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An open standard for self-hosted RSS aggregator APIs.
1.9 KiB
Some API endpoints which are resource-intensive to handle are paginated. The following options are supported for paginated endpoints.
The limit query parameter may also be used with any of the following options (except Specific IDs) to specify the maximum number of resources to return. Default is 20.
Max ID
The max_id query parameter may be used to request resources immediately older than the given ID.
Min ID
The min_id query parameter may be used to request resources immediately newer than the given ID.
Since ID
The since_id query parameter may be used to request resources newer than the given ID.
Note: The since_id parameter does not return resources immediately newer, so using this may result in a gap. See the examples below for a comparison with the min_id parameter.
Specific IDs
Clients may request paginated resources with specific IDs.
The ids query parameter must be a comma-delimited string containing the numerical IDs for all the desired resources.
Server implementations may limit this endpoint to a maximum number of resources that may be requested at once. As such, clients should check that they received objects for all the IDs requested and perform another request if they haven't.
Given resources with IDs 1 through 50, all of which are accessible by the requesting user, these options will have the following results:
Resources with IDs 21 through 40 will be returned.
No resources will be returned.
Resources with IDs 10 through 29 will be returned.
No resources wil be returned.
Resources with IDs 1 through 19 will be returned.
Note that with this response, there is a gap between the ID requested in the parameter and the maximum ID returned by the server. Compare this with the result of the min_id=30 request above.
No resources will be returned.
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Astronomers have created 8 million universes inside the computer. And that's what they have learned
Despite the numerous assumptions that the universe - a computer simulation, in fact, the probability of this is very small. However, in the world, nothing is impossible, so scientists may well observe the variety of life forms in millions of universes. In theory. In fact, astronomers have created eight million Universes on the computer. The fact that the simulation of the origin and further development of the universe can tell a lot about our own.
The greatest mystery of the universe
If every time you think about the universe and that she like, you think that you know nothing about and do not understand what's really going on - this is normal. Our brain is extremely difficult to comprehend concepts such as infinity, laniakea supercluster and the event horizon of a black hole. And when it comes to dark matter and did get the feeling that the dark matter - the biggest mystery of our universe.
laniakea supercluster - supercluster of galaxies. Translated from Hawaiian word meaning "vast heavens."
At least scientists now adhere precisely this point of view. The goal of researchers to create 8 million computer simulations of the universe was the desire to understand the role played by this mysterious substance in the life of our Universe since the Big Bang.
Laniakei diameter approximately equal to 520 million light years
It is believed that shortly after the birth of the universe, invisible and elusive substance poluchivshae called "dark matter", using the force of gravity was transformed into a massive cloud, known as dark matter halo. As soon as a halo increased in size, they are attracted by the rare hydrogen gas that pervades the universe, to come together and form stars and galaxies that we see today. In this theory, dark matter acts as the foundation of galaxies by determining the formation, consolidation and development over time. Read about other mysteries of the universe on our channel in Yandex. Zen
To better understand the impact on the formation of the universe had a dark matter, scientists from the University of Arizona have created their own universe, using a supercomputer. 2000 processor to run without interruption for three weeks, simulating more than 8 million unique universes. Surprising is that each universe is subordinate to a unique set of rules to help researchers understand the relationship between dark matter and the evolution of galaxies.
The greatest computer simulations
The study is published in the journal Monthly Notices of the Royal Astronomical Society and is the first in its field. Previously, scientists have created a simulation unit, which focused on the modeling of individual galaxies. The new program is called Universe Machine. It continuously created universes millions, each of which contained 12 million galaxies. Moreover, all these millions of universes evolved from the Big Bang to the present day.
It may look like a computer simulation of the universe
According to experts the most interesting is that scientists can now use all the available data on the evolution of galaxies - their number, the number of stars and star-forming processes - and integrate them into a comprehensive picture of the past 13 billion years of the universe. It should be noted that the creation of an exact copy of our universe or galaxy would require incredible computing power. Therefore, scientists have focused on two key properties of galaxies: the total mass of stars and star formation rate. Join the discussion of this and other amazing discoveries of astronomy in our chat Telegram
According to the study, the rate of star formation in the galaxy of stars is closely related to the mass dark matter halos. In those galaxies where dark matter halo mass was like a dark matter halo of the Milky Way, star formation rate was the highest. This suggests that the more massive galaxies, the star is constrained by a large number of black holes.
The observations of astronomers have questioned the scientific assumptions about what dark matter is suppressed star formation in the early universe. In fact, smaller galaxies are more likely to form stars at a higher rate.
In the future, the researchers plan to expand the Universe Machine, to work out further variants in which the dark matter can affect the properties of galaxies, including the form of their development, the mass of black holes and the frequency conversion stars in supernovae.
Dizzily, is not it? Do you think you will be able to scientists to solve the greatest mysteries of the universe?
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Evidence Based Guideline: Management of Potential Inpatient Opioid Abuse and Diversion
Brief Description: The guideline aims to standardize patient care and empower the healthcare team in situations involving aberrant medication behaviors. Risk factors for aberrant behaviors are outlined along with preventative interventions to be used at clinician discretion or by RN per protocol.
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Octagon Inked Dinner Plate - Royal
$140.00 $102.00
From the eponymous studios of Paul Schneider Ceramics - come these delightful, saturated Inked Dinner Plates. The octagonal shape adds just the right amount of subtle chic to a plate that can day play as an everyday piece or dress itself up for the most glamorous occasions.
Made with a glorious drip glaze, typically reserved for his famous Lamps; Paul has recreated the same look on a smaller scale so you can enjoy his artistry in small doses too!
Dinner Plate - 11"
Dishwasher safe.
Note due to the hand made artistry each piece is unique and will be a variation of the depicted tray. Same color scheme - but brushwork is unique to each tray.
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Words Ending In X | Top Scrabble Words That End In X
A list of scrabble words ending with X A list of words that end with x for Scrabble that can also be used while playing Words With Friends. Here's a list of words that end with x of all different lengths.
X is not a Scrabble word.
The highest scoring words ending with X
Want to go straight to the words that will get you the best score? Here are all the highest scoring words with x, not including the 50-point bonus if they use seven letters.
Top words ending with XScrabble PointsWords With Friends Points
331 Scrabble words ending with x
4 Letter Words That End in X
3 Letter Words That End in X
2 Letter Words That End in X
FAQ on words ending with X
What are the best Scrabble words ending with X?
The highest scoring Scrabble word ending with X is Jukebox, which is worth at least 27 points without any bonuses. The next best word ending with X is fowlpox, which is worth 22 points. Other high score words ending with X are packwax (25), pharynx (22), pemphix (23), workbox (23), outjinx (21), kickbox (26), and lockbox (22).
How many words end in X?
There are 331 words that end with X in the Scrabble dictionary. Of those 68 are 8 letter words, 84 are 7 letter words, 71 are 6 letter words, 50 are 5 letter words, 24 are 4 letter words, 31 are 3 letter words, and 3 are 2 letter words.
How many two letter words end with X?
There are 3 two letter words that end with the letter X. They are ax, ex, and ox.
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Watch What Would Happen If Juliet Capulet Had A Sassy Gay Friend! (Video)
Werll we saw how things would be different if Ophelia would have had a Sassy Gay Friend in Hamlet. Now lets see how literary history would have changed if Juliet Capulet had a Sassy Gay Friend!
About Will Kohler
What do you think?
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The Dynasty Of Chinese History Essay
1715 Words7 Pages
The Six Dynasty period in Chinese historiography is often classified with moments of conflict, revolt, strife, famine, disunity, and not innovation. Historians and academics categorize the period as a placeholder between the more significant Han China—206 BCE to 220 CE—and the Tang dynasty—618 to 907 CE. Understandably, Han China’s military, infrastructure, and civil capabilities were rivalled only by that of the Roman Empire, and even then, the Han dynasties administrative capabilities were rivalled by none. The Tang period is widely considered to be the high point of Chinese culture and civilization, where cosmopolitan China emerged with force vastly shaping China for centuries to come. The significance of the Han and Tang dynasties is not in question, it is the lack of importance that historians confer on the Six Dynasties period. Admittedly the Six Dynasty period in Chinese history can be categorized as a warring period, in which China did not develop unilaterally, but separately along fractured lines (split both north-south, and east-west). Much like the European medieval period, there are few accessible sources from early-medieval china, and because of this, China’s six dynasty period is brushed over as a period of little advancement and innovation. The “Dark Ages” in Europe use to receive the same scholarly interpretation as a period of stagnation.
Agreeably a topic of righting historical wrongs is too large for too few pages, as such, the scope of this paper is not
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The Hunger Games By Suzanne Collins Essay
1475 Words6 Pages
Identity. Something so elementary to define, yet so onerous to apply to a person. Seemingly, it appears that only through experience someone can manage to partially grasp their identity as they are pushed to confront their environments and respond in an appropriate manner constitutionalized by their identity. In Suzanne Collins’ The Hunger Games, a novel set in Panem--a dystopian country that was originally North America before the outset of natural disasters, storms, fires, encroaching seas and war--follows the first person point of view of Katniss Everdeen (Collins 18). The totalitarian government, usually referred as the Capitol, subjects all of the twelve districts to select two male and female teenagers to participate in the Hunger Games, where the twenty-four tributes fight to the death in a gladiator style that is used to entertain the Capitol’s audience while reaffirming their dominance over the districts. Once Katniss’ sister, Prim, is randomly selected for the Games, Katniss quickly volunteers to take her place and she departs for the Capitol with the other tribute, Peeta Mellark. During Katniss’ time in the arena, she is forced to adapt to her horrid situation and recognize her genuine identity as she balances survival against humanity. As the story of Katniss develops throughout The Hunger Games, she is forced to acknowledge her authentic identity as she diverges from her initial preconception of her identity as she survives the new environment.
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4 Cheap Horse Stall Ideas: Enjoy Better Value With a Smaller Budget
Ideas for Building an Affordable Stable
Building a horse stable accrues horse-owners some pretty attractive perks. It puts them close to their equine best friend, making monitoring and training seamless, and allowing them to skip expensive horse boarding costs. All horse owners want to provide the best comfort and care for their companions. The good news is that you don't have to spend excessive amounts to provide a top-quality shelter for horses. Keep reading to learn how to build a budget-friendly stable on your horse property.
Choose Your Location and Measure Your Stable Space
To build a budget-friendly stable, you'll need to choose the location first. It should be close enough to, or if possible, on your property. This offers convenience and helps increase the time spent with your equine friend.
Setting a barn on your property also offers peace of mind, knowing that you can always look out the window to check on the horse. The topography of the location you choose for the barn also matters. The type of soil on the land you build the barn on can directly impact your horse's strength and overall health.
Also, some locations might be flood-prone or have high winds that may damage the roof and other parts of the stable, consequently endangering the horse and leaving you with high repair costs. When planning for horses in your community, brush up on real estate zoning laws since some neighborhoods limit the type of animals one can have on a property, even where owners can set up a horse stable on a lot. Remember, the type of topsoil and water around a horse stable can impact your horse's strength and overall health.
So, ensure the location you select has horse-friendly land. And to maintain cost-effectiveness, the stable site should be well-leveled and drained to prevent flooding. Once you find the ideal place, consider space requirements. An average horse needs at least 12ftx12ft of space to comfortably move around and lie fully reclined without touching the stable's walls.
Space requirements will differ for horse owners with multiple or bigger horses, such as drafts, or smaller breeds like the pony. One also needs to create room for hay and tack storage, feeding stalls, and grooming areas to achieve a budget-friendly but fully-functional DIY horse stable.
Select a Stable Style
Horse stables aren't one-size-fits-all. They're majorly categorized as either traditional or barn-style stables. Traditional stables are typically expensive to set up, so opt for simple designs such as a run-in shed. With only three sides and an open front, a run-in shed is easy and affordable to set up, especially for those with few horses. It provides enough space for the animal to move around, and the open design allows the horse's outdoor views to satisfy its observant nature.
Another great DIY horse stable design to consider is the shedrow. It features a row of horse stalls opening to the outdoors and has a smaller profile; hence it requires less space, plus it's easier and cost-effective to set up. Like the run-in shed, it also offers horses a view of the outdoors and provides endless design variations, such as U- and L-shaped sheds.
For multiple horses, consider a round horse shelter. You can design it in such a way that each stall has an exterior door offering direct access to the outdoors and an adjoining feeding stall designed as an open paddock. This leaves the center space room for hay, storage, or working space. Since there are no corners to hide in, the horses see each other, preventing loneliness. Alternatively, you could opt for a modular stable, which you build in a workshop, and assemble at the chosen location.
Gather Materials For Your Stable
How to Make a Horse Stable AffordablyWith the location, space, and horse style worked out, gather materials in preparation for building. Depending on the design, you will need wood, stone, or steel for the walls. If you opt for wood, get 4x4 posts, a post-hole digger, and cement to anchor them into the ground. You'll also need metal for the roof, plywood, siding, nails, and plywood.
Note, materials are where the costs of building a stable shoot through the roof, so you might want to be careful while weighing the options. For instance, opt for wooden instead of metal siding. Wooden siding is more economical, and while not the most durable, it can be pressure treated to enhance durability.
Choose shingle roofs as they're one of the most affordable popular roofing materials for buildings. Look for free building materials on sites like Facebook Marketplace or Craigslist, or check out building reuse centers as they often offer quality, recovered building materials at affordable rates. Another great source of cheap building materials for your barn is demolition listings. Alternatively, consider buying from one retailer. Once you determine the exact materials, you need to buy all your materials from one retailer to get a discount or affordable rates on each item.
Stick to the Essentials For Your Stable
As a horse-loving owner, it can be tempting to set up extras or implement luxury upgrades that maximize your horse's comfort. While there's nothing wrong with that, it'll only drive your costs up. So to stay on budget, stick to the essentials—that is, a stable with a feeding area, non-slip and durable base flooring, a tack room, and feed and hay storage areas.
Include a small wash stall with a suitable drain system to ensure you can groom your horse regardless of outdoor weather. It should also feature high-pitched ceilings and proper ventilation, so the strong ammonia stink from horse urine doesn't become a headache. In a nutshell, ensure the stable features all the horse needs for comfort.
Ready To Build Your Budget-Friendly Stable?
Horses make lovely companions. They're intelligent, have a longer lifespan than most animals, are energetic, and regular riding can be stress alleviating for humans and horses alike. However, they can be pretty expensive to maintain.
In addition to making necessary upgrades to your property, building a budget-friendly horse stable is one way to reduce these costs while ensuring the well-being of your equine friend.
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LED Full Form | What is an LED? Working, Advantages, and Disadvantages
LED Full Form
This write-up aims to impart information on the LED and LED full Form. After going through this write-up, you will know what LED stands for and the meaning of LED.
Further, explore the working of LEDs and how are they different from LCDs.
For a better understanding of the topic, we have commented on the safety of LEDs and included its advantages and disadvantages as well.
LED TVs or bulbs have become a part of lives over the past few years. The growing demands and use of LEDs can be noticed significantly. However, how much do you know about LEDs?
Must Read :- What is Electric Current?
What is the full form of the LED?
LED is used as an abbreviation for Light Emitting Diode.
What is an LED?
For many years, light-emitting diodes have been used as an essential element in electronics. It has gained its popularity owing to the several benefits it offers.
LED is a two-lead semiconductor light source that emits bright light on the passage of electricity through it.
The PN-junction diode emits light when activated. It is used in several electronic devices and equipment such as televisions, calculators, radios, watches, and more.
When compared to the conventional fluorescent light sources and lighting bulbs, it is 80% energy efficient.
Alongside this, it is a revolutionary product in the light source field owing to its effectiveness, longevity, and economical approach.
Also Read:- ITI Full Form
How LED works?
LED is a PN junction of a specialized form that takes into use a compound junction. The junction material must be a compound semiconductor.
A forward-biased diode, where electrons and holes are zipping back and forth across the junction, they constantly combine and wipe others out.
The electrons move from n-type into the p-type silicon and combine with a hole and disappear.
This makes an atom complete and stable and gives off a burst of energy in the form of tiny “packet” or photon of light.
What is the difference between LED and LCD?
It is important to understand the difference between LED and LCD as they are often related and confused.
We have listed below the difference between LED and LCD for you to understand.
Basis of ComparisonLED LCD
Full formLED is the acronym for Light Emitting Diode. LCD is the acronym for Liquid Crystal Display.
Lights usedIt uses light-emitting diodes It uses fluorescent lights
RelationAll LEDs are a subset of LCDs All LCDs are not a subset of LEDs
PlacementLEDs are usually placed behind the screens and around the edges. LCD is usually placed behind the screen
Size and efficiencyThinner in sizeMore energy efficient Thicker in sizeLacks energy efficiency when compared to LEDs
What are the advantages of an LED?
As compared to incandescent light bulbs, LED emits more lumens per watt.
LED light fixture efficiency is not affected by the shape and size which is the case with fluorescent light bulbs or tubes.
Size and colour
LED are available in very small sizes as well. They can easily be attached to printed circuit boards.
Moreover, they can emit light of an intended colour without the use of any colour filters.
Turn on and off timing
LEDs light up very quickly when the switch is turned on. They can achieve full brightness in under a microsecond and in communication devices they have a faster response time.
Cool lighting
Light-emitting diodes radiate very little heat in the form of IR that can cause damage to fabrics or sensitive object.
Long lifetime
When compared to fluorescent tubes, LEDs have a longer lifespan.
They have an estimate of 35000 to 50000 hours of useful life as compared to 10000 to 15000 hours of fluorescent tubes.
Things to Know:- NASA Full Form
What are the disadvantages of an LED?
When compared to a traditional light source, LED lighting is a more expensive investment.
Contrary to the several benefits it offers, it can be a high-cost purchase to be done.
The quality of LED lights is highly dependent on the operating temperature of the ambience.
High temperatures can change the parameters of the current passing through the semiconductor element. This can lead to burning out of the LED module.
Colour shift
There is a problem of colours shift which happens over time. Continuous UV exposure can cause the bulb to change its colour.
LED requires a voltage above the threshold and a current below the rating.
Dropping of efficiency
Along with the increase in the electric current, the efficiency of the LEDs decreases.
At higher currents, heating also increases which affects the lifetime of LED.
Heat emitting capacity
LED does not give off much heat when compared to the traditional electrical lights.
Therefore, when used in winter conditions for traffic control, it can have snow obscuring them.
Other Popular Posts from Author:-
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Desserts, Imma's recipes
Muffin-Chocolate Chip Cookies Filled with Oreo Cookies and Flavoured with Balsamic Vinegar of Modena IPG
Ingredients for 12 servings
250g flour
1/2 teaspoon baking soda
1/2 teaspoon salt
1 teaspoon of Balsamic Vinegar of Modena IPG
100g softened butter
100g dark brown sugar
100g white sugar
1 teaspoon of vanilla extract
1 whole egg
150g bitter chocolate drops
12 Oreo cookies
Author: Imma Di Domenico
In a bowl mix with the electric beater the butter, dark brown sugar and the white sugar Add the vanilla extract, the egg, the balsamic vinegar and mix again. Add to the flour the salt and baking powder, and then add the mixture to the dough. Mix again with the electric beater. When ready, add the chocolate drops using a wooden spoon. Let the dough rest in the refrigerator for about twenty minutes. In the meantime, heat up the oven at 170°C and put the muffin cups inside the muffin tin. As soon as the dough is cold (or at least cool), using two small spoons or the ice cream scoop, shape the balls. Holding the ball on the palm of your hand, make an indent in the center of the ball and fit inside one Oreo cookie, then add more dough to form again the ball. Place the balls inside the muffin cups and cook for about 15 minutes, making sure that the cookies stay soft, as outside the oven and once they cool off they will harden.
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Registration Dossier
Diss Factsheets
Environmental fate & pathways
Endpoint summary
Administrative data
Description of key information
Additional information
Ethylene diamine is a liquid with moderate vapor pressure (13 hPa at 20 °C). A calculated Henrys law constant of 0,6 Pa*m3/mole, giving a partitioning coefficient air/water of 3.2*10-3at temperature 25°C implies that volatilisation from water is low.
The substance has a very low octanol-water partition coefficient (log Kow = -1.6), which also indicates a low potential for uptake in aquatic organisms. The amino groups in Ethylenediamine will occur as charged species (cationic) under pH conditions encountered in the environment. Based on an adsorption study ethylenediamine is likely to sorb strongly to soil. The adsorption potential is more related to the cation-exchange capacity of the soil, than the organic content.
The substance is not susceptible to hydrolysis or direct photolysis in the aquatic environment. Biodegradation is the dominant process affecting fate of this substance in the environment
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deed: Meaning and Definition of
Pronunciation: (dēd), [key]
— n.
1. something that is done, performed, or accomplished; an act: Do a good deed every day.
2. an exploit or achievement; feat: brave deeds.
3. Often,an act or gesture, esp. as illustrative of intentions, one's character, or the like: Her deeds speak for themselves.
4. a writing or document executed under seal and delivered to effect a conveyance, esp. of real estate.
1. to convey or transfer by deed.
See also:
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The Founding of the Second Saudi State
This scarce map documents a series of battles that occurred during the Nejd Rebellion, which persisted from 1821 to 1824 and was fought between Egyptian forces and adherents to the Wahhabi movement on the Arabian peninsula. This movement was responsible for the rise of the House of Saud starting at the end of the 18th century, and this conflict would result in the Emirate of Nejd, also known as the Second Saudi State.
The map shows the region between Taif, just east of Mecca, down through Tabab, and slightly into northwesternmost Yemen. The path of military leaders is shown and demarcated and notes relay troop movements between 1824 and 1825. Topography is shown along the regions in which Ritter was able to gather data, and a number of towns and geographical features are shown.
In the lower part of the map, a number of insets show early pictorial figures and drawings made on cliff faces and cave walls from Yemen. The outside of two caves holding a sepulcher and a floor plan of this tomb is also shown. Yemen and the part of Saudi Arabia shown are renowned for their abundance of early historical artefacts, and Ritter was fascinated by this part of the region's history.
This was published by the eminent German historian, Carl Ritter, in the first half of the 19th-century. Carl Ritter is considered one of the founders of modern geography and was an important figure of his time. One of Ritter's best-known works, his Erdkunde im Verhaltnis. . ., attempted to describe the geography of the entire globe. This work had a very broad concept of geography, not only encompassing cartography but also hydrography, climatology, and volcanology. Ritter never completed his work due to the vast scale of his undertaking.
Condition Description
Even toning. Very faint fold wear. Library sticker in upper left.
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Bayesian filtering is a method for solving optimal filtering problems using Bayesian probability theory to estimate the state of a time-varying process or system which is observed through a noise-polluted signal. The state of a system refers to a collection of parameters which describe the behavior of a system. In Bayesian filtering problems, the state of the system is typically modeled as a Markovian chain with associated transition probabilities between states (see Appendix A).
Bayesian filtering is essentially a statistical inversion problem where a desired vector x must be estimated based on an observed signal y which is the summation of vector x with added noise. The goal is to use the observed sequence to produce an estimation of the hidden states. To do this in the Bayesian sense, this simply implies that the joint posterior PDF of all states given all observations must be computed,
p(\textbf{x}_{k}|\textbf{y}_{1:k}) = \frac{p(y_{k}|x_{k})p(x_{k}|y_{1:k-1})}{Z_{k}} (eq. 1.1)
p(x_{k}|y_{1:k-1}) is the predictive distribution of the state of \mathbf{x} at time interval k, which can be calculated using the Chapman-Kolmogorov in eq. 1.2. p(\mathbf{y}_{k}|\mathbf{x}_{k}) is the likelihood model for the observed sequence given \mathbf{x}, and Z_{k} is the normalization factor. Using eq. 1.1, Bayesian filtering problems compute the marginal posterior PDF of state \mathbf{x} at each time interval k given the previous history of observations up to time k. Application which apply Bayesian theory, such as Kalman filters, can be implemented using the following procedure:
1. Initialization: Assume an initial state from the given prior distribution p(\mathbf{x}_{0})
2. Prediction: The predictive distribution of the state of x is calculated as follows.
p(\mathbf{x}_{k}|\mathbf{y}_{1:k-1}) = \int p(\mathbf{x}_{k}|\mathbf{x}_{k-1})p(\mathbf{x}_{k-1}|\mathbf{y}_{1:k-1})d\mathbf{x}_{k} (eq. 1.2)
3. Update: From measurement \mathbf{y}_{k} at time interval k, the posterior PDF is calculated using eq 1.1, where the normalization constant can be calculated as:
Z_{k} = \int p(\mathbf{y}_k|\mathbf{x}_k)p(\mathbf{x}_{k}|\mathbf{y}_{1:k-1})d\mathbf{x}_{k} (eq. 1.3)
Appendix A: Markovian Chains
Hidden Markov models (HMMs) are statistical-based models which can be used to prototype the behavior of non-stationary signal processes such as time-varying image sequences, music signals, and speech signals. Non-stationary characteristics of speech signals include two main categories: variations in spectral composition and variations in articulation rate. An HMM considers the probabilities associated with state observations and state transitions to model these variations.
Consider the speech signal as shown in Figure 1 below. The respective segments of the given signal can be modeled by a Markovian state. Each state must consider the random variations that can occur in the different realizations of the signal by having probabilistic events which represent the state observation probabilities. The transition probabilities between each state provide a connection between the HMM states. When a given probabilistic event occurs, the state will transition to the next state in the HMM. Conversely, the state may self-loop rather than transition if a different probabilistic event occurs which does not imply transition.
markovian chain diagram
Figure 1: HMM speech model example
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Summertime scorcher heading to Finland
In the next few days temperatures will soar to 30 degrees in the north. Next week, it will be the turn of the rest of Finland to bask in tropical conditions.
Image: Suvi Turunen / Yle
Mixed weather is looming for Finland over the next few days. Parts of Lapland are bracing for temperatures reaching a sizzling 30 degrees Celsius, while northern Finland can expect a chance of showers with a side of thunder.
According to the Finnish Metereological Institute, FMI, Lapland has been issued a rare heat warning as temperatures may spike to uncomfortable levels. The yellow warning is issued when temperatures rise above 27 degrees with an average of over 20 degrees.
Dangerous conditions, which give rise to an orange warning, are flagged when daytime highs rise above 30 degrees and average over 24 degrees. On Wednesday, 31 degrees was recorded in the northern town of Sodankylä but FMI predicts the 30-degree marker could be broken again in the next few days.
Story continues after image.
Image: Yle Grafiikka
Meanwhile in southern parts of the country overcast skies are in the offing, with fickle rain clouds moving along the western border in the following days. The weather however will turn towards favourable conditions once more in the south and west as scorching temperatures are on the horizon for the weekend.
”Friday’s air mass is quite warm so where it is not raining and the sun is shining, we’re looking at temperatures around 25 degrees,” said Yle metereologist Joonas Koskela.
FMI predicts the balmy blanket will envelop the country for the week and possibly longer. The most blistering highs will be felt in central and northern areas, while southern Finland will be looking at overcast skies with temperatures in the twenties. Warmer conditions are not out of the question as FMI say busting the 30-degree mark is also possible.
Image: Yle Grafiikka
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these say the most
dundrum bridge form
Here's an opposite view. The bridge in Dundrum creeps towards the village.
Check the Dundrum section.
get a larger image
copyright 2001-2002
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Taino Lifestyle
Each society was a small kingdom and the leader was called a cacique. The cacique’s function was to keep the welfare of the village by assigning daily work and making sure everyone got an equal share. The relatives of the caciques lived together in large houses in the center of the village. These houses reflect the warmth of the climate and simply used mud, straw and palm leaves. The houses did not contain much furniture. People slept in cotton hammocks or simply on mats of banana leaves. The general population lived in large circular buildings called bohios, constructed with wooden poles, woven straw, and palm leaves.
At the time of Columbus there were five different kingdoms on the island of Hispaniola. The Indians practiced polygamy. Most men had 2 or 3 wives, but the caciques had as many as 30. It was a great honor for a woman to be married to a cacique. Not only did she enjoy a materially superior lifestyle, but her children were held in high esteem.
The Arawak/Taino used two primary architectural styles for their homes. The general population lived in circular buildings with poles providing the primary support and these were covered with woven straw and palm leaves. They were somewhat like North American teepees except rather than being covered with skins they needed to reflect the warmth of the climate and simply used straw and palm leaves.
The caciques were singled out for unique housing. Their house were rectangular and even featured a small porch. Despite the difference in shape, and the considerably larger buildings, the same materials were used. When the Africans came beginning in 1507 they introduced mud and wattle as primary building materials. However, there is no record of the Arawak/Tainos having used these materials.
The house of the cacique contained only his own family. However, given the number of wives he might have, this constituted a huge family. The round houses of the common people were also large. Each one had about 10-15 men and their whole families. Thus any Arawak/Taino home might house a hundred people.
The houses did not contain much furniture. People slept in cotton hammocks or simply on mats of banana leaves. They also made wooden chairs with woven seats, couches and built cradles for their children.
In addition to houses the typical Arawak/Taino village contained a flat court in the center of the village which was used for ball games and various festivals, both religious and secular. Houses were around this court. This was a hierarchical society, and while there was only one cacique who was paid a tribute (tax) to oversee the village, there were other levels of sub-caciques, who were not paid, but did hold positions of honor. They were liable for various services to the village and cacique.
Stone making was especially developed among the Arawak/Tainos, but they seem not to have used it at all in building houses. It was primarily used for tools and especially religious artifacts.
The men were generally naked, but the women sometimes wore short skirts. Men and women alike adorned their bodies with paint and shells and other decorations.
The Arawak/Taino diet, like ours, centered around meat or fish as the primary source of protein. There never were many wild animals to hunt on Hispaniola, but there were some small mammals which were hunted and enjoyed. They also ate snakes, various rodents, bats, worms, birds, in general any living things they could find with the exception of humans. They were able to hunt ducks and turtles in the lakes and sea. The costal natives relied heavily on fishing, and tended to eat their fish either raw or only partially cooked. Since they did grow cotton on the island, the natives had fishing nets made of cotton. The natives of the interior relied more on agriculture and de-emphasized meat or fish in their diet.
The Taino had a developed system of agriculture which was environmentally friendly and almost maintenance free. They raised their crops in a conuco, a large mound which was devised especially for farming. They packed the conuco with leaves which improved drainage and protected it from soil erosion. One of the primary crops cultivated by the Taino was cassava or yuca, which they ate as a flat bread. They also grew corn, squash, beans, peppers, sweet potatoes, yams, peanuts as well as tobacco.
(As an aside I would like to comment that many people in the pre-Columbian Americas had virtually work free agriculture. This system meant that people living in these materially simple social systems had enormous amounts of free time and often developed elaborate religious rites which took a lot of their time, but also had highly developed systems of games and recreation. There are some nice advantages to very simple living and diet!)
One of the Arawak/Taino’s primary crops was cassava. This is a root crop from which a poisonous juice must be squeezed. Then it is baked into a bread like slab. The current method of doing this in Haiti produces a flat bread, sort of like a stale burrito or pizza shell. The Arawak/Taino grew corn (maize), squash, beans, peppers, sweet potatoes, yams and peanuts.
They not only had cotton, but they raised tobacco and enjoyed smoking very much. It was not only a part of their social life, but was used in religious ceremonies too.
The Arawak/Taino had no large animals like horses, oxen or mules to ride or use for work. But they did have river and sea transportation. They used dugout canoes which were cut from a single tree trunk and used with paddles. They could take 70-80 people in a single canoe and even used them for long travels on the sea. These dugouts allowed fishing the few lakes of Hispaniola as well as fishing out a bit off the coast.
The Arawak/Taino themselves were quite peaceful people, but they did have to defend themselves from the Caribs who were cannibals. The Caribs of this area were centered at what is today Puerto Rico, but some did live in northeast Hispaniola, an area that today is the Dominican Republic. The Caribs were war-like cannibals. They often raided the more peaceful Arawak/Tainos, killing off the men, stealing and holding the women for breeding, and fattening the children to eat.
Thus the Arawak/Taino had some weapons which they used in defense. They used the bow and arrow, and had developed some poisons for their arrow tips. They had cotton ropes for defensive purposes and some spears with fish hooks on the end. Since there were hardwoods on the island, they did have a war club made of macana. This was about 1″ thick and reminds one very much of the cocomaque stick used in later Haitian days. They did not develop any armor or specifically defensive weapons (shields, etc.).
There were three primary religious practices:
• Religious worship and obeisance to the zemi themselves
There is a great debate as to just how many Arawak/Taino inhabited Hispaniola when Columbus landed in 1492. Some of the early Spanish historian/observers claimed there were as many as 3,000,000 to 4,000,000. These numbers seem to be based on very little reliable evidence and are thought to be gross exaggerations. However, since nothing like a census was done, the methods for estimating the numbers are extremely shaky, whether by these early historians or later critics.
Disease was a major cause of their demise. However, on Columbus’ 2nd voyage he began to require a tribute from the Arawak/Tainos. They were expected to yield a certain quantity of gold per capita. Failing that each adult of 14 was required to submit 25lbs. of cotton. For those who could not produce the cotton either, there was a service requirement for them to work for the Spanish. This set the stage for a system of assigning the Arawak/Taino to Spanish settlers as effective slave labor. This system contributed significantly to their genocide.
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This is Ann Rudegeair’s music collection on Bandcamp.
Ann Rudegeair
1. Jazz
1. collection 6
2. following 2
1. Nourse Mythology
by Adam Rudegeair
2. House Arrest
by Lake Minnetonka
3. The Bowie Project 2: It's Always Time
by The Bowie Project
4. Melbourneapolis
by Lake Minnetonka
5. 'Bourbon St to Brunswick St' - Live at the Paris Cat
by Adam Rudegeair and Bob Sedergreen
6. The Bowie Project
by Adam Rudegeair
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A No-Deal Brexit will also influence your temporary exportations to the United Kingdom!
Projects, fairs or demonstrations in the United Kingdom? Not without custom formalities!
In the absence of an agreement, the United Kingdom becomes an exporting country, just like the United States or China, where customs formalities apply. Both when leaving (exportation) or entering (importation) the UK. Specific customs procedures therefore apply when importing temporarily, participating in a trade fair, or exhibition maintaining machinery or demonstrating a prototype.
Are you looking for a simple solution? Then use an ATA carnet, a unique customs document that covers all stages of a temporary export. For more information, contact your Chamber of Commerce.
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Charlotte’s Blog
For expert tips and advice about caregiving.
Supporting you with information you need.
Everyone’s Cognitive Decline?
Not everyone has the genes to put them at risk for Alzheimer’s Disease. Not everyone has a lifestyle that could put them at risk for other forms of dementia or cognitive decline. But did you know that everyone’s diet…or more specifically, dietary deficiencies…can place them at risk for cognitive decline.
This is one of those cases where the data are impressive. Scientists have been following over 100,000 men and women (in comparable numbers) since the late 1970s and early 1980s. In the 2010s they revisited these individuals a series of seven surveys of diet and health. Ironically, the foods that may be most delightful in the colors they add to a culinary presentation are also the ones that can most give a boost to everyone’s brain power. The scientists found that flavonoids, the part of the plants biochemical make up that offers the colors that “pop” in the produce section of the store, are aggressive protection against the forgetfulness or confusion that often are associated with advancing age. This was not one of those studies that show what happens when one group was given flavonoids and the other wasn’t – an experimental design – but the research had a large enough sample and followed these 100,000 people for a long enough time to offer a strong foundation for conclusions. In short, what we eat can affect our brain’s cognitive health, and other scientists were sufficiently impressed that the research was published in the journal Neurology.
The specific elements that contributed to this “brain health” were part of what are termed flavonoids like the beta carotene in carrots or flavone in strawberries or anthocyanin in apples and other produce. The more flavonoids that people in the study consumed the less their cognition declined. (Flavonoids include flavonols, flavones, flavanones, flavan-3-ols, anthocyanins, polymeric flavonoids, and proanthocyanidins.) The beneficial foods extended beyond strawberries and carrots to include bananas, oranges, grapefruit, celery and peppers…basically look for a brightly colored vegetable or fruit, and you have a cognitive reward.
The positive impact of these foods included better short term memory or recall, ability to process and follow instructions, better engagement in group conversation, easier navigation of familiar places or just plain less forgetfulness or confusion. Pretty good reward for maintaining a healthy diet! The scientists go so far as to recommend starting the healthy diet as early as possible, because it is never too early to have a sharp brain. The downside? Well, the scientists found that some of our less favorite foods also are good for our brains: winter squash, raw spinach, onions and brussels sprouts. Perhaps this is a reminder that we should plan our meals with the less desirable vegetables to be followed by a healthy and tasty desserts with strawberries or apples or peaches?
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Thesis intro paragraph
Thesis intro paragraph
Repeats class discussion or other critics Unrelated to or contradicted by the text Unrelated or partial response to prompt Language is vague, wordy Getting Started: This list is not exhaustive; anything that helps you consider your text or subject in a complex, unusual, or in-depth manner will get you on the right track: Do I have a gut response to the prompt?
Create your Thesis Statement
What is the significance of this text or subject? Why did my professor choose it? How does it fit into the broader themes or goals of the course?
How does this text or subject relate to the broader context of the place or time period in which it was written or in which it occurred? Does this text or subject challenge or complicate my ideas about race, class, gender, or religion?
About political, carceral, or educational institutions?
Thesis intro paragraph
Introductory Paragraphs
See the following examples of weak or unfinished thesis statements: Setting is an important aspect of Wuthering Heights. Britain was stable between and Both examples are too broad.
Thesis intro paragraph
One way to develop them is to consider potential conjunctions that would help you complicate your ideas:The Introductory Paragraph. The paragraph that begins an essay causes students the most trouble, yet carries the most importance.
Although its precise construction varies from genre to genre (and from essay to essay), good introductory paragraphs generally accomplish the same tasks and follow a . The thesis is the essence of an argumentative essay. In a single, clear sentence, it sums up what point you are trying to make.
The thesis statement should assert a position on a particular issue -- one that a reader can potentially argue against. An introduction is the first paragraph of a written research paper, or the first thing you say in an oral presentation, or the first thing people see, hear, or experience about your project.
The opening paragraph of your paper will provide your readers with their initial impressions of your argument, your writing style, and the overall quality of your work. Your direct. Albrecht Dürer: The Genius with a Great Soul. Albrecht Dürer was not only the greatest artist of the Northern Renaissance, but also a unique personality, his genius coexisting with a pure, noble character.
Remember, it is an introduction, not the paper. from "Going, Going, GONE to the Auction!" by Laurie Goering in Chicago Tribune Magazine, July 4, Do not forget, though, that your introductory paragraph should also include a thesis statement to let your reader know what your topic is and what you are going to say about that topic.
What is introduction paragraph
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Support from FASE's Education Technology Office
I would like to create a mandatory survey for each student group to complete. How can I do this in Quercus?
Answer: To create a mandatory survey in Quercus, you'll want to create a new Quiz (type is survey), add it to a module, and add a requirement to the module so that students cannot proceed with the course until they've submitted the survey. You could also provide motivation to complete the survey by making it graded.
How to add a mandatory survey to your Quercus course
1. Create a new Quiz (type = survey) (see How do I create a new quiz/survey?)
2. Add your Quiz to a module (see How to time release assessments (using module requirements))
3. Add a requirement to your module (see How do I add a requirement?)
In Quercus, the Quizzes tool allows you to create two types of assessments:
1. Quiz - Used to test/check in on students' learning for summative and formative assessments.
2. Survey - Used to collect non-graded feedback from students. This is typically used to poll students for feedback and preferences. Note that while they can be semi-anonymous (student name is not attached to survey), you can see who completed and who did not; for a truly anonymous survey, we recommend using a Microsoft Form (see how do I create an anonymous survey?).
Still have questions? Contact the FASE EdTech Office
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TY - JOUR JF - iut-jame JO - jame VL - 19 IS - 1 PY - 2000 Y1 - 2000/7/01 TI - Optimum Design of Sewer Collection Networks TT - طرح بهینه شبکه های جمع آوری فاضلاب N2 - Various methods have been used to economically design wastewater and stormwater collection systems. In this article, Discrete Differential Dynamic Programming (DDDP) which is a subsection of dynamic programming (DP) was used. For each pipe network, various alternatives such as depth and slope of pipe laying and various diameters could be considered to satisfy hydraulic and engineering constraints. From an economic viewpoint, however there are few alternatives to minimize the costs. Planning algorithm for DDDP is based on determination of one initial answer for network and modifying the answers in continous trials which satisfy economic and engineering considerations. To limit the range of answers in each trial, a corridor of solutions was defined. This range in each trial will converge to an optimum solution. In this regard, a computer program called SNOP (Sewer Network Optimization) has been developed. Several design examples have been run with this program. The results show the suitability of the program. SP - 199 EP - 208 AU - N. Talebbeydokhti and R. V. Rohani, AD - KW - - UR - http://jame.iut.ac.ir/article-1-191-en.html ER -
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Is weather a noun verb or adjective?
Is weather a noun?
Weather is an uncountable noun: We had nice weather on Monday for our trip to the coast.
Can weather be verbs?
Verb The wood on the porch has weathered over the years. They weathered a terrible storm while at sea. He has weathered the criticism well. These example sentences are selected automatically from various online news sources to reflect current usage of the word ‘weather.
What type of verb is weather?
1[intransitive, transitive] to change, or make something change, color or shape because of the effect of the sun, rain, or wind This brick weathers to a warm pinkish-brown color. weather something Her face was weathered by the sun.
What is the adjective for weather?
Describing the weather
rainy, wet, humid, dry, arid, frigid, foggy, windy, stormy, breezy, windless, calm, still; a spell of good weather; a two-day spell of sunny weather; a spell of rainy weather; Sky: cloudy, overcast, cloudless, clear, bright, blue, gray (BrE grey), dark; a patch of blue sky.
Which part of speech is weather?
The term weather can be a noun or a verb.
What is noun example of noun?
A noun is a word that refers to a thing (book), a person (Betty Crocker), an animal (cat), a place (Omaha), a quality (softness), an idea (justice), or an action (yodeling). It’s usually a single word, but not always: cake, shoes, school bus, and time and a half are all nouns.
THIS IS INTERESTING: What do you do if you are Brainly during a tsunami?
What is the description of weather?
What is weather definition biology?
What is the sentence of weather?
The weather is unpredictable around here.” “We have severe weather during the winter.” “I hate living in cold weather.” “We can expect rainy weather tomorrow.”
Is the is a verb?
Yes, “is” is a linking verb. Linking verbs typically link subjects to descriptions.
What is weather in social?
Weather is the state of the atmosphere at any given time. … Weather has many aspects, including wind, pressure, cloud cover, temperature, and precipitation.
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The Carousel Builder allows you to visually build carousels using either a Repeater, Easy Posts, Products List, ACF gallery fields, or any elements as individual cells.
Scroll down to view some previews of various settings
Custom icons or any elements can be used as navigation arrows
(like these lottie arrows)
Carousels can be linked together. Clicking on one to control the other, useful for thumbnail navigation.
We can style the selected, previous & next cells dynamically with opacity & transform controls.
The ticker setting allows for continuous movement in either direction, useful for logos, social proof etc.
The Parallax Effects added on inner elements allows for adding depth as the elements move at different speeds.
'Contain' helps to keep things looking neat by ensuring the start/end points remain inline with the section wrap
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What is an advantageous trait that becomes more common in a population?
Natural selection is a process that causes heritable traits that are helpful for survival and reproduction to become more common, and harmful traits to become more rare. This occurs because organisms with advantageous traits pass on more copies of these heritable traits to the next generation.
Why are advantageous traits more likely to be passed onto offspring?
Q. Why are advantageous traits more likely to be passed onto offspring? Because they are more likely to survive and reproduce. Because they come from dominant alleles.
Why is genetic variation an advantage for a population?
Why do traits in populations change over time?
Evolution is a process that results in changes in the genetic material of a population over time. Evolution reflects the adaptations of organisms to their changing environments and can result in altered genes, novel traits, and new species. The study of evolution can be performed on different scales.
Which term best describes a change in the allele frequencies in a population?
Microevolution, or evolution on a small scale, is defined as a change in the frequency of gene variants, alleles, in a population over generations. The field of biology that studies allele frequencies in populations and how they change over time is called population genetics.
Which conditions are required for natural selection select three options?
How is natural selection different from artificial selection?
The difference between the two is that natural selection happens naturally, but selective breeding only occurs when humans intervene. For this reason selective breeding is sometimes called artificial selection.
cells are considered the basic units of life because a cell is the level at which the properties of life emerge. In other words, a cell is the lowest level of structure that can perform all activities required for life.
What name is given to a proposed explanation for a set of observations?
What does adaptation mean in biological context?
In evolutionary theory, adaptation is the biological mechanism by which organisms adjust to new environments or to changes in their current environment. Organisms can adapt to an environment in different ways. They can adapt biologically, meaning they alter body functions.
What is the name given to the reaction that breaks peptide bonds?
What is the most likely outcome for a person who produces insufficient lactase?
12.3. Lactose intolerance, also called lactase deficiency, is due to an insufficient level of lactase, which hydrolyzes lactose into glucose and galactose. Therefore, ingestion of milk and dairy products results in bloating, abdominal cramps, diarrhea, and related symptoms.
What is a protein’s function dependent on?
A protein’s overall function is dependent on the shape of it. This is determined by four structural levels. The primary structure of an enzyme is simply the sequence of amino acids. Wikipedia. The secondary structure represents how the peptide folds and twists on itself due to interactions between the amino acids.
How many monomers are in a protein?
Usually about 20 types of amino acid monomers are used to produce proteins.
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girlfriend Trivia Quizzes and Games
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Word Ladder: Superman's Women
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Lesson Fairly Fundamental Facts about Forces and Structures
(7 Ratings)
Quick Look
Grade Level: 7 (6-8)
Time Required: 45 minutes
Lesson Dependency: None
Subject Areas: Physical Science
A photograph shows two hands bending a rod.
Bending forces in action.
Copyright © 2000 WGBH Educational Foundation
Students are introduced to the five fundamental loads: compression, tension, shear, bending and torsion. They learn about the different kinds of stress each force exerts on objects.
Engineering Connection
Engineers take into consideration the impact of many types of forces when designing structures. Factors that influence the design decisions include: anticipated use of the structure, expected weather exposure, and the type of soil it will be built upon. Engineers choose the best materials and design approaches for buildings and machines by calculating how much, and what kind of stresses each material is able to withstand without failure.
Learning Objectives
After this lesson, students should be able to:
• Explain the concept of a moment and how to calculate one.
• Explain how moments create bending and torsion loads on structures
Educational Standards
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• Explain how the forces of tension, compression, torsion, bending, and shear affect the performance of bridges. (Grades 6 - 8) More Details
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• Identify appropriate materials, tools, and machines needed to construct a prototype of a given engineering design. (Grades 6 - 8) More Details
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More Curriculum Like This
Middle School Lesson
Investigating Torque
Students learn about torsion as a force acting upon structures and have the opportunity to design something to withstand this force.
High School Lesson
Doing the Math: Analysis of Forces in a Truss Bridge
Middle School Lesson
Strong as the Weakest Link
To introduce the two types of stress that materials undergo — compression and tension — students examine compressive and tensile forces and learn about bridges and skyscrapers. They construct their own building structure using marshmallows and spaghetti to see which structure can hold the most weigh...
High School Activity
Feel the Stress
Working individually or in groups, students explore the concept of stress (compression) through physical experience and math. They discover why it hurts more to poke themselves with mechanical pencil lead than with an eraser.
Have you ever wondered why skyscrapers don't fall over? Why bridges don't sink into the rivers they span, or why bicycles are different sizes and shapes? Why are some buildings made of wood and others are made of steel and glass? That's easy! Because they are made that way right?
Well, how do the people who design things know which material is best to use, how tall a building can be, or even where the best place is to put a bridge? Engineers design structures, such as buildings, dams, airplanes, automobiles, tunnels, chairs, bicycle frames and even toys to hold weight and withstand forces that are placed on them that could tear them apart. So what is a force?
We all know from experience that a force is the amount of pushing or pulling required to move an object. Engineers determine the loads or external forces that act upon a structure. When external forces are applied to a structure, internal stresses (internal forces) develop resistance to the outside forces. The opposition of external and internal forces is what holds the structure together. Once engineers know the loads acting on a structure, they calculate the resulting internal stresses, and design each piece of the structure so it is strong enough to carry the loads without breaking. Students can act as engineers by illustrating tension, compression and torsion in the Forces in Structures: Glue Sticks Bend & Twist activity.
Lesson Background and Concepts for Teachers
1. Tension: Two pulling (opposing) forces that stretch an object trying to pull it apart (for example, pulling on a rope, a car towing another car with a chain – the rope and the chain are in tension or are "being subjected to a tensile load").
A drawing of a beam with 2,000 lbs of force pulling it apart from each end. Inside, molecules are pulling back, trying to stay together and keep from being ripped apart.
Figure 1. Tension.
1. Compression: Two pushing (opposing) forces that squeeze an object trying to compress it (for example, standing on a soda can, squeezing a piece of wood in a vise – both the can and the wood are in compression or are "being subjected to a compressive load").
A drawing of a beam with 2,000 lbs of force pushing on a beam from opposite ends. Inside, molecules are pushing back, trying to stay apart and not get crushed.
Figure 2. Compression.
1. Shear: Two pushing or pulling adjacent forces, acting close together but not directly opposing each other. A shearing load cuts or rips an object by sliding its molecules apart sideways (for example, pruning shears cutting through a branch, paper-cutter cutting paper - the branch and paper are "subjected to a shear loading").
Figure 3. Shear.
Another example: Pulling on two pieces of wood that have been glued together; the glue joint is "being subjected to a shear loading."
Figure 4. Shear forces on glued wood.
A Moment of a Force
Understanding a moment of a force is key to understanding the last two types of loads. A moment is a "turning force" caused by a force acting on an object at some distance from a fixed point. Consider the diving board sketch in Figure 5. The heavier the person (force), and the farther they walk out on the board (distance), the greater the "turning force," which acts on the concrete foundation (fixed point).
Figure 5. Moment of a force.
Equation: M = F x d
Figure 6: Equation for a moment of a force.
(As long as the force acting on the object is perpendicular to the object.)
If a force measured in Newtons is multiplied by a distance in meters, then the units for the moment are N-m (read "Newton-meters"). If the force is measured in pounds and multiply by a distance in inches, then the units are be lb-in (read "pound-inches"). Units for moments can be any force unit multiplied by any distance unit.
1. Bending: When a moment or "turning force" is applied to a structural member that is fixed on both ends, such as a pole beam, making it deflect or bend. A moment that causes bending is called a bending moment. Bending produces tension and compression inside a beam or a pole, causing it to "smile." The molecules on the top of the smile get squeezed together, while the molecules on the bottom of the smile get stretched out. A beam or pole in bending will fail in tension (break on the side that is being pulled apart) (for example, a shelf in a bookcase, and the earlier diving board scenario).
Figure 7. A bookcase example of bending.
Figure 8. Torsion.
Associated Activities
Problem 2: If 1 N = 0.2248 lbf and 1m = 3.28 ft, convert the units in the previous problem to obtain a solution in Nm (Answer: 18,000 lbf-in. x 1 N / 0.2248 lbf x 1 ft / 12 in. x 1 m / 3.28 ft = . 203 Nm)
Other Related Information
Douglas Prime, Tufts University, Center for Engineering Educational Outreach
Supporting Program
K-12 Outreach Office, Worcester Polytechnic Institute
Last modified: January 20, 2022
User Comments & Tips
Find more at TeachEngineering.org
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Empowering customers to deploy
data-driven marketing strategies
Deep Analytics
Aggregate scattered data for a consolidated organic paid analysis and optimization. Spot and repeat campaign successes.
Deep Analytics
Customer Insights
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Provides data-driven analytics in various forms such as customer sentiments and intents.
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Deep dive into campaigns, with real-time data insights across profiles and platforms.
Real-Time Data Analytics
Monitor Campaign Performance
3. Monitor Campaign
Get updates on campaign performance and sentiment as it rolls out, allowing automation to save time.
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pixmorph — morph two pix(5) images
pixmorph [-w width] [-n height] picA.pix picB.pix linesfile warpfrac dissolvefrac > out.pix
pixmorph performs feature-based image metamorphosis between "picA.pix" and "picB.pix". The feature correspondences are specified in the file "linesfile", which can be created using a utility such as morphedit.tcl (see morphedit(1)).
The output image is computed in the following fashion. First, for each pixel in the output image, we choose a set A of pixels (and associated weights) from "picA.pix" and another set B of pixels from "picB.pix" (how these sets and weights are chosen will be described momentarily). The pixel values from A are then averaged (using the associated weights) to determine the contribution cA from the original image; the contribution cB is computed similarly. Then, the values cA and cB are interpolated by the value dissolvefrac to compute the final value of the output pixel.
Now, the contribution cA from the original image is intended to be the value from picA.pix that gets "warped to" the location in question. It is this computation (more specifically, the computation of A and associated weights) that is the heart of the morphing algorithm, and is described briefly here.
First, the linesfile is processed. The linesfile is of the form a b p n lineseg1_initial lineseg1_final lineseg2_initial lineseg2_final linesegn_initial linesegn_final , where n equals the number of line segments, and a, b, and p are constants that alter the nature of the morph. A line segment is represented as a list of four real numbers (and is interpreted as a directed line segment). For example, 0.1 2.0 0.2 2 0.714844 0.560547 0.988281 0.277344 0.347656 0.646484 0.654297 0.896484 0.341797 0.611328 0.757812 0.265625 0.628906 0.519531 0.925781 0.763672 is a valid lines file. Typically, the pairs linesegi_initial linesegi_final have been placed by the user in the lines file to match up particular features of picA.pix and picB.pix (the feature at linesegi_initial in picA.pix corresponds to the feature at linesegi_final in picB.pix). For instance, lineseg1_initial might be a line segment running down the length of the nose of a person displayed in picA.pix; then lineseg1_final would be a line segment running down the length of the nose of the person featured in picB.pix. See morphedit(1) for more information about creating a lines file.
Now, for each line segment pair (s,t), we perform the following procedure: We interpolate between s and t by factor warpfrac to yield the interpolated line segment s'. From the change in position, scale, and orientation of a line segment from its initial position s to its interpolated counterpart s' we may deduce a linear transformation in the image space. More specifically, if the line segment s must undergo translation, stretching, and rotation to yield s', we compute a linear transformation T of the image space that performs the same translation, stretching, and rotation. (So T applied to s yields s'.) The inverse T* of this transformation maps s' to s; for instance, T* will take an endpoint of s' to the corresponding endpoint of s, and will preserve the relationship of every other point to the line segment. We apply this inverse T* to the coordinates (x,y) to find an appropriate pixel in the original image. Along with this, we compute a weight based on the length of the line segment s along with its distance from (x,y). This weight is equal to ( (length ** p) / (a + dist) ) ** b (where ** denotes exponentiation, length is the length of s, dist is the distance from s to (x,y), and a, b, p are constants chosen by the user and stored in the lines file).
The set A of pixels is then collected by performing these computations for each line segment, and the resulting contribution cA is then computed by averaging over A with the appropriate weights.
In practice, a = 0.1, b = 2.0, and p = 0.2 seems to work well.
In general, the user will wish to set warpfrac = dissolvefrac. Typically, a morph animation will be produced by computing a sequence of images using pixmorph, each with slightly greater warpfrac (and dissolvefrac) (see the example). For a clearer and more thorough explanation, see T. Beier and S. Neely, Feature-Based Image Metamorphosis, "SIGGRAPH 1992 Computer Graphics Proceedings (volume 26 number 2)", (Chicago, July 26-31, 1992), pp 35-42, which presents the algorithm used by pixmorph.
Tells pixmorph that the input images have width WIDTH.
Tells pixmorph that the input images have height HEIGHT.
pixmorph face1.pix face2.pix lf 0.0 0.0 > frame0.pix
pixmorph face1.pix face2.pix lf 0.2 0.2 > frame1.pix
pixmorph face1.pix face2.pix lf 0.4 0.4 > frame2.pix
pixmorph face1.pix face2.pix lf 0.6 0.6 > frame3.pix
pixmorph face1.pix face2.pix lf 0.8 0.8 > frame4.pix
pixmorph face1.pix face2.pix lf 1.0 1.0 > frame5.pix
Note that the example above will result in frame0.pix = face1.pix and frame5.pix = face2.pix.
pixmorph face1.pix face2.pix lf 0.5 0.0 > out.pix
Note that in this example, dissolvefrac = 0. This will warp face1.pix and face2.pix by the appropriate amount, but will ignore the contributions of face2.pix at the cross-dissolve stage. So the final image out.pix will consist entirely of values from face1.pix warped 50% according to the linesfile lf.
pixmorph face1.pix face2.pix lf 0.0 0.5 > out.pix
In this example, warpfrac = 0. This will perform a simple 50% cross-dissolve between face1.pix and face2.pix.
brlcad(1), morphedit(1), pix(5)
This software is Copyright (c) 1996-2016 by the United States Government as represented by U.S. Army Research Laboratory.
Reports of bugs or problems should be submitted via electronic mail to <>.
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U.S. flag An official website of the United States government
Dot gov
Official websites use .gov
Secure .gov websites use HTTPS
A computer program that can copy itself and infect a computer without permission or knowledge of the user. A virus might corrupt or delete data on a computer, use e-mail programs to spread itself to other computers, or even erase everything on a hard disk. See malicious code.
CNSSI 4009-2015
NIST SP 800-12 Rev. 1 under Virus from CNSSI 4009
A program that replicates itself by attaching to other programs or files, where it hides until activated.
NIST SP 800-28 Version 2 under Virus
A hidden, self-replicating section of computer software, usually malicious logic, that propagates by infecting (i.e., inserting a copy of itself into and becoming part of) another program. A virus cannot run by itself; it requires that its host program be run to make the virus active.
NIST SP 800-82 Rev. 2 under Virus from RFC 4949
A computer program containing a malicious segment that attaches itself to an application program or other executable component.
NIST SP 800-47 [Superseded] under Virus
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Methods for cObject
View method list in alphabetical order
ClassSuperClassFunctionReturns the superclass of the passed class
CreateFunctionCreates an object based on the passed Class Id
CreateNamedFunctionCreates an object based on the passed Class Id and assigns it a name Name based on a passed name
DestroyProcedureDestroys the object that receives the message and any child objects of that object
Exit_ApplicationProcedureStarts the process of closing an application
IsClassOfClassFunctionDetermines whether the target class is part of the searched class's hierarchy
IsObjectOfClassFunctionDetermines whether the passed class is part of the object's class hierarchy
ObjectClassFunctionReturns the integer class ID assigned to the class this object is based on
Request_Destroy_ObjectProcedureUse the Destroy method instead [Obsolete]
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Adult Sex Chat With xAnneMarrie Webcam Model
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The symbol is a stylized cross that represents a circle and a star.
It is often used in religious texts.
According to the National Council of Churches, there are over 100,000 symbols in the U.S. The symbols are typically used to represent religious people, such as saints, saints, religious leaders, and holy persons.
The symbol also is used in schools and public spaces.
The word “scotson” is a reference to Scottsdale, Ariz., where the symbol is used.
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“Dancing in the Dissonance” – A Conflict Resolution Skills Activity
Designed by Audrey Williams
I. Introduction
The goal of the “Dancing in the Dissonance” activity is to introduce the concept of “dissonance” as a tool to build curiosity and respect for difference in shared meaning-making spaces. The activity draws on narrative and musical tools for conflict resolution to build a better understanding of how people make meaning both individually and as part of a group. By the end of the activity, participants should have a better appreciation for how curiosity, complexity, and difference relate to healthy experiences of conflict.
By working with a pre-selected song to make and share meaning around sonic representations of conflict, participants will have the chance to ponder how meaning making happens on multiple levels, including:
• on the level of the individual;
• on the level of the group; and
• on the level of the message between artist and audience.
This activity can be carried out in settings where participants already know each other as well as in settings where participants are just meeting each other for the first time. This activity involves a pre-class work expectation, and so it should be used in contexts where the facilitator has enough advance connection with participants to send pre-class materials to them.
At each stage, the activity is designed to help participants build greater appreciation for the flexibility and adaptability of meaning while also exercising their curiosity about how people can have different experiences of the same phenomena. Participants will learn how to see dissonance as an invitation to curiosity, and will walk away with an understanding of how to use curiosity to navigate difference in a generative, rather than destructive, way.
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Ap english scarlet letter questions
One girl wrote about a young woman going back and forth between two lovers—Hester unleashed. Anything that went against the Bible, such as adultery, was a crime and was treated as such. This is asking for TONE and evidence supporting your inference. Yet, at fifteen, they can still be reached.
She performs numerous acts of charity, but does so in isolation, receiving condemnation from the very souls she helps. At this point we can see Dimmesdale, without saying it, has a strong relationship with Hester.
She made the book possess them, so that, eventually, they would possess the book. Each want the most for each other, but have different ways of expressing it.
Free Teacher Resources
She can never fully know her father, she will forever know her mother only by the scarlet A sewn on her chest, and she will be forever branded as the product of sin.
In the final class on The Scarlet Letter, Mary Whittemore showed up wearing a twenty-dollar black Cher wig and holding a baby doll in her arms—the same baby doll that a student had held earlier.
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Why does the jailer call a doctor. What effect does the detailed description of the scarlet letter have on you. They wrote papers extending the narrative, in the voice of one or another of the characters.
Look thou to it. What canst thou do for the child in this kind…We will judge warily," said Bellingham, "and look well what we are about to do. Ye shall not take her. It was a return to the scaffold, where Hester had faced the jeering students.
The young minister, on ceasing to speak had withdrawn a few steps from the group, and stood with his face partially concealed in the heavy folds of the window-curtain; while the shadow of his figure, which the sunlight cast upon the floor, was tremulous with the vehemence of his appeal. The students responded to her, especially in those moments when she cast away mildness.
I study English to read technical English books. Speak thou, the child's own mother. What is the purpose of this chapter.
Give at least 2 reasons why Hester does not leave the colony. God gave her the child, and gave her, too, an instinctive knowledge of its nature and requirements--both seemingly so peculiar--which no other mortal being can possess.
She remains silent as to who her baby's father is, even when a mob of people is interrogating her. Pearl was the result of a sin.
Where can i find A.P English multiple choice questions on The Scarlet Letter?
In the end, the moral complexities of The Scarlet Letter made sense to them. Are we going to create three-dimensional men and women—and citizens—in this country. And poor Pearl is unfortunately caught in between all of this.
Yet she was extremely persistent, with hints of an underlying fire beneath the warmth and equanimity. She is my happiness--she is my torture, none the less.
Hester is a strong woman in the face of adversity. What is the purpose of this chapter.
The Scarlet Letter
The Scarlet Letter Multiple Choice Test Answer Key
On the breast of her gown, in fine red cloth, surrounded with an elaborate embroidery and fantastic flourishes of gold thread, appeared the letter A. Jane austen essay titles kitchen sink plumbing diagram, descriptive essay outline template cost of starting a greenhouseWhich lines from the love song of j alfred prufrock best express themes of alienation and isolation start your own business course online proposal format computer shortcut keys pdf warehouse proposal pdf freedom essay example purpose of attending college.
It is subtly revealed when in paragraph 6 when Hester is telling Dimmesdale to vouch for so she could keep Pearl. Verbal Irony — Dimmesdale refers to himself as the worst of sinners during his sermons. Getting students to read seriously lies at the heart of establishing judgment, critical thinking, empathy, and a future audience for literature—an active participation of readers and writers in the defining stories we tell one another.
How was this style created, and what is its effect on the reader. At this point we can see Dimmesdale, without saying it, has a strong relationship with Hester. The Scarlet Letter Study Questions Quotes of Note: “ he attached himself to him as a parishioner.” “Wherever there is a heart and an intellect, the diseases of the physical frame are tinged with the peculiarities of these.” “ the man of skill, the kind and friendly physician—strove to go deep into his patient’s bosom.
AP English English 3 AP English Ap Exam Resources Writing The Book Scarlet Letter test Scarlet Letter Quiz 1 Hawthorne facts pearl symbolic 3 Goodman Brown Quiz scarletletter penguin teacher guide scarlet letter and modern critics citizen hester The Scarlet Letter essay for advanced student discussion questions women reading writing and.
In addition to the scarlet letter, Pearl is another symbol of Hester’s sin. Pearl is described as being a defiant child, for example, when Hester attempts to teach Pearl about God, Pearl refuses to listen, and she constantly produces mischief.
Start studying The scarlet letter study guide questions for AP Language. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Scarlet Letter Ap Study Guide Document for Scarlet Letter Ap Study Guide is available in various format such as PDF, DOC and ePUB which you can directly download and save in in.
The Scarlet Letter TEST True/False (2 pts. each) Indicate whether the statement is true or false.
The Scarlet Letter: Study Questions and Answers
Identify the choice that best completes the statement or answers the question. ____ According to The Scarlet Letter, new settlements must establish at the beginning of the colony a.
Ap english scarlet letter questions
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AP English Language and Composition - Scarlet Letter
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Literature, in theory: tropes, subjectivities, responses, responsibilities
Julian Wolfreys
Research output: Book/ReportBook
This is a significant work of original thought - addressing the interface between literature and theory. In the interview that begins "Acts of Literature", Jacques Derrida responds to a question concerning the difference between literature and theory by arguing that despite its institutional status, part of its 'institution' is the right of literature to say anything. Additionally, "Literature" gathers into itself numerous traits of other discourses, other cultures and other histories: autobiographical, theoretical, linguistic, philosophical, economic, scientific and journalistic, amongst others. As a result, we might argue that literature cannot be defined as such, and as soon as one seeks to produce a reading of the literary, complications arise through the difference, as Derrida has it, 'between literatures', and 'between the literary and non-literary'. 'Theory', so-called, is also a matter of difference and differences. Despite its institutional significance, 'theory' remains something many wish would go away, and which, for others, is still not read, is misread, and remains to be read. In examining closely how 'theory' and 'literature' are concepts and names for what we barely perceive, but which touch on one other in complex ways, "Literature, in Theory", seeks to move, with patience and attentiveness, to the beginning of an understanding of their intersections and differences. Examining a wide range of authors, from Dickens to Joyce, and engaging directly with a number of major theorists - including Derrida, Miller, Bloom, Heidegger, Agamben - Wolfreys takes the reader on a journey through the issues and ideas involved in reading literature, in theory.
Original languageEnglish
Place of PublicationLondon
PublisherContinuum International Publishing
Number of pages306
ISBN (Print)9781441161529
Publication statusPublished - 2010
Dive into the research topics of 'Literature, in theory: tropes, subjectivities, responses, responsibilities'. Together they form a unique fingerprint.
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The Scottish Parliament has missed the opportunity to declare a nature emergency, after the SNP blocked the vote with an amendment congratulating the Scottish Government instead.If passed, the Scottish Green motion would have made Scotland the first country to formally recognise the rapid decline in species populations as an emergency.
Scotland flag - the saltire Made In Scotland. For Scotland.
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Summary Of The Declaration On The Rights Of Indigenous People
1023 Words5 Pages
In the United States, the indigenous people have been treated unfairly since colonization first began. Indigenous people are treated like they are less than humans. This is not only seen in the United States, but instead is seen all across the country. The unfair treatment and lack of respect for indigenous people led to the need for a document declaring their rights. On September 13th, 2007, the United Nations adopted The Declaration on the Rights of Indigenous Peoples.This document included several themes relating to the rights of indigenous people, including their foundational rights, life and security, language, cultural and spiritual identity, education, employment, self-governance, and several others. As mentioned in lecture, with these themes, the document aimed to encourage nations to work with indigenous people to solve global issues. The Declaration on the Rights of Indigenous Peoples consists of 46 articles. Each of these articles explains a right that the indigenous people have. For example, the first article explains that indigenous people have collective and individual human rights (1). Some of the other rights explained in the first few articles include equality, freedom from discrimination, self-determination, and self-government (1). As explained before, this declaration also covers many other themes than just the foundational rights. For example, there are articles about life and security, identity, social rights, education, employment, among many others
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As part of our Shakespeare repertoire, we have toured Boxed Macbeth for a number of years to schools and theatre venues. Boxed Macbeth last toured in Spring 2014.
This spine-chilling adaptation of Shakespeare’s play uses an imaginative and seamless combination of original text and modern-day speech, with a stunning set that entangles the performers directly in Macbeth’s fatal web of corruption.
Three actors use modern language and physical theatre to chart the devastating effect that one act of evil can have on an honourable and loyal man. Throughout the performance the actors come out of character to engage with the audience to discuss what they are watching and what choices they would make if they were faced with the same circumstances. This interactivity ensures that the students are fully engaged with the production, characters and plot.
Using language that will help them with their GCSE assignments, the students will understand the consequences of the actions of the central characters, be able to discuss the relationships in the play, the changes that happen to the characters and to write about the effects a disturbed character can have on those whom he loves.
See the full photo gallery from this project
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UK due diligence proposals: The people have spoken
13 Oktober 2020
UK due diligence proposals: The people have spoken
On 5 October 2020 the UK government closed its first round of consultation on a proposed law designed to prevent forests and other important natural areas from being illegally converted into agricultural land (FW 258). This proposal would make it illegal for larger businesses to use forest-risk commodities that have not been produced in accordance with relevant local laws in producer countries, and they would need to show that they have taken proportionate action to ensure this is the case. Results from a series of consultations, however, make it clear that people in the UK and partner countries want a more far-reaching law.
NGOs came together to discuss the proposal in a series of webinars and highlighted its major drawbacks. Environmental and human rights groups recommend that a new UK law should go beyond legality and certification; that it should apply to all companies, no matter what size; and that it should include an obligation to carry out due diligence, not only with regard to environmental harm but also human rights.
Groups in heavily forested countries also raised concerns about how European imports impact on natural resources and human rights. In their submission, Brazilian civil society stressed that even though Brazil’s Forest Code already allows for up to 80 per cent devastation within private properties, the government and the agricultural lobby are increasing pressure to permit still more legal deforestation. EcoCare in Ghana pointed out that, although Ghana’s forestry laws prohibit planting cocoa in protected areas, its cocoa laws do not. This conflict in legal interpretation is open to exploitation − which the proposed UK due-diligence regulation does nothing to address. The Cameroonian Forest and Communities Platform highlight that proposed legislation should pay attention to the rights of environmental activists and land tenure rights, as well as the rights of minority social groups (women and Indigenous communities).
More statements are available, and NGOs expect to see these concerns on the scope of proposed legislation reflected in proposals before a further round of consultation on secondary legislation is opened.
Kategorien: News, Forest watch, Sustainable Supply Chains, Certification, Brazil, Ghana
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RT - Journal TY - JOUR A1 - Patel, Dharati A1 - Lahiri, Banibrata A1 - El-Patal, Mohamed A1 - Alazmah, Abdulfatah A1 - Patel, Parth A1 - Abokhlifa, Yousef T1 - To compare and analyze the potency of two topical anesthetic gels in reducing inferior alveolar injection pain in children of 8–12 years: A double-blinded clinical trial YR - 2021/6/1 JF - Journal of Pharmacy And Bioallied Sciences JO - J Pharm Bioall Sci SP - 646 OP - 650 VO - 13 IS - 5 UL - https://www.jpbsonline.org/article.asp?issn=0975-7406;year=2021;volume=13;issue=5;spage=646;epage=650;aulast=Patel;t=5 DO - 10.4103/jpbs.JPBS_772_20 N2 - Aim: To compare and analyze the clinical adequacy of two topical anesthetic gels, Precaine (8% lidocaine + 0.8% dibucaine) and Precaine B (20% benzocaine) in children before intraoral local anesthetic injections. Materials and Methods: This clinical study included thirty children who needed an inferior alveolar nerve block. They were divided into three groups: Group A: Precaine topical gel group, Group B: Precaine B topical gel Group, Group C: no anesthetic topical gel group (control group). These two effective topical gels were applied before giving intraoral local anesthesia, and afterward, the child's pain response was surveyed utilizing the Wong-Baker Faces Pain Rating Scale. The scores obtained were subjected to statistical analysis. Results: Intergroup comparison showed a significant mean difference between the control group and Precaine group (P > 0.05) as well as Precaine B group (P > 0.05). However, there is no significant difference obtained between Group A and Group B (P < 0.05). Conclusion: It is psychologically and clinically beneficial to apply a topical anesthetic agent before injecting any intraoral anesthesia. In this study, both anesthetic gels showed a nonsignificant difference in reducing inferior alveolar injection pain, but Precaine B shows more promising results than Precaine. ER -
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What Does The Sioux Tribe Eat? (Correct answer)
What Does The Sioux Tribe Eat? (Correct answer)
What did the Sioux eat? The Sioux ate buffalo, bear, deer, antelope, turkey and hens. The Sioux shared their food with the whole tribe.
Did the Sioux eat fish?
As vegetables they had potatoes, spinach, and prairie turnip. They also caught fish in nearby streams and rivers. The Sioux rarely went hungry.
Did the Sioux eat horses?
The Sioux only killed as many buffalo as the tribe could use. The women followed the hunters with their pack horses. The men and women would skin the buffalo, cut up the meat, and load it on the horses. Then they all rode back to the camp for fun and feasting.
How did Sioux make their food?
Sioux Indians made their food by roasting it on a spit or broiling it in a skin bag with hot stones.
What is the Sioux tribe known for?
The Sioux tribe were famous for their hunting and warrior culture. Warfare was a central part of the Plains Indian culture which led to inter-tribal conflicts and violent clashes with the white settlers and the US army. Siouan men were noyed for their great courage and physical strength.
Do the Sioux have clans?
Many tribes have sub-tribes, bands, gens, clans and phratry. Often very little information is known or they no longer exist. Anoginajin A band of the Wakpaatonwedan division of the Mdewakanton, named from its chief.
What did the Sioux do for fun?
Many Sioux children like to go hunting and fishing with their fathers. In the past, Indian children had more chores and less time to play, just like early colonists’ children. But they did have dolls and toys to play with, and older boys in some bands liked to play lacrosse.
You might be interested: What Were The Indians Being &Quot;Saved" From What Was The Indian Problem? (Question)
What are some Sioux names?
Common boy names associated with the tribe were; Chatan (Hawk), Chayton (Falcon), Hanska (Tall), Hotah (Strong), Mahkah (Earth), Mato (Bear), Tashunka (Horse), Wambleeska (White eagle), Akecheta (Warrior), Chaska (Eldest son), Makhpia Luta (Red Cloud), Tatanka Ptecila (Little Bull), and Wapasha (Red leaf).
Does the Sioux tribe still exist?
Today, the Great Sioux Nation lives on reservations across almost 3,000 square miles in South Dakota, North Dakota, Montana, Minnesota, and Nebraska. The Pine Ridge Indian Reservation in South Dakota is the second-largest in the United States, with a population of 40,000 members.
What Sioux means?
Background Info: The name “sioux” is short for Nadowessioux, meaning “little snakes”, which was a spiteful nickname given to them by the Ojibwe, their longtime foe. The fur traders abbreviated this name to Sioux and is now commonly used. The Sioux were the dominant tribe in Minnesota in the 17th century.
What meat did the Sioux eat?
Did the Sioux eat berries?
The Sioux were hunters and gatherers. They collected and ate various types of fruit like choke-berries as well as potatoes, nuts, and other fruits. The Sioux also grew corn. They hunted rabbit, buffalo, deer, elk, and birds.
You might be interested: Lenape Indians-How They Lived? (Question)
What did the Ojibwe eat?
Ojibwe people usually did a good job of harvesting the things they needed without using them all. They took only enough fish and other animals— grouse, deer, rabbits, moose, elk, and caribou —to feed their families. Another secret to Ojibwe survival was a strong belief in hard work.
What did the Sioux believe in?
‘Wakan Tanka’ literally means ‘great mystery’. The Sioux tribe believed in spirits which could bring good or evil to their tribe. They feared floods, believing that the waves were evil spirits. Unlike the white settlers, the Sioux only killed animals for food.
What were the Sioux beliefs?
The Sioux were a deeply spiritual people, believing in one all-pervasive god, Wakan Tanka, or the Great Mystery. Religious visions were cultivated and the people communed with the spirit world through music and dance.
What do the Sioux call themselves?
Harold Plumb
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| 0.906173 |
Tellus Group Corporation
Hsinchu, Taiwan
Type: Manufacturing
Small local network in the office. Temporary networks. MDU (Multi Dwelling Unit) networking such as the hotel, dorm, and hospitality, etc. VOIP networking POS networking Surveillance system Existing LAN extension Industrial Ethernet networking such as machine controls, automation network, sensors.
1-4 Layer PCBs $2
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Find the right over-compliance of the verb – There is also a paragraph with some misused verbs in it. A. Itinerary: Choose the appropriate verb from these sentences. We could hardly exist in a world without subjects and verbs that live in harmony. None of our sentences would make sense. But with a solid understanding of the subject-verb agreement, students can write a variety of different types of sentences. Non-conformity of verbs and nouns is a common spelling error. These worksheets prompt students to choose the form of the verb corresponding to the noun. If you are looking for a quiz in the subject-verb agreement, we have two for you. The first set of questions is fundamental and covers simple subjects composed with nouns or singular pronouns and verbs that must correspond depending on whether they are singular or plural.
The second quiz deals with compound topics, complex sentences, and special nouns that adopt singular verbs. Use pronouns and singular/plural verbs – you need to not only choose the right verb, but also label pluralization. Here is the article to end all articles on the asubject-verb agreement: 20 rules of the subject-verb agreement. Students will be able to pass one quiz at a time by learning these rules. Correctly use indeterminate pronouns – you need to mark the indeterminate pronoun in the sentence, and then choose the right verb. Combine the following sentences with an appropriate form of the verb in parentheses. Here you will find all our verb worksheets, from verbs as action words to conjugated verbs, verbs and irregular verbs. Emphasize the accuracy and over-conformity of the verb – Look for the verb and make a change if it doesn`t work for the sentence.
15. Mathematics (is, are) John`s favorite subject, while civics (is, are) Andreas` favorite subject. Complete sentence with the right subject and verb conjunction – Circular the right verb to complete the sentence. Select the correct form of the verb that corresponds to the subject. These subject-verb correspondence exercises with answers cover simple themes as well as compound topics that use „and“ or „or“ to connect individual themes. Once your students have a solid understanding of themes, predicates, and objects, they are well prepared to create masterful complex sentences. This quiz deals with subjects composed with a singular noun and plural vocabulary or pronouns, as well as complex sentences. It`s a fun quiz, as it also covers special names that can be confusing, like collective names and names that end with an „s“ but remain singular.
10. The players, as well as the captain, (want, want) win. 2. Either my mother or my father (is, are) come to meet. 9. The children and their mothers are missing. Find the approval verb and verbs in paragraphs – This sheet basically mixes the capabilities used in the other two worksheets. 21. The members of the commission (guide, guide) are very different in the private sector. 19. There were fifteen candies in that bag. Now there is only one!.
. Find the verb and matching verbs in paragraphs version 2 – More work on the same ability that was identified again. 23. All CDs, even scratched, are in this case. 8. The man with all the birds (live, live) in my street. 4. Either my shoes or your coat (is, are) still on the floor….
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Kos Holidays and Greece Holidays
Kos Sandy beaches, turquoise waters, lush vegetation, ancient and medieval monuments, tree-lined wide roads, large squares, parks, a superb city plan and an extensive bicycle-only routes network are the distinctive characteristics of the third largest island of the Dodecanese, Kos!
The island’s trademark is its medieval castle (Nerantziá Castle) situated at the entrance of the port.Wander along the impressive avenue with the Palm Trees, or stroll around famous squares like Platánou Square and Elefthería Square and admire legendary buildings, remains of the Italian rule.
Interested in history? Pay a visit to the ancient city of Kos and observe important archaeological finds dating back to the 4th century.
Did you actually know that you can sit under the plane tree where Hippocrates himself, the Father of Medicine, used to teach his students and examine his patients? The plane tree must be over 2,500 years old, and it is in fact the oldest in Europe!
4th century Asclipiion, the Antimáhia 15th century castle with its imposing battle tower, as well as one of the most scenic villages of Kos with a distinctive traditional character, Ziá nestled amongst a dense cedar forest.
Book your Kos holidays and Greece holidays with worldwide holidays experts. Adore Holidays offer different Greece holidays and Kos holidays for booking.
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Lesson 2-07 - Principles of Design (redirected from Lesson 2-15 - Principles of Design)
Page history last edited by Luke Shubin 5 years, 11 months ago
The principles of design govern the relationships of the elements used and organize the composition as a whole. Successful design incorporates the use of the principles and elements to serve the designer's purpose and visual goals. There are no rules for their use. The designer's purpose and intent drives the decisions made to achieve harmony between the elements.
After completing this lesson, you will be able to:
Discover the principles of design and find out which are the most important
The principles of design consist of:
Unity refers to a sense that everything in a piece of work belongs there, and makes a whole piece. It is achieved by the use of balance, repetition and/or design harmony.
Harmony is achieved through the sensitive balance of variety and unity. Color harmony may be achieved using complementary or analogous colors. Harmony in design is similarity of components or objects looking like these belong together. Harmony may be visually pleasing and harmony is when some of the objects like drapes and couches share a common trait. A common trait between objects could be: color(s), shape(s), texture, pattern(s), material, theme, style, size, or functionality.
Contrast is the occurrence of differing elements, such as color, value, size, etc. It creates interest and pulls the attention toward the focal point.
Repetition (rhythm, pattern)
The recurrence of elements within a piece: colors, lines, shapes, values, etc. Any element that occurs is generally echoed, often with some variation to maintain interest. Rhythm in interior design also may be used to reduce randomness.
Variety (alternation)
The use of dissimilar elements, which creates interest and uniqueness. Variety like a painting or some reflective wood panels added on a plain wall may be used to reduce monotony. Helps infuse color to a house decor to attempt to increase design beauty.
Emphasis (dominance or focal point)
Emphasis refers to areas of interest that guides the eye into and out of the image through the use of sequence of various levels of focal points, primary focal point, secondary, tertiary, etc. Emphasis hierarchy may give direction and organization to a design, and avoid subconscious confusion to sometimes improve the design's visual appeal and style. Emphasis hierarchy or focus is not giving each object in a project equal dominance within a piece of work. Emphasis or dominance of an object can be increased by making the object larger, more sophisticated, more ornate, by placing it in the foreground, or standout visually more than other objects in a project. The primary focus point or area receives the largest emphasis in a room.
Proportion (scale)
Proportion involves the relationship of size between objects. Proportion is also relative sizes of surface areas of different colors. Proportion also depends on functionality of object. Art painting can be given the correct size in relation to room to make it an effective decorating component or source of color.
A design must have good functionality. Proper functionality is simply the best possible design and best possible location of this design that the occupant(s) requires. Such designs are clean, nearly sterile, tidy, brightly lit, warm, visually appealing, is relatively dry, has relatively clean and healthy breathing air, and exceeds high level health and safety standards. Great functionality and best possible materials for the function usually also increases visual appeal.
Proximity is the placing of similar objects closer together physically, and unlike objects further apart. This aids in creating unity. For example, different furniture styles with different colors compressed in a small bedroom does not look as nice as the same furniture placed further apart in a very large living room.
Color theory
Color theory in interior design includes the color wheel. Color theory involves the idea of how color affects human thoughts and emotions. Color harmony is a pleasing combinations of colors and the amount of these colors in a design like a room decor. Color harmony could also be a visually pleasing color combination that enhances the style and character of a design like a home interior design. Color harmony involves using a limited number of colors in a color palette usually seven or less initially to help preserve design unity. A visually pleasing color combination may be chosen for the color palette of a room for a particular age group and gender.[citation needed]
Decluttering, organization and harmonization of accessories
Neatness or tidyness, clean rooms, construction precision and organization in architecture and home appliances is important. When there is too much storage in rooms, work space must be made by decluttering, organizing and general cleaning. Collected clutter may hide the initial showcase visual appeal of a room. Clutter also makes a room more laborious to clean.
Lighting coloration
Light coloration is important to setting the mood in a photograph or work of visual art. Using various types of lights can denote specific mood changes. For example, a red-light may be used to denote an alert of some sort in the form of a beacon. Differences in lighting can affect the mood as well. Halogen lamps and fluorescents can give a cooler feel to visual design works. These can be replicated through psychological studies.[citation needed] In digital mediums, lighting can be applied through a variety of filters. For example, filtering out noise and changing hues in a subtle manner can give a simple but tolerable logo feel to a red-alert beacon.
Send me an email to [email protected] from your registered gmail account with (Course2_07FirstNameLastName) as the "Subject." In the body of the email, Pick at least 3 principles of design from the lesson and describe why you believe they are the most important. Write a few sentences about each principle. Send me the email. This assignment is worth 20 points.
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How to solve the problem of short-distance cold chain transportation - KingClima
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How to solve the problem of short-distance cold chain transportation?
Aug 27, 2021
As the professional Transport Refrigeration Units manufacturer in China, KingClima not only supply Truck Refrigeration Units, Van Refrigeration, but also Electric Refrigerated Cargo Tricycles.
electric refrigerated cargo tricycles
At present, the cold chain industry is still facing urgent problems, such as the "last mile" of cold chain distribution. Due to the imperfect cold chain system, the phenomenon of "chain broken" and "cold removal" in distribution affects the quality and safety of fresh products.
So How to solve the last mile cold chain transportation problem?
First of all, compared to other logistics areas, the "speed" of fresh food and take-out meals is standard, and the requirements for cold chain distribution timeliness are particularly high. While cold chain express trucks and electric refrigerated trucks improve the delivery timeliness, they also provide strong technical support for the "last mile" cold chain distribution.
Secondly, configure professional cold chain equipment. It is understood that a certain logistics adopts full-process cold chain transportation and professionally customized fresh boxes, which can effectively lock the freshness, while being recyclable and environmentally friendly.
For another example, choose our Electric Refrigerated Cargo Tricycles Solutions. We can provide 1.5*1*1 or 1.8*1.2*1.2 cold chain transport box with the dc powered cooler unit, it have these features:
*DC mobile refrigerators are small in size, easy to move, low in cost, and can be configured with different models of vehicles.
*Electric vehicles and refrigerators are charged separately, and each does not affect each other, and one charge can take 6-8 hours.
*The temperature is refrigerated 2-8 degrees, freezing ≤-18 degrees.
KingClima electric refrigerated tricycle
The vehicle box uses Polyurethane material; inner plate:bottom use stainless steel, others are color plates; foaming thickness:Top 100mm, other 75mm; edging:Aluminum alloy edging; battery:Built-in 45Ah*4, and it can working for 8 hours.
Have questions?
KingThermo sales representatives are available for live chat now
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Financially independent students face challenges while balancing work, school, and money. Currently, there are different scheduling software designs, but most are not tailored towards the specific needs of students. Employers are not aware about class schedules therefore, they cannot effectively take their finances into account. Students may have a number of schedules that is accessed on a different platform which can be cumbersome and leaves room for accidental double-booking. Additionally, when something important comes up and students need to swap or drop shifts, they need to manually check the schedule and contact each employee separately. This is a quite challenging and time-consuming system, that does not help students effectively switch between their schedules.
Our Product
Our product is an employee scheduling website that helps students balance their schedules while tracking their income. Students can access both their personal and academic schedules using one consolidated platform. Our product generates a work schedule for each student that fits best to their prior commitments. This in turn, removes the headache of a poorly made work schedule for both employers and students.
Our research showed that Generation Z doesn't typically budget or track their savings. We added the finances page to help them track their goals and achieve them in a short amount of time. Using this page, they can also access personalized financial tips. For instance, based on one’s school schedule, students will be encouraged to pick up more shifts to not only reach their financial goals but exceed them.
This project highlighted the importance of interpersonal relations, goal setting, communication, motivation, and task delegation within a team.
Carol Yao – Team Lead
Maddy Bosch – Research Lead
Jesse Jakobsh – Research Assistant
Ada Celik – UX/ UI Lead
Francis Boehmer – Graphic Design Lead and UX Assistant
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Mycorrhizal Diversity
Exploring the major changes in soil fungal communities across soil horizons and between adjacent forests dominated by mycorrhizal types
Enhancing our knowledge of the processes that shape ecological community structure, and the consequences for ecosystem function, remains a fundamental goal in community ecology. Microorganisms are a key to understanding these processes and as a result, have become a major focus in plant community and ecosystem ecology. Historically, the impact of microorganisms on plant-soil feedbacks has been largely underestimated in ecology. Among soil microorganisms, fungi are known to strongly affect terrestrial ecosystems. The spatial and temporal variability of fungal communities is central to understand plant diversity and functioning of ecosystems because they directly influence plant nutrition and defense. There is an urgent need to move beyond the soil microbial “black-box” to be able to forecast changes in plant and fungal diversity and their consequences for ecosystem processes.
Maple forest in autumn.
Beautiful podzol with large amount of organic matter.
Collaborators: Etienne Laliberté, Ben Turner, Mélanie Roy and Simon Joly
Mycorrhizas and organic matter decomposition
Is ecosystem carbon storage mediated by mycorrhizas? Experimental approach using co-occurring forests dominated by arbuscular mycorrhizas or ectomycorrhizas
Microorganisms, both above and belowground have a major impact in ecosystem functioning. In particular, an ecosystem function such as carbon cycling is of societal and scientific interest because of its key role in climate change. The aboveground-belowground feedbacks between biotic and abiotic factors control the accumulation and stability of soil carbon. Therefore, understanding the role of soil microorganisms for carbon cycling is fundamental to increase our capacity to predict ecosystem functioning, the future climate of the Earth, and ecosystem response to climate change.
Fungal hyphae colonizing litter in beech forest (Québec, Canada). Collaborator: Etienne Laliberté
Litterbags installed in a Pine plantation (Patagonia Norte, Argentina).
Collaborators: François Teste, Martin Nuñez and Florencia Spalazzi, CONICET.
Physio-chemical and microbial limits of plant range shifts
The temperate forests facing “the boreal wall”: The importance of belowground biotic and abiotic factors on tree establishment
Climate warming has caused many terrestrial organisms to expand their ranges poleward and upward in elevation. If plant distributions were primarily determined by climatic conditions, climate and plant distributions should shift geographically in concert, but many studies show that suitable climatic conditions for a given species shift much faster than species range limits. Although lower success and rate of species range expansion can be due to specific features (e.g., propagule availability), it may also indicate negative impact of non-climatic factors. Further investigation is needed to understand the underlying processes and external drivers of species range limits and potential range shifts.
Mont Mégantic under the cloud, cul-de-sac for the temperate forest?
Collaborators: Mark Vellend and Etienne Laliberté
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Elon Musk's guide to captivate the audience in a virtual event
There are numerous significant obstacles that come in the way of hosting a successful hybrid or virtual event. These vary from ineffective communication to unsatisfactory audience engagement.
If you're like most people and wondering how to prevent these issues in the first place, you've arrived at the right place. In both hybrid and virtual events, you must integrate efficient communication techniques.
Let's discuss the key components that can assist you in incorporating effective communication into your event planning process.
In 2018, Elon Musk sent an email to his staff, where he offered some unique tips for boosting productivity. These four pointers will help you transform your business in the Musk way.
Avoid using complicated idioms or jargon.
"Don't use acronyms or nonsense words for objects, software, or processes. In general, anything that requires an explanation inhibits communication. We don't want people to have to memorize a glossary."
You're wasting your time and your guests' time if you have to explain every industry term. No one ever complains of using a simple glossary, but people will complain about using complicated words.
Choose right speaker(s)
Musk states that a speaker/panelist should leave if they don't add to the event's value. "Walk out of a meeting or drop off a call as soon as it is obvious you aren't adding value. It is not rude to leave; it is rude to make someone stay and waste their time."
A speaker should pay attention to this pointer. If their discussion is not bringing anything to the table, they should consider changing their topic. When you hire speakers with extensive expertise, they are more likely to engage the audience.
Having an engaging speaker also encourages virtual attendees to voice their opinions. As a result, we recommend partnering with successful communicators who are comfortable working with a diverse group and enriching the session for the viewers.
Customize features and build interactivity
Incorporate customized interactive elements to improve audience involvement. How will the virtual guests interact if an organization fails to personalize the event platform appropriately? Virtual guests do not participate when there are no exciting features to engage, share and communicate.
Therefore, it is an organization's responsibility to customize and/or personalize the entire environment and add interactive engagement features. Adding elements like live polls, surveys, one-to-one audio-video calls, games, etc. allow them to share their thoughts.
Almond Virtex is a fully customizable virtual event platform for conferences, exhibitions, launch events, R&R shows, community events, training programs, and other engagement-led initiatives. It's secure, scalable, and extremely easy to use. Leveraging the power of data and analytics, the platform delivers a phenomenal return on experience.
Always have an "Out-of-the-box" idea.
Musk goes on to state that - "In general, always pick common sense as your guide. If following a "company rule" is ridiculous in a particular situation, such that it would make for a great Dilbert cartoon, then the rule should change."
Think out of the box to create an attractive event theme or a group of virtual & content experiences or never-seen-before engagements, which will keep the audience hooked and ensure they remember it fondly days and months later.
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(Article/content is below...)
Rhyme Generator
Words that rhyme with vandagriff
Hm...I can't find anything...
Words that partially rhyme with vandagriff
3 syllable words that partially rhyme with vandagriff
handkerchief iosif vandergriff
2 syllable words that partially rhyme with vandagriff
aliff bailiff bayliff braniff calef calif califf canniff cardiff conniff cosgriff cundiff cunliffe cunniff elliff gatliff heathcliff hinchcliff hinchcliffe hinchliffe hogrefe iliff jolliff jolliffe lahiff massif midkiff nassif northcliff oliff olliff pontiff rackliff rackliffe radcliff radcliffe radliff ratcliff ratcliffe rateliff ratliff ratliffe setliff sheriff sherriff shurtleff shurtliff stancliff sutcliff sutcliffe sutliff tardif tardiff topliff wickliff wickliffe woodliff wycliff yousif zeliff
1 syllable words that partially rhyme with vandagriff
Here are a few rhyme generator examples:
dandelion, floyd, tejas, tangeman, queasiness, ruh, gasping, devine, nine's, pandya, marotto, spyker, chats, mckeone, bureaucracy, mccade, klynveld, blackheath, enright, baylee, dog.
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Server: Channel: #macroquest
In order to connect to the IRC server, you'll need an IRC client. Some IRC clients are:
To join the channel, you first need to register your nickname with the Nickserv bot. You can do this by sending it a message in the following format:
/msg nickserv register<[email protected]>
After registering your nick, on subsequent connections to the server, you'll have to identify yourself before joining the channel.
/msg nickserv identify
After identifying to nickserv, you may join a channel.
/join #macroquest
Some basic IRC commands:
/me- Displays an emote. /nick- Change your display name. /msg- Send a private message to a user. (Alternately, you can use /query in the mIRC client) /part - Leave the current channel. /quit - Self explanitory. /whois- Gain detailed information about a specific user.
It is also wise to not ask overly stupid questions in #macroquest, or you run the risk of being flamed by eqjoe.
Last modified 6mo ago
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Does Haiti and Dominican Republic share the same island?
What separates Haiti from Dominican?
Despite their shared possession of Hispaniola a chasm separates Haiti and the Dominican Republic.
Why is Haiti the poorest country in the world?
The lack of a social infrastructure: inadequate roads, water systems, sewerage, medical services, schools. Unemployment and underemployment. Underdevelopment in an age of international economic competition. Haitian self-image.
Why is Haiti so poor and Dominican Republic not?
Haiti is the poorest country in the Western Hemisphere. The population is predominantly French Creole-speaking descendants of African slaves brought here during the slavery time. If you’re born on this side of the border you are ten times poorer than if you are born in the Dominican Republic.
What are the similarities between Haiti and Dominican Republic?
The Dominican Republic and Haiti share the same island of Hispaniola. They also share common historical experiences, including colonial origin, American occupation, and former autocratic regimes that have recently transitioned to young democracies.
What is the relationship between Dominican Republic and Haiti?
Relations have long been complex due to the substantial ethnic and cultural differences between the two nations and their sharing of the island of Hispaniola, part of the Greater Antilles archipelago in the Caribbean region. Living standards in the Dominican Republic are considerably higher than those in Haiti.
IT IS INTERESTING: Can you share Apple music without family sharing?
Why did Haiti fail?
Once the wealthiest colony in the Americas, Haiti is now the Western Hemisphere’s poorest country, with more than half of its population living below the World Bank’s poverty line. Foreign intervention and debt, political instability, and natural disasters have stymied the Caribbean country’s development.
Is Dominican Republic a third world country?
“Third World” lost its political root and came to refer to economically poor and non-industrialized countries, as well as newly industrialized countries.
Third World Countries 2021.
Country Human Development Index 2021 Population
Dominican Republic 0.736 10,953,703
Fiji 0.741 902,906
Mongolia 0.741 3,329,289
Saint Lucia 0.747 184,400
What is the name of the people who inhabited the Dominican Republic before Columbus arrival?
At the time of Columbus’s exploration, the Taíno were the most numerous indigenous people of the Caribbean and inhabited what are now Cuba, Jamaica, Haiti, the Dominican Republic, Puerto Rico, and the Virgin Islands.
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Date of Award
Document Type
Degree Name
Doctor of Education (EdD)
School of Teaching and Learning
First Advisor
Elizabeth A. Skinner
Success in school is something that every student tries and accomplishes in different ways, but this is not a simple matter of just demonstrating academic success. Students may have the best grades, but if they do not master the “college student” (Collier, Morgan, 2004) role, many students may not succeed. When students master this role, it will help them understand the different expectations professors may have and then will be able to apply their academic skills effectively and help them meet these expectations. This is something that many students know and understand, and this information is not passed on to them from their high school teachers or counselors but from their parents, or relatives that have 1st hand knowledge of the college student. When the student does not possess this information the chances of continuing on past high school decrease. This information I believe, can make the difference and can increase the success of Latino students no matter what school they attend. This study is significant because it aims to identify what successful practices were implemented by Latin@s within a large school district. Their personal accounts provide an understanding of what helped this small group of individuals achieved personal success and now have an opportunity to continue their education. The significance does not just have a simple effect on the district but requires a change to happen if the district is going to meet the needs of its growing Latin@ student body.
Imported from ProQuest Rodriguez_ilstu_0092E_11589.pdf
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Included in
Education Commons
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Best answer: When did America occupy the Philippines?
United States/Philippines (1898-1946) Crisis Phase (December 10, 1898-October 31, 1899): The U.S. government formally acquired the Philippines from Spain with the signing of the Treaty of Paris on December 10, 1898. The U.S. government declared military rule in the Philippines on December 21, 1898.
When was the Philippines colonized by America?
Spain established its first permanent settlement in the Philippines in 1565. Spanish colonial control of the Philippines continued until 1898, when the United States took possession of the islands as a territory after winning the Spanish-American War.
Why did the US invade the Philippines?
The conflict arose when the First Philippine Republic objected to the terms of the Treaty of Paris under which the United States took possession of the Philippines from Spain, ending the Spanish–American War. … On June 2, 1899, the First Philippine Republic officially declared war against the United States.
How did America rule the Philippines?
The period of American colonialization of the Philippines lasted 48 years, from cession of the Philippines to the U.S. by Spain in 1898 to U.S. recognition of Philippine independence in 1946. … America then held the Philippines until granting full independence on July 4, 1946.
Did Spain sold the Philippines to the US government?
Apart from guaranteeing the independence of Cuba, the treaty also forced Spain to cede Guam and Puerto Rico to the United States. Spain also agreed to sell the Philippines to the United States for the sum of $20 million. The U.S. Senate ratified the treaty on February 6, 1899, by a margin of only one vote.
FASCINATINGLY: When did the US buy the Philippines?
Was Japan colonized or a colonizer?
Japan was not formally colonized by Western powers, but was a colonizer itself. It has, however, experienced formal semicolonial situations, and modern Japan was profoundly influenced by Western colonialism in wide-ranging ways.
Keep Calm and Travel
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Liv-gen 15mL
Product Code: 883196116614
Availability:Out of stock
BRAND Genestra Brands
CATEGORY Phyto-gens
KEY INGREDIENTS Black Currant Bud Extract, English Walnut Bud Extract, Juniper Young Shoot Extract
SIZE 0.5 fl oz
Recommended Dose:
Adults and Children (over 12 years): Take 10 drops once daily, or as recommended by your healthcare practitioner. Invert bottle to 45° and shake lightly allowing drops to fall directly into mouth or in 1/4 oz. of water.
Risk Information:
If you are pregnant or if you have a kidney disorder, do not use. If you are breastfeeding, do not use, unless directed by your healthcare practitioner. If symptoms persist or worsen, consult your healthcare practitioner.Guaranteed to contain no added starch, yeast, gluten, corn, soy, sodium, sugar, artificial coloring or flavoring, antimicrobial preservatives, dairy or animal products. Ideal for vegans.
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Home Real Estate Making an offer on a property
Making an offer on a property
by AEA Staff
A home is the ultimate symbol of one’s financial success, a point of fulfilling the American dream. For many, buying a home is the ultimate goal of a fulfilling life. To cross the finish line, you must first begin a journey of negotiation with the seller. The prospect of offer acceptance among buyers is determined by the amount of money off the list price.
There are many factors to take into consideration when deciding a winning offer, including your gender. The more you are willing to pay above the listing price, the more likely the seller is to accept your offer. Furthermore, your credit score can have a significant impact on the amount of money the seller is willing to accept. A house can increase in worth about 8% annually, but amortization decreases 5% annually. Therefore, a buyer should buy a house at the right price with their yearly income in mind if they want to avoid financial troubles
1. Appraise the property
2. Make an offer foundation
3. Realtor expert’s input
4. Closing: paperwork
5. Finances
6. Inspecting property
7. Making an offer
8. Acceptance
9. Final payments
In detail
1. Agencies typically starts by appraising the property of its worthiness. What kind of property is this, and how much do you plan to pay?
2. Make an offer and document it to be certain that there’s a paper trail if the offer is declined or later amended.
3. Real estate experts are trained on understanding the scenarios that may happen and provide feedback.
4. The offer and acceptance today we within the digital world, meaning that it may just be a letter, an email, a call, or even a text.
5. This could involve carrying out a series of titles, acquisition costs, and the mortgage budget to ensure you could be authorized for a loan and should be able to realistically construct mortgage payments.
6. Inspecting property involves touring the buildings, and noticing anything that is broken and needs repaired.
7. Making an offer may be contingent upon various aspects, like the mortgage.
8. Once the offer is accepted, it gets better to work on a contract and agreement about the terms of the buy.
9. The final payment is the cost of ownership, which includes property taxes, association dues, insurance premiums, and interest on your home loan.
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The Pale Prince
This includes The Pale Prince miniatures. It sits on a (50.8mm) base. It comes in 5 poses. It also includes a spiritual weapon and a bust.
You can find my latest releases over on my Patreon!
The Pale Prince
One of the youngest members of the Fey Winter Court, The Pale Prince is a powerful Archfey that was once a member of The Summer Court.
The brooding Prince of Winter used to be bright, flamboyant and radiant centuries ago. Until he fell deeply in love with a mortal from the material plane. He was warned of such things to be frivolous and will only lead to heartache. These words fell on deaf ears as passions ran high.
Eventually, he brought his love to his home in the fey wilds. A beautiful palace of wonder, filled with flowers and the joys of spring and summer. A delight at first and eventually the grandeur became common. She loved The Prince, but her heart longed for her home outside the fey wilds. She tried to explain how she felt, but he could not comprehend the idea of going back to a world full hardship. He would not truly listen, but always tried to comfort her afterwards.
After years, she grew distant and cold. Eventually, all that was left for The Prince was a note on his pillow. She had left for her home, she wanted to see the passing of days and the life she once had. A life of excitement or even peril and to venture into the unknown. She wanted to return to a life of not knowing what could come next, a life of adventure. She would cherish their time together, but this was not the life for her.
Pain. That is all he felt as he read the words. The palace grew dark as his emotions infected his surroundings. The plants withered and cried, the animals all around hid from him and even the palace appeared as if it were closing in around him.
In his rage, he went to search for her. Years had passed between their realms of existence. Eventually, he found her camping with a group of companions. He watched from the shadows before he would make his appearance. Minutes felt like hours as he realized she looked happy without him as she held the hand of another by the fire.
The warmth of summer left him in that moment as he drew his blade and made himself known. She knew this day was coming and she had prepared. Her face looked in horror as The Prince stared at the companion she sat beside. The Prince dashed with tears streaming from his eyes, his blade pointed to the one beside his love. She cast a spell to shift them to a new plane of existence.
Blood trickled from the tip of the blade. He was alone beside the campfire as it grew dim and cold. For years he searched and could not find them. The feelings of betrayal and heartbreak festered. When he returned he found his palace as a desolate ruin. It no longer was his home, it was a dungeon of heartache and misery.
His siblings found him as he mourned the times before heartache. They told him that his love had help from a god or goddess to avoid him. However, which one they did not know or would not tell him. These words only brought more pain and he was done with their games. He left the lands of Summer and Day. He ventured to the home of Night and Winter, a place where he felt truly at home.
The Lands of Neverending Night were cruel and unforgiving. The lands were a reflection of him and the terrible creatures of the cold dark that began to serve him. Slowly the frost encrusted his armour as wandered. Then he made himself a new home, a palace of frost - a frozen throne.
His last moments as The Summer Prince were painful as he could no longer bear his emotions. He tore out his heart and placed it deep within the throne of ice. All that was left in him was sorrow and his heart would be hidden from all. He grew numb to pain, but he still could not give up searching for his love. Soon he would wage a war against those that hid her from him.
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The emergence of the polyrhythmic sounds of what today is known as Afrobeat has been on a steady incline since the late 2000s. As the king of Afrobeat, Nigerian-born Fela Anikulapo Kuti first established this style of music by incorporating sounds of jazz, funk, soul and African juju. But to listeners, Afrobeat music was more than just its distinct African sound; it was a political movement that bolstered black empowerment. Fela was known as a strong social, cultural, economic and political commentator about not just the Nigerian government, but narratives on ‘Blackism’ – nationalist ideologies surrounding the 1960’s black power movement in the United States (Botchway, 2014; Collins, 2004; Olanlyan, 2004). Fela’s music was used as a weapon to protect against Nigeria’s federalist regime and postcolonialism (Sithole, 2012); the lyrical power that emerged from Afrobeat highlights the genre’s inherently political and anti-establishment messages (Gendreau, 2009; Sithole, 2012). Today, fans of Afrobeat look to Fela’s music in bridging the gap between black tradition in Africa to the spread of African nationalism across the globe, particularly in the United States and the United Kingdom.
This convergence between native African sounds and Western music, however, came with a cost. African beats were borrowed, commoditized and sold by U.S. producers to Western listeners who consumed the genre as a generic, digestible and monolithic style of Afrocentrism (Akinsete, 2019). Hip hop and rhythm and blues (R&B), for example, thus became avenues to express collective oppression, black aspirations and cultural consideration in the U.S. (Henderson, 1996). With Afrobeat, Fela ‘purists’ are fighting to filter Western and Euro-centric pop culture pressures from soiling the genre by labelling it ‘Afropop’ or ‘Afrofusion,’ instead of more appropriately calling it Ghanaian or Nigerian pop music (Akinsete, 2019). Maintaining a piece of African heritage, as it is expressed through music, remains a relentless effort in preserving black culture from white popularization. Thus, the drive to reinstate cultural art and narratives as symbolism of black power became a force that emerged to avoid the “constant burden of performance under a Western gaze” (Akinsete, 2019, Okay Africa).
But the portrayal of black representation in the U.S. diverges from what was happening in the U.K.; representations of black British culture fell in the shadows of black empowerment in America at the height of the Civil Rights movement. Moreover, Britain’s school curriculum held little to no information about cultural black history (The Guardian, 2013). Differences in how British black identity and power is represented through music, and specifically Afrobeat, is thus an interesting comparison. More specifically, this qualitative research seeks to answer the following question: how do British individuals within the African diaspora understand representations of black identity in Afrobeat?
The global theme that emerged surrounding Afrobeat was a negotiation of narratives over representations of African identity. Afrobeat, or simply African music, has transcended historical themes from post-colonialism to the celebration of black identity. However, participants expressed how Western influence on Afrobeat attempts to dictate their assumptions of what “Africanness” is, suggesting a continued struggle of assertion over representations of one’s black identity.
Theme 1: Power over and protection of representations of African identity in Afrobeat
One key finding that emerged was the dominating Western narratives of what “Africanness” is supposed to be. In reference to the Grammy awards, one participant notes: <quotes from participants were removed to ensure anonymity>. This in turn led to the commoditization and accessorizing of black identity being catered to white consumers, which led to feelings of disempowerment: <quotes from participants were removed to ensure anonymity>. However, with the popularization of black music, another participant observes that “it’s cool to be African” again. But this comes at the expense of white acceptance and a disregard for perpetual underlying racial issues: <quotes from participants were removed to ensure anonymity>. Amidst this cultural appropriation, the maintenance of cultural authenticity to protect black identity was a recurrent theme: <quotes from participants were removed to ensure anonymity>
Theme 2: Dichotomous experiences between native Africans and African Americans
A divide between narratives emerged between native Africans and the global African diaspora during Ghana’s Year of Return in 2019 to commemorate the beginning of slavery. Interestingly, one of the participants used the term “us”, even though British, in referencing a separate experience in the U.S.: <quotes from participants were removed to ensure anonymity> Beyond this dichotomous experience, another discrepancy exists between the narratives that Afrobeat historically represented to what lyrics are representing today: <quotes from participants were removed to ensure anonymity>. Not only are there different experiences occurring simultaneously between native Africans and the African diaspora, but the historical context of Afrobeat is also removed from modern day Western consumption. Despite this change in narrative, Afrobeat today represents celebration of black identity: <quotes from participants were removed to ensure anonymity>.
Theme 3: Connecting through cultural transcendence and shared identity
Despite Western monolithic perspectives of black identity, it enhances connection and a sense of community between native Africans and the African diaspora across the globe: <quotes from participants were removed to ensure anonymity>. Afrobeat also provides an avenue that connects historical narratives of Afrobeat to contemporary Western listeners: <quotes from participants were removed to ensure anonymity>.
The underlying narratives surrounding Afrobeat were multi-voiced. Firstly, Afrobeat was deemed as simply African music; the name Afrobeat was observed to be more of a term created as a digestible concept for Western ears. Additionally, original narratives of political, social commentary during Fela’s time are no longer present in modern Afrobeat. Instead, it is about celebrating black identity, without lyrical hints of post-colonialism and anti-establishment. This narrative seeks to separate black identity from an incessant struggle not only from the perceptions of white individuals, but individuals also within the African diaspora. Moreover, the participants identified with the U.S. experience of being black, despite different historical contexts within black empowerment. Despite this dichotomy, the message is about celebrating black identity for what it is, not for what it represents.
However, an interesting juxtaposition arises; while participants note the importance of separating narratives of black identity from the Western gaze, there continues to be a struggle to assert power and representations of black cultural authenticity. Since its global ascendance, a negotiation arose to maintain native African heritage while transcending representational boundaries of black communities (i.e. native Africans and the global African diaspora). This supports the existing research and commentary about African music being a commodity to Western listeners as a generic style of Afrocentrism (Akinsete, 2019). This study reifies the continual attempt for black communities to escape socially constructed discourse from non-African individuals and reinstate their identity and culture through avenues, such as music, that symbolize power.
Social representations of identity are closely linked to insights found in this research. Social representations are meaning-making infrastructures that allow individuals to classify others (Moscovici, 1973) through legitimizing myths (Sidanius et al, 2017). As abstract thoughts of what Africanness means become inseparable from the reality of the Western gaze, black individuals become categorized into cultural stereotypes and cemented in historical contexts (Moscovici, 1961). A discrepancy of what it means to be native African and a part of the African diaspora outside Africa is highlighted in both White and African-American contexts. Despite these diverging narratives, contemporary Afrobeat continues to bridge the gap between black tradition in Africa to the spread of African nationalism.
While it is difficult for minorities to escape such myths based on Western perspectives, individuals can shift their identity and re-categorize to satisfy various needs and cultural practices (Brewer, M.B. et al., 1996; Brewer et al., 1991). Future considerations for research should explore African myths of black identity, and how these are reinforced or dispelled in Afrobeat. Understanding and deciphering cultural representations may help to dispel myths and ways of deconstructing social representations through culturally symbolic art forms. It may also help to address the problematic monolithic representations of black individuals. Research should also consider examining social representations in traditional African music, as opposed to limiting the genre to Afrobeat to examine any similarities or differences.
This current study hopes to offer insight into how British Africans who listen to Afrobeat understand representations of black identity amidst the gaze of Western listeners. It further highlights the importance of empowering black individuals through music and other avenues of artistic expression to maintain a sense of power over their narratives, as well as de-construct and obliterate monolithic generalizations of Afrocentrism.
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Main Content
The Kelly Clarkson Show
Kelly Reads Santa’s Letters Back To Kids!
Also available on the nbc app
Lifestyle expert Danielle Kartes shows Kelly how she and her young boys use incredible, ERASABLE FriXion pens and markers to write truly magical letters to Santa, and then ‘zaps’ them to the North Pole using a simple kitchen appliance. Then, Kelly pulls the boys’ letters from the freezer, and uses magic (or science!) to surprise them with a response from Santa!
Appearing:Kelly Clarkson
Tags: Kelly Clarkson, entertainment, music, daytime, santa, letters, kids, reads
S2 E05 minTV-PGHighlightTalk and InterviewDaytime
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General Chemistry I at Stan State
Current COVID-19 statistics
General Chemistry I at Stan State
Dr. Stone, ude.natsusc|enotsk#ude.natsusc|enotsk, Zoom office hours by Zoom, appointment needed.
Supplemental Instructor: Sara Buenrostros
Dates and times for SI: W 1-2:30, F 8:30-10
Tutoring Center
Spring 2021 syllabus
There will be a quiz every day except June 14, July 5 (holiday) and July 23(cumulative final). Quizzes will be on Canvas, 50 min, they open at 5pm and close at noon the next day.
Classes will be synchronous Zoom meetings.
Assignments are not accepted after the due date. In class assignments are due at midnight every day. If you miss a deadline, you forfeit the points and that will decrease your overall percentage.
Working with Excel
All scores will be posted on Canvas
Materials for Quiz 1, 2, and 3:
1. Read Chapters 1 and 2
Quiz 1
2. Metric Madness and here is the worksheet
4. Names and numbers: Quiz yourself!
5. Power point slides for Significant Figures and Practice problems
6. Density slides
8. Whiteboard lesson: Density
Quiz 2
3. Atoms, Isotopes and Ions powerpoint.
Quiz 3
2. worksheet for Monday Feb 15
3. Names and %Abundance and here is the worksheet
4. Ions and nuclear chemistry and here is the worksheet
6. How to Calculate Percent Abundance,
Materials for Quizzes 4, 5 and 6
• End of chapter 3 problems: 1,2,3,4,5,6,7,8,16,17,20,25,29,31,33,37,49,51,53,55,61,62,63,65,75,76,77,79,81,83,85,87,91,93,97,99,101,105,107,109,111,113
Quiz 4
Quiz 5
Materials for Quizes 6,7 and 8
1. Watch the videos on the site for the book.
Quiz 6
2. Solubility Rules, quizlet I
3. Practice using the solubility rules, quizlet II
4. Solubility rules Lecture slides and clicker questions
5. Practice for Summer 2016 quiz and here are the answers
6. practice for net ionic equations and solubility rules answers
7. Precipitation reactions Lecture slides and clicker questions
8. Table of ions that may or may not precipitate
9. Here is some help for Smartwork problems.
Quiz 7 March 19
1. Redox reactions Lecture slides and clicker questions, assign oxidation numbers, know what is reduced and what is oxidized. Also, there is titration and precipitation problems on this quiz. Watch the zoom from Monday.
Quiz 8
1. More Redox Lecture slides and clicker questions, breathalyzer reaction.
2. Redox, Electrolytes, Acids and Bases Lecture slides and clicker questions.
3. Balance Redox Equations
4. Practice for Redox and answers
5. Notes for Balancing Redox reactions.
6. A white board Redox Lesson
Materials for quizzes 9,10,11
1. End of Chapter 5 problems: 2,3,4,5,13,15,16,17,18,31,43,47,57,67,73,77,78,99,100,103,105,115,121,131
1. End of Chapter 6 problems: 2,7,10,18,19,20,27,33,37,39,43,47,49,51,53,55,57,61,65,67,69,71,73,75,77,78,81,83,85,87,89,92,93,94,
1. Practice Exam Note: the answer to #20 is wrong.
Quiz 9
1. Gases, Part I Lecture notes and clicker questions
2. Gases, Part II Lecture notes and clicker questions
3. Gases, Part III Lecture notes and clicker questions
4. Gases, Part IV Lecture notes and clicker questions
Quiz 10
4. Enthalpy, Entropy, 1st and 2nd Law Lecture notes and clicker questions
Quiz 11
Materials for quizzes 12, 13, 14
1. End of Chapter 7 problems:11,15,16,17,18,31,41,45,103,105
Quiz 12
Quiz 13
Quiz 14:
2. # End of Chapter 8 problems:9,12,13,109,127,129,131,133, 140,141
Quiz 15:
2. Old quiz from Practice for Quiz10,Summer 2015 answers
2. End of Chapter 9 problems:49,50
1. # Great site for VSEPR!
Page updated by Dr. Stone on July 11, 2021
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Develop a work-family program
A recent employee satisfaction at the Mid-American Widgets Corporation revealed that employees are struggling to manage their work and family commitments, reducing employee satisfaction and company morale. You are hired to develop a work-family program that helps employees balance work and family while also improving company productivity, customer service, and ultimately the bottom line.
In a 2-3 page paper, present the work-family program you would implement. Include details, explaining the specific policies your program would include and how these would impact both employees and employer, using information from the course reading to support your points.
Use Discount Code "Newclient" for a 15% Discount!
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The steric number is equal to the number of $\sigma$-bonds + the number of lone pairs of electrons on the central atom. It gives us the number of hybridised orbitals.
It is pretty straight-forward to calculate it, but the problem here is that one must always draw the Lewis Structure before one can actually get to calculating the steric number, and then the number and types of hybrid orbitals. Even that is quite simple for a smaller compound, even like XeF$_6$, but when it comes to complex hydrocarbons, it's a little difficult.
My question is that is there any well-known (or not so well-known, but working) shortcut to doing this, so as to save time? It would be great if anyone could share their ideas and help me out.
Thanks in advance.
• 1
$\begingroup$ I’ld like to point out that your first and second sentences contradict themselves. Take for example $\ce{SF4}$. We have two 2-electron-2-centre (2e2c) $\ce{S-F}$ $\sigma$ bonds and one (also 4e3c $\ce{F\bond{...}S\bond{...}F}$ bond. We also have one additional lone pair. The 4e3c bond is also $\sigma$-symmetric. Therefore, we have three or four $\sigma$ bonds — depending on how you count — and thus a steric number of four or five. However, sulphur is $\mathrm{sp^2}$ hybridised, i.e. only three orbitals take part in hybridisation. $\endgroup$
– Jan
Jun 18 '17 at 17:04
• $\begingroup$ This question was posted before I had learned about the concept of banana bonds, and other special bonds, in which multiple centres are present (such as 4e3c, and 2e3c). Hence, I assumed that in all compounds, steric number equals the number of hybridised orbitals. $\endgroup$
– Abhigyan
Jun 19 '17 at 11:54
Short answer: no.
The steric number is a property of an atom, not a compound. You need to know what an atom connected to a given atom to know its steric number. For simple compounds, you can usually determine these connections because the formula suggests a central atom and surrounding groups. For hydrocarbons and other organic compounds, you need to consider isomerism. Given the capability of carbon to form complicated bonding patterns, even simple formulas can produce a fair number of isomers with different bonding patterns and steric numbers.
Let's look at some examples.
This formula corresponds to two compounds with the structures shown:
enter image description here
In this case, both compounds have all four carbon atoms with steric number of 4.
it is not always true that a set of hydrocarbon isomers will always have the same steric number for all carbon atoms or even the same set of steric numbers.
This formula corresponds to six isomers:
enter image description here
Note that four of these structures have two carbon atoms with steric number 4 and two carbon atoms with steric number 3. The other two have all four carbon atoms with steric number 4.
Any method to calculate steric number for carbon atoms in an organic compound using just the formula will fail. You must examine the structure.
All right … I found myself a shortcut, and would like to share this in case it is useful for others. However, this formula is applicable to molecules with only one central atom.
Here is how it goes:
1. Find $N=\frac{V+M \pm I}{2}$, where $V = n(\ce{e-})$, the number of valence electrons of central atom, which is equal to the group number according to the old IUPAC system, $M = n(\text{atom})$, the number of monovalent atoms directly bonded to it, and $I$ is the number of positive or negative charges present (subtract it if the charge is positive, and add it if the charge is negative). This $N$ is the Steric Number.
2. Now, find the number of Bond Pairs ($BP$) of electrons, which is equal to the number of atoms surrounding the central atom. However, this is a little difficult for a species like $\ce{H3BO3}$, which is actually $\ce{B(OH)3}$, when written according the IUPAC method of writing the less electronegative atoms first.
3. Next, find the number of Lone Pairs ($LP$) of electrons, which is equal to $N-BP$.
4. Now, draw the structure of the atom, using the central atom, drawing the skeleton of the atom using the steric number, and then assigning the Bond Pairs and Lone pairs to the respective bonds/atoms.
That's for an atom with a single central atom.
Now, for a Hydrocarbon, albeit it is not possible to get the shape directly from the molecular formula, it is possible to find its structure and hybridisation if and only if the basic structure of the atom is provided.
1. For a compound with a single $\sigma$ bond between Carbon atoms, the hybridisation is $sp^3$
2. For one $\sigma$ and one $\pi$ bond, it is $sp^2$ hybridised, and
3. For one $\sigma$ and two $\pi$ bonds, it is $sp$ hybridised.
So, essentially, there is no formula for hydrocarbons, but there is a formula for smaller compounds, with a single central atom only.
Here is an alternate method for one central atom molecules which I found in JD LEE adapted by Sudarshan Guha ed 2021.
Motivation: This method assumes that all the corner atoms have complete octet. Number of $\sigma$ bonds $=$ Number of corner atoms.
1. Define $n$ to be: total valence shell electrons of all atoms + number of negative charge(if any)- number of positive charge (if any).
2. Write $n$ in the following form: $n = 8j+k $ with $k<8$ and $j>0$
It is now useful to define $Q= 8j$ and $R= k$, it turns out that $Q$ is number of $\sigma$ bond pairs and $R$ is number of non bonding electrons on central atom.
Important point: To make this method work, we have to consider the valence electron of hydrogen as $7$ (because this method assumes that all the corner atoms have complete octet). Otherwise your calculations will go wrong.
1. The steric number number is given as: $S = Q + \frac{R}{2}$
Hence, from $n$ , we find the non bonding pairs, bond pairs and finally the steric number.
Example calculation:
Consider methane $\ce{CH4}$, due to absence of charges, $n$ is given as the total valence electrons i.e: $4+ 4 \cdot 7=36= 8 \cdot 4$. We see that $Q=4$ , $R=0$ and $S=4$ hence four bond pairs, no lone pairs and tetrahedral geometry.
Show, using the above method, that the steric number of $XeF_5^+$ is $6$
Figure out how to extend this method to the molecule $\ce{HNO3}$
I have been teaching my students the same shortcut by AbhigyanC, but expressed a bit differently. Using the same symbols:
LP = (V-M-I)/2
LP = No. of lone pairs on central atom
V = No. valence electrons brought by central atom
M = No. of hydrogens or halogens bonded to the central atom
I = Charge of the species
It is a rearrangement of the formal charge formula, and uses the following additional observations:
• Hydrogen always makes single bonds
• Halogens make single bonds when they are peripheral (at least good enough for General Chemistry)
• The net charge can be assigned to the central atom because the allowed peripheral atoms do not take on nonzero formal charges
Of course the steric number is: N = M + LP
This shortcut allows me (and any student who adopts it) to simply look at a formula and come up with the VSEPR prediction with a simple mental calculation!
Your Answer
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7.5 Reassessments under the Repealed Acts | Military Compensation SRCA Manuals and Resources Library, Permanent Impairment Handbook, Ch 7 Assessments under the 1971 and 1930 Acts
You are here
7.5 Reassessments under the Repealed Acts
Last amended
26 July 2021
A reassessment occurs when a client who has received compensation under both the Compensation (Commonwealth Employees) Act 1971 or the Commonwealth Employees' Compensation Act 1930 seeks additional compensation where their overall degree impairment has increased.
Unlike reassessments under the Safety, Rehabilitation and Compensation (Defence-related Claims) Act 1988 (DRCA) where additional compensation is only payable for an increase in impairment if it meets the prescribed threshold, additional amounts of compensation can be paid for any percentage increase in loss of efficient use under the 1971 Act and 1930 Act.
Therefore, a person can make a request for reassessment under the 1971 Act and 1930 Act where they believe their condition has worsened, and as a result their degree of impairment would have increased. Medical evidence will need to be obtained to support the claim. Where the medical evidence supports the person’s impairment has increased (regardless of the degree the impairment has increased by) since the previous assessment and determination, a delegate is able to make an assessment under the Table of Losses and determine an additional amount of compensation is payable.
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REACHing Peers
Reaching Peers LogoResources in Education and Advocacy for Current Huskies, or REACHing Peers is a three-fold peer mentoring program that consists of:
3. Linking current UConn students with a network of CSD alumni for career and post-graduate preparation.
The goals of REACHing Peers are to:
• Create a network of peers to support incoming students in their transitions to UConn.
• Provide students with a sense of belonging and connectedness at UConn.
• Provide opportunities for experienced students registered with the CSD to assist incoming students through similar experiences, such as learning CSD procedures (e.g., requesting accommodation letters, coordinating accommodations), adjusting to life in the residence halls, and communicating with faculty.
For more information about the REACHing Peers program, please email Allison Knight, Disability Service Professional, at
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Throughout history, people have always claimed pieces of territory as their own. They called their place a nation.
Now's your chance to claim a piece of land on earth and either rule or be ruled. You can lead your nation through a golden era, or see it collapse into a new dark age. Have your nation assert global and economic hegemony, or have it be partitioned and forced to obey the diktats of powerful neighbours. The choice is yours.
You may think that it's not as interesting as many other RP's and that it's the same old roleplay. But what if we told you that it's not a roleplay? What if we told you that it's a grand strategy game? And what if combat, diplomacy, economics, politics, technology, and the simulated fate of entire nations were decided by one of the most complex bots on Discord?
Forty thousand lines of code. We're a server dedicated to consistently pushing the boundaries of what we can achieve on Discord through innovative new ideas and tireless bot development. With plans set in motion for new technical and engineering marvels, and with our coding abilities, we shall push the future of Discord bots, together.
Innovate. Lead. Join us.
Similar servers you might like:
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Preparing For School Over Summer Break
Just because it’s summer break doesn’t mean progress can’t be gained. Use this summer to prepare for the success of next school year by following these tips:
1. Maintain a consistent schedule as much as possible. This helps the entire family, too. Even if you have other children without Autism, create a schedule for them too.
2. Include 10 minutes a day working on turn-taking and sharing with siblings. If you have an ABA program, ask your BCBA for advice on how to teach turn-taking and sharing skills.
3. Refer to the schedule throughout the day to prepare your child with Autism and let him or her know what to expect.
4. Include novel activities at least twice a week. For example, leave a space in the schedule that says, “Fun!” so your child can also be flexible and understand that not every second needs to be scheduled. Some fun ideas include sidewalk paint, gross motor obstacle outside, sand or water table (Tip: use an empty plastic storage container on two chairs).
Last but not least, don’t forget the sunscreen!
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Product Idea |
Sailing Yacht
A classic model of a classic sailing yacht. Perfect for desktop or shelf-top display, or... just a blast to remove from its stand and play with! The design includes 3 tall masts, plus the jib, a flowing keel, and includes a small dingy on the stern. The ship features some unique building techniques, leading to its smooth, model-like appearance.
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Question: How do I know if my postpartum stitches are infected?
How do you know if your stitches are infected after birth?
If your stitches have become infected, you may notice the following symptoms:
1. redness or swelling around the stitches.
2. fever.
3. an increase in pain or tenderness at the wound.
4. warmth at or around the site.
5. blood or pus leaking from the stitches, which may have a foul odor.
6. swollen lymph nodes.
When should I be worried about postpartum stitches?
Call your healthcare provider if you have:
• Heavy or gushing bleeding from the vagina.
• Discharge that has a bad odor.
• If your episiotomy or tear opens.
• Fever or chills.
What do infected vaginal stitches feel like?
IT IS INTERESTING: Your question: Can you line a knitted cardigan?
How long does it take for vaginal stitches to heal?
How do you tell if stitches are healing properly?
What does infected stitches look like?
redness or red streaks around the area. tender and swollen lymph nodes closest to the location of the stitches. pain when they touch the stitches or move the injured area. swelling, a feeling of warmth, or pain on or around the stitches.
How do you clean postpartum stitches?
Keep clean
1. Gently wipe from front to back after you urinate or have a bowel movement.
2. After wiping, spray warm water on the stitches. Pat dry. …
3. Don’t use soap or any solution except water unless instructed by your healthcare provider.
4. Change sanitary pads at least every 2 to 4 hours.
What happens if my perineal stitches open?
IT IS INTERESTING: Question: What is edge to edge sewing?
What helps stitches heal faster after birth?
How to soothe stitches after birth
1. Keep the area clean. …
2. Use soothing products. …
3. Change sanitary pads regularly. …
5. Keep an eye out for abnormalities. …
6. Wash your hands. …
7. Take regular pain relief. …
8. Eat healthily and drink water.
Can cervix tear during delivery?
Clinically significant lesions of the cervix occur in 0.2–1.7% of vaginal deliveries 1. Cervical tears have been frequently reported with instrumental delivery, particularly when forceps was engaged. However, large tears that mimic a full dilatation and lead to fetus delivery are ultimate rarity.
When can I start doing household work after delivery?
How do I know if my episiotomy stitches are infected?
1. red, swollen skin.
2. discharge of pus or liquid from the cut.
3. persistent pain.
4. an unusual smell.
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Fish hard, stay comfortable.
Image caption appears here
Add your deal, information or promotional text
Silverman's Mo-Joo Minnow Brown/Tan #4
This craft fur Clouser has a ton of movement as it falls. Can also bump it over sand.
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News and Information
Women and Sleep: Tips for Getting Your Best Rest
A lot of women struggle to get a good night’s sleep. Not only does good sleep help you approach each day refreshed, but getting enough sleep can help you stay healthy, reduce stress and lower your risk for serious health issues like heart disease. Try these tips to ensure you get a good night’s sleep, every night.
Eat Light
If you're struggling to sleep, evaluate your evening meals. If you eat a heavy meal, digestion is likely to take longer and could disrupt your rest. Choose something with lots of vegetables, lean meats and whole grains to end your day.
Bedtime routines are not just for children. Establishing one for yourself is just as important. Going to bed at the same time every night helps your body naturally know when to relax. And adding things like comfy pajamas, a white noise machine and a consistent skin care regimen can help send the signal to your brain that it's time to wind down.
In addition to going to bed at the same time, create a relaxation routine. Before getting into bed, try taking a warm shower or bath, practice deep breathing or read a book. Over time, these activities will signal your body to know that it's time for rest and ultimately, sleep.
Avoid "Blue" Light
Electronics such as TVs, reading devices, cell phones and computers all emit light that can disrupt the body's natural sleep and wake cycles. If you find that falling asleep is consistently difficult, try removing these sources of light at least 30 minutes before closing your eyes.
Keep it Cool
A cool environment is actually more conducive to rest than a warm one. Adjust your air conditioning at night and keep your room temperature below 70 degrees Fahrenheit. During menstrual cycles, the body's temperature rises, so it may be necessary to adjust even further.
Avoid Alcohol
Sure, alcohol will make you drowsy. But it doesn't help you stay asleep and in fact, can disrupt the body's natural sleep cycle. Instead, try a decaffienated cup of tea, hot cocoa or warm milk.
Still having issues falling and staying asleep? Talk to your primary care provider or your OBGYN. Looking for a women's health professional? Let us help you. Visit our website to find one of our caring experts, ready to help look after you so you can look after everyone else:
Categories: Health
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16-Mar-2018 - Ecole Polytechnique Fédérale de Lausanne (EPFL)
Removing heavy metals from water
According to the World Health Organization almost 1 billion people do not have access to clean drinking water, and that number is expected to increase with climate change. Meanwhile, our endlessly rising energy needs and use of heavy metals in industrial processes have maximized our exposure to toxic materials in water.
Current commercial methods to remove heavy metals including lead from municipal drinking water tend to be costly and energy-consuming, without being sufficiently efficient. Less conventional approaches might be more efficient, but are single-use, difficult to regenerate, or produce significant toxic waste as a side-product.
Now, the lab of Professor Wendy Lee Queen at EPFL, with colleagues at the University of California Berkeley and Lawrence Berkeley National Laboratory have found a solution using metal organic frameworks (MOFs), which are materials made up of metal nodes interlinked by organic chemical 'struts'. Their unprecedented internal surface areas and easy chemical tunability allow MOFs to "pull" water vapor and other gases from air. These same features make them promising materials also for selectively removing heavy metals from water.
A PhD student at EPFL-Valais, Daniel T. Sun, has designed a water-stable MOF/polymer composite using cheap, environmentally and biologically friendly materials. The scientists treated a MOF, known as Fe-BTC, with dopamine, which polymerized to polydopamine (PDA) pinning the polymer inside the MOF. The final composite, named Fe-BTC/PDA, can quickly and selectively remove high amounts of heavy metals like lead and mercury from real-world water samples. In fact, it can remove over 1.6 times its own weight of mercury and 0.4 times of its weight of lead.
Fe-BTC/PDA was then tested in solutions as toxic as some of the worst water samples found in Flint, Michigan. The tests showed that the MOF can, in a matter of seconds, reduce lead concentrations to 2 parts per billion, a level that the U.S. Environmental Protection Agency and World Health Organization deem drinkable.
The scientists also removed lead from various real-world water samples obtained from the Rhone River, the Mediterranean Sea, and a wastewater treatment plant in Switzerland. They also showed how the material could be regenerated easily.
There are multiple sources of exposure to toxic heavy metals. For example, lead is used in paint, ceramic glazes, jewelry, toys, and pipes. Considering this, the approach with the new MOF shows much promise for solving current limitations of water-cleaning systems. The authors of the study are now testing other new specially designed MOFs to remove other types of trace contaminants in water and air.
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is such a pretty word.
A whisper of inky twilight,
a crescent of a dream.
It sounds like a rabbit
hiding in the underbrush.
It sounds like Sylvia Plath
and her instrumental words.
It sounds like a pair
of long white hands brushing,
just barely and too, too gently,
on a starched, stiffened shirt.
It's not enough this word.
It slips you a glimmer of
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reflecting on tranquil waters,
and then...
just as the climax comes,
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and leaves you with the
gentle thud of memories.
Wysteria is a woman.
The type of woman who
sneaks away before dawn
has awoken, while the night
is still crazy with neons.
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history test
Which United States president began the tradition of the State of the Union address?
James Madison
Woodrow Wilson
Thomas Jefferson
George Washington
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2. 👎
3. 👁
1. why no help? plz my peoples?
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2. please
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3. i beg of you peoples
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4. George Washington I think
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5. yall its George Washington 😊👌
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Nervous and Muscular System
Nervous and Muscular System
Central Nervous System: Brain
During development, the CNS forms from a long tube. As the anterior part of the tube, which becomes the brain, folds during its continuing formation, initially three different regions become apparent, identified as the forebrain, midbrain, and hindbrain. These regions continue to develop, forming subdivisions. The forebrain develops into two major subdivisions, the cerebrum and the diencephalon. The midbrain remains as a single major division. The hindbrain develops into three parts: the pons, medulla oblongata, and the cerebellum. The pons, medulla oblongata, and the midbrain are heavily interconnected and share many similar functions; for that reason and their anatomical location, they are considered together as the brainstem. The brain also contains four interconnected cavities, the cerebral ventricles, which are filled with fluid and which provide support for the brain.
Forebrain: The Cerebrum
The larger component of the forebrain, the cerebrum, consists of the right and left cerebral hemispheres as well as some associated structures on the underside of the brain. The cerebral hemispheres consist of the cerebral cortex—an outer shell of gray matter composed primarily of cell bodies that give the area a gray appearance–and an inner layer of white matter, composed primarily of myelinated fiber tracts. The cerebral cortex in turn overlies cell clusters, which are also gray matter and are collectively termed the subcortical nuclei. The fiber tracts consist of the many nerve fibers that bring information into the cerebrum, carry information out, and connect different areas within a hemisphere. The cortex layers of the left and right cerebral hemispheres, although largely separated by a deep longitudinal division, are connected by a massive bundle of nerve fibers known as the corpus callosum.
Cerebral Cortex The cerebral cortex of each cerebral hemisphere is divided into four lobes, named after the overlying skull bones covering the brain: the frontal, parietal, occipital, and temporal lobes. Although it averages only 3 mm in thickness, the cerebral cortex is highly folded. This results in an area containing cortical neurons that is four times larger than it would be without folding, yet does not appreciably increase the volume of the brain. This folding also results in the characteristic external appearance of the human cerebrum, with its sinuous ridges called gyri (singular, gyrus) separated by grooves called sulci (singular, sulcus). The cells of the human cerebral cortex are organized in six distinct layers, composed of varying sizes and numbers of two basic types: pyramidal cells (named for the shape of their cell bodies) and nonpyramidal cells. The pyramidal cells form the major output cells of the cerebral cortex, sending their axons to other parts of the cortex and to other parts of the CNS. Nonpyramidal cells are mostly involved in receiving inputs into the cerebral cortex and in local processing of information. This elaboration of the human cerebral cortex into multiple cell layers, like its highly folded structure, allows for an increase in the number and integration of neurons for signal processing. Such specialization of structural surface area to enhance function in organs throughout the body affirms the general principle of physiology that structure and function are related. This is supported by the fact that an increase in the number of cell layers in the cerebral cortex has paralleled the increase in behavioral and cognitive complexity in vertebrate evolution. For example, reptiles have just three layers in the cortex, and dolphins have five. Some regions of the human brain with ancient evolutionary origins, such as the olfactory cortex, persist in having only three cell layers.
The cerebral cortex is one of the most complex integrating areas of the nervous system. It is here that basic afferent information is collected and processed into meaningful perceptual images, and control over the systems that govern the movement of the skeletal muscles is refined. Nerve fibers enter the cerebral cortex predominantly from the diencephalon and areas of the brainstem; there is also extensive signaling between areas within the cerebral cortex. Some of the input fibers convey information about specific events in the environment, whereas others control levels of cortical excitability, determine states of arousal, and direct attention to specific stimuli.
Basal Nuclei The subcortical nuclei are heterogeneous groups of gray matters that lie deep within the cerebral hemispheres. Predominant among them are the basal nuclei (often, but less correctly referred to as basal ganglia), which have an important function in controlling movement and posture and in more complex aspects of behavior.
Limbic System Thus far, we have described discrete anatomical areas of the forebrain. Some of these forebrain areas, consisting of both gray and white matter, are also classified together in a functional system called the limbic system. This interconnected group of brain structures includes portions of frontal-lobe cortex, temporal lobe, thalamus, and hypothalamus, as well as the fiber pathways that connect them. Besides being connected with each other, the parts of the limbic system connect with many other parts of the CNS. Structures within the limbic system are associated with learning, emotional experience and behavior, and a wide variety of visceral and endocrine functions.
Forebrain: The Diencephalon
The diencephalon, which is divided in two by the narrow third cerebral ventricle, is the second component of the forebrain. It contains the thalamus, hypothalamus, and epithalamus. The thalamus is a collection of several large nuclei that serve as synaptic relay stations and important integrating centers for most inputs to the cortex, and it has a key function in general arousal. The thalamus also is involved in focusing attention. For example, it is responsible for filtering out extraneous sensory information such as might occur when you try to concentrate on a private conversation at a loud, crowded party. The hypothalamus lies below the thalamus and is on the undersurface of the brain; like the thalamus, it contains numerous different nuclei. These nuclei and their pathways form the master command center for neural and endocrine coordination. Indeed, the hypothalamus is the single most important control area for homeostatic regulation of the internal environment. Behaviors having to do with preservation of the individual (for example, eating and drinking) and preservation of the species (reproduction) are among the many functions of the hypothalamus. The hypothalamus
lies directly above and is connected by a stalk to the pituitary gland, an important endocrine structure that the hypothalamus regulates. As mentioned earlier, some parts of the hypothalamus and thalamus are also considered part of the limbic system. The epithalamus is a small mass of tissue that includes the pineal gland, which participates in the control of circadian rhythms through release of the hormone melatonin.
Hindbrain: The Cerebellum
The cerebellum consists of an outer layer of cells, the cerebellar cortex (do not confuse this with the cerebral cortex), and several deeper cell clusters. Although the cerebellum does not initiate voluntary movements, it is an important center for coordinating movements and for controlling posture and balance. To carry out these functions, the cerebellum receives information from the muscles and joints, skin, eyes, vestibular apparatus, viscera, and the parts of the brain involved in control of movement. Although the cerebellum’s function is almost exclusively motor, recent research strongly suggests that it also may be involved in some forms of learning. The other components of the hindbrain—the pons and medulla oblongata—are considered together with the midbrain.
Brainstem: The Midbrain, Pons, and Medulla Oblongata
All the nerve fibers that relay signals between the forebrain, cerebellum, and spinal cord pass through the brainstem. Running through the core of the brainstem and consisting of loosely arranged nuclei intermingled with bundles of axons is the reticular formation, the one part of the brain absolutely essential for life. It receives and integrates input from all regions of the CNS and processes a great deal of neural information. The reticular formation is involved in motor functions, cardiovascular and respiratory control, and the mechanisms that regulate sleep and wakefulness and that focus attention. Most of the biogenic amine neurotransmitters are released from the axons of cells in the reticular formation. Because of the far-reaching projections of these cells, these neurotransmitters affect all levels of the nervous system.
The pathways that convey information from the reticular formation to the upper portions of the brain stimulate arousal and wakefulness. They also direct attention to specific events by selectively stimulating neurons in some areas of the brain while inhibiting others. The fibers that descend from the reticular formation to the spinal cord influence activity in both efferent and afferent neurons. Considerable interaction takes place between the reticular pathways that go up to the forebrain, down to the spinal cord, and to the cerebellum. For example, all three components function in controlling muscle activity. The reticular formation encompasses a large portion of the brainstem, and many areas within the reticular formation serve distinct functions. For example, some reticular formation neurons are clustered together, forming brainstem nuclei and integrating centers. These include the cardiovascular, respiratory, swallowing, and vomiting centers. The reticular formation also has nuclei important in eye-movement control and the reflexive orientation of the body in space. In addition, the brainstem contains nuclei involved in processing information for 10 of the 12 pairs of cranial nerves. These are the peripheral nerves that connect directly with the brain and innervate the muscles, glands, and sensory receptors of the head, as well as many organs in the thoracic and abdominal cavities.
Central Nervous System: Spinal Cord
The spinal cord lies within the bony vertebral column. It is a slender cylinder of soft tissue about as big around as your little finger. The central butterfly-shaped area (in cross section) of gray matter is composed of interneurons, the cell bodies and dendrites of efferent neurons, the entering axons of afferent neurons, and glial cells. The regions of gray matter projecting toward the back of the body are called the dorsal horns, whereas those oriented toward the front are the ventral horns. The gray matter is surrounded by white matter, which consists of groups of myelinated axons. These groups of fiber tracts run longitudinally through the cord, some descending to relay information from the brain to the spinal cord, others ascending to transmit information to the brain. Pathways also transmit information between different levels of the spinal cord. Groups of afferent fibers that enter the spinal cord from the peripheral nerves enter on the dorsal side of the cord via the dorsal roots. Small bumps on the dorsal roots, the dorsal root ganglia, contain the cell bodies of these afferent neurons. The axons of
efferent neurons leave the spinal cord on the ventral side via the ventral roots. A short distance from the cord, the dorsal and ventral roots from the same level combine to form a spinal nerve, one on each side of the spinal cord, carrying two-way information from afferents and efferents.
Peripheral Nervous System
Neurons in the PNS transmit signals between the CNS and receptors and effectors in all other parts of the body. As noted earlier, the axons are grouped into bundles called nerves. The PNS has 43 pairs of nerves: 12 pairs of cranial nerves and 31 pairs of spinal nerves that connect with the spinal cord. The 31 pairs of spinal nerves are designated by the vertebral levels from which they exit: cervical, thoracic, lumbar, sacral, and coccygeal. Neurons in the spinal nerves at each level generally communicate with nearby structures, controlling muscles and glands as well as receiving sensory input. The eight pairs of cervical nerves innervate the
neck, shoulders, arms, and hands. The 12 pairs of thoracic nerves are associated with the chest and upper abdomen. The five pairs of lumbar nerves are associated with the lower abdomen, hips, and legs; the five pairs of sacral nerves are associated with the genitals and lower digestive tract. A single pair of coccygeal nerves associated with the skin over the region of the tailbone brings the total to 31 pairs. These peripheral nerves can contain nerve fibers that are the axons of efferent neurons, afferent neurons, or both. Therefore, fibers in a nerve may be classified as belonging to the efferent or the afferent division of the PNS. All the spinal nerves contain both afferent and efferent fibers, whereas some of the cranial nerves contain only afferent fibers (the optic nerves from the eyes, for example) or only efferent fibers (the hypoglossal nerve to muscles of the tongue, for example). As noted earlier, afferent neurons convey information from sensory receptors at their peripheral endings to the CNS. The long part of their axon is outside the CNS and is part of the PNS. Afferent neurons are sometimes called primary afferents or firstorder neurons because they are the first cells entering the CNS in the synaptically linked chains of neurons that handle incoming information. Efferent neurons carry signals out from the CNS to muscles, glands, and other tissues. The efferent division of the PNS is more complicated than the afferent, being subdivided into a somatic nervous system and an autonomic nervous system. These terms are somewhat misleading because they suggest the presence of additional nervous systems distinct from the central and peripheral systems. Keep in mind that these terms together make up the efferent division of the PNS.
The simplest distinction between the somatic and autonomic systems is that the neurons of the somatic division innervate skeletal muscle, whereas the autonomic neurons innervate smooth and cardiac muscle, glands, neurons in the gastrointestinal tract, and other tissues. The somatic portion of the efferent division of the PNS is made up of all the nerve fibers going from the CNS to skeletal muscle cells. The cell bodies of these neurons are located in groups in the brainstem or the ventral horn of the spinal cord. Their large-diameter, myelinated axons leave the CNS and pass without any synapses to skeletal muscle cells. The neurotransmitter these neurons release is acetylcholine. Because activity in the somatic neurons leads to contraction of the innervated skeletal muscle cells, these neurons are called motor neurons. Excitation of motor neurons leads only to the contraction of skeletal muscle cells; there are no somatic neurons that inhibit skeletal muscles. Muscle relaxation involves the inhibition of the motor neurons in the spinal cord.
Cranial nerves
I. Olfactory
Carries input from receptors in olfactory (smell) neuroepithelium*
II. Optic
Carries input from receptors in eye*
III. Oculomotor
Efferent Afferent
Innervates skeletal muscles that move eyeball up, down, and medially, and raise upper eyelid; innervates smooth muscles that constrict pupil and alter lens shape for near and far vision Transmits information from receptors in muscles
IV. Trochlear
Innervates skeletal muscles that move eyeball downward and laterally
Transmits information from receptors in muscles
V. Trigeminal
Innervates skeletal chewing muscles
Transmits information from receptors in skin; skeletal muscles of face, nose, and mouth; and teeth sockets
VI. Abducens
Innervates skeletal muscles that move eyeball laterally
Transmits information from receptors in muscles
VII. Facial
Efferent Afferent
Innervates skeletal muscles of facial expression and swallowing; innervates nose, palate, and lacrimal and salivary glands Transmits information from taste buds in front of tongue and mouth
VIII. Vestibulocochlear
Transmits information from receptors in inner ear
IX. Glossopharyngeal
Efferent Afferent
Innervates skeletal muscles involved in swallowing and parotid salivary gland Transmits information from taste buds at back of tongue and receptors in auditory-tube skin; also transmits information from carotid artery baroreceptors (blood pressure receptors) and from chemoreceptors that detect changes in blood gas levels
X. Vagus
Efferent Afferent
Innervates skeletal muscles of pharynx and larynx and smooth muscle and glands of thorax and abdomen Transmits information from receptors in thorax and abdomen
XI. Accessory
Innervates sternocleidomastoid and trapezius muscles in the neck
XII. Hypoglossal
Innervates skeletal muscles of tongue
*The olfactory and optic pathways are CNS structures so are not technically “nerves.”
cases, however, the action potentials stop at the axon terminal, where they stimulate the release of a chemical neurotransmitter that affects the next cell. A synapse is the functional connection between a neuron and a second cell. In the CNS, this other cell is also a neuron. In the PNS, the other cell may be either a neuron or an effector cell within a muscle or gland. Although the physiology of neuron-neuron synapses and neuron-muscle synapses is similar, the latter synapses are often called myoneural, or neuromuscular, junctions.
Neuron-neuron synapses usually involve a connection between the axon of one neuron and the dendrites, cell body, or axon of a second neuron. These are called, respectively, axodendritic, axosomatic, and axoaxonic synapses. In almost all synapses, transmission is in one direction only—from the axon of the first (or presynaptic) neuron to the second (or postsynaptic) neuron. Most commonly, the synapse occurs between the axon of the presynaptic neuron and the dendrites or cell body of the postsynaptic neuron. In the early part of the twentieth century, most physiologists believed that synaptic transmission was electrical —that is, that action potentials were conducted directly from one cell to the next. This was a logical assumption, given that nerve endings appeared to touch the postsynaptic cells and that the delay in synaptic conduction was extremely short (about 0.5 msec). Improved histological techniques, however, revealed tiny gaps in the synapses, and experiments demonstrated that the actions of autonomic nerves could be duplicated by certain chemicals. This led to the hypothesis that synaptic transmission might be chemical —that the presynaptic nerve endings might release chemicals called neurotransmitters that stimulated action potentials in the postsynaptic cells.
In 1921 a physiologist named Otto Loewi published the results of experiments suggesting that synaptic transmission was indeed chemical, at least at the junction between a branch of the vagus nerve and the heart. He had isolated the heart of a frog and, while stimulating the branch of the vagus that innervates the heart, perfused the heart with an isotonic salt solution. Stimulation of the vagus nerve was known to slow the heart rate. After stimulating the vagus nerve to this frog heart, Loewi collected the isotonic salt solution and then gave it to a second heart. The vagus nerve to this second heart was not stimulated, but the isotonic solution from the first heart caused the second heart to also slow its beat. Loewi concluded that the nerve endings of the vagus must have released a chemical—which he called Vagusstoff - that inhibited the heart rate. This chemical was subsequently identified as acetylcholine, or ACh. In the decades following Loewi’s discovery, many other examples of chemical synapses were discovered, and the theory of electrical synaptic transmission fell into disrepute. More recent evidence, ironically, has shown that electrical synapses do exist in the nervous system (though they are the exception), within smooth muscles, and between cardiac cells in the heart.
Electrical Synapses: Gap Junctions
In order for two cells to be electrically coupled, they must be approximately equal in size and they must be joined by areas of contact with low electrical resistance. In this way, impulses can be regenerated from one cell to the next without interruption. Adjacent cells that are electrically coupled are joined together by gap junctions. In gap junctions, the membranes of the two cells are separated by only 2 nanometers (1 nano meter = 10 − 9 meter). A surface view of gap junctions in the electron microscope reveals hexagonal arrays of particles that function as channels through which ions and molecules may pass from one cell to the next. Each gap junction is now known to be composed of 12 proteins known as connexins, which are arranged like staves of a barrel to form a water-filled pore.
Gap junctions are present in cardiac muscle, where they allow action potentials to spread from cell to cell, so that the myocardium can contract as a unit. Similarly, gap junctions in some smooth muscles allow many cells to be stimulated and contract together, producing a stronger contraction (as in the uterus during labor). The function of gap junctions in the nervous system is less well understood; nevertheless, gap junctions are found between neurons in the brain, where they can synchronize the firing of groups of neurons. Gap junctions are also found between neuroglial cells, where they are believed to allow the passage of Ca 2 + and perhaps other ions and molecules between the connected cells. The function of gap junctions is more complex than was once thought. Neurotransmitters and other stimuli, acting through second messengers such as cAMP or Ca 2 +, can lead to the phosphorylation or dephosphorylation of gap junction connexin proteins, causing the opening or closing of gap junction channels. For example, light causes the ion conductance through the gap junctions between neurons in the retina to increase in some neurons and decrease in others.
Chemical Synapses
Transmission across the majority of synapses in the nervous system is one-way and occurs through the release of chemical neurotransmitters from presynaptic axon endings. These presynaptic endings, called terminal boutons (from the Middle French bouton = button) because of their swollen appearance, are separated from the postsynaptic cell by a synaptic cleft so narrow (about 10 nm) that it can be seen clearly only with an electron microscope.
Chemical transmission requires that the synaptic cleft stay very narrow and that neurotransmitter molecules are released near their receptor proteins in the postsynaptic membrane. The physical association of the pre- and postsynaptic membranes at the chemical synapse is stabilized by the action of particular membrane proteins. Cell adhesion molecules (CAMs) are proteins in the pre- and postsynaptic membranes that project from these membranes into the synaptic cleft, where they bond to each other. This Velcro-like effect ensures that the pre- and postsynaptic membranes stay in close proximity for rapid chemical transmission.
Release of Neurotransmitter
Neurotransmitter molecules within the presynaptic neuron endings are contained within many small, membrane-enclosed synaptic vesicles. In order for the neurotransmitter within these vesicles to be released into the synaptic cleft, the vesicle membrane must fuse with the axon membrane in the process of exocytosis. Exocytosis of synaptic vesicles, and the consequent release of neurotransmitter molecules into the synaptic cleft, is triggered by action potentials that stimulate the entry of Ca2+ into the axon terminal through voltage-gated Ca2+ channels. When there is a greater frequency of action potentials at the axon terminal, there is a greater entry of Ca2+, and thus a larger number of synaptic vesicles undergoing exocytosis and releasing neurotransmitter molecules. As a result, a greater frequency of action potentials by the presynaptic axon will result in greater stimulation of the postsynaptic neuron. Ca2+ entering the axon terminal binds to a protein, believed to be synaptotagmin, which serves as a Ca2+ sensor, forming a Ca 2 + -synaptotagmin complex in the cytoplasm. This occurs close to the location where synaptic vesicles are already docked (attached) to the plasma membrane of the axon terminal. At this stage, the docked vesicles are bound to the plasma membrane of the presynaptic axon by complexes of three SNARE proteins that bridge the vesicles and plasma membrane. The complete fusion of the vesicle membrane and plasma membrane, and the formation of a pore that allows the release of neurotransmitter, occurs when the Ca2+ -synaptotagmin complex displaces a component of the SNARE, or fusion, complex. This process is very rapid: exocytosis of neurotransmitter occurs less than 100 microseconds after the intracellular Ca 2 + concentration rises (SNARE- Soluble NSF Attachment protein Receptor; NSF – N-ethyl maleimide Sensitive Factor).
Action of Neurotransmitter
Once the neurotransmitter molecules have been released from the presynaptic axon terminals, they diffuse rapidly across the synaptic cleft and reach the membrane of the postsynaptic cell. The neurotransmitters then bind to specific receptor proteins that are part of the postsynaptic membrane. Receptor proteins have high specificity for their neurotransmitter, which is the ligand of the receptor protein. The term ligand in this case refers to a smaller molecule (the neurotransmitter) that binds to and forms a complex with a larger protein molecule (the receptor). Binding of the neurotransmitter ligand to its receptor protein causes ion channels to open in the postsynaptic membrane. The gates that regulate these channels, therefore, can be called chemically regulated (or ligand-regulated) gates because they open in response to the binding of a chemical ligand to its receptor in the postsynaptic plasma membrane.
The nervous system is composed of neurons, which produce and conduct electrochemical impulses, and supporting cells, which assist the functions of neurons. Neurons are classified functionally and structurally; the various types of supporting cells perform specialized functions.
Although neurons vary considerably in size and shape, they generally have three principal regions: (1) a cell body, (2) dendrites, and (3) an axon. Dendrites and axons can be referred to generically as processes, or extensions from the cell body. The cell body is the enlarged portion of the neuron that contains the nucleus. It is the “nutritional center” of the neuron where macromolecules are produced. The cell body and larger dendrites (but not axons) contain Nissl bodies, which are seen as dark-staining granules under the microscope. Nissl bodies are composed of large stacks of rough endoplasmic reticulum that are needed for the synthesis of membrane proteins. The cell bodies within the CNS are frequently clustered into groups called nuclei (not to be confused with the nucleus of a cell). Cell bodies in the PNS usually occur in clusters called ganglia.
Dendrites (from the Greek dendron = tree branch) are thin, branched processes that extend from the cytoplasm of the cell body. Dendrites provide a receptive area that transmits graded electrochemical impulses to the cell body. The axon is a longer process that conducts impulses, called action potentials, away from the cell body. Axons vary in length from only a millimeter long to up to a meter or more (for those that extend from the CNS to the foot). The origin of the axon near the cell body is an expanded region called the axon hillock; it is here that action potentials originate. Side branches called axon collaterals may extend from the axon. Because axons can be quite long, special mechanisms are required to transport organelles and proteins from the cell body to the axon terminals. This axonal transport is energy-dependent and is often divided into a fast component and two slow components. The fast component (at 200 to 400 mm/day) mainly transports membranous vesicles. One slow component (at 0.2 to 1 mm/day) transports microfilaments and microtubules of the cytoskeleton, while the other slow component (at 2 to 8 mm/day) transports over 200 different proteins, including those critical for synaptic function. The slow components appear to transport their cargo in fast bursts with frequent pauses, so that the overall rate of transport is much slower than that occurring in the fast component. Axonal transport may occur from the cell body to the axon and dendrites. This direction is called anterograde transport, and involves molecular motors of kinesin proteins that move cargo along the microtubules of the cytoskeleton. For example, kinesin motors move synaptic vesicles, mitochondria, and ion channels from the cell body through the axon. Similar anterograde transport occurs in the dendrites, as kinesin moves postsynaptic receptors for neurotransmitters and ion channels along the microtubules in the dendrites.
By contrast, axonal transport in the opposite direction-that is, along the axon and dendrites toward the cell body-is known as retrograde transport and involves molecular motor proteins of dyneins. The dyneins move membranes, vesicles, and various molecules along microtubules of the cytoskeleton toward the cell body of the neuron. Retrograde transport can also be responsible for movement of herpes virus, rabies virus, and tetanus toxin from the nerve terminals into cell bodies.
Classification of Neurons and Nerves
Neurons may be classified according to their function or structure. The functional classification is based on the direction in which they conduct impulses. Sensory, or afferent, neurons conduct impulses from sensory receptors into the CNS. Motor, or efferent, neurons conduct impulses out of the CNS to effector organs (muscles and glands). Association neurons, or interneurons, are located entirely within the CNS and serve the associative, or integrative, functions of the nervous system. There are two types of motor neurons: somatic and autonomic. Somatic motor neurons are responsible for both reflex and voluntary control of skeletal muscles. Autonomic motor neurons innervate (send axons to) the involuntary effectors—smooth muscle, cardiac muscle, and glands. The cell bodies of the autonomic neurons that innervate these organs are located outside the CNS in autonomic ganglia. There are two subdivisions of autonomic neurons: sympathetic and parasympathetic. Autonomic motor neurons, together with their central control centers, constitute the autonomic nervous system. The structural classification of neurons is based on the number of processes that extend from the cell body of the neuron. Pseudounipolar neurons have a single short process that branches like a T to form a pair of longer processes. They are called pseudounipolar (from the Late Latin pseudo = false) because, although they originate with two processes, during early embryonic development their two processes converge and partially fuse. Sensory neurons are pseudounipolar—one of the branched processes receives sensory stimuli and produces nerve impulses; the other delivers these impulses to synapses within the brain or spinal cord. Anatomically, the part of the process that conducts impulses toward the cell body can be considered a dendrite, and the part that conducts impulses away from the cell body can be considered an axon. Functionally, however, the branched process behaves as a single, long axon that continuously conducts action potentials (nerve impulses). Only the small projections at the receptive end of the process function as typical dendrites, conducting graded electrochemical impulses rather than action potentials. Bipolar neurons have two processes, one at either end; this type is found in the retina of the eye. Multipolar neurons, the most common type, have several dendrites and one axon extending from the cell body; motor neurons are good examples of this type.
A nerve is a bundle of axons located outside the CNS. Most nerves are composed of both motor and sensory fibers and are thus called mixed nerves. Some of the cranial nerves, however, contain sensory fibers only. These are the nerves that serve the special senses of sight, hearing, taste, and smell. A bundle of axons in the CNS is called a tract.
Supporting Cells
Unlike other organs that are “packaged” in connective tissue derived from mesoderm (the middle layer of embryonic tissue), most of the supporting cells of the nervous system are derived from the same embryonic tissue layer (ectoderm) that produces neurons. The term neuroglia (or glia) traditionally refers to the supporting cells of the CNS, but in current usage the supporting cells of the PNS are often also called glial cells.
There are two types of supporting cells in the peripheral nervous system:
1. Schwann cells (also called neurolemmocytes), which form myelin sheaths around peripheral axons; and
2. Satellite cells, or ganglionic gliocytes, which support neuron cell bodies within the ganglia of the PNS.
There are four types of supporting cells in the central nervous system:
1. Oligodendrocytes, which form myelin sheaths around axons of the CNS;
2. Microglia, which migrate through the CNS and phagocytose foreign and degenerated material;
3. Astrocytes, which help to regulate the external environment of neurons in the CNS; and
4. Ependymal cells, which line the ventricles (cavities) of the brain and the central canal of the spinal cord.
Microglia are of hematopoietic (bone marrow) origin, and indeed can be replenished by monocytes (a type of leukocyte) from the blood. They remove toxic debris within the brain and secrete anti-inflammatory factors, functions that are essential for the health of neurons. Yet their actions have a negative side; overactive microglial cells can release free radicals that promote oxidative stress. and thereby contribute to neurodegenerative diseases.
Neurotransmitters and Neuromodulators
Neurons are often referred to using the suffix -ergic; the missing prefix is the type of neurotransmitter the neuron releases. For example, dopaminergic applies to neurons that release the neurotransmitter dopamine (EPSPs – Excitatory Post Synaptic Potentials or IPSPs – Inhibitory Post Synaptic Potentials). Neurotransmitters are the agents which are responsible for nerve impulse transmission. Neuromodulators are the agents which are responsible for complex role as neurotransmitter, paracrine factor, and hormone etc.. They are acting both in sympathetic and parasympathetic neurons.
Acetylcholine (ACh) is a major neurotransmitter in the PNS at the neuromuscular junction and in the brain. Neurons that release ACh are called cholinergic neurons. The cell bodies of the brain’s cholinergic neurons are concentrated in relatively few areas, but their axons are widely distributed. Acetylcholine is synthesized from choline (a common nutrient found in many foods) and acetyl coenzyme A in the cytoplasm of synaptic terminals and stored in synaptic vesicles. After it is released and activates receptors on the postsynaptic membrane, the concentration of ACh at the postsynaptic membrane decreases (thereby stopping receptor activation) due to the action of the enzyme acetylcholinesterase. This enzyme is located on the presynaptic and postsynaptic membranes and rapidly destroys ACh, releasing choline and acetate. The choline is then transported back into the presynaptic axon terminals where it is reused in the synthesis of new ACh. Some chemical weapons, such as the nerve gas Sarin, inhibit acetylcholinesterase, causing a buildup of ACh in the synaptic cleft. This results in overstimulation of postsynaptic ACh receptors, initially causing uncontrolled muscle contractions but ultimately leading to receptor desensitization and paralysis.
There are two general types of ACh receptors, and they are distinguished by their responsiveness to two different chemicals. Nicotinic Acetylcholine Receptors Recall that although a receptor is considered specific for a given ligand, such as ACh, most receptors will recognize natural or synthetic compounds that exhibit some degree of chemical similarity to that ligand. Some ACh receptors respond not only to acetylcholine but to the compound nicotine and have therefore come to be known as nicotinic receptors. Nicotine is a plant alkaloid compound that constitutes 1% to 2% of tobacco products. It is also contained in treatments for smoking cessation, such as nasal sprays, chewing gums, and transdermal patches. Nicotine’s hydrophobic structure allows rapid absorption through lung capillaries, mucous membranes, skin, and the blood–brain barrier. The nicotinic acetylcholine receptor is an excellent example of a receptor that contains an ion channel (i.e., a ligand-gated ion channel). In this case, the channel is permeable to both sodium and potassium ions, but because Na+ has the larger electrochemical driving force, the net effect of opening these channels is depolarization. Nicotinic receptors are present at the neuromuscular junction and, several nicotinic receptor antagonists are toxins that induce paralysis. Nicotinic receptors in the brain are important in cognitive functions and behavior. For example, one cholinergic system that employs nicotinic receptors has a major function in attention, learning, and memory by reinforcing the ability to detect and respond to meaningful stimuli. The presence of nicotinic receptors on presynaptic terminals in reward pathways of the brain explains why tobacco products are among the most highly addictive substances known.
Muscarinic Acetylcholine Receptors The other general type of cholinergic receptor is stimulated not only by acetylcholine but by muscarine, a poison contained in some mushrooms; therefore, these are called muscarinic receptors. These receptors are metabotropic and couple with G proteins, which then alter the activity of a number of different enzymes and ion channels. They are prevalent at some cholinergic synapses in the brain and at junctions where a major division of the PNS innervates peripheral glands, tissues, and organs, like salivary glands, smooth muscle cells, and the heart. Atropine is a naturally occuring antagonist of muscarinic receptors with many clinical uses, such as in eyedrops that relax the smooth muscles of the iris, thereby dilating the pupils for an eye exam.
Biogenic Amines
The biogenic amines are small, charged molecules that are synthesized from amino acids and contain an amino group (R}NH2). The most common biogenic amines are dopamine, norepinephrine, serotonin, and histamine. Epinephrine, another biogenic amine, is not a common neurotransmitter in the CNS but is the major hormone secreted by the adrenal medulla. Norepinephrine is an important neurotransmitter in both the central and peripheral components of the nervous system.
Catecholamines Dopamine (DA), norepinephrine (NE), and epinephrine all contain a catechol ring (a six-carbon ring with two adjacent hydroxyl groups) and an amine group, which is why they are called catecholamines. The catecholamines are formed from the amino acid tyrosine and share the same two initial steps in their synthetic pathway. Synthesis of catecholamines begins with the uptake of tyrosine by the axon terminals and its conversion to another precursor, L-dihydroxy-phenylalanine (L-dopa) by the rate-limiting enzyme in the pathway, tyrosine hydroxylase. Depending on the enzymes expressed in a given neuron, any one of the three catecholamines may ultimately be released. Autoreceptors on the presynaptic terminals strongly modulate synthesis and release of the catecholamines. After activation of the receptors on the postsynaptic cell, the catecholamine concentration in the synaptic cleft declines, mainly because a membrane transporter protein actively transports the catecholamine back into the axon terminal. The catecholamine neurotransmitters are also broken down in both the extracellular fluid and the axon terminal by enzymes such as monoamine oxidase (MAO). Drugs known as monoamine oxidase (MAO) inhibitors increase the amount of norepinephrine and dopamine in a synapse by slowing their metabolic degradation. Among other things, they are used in the treatment of mood disorders such as some types of depression.
Within the CNS, the cell bodies of the catecholamine releasing neurons lie in the brainstem and hypothalamus. Although these neurons are relatively few in number, their axons branch greatly and go to virtually all parts of the brain and spinal cord. These neurotransmitters have essential functions in states of consciousness, mood, motivation, directed attention, movement, blood pressure regulation, and hormone release. Epinephrine and norepinephrine are also synthesized in the adrenal glands. For historical reasons having to do with nineteenth-century physiologists referring to secretions of the adrenal gland as “adrenaline,” the adjective “adrenergic” is commonly used to describe neurons that release norepinephrine
or epinephrine and also to describe the receptors to which those neurotransmitters bind. There are two major classes of receptors for norepinephrine and epinephrine: alpha-adrenergic receptors (alpha-adrenoceptors) and beta-adrenergic receptors (betaadrenoceptors). All catecholamine receptors are metabotropic, and thus use second messengers to transfer a signal from the surface of the cell to the cytoplasm. Alpha-adrenoceptors exist in two subclasses, a1 and a2. They act presynaptically to inhibit norepinephrine release (a2) or postsynaptically to either stimulate or inhibit the activity of different types of K+ channels (a1). Betaadrenoceptors act via stimulatory G proteins to increase cAMP in the postsynaptic cell. There are three subclasses of beta-receptors, b1, b2, and b3, which function in different ways in different tissues. The subclasses of alpha- and beta-receptors are distinguished by the drugs that influence them and their second-messenger systems.
Serotonin (5-hydroxytryptamine, or 5-HT) is produced from tryptophan, an essential amino acid. Its effects generally have a slow onset, indicating that it works as a neuromodulator. Serotonergic neurons innervate virtually every structure in the brain and spinal cord and operate via at least 16 different receptor subtypes. In general, serotonin has an excitatory effect on pathways that are involved in the control of muscles, and an inhibitory effect on pathways that mediate sensations. The activity of serotonergic neurons is lowest or absent during sleep and highest during states of alert wakefulness. In addition to their contributions to motor activity and sleep, serotonergic pathways also function in the regulation of food intake, reproductive behavior, and emotional states such as mood and anxiety.
Selective serotonin reuptake inhibitors such as paroxetine (Paxil) are thought to aid in the treatment of depression by inactivating the presynaptic membrane 5-HT transporter, which mediates the reuptake of serotonin into the presynaptic cell. This, in turn, increases the synaptic concentration of the neurotransmitter. Interestingly, such drugs are often associated with decreased appetite but paradoxically cause weight gain due to disruption of enzymatic pathways that regulate fuel metabolism. This is one example of how the use of reuptake inhibitors for a specific neurotransmitter—one with widespread actions—can cause unwanted side effects. Serotonin is found in both neural and nonneural cells, with the majority located outside of the CNS. In fact, approximately 90% of the body’s total serotonin is found in the digestive system, 8% is in blood platelets and immune cells, and only 1% to 2% is found in the brain. The drug lysergic acid diethylamide (LSD) stimulates the 5-HT2A subtype of serotonin receptor in the brain. Though the mechanism is not completely understood, alteration of this receptor complex produces the intense visual hallucinations that are produced by ingestion of LSD.
Amino Acid Neurotransmitters
In addition to the neurotransmitters that are synthesized from amino acids, several amino acids themselves function as neurotransmitters. Although the amino acid neurotransmitters chemically fit the category of biogenic amines, they are traditionally placed into a category of their own. The amino acid neurotransmitters are by far the most prevalent neurotransmitters in the CNS, and they affect virtually all neurons there.
Glutamate There are a number of excitatory amino acids, but the most common by far is glutamate, which is estimated to be the primary neurotransmitter at 50% of excitatory synapses in the CNS. As with other neurotransmitters, pharmacological manipulation of the receptors for glutamate has permitted identification of specific receptor subtypes by their ability to bind natural and synthetic ligands. Although metabotropic glutamate receptors do exist, the vast majority are ionotropic, with two important subtypes being found in postsynaptic membranes. They are designated as AMPA receptors (identified by their binding to a-amino-3 hydroxy-5 methyl-4 isoxazole propionic acid) and NMDA receptors (which bind N-methyl-D-aspartate). Cooperative activity of AMPA and NMDA receptors has been implicated in one type of a phenomenon called longterm potentiation (LTP). This mechanism couples frequent activity across a synapse with lasting changes in the strength of signaling across that synapse and is thus thought to be one of the major cellular processes involved in learning and memory.
When a presynaptic neuron fires action potentials (step 1), glutamate is released from presynaptic terminals (step 2) and binds to both AMPA and NMDA receptors on postsynaptic membranes (step 3). AMPA receptors function just like the excitatory postsynaptic receptors discussed earlier—when glutamate binds, the channel becomes permeable to both Na+ and K+, but the larger entry of Na+ creates a depolarizing EPSP of the postsynaptic cell (step 4). By contrast, NMDA-receptor channels also mediate a substantial Ca+ flux, but opening them requires more than just glutamate binding. A magnesium ion blocks NMDA channels when the membrane voltage is near the negative resting potential, and to drive it out of the way the membrane must be significantly depolarized by the current through AMPA channels (step 5). This explains why it requires a high frequency of presynaptic action potentials to complete the longterm potentiation mechanism. At low frequencies, there is insufficient temporal summation of AMPA-receptor EPSPs to provide the 20–30 mV of depolarization needed to move the magnesium ion, and so the NMDA receptors do not open. When the depolarization is sufficient, however, NMDA receptors do open, allowing Ca2+ to enter the postsynaptic cell (step 6). Calcium ions then activate a second-messenger cascade in the postsynaptic cell that includes persistent activation of multiple different protein kinases, stimulation of gene expression and protein synthesis, and ultimately a long-lasting increase in the sensitivity of the postsynaptic neuron to glutamate (step 7). This second-messenger system can also activate long-term enhancement of presynaptic glutamate release via retrograde signals that have not yet been identified (step 8). Each subsequent action potential arriving along this presynaptic cell will cause a greater depolarization of the postsynaptic membrane. Thus, repeatedly and intensely activating a particular pattern of synaptic firing (as you might when studying for an exam) causes chemical and structural changes that facilitate future activity along those same pathways (as might occur when recalling what you learned).
Prior to exocytosis, the synaptic vesicles are filled with neurotransmitter and translocate to the active zone, where they dock at morphologically defined sites on the target plasma membrane. The v-SNARE synaptobrevin/VAMP faces the target plasma membrane, which contains the v-SNAREs SNAP25 and syntaxin, which associates with MUNC18/n-Sec1. During the priming stage of vesicle fusion, the SNARE proteins partially zipper together and complexin clamps the SNARE complex in an activation-poised state to prevent membrane fusion. Action potential–induced calcium influx triggers calcium, phospholipid, and SNARE complex binding by synaptotagmin, which causes displacement of complexin and opening of the fusion pore. Vesicle/target membrane fusion allows neurotransmitter to enter the synaptic cleft and interact with the postsynaptic density of the partner neuron. (vSNARE- Vesicle SNARE; t-SNARE – Target SNARE; Q-SNARE – Gln SNARE; R-SNARE-Arg SNARE; Munc18-Mammalian uncoordinated 18 protein)
During step 1, synaptic vesicles are primed for fusion; this step involves opening of the closed conformation of syntaxin, a switch of the Munc18-binding mode of syntaxin from the closed to the open conformation and partial assembly of trans-SNARE complexes. Step 1 is facilitated by recently discovered chaperones (cysteine string proteins (CSPs) and synucleins) that enhance SNARE complex assembly and whose dysfunction is related to neurodegeneration3. During step 2, the fusion pore opens, with full trans-SNARE complex assembly. During step 3, the fusion pore expands, converting trans-SNARE into cis-SNARE complexes. In step 4, NSF and SNAPs mediate disassembly of the SNARE complex, leading to vesicle recycling. The cycle shown here for synaptic vesicle fusion is paradigmatic for most cytoplasmic fusion reactions, although the details differ. In knockout experiments, deletion of the SM protein Munc18-1 produces the most severe phenotype22, possibly because loss of SNARE components of the fusion machinery is better compensated for than loss of SM proteins. SNAREs are generally classified into four types (R, Qa, Qb and Qc) that assemble into SNARE complexes in an obligatory R-Qa-Qb-Qc combination.
NMDA receptors have also been implicated in mediating excitotoxicity. This is a phenomenon in which the injury or death of some brain cells (due, for example, to blocked or ruptured blood vessels) rapidly spreads to adjacent regions. When glutamate-containing cells die and their membranes rupture, the flood of glutamate excessively stimulates AMPA and NMDA receptors on nearby neurons. The excessive stimulation of those neurons causes the accumulation of toxic concentrations of intracellular Ca2+, which in turn kills those neurons and causes them to rupture, and the wave of damage progressively spreads. Recent experiments and clinical trials suggest that administering NMDA receptor antagonists may help minimize the spread of cell death following injuries to the brain.
GABA GABA (gamma-aminobutyric acid) is the major inhibitory neurotransmitter in the brain. Although it is not one of the 20 amino acids used to build proteins, it is classified with the amino acid neurotransmitters because it is a modified form of glutamate. With few exceptions, GABA neurons in the brain are small interneurons that dampen activity within neural circuits. Postsynaptically, GABA may bind to ionotropic or metabotropic receptors. The ionotropic receptor increases Cl2 flux into the cell, resulting in hyperpolarization (an IPSP) of the postsynaptic membrane. In addition to the GABA binding site, this receptor has several additional binding sites for other compounds, including steroids, barbiturates, and benzodiazepines. Benzodiazepine drugs such as alprazolam (Xanax) and diazepam (Valium) reduce anxiety, guard against seizures, and induce sleep by increasing Cl2 flux through the GABA receptor. Synapses that use GABA are also among the many targets of the ethanol (ethyl alcohol) found in alcoholic beverages. Ethanol stimulates GABA synapses and simultaneously inhibits excitatory glutamate synapses, with the overall effect being global depression of the electrical activity of the brain. Thus, as a person’s blood alcohol content increases, there is a progressive reduction in overall cognitive ability, along with sensory perception inhibition (hearing and balance, in particular), loss of motor coordination, impaired judgment, memory loss, and unconsciousness. Very high doses of ethanol are sometimes fatal, due to suppression of brainstem centers responsible for regulating the circulatory and respiratory systems. Dopaminergic and endogenous opioid signaling pathways (discussed in the next section) are also affected by ethanol, which results in short-term mood elevation or euphoria. The involvement of these pathways underlies the development of long-term alcohol dependence in some people.
Glycine Glycine is the major neurotransmitter released from inhibitory interneurons in the spinal cord and brainstem. It binds to ionotropic receptors on postsynaptic cells that allow Cl2 to enter, thus preventing them from approaching the threshold for firing action potentials. Normal function of glycinergic neurons is essential for maintaining a balance of excitatory and inhibitory activity in spinal cord integrating centers that regulate skeletal muscle contraction. This becomes apparent in cases of poisoning with the neurotoxin strychnine, an antagonist of glycine receptors sometimes used to kill rodents. Victims experience hyperexcitability throughout the nervous system, which leads to convulsions, spastic contraction of skeletal muscles, and ultimately death due to impairment of the muscles of respiration.
The neuropeptides are composed of two or more amino acids linked together by peptide bonds. About 100 neuropeptides have been identified, but their physiological functions are not all known. It seems that evolution has favored the same chemical messengers for use in widely differing circumstances, and many of the neuropeptides have been previously identified in nonneural tissue where they function as hormones or paracrine substances. They generally retain the name they were given when first discovered in the nonneural tissue. The neuropeptides are formed differently than other neurotransmitters, which are synthesized in the axon terminals by very few enzyme-mediated steps. The neuropeptides, in contrast, are derived from large precursor proteins, which in themselves have little, if any, inherent biological activity. The synthesis of these precursors, directed by mRNA, occurs on ribosomes, which exist only in the cell body and large dendrites of the neuron, often a considerable distance from axon terminals or varicosities where the peptides are released. In the cell body, the precursor protein is packaged into vesicles, which are then moved by axonal transport into the terminals or varicosities, where the protein is cleaved by specific peptidases. Many of the precursor proteins contain multiple peptides, which may be different or be copies of one peptide. Neurons that release one or more of the peptide neurotransmitters
are collectively called peptidergic. In many cases, neuropeptides are cosecreted with another type of neurotransmitter and act as neuromodulators. The amount of neuropeptide released from vesicles at synapses is significantly less than the amount of nonpeptidergic neurotransmitters such as catecholamines. In addition, neuropeptides can diffuse away from the synapse and affect other neurons at some distance, in which case they are referred to as neuromodulators.
The actions of these neuromodulators are longer lasting (on the order of several hundred milliseconds) than when neuropeptides or other molecules act as neurotransmitters. After release, neuropeptides can interact with either ionotropic or metabotropic receptors. They are eventually broken down by peptidases located in neuronal membranes. Endogenous opioids—a group of neuropeptides that includes beta-endorphin, the dynorphins, and the enkephalins— have attracted much interest because their receptors are the sites of action of opiate drugs such as morphine and codeine. The opiate drugs are powerful analgesics (that is, they relieve pain without loss of consciousness), and the endogenous opioids undoubtedly have a function in regulating pain. There is also evidence that the opioids function in regulating eating and drinking behavior, circulatory system function, and mood and emotion.
Certain very short-lived gases also serve as neurotransmitters. Nitric oxide is the best understood, but recent research indicates that carbon monoxide and hydrogen sulfide are also emitted by neurons as signals. Gases are not released by exocytosis of presynaptic vesicles, nor do they bind to postsynaptic plasma membrane receptors. They are produced by enzymes in axon terminals (in response to Ca21 entry) and simply diffuse from their sites of origin in one cell into the intracellular fluid of other neurons or effector cells, where they bind to and activate proteins. For example, nitric oxide released from neurons activates guanylyl cyclase in recipient cells. This enzyme increases the concentration of the second-messenger cyclic GMP, which in turn can alter ion channel activity in the postsynaptic cell.
Nitric oxide functions in a bewildering array of neutrally mediated events—learning, development, drug tolerance, penile and clitoral erection, and sensory and motor modulation, to name a few. Paradoxically, it is also implicated in neural damage that results, for example, from the stoppage of blood flow to the brain or from a head injury. In later chapters, we will see that nitric oxide is produced not only in the central and peripheral nervous systems but also by a variety of nonneural cells; for example, it has important paracrine functions in the circulatory and immune systems, among others.
Other nontraditional neurotransmitters include the purines, ATP and adenosine, which act principally as neuromodulators. ATP is present in all presynaptic vesicles and is coreleased with one or more other neurotransmitters in response to Ca2+ influx into the terminal. Adenosine is derived from ATP via enzyme activity occurring in the extracellular compartment. Both presynaptic and postsynaptic receptors have been described for adenosine, and the functions these substances have in the nervous system and other tissues are active areas of research.
Neuroeffector Communication
Many neurons of the PNS end, however, not at synapses on other neurons but at neuroeffector junctions on muscle, gland, and other cells. The neurotransmitters released by these efferent neurons’ terminals or varicosities provide the link by which electrical activity of the nervous system regulates effector cell activity. The events that occur at neuroeffector junctions are similar to those at synapses between neurons. The neurotransmitter is released from the efferent neuron upon the arrival of an action potential at the neuron’s axon terminals or varicosities. The neurotransmitter then diffuses to the surface of the effector cell, where it binds to receptors on that cell’s plasma membrane. The receptors may be directly under the axon terminal or varicosity, or they may be some distance away so that the diffusion path the neurotransmitter follows is long. The receptors on the effector cell may be either ionotropic or metabotropic.
Nerve impulse
The changes in Na+ and K+ diffusion and the resulting changes in the membrane potential they produce constitute an event called the action potential, or nerve impulse. The electrochemical wave that travels along nerve fiber and stimulates muscles, glands or other nerve cells is called as nerve impulse.
Spike Potential
The periodic rise of depolarization wave and rapid fall of repolarization wave are known as spike potential.
All-or-None Law
Once a region of axon membrane has been depolarized to a threshold value, the positive feedback effect of depolarization on Na+ permeability and of Na+ permeability on depolarization causes the membrane potential to shoot toward about +30 mV. It does not normally become more positive than +30 mV because the Na+ channels quickly close and the K+ channels open. The length of time that the Na+ and K+ channels stay open is independent of the strength of the depolarization stimulus. The amplitude (size) of action potentials is therefore all or none. When depolarization is below a threshold value, the voltage-regulated gates are closed; when depolarization reaches threshold, a maximum potential change (the action potential) is produced. Because the change from −70 mV to +30 mV and back to −70 mV lasts only about 3 msec, the image of an action potential on an oscilloscope screen looks like a spike. Action potentials are therefore sometimes called spike potentials. The channels are open only for a fixed period of time because they are soon inactivated, a process different from simply closing the gates. Inactivation occurs automatically and lasts until the membrane has repolarized. Because of this automatic inactivation, all action potentials have about the same duration. Likewise, since the concentration gradient for Na+ is relatively constant, the amplitudes of the action potentials are about equal in all axons at all times (from −70 mV to +30 mV, or about 100 mV in total amplitude).
Conduction of Nerve Impulses
When stimulating electrodes artificially depolarize one point of an axon membrane to a threshold level, voltage-regulated channels open and an action potential is produced at that small region of axon membrane containing those channels. For about the first millisecond of the action potential, when the membrane voltage changes from −70 mV to +30 mV, a current of Na+ enters the cell by diffusion because of the opening of the Na+ gates. Each action potential thus “injects” positive charges (sodium ions) into the axon. These positively charged sodium ions are conducted, by the cable properties of the axon, to an adjacent region that still has a membrane potential of −70 mV. Within the limits of the cable properties of the axon (1 to 2 mm), this helps to depolarize the adjacent region of axon membrane. When this adjacent region of membrane reaches a threshold level of depolarization, it too produces the action potential as its voltage-regulated gates open. The action potential produced at the first location in the axon membrane (usually at the axon hillock) thus serves as the depolarization stimulus for the next region of the axon membrane, which can then produce the action potential. The action potential in this second region, in turn, serves as a depolarization stimulus for the production of the action potential in a third region, and so on. This explains how the action potential is produced at all regions of the axon beyond the initial segment at the axon hillock.
Conduction in an Unmyelinated Axon
In an unmyelinated axon, every patch of membrane that contains Na+ and K+ channels can produce an action potential. Action potentials are thus produced along the entire length of the axon. The cablelike spread of depolarization induced by the influx of Na + during one action potential helps to depolarize the adjacent regions of membrane—a process that is also aided by movements of ions on the outer surface of the axon membrane. This process would depolarize the adjacent membranes on each side of the region to produce the action potential, but the area that had previously produced one cannot produce another at this time because it is still in its refractory period. It is important to recognize that action potentials are not really “conducted,” although it is convenient to use that word. Each action potential is a separate, complete event that is repeated, or regenerated, along the axon’s length. This is analogous to the “wave” performed by spectators in a stadium. One person after another gets up (depolarization) and then sits down (repolarization). It is thus the “wave” that travels (the repeated action potential at different locations along the axon membrane), not the people.
The action potential produced at the end of the axon is thus a completely new event that was produced in response to depolarization from the previous region of the axon membrane. The action potential produced at the last region of the axon has the same amplitude as the action potential produced at the first region. Action potentials are thus said to be conducted without decrement (without decreasing in amplitude). The spread of depolarization by the cable properties of an axon is fast compared to the time it takes to produce an action potential. Thus, the more action potentials along a given stretch of axon that have to be produced, the slower the conduction. Because action potentials must be produced at every fraction of a micrometer in an unmyelinated axon, the conduction rate is relatively slow. This conduction rate is somewhat faster if the unmyelinated axon is thicker, because thicker axons have less resistance to the flow of charges (so conduction of charges by cable properties is faster). The conduction rate is substantially faster if the axon is myelinated, because fewer action potentials are produced along a given length of myelinated axon.
Conduction in a Myelinated Axon
The myelin sheath provides insulation for the axon, preventing movements of Na+ and K+ through the membrane. If the myelin sheath were continuous, therefore, action potentials could not be produced. The myelin thus has interruptions-the nodes of Ranvier, as previously described. Because the cable properties of axons can conduct depolarizations over only a very short distance (1 to 2 mm), the nodes of Ranvier cannot be separated by more than this distance. Studies have shown that Na+ channels are highly concentrated at the nodes (estimated at 10,000 per square micrometer) and almost absent in the regions of axon membrane between the nodes. Action potentials, therefore, occur only at the nodes of Ranvier and seem to “leap” from node to node—a process called saltatory conduction (from the Latin saltario = leap). The leaping is, of course, just a metaphor; the action potential at one node depolarizes the membrane at the next node to threshold, so that a new action potential is produced at the next node of Ranvier.
Myelinated axons conduct the action potential faster than unmyelinated axons. This is because myelinated axons have voltage-gated channels only at the nodes of Ranvier, which are about 1 mm apart, whereas unmyelinated axons have these channels along their entire length. Because myelinated axons have more cablelike spread of depolarization (which is faster), and fewer sites at which the action potential is produced (which is slower) than unmyelinated axons, the conduction is faster in a myelinated axon. Conduction rates in the human nervous system vary from 1.0 m/sec—in thin, unmyelinated fibers that mediate slow, visceral responses-to faster than 100 m/sec (225 miles per hour)—in thick, myelinated fibers involved in quick stretch reflexes in skeletal muscles.
In summary, the speed of action potential conduction is increased by (1) increased diameter of the axon, because this reduces the resistance to the spread of charges by cable properties; and (2) myelination, because the myelin sheath results in saltatory conduction of action potentials. These methods of affecting conduction speed are generally combined in the nervous system: the thinnest axons tend to be unmyelinated and the thickest tend to be myelinated.
The autonomic nervous system (ANS) is the part of the nervous system that is responsible for homeostasis. Except for skeletal muscle, which gets its innervation from the somatomotor nervous system, innervation to all other organs is supplied by the ANS. Nerve terminals are located in smooth muscle (eg, blood vessels, the wall of the gastrointestinal tract, and urinary bladder), cardiac muscle, and glands (eg, sweat glands and salivary glands). Although survival is possible without an ANS, the ability to adapt to environmental stressors and other challenges is severely compromised. The importance of understanding the functions of the ANS is underscored by the fact that so many drugs used to treat a vast array of diseases exert their actions on elements of the ANS. Also, many neurologic diseases or disorders result directly from a loss of preganglionic sympathetic neurons (eg, multiple system atrophy and Shy–Drager syndrome) and other common diseases (eg, Parkinson disease and diabetes) are associated with autonomic dysfunction.
The ANS has two major and anatomically distinct divisions: the sympathetic and parasympathetic nervous systems. As will be described, some target organs are innervated by both divisions and others are controlled by only one. In addition, the ANS includes the enteric nervous system within the gastrointestinal tract. The classic definition of the ANS is the preganglionic and postganglionic neurons within the sympathetic and parasympathetic divisions. This would be equivalent to defining the somatomotor nervous system as the cranial and spinal motor neurons. A modern definition of the ANS takes into account the descending pathways from several forebrain and brainstem regions as well as visceral afferent pathways that set the level of activity in sympathetic and parasympathetic nerves. This is analogous to including the many descending and ascending pathways that influence the activity of somatic motor neurons as elements of the somatomotor nervous system. The sympathetic divisions responsible for showing, expressing and feeling like fight-flight-fright response. The parasympathetic divisions responsible for rest state and digestion. It is contrary to sympathetic nervous system function.
In contrast to α-motor neurons, which are located at all spinal segments, sympathetic preganglionic neurons are located in the IML of only the first thoracic to the third or fourth lumbar segments. This is why the sympathetic nervous system is sometimes called the thoracolumbar division of the ANS. The axons of the sympathetic preganglionic neurons leave the spinal cord at the level at which their cell bodies are located and exit via the ventral root along with axons of α- and γ-motor neurons. They then separate from the ventral root via the white rami communicans and project to the adjacent sympathetic paravertebral ganglion, where some of them end on the cell bodies of the postganglionic neurons. Paravertebral ganglia are located adjacent to each thoracic and upper lumbar spinal segment; in addition, there are a few ganglia adjacent to the cervical and sacral spinal segments. The ganglia are connected to each other via the axons of preganglionic neurons that travel rostrally or caudally to terminate on postganglionic neurons located at some distance. Together these ganglia and axons form the sympathetic chain bilaterally. Some preganglionic neurons pass through the paravertebral ganglion chain and end on postganglionic neurons located in prevertebral (or collateral) ganglia close to the viscera, including the celiac, superior mesenteric, and inferior mesenteric ganglia. There are also preganglionic neurons whose axons terminate directly on the effector organ, the adrenal gland. The axons of some of the postganglionic neurons leave the chain ganglia and reenter the spinal nerves via the gray rami communicans and are distributed to autonomic effectors in the areas supplied by these spinal nerves. These postganglionic sympathetic nerves terminate mainly on smooth muscle (eg, blood vessels and hair follicles) and on sweat glands in the limbs. Other postganglionic fibers leave the chain ganglia to enter the thoracic cavity to terminate in visceral organs. Postganglionic fibers from prevertebral ganglia also terminate in visceral targets.
The parasympathetic nervous system is sometimes called the craniosacral division of the ANS because of the location of its preganglionic neurons; preganglionic neurons are located in several cranial nerve nuclei (III, VII, IX, and X) and in the IML of the sacral spinal cord. The cell bodies in the Edinger–Westphal nucleus of the oculomotor nerve project to the ciliary ganglia to innervate the sphincter (constrictor) muscle of the iris and the ciliary muscle. Neurons in the superior salivatory nucleus of the facial nerve project to the sphenopalatine ganglia to innervate the lacrimal glands and nasal and palatine mucous membranes and to the submandibular ganglia to innervate the submandibular (also called submaxillary) and sublingual glands. The cell bodies in the inferior salivatory nucleus of the glossopharyngeal nerve project to the otic ganglion to innervate the parotid salivary gland. Vagal preganglionic fibers synapse on ganglia cells clustered within the walls of visceral organs; thus these parasympathetic postganglionic fibers are very short. Neurons in the nucleus ambiguus innervate the sinoatrial (SA) and atrioventricular (AV) nodes in the heart; and neurons in the dorsal motor vagal nucleus innervate the esophagus, trachea, lungs, and gastrointestinal tract. The parasympathetic sacral outflow (pelvic nerve) supplies the pelvic viscera via branches of the second to fourth sacral spinal nerves.
The parasympathetic (at left) and sympathetic (at right) divisions of the autonomic nervous system. Although single nerves are shown exiting the brainstem and spinal cord, all represent paired (left and right) nerves. Only one sympathetic trunk is indicated, although there are two, one on each side of the spinal cord. The celiac, superior mesenteric, and inferior mesenteric ganglia are collateral ganglia. Not shown are the fibers passing to the liver, blood vessels, genitalia, and skin glands.
The basic unit of integrated reflex activity is the reflex arc. This arc consists of a sense organ, an afferent neuron, one or more synapses within a central integrating station, an efferent neuron, and an effector. The afferent neurons enter via the dorsal roots or cranial nerves and have their cell bodies in the dorsal root ganglia or in the homologous ganglia of the cranial nerves. The efferent fibers leave via the ventral roots or corresponding motor cranial nerves. Activity in the reflex arc starts in a sensory receptor with a receptor potential whose magnitude is proportional to the strength of the stimulus. This generates all-or-none action potentials in the afferent nerve, the number of action potentials being proportional to the size of the receptor potential. In the central nervous system (CNS), the responses are again graded in terms of excitatory postsynaptic potentials (EPSPs) and inhibitory postsynaptic potentials (IPSPs) at the synaptic junctions. All-or-none responses (action potentials) are generated in the efferent nerve. When these reach the effector, they again set up a graded response. When the effector is smooth muscle, responses summate to produce action potentials in the smooth muscle. In contrast, when the effector is skeletal muscle, the graded response is adequate to produce action potentials that bring about muscle contraction. The connection between the afferent and efferent neurons is in the CNS, and activity in the reflex arc is modified by the multiple inputs converging on the efferent neurons or at any synaptic station within the reflex arc. The stimulus that triggers a reflex is generally very precise. This stimulus is called the adequate stimulus for the particular reflex. A dramatic example is the scratch reflex in the dog. This spinal reflex is adequately stimulated by multiple linear touch stimuli such as those produced by an insect crawling across the skin. The response is vigorous scratching of the area stimulated. If the multiple touch stimuli are widely separated or not in a line, the adequate stimulus is not produced and no scratching occurs. Fleas crawl, but they also jump from place to place. This jumping separates the touch stimuli so that an adequate stimulus for the scratch reflex is not produced.
The simplest reflex arc is one with a single synapse between the afferent and efferent neurons, and reflexes occurring in them are called monosynaptic reflexes. Reflex arcs in which interneurons are interposed between the afferent and efferent neurons are called polysynaptic reflexes. There can be anywhere from two to hundreds of synapses in a polysynaptic reflex arc. When a skeletal muscle with an intact nerve supply is stretched, it contracts. This response is called the stretch reflex or myotatic reflex. The stimulus that initiates this reflex is stretch of the muscle, and the response is contraction of the muscle being stretched. The sense organ is a small encapsulated spindlelike or fusiform-shaped structure called the muscle spindle, located within the fleshy part of the muscle. The impulses originating from the spindle are transmitted to the CNS by fast sensory fibers that pass directly to the motor neurons that supply the same muscle. The neurotransmitter at the central synapse is glutamate. The stretch reflex is the best known and studied monosynaptic reflex and is typified by the knee jerk reflex.
The contractile mechanism in skeletal muscle largely depends on the proteins myosin-II, actin, tropomyosin, and troponin. Troponin is made up of three subunits: troponin I, troponin T, and troponin C. Other important proteins in muscle are involved in maintaining the proteins that participate in contraction in appropriate structural relation to one another and to the extracellular matrix. microscope. The parts of the cross-striations are frequently identified by letters. The light I band is divided by the dark Z line, and the dark A band has the lighter H band in its center. A transverse M line is seen in the middle of the H band, and this line plus the narrow light areas on either side of it are sometimes called the pseudo-H zone. The area between two adjacent Z lines is called a sarcomere. The orderly arrangement of actin, myosin, and related proteins that produces this pattern. The thick filaments, which are about twice the diameter of the thin filaments, are made up of myosin; the thin filaments are made up of actin, tropomyosin, and troponin. The thick filaments are lined up to form the A bands, whereas the array of thin filaments extends out of the A band and into the less dense staining I bands. The lighter H bands in the center of the A bands are the regions where, when the muscle is relaxed, the thin filaments do not overlap the thick filaments. The Z lines allow for anchoring of the thin filaments. If a transverse section through the A band is examined under the electron microscope, each thick filament is seen to be surrounded by six thin filaments in a regular hexagonal pattern.
The form of myosin found in muscle is myosin-II, with two globular heads and a long tail. The heads of the myosin molecules form cross-bridges with actin. Myosin contains heavy chains and light chains, and its heads are made up of the light chains and the amino terminal portions of the heavy chains. These heads contain an actin-binding site and a catalytic site that hydrolyzes adenosine triphosphate (ATP). The myosin molecules are arranged symmetrically on either side of the center of the sarcomere, and it is this arrangement that creates the light areas in the pseudo-H zone. The M line is the site of the reversal of polarity of the myosin molecules in each of the thick filaments. At these points, there are slender cross-connections that hold the thick filaments in proper array. Each thick filament contains several hundred myosin molecules. The thin filaments are polymers made up of two chains of actin that form a long double helix. Tropomyosin molecules are long filaments located in the groove between the two chains in the actin. Each thin filament contains 300–400 actin molecules and 40–60 tropomyosin molecules. Troponin molecules are small globular units located at intervals along the tropomyosin molecules. Each of the three troponin subunits has a unique function: Troponin T binds the troponin components to tropomyosin, troponin I inhibits the interaction of myosin with actin, and troponin C contains the binding sites for the Ca2+ that helps initiate contraction.
Some additional structural proteins that are important in skeletal muscle function include actinin, titin, and desmin. Actinin binds actin to the Z lines. Titin, the largest known protein (with a molecular mass near 3,000,000 Da), connects the Z lines to the M lines and provides scaffolding for the sarcomere. It contains two kinds of folded domains that provide muscle with its elasticity. At first when the muscle is stretched there is relatively little resistance as the domains unfold, but with further stretch there is a rapid increase in resistance that protects the structure of the sarcomere. Desmin adds structure to the Z lines in part by binding the Z lines to the plasma membrane. It should be noted that although these proteins are important in muscle structure/function, by no means do they represent an exhaustive list.
The muscle fibrils are surrounded by structures made up of membranes that appear in electron micrographs as vesicles and tubules. These structures form the sarcotubular system, which is made up of a T system and a sarcoplasmic reticulum. The T system of transverse tubules, which is continuous with the sarcolemma of the muscle fiber, forms a grid perforated by the individual muscle fibrils. The space between the two layers of the T system is an extension of the extracellular space. The sarcoplasmic reticulum, which forms an irregular curtain around each of the fibrils, has enlarged terminal cisterns in close contact with the T system at the junctions between the A and I bands. At these points of contact, the arrangement of the central T system with a cistern of the sarcoplasmic reticulum on either side has led to the use of the term triads to describe the system. The T system, which is continuous with the sarcolemma, provides a path for the rapid transmission of the action potential from the cell membrane to all the fibrils in the muscle. The sarcoplasmic reticulum is an important store of Ca2+ and also participates in muscle metabolism.
The large dystrophin protein (molecular mass 427,000 Da) forms a rod that connects the thin actin filaments to the transmembrane protein β-dystroglycan in the sarcolemma by smaller proteins in the cytoplasm, syntrophins. β-dystroglycan is connected to merosin (merosin refers to laminins that contain the α2 subunit in their trimeric makeup) in the extracellular matrix by α-dystroglycan. The dystroglycans are in turn associated with a complex of four transmembrane glycoproteins: α-, β-, γ-, and δ-sarcoglycan. This dystrophin–glycoprotein complex adds strength to the muscle by providing a scaffolding for the fibrils and connecting them to the extracellular environment. Disruption of these important structural features can result in several different muscular dystrophies.
When muscle cells are viewed in the electron microscope, which can produce images at several thousand times the magnification possible in an ordinary light microscope, each cell is seen to be composed of many subunits known as myofibrils (fibrils = little fibers). These myofibrils are approximately 1 micrometer (1 μ m) in diameter and extend in parallel rows from one end of the muscle fiber to the other. The myofibrils are so densely packed that other organelles, such as mitochondria and intracellular membranes, are restricted to the narrow cytoplasmic spaces that remain between adjacent myofibrils. When a muscle fiber is seen with an electron microscope, its striations do not extend all the way across its width. Rather, the dark A bands and light I bands that produce the striations are seen within each myofibril. Because the dark and light bands of different myofibrils are stacked in register (aligned vertically) from one side of the muscle fiber to the other, and the individual myofibrils are not visible with an ordinary light microscope, the entire muscle fiber seems to be striated under a light microscope.
Each myofibril contains even smaller structures called myofilaments. When a myofibril is observed at high magnification in longitudinal section (side view), the A bands are seen to contain thick filaments. These are about 110 angstroms thick (110 Å, where 1 Å = 10 − 10 m) and are stacked in register. It is these thick filaments that give the A band its dark appearance. The lighter I band, by contrast, contains thin filaments (from 50 to 60 Å thick). The thick filaments are primarily composed of the protein myosin, and the thin filaments are primarily composed of the protein actin. The I bands within a myofibril are the lighter areas that extend from the edge of one stack of thick filaments to the edge of the next stack of thick filaments. They are light in appearance because they contain only thin filaments. The thin filaments, however, do not end at the edges of the I bands. Instead, each thin filament extends partway into the A bands on each side (between the stack of thick filaments on each side of an I band). Because thick and thin filaments overlap at the edges of each A band, the edges of the A band are darker in appearance than the central region. These central lighter regions of the A bands are called the H bands (for helle, a German word meaning “bright”). The central H bands thus contain only thick filaments that are not overlapped by thin filaments. In the center of each I band is a thin dark Z line. The arrangement of thick and thin filaments between a pair of Z lines forms a repeating pattern that serves as the basic subunit of striated muscle contraction. These subunits, from Z to Z, are known as sarcomeres. A longitudinal section of a myofibril thus presents a side view of successive sarcomeres. This side view is, in a sense, misleading; there are numerous sarcomeres within each myofibril that are out of the plane of the section (and out of the picture). A better appreciation of the three-dimensional structure of a myofibril can be obtained by viewing the myofibril in cross section. In this view, it can be seen that the Z lines are actually Z discs, and that the thin filaments that penetrate these Z discs surround the thick filaments in a hexagonal arrangement. If we concentrate on a single row of dark thick filaments in this cross section, the alternating pattern of thick and thin filaments seen in longitudinal section becomes apparent. The M lines are produced by protein filaments located at the center of the thick filaments (and thus the A band) in a sarcomere. These serve to anchor the thick filaments, helping them to stay together during a contraction. Also shown are filaments of titin, a type of elastic protein that runs through the thick filaments from the M lines to the Z discs. Because of its elastic properties, titin is believed to contribute to the elastic recoil of muscles that helps them to return to their resting length during muscle relaxation.
Sliding theory events:
1. A myofiber, together with all its myofibrils, shortens by movement of the insertion toward the origin of the muscle.
2. Shortening of the myofibrils is caused by shortening of the sarcomeres—the distance between Z lines (or discs) is reduced.
3. Shortening of the sarcomeres is accomplished by sliding of the myofilaments—the length of each filament remains the same during contraction.
4. Sliding of the filaments is produced by asynchronous power strokes of myosin cross bridges, which pull the thin filaments (actin) over the thick filaments (myosin).
5. The A bands remain the same length during contraction, but are pulled toward the origin of the muscle.
6. Adjacent A bands are pulled closer together as the I bands between them shorten.
7. The H bands shorten during contraction as the thin filaments on the sides of the sarcomeres are pulled toward the middle.
When a muscle contracts it decreases in length as a result of the shortening of its individual fibers. Shortening of the muscle fibers, in turn, is produced by shortening of their myofibrils, which occurs as a result of the shortening of the distance from Z disc to Z disc. As the sarcomeres shorten in length, however, the A bands do not shorten but instead move closer together. The I bands—which represent the distance between A bands of successive sarcomeres—decrease in length. The thin filaments composing the I band, however, do not shorten. Close examination reveals that the thick and thin filaments remain the same length during muscle contraction. Shortening of the sarcomeres is produced not by shortening of the filaments, but rather by the sliding of thin filaments over and between the thick filaments. In the process of contraction, the thin filaments on either side of each A band slide deeper and deeper toward the center, producing increasing amounts of overlap with the thick filaments. The I bands (containing only thin filaments) and H bands (containing only thick filaments) thus get shorter during contraction.
Cross Bridges
Sliding of the filaments is produced by the action of numerous cross bridges that extend out from the myosin toward the actin. These cross bridges are part of the myosin proteins that extend from the axis of the thick filaments to form “arms” that terminate in globular “heads”. A myosin protein has two globular heads that serve as cross bridges. The orientation of the myosin heads on one side of a sarcomere is opposite to that of the other side, so that, when the myosin heads form cross bridges by attaching to actin on each side of the sarcomere, they can pull the actin from each side toward the center. Isolated muscles are easily stretched (although this is opposed in the body by the stretch reflex, described in a later section), demonstrating that the myosin heads are not attached to actin when the muscle is at rest. Each globular myosin head of a cross bridge contains an ATP-binding site closely associated with an actin-binding site. The globular heads function as myosin ATPase enzymes, splitting ATP into ADP and Pi. This reaction must occur before the myosin heads can bind to actin. When ATP is hydrolyzed to ADP and Pi, the phosphate binds to the myosin head, phosphorylating it and causing it to change its conformation so that it becomes “cocked” (by analogy to the hammer of a gun). The position of the myosin head has changed and it now has the potential energy required for contraction. Perhaps a more apt analogy is with a bow and arrow: The energized myosin head is like a pulled bowstring; it is now in position to bind to actin, right) so that its stored energy can be released in the next step. Once the myosin head binds to actin, forming a cross bridge, the bound Pi is released (the myosin head becomes dephosphorylated). This results in a conformational change in the myosin, causing the cross bridge to produce a power stroke. This is the force that pulls the thin filaments toward the center of the A band. After the power stroke, with the myosin head now in its flexed position, the bound ADP is released as a new ATP molecule binds to the myosin head. This release of ADP and binding to a new ATP is required for the myosin head to break its bond with actin after the power stroke is completed. The myosin head will then split ATP to ADP and Pi, and—if nothing prevents the binding of the myosin head to the actin—a new cross-bridge cycle will occur.
Note that the splitting of ATP is required before a cross bridge can attach to actin and undergo a power stroke, and that the attachment of a new ATP is needed for the cross bridge to release from actin at the end of a power stroke. A single cross-bridge power stroke pulls the actin filament a distance of 6 nanometers (6 nm), and all of the cross bridges acting together in a single cycle will shorten the muscle by less than 1% of its resting length. Muscles can shorten up to 60% of their resting lengths, so the contraction cycles must be repeated many times. For this to occur the cross bridges must detach from the actin at the end of a power stroke, reassume their resting orientation, and then reattach to the actin and repeat the cycle. During normal contraction, however, only a portion of the cross bridges are attached at any given time. The power strokes are thus not in synchrony, as the strokes of a competitive rowing team would be. Rather, they are like the actions of a team engaged in tug-of-war, where the pulling action of the members is asynchronous. Some cross bridges are engaged in power strokes at all times during the contraction. The force produced by each power stroke is constant, but when the muscle’s load is greater, the number of cross bridges engaged in power strokes is increased to generate more force.
Regulation of Contraction
When the cross bridges attach to actin, they undergo power strokes and cause muscle contraction. In order for a muscle to relax, therefore, the attachment of myosin cross bridges to actin must be prevented. The regulation of cross-bridge attachment to actin is a function of two proteins that are associated with actin in the thin filaments. The actin filament—or F-actin —is a polymer formed of 300 to 400 globular subunits (G-actin), arranged in a double row and twisted to form a helix. A different type of protein, known as tropomyosin, lies within the groove between the double row of G-actin monomers. There are 40 to 60 tropomyosin molecules per thin filament, with each tropomyosin spanning a distance of approximately seven actin subunits.
Attached to the tropomyosin, rather than directly to the actin, is a third type of protein called troponin. Troponin is actually a complex of three proteins. These are troponin I (which inhibits the binding of the cross bridges to actin), troponin T (which binds to tropomyosin), and troponin C (which binds Ca2+). Troponin and tropomyosin work together to regulate the attachment of cross bridges to actin, and thus serve as a switch for muscle contraction and relaxation. In a relaxed muscle, the position of the tropomyosin in the thin filaments is such that it physically blocks the cross bridges from bonding to specific attachment sites in the actin. Thus, in order for the myosin cross bridges to attach to actin, the tropomyosin must be moved. This requires the interaction of troponin with Ca2+.
Twitch, Summation, and Tetanus
Contractions of isolated muscles in response to electrical shocks mimic the behavior of muscles when they contract within the body. When the muscle is stimulated with a single electric shock of sufficient voltage, it quickly contracts and relaxes. This response is called a twitch. Increasing the stimulus voltage increases the strength of the twitch, up to a maximum. The strength of a muscle contraction can thus be graded, or varied—an obvious requirement for the proper control of skeletal movements. If a second electric shock is delivered immediately after the first, it will produce a second twitch that may partially “ride piggyback” on the first. This response is called summation. Stimulation of fibers within a muscle in vitro with an electric stimulator, or in vivo by motor axons, usually results in the full contraction of the individual fibers. Stronger muscle contractions are produced by the stimulation of greater numbers of muscle fibers. Skeletal muscles can thus produce graded contractions, the strength of which depends on the number of fibers stimulated rather than on the strength of the contractions of individual muscle fibers. If the stimulator is set to deliver an increasing frequency of electric shocks automatically, the relaxation time between successive twitches will get shorter and shorter as the strength of contraction increases in amplitude. This effect is known as incomplete tetanus. Finally, at a particular “fusion frequency” of stimulation, there is no visible relaxation between successive twitches. Contraction is smooth and sustained, as it is during normal muscle contraction in vivo. This smooth, sustained contraction is called complete tetanus. The term tetanus should not be confused with the disease of the same name, which is accompanied by a painful state of muscle contracture, or tetany.
Muscle Fatigue: If a muscle repeatedly performs maximal acute or chronic submaximal work, the force of the contractions gradually decreases. It is called as muscle fatigue.
Role of Ca2+ in Muscle Contraction
Scientists long thought that Ca 2 + only served to form the calcium phosphate crystals that hardened bone, enamel, and dentin. In 1883, Sidney Ringer published the results of a surprisingly simple experiment that changed that idea. He isolated rat hearts and found that they beat well when placed in isotonic solutions made with the hard water from a London tap. When he made the isotonic solutions with distilled water, however, the hearts gradually stopped beating. This could be reversed, he found, if he added Ca2+ to the solutions. This demonstrated a role for Ca2+ in muscle contraction, a role that scientists now understand in some detail. In a relaxed muscle, when tropomyosin blocks the attachment of cross bridges to actin, the concentration of Ca2+ in the sarcoplasm (cytoplasm of muscle cells) is very low. When the muscle cell is stimulated to contract, mechanisms that will be discussed shortly cause the concentration of Ca2+ in the sarcoplasm to quickly rise. Some of this Ca2+ attaches to troponin, causing a conformational change that moves the troponin complex and its attached tropomyosin out of the way so that the cross bridges can attach to actin. Once the attachment sites on the actin are exposed, the cross bridges can bind to actin, undergo power strokes, and produce muscle contraction.
The position of the troponin-tropomyosin complexes in the thin filaments is thus adjustable. When Ca 2 + is not attached to troponin, the tropomyosin is in a position that inhibits attachment of myosin heads to actin, preventing muscle contraction. When Ca2+ attaches to troponin, the troponin-tropomyosin complexes shift position. The myosin heads can then attach to actin, produce a power stroke, and detach from actin. These contraction cycles can continue as long as Ca2+ is attached to troponin.
The striations in cardiac muscle are similar to those in skeletal muscle, and Z lines are present. Large numbers of elongated mitochondria are in close contact with the muscle fibrils. The muscle fibers branch and interdigitate, but each is a complete unit surrounded by a cell membrane. Where the end of one muscle fiber abuts on another, the membranes of both fibers parallel each other through an extensive series of folds. These areas, which always occur at Z lines, are called intercalated disks. They provide a strong union between fibers, maintaining cell-to-cell cohesion, so that the pull of one contractile cell can be transmitted along its axis to the next. Along the sides of the muscle fibers next to the disks, the cell membranes of adjacent fibers fuse for considerable distances, forming gap junctions. These junctions provide low-resistance bridges for the spread of excitation from one fiber to another. They permit cardiac muscle to function as if it were a syncytium, even though no protoplasmic bridges are present between cells. The T system in cardiac muscle is located at the Z lines rather than at the A–I junction, where it is located in mammalian skeletal muscle.
The contractile response of cardiac muscle begins just after the start of depolarization and lasts about 1.5 times as long as the action potential. The role of Ca2+ in excitation—contraction coupling is similar to its role in skeletal muscle. However, it is the influx of extracellular Ca2+ through the voltage-sensitive DHPR (Dihydropyridine receptor) in the T system that triggers calcium-induced calcium release through the RyR (Ryanodine Receptor) at the sarcoplasmic reticulum. Because there is a net influx of Ca2+ during activation, there is also a more prominent role for plasma membrane Ca2+ ATPases and the Na+/Ca2+ exchanger in recovery of intracellular Ca2+ concentrations. During phases 0 to 2 and about half of phase 3 (until the membrane potential reaches approximately –50 mV during repolarization), cardiac muscle cannot be excited again; that is, it is in its absolute refractory period. It remains relatively refractory until phase 4. Therefore, tetanus of the type seen in skeletal muscle cannot occur. Of course, tetanization of cardiac muscle for any length of time would have lethal consequences, and in this sense, the fact that cardiac muscle cannot be tetanized is a safety feature [Ryanodine drug from Ryania speisosa which act as insecticide].
Smooth muscle is distinguished anatomically from skeletal and cardiac muscle because it lacks visible cross-striations. Actin and myosin-II are present, and they slide on each other to produce contraction. However, they are not arranged in regular arrays, as in skeletal and cardiac muscle, and so the striations are absent. Instead of Z lines, there are dense bodies in the cytoplasm and attached to the cell membrane, and these are bound by α-actinin to actin filaments. Smooth muscle also contains tropomyosin, but troponin appears to be absent. The isoforms of actin and myosin differ from those in skeletal muscle. A sarcoplasmic reticulum is present, but it is less extensive than those observed in skeletal or cardiac muscle. In general, smooth muscles contain few mitochondria and depend, to a large extent, on glycolysis for their metabolic needs.
There is considerable variation in the structure and function of smooth muscle in different parts of the body. In general, smooth muscle can be divided into unitary (or visceral) smooth muscle and multiunit smooth muscle. Unitary smooth muscle occurs in large sheets, has many low-resistance gap junctional connections between individual muscle cells, and functions in a syncytial fashion. Unitary smooth muscle is found primarily in the walls of hollow viscera. The musculature of the intestine, the uterus, and the ureters are examples. Multiunit smooth muscle is made up of individual units with few (or no) gap junctional bridges. It is found in structures such as the iris of the eye, in which fine, graded contractions occur. It is not under voluntary control, but it has many functional similarities to skeletal muscle. Each multiunit smooth muscle cell has en passant endings of nerve fibers, but in unitary smooth muscle there are en passant junctions on fewer cells, with excitation spreading to other cells by gap junctions. In addition, these cells respond to hormones and other circulating substances. Blood vessels have both unitary and multiunit smooth muscle in their walls.
As in skeletal and cardiac muscle, Ca2+ plays a prominent role in the initiation of contraction of smooth muscle. However, the source of Ca2+ increase can be quite different in unitary smooth muscle. Depending on the activating stimulus, Ca2+ increase can be due to influx through voltage- or ligand-gated plasma membrane channels, efflux from intracellular stores through the RyR, efflux from intracellular stores through the inositol trisphosphate receptor (IP3R) Ca2+ channel, or via a combination of these channels. In addition, the lack of troponin in smooth muscle prevents Ca2+ activation via troponin binding. Rather, myosin in smooth muscle must be phosphorylated for activation of the myosin ATPase. Phosphorylation and dephosphorylation of myosin also occur in skeletal muscle, but phosphorylation is not necessary for activation of the ATPase. In smooth muscle, Ca2+ binds to calmodulin, and the resulting complex activates calmodulin-dependent myosin light chain kinase. This enzyme catalyzes the phosphorylation of the myosin light chain on serine at position 19, increasing its ATPase activity.
Myosin is dephosphorylated by myosin light chain phosphatase in the cell. However, dephosphorylation of myosin light chain kinase does not necessarily lead to relaxation of the smooth muscle. Various mechanisms are involved. One appears to be a latch bridge mechanism by which myosin cross-bridges remain attached to actin for some time after the cytoplasmic Ca2+ concentration falls. This produces sustained contraction with little expenditure of energy, which is especially important in vascular smooth muscle. Relaxation of the muscle presumably occurs when the Ca2+-calmodulin complex finally dissociates or when some other mechanism comes into play. The events in multiunit smooth muscle are generally similar. Unitary smooth muscle is unique in that, unlike other types of muscle, it contracts when stretched in the absence of any extrinsic innervation. Stretch is followed by a decline in membrane potential, an increase in the frequency of spikes, and a general increase in tone. If epinephrine or norepinephrine is added to a preparation of intestinal smooth muscle arranged for recording of intracellular potentials in vitro, the membrane potential usually becomes larger, the spikes decrease in frequency, and the muscle relaxes. Acetylcholine has an effect opposite to that of norepinephrine on the membrane potential and contractile activity of intestinal smooth muscle.
Muscular contraction involves shortening of the contractile elements, but because muscles have elastic and viscous elements in series with the contractile mechanism, it is possible for contraction to occur without an appreciable decrease in the length of the whole muscle. Such a contraction is called isometric (“same measure” or length). Contraction against a constant load with a decrease in muscle length is isotonic (“same tension”). Note that because work is the product of force times distance, isotonic contractions do work, whereas isometric contractions do not. In other situations, muscle can do negative work while lengthening against a constant weight.
Skeletal Muscle
Cardiac Muscle
Smooth Muscle
Striated; actin and myosin arranged in sarcomeres
Striated; actin and myosin arranged in sarcomeres
Not striated; more actin than myosin; actin inserts into dense bodies and cell membrane
Well-developed sarcoplasmic reticulum and transverse tubules
Moderately developed sarcoplasmic reticulum and transverse tubules
Poorly developed sarcoplasmic reticulum; no transverse tubules
Contains troponin in the thin filaments
Contains troponin in the thin filaments
Contains calmodulin, a protein that, when bound to Ca2+, activates the enzyme myosin light-chain kinase
Ca2+ released into cytoplasm from sarcoplasmic reticulum
Ca2+ enters cytoplasm from sarcoplasmic reticulum and extracellular fluid
Ca2+ enters cytoplasm from extracellular fluid, sarcoplasmic reticulum, and perhaps mitochondria
Cannot contract without nerve stimulation; denervation results in muscle atrophy
Can contract without nerve stimulation; action potentials originate in pacemaker cells of heart
Maintains tone in absence of nerve stimulation; visceral smooth muscle produces pacemaker potentials; denervation results in hypersensitivity to stimulation
Muscle fibers stimulated independently; no gap junctions
Gap junctions present as intercalated discs
Gap junctions generally present
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| 0.83643 |
Saccharomyces cerevisiae
0 known processes
tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein, theta polypeptide b
(Aliases: ywhaz,wu:fb36f06,wu:fa91b01,wu:fk86h02,wu:fb02e12,zgc:55499,ywhaq1)
ywhaqb biological process predictions
Filter by process size:
Biological processGO term IDProcess sizeProbabilityFunc Analog Org
ywhaqb disease predictions
DiseaseDO term IDSizeProbabilityFunc Analog Org
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| 0.962421 |
$ 229.99
Qty available: 0
Constructed of strong waterproof and breathable 1200D polyester outer with a shine enhancing polyester lining and fiberfill inside for warmth. Patented V-Front closure wraps around the point of the shoulder keeping the blnaket light across the chest and relieving pressure on the shoulders. Deep V allows the horse to move more freely. Clips are strong and non-swivel for extra security, with a hook and loop fastening behind them to alleviate gapes.
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About Seesaw Sign Up
Teachers, save “Solid Shapes” to assign it to your class.
Angela Ham
Student Instructions
Solid Shapes
1. Find a solid shape in the classroom 2. Take a picture of your shape 3. How many flat surfaces? 4. How many vertices? 5. The name of your solid shape
3rd Grade, 2nd Grade, 4th Grade, Math
116 teachers like this
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Tabla Drumming
Workshop Information
Explore rhythm and counting and learn some fiery finger-work with our expert tabla tutors. Why not use a tabla drumming workshop to explore the science behind sound?
“The work they did with the children was amazing and they all gained a great deal from it. The energy and enthusiasm shown by the artists was clear to all and the teaching staff felt inspired by their work.”
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| 0.810821 |
User FAQs
If you have a question, please send it to us.
1) What do SOAP and REST stand for ?
SOAP = Simple Object Access Protocol
REST = REpresentational State Transfer
2) What are the differences between SOAP and REST ?
SOAP - describes itself using a wsdl (web description language) and has a defined contract
REST - lightweight http protocol that can return different formats (text, html, xml)
3) How can you return an error from a SOAP Web Service ?
Make sure the exception raised is derived from the SOAPException class.
4) Write a function that takes a date and returns the quarter that the date is in ?
public static int GetQuarter(System.DateTime myDateTime)
return System.Convert.ToInt32(System.Math.Ceiling(myDateTime.Month(3D));
The "D" literal number suffix tells the compiler that the literal value passed to the Month method is of data type double.
You can use this when you want an integer number to be treated as a double.
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Happy Codings - Programming Code Examples
C Programming Code Examples
C > Code Snippets Code Examples
Demonstrate multiple loop control variables
Program Implement the Vizing's Theorem - The chromatic index of the simple graph can be either 'maxDegree' or maxDegree+1. The chromatic index is the maximum number of color needed for the 'edge coloring' of graph.
C Program Code Concatenates two Strings - You can 'concatenate two strings' easily using standard library function strcat() but, in this C program 'concatenates two strings' manually without using 'strcat()' function. Calculate the
C++ Code Solves Tower of Hanoi Problem - In The C++ program, displays the solution to the Tower of Hanoi problem using the base-2 representation of the move number with the following rules:- There is one binary digit (bit)
C Output of a Program is Input of Another - Pipe the output of program to the input of another. Duplicate stdin and stdout so we can restore them later. Make the write end of the pipe stdout. Run the program. Its output will
C Language Code Display Prime Numbers - Any whole number which is Greater than 1 & has only two factors that is 1 and the number itself, is called a "Prime Number". Other than these two number it has No Positive Divisor.
C++ Program Displays Factors of Number - Find all 'factors' of an integer using for loop & if statement. Takes a positive integer from an user & displays all the factors of that number. In this program, an integer entered by user is
Generate a Sequence of N Characters for a - This algorithm takes the input of the 'specific' sequence. It generates random Subsequence from the given character string. A function to generate 'random' sequence of a given length
Compile Ttime Polymorphism in The C++ - In this C++ example, we have two functions with "same name" but different number of arguments. Based on how many parameters we pass during Function call "Determines"
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If you look at a radial probability chart for a given electron sublevel (excluding n=1), there is a probability of an electron in that sublevel being closer to the nucleus. The electron should lose energy if it is closer to the nucleus because it experiences a greater force of attraction to the nucleus, but how is this possible if all electrons in a given sublevel have the same energy?
• 2
$\begingroup$ Stop thinking of probability as probability. An electron is not here or there; it is everywhere at once. $\endgroup$ Oct 10 '17 at 16:13
• $\begingroup$ No, it doesn't. If you believe in electron orbits imagine it to be elliptical like in B-S model. $\endgroup$
– Mithoron
Oct 10 '17 at 17:07
You are trying to apply macroscopic understanding to the world of quantum mechanics. This thinking is doomed to fail. The energy of an electron occupying a specific orbital is that orbital’s energy. Full stop. Unless it changes its orbital it does not change energy.
• 1
$\begingroup$ The electron does not occupy the orbital, it IS the orbital! $\endgroup$
– Feodoran
Oct 11 '17 at 7:24
Your Answer
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Logical Reasoning Questions And Answers Pdf In Telugu
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Basic General Knowledge Questions and Answers. These are very important and latest Basic General Knowledge Questions for all competitive examinations. You can answer the GK Questions for fun too. Candidates can enhance your public speaking skills with this General knowledge.
Logical Reasoning Questions and Answers
Learn more. The logical reasoning, also known as critical thinking or analytic reasoning, involves one's ability to isolate and identify the various components of any given argument. A person with a higher logical reasoning ability is better equipped to work in positions that require quick decision making. So, it is not a surprise that the logical reasoning questions commonly appear in any placement tests, competitive exams or entrance exams. To help the students preparing for competitive exams and placement tests, we provide interactive online practice logical reasoning tests with asnwers in multiple choice objective type. Each of the below online tests consists of ten multiple choice objective type questions with answers.
This is an alternating series in alphabetical order. The first and third letters are alphabetical beginning with J. The third letter is repeated as a first letter in each subsequent three-letter segment. The second and forth letters in the series, L and A, are static. The first and third letters consist of an alphabetical order beginning with the letter E. Because the letters are the same, concentrate on the number series, which is a simple 2, 3, 4, 5, 6 series, and follows each letter in order.
Quantitative Chemistry Questions And Answers Pdf
Reasoning Section is most important sections in all recruitment exam. Some time Reasoning questions are very confusing and time consuming and candidates face problem in this section as they find it difficult to finish it on time. In this page we will provide you few reasoning PDF to download with answer. Before downloading reasoning questions PDF we must know about the reasoning. If we are asked to express it verbally, we may do so as follows.
The logical reasoning section is an important part of competitive exams. It contains different types of reasoning questions which are intended to judge analytical and logical reasoning skills of the candidate. The logical reasoning questions can be verbal or non-verbal: In verbal logical reasoning questions , the concepts and problems are expressed in words. The candidates are required to read and understand the given text or paragraph and according choose the right answer from the given options. In non-verbal logical reasoning questions, the concepts and problems are expressed in the form of figures, images or diagrams and the candidates are required to understand them before choosing the right answer out of the given options.
Therefore, this situation is making many participants, to check for the various online sources to practice and gain knowledge on reasoning subject. To make this procedure easier, here we have provided the Reasoning questions and answers with solutions. Practice all the reasoning chapters provided here and we are sure you can easily crack any online exam with ease. Along with the solutions, all the people can also find the proper explanation on this page itself. This will help many aspirants for sure. Mostly, those people who had applied for the interview, Entrance Examinations, Competitive Exams can get the help of Reasoning Quiz with Solutions. Now, you can even practice them all, as even check your answers.
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Topics prescribed by Various Health Science. Science studies the physical world. Quantitative Aptitude PDF Notes - Quantitative Aptitude is an important section in the employment-related The Quantitative Aptitude section has questions related to Profit and Loss, Percentage and Discount, Simple Read the questions carefully so that you understand it properly before answering. This empowers people to learn from each other and to better understand the world.
Verbal Reasoning - Mental ability is one of the common topics found in most of the entrance exams. Mental ability tests our level at which we learn things, understands instructions and solve problems. Verbal Reasoning - Mental Ability Questions encloses wide range of topics: verbal reasoning vocabulary and missing letters , Arithmetic reasoning, Blood relations, Analogy, classifications, coding and decoding, Data sufficiency, Missing characters, logical sequences, series, numbers, spontaneous reaction tests, verification of truth statements, Venn diagrams, mathematical operations, direction sense test, statements and arguments, assumption tests and more.
Ровно год назад он разбил здесь себе голову. Сегодня годовщина. Беккер кивнул, плохо соображая, какая тут связь. - Такая прическа была у Табу в день гибели.
Говорит коммандер Тревор Стратмор. У нас в шифровалке человек взят в заложники. Быстро пришлите сюда людей.
Преступники, террористы и шпионы, которым надоело прослушивание их телефонов, с радостью встретили это новое средство глобальной коммуникации. Электронная почта соединила безопасность обычной почты со скоростью телефонной связи. С тех пор как сообщения стали передаваться по подземным волоконно-оптическим линиям, а не с помощью радиоволн, они оказались полностью защищенными от перехвата - таков по крайней мере был замысел. В действительности перехват электронных писем, передвигаемых по Интернету, был детской забавой для технических гуру из АНБ. Интернет не был создан, как считали многие, в эру домашних персональных компьютеров.
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Hold my hand ebook pdf free download psychoanalytic terms and concepts pdf
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Date Published 2017, November 16
Authors Climate Analytics
The use of blue carbon to offset and hence effectively avoid required emission reductions in other sectors such as fossil fuel combustion, industry, agriculture, international aviation and marine activities would undermine our ability to limit temperature rise to 1.5°C.
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Type 2 diabetes (T2D) results from interaction between genetic variation and environmental exposures that influence insulin secretion in pancreatic islets and insulin resistance in skeletal muscle and other peripheral tissues. Genome-wide association studies (GWAS) have identified hundreds of loci that modulate risk for T2D and related insulin traits. These loci mostly occur in non protein-coding regions which makes identification of causal regulatory single nucleotide polymorphisms (SNPs) and their associated mechanisms difficult. Previous studies show that many active enhancers are transcribed into enhancer RNA (eRNA). To identify actively transcribed regulatory elements with high genomic resolution and prioritize SNPs, we generated eRNA profiles using cap analysis of gene expression (CAGE) across 57 islet and 146 skeletal muscle samples and 15 replicates of the human beta cell line EndoC-BH1. We computationally integrated these CAGE profiles with ChIP-seq profiles for five histone marks along with open chromatin ATAC-seq profiles to generate high-resolution cross-tissue chromatin states. We identify multiple CAGE-enriched chromatin states that correspond to actively transcribed promoter or enhancer regions, which are supported by diverse patterns of chromatin activity across an orthogonal set of 127 human epigenome maps. We find 11,856 CAGE+ promoter regions across islets and muscle and 54% are shared across the two tissues, whereas we observe 1,712 CAGE+ eRNA regions and only 7% are shared, indicating the cell-identity nature of these eRNA states. We find significant enrichment for GWAS and eQTL SNPs to overlap these CAGE+ chromatin states. Finally, at a subset of loci, we validate these findings using a modified high-throughput STARR-seq assay where we observe allelic activity. These results provide the highest-resolution epigenome maps for islets and muscle to date, and we are using them to fine-map GWAS SNPs.
S. Parker: None. A. Varshney: None.
American Diabetes Association/Pathway to Stop Diabetes (1-14-INI-07 to S.P.); National Institutes of Health (1R01DK117960)
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Skip to main content
How often should a water pump cycle?
1/2 HP pumps should have at least a 1 minute run time. It was stated that it was 300 cycles per day. Since there are 1440 minutes in a day, that would be a cycle every 4.8 minutes max. It doesn't take long if the pump only pumps 8 gallons.
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Cellular quality-control system identified as a culprit in coronavirus infection
Cellular quality-control system identified as a culprit in coronavirus infection
Color-enhanced scanning electron micrograph of mammalian cells infected with Middle East Respiratory Syndrome coronavirus. Credit: National Institute of Allergy and Infectious Diseases, NIH
The team, from the Department of Energy's Pacific Northwest National Laboratory and the University of North Carolina at Chapel Hill, studied the virus that causes Middle East Respiratory Syndrome (MERS), which is caused by a . MERS is much less common but much more lethal than COVID-19.
The team set out to learn more about how the virus that causes MERS damages the lungs and harms patients. In , the team analyzed tens of thousands of measurements of proteins, molecular messengers and other signals that occur after infection. They pinpointed a molecular process, part of the body's quality-control machinery, that plays a central role in causing damage from a coronavirus infection.
The broad fight against respiratory diseases
Battelle, which operates PNNL, and UNC have filed for a patent on the use of a PERK inhibitor to treat coronavirus infections. But the scientists emphasize that it's far too soon to know whether the compound could help patients. It's not currently used as a drug.
"Studies like this help us learn more about how deadly respiratory viruses operate—how they do what they do, why they attack certain parts of the lung and not others," said PNNL virologist Amy Sims, one of two first coauthors of the paper, along with PNNL scientist Hugh Mitchell.
"Studying how these viruses work helps us understand why patients exhibit the symptoms they do and ultimately how to treat or prevent disease," Sims added.
"Consider how fast a vaccine to protect against COVID-19 was created and how quickly new drugs were found to treat the disease," said Sims. "The success wasn't because scientists started from scratch when the virus appeared. They were able to build upon years and years of research understanding how the works and how it responds to coronaviruses. You never know when a certain bit of knowledge will prove crucial in the future."
Cellular quality-control system identified as a culprit in coronavirus infection
A veterinarian in Yemen takes a blood sample from a camel, part of a program to help detect diseases like MERS locally and prevent their spread. Credit: Awadh Mohammed Ba Saleh and CDC Public Health Image Library
Emergency response—for damaged proteins
The team's studies led to proteins, molecules that are the workhorses of the body's cells. Proteins carry out myriad functions to keep organisms, like people, alive and well. The body keeps close tabs, making sure that its proteins are intact and functioning.
When the body begins producing proteins that aren't up to standard for whatever reason, including infection, -repair machinery in a cell's endoplasmic reticulum goes into emergency response mode. The organelle can function like a triage center for damaged proteins in times of stress. When it's swamped with misfolded proteins, the unfolded protein response, or UPR, kicks in. The UPR puts a temporary stop to all cellular activity related to making new proteins. This buys time for the cell to make the necessary repairs to misfolded proteins.
For the current study, the handling of lung tissue and mice was done at UNC, in a laboratory headed by one of the world's top coronavirus researchers, Ralph Baric. Scientists at PNNL measured and interpreted vast amounts of data about molecular messages. Sims worked in the Baric lab while at UNC and joined PNNL early last year; the two institutions have worked together for years.
"Coronavirus infections cause complex disease phenotypes, and new strategies are needed to disentangle which host pathways are contributing to the development of severe, life-threatening outcomes," said Baric.
In addition to Sims and Mitchell, authors from PNNL include Katrina Waters, a senior author of the paper, and Jennifer Kyle, Kristin Burnum-Johnson, Richard D. Smith and Thomas Metz. From UNC, authors include Lisa Gralinski, Mariam Lam, M. Leslie Fulcher, Ande West and Scott Randell, along with senior authors Ralph Baric and Timothy Sheahan.
Explore further
More information: Amy C. Sims et al, Unfolded Protein Response Inhibition Reduces Middle East Respiratory Syndrome Coronavirus-Induced Acute Lung Injury, mBio (2021). DOI: 10.1128/mBio.01572-21
Journal information: mBio
Citation: Cellular quality-control system identified as a culprit in coronavirus infection (2021, November 1) retrieved 26 January 2022 from https://medicalxpress.com/news/2021-11-cellular-quality-control-culprit-coronavirus-infection.html
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Pregnancy Conception Calculator
The Pregnancy Conception Calculator estimates the date of conception based on the expected due date of the pregnancy, last period date, or ultrasound date. The date of conception is the day on which a person’s baby is conceived. The calculator also estimates a possible range of days during which sexual intercourse might have led to conception based on sperm being viable for 3-5 days within a woman’s body.
RelatedConception Calculator | Pregnancy Calculator | Due Date Calculator
When Did I Conceive?
When exactly did I get pregnant? Many women often ask this question when trying to figure out the exact day their pregnancy began. Often, gestational age, or the age of the baby, is calculated from the first day of the mother’s last menstrual period. However, in reality, the baby was not conceived until ovulation and the fertilization of the egg, which usually happens at least 10 days after the first day of the mother’s menstrual period.
Because there are many factors surrounding conception, it is difficult to pinpoint an exact date of conception. This calculator helps to estimate the date range of real conception and a possible range of days during which sexual intercourse might have led to conception. There are a few methods can be used to estimate the conception dates:
Last Menstrual Period
Conception usually occurs around 11-21 days after the first day of the last period of a woman who has a regular period. The estimation of conception date is based on this, but is rarely ever exact since it is difficult to know exactly when ovulation occurs. Estimating conception date can also be more difficult for women who have irregular periods, or for those who don’t remember the first day of their last period. In cases like these, one of the more accurate ways to estimate gestational age is through the use of an ultrasound.
Due Date
An estimated due date, usually based on a sonogram, is typically obtained from a healthcare provider during a prenatal visit. Based on this due date, a range of possible conception dates can be calculated.
An ultrasound, on a basic level, uses sound waves to create images of internal body structures. An ultrasound used in the context of examining the progress of the fetus in pregnant women is referred to as an “obstetric ultrasound.” This is done in real time and is a fairly standard procedure that is part of prenatal care in many countries, as it can provide information about the health of the mother and embryo/fetus, as well as the overall progress and timing of the pregnancy. Ultrasounds can be used to measure a fetus as early as five or six weeks following the mother’s last menstrual period. It is a more accurate measure in early pregnancy than it is in later stages. Ultrasound can be used in conjunction with estimates based on last menstrual period to determine a more accurate gestational age.
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| 0.775797 |
Salt Lake City, UT—A live Face-to-Face event was derailed last Sunday due to an audience member asking an unscripted question.
Alex Garcia, a member from Pocatello, Idaho, was supposed to ask: “How do you #HearHim in today’s fast paced world?” or something boring like that. Instead, in a moment of spontaneous free thinking, Garcia asked: “Was the priesthood ban on blacks a revelation or not?”
Bewildered, Presidents Oaks and Ballard began quickly thumbing though papers and note cards hoping to find a prewritten answer somewhere. The two senior church leaders quickly realized that the question was not a planned one, however. After several uneasy moments of silence and confusion President Oaks found a red notecard labeled “Difficult Questions”. He quickly began reading: “I could answer that question for you, but it is more important that you find the answer for yourself.”
Reportedly, the church has cancelled all future Face-to-Face events out of a concern that such an unexpected moment could happen again. Alex Garcia is currently awaiting his disciplinary council… excuse me, membership council.
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| 0.905596 |
Nerve Pain in Our Feet
Nerve pain can be pretty tricky to describe. Numbness, tingling and burning can all occur when a nerve or nerves are being compressed, rubbed or irritated in some way. This is especially common in our toes and the balls of our feet. The most common nerve condition in the feet is called a Morton’s Neuroma.
The nerves of our feet run between the long bones (metatarsals) that make up the balls of our feet. These nerves are especially susceptible to irritation as tight footwear or poor mechanics can easily cause the bones to shift and compress the nerves. When a nerve has been repetitively compressed or pinched it causes pain and swelling of the nerve itself. This swelling can become permanent if no changes are made, and the nerve becomes more prone to further irritation with its increased size.
Early treatment is essential and involves reducing the swelling and pain with ice and pain medication. Further treatment involves addressing problematic footwear (narrow shoes) and poor foot mechanics during walking (hyper-mobile feet).
If you are concerned about numbness or burning through the balls of your feet call our clinic at (07) 3823 5423 to see one of our Podiatrists.
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| 0.722266 |
Skip to main content
Dry Eye Blog
Dry Eye African American Man 1280×480
Blinking Exercises for Dry Eye
Blinking plays a crucial role in maintaining the right amount of moisture on the eye’s surface. If you don’t blink properly or enough, it can leave your eyes feeling dry and irritated. Fortunately, there are certain blinking exercises you can perform to prevent your eyes from becoming dry.
7 Ways to Wish Dry Eye ‘Goodbye’
What Happens If You Don’t Treat Dry Eye Syndrome?
What’s a Chalazion?
Can People With Dry Eye Syndrome Wear Eye Makeup?
Why is My Dry Eye More Severe in the Mornings?
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| 0.989535 |
Undergraduate Catalog 2020-2021
PSY 103 Stress Management(RNL)
(Also SKO 103). 3 hours; 3 credits. A comprehensive presentation of the physical, social, and psychological understanding of the human stress response. Opportunities for students to learn concrete scientific insights, practical stress management skills, and beneficial relaxation techniques are offered. Prerequisite: Passing the CUNY Assessment Test in Reading and Writing.
Cross Listed Courses
SKO 103
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| 0.99714 |
(Article/content is below...)
Rhyme Generator
Words that rhyme with vandergriff
Hm...I can't find anything...
Words that partially rhyme with vandergriff
3 syllable words that partially rhyme with vandergriff
handkerchief iosif vandagriff
2 syllable words that partially rhyme with vandergriff
1 syllable words that partially rhyme with vandergriff
Here are a few rhyme generator examples:
mccoin, inacomp, lauper, funicello, armchairs, cars, lormand, carretta, empirical, hing, rendall, bendorf, rookies, weininger, concubinage, clarion, bagsby, bury, illusionary, advisement, dog.
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| 0.880969 |
How to determine the area over a certain slope within a number of grid cells?
10-26-2021 08:06 PM
Labels (2)
New Contributor III
I've generated a FISHNET grid over my study area, and intersected it with the boundary I've sectione.... I've also generated a slope map, and now I want to determine how much area over a certain slope is within each grid cell.
Should I first select all the area within my boundary over the desired slope limit, make that a polygon feature? If so how?
Once I have that polygon feature bounding my steep slope areas I can correct map area to surface area with ADD SURFACE INFORMATION from 3D ANALYST, something I've done before. Then how do I generate a table that tells me how much of those areas falls within each grid cell?
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| 0.85094 |
Event Date and Time
Speaker: Jason C. Chow, Ph.D.
Title: Understanding contextual factors that contribute to the comorbidity of language and behavior disorders
Abstract: Although there is a substantial body of research suggesting that language and behavior are related, we know less about contextual factors that may influence their association. Some of the contributors to the strength of the relation between language and behavior or prevalence of the overlap between language and behavior disorders that I have been exploring are teacher-level factors (characteristics of teacher's talk, classroom management) and measurement (how we measure constructs of interest). We will talk about a recent line of work aimed at better understanding how peer friendships (classroom networks) are associated with language and behavioral development and discuss what are some ways we can continue to advance our understanding of language and behavior to develop practices and interventions to support children early and effectively.
HESP Seminar - Jason C. Chow, Ph.D.
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| 0.99977 |
Author -
Publisher - Puffin
Edition - 2007
Binding - Paperback
Language - English
Pages - 192
Condition - Used (Good Condition)
Bruce Chatwin carved out a literary career as unique as any writer's in this century: his books included In Patagonia, a fabulist travel narrative, The Viceroy of Ouidah, a mock-historical tale of a Brazilian slave-trader in 19th century Africa, and The Songlines, his beautiful, elegiac account of following the invisible pathways traced by the Australian aborigines.
The songlines are the invisible pathways that criss-cross Australia, ancient tracks connecting communities and following ancient boundaries. Along these lines Aboriginals passed the songs which revealed the creation of the land and the secrets of its past. In this magical account, Chatwin recalls his travels across the length and breadth of Australia seeking to find the truth about the songs and unravel the mysteries of their stories.
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| 0.999924 |
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