying $30 to see the article... Berkeley has it, and I guess you can access the article via ScienceDirect if your inside Berkeley's network.
Web Allows People Like You
And Me to Spot Trends. Uh-Oh.
"But I have grander ambitions for the software. I foresee a day when everyone online will be linked into one big collaboratively filtered network, instantly knowing what everyone else with the same sensibilities is thinking and doing."
I wonder what this 'trend' does for the definition of "pop culture"...
The Wedge Between Output and Employment Growth: Archive Entry From Brad DeLong's Webjournal
Seem's pretty straight forward. The economy grows because of productivity improvements. Each worker can produce more stuff. Also, if the unemployment rate goes up, the economy shrinks. Less workers to produce the stuff. So employment and productivity are substitutes for each other.
Well, today we have a situation were productivity and the economy are rising but unemployment is rising, too. This is easy to explain by saying that income gains from productivity increases are outstripping the income losses from unemployment.
Question: is there a causal relationship between productivity and unemployment or are they really perfect substitutes? I mean, is there some future economy that has such high productivity that it only takes one worker to produce all the output. Two follow-ups: First, what happens if productivity goes to infinity? No workers required and 100% unemployment? Second, is it 'bad' for productivity to replace employment?
Thomas Sowell: Who's Rich
Sowell points out that there is often confusion between wealth and income. He claims that rich people may have insignificant income as its their wealth that makes them rich. He would have you conclude that discussions about taxing the rich are misplaced because rich people are wealthy and don't necessarily have high incomes. Futhermore, when you 'unfairly' tax high income earners, you're punishing folks that are making high contributions to the economy. You punish those folks, you punish the economy. Which means you punish us all.
I suppose this is correct in terms of income derived from labor, but what about investment income... I agree that there should be low(ish) taxes on income derived from labor, but this is not an argument for low taxes on investment income or on wealth in general.
It doesn't seem fair to tax income based on work performed. A virtuous tax policy would have low tax on income from salary. It does seem just to tax wealth and income derived from wealth.
Books to Study Before Going to Graduate School in Economics
Ok, I'm not real sure why I didn't look at about.com before...
Letters of Rec for old farts like me (I'm 5 years out of school)
Yeah, I've been looking for an answer to this question!
I wonder if its possible for me to get research experience?
Three Pillars of Learning
- Depth; What ideas are important?
- Breadth; What connections are there between ideas?
- Process; How do people think about things? Models.
These pillars work with each other in a virtuous cycle of learning. Models of how the world works help you to understand it. Those models help to build deep understanding of a particular idea. The deep understanding means that you understand the model further, you generalize and then apply the model to other areas or fields. Because no model is perfect in a more general setting, applying the model more generally forces you to reevaluate the model and improve it or scrape it. The outcome is a better model and the cycle continues.
Graduate school is a social environment that allows this cycle to continue unhindered.
Questions To Ask When Thinking About Pursuing a PhD
"Research shows that up to half of the students who begin doctoral study never receive the Ph.D. One culprit in attrition is a poor match. Doctoral study may be a poor choice in the first place, or there may be a poor fit between the student and the program."
Questions that need an answer:
1. Why a PhD?
2. Why economics?
3. Why Berkeley?
4. What advisors at Berkeley? Why?
EconLog, High income and Wealth: Library of Economics and Liberty
I like this one... I'll come back to it. Basically, what would be a just distribution of wealth? What would a virtuous distribution look like? Assume each, justice and virtue, are mutually exclusive (I'm not sure if that's the right term... in other words, justice plus virture adds up to 100% of your morals, I guess). Square the virtuous and just models of wealth distribution with their respective importance.
Also, I want to look into the 'Survey of Consumer Finances' more... For my personal financial planning if nothing else...
Len Burman et al. on the Alternative Minimum Tax
Interesting the politics of tax policy. You hear raise taxes, lower taxes, but in reality revenue needs to be had and services need to be paid for (especially new, expense entitlement programs, cough cough perscription drugs). This article talks about the AMT. If the politicians do nothing, more and more folks will be subject to the alternate tax and the politicians, in effect, have raised taxes and nobody can hold them responsible.
Another example is the hullabaloo regarding expensing stock options. Stock gains (aka capital gains) are taxed at a famous maximum of 15%. Income is taxed upwards of 35%. Assume the policy change encourages companies to switch from stock options to straight salary compensation and you're talking a 20% tax increase on the margin!
Even better, wages are subject to workers comp whereas stock option compensation is not.
In any case, they've risen taxes with impunity. What a deal!
War Overview
Good one!
Mr. Clueless reviews the arguements for war. His presentation seems a bit like post-rationalization, but its also probable that such a case would not have enjoyed so much political success... Side note: its strange that an argument made before a war is so much different then a case after and that these differences seem politically necessary. Point being: we would not have been able to go to war under the auspices of 'rearchitecting the middle east'. It took the 'they are going to kill us with bad weapons' argument to get folks behind the war.
In the Bush adminstration and the larger neocon movement, am I witness to great leadership or to a Machevellian political agenda to rule the world? The answer seems to depend on my mood more than the arguments one side or another makes! Most likely, this is due to the fact that both sides are right.
Tony Blair for President
Tony Blair's speech to Congress
Blair for President! Seriously though, are there any cogent counterarguments to the points Blair articulated so well in his speech to Congress last week?
A quick review:
- terrorism is bred of poverty and illiberity
- terrorism plus destructive technology is a security threat to ALL the west
- the best way to combate terrorism is to spread liberty
- we mustn't let terrorists get their hands on WMD
- the only way to prevent terrorist from getting WMD and to spread liberty are to be sure the world is in lock-step with us
Is there another way to look at the state of the world? If not, are the only arguments remaining to do with HOW to implement the last point?
Mankiw vs. Greenspan?
Mankiw is saying that growth, spurred by the administration's tax policy, will increase the government's top line and reduce the deficit. Greenspan is saying that deficit's are bad when the economy is at full employment. It's not clear that these two men would disagree with each other. What counterposes their opinions?
The only difference seems to be the writers' editorial bent.
Movie review: Flash Dance
Alex is a welder by day and she is a exotic dancer at night. As the movie opens, we come to understand that her dream is to become a classical dancer. As a kid, her Nana took her to ballet and her father taught her to see the music at classical music concerts. Now she is grown up and in a fork in the road of her life. Does she realize her dream or does she accept her position in life?
The film is filled with characters that have had their dreams crushed or have not realized their dream. Hanna wanted to be an ice skater, but that dream was crushed by one poor performance. Do you really only have one shot? Richy wants to be a stand-up comic, but will he realize his dream? He's failed once before will he try again? Johnny never even had a dream.
Sometimes family or friends will get in the way. Their own crushed dreams will make them uninspiring, even without words. The blow can come in the form of a rolling of the eyes or just plain disinterest. Sometimes their own failures will cause them to conspire to make sure you don't reach your dream. They might actively try to dissuade you to give up your dream. Some will want to see you put in your place (your place, of course, is no where near your dream). If you don't resist their calls to remain were you are, then you will. What would have happened if Alex didn't make Johnny let go of her in that alley?
In the end, the worst enemy of your realization of your dream is you. You'll be afraid to bring your dream into focus and you won't know what to strive for. Or you'll know your dream, but you'll be afraid to go after it. The hardest part will be to take the first step: to fill out the application, to lift the first weight, to take the test or to write the first line. Why did Alex leave the line to fill out the application to the ballet school? Seeing others fail before her needn't have stopped her from taking that first step.
Some never take that first step and their dream fades away. Tina, another dancer at the club, doesn't know why she didn't grow beyond the night club. You could ask "why does this happen? Why do people lose sight of their dreams?" But the answer doesn't matter. The most academic explanations involving Tina's psychology or descriptions of her upbringing, will not change the fact that she never realized her dream. What really matters is that you don't lose sight of your dreams.
Alex got some help, a "kick in the ass", by Nick. He is her self-made, successful boss and owner of the steal factory. He has realized his dream and now he wants to see her realize hers. He nudged her into finally applying to the ballet school. Of course, luck plays its part and Nick, who happens to know the music conservatory director, makes a few phone calls to get her an audition.
The story in Flashdance is, at the same time, timeless and dated. Discovering and realizing your dreams is a classic story. For Alex, she was from humble beginnings and she had to break free from the boundaries of poverty. Her's is the classic story of the American dream. Despite economic adversity, she worked hard and was passionate. She has no agenda and she pursued her passion for its own sake. With a little luck and determination, she made it to the audition.
Today, the story of the American dream has to be modified. Most people grow up with out the economic hardship that Alex had. For the average kid, everything is handed to them. They don't have to struggle find the open door, many doors are open for them at birth. It's easy to realize your dream, when you don't have to strive for it, right?
Can the American dream be salvaged with such a lack of struggle?
Your dream, the American dream, is what defines your purpose in life. To have purpose is a struggle for everyone not just those in poverty. Where poverty denies you options, privilege saturates you with them. In poverty, the path you choose defines you. In privilege, you have to choose among your many options and you're defined by what you chose and what you didn't chose. In both poverty and privilege, your path is not set but it will appear to be. And in both you have to overcome the temptation to accept your standing in life and to discover your true ambition. From there, whatever your challenge, you need focus to become great.
Whether your obstacle is poverty, privilege or something else: "Take a deep breath and jump". After that first step, what if you don't make it? You will, I know you will.
Lyrics to the What a feeling.
A seemingly objective and well thought out article by a member of congress(!). Neo-conservatives have taken over the government (congress and the executive). They believe in Machiavellian philosophy of authoritarian government, perpetual war and "honorable" lies.
The congressman argues that neo-conservative actions are eroding the constitution and the principles of the Founders when they 'entangle' us in foreign affairs and support the welfare state. The first point is better made, it seems probable that the current foreign policy of the US government is contrary to our neutral/isolationist tradition. While the declaration of independence proclaimed universal, inalienable rights of all humans, the subsequent constitution never required us to spread these ideals overseas. In our tradition, foreign policy is only made in respect to our defense. Of the two options for defense strategy, altruistic neutrality or proactive meddling (including preemptive war), I think the constitution, and certainly the founders, would favor the former. In any case, it wouldn't hurt for someone to remake the argument for neutrality. (My first reaction to this idea is negative as I think 'isolationism'... How can you square neo-liberal ideas of free trade and the American tradition of neutrality? Both seem to be sane ideas, more sane than pre-emptive war.)
The second point is not as effectively made. Why does big government undermine the constitution? My gut agrees with this assertion, but the proper argument wasn't made in the article.
In any case, I want to revisit this article and the "liberty committee".
Coldplay Lyrics: A Warning Sign
A warning sign
I missed the good part then I realised
I started looking and the bubble burst
I started looking for excuses
Come on in
I've got to tell you what a state I'm in
I've got to tell you in my loudest tones
That I started looking for a warning sign
When the truth is
I miss you
Yeah the truth is
That I miss you so.
A warning sign
You came back to haunt me and I realised
That you were an island and I passed you by
When you were an island to discover
Come on in
I've got to tell you what a state I'm in
I've got to tell you in my loudest tones
That I started looking for a warning sign
When the truth is
I miss you
Yeah the truth is
That I miss you so
And I'm tired
I should not have let you go
So I crawl back into your open arms
Yes I crawl back into your open arms
And I crawl back into your open arms
Yes I crawl back into your open arms
Coldplay Lyrics: The Scientist
The Scientist
Come up to meet you, tell you I'm sorry
You don't know how lovely you are
I had to find you
Tell you I need you
Tell you I set you apart
Tell me your secrets
And ask me your questions
Oh let's go back to the start
Running in circles
Coming up tails
Heads on a silence apart
Nobody said it was easy
It's such a shame for us to part
Nobody said it was easy
No one ever said it would be this hard
Oh take me back to the start
I was just guessing
At numbers and figures
Pulling your puzzles apart
Questions of science
Science and progress
Do not speak as loud as my heart
Tell me you love me
Come back and haunt me
Oh and I rush to the start
Running in circles
Chasing our tails
Coming back as we are
Nobody said it was easy
Oh it's such a shame for us to part
Nobody said it was easy
No one ever said it would be so hard
I'm going back to the start
Randy E. Barnett on Supreme Court & Sodomy on National Review Online
Randy's right on. He says we're all missing the boat on the Supreme Court sodomy case. The real story is that the burden of proof regarding whether or not a law governing private affairs is constititional has moved from the individual to the government. The court used to presume that laws passed by the Congress or by State legislatures were constitutional. You had to petition the court to prove that the law was not constituional. Now, the court will require the government to justify its limits on liberty.
My favorite line is this one: a legistlatures "judgment of immorality means nothing more than that a majority of the legislature disapproves of this conduct, which would be true whenever a legislature decides to outlaw something. Such a doctrine would amount to granting an unlimited police power to state legislatures."
Americans must preserve institution of marriage
Is it just me or does this editorial have no substance at all? To summarize: gay marriage is coming, marriage is important for society because you raise children through this institution, marriage is being destroyed because people are confused about what it is, society is headed to ruins. Oh and how dare those unelected charlatans (i.e. the nine Supreme Court justices) destroy our society without asking us?
If marriage is so damned important, why would making more people eligible to participate in the institution be a bad thing? Also, why, again, can't homos raise children?
What confuses me about marriage is that there are these arbitrary rules governing the institution. Marriage is only betwen men and woman. (Why?) Marraige is important to help raise kids. (What about couples that don't have kids?) The institution of Marraige must be supported by the government but that support must be unequal. (What other legal institution have this kind of baised governmental support?)
Policy should not be guided by personal preference. Senator Santorum should express his opinion, but he shouldn't insist that his preferences for how other people live be codified in the constitution.
Marriage 'tames' geniuses, criminals
Hah! I knew it...
Previously, I've heard that criminal 'instincts' are dulled by marriage. This is why marriage a stabilizing force in society and why societies that have strong institutions of marriage have 'evolved' to be less violent. The context being that American culture is headed to shit because of the decline of marriage.
This article goes one step further. Marriage dulls creativity. So to counter the conservative argument that marriage is good for society, this article suggests that it can be bad by distracting our best creative minds.
Put up or shut up
It's time that I put my words into actions. Repeatedly, I've said to myself and others that its more important to pursue your own ends, to be an individual first. I've said that the groups you belong to come second to yourself. Remarkably, its much easier to say then do.
I'm a tall, white man. I'm a geek. I'm college educated and I'm a manager at work. I'm the Man. I'm a member of KQED (the SF public TV station), the EFF, the ACLU, and I'm registered in the green party. I'm a member of the NRA, but I don't tote a gun. I don't smoke and I'm a jogger. I'm a genXer and a child of young boomers. And until a few weeks ago, I was one half of a 'couple'.
Each of those groups wants to grab a hold of my identity. The green party pamphlets, printed on triple recycled paper, come in the mail with my renewal notices from all the charity 'membership' organizations. My intercourses with them entice me with offers of money, pride and a sense of belonging. They shame me into their arms with sprinkles of white liberal guilt and suggestions of bad things to come without my support. I'm reminded how I should or should not live. Slight gestures dictate how I should or should not behave. Examples show me how I should or should not think.
I'm seduced into consuming this group fodder and the blame for this should is placed squarely on my own willingness to belong. That willingness is guided by insecurity and lack of confidence in myself. For wanting to belong is the opposite of being an individual. It takes courage to be an individual and you have to work at it. Lack of courage or laziness pushes you away from yourself and it becomes easier to consume others' thoughts and behaviors then it is to invent your own.
But individuality is insidiousness as it is its aim to undermine others' individuality. To have a thousand followers, is to be the ultimate individual. For to have followers means that you've created thoughts or movements that are so original and provocative that others give up their own to borrow yours. You must destroy others' individuality to complete your own.
On the flip side of the coin: as an individual who seeks to be creative, you're drawn to other individuals who are like-minded. Like gravity in the forming of solar systems, these individuals form groups. And of course, those groups, being groups, are hell bent on destroying the individuals in them.
Why do individuals gravitate towards each other? You cannot create anything out of a vacuum. An individual's creativity, whether its in art or science, is shaped by the observations made around them and it is shaped by the creations that came before. In painting for example, the artist fills his canvas with particular visualizations of the natural world. To be original and therefore creative, he must paint in response to others that have painted before him. Even if he paints the opposite of what has been painted before, he can only paint in the context of what was painted before or what is being painted now. In any case, the very notion that he is a painter requires that he has joined that group of people that wield paintbrushes and who know the names of all the colors on the color wheel. There's no such thing as the painter who is not a painter.
If you are an individual consumed with ideas, you are naturally attracted to other people that are consumed by similar ideas. Ideas, like works of art, build off each other. The group's purpose becomes allowing the individuals to efficiently build off each others ideas. The group develops short hand ways to talk about things, making it easier to create new ideas and subsequently attracting more people to the group. This is why economists talk of demand curves and sociologist talk of power dynamics. In physics, relativity was a revolutionary idea, but, contrary to some theories of otherworldly origins of Einstein, even it was developed in the context of the thinking on physics of the day. Who could really believe in the "ether", anyway?
In a sense, this all means that groups enable individuals to be creative. By presenting a dogma, the group allows individuals to build upon the faith or to bounce ideas off the canon. An individual's creation can be additive or it can be made in contrast to the present way of looking at things.
So groups are good, right? Right, except they also can be destructive to the individual. The group has the 'average' individual. Of course, the 'average' group member is not a real person, but if you took an individual out of the group, at random, you would find some of the traits of the 'average' individual. The larger the group gets, the easier it is for any one lazy individual in the group to pretend to be average. So instead of generating their own thoughts and actions, the lazy group members starts acting and thinking like the 'average' group member.
Well, I've been getting lazy lately. I was too willing to let my identity morph into the averages of the two primary groups I belonged to. First, I'm a manager at a small company. My thoughts were consumed by 401ks, stock options and all manners of business jargon and fad-speak. This is all typical of your average businessperson. Second, I got lazy in relation to my 'couple' group status. Buying a house and having children consumed my thoughts. Again, these things are typical of your average middle class male provider.
Truth be told, I'm not really big on making a lot of money or on deriving meaning in life via reproduction. My laziness and group identities were pulling me away from myself.
I'm resolved now to do the following because they better define me and speak to what I think is important in life:
- I will volunteer in the community, ideally helping children or the poor (within the month)
- I will meet interesting people that are interested in ideas and learning (ongoing)
- I will recruit and groom a replacement at work (starting in October)
- I will get into a top economics PhD program in a California public school (2005-2009)
- three letters of recommendation (1 by the end of the year, the other two before next summer)
- I will take math and economics-related courses at DeAnza (one each quarter)
- I will take the GRE (early next year)
I will make progress towards these goals every day. I'll note progress on this website. Please, loyal readers, keep me in check.
Web www.ambrosini.us
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A Man Of Conscience
Nothing is more central to the American experience than the journey of the immigrant from the Old World to the New in search of freedom, security of person, or simply his daily bread. If Carl Schurz, who arrived from Germany in 1852, found all these things in abundance, he repaid the republic in rare and precious coin: half a century of honest, devoted service. He was a crusader for abolition, a brave (if unlucky) general in the fight to save the Union, a vigorously independent United States senator, and an outstanding Cabinet officer. What doubled and trebled the value of that service was that it came at a time when probity and dedication were sorely needed, when in public life the weak and the wicked had all but pre-empted the field. As writer, editor, and lecturer, Schurz was a never-tiring advocate of reform; from the Civil War to the turn of the century he was, says his biographer, Claude M. Fuess, “the … exceedingly useful incarnation of our national conscience.”
Few foreigners have reached these shores with a more romantic past. Carl Schurz (he pronounced it Shoortz ) was a “forty-eighter,” one of that small band of German intellectuals who in 1848 risked all in an attempt to bring unity and a measure of democracy to the Fatherland. A schoolmaster’s son from tiny Liblar, near Cologne, Schurz was a nineteen-year-old student at Bonn when, one morning late in February of that revolutionary year, a comrade rushed into his attic room with word that the French had driven Louis Philippe from his throne and proclaimed a republic. Discontent had been brewing in Germany for some years, and now, all over the country—and particularly in the university towns—the exciting news from Paris sent crowds boiling into the streets to listen to fiery speeches. Their leaders drafted petitions to the land’s most powerful ruler, the autocratic Frederick William IV of Prussia, demanding that he take steps to unite into one great empire Germany’s congeries of kingdoms, grand duchies, margraviates, bishoprics, and principalities, and that he convene a national parliament that would significantly broaden the people’s civil and political rights.
For a time it seemed that the uprising had succeeded: the parliament was duly called, and at Berlin Frederick William made a great show of adopting democratic ways. But the parliament frittered away its time in debating, when its only chance for life lay in bold, decisive action; Frederick, unable or unwilling to assert his leadership over a united Germany, prorogued the parliament and called out troops to suppress the revolution.
It crumpled quickly, for reasons which Carl Schurz’s own experiences make clear. With a band of over one hundred men under a former lieutenant of artillery, he set out to capture an armory across the Rhine from Bonn. Schurz carried out his assignment, which was to commandeer a ferry to get the revolutionists across the river. But he neglected to put the ferry out of action once it had served their purpose; the boatman, whether out of royalist sympathies or simply because he was a businessman with his eye on the main chance, promptly recrossed to Bonn and brought over a body of Frederick William’s dragoons. Hearing the trumpets and hoofbeats of his pursuers, the timid artillery lieutenant ordered his band to disperse. Schurz and his companions watched, humiliated, as thirty horsemen —hardly a third of their own numbers—swept on unmolested toward the armory. The whole thing had the flavor of opéra bouffe: a good plot for Sigmund Romberg, perhaps (steins lifted, voices raised in song), but hardly a blueprint for empire. Schurz himself, captured and imprisoned by the Emperor’s forces, managed a midnight escape through a storm sewer and eventually made his way to Switzerland.
His cloak-and-dagger exploits were not over. His intellectual and revolutionary mentor, Professor Johann Gottfried Kinkel, was confined in Berlin’s Spandau prison. Kinkel’s wife had succeeded in raising money for his release, and now sent word to Schurz in Switzerland asking him to slip back into Germany to organize and carry out the rescue. It was a fantastic plot, complete with bogus passports, “magic ink,” a bribed jailer, relays of horses and closed carriages to carry Kinkel and his liberator north to the Baltic, and a schooner to take them from there to England. It was fantastic, but it worked: on a Sunday morning in November, 1850, the Little Anna dropped anchor at Leith, Scotland, and Kinkel and Schurz went ashore to freedom. It had been a really remarkable exploit for a youngster of twenty-one; its echoes quickly found their way to the United States, where, magnified by distance and time, they would make Schurz famous among German-Americans and pave the way for his subsequent political success among them. |
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In 1940, 268 people named Benon were living in the United States. In a snapshot:
• On average men worked 42 hours a week
• 33% were children
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• 88 were children
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• Most immigrants originated from Denmark
• Most mothers originated from South Carolina
• They most commonly lived in Michigan
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• 28% reported their race as other than white
• 8 women had paying jobs
• 69%, or 29 people, lived in homes they rented
• The typical household was 3 people
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• Most fathers originated from New Mexico |
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• The youngest was 2 and the oldest was 73
• They typically took 18 weeks of vacation a year
• 3 owned their homes, valued on average at $883
• Most common occupation was laborer
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• 11 migrated within the United States from 1935 to 1940
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• 23 were first-generation Americans
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• They most commonly lived in Ohio
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Singing Advice
You Could Drive a Truck Through It
You Could Drive a Truck Through It
Vibrato can be one of the great mysteries of singing. We all recognize the beauty and energy it brings to the voice, but many singers struggle with how to create, control, or, when stylistically appropriate, even it. Nashville-based voice coach Brett Manning is one of the most recognized names in vocal instruction. He is the author of the "Singing Success" home study program, and his client list includes Keith Urban and Taylor Swift. Manning has also created the only CD instruction course dealing solely with vibrato.
Defining Vibrato
One of the first steps in unlocking the mystery of vibrato is defining it. Manning sees the science of vibrato in everyday occurrences, such as a flag blowing in the wind. "Atmospheric pressure is 14.6 pounds per square inch, so if you blow across a surface, like a flag, it's going to suck that thing upwards," he says. "When I blow across my vocal cords, there should be this puff of wind that is created by natural oscillation."
Manning further defines vibrato as changes in pitch and compression, although not necessarily limited to one or the other. "You can have a combination of both, or less or more of the other," he says. Manning believes it's important to keep the balance between them finely tuned. "If I have a vibrato that is just compression, I may be panting to get a vibrato but staying on the same pitch," he says. "If I have a vibrato that is just an oscillation in pitch, I may tend to wobble."
Why It's Important
Manning believes there are three major benefits to having a well-developed vibrato. "It beautifies tone, it frees up muscular tension, and it soothes the ear," he says. This last point is an important one for the listener. "The oscillation in sound creates an oscillation in vibration against the cilia, the hairlike particles that measure sound in our ear," he explains. Manning says the changing of pitch creates relaxation for the listener, whereas straight tones can create tension in the ear: "If one plays a straight tone on the violin, after a while the ears go crazy; they beg to hear the vibrato. It's because the ears can only take one solid pitch for so long."
Developing It
Helping a singer develop a natural vibrato is something Manning specializes in. He has created a whole series of exercises, available on CD and in his private sessions, that lead a singer step by step to this balance. These exercises include moving back and forth quickly on different intervals, all the way up to an octave, in order to increase the agility of the voice and get the vibrato started. Eventually, Manning says, the vibrato will occur naturally: "I do believe vibrato is allowed more than it is made, but initially it's made so that later on it's allowed."
Manning also uses vocal licks and trills to help speed up a vibrato. "If your vibrato is slow, then your licks will be slow," he says. "If it's fast, your licks will be fast. Doing a fast trill will help your vibrato speed up, and doing fast vibrato will help your trills speed up."
Decreasing It
Sometimes a singer will have too much vibrato—a vibrato that's slow and with too great a change in pitch. This is often referred to as a "wobble." Manning is able to help this condition by connecting the coordination of natural speech to singing. "I had a woman in her 60s with a terrible wobble," he says. "She told me, 'I can't help it. Every time I sing this happens.' I told her, 'Yes, you can help it. You've been singing the whole time you've been talking to me.' "
Manning used the lack of wobble in her speaking voice to establish a new balance in her singing: "I had her say 'Wow' and then to start holding out the word longer and longer." He then took her through different pitches and scales on this spoken word, slowly allowing the vibrato to return. "Soon she was able to sing with a wonderful vibrato," he says. This all springs from Manning's fundamental idea of the voice: "Whenever we make tone, we are singing."
Removing It
There are times when a singer will want to have no vibrato, as this can be very effective in certain styles of music. "One of the beauties of vibrato is when you don't use it," Manning says. However, this can be as difficult for some singers as finding vibrato is for others. Manning again uses the natural speaking voice to help guide the singer. "You give consent every time you use vibrato," he says. "When people say, 'I always have vibrato,' I say, 'No way. Not unless you have it in your speaking voice and you have a medical condition.' "
It becomes a very simple application for Manning. "Everybody's already singing without vibrato when they talk," he says. "I just have them hold a pitch and not think singing."
Can Everyone Get It?
Now matter how difficult vibrato may be initially for the singer, Manning has never had an instance when a singer failed to develop it. "Not everyone got a great vibrato," he says, "but everyone got enough where it defined them. Vibrato does help define your sound."
Brett Manning and his vibrato course can be found at
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Canid hybrid
Genetic considerations
Many members of the dog family can interbreed to produce fertile offspring.
Molecular analysis indicates 4 divisions of canids:
1. Wolf-like canids including the domestic dog, gray wolves, coyotes, and jackals
2. The South American canids
3. Old and New World red-foxlike canids, for example, red foxes and kit foxes
4. Monotypic species, for example, bat-eared fox and raccoon dog
The wolf (including the dingo and domestic dog), coyote, and jackal, all have 78 chromosomes arranged in 39 pairs. This allows them to hybridise freely (barring size or behavioural constraints) and produce fertile offspring. The wolf, coyote, and golden jackal diverged around 3 to 4 million years ago. Other members of the dog family diverged 7 to 10 million years ago and are less closely related and cannot hybridise with the wolf-like canids: the yellow Jackal has 74 chromosomes, the red fox has 38 chromosomes, the raccoon dog has 42 chromosomes, and the Fennec fox has 64 chromosomes. Although the African Wild Dog has 78 chromosomes, it is considered distinct enough to be placed in its own genus.
Legal implications of hybrids
Dog hybrids kept as pets are prohibited in certain jurisdictions, or are classed as wild animals and must be housed in the same way as purebred wolves. For example, hybrids of the domestic dog with the wolf, coyote, dingo, jackal, fox, dhole, African Wild Dog, or Raccoon dog are prohibited in the State of Hawaii.
Wolf-dog hybrid
Main article: Wolf-dog hybrid
The domestic dog (Canis lupus familiaris) is now regarded as a domesticated form of the Grey Wolf (Canis lupus lupus), and therefore belongs to the same species as other wolves such as the Dingo (Canis lupus dingo). Therefore hybridization between these sub-species is unremarkable.
People wanting to improve domestic dogs or create an exotic pet have sometimes bred them back to wolves. Grey wolves have been crossed with wolf-like dogs such as German Shepherd Dogs, Siberian Huskies, and Alaskan Malamutes. The breeding of wolf-dog hybrids is controversial, with opponents purporting that it produces an animal unfit as a domestic pet. There are a number of established wolfdog breeds in development. The initial hybrid offspring are generally back-crossed to domestic dogs to maintain a domestic temperament and consistent conformation. First-cross wolf-dog hybrids are popular in the USA, but retain many wolf-like traits.
Dingo hybrids
The Australian Dingo(Canis lupus dingo) breeds freely with domestic dogs. This is now so widespread that many dingoes are now mongrels. Some dingo hybrids have been deliberately bred as pets, but are turned loose due to behavioural problems. These hybrids are accepted back into the wild dingo population where they breed with pure dingoes. In some parts of Australia, up to 80% of dingoes are hybrids. Dingoes are distinguishable from domestic dogs through DNA and through having longer teeth and longer muzzles.
The Australian Kelpie sheepdog is widely believed to be a hybrid of dingo and north England collie dogs, but this (the dingo blood) is not upheld by breed documentation. The Australian Cattle Dog breed is known to have been influenced by the dingo.
According to the partwork "Animal Life and the World of Nature" (Vol 1, 1902-1903), Lord Walter Rothschild owned a dingo-wolf hybrid bred by Mr and Mrs HC Brooke from a tame male dingo and a semi-tame female wolf.
Dog-fox hybrids
An unconfirmed female terrier/fox hybrid was reported, and later euthanized (killed), in the UK. British gamekeeper folklore claims that terrier bitches can produce offspring with male foxes. Other dog breeds claimed to have hybridized with foxes are the Alaskan Malamute, Sheltie, Siberian husky, and most of the hound groups. The supposed hybrids (known as a dox) are likely to be natural variation in the domestic dog.
There has been a reported cross between a domestic dog and a South American fox, but the fox was a fox-like wolf, known as the maned wolf, and not a true fox.
In Saskatchewan, Canada there was another supposed dox, this time a female miniature Sheltie with a wild fox. There was a litter of three, but only one survived. The surviving (a female) was barren, and looked like an almost pure fox, with slight variations. However, the variability of dogs in appearance makes it impossible to determine whether an animal is hybrid based on looks. In most cases the dox will have gold or yellow eyes, wired hair, and with black red and gray hairs covering most of the body.
Coyote hybrids
Main article: Coydog
Coydogs (male coyote/female dog) Coydogs were once believed to be present in large numbers in Pennsylvania due to a declining coyote population and a burgeoning domestic dog population. Most supposed hybrids were naturally occurring red or blond color variations of the Coyote or were feral dogs. The breeding cycles of dogs and coyotes are not synchronized and this makes interbreeding uncommon. If interbreeding had been common, each successive generation of the coyote population would have acquired more and more doglike traits.
Coyotes are solitary by nature; this trait is carried across to coyote-dog hybrids. This can result in problematical and unsociable behaviour which makes them generally unsuitable as pets. As a result, they may be abandoned or allowed to stray and be absorbed into the feral dog or coyote population. However if the coyote (or dogote) is found at a very young age and raised properly they can, in fact, become a pet much like some wolf-dogs are kept. Much time and effort must be put into them for this to occur.
The mating of a male dog and a female coyote results in a dogote. There has been one report of a dogote which arose from a male German shepherd/female coyote mating in the wild. Hybrid pups were found after a female coyote was shot. The adult dogotes resembled German shepherds in color.
The dogote displays unsociable behavior much like the coydog but through much time and effort can, like the coydog, become a pet.
Coyote-Dingo hybrid
Coyotes have also been crossed with Australian dingoes in zoological gardens.
Coyote-wolf hybrid
Coy-wolves (Coyote/Wolf) have occurred in captivity or, rarely, in the wild where the choice of same-species mates has been limited. Coyote/Red Wolf hybrids have been found. Some consider that the American Red Wolf is not a true species because it can hybridize with both the Grey Wolf and the Coyote; however, it is now known that hybridization between species (in general) happens more often than previously thought. Some consider it a Grey Wolf/Coyote hybrid and use this argument to prevent conservation of the Red Wolf. Some hybridization occurred when pure Red Wolves were in decline and interbred with the more numerous Coyotes. The species boundary is often preserved by geographic or behavioural separation, not by genetic separation.
Jackal hybrids
The Wolf and Jackal can interbreed and produce fertile hybrid offspring, which are sometimes known as huskals. Coyote/Jackal Hybrids have also been bred as pets by Wolf-dog enthusiasts. Dogs have been crossed with golden jackals; however, they cannot produce fertile offspring with yellow jackals as the latter have only 74 chromosomes compared to 78 in the dog. It is also thought that Pharoanic Egyptians crossbred domestic dogs with jackals, producing a jackal-dog that resembled the god Anubis.
(Note: Wild horses have 66 chromosomes.[citation needed] Domestic horses have 64.[citation needed] Wild horses and domestic horses can interbreed and produce fertile hybrids. The reason golden jackals differ in chromosome number is most likely because golden jackals have 2 pairs of chromosomes that are twice as long but contain similar gene content as 4 pairs of dog chromosomes. This might reduce fertility but it would not likely completely sterilize golden jackal-dog hybrids.)[citation needed]
In The Variation Of Animals And Plants Under Domestication Charles Darwin wrote:
Several years ago I saw confined in the Zoological Gardens of London a female hybrid from an English dog and jackal, which even in this the first generation was so sterile that, as I was assured by her keeper, she did not fully exhibit her proper periods; but this case was certainly exceptional, as numerous instances have occurred of fertile hybrids from these two animals.
In Russia, Golden Jackal/Lapponian Herder hybrids were bred as sniffer dogs because Jackals have a superior sense of smell and Lapponian Herders are good cold climate dogs. Also Fox Terrier, Lunehund, and Spitz blood were bred for over generations and for almost 25 years have been dedicated to the forming and presice genes of the Sulimov dogs. As well as a superior sense of smell, important at low temperatures where substances are less volatile and therefore less pungent, Sulimov Dogs are small sized and can work in confined spaces. When tired, their normally curled tails droop, making it clear to the handler that the dog needs to be rested.
The jackal hybrids were bred by senior researcher Klim Sulimov, Senior Research Assistant at the D.S. Likhachev Scientific Research Institute for Cultural Heritage and Environmental Protection in Russia.
Male Jackal pups had to be fostered on a Husky bitch in order to imprint the Jackals on dogs. Female Jackals accepted male Huskies more easily. The half-bred Jackal-Dogs were hard to train and were bred back to Huskies to produce quarter-bred hybrids (quadroons). These hybrids were small, agile, trainable and had excellent noses. They are called Sulimov Dogs after their creator and may one day be registered as a working breed of dog. Twenty-five jackal-dog hybrids are used by Aeroflot at Sheremetyevo Airport in Moscow, for functions which include bomb-sniffing. Their breeding program dates back to 1975, but was not applied to bomb detection until 2002.
Canid interfertility chart
Tentative synoptic table
Parents Result Possible?
Wolf - Dog Wolfdog yes
Wolf - Dingo yes
Wolf - Coyote Red wolf yes
Wolf - Jackal Jackal hybrids yes
Wolf - Fox no
Dog - Dingo Dingo hybrids yes
Dog - Coyote Coy-dog and dogote yes
Dog - Jackal Jackal hybrids yes
Dog - Fox Dox no
Coyote - Dingo Coy-dingo yes
Coyote - Jackal yes
Coyote - Fox no
Dingo - Jackal yes
Dingo - Fox no
Others: Dhole, Eastern Canadian Wolf, Lycaon, Pariah dog, Pseudalopex, Red Wolf
References and external links
• Wolf Dog resources
• Wolf dogs
• Hybrid Dingoes
• BBC News: Sulimov Dogs
• Moscow News: Sulimov Dogs
• Dogotes and Coydogs
• Coydogs
• WolfSource
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Canid_hybrid". A list of authors is available in Wikipedia. |
HDMI Cable Information Center
Ever since HDMI inputs and outputs started to show up on consumer audio and video devices, we have been asked question after question about HDMI. Is it really better than analog video? Do I need it, and when and why? What sorts of distance limits apply to HDMI cable runs, and what kind of cable do I need?
A simple "FAQ" doesn't really suffice to answer these questions, because some of the answers turn out to be surprisingly complex. Meanwhile, we have our own Belden-built HDMI products, which have some unique attributes that are themselves somewhat complex to really describe and explain. Rather than try to load all of this up onto one impossibly-long web page, we have condensed these issues into a number of different subject areas, and tried to treat each of them in a way which will do the complexity of the subject justice, while avoiding confusion and EE jargon wherever possible. In preparing these articles, we've tried hard to neither oversimplify nor to overcomplicate the subjects, and to keep our language as straight-forward, plain and Anglo-Saxon as can be; we hope that you find them enjoyable and understandable.
There is one question we receive more than any other, though, which we feel we should probably answer right here. We're often asked whether, if one is just running a short (say, 6 foot) length of HDMI cable from one device to another, without switches, couplers, relays and whatnot, there will be any quality upgrade in sound or picture from buying a higher-quality HDMI cable, or whether one should just go with something reasonably-made and economical. The answer is that, at short lengths, in the vast majority of circumstances, all non-defective HDMI cables will perform equally well (and no, it doesn't matter what spec version it is); the signal is digital and the devices don't know whether they're hooked up with a four-dollar cable or something better or pricier. We spend a lot of time in these articles addressing the problems with HDMI, and in particular the problem of getting consistent performance at high resolutions over long distances, because many of our customers have installations that present that type of challenge. In those applications, cable quality can be a critical part of making your system perform well, and it's for that reason that we are proud to offer our Belden Bonded-Pair HDMI cables which represent the very best in HDMI cable quality. But in the digital world, sometimes the best value for your money is the very best product on the market, and sometimes it's the lowest-priced product on the market. For those latter cases, we offer some of the best HDMI cable pricing you will see anywhere, on our Tartan Cable line of HDMI products.
"Premium HDMI Cable" -- What is it, and Why?An explanation of HDMI Licensing's newest cable certification tier.
HDMI Cables -- An OverviewAnswers a variety of common questions about HDMI cables, and addresses various misconceptions surrounding HDMI.
HDMI 2.0 Compliance and CablesIs this cable 2.0 compliant? The answer is surprisingly simple.
Is This Cable HDMI 1.4-compliant?Explains why it's incorrect to refer to an HDMI cable as a "1.4 cable" and how the 1.4 and other HDMI spec versions actually relate to cable capabilities.
What do these HDMI Spec Versions (1.3, etc.) Mean?Tries to clear the confusion over the various versions of the HDMI spec, as related to cable construction and electrical properties.
Where Does HDMI Cable Come From?If it's not ours, it comes entirely from China; this article explains and details the point, and provides resources to see for yourself where an HDMI cable is made.
How Long Can HDMI Run? Addresses limitations on distance with HDMI connections.
What's the Matter with HDMI?Explains how the HDMI standard was badly designed, the problems that result, and what one can do to avoid difficulties.
What's a "Certified" HDMI Cable?Addresses the myth of "1080p Certification" and the question of just what sort of testing HDMI cables are actually subjected to.
Belden HDMI CablesA detailed explanation of the rationale behind the design of our Belden bonded-pair HDMI cables, and how that design relates to performance.
HDMI versus Component--Which is Better?Explains the difference between HDMI and component video cable connections, and generally why they may behave differently from one another.
Component to HDMI CablesIf you think "there aren't any," you're right. Here's why.
Other Articles and Resources:
The articles above are all specifically related to HDMI cables; but there are a lot of general electrical principles which are as applicable to HDMI as to other types of cabling, and we have treated those in our Articles area. These include such things as the significance of wire gage, the use of exotic materials in cable construction, the characteristics of different shielding types, the whole question of characteristic impedance, and so on. We have tried to address each of these subjects in a way that's helpful in understanding cable behavior and in choosing cable for an application, again with no more complicated language than is really necessary to get the point across.
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A small downland village, Clayton lies astride an old Roman road. The little Saxon church of St John the Baptist boasts some very early wall paintings, which are probably the work of monks from St Pancras Priory at Lewes. The paintings have been variously dated from 1080 to 1140, making them some of the earliest surviving examples in England.
The paintings above the chancel arch are particularly rich and ornate. Two historic mills dominate the skyline above Clayton. These two mills are generally referred to as Jack and Jill. Jack, the larger, was built as a tower mill about 1866. It is now a private residence. Jill, a post mill, is smaller than Jack, but older, built about 1821 at Brighton. It was later moved to Clayton, and is now open to visitors, who can watch corn being freshly ground.
Near Clayton is a historic railroad tunnel, one of the largest built during the 1840s railroad boom in Victorian Britain. Above one end of the tunnel is Tunnel House, a mock Tudor dwelling built as a residence for the tunnel keeper. |
An angler in Lake Woodlands recently found a vegetarian cousin of the piranha on his hook, state wildlife officials have confirmed.
Following a report from Houston ABC affiliate KTRK, Brannon Meinkowsky, a state game warden whose beat includes Montgomery County, said the fisherman had likely caught a fish known as a pacu. Fishers at Lake Conroe have encountered it as well, Meinkowsky says.
"Pacu is in the piranha family, but it's more of a vegetarian eater," Meinkowsky says. "Probably what happened is that it was in somebody's aquarium, and the fish got too big, and rather than kill it they thought it would be a good idea to let the fish go in the lake."
That's illegal, he adds, but he says it's likely that this is a fish that was released by its owner, not one that was actually hatched in the lake. Unless more of the pop up, he says, there's no way of knowing how many pacu are in the lake or whether or not they are breeding. Luckily, Meinkowsky says he's seen no evidence of breeding yet.
Plant-eating fish, like the non-native tilapia that have been introduced to Lake Conroe, can affect the ecosystems of those lakes, but Meinkowsky says he's still more worried about carnivorous invasive species, like the snakehead.
"While it's disappointing that these pacu are in the lake, it could be a lot worse," he says.
Anyone who catches one of these fish in Lake Woodlands is advised to reach state wildlife authorities so that they can keep records on the species. |
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357 Cards in this Set
• Front
• Back
CN X innervates what muscles
All muscles with the work "palat" except tensor veli palitini (CN V3)
Lip testing
CN VII, mi-mi-mi
6th aortic arch becomes
Proximal part of pulmonary arteries
CN XII function
tongue movements
Location for lumbar puncture
iliac crest (between L3 - L5)
Fetal milestone within week 10
Genitalia have male/female characteristics
Bell's palsy
Peripheral ipsilateral facial paralysis
Part of cochlea that picks up low-frequency sounds
the apex
Function of supraoptic nucleus
Thist and water balance
Location of Brunner's glands
submucosa of duodenum
Drug used to keep PDA open
ACE inhibitor teratogenicity
Renal damage
Signs of CN XII lesion
Tongue deviates toward side of lesion
Anterior cruciate ligaments attaches where
Anterior tibial attachment
What has a fenestrated barrel hoop basement membrane
the sinusoids of the spleen
Nerves passing through internal auditory meatus
Foramen ovale becomes
Fossa ovalis
Brunner's glands function
secrete alkaline mucus
Branchial pouch 3 develops into
inferior parathyroids (dorsal wings) and thymus (vental wings) (3rd pouch = 3 items (thymus + 2 parathyroids)
Direct hernia location
Hesselbach's triangle (medial to inferior epigastric artery)
Esophagus and vagus cross diaphgram at what level
Brachial plexus injury leading to decreased thumb function (Pope's blessing)
Median nerve of lateral/medial cords
Neuroectoderm becomes
neurohypophysis, CNS neuron, oligodendrocytes, astrocytes, pineal gland
Fetal milestone within week 2
Bilaminar disk, 2 cavities (yolk & amniotic), 2 components to placenta (cytotrophoblast/synctiotrophoblast) (Rule of 2's)
Zona adherens components
E-cadherin and actin filaments
Limbic system functions
Feeding, Fighting, Feeling, Flight, Fornication (5 F's)
Femoral triangle contents
femoral vein, artery, and nerve
In the womb monozygotic twins have
2 amniotic sacs and either 1 or 2 chorions and placentas
1st aortic arch becomes
Maxillary artery (1st is MAX)
Thenar muscles function
Opponens pollicis, Abductor pollicis, Flexor pollicis (OAF)
Branchial arch 1 derivatives
Mandible, Malleus, incus, sphenoMandibular ligament, Muscle of Mastication, Mylohyoid, anterior belly of digastric, tensor tympani, tensor veli palatini
Lesion of optic tract causes
contralateral homonymous hemianopsia
low neck dermatome
Most common tumor of the adrenal medulla in children
Oligohydraminos cause
bilateral renal agenesis (Potter's)
Sudden jerky, purposeless movements
Surface ectoderm becomes
adenohypophysis, lens of eye, epithelial linings, epidermis
Function of ventral posterior nucelus, lateral part (VPL)
body senses (proprioception, pressure, pain, touch, vibration)
Male homologue of glans clitoris
glans penis
Endolymph made by
stria vascularis
Ulnar nerve deficit sensory findings
Medial palm and ulnar 1.5 fingers
Polyhydraminos cause
esophageal/duodenal atreasia
3rd aortic arch comes
Common Carotid (C=3rd letter of alphabet)
skull cap dermatome
Ulnar nerve deficit motor findings
Wrist flexion and adduction, impaired adduction of thumb and ulnar 2 fingers, intrinsic hand muscles (claw hand)
Abnormal opening of penis on dorsal side
Hippocampus projects to
Subiculum (projecting to mamillary nuclei), Septal area
distal 1/3 of transverse colon to upper portion of rectum
Umbilical artery contents
de-oxygenated blood from iliac vessels
Umbilical cord contents
2 umbilical arteries, 1 umbilical vein, allantoic duct, Wharton's jelly
Passage for CN I
cribiform plate
Nucleus solitarius receives what
visceral sensory information (e.g., taste, gut distention, etc.) (CN X)
Ulnar nerve injury location
Medial epicondyle
CN III function
occulomotor, pupil constriction, accommodation, eyelid opening
Branchial arch 3 nerve
IX (innervates 1 muscle and nothing else --> stylopharyngeus)
Peripheral nerve layers
Epineurium, perineurium, Endoneurium
CN VII function
facial movement, anterio 2/3 taste, lacrimation, salivation (submaxiallry and submandibular glands)
EPO secreting cells of kidney
juxtoglomerular cells
Left horn of sinus venosus gives rise to
coronary sinus
5th aortic arch becomes
stroke of anterior circle of Willis signs
general sensory and motor dysfunction, aphasia
Allontois becomes
Urachus or median umbilical ligament (not medial)
Cleft palate mechanism
Failure or fusion of lateral palatine, nasal septum, and/or palatine process
Function of anterior hypothalamus
Regulates cooling (Anterior Cooling = A/C)
Branchial cleft 1 derivative
external auditory meatus
Male homologue of vestibular bulbs
corpus spongiosum
Spermatid acrosome derived from
Golgi apparatus
Hindgut blood supply
inferior mesenteric
what channel has round pores (100-200 nm in diameter) with no basement membrane
the sinusoids of the liver
Macula adherens components
keratin and desmoplakin
Location for pudendal nerve block
ischial spine
Notochord function
Induces ectoderm to for neuroectoderm
Function of ventral posterior nucleus, medial part (VPM)
facial sensation including pain
Midgut blood supply
superior mesenteric
Sperm development
spermatogonium (diploid 2N), primary spermatocyte (diploid 4N), secondary speramatocyte (haploid 2N), spermatid (haploid N)
Most common tumor of the adrenal medulla in adults
Broad ligament of uterus contents
round ligaments of the uterus and ovaries and the uterine tubules and vesels
Abberant development of 3rd and 4th branchal pouches leads to
DiGeorge syndrome --> T cell deficiency
Hypoglossus innervates what
All muscles with the word "glossus" in them, except for palatoglossus (X)
Macula adherens
desmosome made up of keratin and desmoplakin
Spermatid flagellum derived from
Branchial arch 2 nerve
Function of ventral anterior/lateral (VA/VL) nuclei
Sudden wild flailing of one arm
Consequence of lesion in arcuate fasiculus
Conduction aphasia; poor repitition with good comprehension; fluent speech
secretory product of Zona glomerulosa
Regulatory control of zona glomerulosa
Branchial clefts derived from
Ectoderm (CAP = from outside to inside Ecto/Meso/Endo=Clefts/Arches/Pouches
CN I function
stroke of posterior circle of Willis signs
cranial nerve deficits (vertigo, visual deficits), coma, cerebellar deficits (ataxia)
Brachial plexus injury leading to deltoid paralysis
Axillary nerve of posterior cord
Gamma loop
CNS stimulates gamma-motor neuron --> contracts intrafusal fiber --> increased sensitivity of reflex arc
Paramesonephric duct develops into
Fallopian tube, uterus, part of vagina
Found within the red pulp of spleen
T cells
Branchial arch 6 derivatives
all intrinsic muscles of the larynx except one: cricothyroid
Ligaments of the uterus
Suspensory ligament, Transverse cervical, Round ligament, Broad ligament
Ductus arteriousus becomes
ligamentum arteriosum
Function of oligodendroglia
central myelin production
Path for pupillary light reflex (light in right eye)
CN II --> right lateral geniculate -> right pretectal nucleus --> bilateral Edinger-Westphal nuclei --> CN III --> ciliary ganglion --> pupil contraction
Neural crest cells become
ANS, dorsal root ganglia, melanocytes, chromaffin cells, pia mater, celiac ganglion, Schwann cells, ondontoblasts, parafollicular (C) cells of thyroid, laryngeal cartilage
connects cells to underlying extracellular matrix
Branchial arch 2 derivatives
Stapes, Styloid process, lesser horn of hyoid, Stylohyoid, muscles of facial expression, Stapedius, Stylohyoid, posterior belly of digastric
Palate elevation testing
CN X, kuh-kuh-kuh
Consequence of lesion in subthalamic nucleus
One consequence of enlarged left atrium
Slow writhing movements of fingers
CN V function
mastication, facial sensation, tensor veli palatini, tensor tympani
nipple dermatome
Brachial plexus injury leading to claw hand
Lower Trunk (C8/T1)
Consequence of lesion in basal ganglia
tremor at rest (athetosis)
Spermatid neck contains
Retroperitoneal structures
Duodenum (2nd-4th parts), Ascending & Descending colon, Kidney/ureters, Pancreas (except tail), Aorta, IVC, Adrenal glands, Rectum
Lesion in Wednig-Hoffman disease
LMN --> flaccid paralysis
umbilicus dermatome
Muscle that opens mouth
Lateral pterygoid (Lateral Lowers the jaw)
Fasciculus gracilis location
Medial dorsal column
Dorsal motor nucleus sends what
Autonomic (parasympathetic) fibers of X to heart, lungs, and upper GI
Cells that activate B cells in Peyer's patches
M cells
4th Branchial arch nerve
X (like 6; 6+4 = X)
Branchial arches dervied from
Fasciculus cuneatus
Vibration/join position of arms
Right lymphatic duct drains what
right arm and right half of head
Radial nerve deficit motor findings
lack of triceps & brachioradialis reflex, loss of extensor carpi radialis longus (wrist drop)
Lesion in poliomyelitis
LMN --> flaccid paralysis
Lumbar puncture layers
Skin, Fascia, Ligaments (supraspinous, interspinous, flavum), Epidural space, Dura mater, Subdural space, Arachnoid, Subarachnoid space (CSF)
I-cell disease
Failure of addition of mannose-6-phosphate --> lysosome proteins secreted outside of cell instead of into lysosome
Contralateral weakness of lower face only
UMN lesion
Function of Schwann cells
peripheral myelin production
Hypothenar muscle functions
Op[onens digiti minimi, Abductor digiti minimi, Flexor digiti minimi (OAF)
Uncal herniation signs
Ipsilateral mydriasis (stretching of CN III), contralateral homonymous hemianopsia (compression of ipsilateral posteroir cerebral arery), Ipsilateral paresis (compression of contralateral crus cerebri, duret hemorrhages (caudal displacement of brain stem)
secretory product of adrenal medulla
Catecholines (80% epi, 20% norepi)
Muscles of mastication
Masseter, temporalis, medial pterygoid, lateral pterygoid
Consequence of lesion in cerebellar vermis
Truncal ataxia, dysarthria
venous drainage below pectinate line
Incus and malleus derived from
1 branchial arch
Consequence of lesion in mamillary bodies
Wernicke-Korsakoff encephalopathy (confabulations, anterograde amnesia)
DES teratogenicity
Vaginal clear cell adenocarcinoma as an adult
Functions of Golgi apparatus
distributes proteins/lipids, modifies N-oligosaccharide on aspagine, adds O-oligosaccharides to serine and threonine, proteoglycan assembly, sulfation of sugars, addition of mannose-6-phosphate to lysosomal proteins
Passage for CN V2
foramen rotundum
beta cells of pancreatic islet produce
Fetal susceptibility to teratogens
3rd-8th weeks
alpha cells of pancreatic islet produce
Location of Peyer's patches
lamina propria and submucosa of small intestine
Rough endoplasmic reticulum function
site of synthesis of secretory proteins and N-linked oligosaccharide addition to many proteins
Indirect hernia location
Lateral to inferior epigastric artery
CN II function
Right ovary/testicle venous drainage
right gonadal vein --> IVC
Fetal milestone within week 4
Heart begins to beat
Endoderm becomes
Gut tube epithelium, lungs, liver, pancreas, thymus, thyroid, parathyroid
Consequence of lesion in frontal lobe
Release signs (personality changes, deficits in concentration, orientation, judgement)
Male homologue of labia majora
Consequence of lesion in broca's area
Expressive aphasia (BROken speech) with good comprehension
Unhappy triad of the knee
torn MCL, medial meniscus, and ACL
Nucleus ambiguous function
CN IX, X, XI (Motor only)
Branchial pouch 4 develops into
superior parathyroids
4th aortic arch becomes
Aortic arch on left; Subclavian artery on right
difference between primary and secondary lymph node follicles
primary are dense and dormant; secondary are pale and active
Median nerve injury location
Supracondyle of humerus
Zona occludens
tight junctions
Nucleus ambiguous sends what
Motor innervation of pharynx, larynx, upper esophagus (CN X)
Golgi tendon organ function
Ib fiber senses tension and provides inhibitory feedback to alpha-motor neuron
Loss of knee jerk
Femoral (L2-L4)
Kartagener's syndrome defect
Dynein arm defect --> immotile cilia
Cocaine teratogenicity
Abnormal development and addiction
Dorsal pancreatic bud becomes
Pancreatic body and tail
Lesion in ALS
combined UMN and LMN with no sensory deficit
Femoral triangle borders
Medial edge of Sartorius, Inferior edge of inguinal ligament, Lateral border of adductor longus
delta cells of pancreatic islet produce
Most common location of coronary artery occlusion
CN IX function
Posterior 1/3 taste, swallowing (stylopharyngeus), salivation (parotid), monitoring carotid body/sinus
Sperm food supply
Vision defect with left parietal lesion
right lower quandrantic anopsia
Passage for CN V3
foramen ovale
Most common location of circle of Willis aneurysm
Anterior comminicating artery
Direct hernia usual age
Older men
Nerves passing through jugular foramen
Drug used to close a patent PDA
Zona adherens
intermediate junction
Nerves passing through foramen magnun
Median nerve deficit sensory findings
Loss over lateral palm, thumb, and radial 2.5 fingers
GI blood supply
Foregut (stomach--duodenum, liver, gallbladder, pancreas)-Celiac; Midgut (duodenum to transverse colon)-SMA; Hindgut (tranverse colon to upper colon)-IMA
2nd aortic arch becomes
Stapedial artery and proximal part of carotid artery (Second=Stapedial)
inguinal ligament dermatome
Suspensory ligament of uterus contents
ovarian vessels
Fasciculus gracilis
Vibration/joint position of legs
Branchial arch 1 nerve
Tongue taste innervation
CN VII, IX, X (solitary nucleus)
Function of lateral hypothalamic nucleus
Digestive tract layers
Epithelium, Lamina propria, Muscularis mucosa, Submucosa (Meissner/Submucosal plexus), Muscularis propria (inner circular muscle, Auerbach'/Myenteric plexus, outer longitudinal muscle)
Branchial arch 6 nerve
X (like 4, 6+4 = X)
Type III collagen
reticulin - skin, blood vessels, uterus, fetal tissue, granulation tissue
Reflex arc
muscle stretch --> intrafusal stretch --> Ia afferent stimulation --> alpha-motor neuron stimulation --> reflexal extrafusal contraction
Left recurrent laryngeal wraps where
arch of the aorta
Most common locatio nfor vertebral disk herniation
between L5 and S1
Brachial plexus injury leading to Saturday night palsy
Radial nerve of posterior cord
Potter's syndrome
Bilateral renal agenesis
duodenum to poximal 2/3 of transverse colon
Innervation above pectinate line
Middle cerebral artery supplies
lateral aspect of brain, Broca's and Wernicke's speech areas
Brachial plexus injury leading to difficulty flexing elbow
Musculocutaneous nerve of lateral cord
Consequence of lesion in right parietal lobe
Spatial neglect
Sign of unilateral lesion of cerebellum
Patient falls toward the lesion
CN VIII function
hearing and balance
Function of microglia
Myenteric (Auerbach's) plexus function
coordinates motility via parasympathetic effector neurons between muscle layers
Contents of cavernous sinus
Internal carotid artery, CN III, IV, V1, V2, VI, postganglionic sympathetic fibers en route to the orbit
CN VI function
abducts eye with lateral rectus (abducens)
Mesoderm becomes
Dura mater, muscle, bone, cardiovascular/lymphatic system, blood, uorgenital, serous linings, spleen, adrenal cortex
Muscles of larynx innervated by
Notochord becomes
nucleus pulposus of the intervertebral disk
Lateral striate arteries supply
internal capsule, caudate, putamen, globus pallidus
Brachial plexus injury leading to wrist drop
Posterior cord (C7)
kneecap dermatome
Foregut blood supply
Passage for CN II
optic canal
Meckel's diverticilum from
persistance of vitelline duct or yolk stalk
Function of hypothalamic setpate nucleus
Sexual urges (Septate=Sex)
Indirect hernia usual age
INdirect = INfants
Number of spinal nerves
31 pairs (8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal)
Branchial arch 3 derivatives
Greater horn of hyoid, stylopharyngeus
Nucleus solitarius
CN VII, IX, X (Sensory only)
Lower border of spinal cord in adults
Brachial plexus injury leading to claw hand
Ulnar nerve of medial cord
CN IV function
abducts, introverts, and depresses eye (superior oblique muscle)
Contents of paracortex of lymph node
T cells
Fetal milestones within weeks 3-8
Neural tube, heart beats, oragnogenesis, susceptible to teratogens
Nissl bodies location
rought ER of neurons; Not in axon or axon hillock
Upper and lower lesion paralysis with weakness of upper and lower face
LMN lesion
Egg development
Primary oocytes being meiosis I and arrested in prophase until ovulation; Meiosis II is arrested in Metaphase until fertilization
Borders of hesselbach's triangle
Inferio epigastric artery, lateral border of rectus abdominis, inuinal ligament
Brachial plexus injury leading to waiter's tip
Upper Trunk (C5/C6)
CN XI function
head turning, shoulder shrugging
Aorta, thoracic duct, and azygous cross diaphragm at what level
Function of ventromedial nucleus
Satiety (without ventromedial nucleus you'll grow ventrally and medially --> you'll get fat)
Vision defect with right optic radiation lesion
left hemianopsia with macular sparing
Common location of lumbar puncture
Between L3-L4 or L4-L5
Branchial arch 4 derivatives
thytoid/cricoid/arytenoids/corniculate/cuneiform cartilages, most pharyngeal constrictor muscles, cricothyroid, levator veli palatini
Spermatic cord layers
External spermatic fascia, cremasteric muscle and fascia, internal spermatic fascia
Male homologue of greater vestibular glands (of Bartholini)
Bulbourethral glands (Cowper)
secretory product of Zona reticularis
sex hormones
Function of lateral geniculate nucleus
visual (Lateral to Look)
Loss of dorsiflexion
Common peroneal nerve (L4-S2)
Thymus apperance
Dense cortex (immature), Pale medulla (mature), Hassall's corpuscles
Stapes derived from
2nd branchial arch
Diphragm derived from
Septum transversum, Pleuroperitoneal folds, Body wall, Dorsal mesentery of esophagus (Several Parts Build Diaphragm)
Nephrotic syndrome malfunction
loss of basement membrane charge
Male homologue of labia minora
ventral shaft of penis
Function of ependymal cells
Inner lining of ventricles
Structures perforating diaphragm and level
T8-IVC, T10-Esophagus/VaGus, T12-Aorta/thoracic duct/azygous vein (I 8 10 EGgs AT 12)
Consequence of lesion in Wernicke's area
Sensory (fluent/receptive) aphasia (Wernickes=Wordy) with poor comprehension
Sign of CN X lesion
uvula deviates away from lesion
Regulatory control of zona reticularis
juxtaglomerular apparatus function
secretes renin in response to decresased blood pressure, decreased Na+ delivery, or increased sympathetic tone
Fetal erythropoiesis
Yolk sac (week 3-8); Liver (week 6-30); Spleen (week 9-28); Bone marrow (week 28 onward) Young Liver Synthesizes Blood
Umbilican vein becomes
ligamentum teres hepatitis
Common teratogens
ACE inhibitors, cocaine, DES, Iodide, 12-cis-retinoic acid, thalidomide, warfarin, x-rays
islest are concentrated in what part of pancreas
Borders of hasselbach's triangle
Inferior epigastric artery, Lateral border of rectus abdominis, Iguinal ligament
What inhibits mullerian duct in males
Mullerian inhibiting substance secreted by testes
Radial nerve injury location
Shaft of humerus
Submucosal (Meissner's) plexus function
regulates secretions, blood flow, and absorption via parasympathetic terminal effector neurons between mucosa and inner layer of smooth muscle
Most abundant protein in the body
Transverse cervical ligament of uterus contents
uterine vessels
Fasciculus cuneatus location
Lateral dorsal column
SA and AV nodes blood supply
Fetal milestone within week 1
Implanatation (as a blastocyst)
Vision defect with right temporal lesion
left upper quandrantic anopsia
In the womb dizygotic twins have
2 amniotic sacs, 2 chorions, and 2 placentas
Sign of CN XI lesion
weakness in turning head contralaterally; ipsilateral shoulder drop
Cleft lip mechanism
Failure of maxiallary and medial nasal process fusion
Bronchopulmonary segments contain what
tertiary bronchus and 2 arteries (bronchial and pulmonary)
Ventral pancreatic bud becomes
Pancreatic head
Part of cochlea that picks up high-frequency sound
the base
Truncus arteriosus gives rise to
Ascending aorta and pulmonary trunk
Lesion of right MLF causes
When looking to the left, right eye does not adduct (does not look left)
Round ligament of uterus contents
nothing of importance
Regulatory control of zona fasciculata
Smooth endoplasmic reticulum function
site of steroid synthesis and detoxification of drugs and poisons
Sign of posterior communicating artery aneurysm
CN III palsy
Hypothalamus functions
Thirst, Adenohypophysis control, Neurophypohysis hromones, Hunger, Autonomic regulation, Temperature, Sexual urges (TAN HATS)
Right recurrent laryngeal wraps where
right subclavian
McBurney's point
2/3 of the way from the umbilicus to the ASIS (incision for appendix)
Type IV collagen
basement membrane (FOUR is under the FLOOR)
penile/anal dermatome
S2, S3, S4
Hemidesmosome component
Type II collagen
carTWOlage, hyaline, vitrous body, nucleus pulposus
Endolymph K+ content
High, like ICF
Branchial pouch 1 develops into
middle ear cavity, eustachian tube, mastoid air cells
Meisnner's corpuscles function
light discriminatory touch of hairless skin (glabrous)
Ureter and uterine artery anatomy
Ureters pass under the uterine artery and ductus deferens
Endochondral bone formation
Ossifcation of cartilagenous molds (long bones)
Branchial pouches derived from
Epidermis layers
stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum, stratum basalis (Californias Like Girls in String Bikinis)
Function of posterior hypothalamus
Regulates heat conservatoin
Intramembranous bone formation
Spontaneous without existing cartilage (flat bones)
Blood supply above pectinate line
Superior rectal artery (from IMA)
xiphoid process dermatome
Type I collagen
bONE, tendONe, skin, dentin, fascia, cornea, late wound repair
Celiac trunk vessels
Left gastric, splenic, common hepatic
Tongue pain innervation
V3, IX, X
Anterior cerebral artery supplies
medial surface of brain (leg-foot area of motor and sensory cortices)
Function of medial geniculate nucleus
auditory (Medial for Music)
stomach to duodenum; liver, gallbladder, pancreas, lower respiratory tract (everything but the spleen)
location of bB-cell localization and proliferation
lymph node follicle
Bulbus cordis gives rise to
smooth parts of the left and right ventricle
Male homologue of urethral and parurethral glands (of Skene)
Prostate gland
Nerves passing through superior orbital fissure
Pacinian corpuscle function
pressure, coarse touch, vibration and tension
Loss of hip adduction
Obturator (L2-L4)
Relation of pulmonary artery to each lung bronchus
Right Anterior, Left Superior (RALS)
Passage for CN XII
Hypoglossal canal
Consequence of lesion in cerebellar hemisphere
Intention tremor, limb ataxia
Branchial arch 5 derivatives
Blood brain barrier constituents
Choroid plexus epithelium, Intracerebral capillary epithelium, Arachnoid (CIA)
Consequence of lesion in amygdala
Kluver-Bucy syndrome (hyperorality, hypersexuality, disinhibited behavior)
Findings in Brown-Sequard
Ipsilateral motor paralysis (pyramidal tract), Ipsilateral losss of vibration/proprioception (dorsal column), Contralateral loss of pain/temperature (spinothalamic), ispsilateral loss of all sensation at level of lesion
Iodide teratogenicity
Congenital goiter or hypothyroidism
Central facial lesion
Paralysis of contralateral lower quadrants
Function of astrocytes
physical support, repair, K+ metabolism
Arrangement of cilia microstructure
9+2 arrangement of microtubules
Type X collagen
epiphyseal plate
Signs of UMN injury
minor atrophy, spastic paralysis (clonus), hyperactive DTRs, positive babinksi (UMN = everything is up)
Consequence of lesion in reticular activating system
Free floating nerve in cavernous sinus
Median nerve deficit motor findings
No loss in arm muscles; Loss of forearm pronation, wrist/finger flexion, thumb movements (thenar atrophy)
Lesion of optic chiasm causes
bitemporal hemianopsia
high neck dermatome
IVC crosses diaphragm at what level
Innervation below pectinate line
somatic innervation
Function of suprachiasmatic nucleus
Circadian rhythms
Ductus venosus becomes
ligamentum venosum
Meckel diverticulum description
2 inches long, 2 feet from ileocecal valve, 2% of population, presents in first 2 years, may have 2 types of epithelia (gastric/pancreatic)
Immunoglobulin of B cells activated in Peyer's patches
IgA (secretory)
Loss of plantar flexion
Tbial (L4-S3) TIP=Tibial Inverts and Plantarflexes; you can't walk on your TIPtoes
CN X function
taste (far posterior tongue), swallowing, palate elevation, talking, thoracoabdominal viscera autonomics
Mesonephric ducts develop into
Seminal vesicles, Epididymis, Ejactulatory duct, Ductus deferens (SEED)
Sign of CN V lesion
Jaw deviates toward side of lesion
Perilymph Na+ content
High, like ECF
Brachial plexus injury leading to winged scapula
Long thoracic (from roots C5,C6,C7)
Left ovary/testicle venous drainage
left gonadal vein --> left renal vein --> IVC
Axiallary nerve injury location
Surgical neck of humerus or anterior shoulder dislocation
Tongue motor innervation
Rotator cuff muscles
Supraspinatus, Infraspinatus, Teres minor, Subscapularis
secretory product of Zona fasciculata
cortisol, sex hormones
What allows cilia to bend
Dynein ATPase
Fetal milestones within week 3
Gastrulation (3 germ layers in 3rd week); Primitive steak, notochord, and neural plate
Abnormal opening of penis on ventral side
Branchial pouch 2 develops into
epithelial lining of palatine tonsil
venous drainage above pectinate line
Loss of foot eversion
Umbilical arteries become
Medial umbilical ligaments
Lesion of optic nerve causes
unilateral blindness
Coronary arteries fill during which part of cardiac cycle
Found within the periarterial lymphatic sheath and red pulp of the spleen
T cells
Tongue testing
CN XII, la-la-la
Structures inside carotid sheath
Internal jugular vein (lateral), Common carotid artery (medial), Vagus nerve (posterior) (VAN)
Signs of LMN injury
atrophy, flaccid paralysis, absent DTRs, fasiculations (LMN = everything is down) |
LISA factsheet
Detecting gravitational waves
Name LISA, the Laser Interferometer Space Antenna
Scope LISA is designed to search for and detect gravitational radiation from astronomical sources. In doing so, it will unveil the history of galaxies and black holes in the universe and the physics of dense matter and stellar remnants. LISA will also test some of the fundamental tenets of the theory of gravitation.
Description LISA is a cooperative mission between ESA and NASA.
It is designed to detect 'ripples' in the fabric of space-time created during highly energetic events in which very massive objects undergo strong acceleration. The ripples created are called gravitational waves. This effect was predicted by Einstein's general theory of relativity. Examples of events that cause them are massive black holes swallowing neutron stars or collisions between massive black holes. LISA will be the first mission to detect gravitational waves in space.
The measurements To achieve the goal, three spacecraft form an equilateral triangle with arm’s length of about 5 million km. Each spacecraft is kept centred around two cubes made of a gold-platinum alloy. The cubes float freely in space and the spacecraft protects them from the hazards of interplanetary space. The distance between the cubes in different spacecraft is monitored using highly accurate laser-based techniques. In this manner, it is possible to detect minute changes caused by a passing gravitational waves.
Launch Scheduled for 2018, the mission is currently planned to launch from NASA’s Kennedy Space Centre in the USA on board an Atlas 531 rocket.
Status Under assessment
The current phase was started in January 2005 with a 24-month industrial contract assigned to Astrium GmbH. System engineering activities performed on the mission architecture and design allowed finalisation of the baseline mission design in October 2005 at the Mission Architecture Review. The study has been extended to July 2008 in order to analyse new architectural options in detail.
Journey As per plan the three spacecraft will be launched together. They will independently reach their final orbits around the Sun using their chemical propulsion system. The constellation of spacecraft will orbit the Sun, trailing Earth by 50 million km.
Configuration Unlike the standard configuration of a spacecraft carrying a payload of instruments, LISA’s spacecraft and payload will be closely interconnected,in what can be called a ‘science-craft’. Each science-craft will carry two free-flying proof masses with associated sensors, two identical telescopes, and two optical benches with interferometry measurement systems to measure the relative displacement of each pair of proof masses on different spacecraft.
The advanced technology for LISA will be flight-tested first by the LISA Pathfinder mission.
Last update: 21 August 2009
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gala (n.) Look up gala at
1620s, "festive dress or attire" (obsolete), from French en gala, perhaps from Old French gale "merriment," from galer "rejoice, make merry" (see gallant). Klein suggests the French word is from Italian gala (as in phrase vestito di gala "robe of state"), perhaps from Arabic khil'a "fine garment given as a presentation." Sense of "festive occasion" (characterized by display of finery) first recorded 1777. Quasi-adjectival use in gala day "day of festivities," etc. |
Friday, March 22, 2013
Ferdinand Magellan
Ferdinand Magellan
Ferdinand Magellan - Fernão de Magalhães, was a Portuguese explorer. He was born in northern Portugal, and served King Charles I of Spain in search of a westward route to the "Spice Islands." Magellan's expedition of 1519–1522 became the first expedition to sail from the Atlantic Ocean into the Pacific Ocean The expedition completed the first circumnavigation of the Earth, despite Magellan being killed during the Battle of Mactan in the Philippines.
Ferdinand Magellan was the leader of the first expedition to circumnavigate the real world. He was the first European to sail across the Pacific Ocean and discovered a route by which ships could sail a complete circle around the world. The Straits of Magellan, located at the Southern tip of South America are named for him. This strait proved to be the connection between the Atlantic and the Pacific Oceans.
Magellan was born the son of Pedro Ruy de Magalhaes and Alda de Mezquita in Sabrosa, Portugal in 1480. In Portuguese his name was Fernao de Magalhaes. Of noble parentage, he became a page at the Portuguese court where he learned astronomy and nautical science. At a young age he was preoccupied by voyages of discovery. In 1505, sailing with Francisco d’Almeida, Magellan took part in an expedition to India for the purpose of establishing Portuguese royalty in India. By the year 1510 he had been promoted to the rank of captain. In 1511, he took part in the Portuguese conquest of Malacca, gaining control of the Strait of Malacca. Although it is not absolutely documented, Magellan may have been part of the voyage that reached the Spice Islands in 1511. Returning home in 1512, he took part in the Portuguese expedition to Marocco and was severely wounded, leaving him lame for life. Feeling he was not sufficiently rewarded for his services, Magellan left the army without permission, leading to his disgrace with the king. He gave up his nationality and offered his services to King Charles I (later Holy Roman Emperor Charles V), ruler of Spain in 1517.
Portugal had claimed as theirs the islands of the Far East as a result of the Treaty of Tordesillas of 1494. Magellan claimed that many of them, including the rich Spice Islands, actually lay in Spain’s territory, that Portuguese maps had been falsified to conceal this fact. In 1513, Vasco de Balboa had found an ocean on the far side of the New World discovered by Christopher Columbus. Magellan proposed to the Spanish king an expedition to find a passage through the New World to this ocean and to sail west to the Moluccas, thus proving that the Spice Islands lay on the Spanish side of the line of demarcation. King Charles approved the plan. Magellan took the oath of allegiance in the church of Santa Maria de la Victoria de Triana in Seville, and received the imperial standard. He also gave a large sum of money to the monks of the monastery in order that they might pray for the success of the expedition. After a year of preparations the expedition left Seville in September of 1519 in five small vessels.
Sailing across the Atlantic Ocean he reached South America at the Bay of Rio de Janeiro by December 13th. They arrived at the estuary of the Rio de la Plata by January 10, 1520 and probed for the passage to the vast western ocean. By March 31st, Magellan decided to spend the next six months there during winter storms. During this time, one ship, The Santiago, was wrecked, a mutiny occurred and was quelled, and another ship was lost to desertion headed back to Spain. The voyage was resumed on August 24, 1520. By October he had sighted what he assumed to be the sought after strait. Ships went ahead and reported what they thought to be an ocean beyond. However, this only proved to be another large bay. After deliberating with his navigators, Magellan decided to proceed. Magellan had just sailed through the strait that would later bear his name, the Strait of Magellan. Those straits were originally called the Canal de Todos los Santos (All Saints’ Channel) by Magellan himself. By late November (November 28) Magellan and the three remaining ships finally reached the ocean which seven years earlier, Balboa had discovered. Because of its apparent calmness, he named it Mar Pacifico, the Pacific Ocean.
The voyage proceeded along the coast of South America and on December 18th headed west into the Pacific. One month into the voyage, hardships were encountered. Supplies were depleting, food and drinking water were scarce. Many of the crew died of scurvy. Land was sighted but no landfall was made until Magellan reached the Marianas (or Ladrone) Islands by March of 1521. There he took on more provisions. Landing on the island of Cebu on April 7th, he was received in a friendly manner by the chief and ruler of the island. After eight days, Magellan was able to covert the ruler to Christianity along with hundreds of natives. The ruler agreed to aid him in an attack on the natives of neighboring island, Mactan. There, involved in fighting with natives, Magellan was killed on April 27, 1521.
The two remaining ships were refitted and spices purchased. Under Juan Sebastian del Cano they set sail for the return voyage to Spain. Only one ship, the Victoria, with a crew of only eighteen men and 4 East Indians reached Seville, Spain on September 8, 1522 after a voyage across the Indian Ocean, around the Cape of Good Hope and north through the Atlantic. Completing a voyage of more than three years, they had succeeded in circumnavigating the globe. The spices they brought them amply repaid the expenses of the voyage.
Magellan himself had not succeeded in his principal purpose, to circumnavigate the globe in one voyage. He had, however, provided the skill and determination that made this achievement possible.
There is no greater name than Ferdinand Magellan in the history of discovery. He succeeded in crossing the Pacific from east to west. His voyage laid the foundation for trade in the Pacific between the New World and the East.
Edited Appleton's Encyclopedia, Copyright © 2001 VirtualologyTM
The Catholic Encyclopedia:
An International Work of Reference
on the Constitution, Doctrine, Discipline,
and History of the Catholic Church
By Charles George Herbermann
Edited by Stanley L. Klos 2000
Published by Universal Knowledge Foundation, 1913
Magellan, Ferdinand the first circum-navigator of the world; b. about 1480 at Saborosa in Villa Real, Province of Traz os Montes, Portugal; d. during his voyage of discovery on the Island of Mactan in the Philippines, 27 April, 1521. He was the son of Pedro Ruy de Magalhäes, mayor of the town, and of Alda de Mezquita. He was brought up at the Court of Portugal and learned astronomy and the nautical sciences under good teachers, among whom may have been Martin Behaim. These studies filled him at an early age with enthusiasm for the great voyages of discovery which were being made at that period. In 1505 he took part in the expedition of Francisco d'Almeida, which was equipped to establish the Portuguese vice royalty in India, and in 1511 he performed important services in the Portuguese conquest of Malacca. He returned home in 1512 and took part in the Portuguese expedition to Marocco, where he was severely wounded. On account of a personal disagreement with the commander-in-chief, he left the army without permission. This and an unfavourable report that had been made upon him by Almeida led to his disgrace with the king. Condemned to inactivity and checked in his desire for personal distinction, he once more devoted himself to studies and projects to which he was mainly stimulated by the reports of the recently discovered Moluccas sent by his friend Serrao. Serräo so greatly exaggerated the distance of the Moluccas to the east of Malacca 'hat the islands appeared to lie within the half of the world granted by the pope to Spain. Magellan therefore resolved to seek the Moluccas by sailing to the west around South America. As he could not hope to arouse interest for the carrying out of his plans in Portugal, and was himself, moreover, misjudged and ignored, he renounced his nationality and offered his services to Spain. He received much aid from Diego Barbosa, warden of the castle of Seville, whose daughter he married, and from the influential Juan de Aranda, agent of the Indian office, who at once desired to claim the Moluccas for Spain. King Charles I of Spain (afterwards the Emperor Charles V) gave his consent as early as 22 March, 1518, being largely influenced to do this by the advice of Cardinal Juan Rodriguez de Fonseca. The king made an agreement with Magellan which settled the different shares of ownership in the new discoveries, and the rewards to be granted the discoverer, and appointed him commander of the fleet. This fleet consisted of five vessels granted by the government; two of 130 tons each, two of 90 tons each, and one of 60 tons. They were provisioned for 234 persons for two years. Magellan commanded the chief ship, the Trinidad; Juan de Cartagena, the San Antonio; Gaspar de Qucsada, the Concepción ; Luis de Mendoza, the Victoria; Juan Serrano, the Santiago. The expedition also included Duarte Barbosa, Barbosa's nephew, the cosmographer Andres de San Martin, and the Italian Antonio Pigafetta of Vicenza, to whom the account of the voyage is due.
Third Biography
Ferdinand Magellan ( Portuguese : Fernão de Magalhães , Spanish : Fernando de Magallanes , Sabrosa , 17 October 1480 - Mactan , 27 April 1521 ) was an explorer and navigator Portuguese . Began the first circumnavigation of the globe in the service of the crown Spanish . He was the first from Europe to the West in direct Asia and the first European to sail in ' Pacific Ocean . The story of his journey is received by the notes of one of his men-at-arms, the Vicenza Antonio Pigafetta , who worked for the rest of his life to keep alive the memory of Magellan and his business.
Ferdinand Magellan was born into an aristocratic family of impoverished Sabrosa in the province of Trás-os-Montes , in Northern Portugal. His father, Pedro Rui de Magalhães, married Alda de Mesquita, was the mayor of the town. Magellan had a brother, Diego de Sousa, and a sister, Isabel.
At the age of ten years Magellan lost their parents. Two years later, following his brother, became a page at the court of King John II in Lisbon . Here he enjoyed the generous education due to the young noblemen. In 1505 , at age 25, he was sent to India , where he served under the Viceroy Francisco de Almeida . Soon he earned an honorable mention for having thwarted a mutiny and saved lives. From 1506 he participated in an expedition directed to the Spice Islands . During this expedition he gained promotion to captain ( 1510 ), but shortly after he lost his patent captain for having run away from his ship flotilla to look for new lands to the east. Under the command of Alfonso de Albuquerque took part in the conquest of the strategic port of Malacca in today's Malaysia .
When he returned home, he took part in 1513 in an expedition to Morocco , where he fought in the Battle of Azamor , bringing the damage to knee. It was subsequently alleged to have engaged trade with Muslims : this story that the 15 May 1514 led to her dismissal with disgrace from the service to the Portuguese crown.
At the same time Magellan came into possession of a map that suggested a move towards the ' Pacific Ocean just south of the Rio de la Plata . He was convinced of being able in this way to find a way for the ' Asia shorter than around Africa. This would have allowed us to discover a passage to the south-west connecting the Atlantic with the Pacific. This passage, geographically considered likely but which no one had credible reports, idly from time cartographers.
In fact, the strategic aim of the expedition was to find a new sea route to the Spice Islands, in the archipelago of the Indonesian Moluccas , preventing the circumvention of Africa whose western and southern ports were all in the hands of Portugal . If possible, one should also prove that the Moluccas were actually dell'antimeridiano west of the demarcation line that, according to the treaties, divided the spheres of influence and possession of colonial Spanish and Portuguese. Of course, not least would be the possible discovery of new lands to be annexed to the already vast empire of the King of Spain.
Convinced Charles V to finance the enterprise, the expedition of five ships sailed September 20, 1519 from San Lucar de Barrameda (Aug. 10 from the port of Seville ). On 28 November 1520 , left with only three ships (one was wrecked, the other had deserted), crossed the strait that bears his name, and for the first time in a big ocean forwarded unknown to Westerners, that for all three months at sea in the direction of north - west was quiet to the point that he was given the name of the Pacific . In March 1521 he reached the Mariana Islands and then the Philippines , called Island of San Lazzaro, where he met his death at the hands of the natives.
According to the account of Pigafetta, in the Philippines , Magellan was able to convert the king of the island of Cebu , Rajah Humabon and many of his subjects to Christianity . Cebu when he submitted to the Spanish crown, a rebellion broke out on the nearby island of Mactan . Magellan decided to use force to conquer Mactan Spain and Christianity. When he landed on the morning of 27 April 1521 in Mactan, was killed by the inhabitants of the island.
The trip ended on 6 September 1522 , when the Victoria , the only surviving ship, returned to the port of departure after having completed the first circumnavigation of the globe in two years, 11 months and 17 days. On board the small ship (85 tons), which was taking on water and a canopy of luck, there were only 18 men of the 234 parties, including sailors and soldiers. Among the survivors there were two Italians, Antonio Lombardo, said Pigafetta , who wrote the history of the expedition, and Martin de Judicibus.
The circumnavigation was not the end of Magellan, he just wanted to find the passage to the west to the Spice Islands and India.
Only Juan Sebastián elCano, along with Antonio Pigafetta , recognized the real importance of the journey around the earth. He and his 17 men surviving the honor of having taken the first continuous journey around the Earth. This also applies to the 13 men who were prisoners of the Portuguese in Cape Verde, which lies further to the west than in Spain.
But Magellan himself in his life had completely circumnavigated the earth: from 1505 to 1511 had been in the East, where he had also visited the Moluccas. Although there would be back in 1521 had come to the Philippines thus having already crossed the meridian of the Moluccas.
However, the first person to have crossed all meridians may have been the slave and interpreter Enrique , probably from the Philippines. Purchased in 1511 by Magellan in Sumatra, had accompanied this in all his subsequent trips. On the death of Admiral in Mactan, Enrique fled home aided by the king of Cebu, so at least the story of Antonio Pigafetta. But Enrique could also have been the source Malay : in this case may never have completed the circumnavigation. Magellan died in a clash with the natives of Mactan Cebu.
Magellan's voyage proved definitively four things: that the Earth is a sphere, the circumference of the planet is much greater than they ever believed all geographers, that America can be circumnavigated like the African continent that are lost 24 hours if you follow the path of the sun from west to east. This observation provided the basis for further speculation of interest on the physical and metaphysical nature of time and eternity.
From the material point of view, given the long distances (the Victoria had covered 69,000 km in three years to return to Spain), Magellan's voyage could not be a viable alternative to the so-called Spice Route controlled by the Portuguese. Spain and Portugal both claimed possession of the Moluccas by the Treaty of Tordesillas , and only in 1529 the dispute could be resolved with the Treaty of Zaragoza , with whom Spain had to give up its claims on the area. However, even in the sixteenth century, the Spaniards were able to conquer Guam and the Philippines , which would have remained in their hands until 1898 .
By: Stanley Yavneh Klos
Edited By: Naomi Yavneh Klos, Ph.D.
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General Question
Hawaii_Jake's avatar
Why do the British say maths and people in the US simply call it math?
Asked by Hawaii_Jake (28275points) July 2nd, 2012
As asked.
Observing members: 0 Composing members: 0
25 Answers
ragingloli's avatar
because the full word is mathematics
Response moderated (Unhelpful)
CWOTUS's avatar
I guess we should all be glad they don’t call it “the maths”.
I suspect it has to do with how many branches of mathematics there are. That, and the fact that the Brits like to add extra letters to their words, for colour and such. Sometimes they add whole extra syllables, such as with aluminium and jaguar (where that word is spelled / spelt the same on both sides of the Atlantic, but pronounced differently there).
Dr_Lawrence's avatar
The British expression acknowledges that there are many sub-disciplines in Mathematic*s*.
Dr_Lawrence's avatar
@CWOTUS It is only Americans who omit letters still used by all other users of the English letter. American dictionary editor Webster introduced these misspellings and omissions to create a distinctive American variant of the language. Distinctive does not meant improved. Mathematics is always a plural noun even where people fail to include the ‘s’.
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CWOTUS's avatar
You may call them misspellings, @Dr_Lawrence, but I call them corrections. (I haven’t called ‘nite’ a correction over ‘night’ yet, and such like, but I might. I just mite.)
SavoirFaire's avatar
It has to do with different conventions for abbreviation—conventions which arose haphazardly (in the typical manner of natural language evolution). Interestingly, the abbreviation “math” is older than the abbreviation “maths.” The former first appeared in 1847, whereas the latter did not turn up until 1911. The word “mathematics” originally referred to any discipline that included calculations as part of its practice. This is why the full word has an “s” at the end, but it is not—on its own—an explanation of why some people say “math” and others say “maths” (as both groups say “mathematics”).
@Dr_Lawrence Canadian English contains some of the spelling variants typically identified as American and some of the spelling variants typically identified as British. They also call association football by the name “soccer” and use “fanny” to mean “buttocks” (rather than “vulva”). The English language is not so easily divided into American versus everyone else.
Furthermore, the British have indeed added letters to existing words. “Aluminum” came before “aluminium” (though only by a matter of months), but the latter was suggested as a replacement for the former on aesthetic grounds. Usage was then inconsistent in both North America and Europe until the early 20th century when a combination of market forces and the American Chemical Society officially adopting “aluminum” made that spelling standard in North America. Meanwhile, it wasn’t until 1990 that IUPAC decided to give its blessing to “aluminium.”
And finally, “mathematics” is a collective noun, like “family” or “physics.” All of these are treated as singular for purposes of verb conjugation (“mathematics is fun,” “my family enjoys kayaking,” “my favorite thing to study is physics”), so insisting that these words are plural only carries so much force as an argument. None of this is meant to suggest that the British variants are incorrect and the American ones correct, but only that the reverse is no more true. These are differences of dialect, not clear errors like using a comma as terminal punctuation.
Response moderated (Unhelpful)
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Adagio's avatar
We call it maths in NZ too, I’ve always found it strange to hear it called math.
bolwerk's avatar
Is spelling the only thing British have left to be chauvinist about? Don’t British have slightly less wide girths? Maybe a better primary/secondary education system?
The “correct” (that is, socially sanctioned) way to spell is how everyone else around you spells.
Response moderated (Off-Topic)
CWOTUS's avatar
I don’t suppose that y’all will let Mark Twain have the last word on this, but you should:
A Plan for the Improvement of English Spelling
by Mark Twain
For example, in Year 1 that useless letter “c” would be dropped to be replased either by “k” or “s”, and likewise “x” would no longer be part of the alphabet. The only kase in which “c” would be retained would be the “ch” formation, which will be dealt with later. Year 2 might reform “w” spelling, so that “which” and “one” would take the same konsonant, wile Year 3 might well abolish “y” replasing it with “i” and Iear 4 might fiks the “g/j” anomali wonse and for all. Jenerally, then, the improvement would kontinue iear bai iear with Iear 5 doing awai with useles double konsonants, and Iears 6–12 or so modifaing vowlz and the rimeining voist and unvoist konsonants. Bai Iear 15 or sou, it wud fainali bi posibl tu meik ius ov thi ridandant letez “c”, “y” and “x”—bai now jast a memori in the maindz ov ould doderez—tu riplais “ch”, “sh”, and “th” rispektivli. Fainali, xen, aafte sam 20 iers ov orxogrefkl riform, wi wud hev a lojikl, kohirnt speling in ius xrewawt xe Ingliy-spiking werld.
Response moderated (Off-Topic)
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Nullo's avatar
We could take a romantic angle where Americans are so busy making progress that one extra ‘s’ has to go, whereas the British, characterized here by elegance and precision and good taste want the ‘s’ there because it’s better.
Honestly, I have no idea.
For what it’s worth, Italian uses the singular form, giving us “la matematica.”
Response moderated (Off-Topic)
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mattbrowne's avatar
Most of the time Americans prefer shorter words, e.g. color instead of colour, counseling not counselling. Time is money.
rooeytoo's avatar
For the same reason aussies say “sport” and yanks say “sports.”
That shoots your theory out of the water @mattbrowne.
jca's avatar
@CWOTUS: Another example is the Brits pronunciation of “film” which they pronounce (or at least the Irish pronounce) “fill-um.”
Nullo's avatar
@mattbrowne Perhaps it’s not length as much as it is confusing embellishment? That extra ‘u’ doesn’t help anybody, while “sports” underscores the wide range between the shot-put and cheerleading.
bolwerk's avatar
Could the major difference between either of these (math/maths, sport/sports) be whether it is being conceptualized as a definite or indefinite quantity?
Nullo's avatar
@bolwerk British and American English both recognize “mathematics” as the correct full spelling, the only difference being in the short form.
The OED points out that “sport” originally referred in a general sense to recreational activity. Sport is amusement, and sports are things that one does for sport. And now ‘sport’ looks funny when I write it.
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Golden Rice, Source: Wikimedia Commons
The "California Right to Know Genetically Engineered Food Act," also known as Proposition 37 ("Prop 37"), advances the deeply misguided aspirations of several powerful special interests, including the plaintiffs' bar, environmentalists, and public health activists. Part of this ballot initiative would require all raw and processed foods whose production was impacted in any way by biotechnology to be labeled as such. Prop 37 allows private citizens (i.e., lawyers) to sue farmers, distributors, grocers, and food companies for $1,000-a-day fines and punitive damages if a product is out of compliance.
The mandated labeling and the private enforcement provisions of the initiative have received an increasing amount of attention. There is, however, another part of Prop 37 which has been subjected to very little public scrutiny. That is about to change, however, because this section contains a possible poison pill that may sink the entire initiative. In addition to requiring "genetically engineered" labels, Prop 37 prohibits the use of terms such as "natural" and "all natural" in product packaging and any advertising and promotional materials.
This prohibition of course applies to products impacted by biotechnology. But it also can apply to other foods regardless of whether or not they have been genetically engineered or include ingredients that have been. The California Attorney General's title and summary of Prop 37 reflects this, as does the independent, non-partisan Legislative Analyst's Office's summary. The "Yes on Prop 37" crowd urged a state judge to clarify that the "natural" marketing ban only applies to genetically engineered processed foods. But on August 10, the judge denied their request, instead ordering a minor wording change to the Legislative Analyst's Office's summary.As a result, the "natural" marketing ban is entirely counterproductive to the purported larger aims of Prop 37. Consumers who want to avoid processed goods that contain chemical or synthetic ingredients will now find it harder to distinguish between products if none of them can be labeled "all natural." Prop 37's marketing ban also establishes an entirely absurd, completely radical notion of "natural." Under the broad interpretation:
• Olives sold in bulk at a store, natural; olives bottled in oil, unnatural (due to canning)
• Apples sold individually, natural; apples cut up and packaged individually for your convenience, unnatural (due to cutting and packaging)
• Unshelled peanuts, natural; peanuts ground up and canned with no added ingredients (i.e. peanut butter), unnatural (due to pressing and canning) |
What is Country Risk?
Country Risk Definition. Country Risk refers to the probability that changes in the business environment in another country where you are doing business may adversely impact your operations or payment for imports resulting in a financial loss. Country Risk also includes Sovereign Risk, which is a subset of risk specifically related to the government or one of its agencies refusing to comply with the terms of a loan agreement. Causes of Country Risk include political, macroeconomic mismanagement, war or labor unrest resulting in work stoppages. Political changes may come about due to a change in leadership, control by a ruling party, or war. New economic policies may be instituted resulting in expropriation of assets, nationalization of private companies, currency controls, inability to expatriate profits, higher taxes or tariffs, and a host of minor impacts. On a macroeconomic level, countries may pursue unsound monetary policy resulting in inflation, recession, higher interest rates, and shortages in hard currency reserves. The recent debt problems in Europe highlighted sovereign risk issues in Greece and other member states of the Eurozone when loan defaults were a real concern for banks holding the respective loan paper.
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Selection of voltage for DC systems
For example whether to select 24V DC system or 48V DC system or 110V DC system. What factors are to consider for this selection of like UPS or solar power system?
The same thing that made Edison's DC system a loser, Ohm's Law and voltage drop. Remember Ohm's Law tells us that for a given load the higher the applied voltage the lower the current through the wires. So for a given conductor size higher voltage means more power delivered for the same ampacity of the wire. As an engineer you should know that you have the choice to keep the voltage low and increase the wire size, or to raise the voltage and use smaller wires.
In addition, the voltage chosen can also be a function of the amount of energy storage capacity (kWh) that is required for applications like UPS or battery backup.
Battery manufacturers produce cells with fixed storage capacities given in units of amp-hours based on a cell voltage of approximately 1.8-2.2 volts/cell. If you require a certain energy storage capacity of E [kWh], then pick a standard battery storage capacity like C [amp-hour] and voltage V. The battery energy storage capacity will then be equal to E = CV and the number of cells will be roughly equal to V/2-volts-per-cell if one series string is designed. Other string combinations are also possible.
To refine your calculations further, the depth of discharge (minimum voltage) needs to be considered (based on battery chemistry) along with the number of charge/discharge cycles to determine the battery lifetime. Battery manufacturers can assist with these calculations if they are provided with the design requirements for the application.
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friends together smiling
Whether you're a former smoker or a current smoker who is trying to quit, summer brings on temptations that can make it hard to stay away from cigarettes. Pool side parties and barbecues can make you crave a cigarette, and your friends who still smoke may try to tempt you with their unhealthy habit.
But there's no need to give in to the social pressure to smoke. It is possible to stay smoke free, or even to quit smoking, without sacrificing a single summer party. By adopting a few simple strategies, you can stay on track with your health goals and keep cigarettes out of your summer.
Select a Substitute
Most smokers are addicted to the taste and sensation of smoking. Fortunately, summer parties usually have plenty of options to keep your hands busy and your taste buds happy.
To combat your cravings for these physical elements of smoking - and keep nicotine at bay - try to distract yourself with a healthier habit. Chewing gum can be a helpful substitute, or grab a few crunchy treats, such as carrot sticks or nuts. Even a less-than-healthy snack, such as a piece of hard candy, is better than picking up a cigarette.
Don't Linger with Smokers
You needn't avoid your smoking friends at a party - but you also don't need to hang around them every time they light up. Former smokers often describe missing the social element of smoking, since chatting during a cigarette is an easy way to make friends. There are plenty of other ways to meet people at a party, so make sure you spend time with circles of non-smokers too.
Instead of hanging with the smoking crowd outside the house, or in a backyard cluster, find some non-smoking friends or meet new people. Try the indoor crowd if you need to separate yourself from secondhand smoke. If cooking is in progress in the kitchen, offer to pitch in. If a game is underway in the living room, ask if you can join the fun. Better yet, suggest your own favorite board game or pastime.
Remember the Reasons
In the heat of the moment, when people are lighting up around you, it may seem like the advantages of smoking outweigh your reasons for wanting to quit. Don't let this happen. Remind yourself of why you've stopped smoking, or why you're trying to free yourself of cigarettes.
In case you need a few reminders, there are numerous health benefits associated with a smoke-free lifestyle. Smoking damages virtually every organ in your body, and can lead to numerous forms of life-threatening cancers, including lung, mouth, and throat cancer. According to estimates smoking kills around 900,000 people in India every year. Secondhand smoke is also harmful to those around you.
When you feel the urge to smoke, do whatever it takes to remind yourself of the dangers of smoking. Try writing out a list of reasons, and keeping it in your wallet to refresh your memory when you're feeling tempted. Alternatively, ask a non-smoking friend or family member to help you stay on track, and give you support when you need it.
Keep It Real
If ever you waver in your desire to quit, or to stay smoke free, it may help to be aware of these facts and statistics from the Tobacco Control Foundation of India (TCFI): Smoking is limited only to human species; the first smoking experience is not pleasurable. Less than 30 percent of the total population in India now smokes. Non-smokers have smokers outnumbered by over 70 percent. So even if you feel like an outsider among the smokers in a summer crowd, remember that you're far from alone. You're part of the majority of Indians who have decided to prioritize health and longevity over an unhealthy habit. |
How to Find Extraterrestrial Life
07/05/2012 09:01 am ET | Updated Feb 12, 2013
A team of mostly Dutch astronomers have used the Very Large Telescope -- situated atop a barren ridge in the Chilean Andes -- to examine a planet hugging the star Tau Bootis, 51 light-years away. The planet is hellishly hot and impressively hefty; it packs the mass of a half-dozen Jupiters. But the truly interesting thing is that the VLT was able to detect this world's elusive infrared glow. Applying a bit of spectral analysis, the team uncovered carbon monoxide in its atmosphere.
Now carbon monoxide, familiar to many as a noxious tail pipe emission, is just another of the simple molecules that are as common as clover in the cosmos. No biggie. But could this same technique be used to find biologically relevant gases, such as ozone (a form of oxygen) or methane? If so, it would be a method for discovering life from afar.
Frankly, today's telescopes would have a hard time pulling this off. But new, outsized instruments sporting mirror diameters of 100 feet or more are in the offing. They're complex and they're costly, but they're also game changers, and could offer a life-detection scheme as promising as sending people or probes to Mars.
Which brings me back to the summer of 2006, when I was preparing a talk about the search for extraterrestrial life for a group near San Francisco. The newspapers were thick with stories relevant to biology beyond Earth: ice on Mars, discovery of a few more planets, etc. If you paid attention to it all, you'd be swamped. But it struck me that by stepping back from this daily dose of astronomical revelation, it was clear that all these stories neatly fell into three categories -- three approaches to determining if there's anything alive out there.
In other words, there's a three-way horse race to discover extraterrestrial life. For your consideration and contemplation, I list this trio of trotters below:
1. Discover life nearby. This is horse number one, and where you'll find the big effort and the big money. National space agencies back this nag by sending probes that might eventually ferret out microbes in the dark aquifers beneath Mars' sterile landscape, or in the hidden oceans of such moons as Europa, Callisto, Ganymede, Titan or Enceladus.
This is the search for life in our solar system, a holy grail ever since Galileo first swung a telescope towards the moon. But so far, no joy. Despite tantalizing suggestions of fossilized microbes in meteorites, puzzling and possibly biogenic methane gas in the martian atmosphere, and a long-standing controversy over the Viking lander experiments of nearly 40 years ago, there's still no Exhibit A that points unequivocally to biology in our own back yard.
Nonetheless, the search goes on, becoming ever more extensive and more sophisticated. It's like Prince Henry the Navigator, sending ship after ship into the South Atlantic, hoping to find a route to the East. He eventually succeeded, and maybe we will too.
2. Sniff it out. Horse number two is the strategy described at the start of this article. A decade ago, NASA had plans to build a space-based, infrared telescope called the Terrestrial Planet Finder. It could both image exoplanets as well as do the sort of spectral analysis that might detect atmospheric gases caused by biology. Alas, the TPF is presently in a state of "indefinite hold," which many researchers think is a euphemism for rigor mortis.
But the idea is good, and either something like the TPF will eventually fly, or the humongous telescopes currently on the drawing boards will use their cyclopean mirrors to search out life around other stars by sensing its exhaust gases.
3. Eavesdrop on ET. Otherwise known as SETI, this third horse is an effort to detect radio signals or laser flashes from technically savvy extraterrestrials. The down side? Life able to build transmitters or lasers is surely less widespread than the type of single-celled organisms that might be discovered by schemes 1 and 2. So SETI will have to search farther and wider to win this race. The up side? It could, in principle, succeed tomorrow.
Of course, some folks consider SETI a long shot. But it offers a big payoff if it noses across the finish line first: Namely, life (or at least intelligence) that could have something interesting to say.
So what are the chances that any of these horses will make it into the stretch?
That's a big guess of course, and not much more than a guess. But unless you think that life is highly improbable -- that in a galaxy filled with planets and the basic molecules of biology, life only seldom appears -- then it's hard to believe that all three of these horses will scratch.
As to who's favored to prance into the winner's circle, my opinion is that, a priori, each of the contenders boasts roughly equal odds. In the next two decades, we'll see yet more robotic explorers on Mars, and possibly even on the more seductive satellites of the outer solar system. That's good news for horse one. But within the same time frame, large telescopes and possibly a cousin to the Terrestrial Planet Finder will be analyzing the light from planets around nearby stars. And SETI experiments -- assuming that continued funding can be found -- will increase the number of stellar systems examined by a factor of a thousand.
So the next time you check out the myriad science stories here and elsewhere that pertain to the matter of life beyond Earth, consider this simple way to categorize their relevance. The field is small, the contenders well-matched, and the horses are out of the gate. |
IB syllabus > redox(sl)
IB syllabus for first examinations 2016
9.3 - Reactivity
9.3.1: Deduce a reactivity series based upon the chemical behaviour of a group of oxidising and reducing agents. Examples include displacement reactions of metals and halogens. Standard electrode potentials or reduction potentials are not required.
Reactivity series
It is possible to organise a group of similar chemicals that undergo either oxidation or reduction according to their relative reactivity. Oxidation (and reduction) is a competition for electrons. The oxidising species (agents) remove electrons from other species and can force them to become reducing agents (releasers of electrons)
A good example of this competition for electrons is the behaviour of metals. Metals always react by losing electrons (oxidation) they are then reducing agents. However if a metals is in competition with metal ions the more reactive metal can oblige the less reactive metal (in the form of ions) to accept electrons. This is called a displacement reaction.
Example: Zinc reacts with a solution containing copper ions.
The zinc metal is more reactive than copper metal and so it can force the copper metal ions to accept electrons and become metal atoms.
Zn(s) Zn2+(aq) + 2e
Cu2+(aq) + 2e Cu(s)
The zinc metal passes its electrons to the copper ions. We observe that the zinc develops a pink layer of coper on its surface and the blue copper ion solution fades in colour.
We say that the zinc displaces the copper ions from solution.
Experimental observations
If we observe that there is a reaction between a metal and another metal ion in solution this tells us that the solid metal is more reactive than the metal of the dissolved metal ions.
Given this information we can deduce that the most reactive of the three metals is iron, followed by copper, followed by silver. This allows us to arrange the metals into a reactivity series based on these specific reactions
Reduction of metal oxides by metals
metal A + metal B oxide metal A oxide + metal B
When a metal A is heated with a metal B oxide there will be a reaction if the free metal A is more reactive than the metal B of the metal B oxide. This is because the metal B in the metal B oxide is in the form of a metal ion - it has already lost electrons.
There is a competition between the metal ion (in the oxide) and the free metal for the electrons. The more reactive of the two metals will win the competition. Consequently if there is a reaction between a metal and a metal oxide then this tells us that the free metal is more reactive than the metal in the metal oxide.
Experimental observations
We can use this information to arrange the metals in order of reactivity
Sodium most reactive
Copper least reactive
Sodium has the greatest electron releasing power (and conversely the copper ions - Cu2+ - would have the greatest electron attracting power)
Predictions from reactivity series
Once a reactivity series is produced it can be used to predict reactions of pairs of reactant. For example in the table above it should be appreciated that magnesium will react with copper oxide reducing it to copper metal.
Any metal that is more reactive will react with compounds of less reactive metals.
Reactivity series involving non-metals
Metals react by losing electrons - they are reducing agents. Non-metals react by gaining electrons - they are oxidising agents. In the same way that metals can be ordered in terms of reducing strength, the non-metals can be ordered in terms of their oxidising strength. The halogens are a typical example of a non-metal reactivity series.
Reactivity of the halogens
Fluorine most reactive
Iodine least reactive
Fluorine is so reactive that we cannot isolate it in the laboratory very easily, as it reacts with both water and glass. As a result we don't usually deal with fluorine at pre-university level
but compare only the other three (astatine is very rare and radioactive)
Do not confuse this order of reactivity with that of the metals - these are non-metals, their reactivity is in terms of oxidising power - i.e. chlorine is the best oxidising agent out of chlorine, bromine and iodine.
1. Chlorine will displace bromine from solutions containing bromide ions
Cl2 + 2Br- Br2 + 2Cl-
In this reaction the chlorine is oxidising the bromide ions by removing an electron from them. Bromine is liberated from the solution and may be detected by its orange/red colour
2. Bromine will displace iodine from solutions containing iodide ions
Br2 + 2I- I2 + 2Br-
In this reaction the bromine is oxidising the iodide ions by removing an electron from them. Iodine is liberated from the solution and may be detected by its orange/brown colour which turns blue/black in the presence of starch indicator.
It is predictable, then, that chlorine will also displace iodine from a solution containing iodide ions
9.3.2: Deduce the feasibility of a redox reaction from a given reactivity series. Students are not expected to recall a specific reactivity series.
Prediction of feasibility
Once a reactivity series is constructed depending on the reduction or oxidation ability of each species, we can use it to predict the feasibility (probability) of a reaction occurring between any two pairs of reactants.
If one of the substances is a reducing agent - i.e. it reacts by losing electrons then this must react with an oxidising agent - i.e. a species that gains electrons.
K K+ + 1e
best reducing agents (left hand side species)
Mg Mg2+ + 2e
Zn Zn2+ + 2e
Fe Fe2+ + 2e
Cu Cu2+ + 2e
H2 2H+ + 2e
2I- I2 + 2e
2Br- Br2 + 2e
2Cl- Cl2 + 2e
best oxidising agents (right hand side species)
Any species from the right hand side of one of the redox equilibria (the oxidising agent) can be predicted to react with any species above it on the left hand side of the redox equilibria (the reducing agent).
The species on the right hand side of the equilibria will gain electrons to go to the right hand side. They can only gain these electrons form species that are abopve them on the left hand side of the series.
We can therefore predict that chlorine (right hand side) will react with copper (left hand side) to form copper ions nad chloride ions according to the equation:
Cl2 + Cu Cu2+ + 2Cl-
Similarly, we can predict that iodide ions (left hand side) will NOT react with zinc ions (left hand side) as the zinc ions are poor oxidising agents and the iodide ions poor reducing agents.
Note: although a reaction may be predicted as feasible it does not mean that it will happen spontaneously. If the activation energy is high then it may need an extra "push" to get it going. - for example the reaction between chlorine and hydrogen needs a spark or ultraviolet light and then it is explosively fast.
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The Supreme Court
Burger Court
After successfully stopping the nomination of Abe Fortas as Chief Justice, the Republicans won overwhelmingly in the next election and President Richard Nixon got to appoint Chief Justice Earl Warren's successor. He wanted to find someone who would reshape the court in his image and he chose Warren Burger.
Burger was not a forceful leader and was never able to overturn any of the Warren Court's rulings. Instead his court was led by the moderate justices who tried to find middle ground. While it might not have been his intention when he took over the court, his court's ruling on abortion set off a social struggle that continues to split the nation today.
By the end of the Burger court the idea of judicial restraint died and the appointment of activist justices seemed to be the norm for the foreseeable future. This battle between conservative versus liberal activism still divides the court, and the country, today.
Chief Justice Warren E Burger's official portrait by photographer Robert Oaks.
Chief Justice Warren E Burger's official portrait by photographer Robert Oaks.(From the Collection of the Supreme Court of the United States)
Let's take a look at how all this got started and how the Burger Court was steered by the middle, and then I'll review a couple of landmark cases, including one that led to the first resignation of a U.S. president.
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logical positivism
logical positivism, also known as logical or scientific empiricism, modern school of philosophy that attempted to introduce the methodology and precision of mathematics and the natural sciences into the field of philosophy. The movement, which began in the early 20th cent., was the fountainhead of the modern trend that considers philosophy an analytical, rather than a speculative, inquiry. It began in the group called the Vienna Circle, which formed around Moritz Schlick when he occupied (1920s) a chair of philosophy at the Univ. of Vienna. Among its members were the philosophers Friedrich Waismann, Otto Neurath, Rudolf Carnap, Herbert Feigl, and Victor Kraft, and the mathematicians Hans Hahn, Carl Menger, and Kurt Gödel. The movement soon had a widespread following in Europe and the United States. Among those philosophers whose work was influenced by the Vienna Circle are A. J. Ayer and Gilbert Ryle. The position of the original logical positivists was a blend of the positivism of Ernst Mach with the logical concepts of Gottlob Frege and Bertrand Russell, but their inspiration was derived from the writings of Ludwig Wittgenstein, who lived for a time near Vienna, and G. E. Moore. The Vienna Circle in general subscribed to Wittgenstein's dictum in Tractatus Logico-Philosophicus that the object of philosophy was the logical clarification of thought; philosophy was not a theory but an activity. The logical positivists made a concerted effort to clarify the language of science by showing that the content of scientific theories could be reduced to truths of logic and mathematics coupled with propositions referring to sense experience. They held that metaphysical speculation was nonsensical, propositions of logic and mathematics tautological, and moral or value statements merely emotive. They championed the highly influential verification principle, from which it follows that a proposition has meaning only if some sense experience would suffice to determine its truth. The Vienna Circle disintegrated after the Nazis took control of Austria in the late 1930s. The influence of the movement, as a movement, ended c.1940. However, the concepts of the movement, particularly in its emphasis on the function of philosophy as the analysis of language, has been carried on throughout the West.
See A. J. Ayer, ed., Logical Positivism (1959, repr. 1966); E. Gellner, Words and Things (rev. ed. 1968, repr. 1979).
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December 7, 2016
Homework Help: SS7R Question/Help! (plz read)
Posted by Laruen on Sunday, February 12, 2012 at 3:44pm.
The American Revolution
From 1763 through 1776 the American colonies sprit of rebellion was escalating. After a long period of being ignored, England put harder rules over the colonist. Economic, political, and social factors made the colonist take steps that led to their independence.
According to Document 1 and 3, England treats the colonies as if they were children. They always tax colonist so that way they won’t have any money. The British taxed them after the French and Indian war. The colonists were angry and tried to over throw the king. They didn't have a lot of rights. In the Boston Massacre, British soldiers killed 5 colonists, Paul Revere’s painting increased anti – British feelings.
Thomas Paine wrote “Common Senseâ€. They’re some quotes in Thomas Paine’s “Common Sense about Britain mistreating the colonies. He feels that Britain has been mistreating the colonies and “bullying†or fighting them. He asks the colonist to fight for independence as they were being mistreated by Britain rights such as life, liberty, and pursuit of happiness.
What should I write for my conclusion??? I know I know they are some editing mistakes.
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Satellites Reveal Mystery of Large Change in Earth's Gravity Field
August 5, 2002
graphic of Earth gravity field since 1997
Earth gravity field since 1997 links box
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Satellite data collected since 1998, including data from the U.S./French ocean-observing satellite Topex/Poseidon, managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., indicate the bulge in Earth's gravity field at the equator is growing, and scientists think that the ocean may hold the answer to the mystery of how the changes in the trend of Earth's gravity are occurring.
Before 1998, Earth's equatorial bulge in the gravity field was getting smaller because of post-glacial rebound that occurred as a result of the melting of the ice sheets after the last Ice Age. When the ice sheets melted, land that was underneath the ice started rising. As the ground rebounded in this fashion, the gravity field changed.
Currently, Earth has a significant upward bulge at the equator, and a downward bulge at the poles. "Observations of the Earth's gravity field show that some phenomena are counteracting the gravitational effects of post-glacial rebound. Whereas the rebound has been decreasing the bulge in the Earth's gravity field at the equator, this recent phenomena is causing the bulge to increase," Cox said. Such changes in the gravity field can be sensed using ultra precise laser tracking of satellites to observe tiny changes in the orbits of those satellites and by tracking changes in the length of day or rotation of the Earth.
Cox and colleague Dr. Benjamin Chao, also of Goddard, have ruled out the atmosphere as the cause. Instead, they suggest a significant amount of ice or water must be moving from high latitude regions to the equator, and oceans could be the vehicles of this movement.
Estimates of today's glacier and polar ice melting are too small to explain the recent changes in the gravity field. If melting ice were the cause of the recent changes in the gravitational field, it would require melting a block of ice 10 kilometers (6.2 miles) on each side by 5 kilometers (3.1 miles) high every year since 1997 and pouring it into the oceans.
"The recent reports of large icebergs calving in Antarctica can't explain this, because they were already floating in the ocean," Cox said. Further, radar altimeter observations of the average sea level rise provided by Topex/Poseidon show no corresponding change in the rate of the global sea level increase.
In 2002, NASA launched the JPL-managed Grace and Jason Missions, which will help to more precisely track and explain these sorts of changes in the Earth, and will launch the Icesat mission this winter. Aquarius, a JPL-managed mission that is part of NASA's Earth System Science Pathfinder small-satellite program and is proposed for launch in 2007, will provide the first-ever global maps of salt concentration in the ocean surface needed to understand heat transport and storage in the ocean.
For more information and images on Topex/Poseidon and Jason, please see:
More information on Grace may be found at:
Contacts: JPL/Alan Buis (818) 354-0474
Goddard Space Flight Center/Robert J. Gutro (301) 286-4044
NASA Headquarters/David E. Steitz (202) 358-1730
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Volcanic Lakes Spew Large Amounts of Carbon Dioxide
Lake Nyos, which spewed out high levels of carbon dioxide 25 years ago, killing 1,700 people.
Credit: USGS
Lakes that form on and around volcanoes can spew out significant amounts of the global warming gas carbon dioxide, researchers have found.
These new findings could help scientists refine their models on how Earth's climate is changing.
Called volcanic lakes , these bodies of water form either in the craters that are left after a volcano explodes, the calderas left after a volcanic peak or flank collapses, or after lava, ash or mud from volcanoes dam up rivers and streams.
It's a well-known fact that volcanic lakes could release carbon dioxide. Twenty-five years ago, a volcanic lake in Cameroon, Lake Nyos, released lethally high levels of the gas, killing 1,700 people in the surrounding area. This and other tragic incidents revealed that such lakes could be major sources of the global warming gas, which is most likely given off by magma underneath these lakes or rocks heated by such magma.
To see just how much carbon dioxide volcanic lakes as a whole might belch out, scientists randomly sampled 24 volcanic lakes in Nicaragua, Guatemala, El Salvador, Costa Rica, Japan, Cameroon, the Philippines, France and Germany with sensors floating in miniature inner tubes. They next used their findings to project how much of the gas the estimated 769 volcanic lakes worldwide belch out each year.
Surface volcanoes emit roughly 300 million metric tons of carbon dioxide annually, and the researchers calculate that volcanic lakes release a substantial amount, too about 117 million metric tons of carbon dioxide each year.
These new numbers from volcanic regions pale in comparison with the amount of carbon dioxide released by fossil fuel combustion annually an estimated 29.7 billion metric tons in 2007.
Nevertheless, a better understanding and quantification of the amount of gas that volcanic regions put out "is still necessary for understanding global carbon budget modeling," said study researcher Nemesio Perez, a geochemist at the Technological Institute of Renewable Energy in Spain. "And having more precise information on the global carbon cycle and its implications on the present-day atmospheric carbon dioxide budget is important for the climate models."
The scientists detailed their findings in the March issue of the journal Geology. |
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