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Example sentences for: steady--no
How can you use “steady--no” in a sentence? Here are some example sentences to help you improve your vocabulary:
• The pictures must be in focus and steady--no bounces, no jiggles.
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Question: What is meant by 4 ply yarn?
4-ply yarn has four smaller strands twisted together to create the yarn. It is often a medium or double knitting (DK) weight yarn, but it can vary from laceweight to super bulky based on the fibers is it is made of.
Is 4 ply the same as DK?
How do I know if my yarn is 4 ply?
When you see a yarn that claims to be 4 ply, this just means that there were 4 strands of yarn spun together to make the yarn. Typically, 4 ply yarn is equivalent to medium weight yarn, which means that it is possible for double knit yarn to be 4 ply as well.
What is 4 ply yarn in the US?
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What does four-ply mean?
adjective. having a thickness made up of four layers or strands. “four-ply yarns” Synonyms: thick. not thin; of a specific thickness or of relatively great extent from one surface to the opposite usually in the smallest of the three solid dimensions.
What weight yarn is 4 ply?
Different weights of yarn generally fall into the following ranges of WPI: Lace weight 35+ Fingering weight (traditionally 4ply) 19-22. Sport weight 15-18.
What size is 4 ply yarn?
How do I know what ply my yarn is?
1. Lace or 2 ply: 35 or more.
3. Fingering or 4 ply: 19 – 22.
4. Sport: 15 – 18.
5. DK: 12 – 17.
6. Worsted or Aran: 9 – 11.
7. Bulky or Chunky: 8 – 10.
What is 3 ply yarn used for?
What is single ply yarn good for?
Single ply yarn adds a distinct aesthetic to knit and crocheted items crafted from it. You might notice a softer overall feel with less distinct stitch definition. Most single ply yarn will have a halo around it. (The “halo” is a soft fuzz surrounding the yarn strand.)
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What is the difference between 4 ply and 8 ply yarn?
What is 8 ply yarn in us?
The number of wraps will act as a gauge to assess the thickness of unmarked yarn; for example 12 wraps per inch is 12 WPI, and is used to calculate how much yarn is required for various articles, so that 12 is equivalent to 8 ply (worsted weight, medium weight) yarn.
What ply is worsted weight yarn 4?
I often use 8ply yarn when a pattern calls for yarn category 4 or worsted weight yarn and adjust my tension/stitches based on the gauge swatch.
What does ply mean?
1a : to use or wield diligently busily plying his pen. b : to practice or perform diligently ply a trade. 2 : to keep furnishing or supplying something to plied us with liquor. 3a : to make a practice of rowing or sailing over or on the boat plies the river.
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21 Ways to Encourage Learners Not to Talk During Quiet Time
Are you looking for ways to encourage students not to talk during quiet time? If so, keep reading.
1. Make the appropriate adjustments in their surroundings to prevent the student from experiencing stress, frustration, and anger.
2. Talk regularly with the student to lessen the need for them to talk to other students.
3. Provide visibility to and from the student to keep their attention when oral questions/instructions are being delivered. The teacher and the student should be able to see each other at all times. Make eye contact possible at all times.
4. Assess the appropriateness of the social situation concerning the student’s capacity and ability to function successfully.
5. Attempt several groupings to ascertain the situation in which the student is most comfortable.
6. Praise the student for raising their hand to be recognized.
7. Ask the student a question when they are most likely to be able to respond correctly (e.g., when discussing something in which the student is interested, when the teacher is sure they know the answer, etc.).
8. Teach the student to recognize when to speak, to know how much to say, and to make appropriate remarks (e.g., brief remarks, remarks within the context of the situation, remarks that are a follow-up to what has just been said, etc.).
9. Get the student to work in small groups in which they would have frequent chances to speak. As the student learns to wait longer for their turn to speak, slowly increase the size of the group.
10. Make sure that the student’s feelings are considered when it is appropriate to deal with their talking to other students (i.e., handle remarks in such a way as to not diminish the student’s enthusiasm for participation).
11. Urge the student to model the behavior of peers who are successful at not talking to others during quiet activity periods.
12. Assist the student in improving concentration skills (e.g., listening to the speaker, taking notes, preparing remarks in advance, making remarks in an appropriate context, etc.).
13. Get the student to question any directions, explanations, or instructions they do not understand prior to asking other students for information.
14. Provide directions, explanations, and instructions in a clear, concise manner to lessen the student’s need to ask other students for information.
15. Provide a predetermined signal (e.g., hand signal, oral signal, etc.) if the student talks to others during quiet activity periods.
16. After telling the student why they should not be talking, explain the reason.
17. Do not provide too much free time for the student.
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• Tumbled Bundle (A)
Tumbled Bundle (A)
citrine: attracts wealth and success | imparts joy and enthusiasm | promotes motivation | activates creativity and encourages self expression
fluorite: encourages positivity | increases confidence + concentration | promotes freedom of choice | stabilizes aura | helps in facilitating life changes
amethyst: activates spiritual awareness and intuition | enhances memory | can assist in overcoming addictions | powerful amulet for travel - protects against thieves, sickness, danger | relieves insomnia
green goldstone: a stone of wisdom + science | encourage us to reach for the stars | a powerful energy generator | protects empathic sensitivities | reminds us of the light within darkness
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Meaning of DOUGHNUTTING in English
noun Also written donutting (Lifestyle and Leisure) (Politics) In television jargon, the clustering of politicians round a speaker during a televised parliamentary debate so as to fill the shot and make the speaker appear well supported. Etymology: Formed by adding the suffix -ing to doughnut--presumably alluding to the ring shape of some doughnuts as resembling the ring of supporters, or to the jam in the middle as representing the speaker, surrounded by the apparently substantial dough of his support. History and Usage: The word is often said to have been used in connection with the first televised debates from the federal parliament in Ottawa, but Canadian newspaper reports of the time do not bear this out (describing the practice, but not using the word). When the British parliament began to be televised, and particularly when House of Commons debates first appeared on TV screens in 1989, the word enjoyed a brief vogue in the press amid speculation that members would attempt to fill the seats immediately behind the speaker so as to make the chamber appear full, even when in fact a debate had attracted only a handful of MPs. Its use in popular sources promises to be shortlived. Mr Kirkwood did have a little ring of fellow-Liberals around him. But this practice of 'doughnutting', as Canadian parliamentarians call it, exhausts the nutters more than it fools the viewers. Daily Telegraph 24 Nov. 1989, p. 14
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France's Sainte-Baume, a lush oasis in the heart of Provence
Close to the Mediterranean Sea in southern France and not far from the Alps, the regional natural park of Sainte-Baume benefits from a unique ecosystem. Since time immemorial, humans have lived in this area. They have long enjoyed its natural riches, from its forest to its water. FRANCE 24 takes you to discover this natural oasis in the heart of the Provence region.
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Temple in Tibet. Tibetan Buddhism
Tibetan religion
Secrets keep not only the catacombs, caves and pyramids, but also entire nations
And one of these secrets is the oldest religion of the Tibetans, which existed long before the appearance of the Bon religion. And since Tibet is the birthplace of mysticism, contact with a secret religion will help us understand the roots of many mystical systems. Indeed, according to one theory, it was in Tibet that representatives of ancient civilizations settled, and from there esoteric knowledge was spread throughout the whole Earth.
Speaking about the beliefs of Tibet, we first recall Buddhism. At the same time, it is possible that someone does not know that the Tibetan lands were the cradle of another religion - for a Western person far away, alien and at times even frightening. Bon is an ancient Tibetan religion. Her name speaks for itself: it literally translates as "whisper", "hum", "repeat the ritual." In fact, it is: great attention in religion is paid to the rites of magic on the verge of shamanism.
Recently, many scholars were completely convinced that the most ancient religion in Tibet is the cult of bon. But that all changed on the day when archaeologists discovered the Touen - Houang caves of the 8th - 10th centuries. This event not only turned the view of religious scholars about the history of ancient Tibet, but also lifted the veil of an even greater mystery. What did the cave Touen - Houang hide in for hundreds of years? Scientists discovered in it incredibly ancient manuscripts, the study of which made it possible to find out that even before the existence of Bon, Tibetans had religion. This means that Tibetan civilization is more ancient than it could have been supposed.
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Temple in Tibet
Tibetan Buddhism is one of the most popular, unique, and incredibly fascinating branches of Buddhist teaching
Gradually weakening in their historical homeland - in India, in the 7th century, Buddhism began to flow straight into Tibet, but it was not immediately possible to take root in these parts. In the VII-IX century in Tibet dominated the indigenous religion of Bon, which means "sing", "recite". Her main gods were Earth and Sky. Shamanism flourished, people believed in numerous spirits (spirits of lakes, rivers, mountains) and evil demons. Specially trained people - priests - communicated with these spirits: appeaseed some and tried to defeat others. Religion Bon exists in Tibet to this day.
The emergence of Buddhists in Tibet changed the course of both religions: Buddhist and Bon. Borrowing ideas from each other, they entwined together, giving birth to a new religion - Tibetan Buddhism. It was a kind of symbiosis of the Indian Buddhist tradition with the Bon religion. XI-XII century is a new stage of development of Buddhism in Tibet. After a brief confrontation with the "extreme" followers of the Bon religion, the Buddhist tradition settled firmly in these places, predetermining the vector of their further cultural development. The monasteries where the monks lived spread over the whole territory.
For several centuries, Buddhism in Tibet is firmly rooted: harmoniously intertwined with the religions that existed there, merged with the local mentality, becoming its main religion. Manuscripts and relics were brought from India, Buddhist schools were formed on the basis of large monasteries, monks appeared. The modern European world often calls Tibetan Buddhism Lamaism, but this is not quite true, because this concept does not reveal, does not fully cover all the features of this religion, and the lama may not be a monk.
This teaching has undergone many changes, its key thoughts have changed over time, but still the foundations have remained unshakable and have survived to the present day. In contrast to traditional, Tibetan Buddhism, due to mixing with different cultural traditions of the local population, attaches great importance to rituals. In it, the usual Buddhist concepts mixed with all sorts of magic, rituals, divination. They penetrated into the life of any person, one way or another connected with religion: from monks to ordinary laity. The Buddhist teachings of Tibet have their own language, historical manuscripts, various practices and - most characteristic - the pantheon of gods. Gods of various levels are worshiped: Buddha, saints, deities, personal patrons, bodhisattvas, deities who can defeat evil spirits, demons.
By the nature of the flora and vegetation, China is sharply divided into two parts (approximately diagonally from the southwest to the northeast) - the arid, central Asian part and the humid, East Asian part, with the tropical region adjoining it from the south. At the same time, the tropical part of China is geographically strongly gravitating not to East, but to Southeast Asia, which includes Indochina on the Asian continent with the Malacca Peninsula, and then in the south of the islands of Indonesia, the Philippines, and New Guinea, by botanical features.
Dry desert spaces of Inner Mongolia, Xinjiang and Tibet are located to the north-west of this line, which runs from the Khingan Mountains almost in a straight direction to the eastern end of the Himalayas, and to the south-east are areas with a humid monsoon climate and mainly with temperate forest vegetation. subtropical, and in the extreme south and tropical type. An interesting feature of the flora of the monsoon part of China is the abundance of large, species-rich genera, especially woody plants. The number of genera comprising about 20-50 species reaches 60. The distribution of vegetation in the East Asian part of China, of course, is generally subordinated to climatic zonality, but the latitudinal zonality of the vegetation cover is not so distinct as, for example, on the plains of Europe or Siberia . China is a mountainous country, the direction of the ranges, their height, the location of the river valleys here are very complicated and whimsical. Therefore, only schematically it is possible to outline the latitudinal zones of vegetation, to a great extent masked by the altitudinal zonation of vegetation in the mountains.
World vacation travel - Nature - History - Summer - Monument - Heritage - Religion - Landscape - Museum - Exotic - Culture - Ancient - Reserve - Buddhist style - Temple - Buddhism - Travel Asia - Tibetan - Tibet - China - Architecture - Mountain.
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Probability Distributions
Probability Distributions
February 25, 2018
1. Idea
In a previous post, I explained Bayes Theorem and the way it works. In this post, I will try to sketch some basic information about probability distributions and their features, as they represent a cornerstone in Bayesian inference.
From its name, a probability distribution is a function, explains a distribution of different possible probabilities of a given hypothesis.
For example, if I ask you to guess the outcome of tossing a fair coin, what will be your answer? As you do not know the result yet, you may guess the outcome will have equally likely chance to be a head or a tail. Great! your guess represents a probability distribution called Binomial distribution, and it is visualized in the below figure.
Note here that the summation of all possible probabilities of the above experiment is equal to 1. I.e.:
P(Head) + P(Tail) = 1
Similarly, we can predict the outcome of rolling a die, or the marital status of a woman in Sydney.
Note here that all of the above distributions are probability distributions, as long as each distribution’s possible values summing up to 1.
2. Significance
Probability distributions are extremely important in data science. In the following subsections, I will try to list some popular usages of them.
2.1 Probability Distributions Are Functions
The prime importance of probability distributions is that they are very well-formed functions. As you can imagine, the basic mission of statisticians and/or data scientists is to find functions (i.e. relationships between data variables). Therefore, and because probability distributions are well-defined functions, with different characteristics and features that have been studied for decades, they considered as a fundamental way of representing, analyzing, and visualizing data variables.
2.2 Expressing Uncertainty
The second significance of probability distributions is that each of them can mathematically express our uncertainty about an event, experiment, or hypothesis. For example, if you toss a coin, you can not know the result (Head or tail) before the coin lands. Nevertheless, you can draw all possible outcomes, each with certain probability, using a probability distribution. The following figures shows the difference between uncertainty and certainty.
100% Head
As another example, suppose you have a list of heights (in inches) of random sample of students in a high school: \(heights=\{65.78, 71.52, 69.40, 68.22\}\), and you want to model these observations using a continuous function. The first logical way of thinking is to assume the heights vector is following a normal probability distribution, and compute both mean and variance of the sample data to visualize your probability function:
Expressing uncertainty plays basic role in machine learning, as it enables us to make predictions of events which haven’t happened yet (e.g. earthquakes).
2.3 Exploring Statistics
The third benefit of probability distributions is that once you define the distribution your data is drawn from, you can easily find interesting statistics (or facts) about your data. For example, given the above heights example, once you found a probability distribution (e.g. normal distribution) to express it, you can answer questions like: what is the maximum height? minimum height? variance between heights? most common height? and so on.
2.4 Data Imputation
Another common application of probability distributions is to impute (i.e. fill-in) missing values in your data. Suppose for example you got a vector of heights, but with some missing values:
\begin{equation} heights=\{65.78, 71.52, ?, 68.22, ?, 68.70, ?, 70.01\}\end{equation} A common technique to fill-in these missing values is to draw these missing points multiple times using one probability distribution with different parameter settings, analyze multiple versions of your data, and finally integrate all versions into one final version (maybe with minimum variance or narrowest confidence interval). This technique is called multiple imputation, and it is widely used to fill-in missing data values.
2.5 Making Predictions
The fifth usage of probability distributions is to make predictions of events and hypotheses, using our believes and/or some historical data. Common approaches of calculating predictions (or guesses) using probability distributions are Bayesian and Frequentist Inferences.
3. Components
There are multiple components of probability distributions, that outline their functionalities and applications. Anyone wants to use a distribution should learn about it’s specific components. In the following points, I will try to briefly cover some of the basic components of probability distributions.
3.1 Random Variables
A random variable is a numerical mapping of all possible outcomes of a random process, and a random process is a process we do not know it’s outcome until it occurs. For example, the random variable \(X\) of tossing a fair coin can be expressed as \(X=\{0,1\}\), where the outcome \(Head\) is mapped to 0 and the outcome \(Tail\) is mapped to 1.
Another example is rolling a die, where random variable \(X\) can be represented by \(X=\{1,2,3,4,5,6\}\), with each side of the die is encoded to its equivalent numerical value in vector \(X\).
As we saw before (in logistic regression post), there are two basic types of data variables: categorical (discrete) and quantitative (continuous). There are also two corresponded types of random variables: continuous and discrete random variables. Each type of random variables is represented by a specific class of probability functions.
3.2 Probability Mass Function (PMF)
Probability Mass Functions (PMF) are functions that describe probability values of discrete random variables \(X\). PMF(\(X\)) must sum up to 1 for all possible values of \(X\).
For example, if we compute the PMF of rolling a die, where random variable \(X=\{1,2,3,4,5,6\}\), we can draw PMF(\(X\)) as follows:
f_X(x)=Pr(X= x)\ \ \ and\ \ \ \sum_{x\in X} f_X(x)=1\tag{1}
A probability mass function (PMF) computes the probability that a random variable \(X\) can take any possible outcome \(x\in X\). In dice example, \(f_X(x=3)=0.17,\ f_X(x=1)=0.17,\ f_X(x=7)=0\). Note that the sum of all possible values of \(x\) equals to 1.
3.3 Probability Density Function (PDF)
As PMF describes probability values of discrete random variables, the probability density function (PDF) describes probability values of continuous random variables. An example of PDF is the one of normal distribution below:
Please note that for PDFs, the area under curve must sum up to 1.
3.4 Cumulative Distribution Function (CDF)
Beside PMF and PDF, there exist a third type of functions for both discrete and continuous variables. These are cumulative distribution functions (CDF). The CDF computes the cumulative probability up to a given value \(x\in X\). In case of discrete random variable, the CDF looks like this:
The green stepwise function above represents the CDF of rolling a die, and it is computed as follows:
F_X(x) &=Pr(X\leq x) \\
&=\sum_{x_i\leq x} Pr(X=x_i) \\
&=\sum_{x_i\leq x} p(x_i)
You can think of \(F_X(x)\) as summing up all probabilities upto value \(x\). For example:
F_X(x=3)= \sum_{x_i=1}^3 p(x_i)= 0.17+0.17+0.17=0.51
For continuous random variables, CDFs using integrals instead of summations, in order to compute the area under continuous PDF curves. The next figure shows an example of the normal distribution CDF.
&=\int_{-\infty}^x f_X(y)dy
where \(y\) is a dummy integration variable.
Please note that for continuous random variables, we integrate PDF(\(x\)) over given limits (say \(\{a,b\}\)) to obtain CDF(\(x\)), and we differentiate CDF(\(x\)) with respect to \(x\) to obtain PDF(\(x\)).
4. Moments
Each probability distribution function is defined by a set of coefficients (called moments). These moments represent important statistics that can be computed out of mass/density functions. The most important moments of probability distributions are listed below:
4.1 Expectation
The expectation \(E(X)\) of probability distribution is the average (i.e. mean) value of it’s random variable \(X\). It is also called the first moment. The term “expectation” is used here to express the value used to represent the whole distribution in probabilistic inferences. Other names of expectation are “point estimate” or “best guess“. It is noted as \(E(X)\) or \(\mu(X)\).
4.2 Variance
The variance \(V(X)\) of probability distribution expresses how far a set of random numbers \(x\in X\) are spread out from its expectation \(\mu(X)\). It’s also called the second moment. It is noted as \(V(X)\) or \(\sigma(X)\).
4.3 Precision
Precision \(\tau(X)\) is the reciprocal of the variance \(\frac{1}{\sigma(X)}\). It is used to measure how close a set of random numbers \(x\in X\) are to their average value \(\mu(X)\). High precision values usually used as indicator of good probabilistic models.
4.4 Median
The median value of a set of random numbers \(x\in X\) is the value that separates the higher half from the lower half of vector \(X\). For example, in dataset \(\{0,1,2,3,4,5,6\}\) the median value is 3.
4.5 Mode
The mode value of a set of random numbers \(x\in X\) is the most common (i.e. repeated) value in the data set. It is also the data point where PDF reaches its local (or global) maxima. For example, in dataset \(\{0,1,5,5,7,2,9,8,5\}\) the mode value is 5.
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10 March 2017, Comments: 0
This week we have been very busy preparing for SATS. We’ve had separate groups to give us more confidence to answer the questions.
In Maths we have been working on reflection. We did this using a mirror which shows the reflection of a shape on the other side. Another of our learning objectives was to estimate, measure and draw angles. We have calculated obtuse, reflex and acute angles using a protractor to help. First we estimated them and then found out the correct answer.
At the moment we are reading a class novel, sharing a book 1 between 2. It is called Friend or Foe and is set during the war. It’s about a boy who gets evacuated to Devon. We have been making inferences from the text and answering questions to do with the text.
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AMT Atmospheric Measurement Techniques AMTAtmos. Meas. Tech. 1867-8548 Copernicus Publications Göttingen, Germany 10.5194/amt-14-983-2021A novel rocket-borne ion mass spectrometer with large mass range: instrument description and first-flight resultsROMARA instrument description and first results StudeJoan AufmhoffHeinfried SchlagerHans RappMarkus ArnoldFrank StrelnikovBoris Atmospheric Physics, Ludwig-Maximilians-Universität München (LMU), Munich, Germany German Aerospace Center (DLR), Institute of Atmospheric Physics, Oberpfaffenhofen, Germany Leibniz-Institute of Atmospheric Physics (IAP), Kühlungsborn, Germany Max Planck Institute for Nuclear Physics (MPIK), Heidelberg, Germany Joan Stude ( 14 2 983993 22May2020 24June2020 19November2020 28November2020 Copyright: © 2021 Joan Stude et al. 2021 This work is licensed under the Creative Commons Attribution 4.0 International License. To view a copy of this licence, visit article is available from full text article is available as a PDF file from Abstract
We present a novel rocket-borne ion mass spectrometer named ROMARA (ROcket-borne MAss spectrometer for Research in the Atmosphere) for measuring atmospheric positive and negative ions (atomic, molecular and cluster ions) and positively and negatively charged meteor smoke particles. Our ROMARA instrument has, compared to previous rocket-borne ion mass spectrometers, a markedly larger mass range of up to m/z 2000 and a larger sensitivity, particularly for meteor smoke particle detection. The major objectives of this first ROMARA flight included the following: a functional test of the ROMARA instrument, measurements between 55 and 121 km in the mass range of atmospheric positive and negative ions, a first attempt to conduct mass spectrometric measurements in the mass range of meteor smoke particles with mass-to-charge ratios up to m/z 2000, and measurements inside a polar mesospheric winter echo layer as detected by ground-based radar. Our ROMARA measurements took place on the Arctic island of Andøya, Norway, at around noon in April 2018 and represented an integral part of the polar mesospheric winter radar echo (PMWE) rocket campaign. During the rocket flight, ROMARA was operated in a measurement mode, offering maximum sensitivity and the ability to qualitatively detect total ion signatures even beyond its mass-resolving mass range. On this first ROMARA flight we were able to meet all of our objectives. We detected atmospheric species including positive atomic, molecular and cluster ions along with negative molecular ions up to about m/z 100. Above m/z 2000, ROMARA measured strong negative-ion signatures, which are likely due to negatively charged meteor smoke particles.
Meteor smoke particles (MSPs) are of considerable current interest since they have several interesting atmospheric roles. MSPs may act as sites of heterogeneous reactions involving atmospheric trace gases and ions. Moreover, MSPs act as nuclei in the formation of mesospheric water ice clouds and as nuclei in the formation of the stratospheric sulfuric acid and nitric acid aerosol layers , which have an impact on ozone and climate . MSPs may also influence the charge balance of the lower ionosphere by acting as scavengers of free electrons and ions . Furthermore, electrically charged MSPs have been proposed to play a potential role in the formation of polar mesospheric winter radar echoes (PMWEs) .
MSPs are formed by the ablation of meteors or interplanetary dust particles in the upper atmosphere, as was originally hypothesized by . The ablation process causes meteoric vapours to be released, mostly at altitudes around 90 km in the mesopause region, during entry into the atmosphere at high velocities . Hereafter, such vapours undergo gas phase reactions with atmospheric gases and ions and ultimately recondense, leading to tiny aerosol particles . termed these particles meteor smoke particles and conducted model simulations predicting an MSP layer to be present between 70 and at least 100 km, peaking at around 85 km. The predicted MSP radii range is from 0.2 to 10 nm, corresponding to hundreds to millions of atomic mass units (u) (Fig. ). For example, at 85 km, MSPs with radii larger than 0.2 nm have a predicted number concentration of 7 × 104 cm-3. The meteor vapours, which lead to MSP formation, are to a large part composed of metal and silicon atoms formed mostly via ion–molecule reactions with atmospheric positive ions. Early rocket-borne ion composition measurements of the whole suite of the most abundant meteoric positive-ion species (Fe, Mg and Si) and their isotopes revealed an ion composition similar to the elemental composition of chondrites . The mass density of ordinary chondrites is about 3.5 g cm-3 ; however, the ablation process might form particles with lower densities of 2.0 g cm-3, as assumed by and .
Comparison of different relationships between molecule mass and size with data from and .
Using the above values in Fig. and assuming a spherical MSP particle of 0.3 nm radius, one would estimate an effective mass of about 135 to 240 u. The first observational indications for the presence of such negatively charged nascent MSPs (>473 u) have been obtained from rocket-borne measurements of ion mass spectrometers by under twilight conditions. Meanwhile several rocket-borne electrostatic probe measurements provided evidence for larger MSPs than measured by the ion mass spectrometers . Even some of the first direct information on the chemical nature of MSPs was obtained by rocket-borne photoionization measurements. It was found that the ionization potential of MSPs is somewhat similar to that of Fe and Mg hydroxide clusters . Besides those direct in situ measurements, more indirect measurements of MSP signatures in the spectra of incoherent scatter radars were reported by several investigators . Also, satellite measurements with the Solar Occultation For Ice Experiment (SOFIE) have provided clear evidence of MSPs in solar occultation extinction measurements .
The present paper reports on the search for MSPs using a novel rocket-borne ion mass spectrometer having an increased mass range of up to m/z 2000 and an increased sensitivity. Importantly, the rocket flight was determined to penetrate a PMWE layer, which which was indeed accomplished. Details about the PMWE campaign will be given in and . Here we give a thorough description of the ROMARA instrument and a brief presentation of the ion and MSP data.
Instrument description
The ROMARA instrument is a cryogenically pumped quadrupole mass spectrometer based on earlier designs from the Max Planck Institute for Nuclear Physics (MPIK) . Cross sections of the instrument and mass spectrometer are shown in Fig. . Ions enter the instrument through a knife edge intake orifice with a radius of 0.5 mm on the tip of a double cone. The design allows one to sample the atmosphere in front of the shock due to the supersonic speed of the payload. A quadrupole lens 36 mm in length is mounted between the intake orifice and quadrupole, with skewed tips for a placement as close as possible to the intake cone. The quadrupole mass filter has a length of 115 mm and uses cylindrical rods 2.4 mm in radius. The field radius r0 between the rods is given by a ratio of rrod/r0=1.128, as recommended by .
(a) Detailed cross section of the ROMARA mass spectrometer in flight configuration. (b) Cross section of the complete ROMARA instrument in launch configuration. CEM: channel electron multiplier; FEE: front-end electronics; DPU: data processing unit.
Ions passing the mass filter are detected by a channel electron multiplier (CEM) placed in the centre of the instrument in the line of sight of the intake orifice. The quadrupole and detector are almost completely surrounded by the cryopump, which also serves as a mechanical support. A cap seals the instrument intake during storage and launch and is jettisoned before the measurements begin. For this purpose, a spring loaded bayonet ring is turned by pyro-actuators to release the cap. Inside the cap, a commercial ion source (electron ionization, Hiden Analytical 205011) allows one to calibrate and test the instrument on the ground and monitor operation during launch until the cap together with the ion source is removed. To increase ion transmission, independent bias potentials can be applied to the intake cone, quadrupole lens and rods (see Sect. ). To maximize detection efficiency, especially for heavy ions, the CEM (Photonis 4830-MgO) is coated with magnesium oxide and biased to ±1800 V with a constant voltage across the CEM of about +2700 V. Measuring positive ions requires all bias voltages to be negative and vice versa. For an alternating operation of the instrument between positive and negative ions, the bias voltages are switched in the dead time between the spectra.
The cryopump is a bath-type design using gold-plated cooling surfaces. A heat shield, cooled by the evaporating cryogen, is placed between the reservoir and outer shell. Liquid helium is most readily available cryogen; however, it evaporates rather quickly and the reservoir would be depleted in about 1 h. Longer standby times can be achieved using neon because of its higher vaporization enthalpy. Thus, the rocket can be safely prepared for launch and the probability of meeting the desired atmospheric conditions during a day of work is higher. On the day of launch, a total standby time of 7 h with subsequent successful operation was achieved. We produced liquid neon at the launch site by liquefying neon gas with liquid helium. A disadvantage of using neon as the cryogen is the inefficient pumping of hydrogen, helium and neon itself due to their boiling points being below or at that of neon. While parts of these gases are trapped in the frozen air building up on the cooling surfaces, the remaining gas (mostly helium) could accumulate above a critical pressure. However, for our combination of intake size and duration of flight this is not of concern.
A reinforced bulkhead holds the complete construction of electronics, quadrupole and cryopump. The bulkhead further seals the main structure against the atmosphere and water during splashdown. The front-end electronics (FEEs), data-processing unit (DPU) and batteries are housed in the main structure at 1.5 bar absolute nitrogen pressure to safely handle high voltages. The whole instrument is 856 mm in length with a diameter of 356 mm and a total mass of about 50 kg.
Principle of operation
A quadrupole mass spectrometer separates ions by their mass-to-charge ratio (m/z) by applying electrical fields along a central drift path of ions. These fields are ideally hyperbolic but are often approximated by cylindrical electrodes, the rods, circularly arranged along their length. The required fields are formed by radio frequency (VRF) and static (VDC) potentials with opposite polarity at neighbouring rods. Thus, opposing rods are electrically connected and form two pairs of rods. Ions of a certain m/z retain stable trajectories, pass the quadrupole and can be detected at the exit, while other ions collide with the rods and are lost. To pull ions in between the rods, a constant bias voltage VB is applied to all rods, i.e. Vrod=VB±[VDC+VRFcos(ωt)]. The quadrupole allows two modes of operation: an RF-only mode and a line mode. In RF-only mode, VDC is set to zero. With increasing VRF, lower masses are rejected until a maximum VRF is reached. The count rate in the detector will thus eventually drop for each ion mass and produce a step in the recorded mass spectrum, which can be analysed for width and height. Ions with masses above the mass given by the maximum VRF still pass the quadrupole but can not be mass analysed. This is often described as a high-pass mass filter, although it is actually a wide bandpass, as illustrated in Fig. . We simulated transmission curves for different mass settings of the quadrupole and different ion masses using SIMION® to model the electrical fields and individual ion trajectories. Collisions with the background gas or charge exchange processes were omitted. For each ion mass per charge and mass per charge setting of the quadrupole, a population of 3000 ions is started inside the intake orifice with a constant velocity of 980 m s-1 (i.e. rocket velocity, v), an angle of attack of 2.2 and a uniform conical direction distribution with an opening angle δ defined as δ=2atan3kTmv, where k is the Boltzmann constant, T is temperature (180 K) and m is ion mass.
SIMION® simulation of ROMARA quadrupole for heavy-ion transmission in RF-only mode for an angle of attack of 2.2.
It is evident that for low VRF values, and hence mass settings of the quadrupole, only small fractions of ions above 104 u (1.2 nm radius) pass the quadrupole to the detector. Ions with sufficient masses and thereby sufficient kinetic energy do not respond efficiently to the small applied fields. In this case the intake orifice and exit aperture act as collimator and limit the detector flux to trajectories smaller than 0.85 from the central axis. The instrument thus mass analyses particles up to m/z 2000 and detects the presence of particles up to about m/z 3 × 105 (3 nm radius). For the line mode with an additionally applied VDC, this effect is much smaller and can be neglected. For the quadrupole to operate in line mode, the VDC is set to a constant ratio to VRF and thus forms a narrow band pass mass filter. With increasing voltages, the band pass window is moved from low to high masses and a line spectrum can be recorded. The ratio of VDC to VRF determines the size of the band pass window and thus resolution and sensitivity. The voltage applied to the quadrupole lens always corresponds to VRF only. This minimizes ion losses at the entrance to the rod system when the quadrupole is operated in line mode.
Ion sampling from the atmosphere
The payload moves at supersonic speeds through the atmosphere, developing a shock in the ram direction. The knife edge double cone is designed to sample ions in front of the shock, avoiding perturbations and possible breakup of weakly bound ions. The shock was simulated with the direct Monte Carlo simulation software DS2V under conditions of a standard atmosphere with a composition of nitrogen and oxygen (NRLMSISE-00) and rocket speeds appropriate for our flight. Figure a shows the rocket speed, temperature and number density for different altitudes used in the simulation. Figure b shows the relative air speed and the increase of temperature and number density 1 cm upstream from the intake orifice. Up to 80 km the ratios stay at about unity. Above 80 km the shock starts to detach from the payload and the number density and temperature begin to increase while the relative air speed decreases. Values change roughly by a factor of 2 at 100 km altitude as compared to undisturbed conditions. Particles with much larger masses, such as MSPs, will be less affected by the shock formed by air molecules and thus penetrate it more efficiently.
(a) DS2V simulation input parameters from the NRLMSISE-00 Atmosphere Model. (b) DS2V simulation results 1 cm upstream of the inlet orifice plotted as a ratio to ambient values of relative air speed, atmospheric temperature and number density.
As front-end electronics we use modified electronics from the MPIK originally developed for aircraft operations, e.g. the quadrupole power supply. The electronic pulses from the CEM are transformed by an Amptek A111F charge amplifier to digitally countable pulses. To control the front-end electronics and process the data we use a microprocessor/FPGA system from National Instruments (sbRIO-9637). During ground preparation the system can be remotely controlled and updated if necessary. After launch, the system is controlled by a timeline programme that does not allow further interactions. The data are transmitted via the rocket service module but are also stored on an internal SD card. The data volume is about 10 kB per spectrum. The instrument is self-powered using lithium iron phosphate batteries, which allow approximately 1.5 h of operation. A mass spectrum is divided into 4096 mass channels with a dwell time of 300 µs. This results in a total time of 1.274 s, including 0.045 s of dead time at the beginning of each spectrum. The total time of a spectrum, and thus height resolution during flight, is mostly limited by the VRF oscillator. The oscillator runs at about 1.4 MHz with a maximum amplitude (VRF) of 1750 V.
The bias voltages of the quadrupole lens and the rods were calibrated using positive xenon ions. The intake cone potential was set to zero and therefore to the payload's ground. We found an optimum transmission if the rods and quadrupole lens have potentials of -50 V and -20.5 V respectively. For negative ions the same absolute values were used. During tests we observed a significant loss of transmission if both voltages were equal. For the mass calibration of the instrument we used 4 eV ions of neon, krypton, xenon and perfluorotributylamine (PFTBA, Heptacosa, FC-43), allowing a calibration up to m/z 502. In Fig. a we show measurements of Kr and Xe ions, the cumulative distribution function (CDF) fits of the ion mass steps, the reconstructed Gaussian peaks and the respective isotope lines from the National Institute of Standards and Technology (NIST). The mass resolution m/Δm at 50 % peak height was determined to be about 17.5 (5 u peak width for Kr) and the theoretical mass range from m/z 5 to m/z 2075. In the lower panel we show the standard spectrum of PFTBA from NIST data and the measured spectrum from ROMARA. The NIST spectrum was converted to an RF-only version by summing up all single peaks in the NIST data. The measured ROMARA spectrum was normalized to the m/z 69 peak and shows good agreement for the major steps of PFTBA up to m/z 502. Steeper falloffs between the major PFTBA steps are a result of typical hydrocarbon contaminations of the ion source (steps <m/z 300, Fig. a). In cases where there are many small peaks close to each other, the ROMARA spectrum turns into a continuous slope because of the limited mass resolution.
(a) RF-only spectrum of Kr and Xe, CDF fits and equivalent Gauss peaks. (b) ROMARA RF-only measurement of PFTBA and NIST data of PFTBA.
Positive-ion mass spectra at four different altitudes during ascent in logarithmic scales. Spectrum (a) shows the residual gas spectrum from the internal ion source before ejecting the cap. Spectrum (b), (c) and (d) show natural ambient ions. The vertical resolution for spectrum (b), (c) and (d) is 1426, 1270 and 678 m respectively.
The noise level of the instrument is mostly determined by the oscillator and the switching between positive- and negative-ion mode leading to increased counts at the beginning and end of each spectrum, especially in the negative-ion mode. On the launch pad with the instrument operating nominally and the ion source switched off, the average noise floor over a whole spectrum was 9 Hz in positive-ion mode and 240 Hz in negative-ion mode, well below our one-count limit of 3.3 kHz.
Measurement and discussion Launch conditions
The main launch criteria were determined by the MAARSY radar , looking for polar mesospheric winter echoes. The radar pointed alternately along the rocket trajectory and to the zenith (see , for details). In the days before launch, several echoes were detected but other launch criteria, e.g. for the sea recovery, were not met. On 13 April 2018 at 09:44:00 UTC, ROMARA was launched directly into an echo between 78 and 80 km altitude, with weaker echoes visible just before at around 65 and 70 km. After separating the nose cone at 52.2 km, the instrument cap was jettisoned at 54.5 km and the ROMARA measurements began. At 60.0 km the motor was separated from the payload. The payload hit the echo at its decaying tail before reaching an apogee of 121.4 km. The electron density was measured with the on-board wave propagation experiment but also with the Saura MF radar about 20 km south of the launch site. The ionosphere was moderately disturbed with a simulated riometer absorption of 0.26 dB at 27.6 MHz. At the given time and location, a solar zenith angle of 61.6 is calculated; the direction of the launch was 330 azimuth (northwest by north).
Ion measurements
The instrument was operated in RF-only mode throughout the flight and measured natural ions during the ascent from 54.5 to the apogee at 121.4 km but also on the downleg in the rocket wake. The intake cone was applied with a constant 0 V bias and thus was at payload potential during the whole flight. In this instrumentally oriented paper, we present eight exemplary mass spectra, obtained during rocket ascent: four positive and four negative. These include two test spectra obtained just prior to cap ejection and six ambient ion spectra. A more detailed analysis of the ion measurements will be presented elsewhere. The internal ion source was operated up to 49 km altitude and was switched off before the ejection of the cap. Other spectra were chosen around 70 and 106 km. At 70 km the sampling conditions are ideal with the shock wave being well attached to the intake cone as the simulations of Fig. show. Thus, ions enter the instrument with minimum disturbance and under small angles of attack (α2.2). In contrast to 70 km, the spectrum at 106 km is much more affected by the shock; it is now completely detached and the angles of attack are considerably larger (α11.4).
Raw count rates craw were corrected for detector dead time τ and angle of attack α. The angle was provided by the rocket operator, and the dead time was taken from the A111F data sheet with τ=350 ns, giving the corrected count rate c: c=craw(1-crawτ)cos(α). In Figs. and we included an eight-channel mean, as the original data are noisy. The count rates given hereafter refer to the eight-channel running mean count rate.
Positive ions
Figure a depicts a positive test spectrum obtained at 46.8 km, prior to cap ejection, with the internal ion source in operation. In contrast to the calibration data of Fig. , where a laboratory power supply for the ion source is used, the internal power supply provides a less stable current and typical residual gas steps are not clearly visible. However, the count rate clearly decreases from about m/z 28 up to m/z 300, typical for leaking air and contamination, e.g. hydrocarbons, in the ion source and cap. The maximum count rate is 636 kHz for below m/z 28.
Figure b depicts the spectrum at 55.7 km, just after ejecting the cap, and serves to show that no residuals are present in the mass spectrum. Some counts of the same type as in the spectrum of Fig. c are already visible.
Figure c depicts a spectrum starting at 69.2 km altitude with ambient atmospheric positive ions. It has a maximum mean count rate of about 26 kHz and a maximum of m/z 76, which is most likely due to the expected proton hydrate H+(H2O)4[73 u]. This proton hydrate of fourth order has been measured previously often together with H+(H2O)3[55 u] and higher orders. However, in this particular spectrum, a step is found at around m/z 49, which is thus more likely due to NO+(H2O)[48 u]. A less defined step around m/z 58, with only few counts per mass channel, likely corresponds to H+(H2O)3[55 u].
In Fig. d a spectrum at 106.3 km is shown with a similar maximum count rate of 26 kHz with a step around m/z 28. This is consistent with NO+[30 u] or O2+[32 u] as the most dominant ions at that altitude.
It is noticeable that the spectra do not start at maximum count rates. This is qualitatively the same effect as shown by the 100 u curve in Fig. .
None of these positive-ion spectra indicate the presence of heavy positive ions.
Negative ions
In Fig. we show characteristic negative-ion spectra for altitudes similar to those in Fig. . The spectrum in Fig. a is taken before cap ejection at an altitude of 48.3 km with the ion source operating. As expected, negative ions are not present, as they are not formed by the ion source (electron ionization) in the cap.
Negative-ion mass spectra in linear scales during ascent, at similar altitudes as the positive-ion mass spectra. In spectrum (a) the instrument is still sealed to the environment, while in spectra (b), (c) and (d) natural ambient ions are present. The vertical resolution for spectrum (b), (c) and (d) is 1431, 1245 and 688 m respectively.
Figure b shows the spectrum beginning at 54.2 km altitude, in which the cap was ejected. Before cap ejection the count rate is at the same low noise level as in Fig. a. Instantaneously, with cap ejection around m/z 400, the count rate increases to a plateau around m/z 560 with a maximum count rate at 200 kHz. Hereafter, the count rate decreases to about 50 kHz showing some minima and maxima, possibly related to rocket spin. Towards the end of the spectrum the count rate remains at about 50 kHz indicating ions beyond our mass range of m/z 2000.
Figure c at 70.5 km altitude contains light negative ions with a maximum count rate of 200 kHz, exceeding the positive count rate almost 10-fold. The count rate at the end of the spectrum is about 100 kHz. The inset is a blow-up of the small-ion mass range to m/z 100, indicating the presence of numerous unresolved mass steps with high count rates even at the smallest mass channels. Potential mass steps can be found around m/z 24, m/z 48, m/z 58, m/z 65 and m/z 79. These steps could be caused by CN-[26 u], C1-(H2O)[53 u], CO3-[60 u], HCO3-[61 u], NO3-[62 u] and CO4-[76 u], some of which have been previously measured by and . The heavy-ion signature is now clearly modulated by the rocket spin (3.6 Hz) with the maxima being about 0.27 s apart and thus requiring 4.5 modulations of the incident ion flux within a full spectrum. This can only be caused by asymmetries in the ion optics or at the intake orifice under angles of attack larger than zero. We therefore interpret this signal as negative ions with masses above our mass range of m/z 2000. Other origins of this signal, such as stray UV light, neutral particles or a pressure effect inside the instrument, can most likely be ruled out. While UV light or neutral particles could trigger false counts, this would also be visible in the positive-ion mode and was tested for UV light in the laboratory. A pressure effect inside the instrument due to the higher voltages of the negative-ion mode would lead to counts that directly correlate to decreasing ambient pressure, but instead we measured an increase from about 50 kHz in Fig. b to about 100 kHz in Fig. c.
In Fig. d at 105.6 km altitude, increased levels of noise can be seen with no obvious small- or large-ion signatures. However, the largest spikes at m/z 1688, m/z 1245, m/z 778 and m/z 308 are 0.27 s apart and thus indicate some heavy ions again modulated by the rocket spin.
Charge balance
It is usually assumed that the atmosphere is quasineutral such that the positive-ion density balances the negative-ion and electron density: N+=N-+Ne. At around 70 km we measured a maximum count rate of 26 kHz for positive ions and around 300 kHz for negative ions (light ions + heavy ions). Count rates may be converted to ion densities by the air column swept out through the intake orifice and rocket velocity: N=c/(πr2v). This leads to ion densities of N+=32 cm-3 and N-=379 cm-3. In the electron density at 70 km was about 500 cm-3, suggesting about 27 times more negative charges than positive. At around 55 km the situation is even worse with very few positive counts. The simple conversion of counts to ion density above, does not consider effects such as the transmission efficiency of ions between intake and CEM; the absolute detection efficiency of the CEM and the payload potential, which might explain the imbalance of charges. The transmission efficiency of the quadrupole in RF-only mode is assumed to be close to unity and should be equal for both charge states as the potential amplitudes are identical between the positive- and negative-ion mode. The absolute detection efficiency across the mass range of our instrument for the MgO-coated CEM is presently unknown. For the same CEM model but without MgO coating and similar ion energies, found the absolute detection efficiency for oxygen to be about 0.6 for positive ions and 0.7 for negative ions. Heavier atomic ions generally have a lower detection efficiency , e.g. xenon with 0.15 at 2 keV, but publications are scarce for heavier molecules. Measurements from on microchannel plates indicate a rather low detection efficiency of around 0.02 for molecules of 2352 u at 2 keV. A positive payload potential and therefore a positive potential on our intake cone could decrease positive-ion count rates and increase negative-ion count rates. Such a potential is the result of currents to and from the payload interacting with the surrounding plasma, mainly dominated by free electrons . At 70 km and below, the electron density is low and the presence of heavy negative ions as carriers of negative charges could eventually lead to a positive payload potential as they are much slower than free electrons and the dominating positive ions. However, other effects such as photoemission or triboelectric charging could lead to positive charging. In the D-region, payload charging has been known as a major error source for quantitative rocket-borne measurements for a long time . Hence, the effect of payload charging on the presented observations, with its apparent departure from charge neutrality, needs to be investigated in more detail. A full treatment of payload charging effects is beyond the scope of this investigation and will be dealt with in detail in a future publication.
With ROMARA, we successfully re-vitalized an instrument concept to make mass spectrometric measurements in the mesosphere and lower thermosphere. With its extended mass range for MSPs, ROMARA detects ambient atmospheric positive and negative ions up to m/z 2000 and in addition measures the total count rate of ions with masses above m/z 2000. We have simulated the instrument's aerodynamic and ion–optical behaviour and conducted laboratory measurements for the characterization of ROMARA. The first ROMARA flight, which took place at noon on 13 April 2018 and reached an apogee of 121.4 km, was successful in detecting ambient atmospheric positive and large negative ions. After the flight the instrument was recovered nearly undamaged. Six exemplary mass spectra of ambient atmospheric positive and negative ions, measured during rocket ascent, are shown in the present paper and demonstrate the successful application of an instrument to conditions in the middle atmosphere.
The most important scientific results of the ROMARA data presented here concern the detection of large negative ions and a strong indication for the absence of large positive ions. Most likely, the large ions are actually negatively charged meteor smoke particles with radii of about 0.6 to 2.5 nm (m/z 2000 -m/z 105). Besides large negative ions, small negative ions with masses mostly below m/z 150 were also detected at 70 km. At 106 km, no negative ions were detected. These findings are consistent with previous measurements. Positive ions measured at 70 km are mostly hydrated cluster ions up to m/z 73. At 106 km the detected small positive ions have mass numbers around m/z 30. Again, this is consistent with previous measurements that found H+(H2O)3[55 u] and H+(H2O)4[73 u] to dominate at 70 km and NO+[30 u] and O2+[32 u] to dominate at 105 km. Large positive ions were not detected at 70 nor at 105 km above our measurement threshold. From our large-ion measurements at 70 km the following conclusions may be drawn. The presence of large negative ions suggests that at 70 km electron attachment to neutral MSPs was sufficiently fast and neutralization of negative MSPs by photodetachment and recombination with positive ions was sufficiently slow to allow a substantial fraction of MSPs to be negatively charged. The absence of positive MSPs suggests that neutralization of positive MSPs by collisions with free electrons was faster than positive MSP formation by uptake of positive ions.
Data availability
The data is available through the HALO database: .
Author contributions
JS was responsible for the following: investigation, methodology, formal analysis, project administration, software, visualization, and writing of the original draft;HA for the investigation, validation, software, and writing (review and editing); HS for supervision and writing (review and editing); MR for funding acquisition, supervision, and writing (review and editing); FA for conceptualization, validation, supervision, and writing (review and editing); an BS for conceptualization, and writing (review and editing).
Competing interests
The authors declare that they have no conflict of interest.
The authors wish to express their thanks to the mobile rocket base (MORABA) and Andøya Space Center (ASC) for their intense support and help. We would also like to thank Bernhard Preissler (), Robert Lindemann and Systemhaus Technik for their dedicated technical support. We further acknowledge discussions at working groups 414 and 437 at the International Space Science Institute (ISSI) in Bern, Switzerland.
Financial support
Project PMWE was funded by the German Federal Ministry for Economic Affairs and Energy and by the German Aerospace Center (DLR) (grant no. 50OE1402).
Review statement
This paper was edited by Troy Thornberry and reviewed by two anonymous referees.
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E., Mills, M. J., and Stockwell, R.: Meteoric smoke and H2SO4 aerosols in the upper stratosphere and mesosphere, Geophys. Res. Lett., 44, 1150–1157, 10.1002/2016GL072049, 2017. Hunten, D. M., Turco, R. P., and Toon, O. B.: Smoke and Dust Particles of Meteoric Origin in the Mesosphere and Stratosphere, J. Atmos. Sci., 37, 1342–1357, 10.1175/1520-0469(1980)037<1342:SADPOM>2.0.CO;2, 1980. James, A. D., Brooke, J. S. A., Mangan, T. P., Whale, T. F., Plane, J. M. C., and Murray, B. J.: Nucleation of nitric acid hydrates in polar stratospheric clouds by meteoric material, Atmos. Chem. Phys., 18, 4519–4531, 10.5194/acp-18-4519-2018, 2018. Kalashnikova, O., Horányi, M., Thomas, G. E., and Toon, O. B.: Meteoric smoke production in the atmosphere, Geophys. Res. Lett., 27, 3293–3296, 10.1029/1999GL011338, 2000. Keller, C. A. and Cooper, B. H.: Quantitative detection of low energy positive and negative ions with a channel electron multiplier, Rev. Sci. Instrum., 67, 2760–2764, 10.1063/1.1147104, 1996. Kopp, E.: Positive and negative ions of the middle atmosphere, Adv. Space Res., 12, 325–333, 10.1016/0273-1177(92)90488-J, 1992. Kopp, E., Ramseyer, H., and Björn, L.: Positive ion composition and electron density in a combined auroral and NLC event, Adv. Space Res., 4, 157–161, 10.1016/0273-1177(84)90279-5, 1984. Krankowsky, D., Arnold, F., Wieder, H., and Kissel, J.: The elemental and isotopic abundance of metallic ions in the lower E-region as measured by a cryogenically pumped quadrupole mass spectrometer, Int. J. Mass Spectrom., 8, 379–390, 10.1016/0020-7381(72)83024-9, 1972. Krems, M., Zirbel, J., Thomason, M., and DuBois, R. D.: Channel electron multiplier and channelplate efficiencies for detecting positive ions, Rev. Sci. Instrum., 76, 093305, 10.1063/1.2052052, 2005. La Hoz, C. and Havnes, O.: Artificial modification of polar mesospheric winter echoes with an RF heater: Do charged dust particles play an active role?, (1984–2012), J. Geophys. Res.-Atmos., 113, D19205, 10.1029/2008JD010460, 2008. Latteck, R., Singer, W., Rapp, M., Vandepeer, B., Renkwitz, T., Zecha, M., and Stober, G.: MAARSY: The new MST radar on Andøya-System description and first results, Radio Sci., 47, RS1006, 10.1029/2011RS004775, 2012. Latteck, R., Renkwitz, T., and Strelnikov, B.: D region observations by VHF and HF radars during a rocket campaign at Andøya dedicated to investigations of PMWE, Adv. Radio Sci., 17, 225–237, 10.5194/ars-17-225-2019, 2019. Lynch, K. A., Gelinas, L. J., Kelley, M. C., Collins, R. L., Widholm, M., Rau, D., MacDonald, E., Liu, Y., Ulwick, J., and Mace, P.: Multiple sounding rocket observations of charged dust in the polar winter mesosphere, J. Geophys. Res.-Space, 110, A03302, 10.1029/2004JA010502, 2005. Plane, J. M. C.: Atmospheric Chemistry of Meteoric Metals, Chem. Rev., 103, 4963–4984, 10.1021/cr0205309, 2003. Plane, J. M. C.: Cosmic dust in the earth's atmosphere, Chem. Soc. Rev., 41, 6507–6518, 10.1039/C2CS35132C, 2012. Plane, J. M. C., Saunders, R. W., Hedin, J., Stegman, J., Khaplanov, M., Gumbel, J., Lynch, K. A., Bracikowski, P. J., Gelinas, L. J., Friedrich, M., Blindheim, S., Gausa, M., and Williams, B. P.: A combined rocket-borne and ground-based study of the sodium layer and charged dust in the upper mesosphere, J. Atmos. Sol.-Terr. Phy., 118, 151–160, 10.1016/j.jastp.2013.11.008, 2014. Rapp, M. and Lübken, F.-J.: Modelling of particle charging in the polar summer mesosphere: Part 1 – General results, J. Atmos. Sol.-Terr. Phy., 63, 759–770, 10.1016/S1364-6826(01)00006-2, 2001. Rapp, M. and Thomas, G. E.: Modeling the microphysics of mesospheric ice particles: Assessment of current capabilities and basic sensitivities, J. Atmos. Sol.-Terr. Phy., 68, 715–744, 10.1016/j.jastp.2005.10.015, 2006. Rapp, M., Hedin, J., Strelnikova, I., Friedrich, M., Gumbel, J., and Lübken, F.-J.: Observations of positively charged nanoparticles in the nighttime polar mesosphere, Geophys. Res. Lett., 32, L23821, 10.1029/2005GL024676, 2005. Rapp, M., Strelnikova, I., and Gumbel, J.: Meteoric smoke particles: Evidence from rocket and radar techniques, Adv. Space Res., 40, 809–817, 10.1016/j.asr.2006.11.021, 2007. Rapp, M., Latteck, R., Stober, G., Hoffmann, P., Singer, W., and Zecha, M.: First three-dimensional observations of polar mesosphere winter echoes: Resolving space-time ambiguity, J. Geophys. Res.-Space, 116, A11307, 10.1029/2011JA016858, 2011. Rapp, M., Plane, J. M. C., Strelnikov, B., Stober, G., Ernst, S., Hedin, J., Friedrich, M., and Hoppe, U.-P.: In situ observations of meteor smoke particles (MSP) during the Geminids 2010: constraints on MSP size, work function and composition, Ann. Geophys., 30, 1661–1673, 10.5194/angeo-30-1661-2012, 2012. Robertson, S., Dickson, S., Horányi, M., Sternovsky, Z., Friedrich, M., Janches, D., Megner, L., and Williams, B.: Detection of meteoric smoke particles in the mesosphere by a rocket-borne mass spectrometer, J. Atmos. Sol.-Terr. Phy., 118, 161–179, 10.1016/j.jastp.2013.07.007, 2014. Rosinski, J. and Snow, R. H.: Secondary particulate matter from meteor vapors, J. Meteorol., 18, 736–745, 10.1175/1520-0469(1961)018<0736:SPMFMV>2.0.CO;2, 1961. Schulte, P. and Arnold, F.: Detection of upper atmospheric negatively charged microclusters by a rocket-borne mass spectrometer, Geophys. Res. Lett., 19, 2297–2300, 10.1029/92GL02631, 1992. Shipway, A. and Shipway, S.: CalcTool, available at: (last access: 30 May 2018), 2008. Staszak, T., Strelnikov, B., Latteck, R., Renkwitz, T., Friedrich, M., Baumgarten, G., and Lübken, F.-J.: Turbulence generated small-scale structures as PMWE formation mechanism: results from rocket campaign, J. Atmos. Sol.-Terr. Phy., submitted, 2021. Sternovsky, Z., Holzworth, R. H., Horányi, M., and Robertson, S.: Potential distribution around sounding rockets in mesospheric layers with charged aerosol particles, Geophys. Res. Lett., 31, L22101, 10.1029/2004GL020949, 2004. Strelnikov, B., Szewczyk, A., and Rapp, M.: In Situ Measurements of Small-Scale Structures in Neutrals and Charged Aerosols, in: Aeronomy of the Earth's Atmosphere and Ionosphere, Springer, the Netherlands, 83–91, 10.1007/978-94-007-0326-1, 2012. Strelnikov, B., Staszak, T., Latteck, R., Renkwitz, T., Strelnikova, I., Lübken, F.-J., Baumgarten, G., Chau, J. L., Stude, J., Rapp, M., Hörner, I., Löhle, S., Eberhart, M., Fasoulas, S., Friedrich, M., Gumbel, J., Hedin, J., Hörschgen-Eggers, M., Giono, G., and Belova, E.: Sounding rocket project PMWE for investigation of polar mesosphere winter echoes, J. Atmos. Sol.-Terr. Phy., submitted , 2021. Strelnikova, I., Rapp, M., Raizada, S., and Sulzer, M.: Meteor smoke particle properties derived from Arecibo incoherent scatter radar observations, Geophys. Res. Lett., 34, L15815, 10.1029/2007GL030635, 2007. Stude, J.: FLIGHT: 180413A (ROMARA_PMWE1F_HDB), available at:, last access: 16 November 2020. Thrane, E. V.: Middle Atmosphere Program, ICSU Scientific Committee on Solar-Terrestrial Physics, vol. 19, chap. 6, available at: Atmosphere Program vol 019 thrane&pg=PP6#v=onepage&q=Middle Atmosphere Program vol 19 thrane&f=false (last access: 2 February 2020), 138–154, 1986. Voigt, C., Schlager, H., Luo, B. P., Dörnbrack, A., Roiger, A., Stock, P., Curtius, J., Vössing, H., Borrmann, S., Davies, S., Konopka, P., Schiller, C., Shur, G., and Peter, T.: Nitric Acid Trihydrate (NAT) formation at low NAT supersaturation in Polar Stratospheric Clouds (PSCs), Atmos. Chem. Phys., 5, 1371–1380, 10.5194/acp-5-1371-2005, 2005.
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I know how to do a heat distortion effect in compositing.
What I am looking for is a way to do the same effect with a material set up in cycles.
What would be the best way to create a procedural material that can be placed in front of any object and make it look like heat is rising in front of it (without compositing)?
Any ideas would be greatly appreciated.
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$\begingroup$ I've never done it before but I remembered a tutorial from Andrew Price. It's from 2010, so it might be a little outdated in terms of Blender's UI but it still covers the nuts and bolts. blenderguru.com/tutorials/how-to-create-heat-distortion $\endgroup$ Aug 2 '16 at 22:18
• $\begingroup$ Hi icYou. This is an interesting question and it's definitely possible as a material. The trick is to add a plane between the objects and the camera and to either vary the IOR or the Normal based on a noise texture. This answer blender.stackexchange.com/a/19298/29586 does get most of the way there but it doesn't allow for changing angles between the camera, object, and plane. I think I've got a solution using the Incoming geometry node output into the Refraction shader normal (so the rays are always treated as perpendicular) with variation based on a noise texture. $\endgroup$ Oct 14 '16 at 23:00
While it's not possible to vary the refraction throughout an object using volumetrics we can mimic the effect by varying the refraction at points on a surface and view the scene through that surface.
The Refraction shader affects the ray at the point of hitting the surface. If the ray hits the front of the surface then it is treated as a transition from air (IOR = 1.0) into the material, while if it hits the back of a surface then it is calculated as exiting the material back into air. Normally the ray would travel through the mesh, entering through one surface (bending one way) and exiting through another (bending the other way), resulting in the material acting like a prism. However, if we use a plane rather than a manifold mesh then only one side of the refraction effect takes place and we can use this to redirect the ray - as if it had passed through a lower density patch of air.
Refraction is dependent on the angle the ray hits the surface - with zero refraction if it's incident along the Normal and increasing refraction as the angle with the normal increases. We can use the 'Incident' Light Path property to determine the angle of the incoming ray and use this to manipulate the Normal of the surface to get the desired bending of the ray.
To achieve the effect, create a plane and add a new material to it. Open the node editor, remove the default Diffuse shader and replace it with a Refraction shader. Add a Geometry node and link the Incoming node with the Refraction shader Normal. This will mean that the Normal at any point in the shader will always be the same angle as the incident ray and will result in the surface behaving simply as if it were a Transparent shader (as all rays will hit it along the Normal and so no refraction will take place).
Add a Bump node between the Geometry node and the Refraction Shader to affect the distortion and feed this with your heat map as a series of images. Placing the plane between the camera and your scene will now distort the view to simulate heat haze distortion.
distort nodes
Note the addition of a Transparent shader mixed in for Shadow rays to prevent the distortion plane from casting a shadow. Also, ensure the Refraction shader colour is set to pure white.
For the heat map you can either use a Blender smoke simulation saved to a sequence of images or generate simulated smoke using a procedural texture. I used the following crudely generated heat map. This was generated using a Musgrave texture (and some noise), warped so as to taper towards the top, and masked off at the sides. It was animated by simply keyframing the Z-coordinate for the vector of the texture nodes.
heat map
This produced the following result :
heat haze
See the attached blend files for details.
Heat Haze
Heat Map
• $\begingroup$ WOW Rich! great job. That works perfect! much better than what I came up with. Thank you for going into so much detail about it. I will make sure I mark this as answered. $\endgroup$
– icYou520
Oct 16 '16 at 16:29
• $\begingroup$ You're very welcome - glad I could help. $\endgroup$ Oct 16 '16 at 20:06
Your Answer
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If one were to give the matter any thought, what Santa and his reindeer accomplish every Christmas Eve is really quite mind-boggling. Figuring (very conservatively) that if Santa must visit a little over 100 million households in his twenty-four-hour trip around the world, this means that he has to make approximately 1,100 stops per second. He and the reindeer, therefore, must travel nearly 700 miles per second (which is 3,500 times the speed of sound) mushroom bag !
Mushroom Growing Kits – Do They Work? - Emergency Squad
And not only must they go this fast, they must pull the sleigh containing Santa and the toys. If you calculate that there are two good children per each of the 100 million-plus
households that celebrate Christmas throughout the world, this means the reindeer must pull (figuring a mere three pounds per child) 600 million pounds; that’s 300,000 tons!
As a veterinarian who’s had special training in emergency reindeer medicine, I’ve discovered over the years that the best way of explaining how these nine special reindeer (not all reindeer have the ability to fly) accomplish their Christmas Eve mission is to start by dismissing all the phony theories that have been bantered around for the last two thousand years.
1.) Sprinkling the reindeer with fairy dust to make them fly can be dismissed offhand because no where in any of the Christmas tradition throughout the world are there any mention of fairies-or their purported ‘fairy dust.’
2.) The rumors of the reindeer being fed ‘magic corn’ can similarly be ignored. Everybody knows that corn-magic or otherwise-doesn’t grow at the North Pole.
3.) A theory that was popular in the drug-induced stupor of the late 1960’s of the reindeer obtaining their ability to fly by the selective eating of yellow snow that had been peed out by human shamans (who were somehow intoxicated on hallucinogenic mushrooms) can be disregarded as well as simple brainless babble.
4.) Popular during the narcissistic body-building craze of the 1980’s was the belief that Santa’s reindeer were being supercharged by the use of anabolic steroids. The logic escapes me on this theory as well, because, even if the drug might make the reindeer physically strong, it doesn’t make them fly!
5.)A theory whereby Santa’s reindeer somehow manage to inflate themselves like hot air balloons should pass (forgive the pun) from human memory forever. Commonly referred to as ‘the gasbag hypothesis,’ the idea does a fairly good job of explaining how the animals could possibly obtain vertical liftoff. It doesn’t, however, provide an explanation for how they’re able to achieve forward motion once they’re airborne. Forget about flatulence propelling the reindeer forward: the passed gas would be lethal to poor old Santa.
6.) A similar hypothesis, often referred to the ‘Pegasus phenomenon,’ states that the reindeer grow wings for one night a year. This theory accounts nicely for how the animals might fly, but according to the engineers who study this stuff, each reindeer would need a wingspan of 32 feet! Where would they find all of the runway space for taking off and landing, especially in the cities?
7.)The most complicated theory put forth by an elite group of highly learned astrophysicists-and probably the least understood by the average person-is the so called ‘Einstein paradigm.’ Or, put more simply, it is the ‘hoped-for theory of everything.’ This mind-boggling hypothesis journeys into the unfathomable realm of the quantum mechanics. And before I delve too deeply into the theory, let me just warn the gentle reader that this is some pretty heavy stuff! Put in a nutshell, the hypothesis proposes that the Christmas reindeer may be using a not-yet-discovered ability to create alterations in Einstein’s space/time continuum. This distortion in the fabric of time could be the driving principle behind what allows the reindeer to be in a thousand places at any instant of time. Putting it even more simply, by their as-of-yet-unknown ability to control universal time, the reindeer are able to make use of a form of quantum teleportation. This would give them the capacity to be in an infinite number of places at any one time. (I told you this was heavy stuff!!!) The theory goes on and on and on, and involves in-depth knowledge of cosmic worm holes, fractal vortex shedding devices (the reindeer antlers), string theories, and nine-dimension universes. Phew!
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Provide a Dynamic Analysis Crawl Script
Dynamic Analysis
To ensure a comprehensive scan of your URL, you can provide Veracode with a crawl script that contains the necessary input for the Dynamic Analysis scan engine to be able to access all areas of the application.
You must record your crawl script using Selenium and save it as an HTML or SIDE (JSON format) file. The file cannot be larger than 5 MB.
To provide a crawl script:
1. On the URL configuration page, in the Crawl Script section, select Use a crawl script to augment the scan of this URL.
2. Click Choose File to navigate to and select your crawl script file.
3. If you want to limit the scan to only what the crawl script dictates, select Scan only what is specified in the crawl script.
4. Click Save.
Dynamic Analysis runs the crawl script during prescan and returns information about any commands that may fail during the URL scan.
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Why do we have lines on the palms of our hands?
You might be one of the majority of people who think that lines on the palm of our hands are there to foretell the future. Or else, you might have simply wondered why they are there when they don’t seem to fulfill any purpose.
The palm lines on our palms are scientifically-regarded as palmar flexion creases. Human hands start to develop them while the baby is still in the womb at around the 12th week of the gestation period. That means all humans already have these creases on their palms once they are born.
While it may seem not it, the primary function of the palmar flexion creases is to aid the skin’s aid in squeezing and stretching. When you clench or open your hand, these palm lines serve as an avenue for the skin fold or bunch up. It’s only along these creases is the hand skin able to do such function. Through that, it is easier for you to curl your hands, make a fist or grab onto different items.
Hands are the strongest and most used external parts of the body. Imagine all the different activities you do and accomplish with your hands as the day starts until it ends. You use to open the door, pick your toothbrush and brush your teeth, get your keys and twist the knob, etc. The list just goes on and on, as there are innumerable things you do through your hands.
With that, the skin that covers the hand must be flexible enough to suit all such complicated actions and positions. As you fold, quench, bend, or sway your hand, the hands’ skin should be able to adjust accordingly. Thanks to the palmar flexion creases, loose skin is not hanging out from our palms and fingers, and we are able to do different functions using our hands.
The majority of the people possess three significant creases across their palms surfaces. However, some individuals only have one. Such condition is called as the single palmar crease or simian crease and is traced to be brought my abnormality in development. It is commonly found on babies diagnosed with fetal alcohol syndrome or down syndrome. However, doctors still need to do further examination and consider different factors before coming up with a diagnosis. Factors such as race and family history usually tell a lot about the number and width of the creases on one’s palms.
While there is a scientific explanation of the presence of palm lines on our hands, many people still believe that the creases can help them know their future. With that, there is still an abundance of fortune tellers across the globe, who read palms, predict people’s future, and earn a reasonable sum of money.
However, today, palmistry or chiromancy is still regarded as a pseudoscientific or superstitious practice. No wonder cause there is not enough empirical evidence to support such predictions. Moreover, various and opposing interpretations can be made by different fortune tellers from different cultures using the same palm lines.
So, if ever you hear someone wondering about the lines on their palm, tell those creases are there to help us fold, squeeze, crunch, or grab items without unduly stretching our hands’ skin. And, they’re not meant to predict the result of a business proposal, an entrance exam, or other significant events in your life.
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Nature-Based Ritual
The creation and giving of offerings is a practice that goes back to ancient human history, as a means of expressing gratitude, receiving blessings, rituals of forgiveness and healing, or for setting a particular intention. Creating offerings as a personal sacred practice not only helps us to stay aligned with our deeper being, but also cultivates joy through noticing the multitude of ways in which we are blessed. Offerings can come in many ways and can be intended for various beings, and are always a wonderful gesture.
I facilitate both individual and group offerings, for various purposes such as birthdays, beginning and ending partnerships, specific intention setting, gratitude mandalas, and group offerings to the land for healing and deepening connection.
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DEV Community
Discussion on: Explain a State Machine Like I'm Five
louy2 profile image
Yufan Lou
Are you hungry? When you are hungry, what do you do? You eat some bread, maybe drink some milk, right? Then are you full? Yes, you are? Good. But you don't feel hungry and full at the same time, right? Yeah. The feelings you have, you feel hungry or full, but not both at the same time, we can call them states. S-t-a-t-e, states. The things you do to change your feelings, like eating or drinking, we can call them transitions. But if you don't eat, you will become hungry again, right? But what are you doing when you are not eating? Does doing nothing also change how you feel? Yes? No, because you are not really doing nothing. Your stomach absorbs the food you eat. So only doing something changes how you feel, right? Doing nothing doesn't change how you feel. We call this only transitions can change the state. See, you are a little state machine! Yes, yes, you are not a machine, you are a child, not a robot. But we want to make robots which work like human, right? So they can help you do the housework, right? We describe how human do housework with this tool called state machine, just like you draw a house with the crayons. This machine can't work yet, like you can't live in your house on the paper. You can? Can you invite me into the house then? No? That's a pity, but don't worry. There are people who can look at your house, and build one on the ground that we can visit together. They are called engineers. There are also people who can look at the state machine, and build a robot that helps you do some housework! They are also called engineers. Do you want to become an engineer? No? What do you want to do? You like cooking? ...
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A simple class for parsing JSON data into a QVariant hierarchy and vice versa.
The qt-json project is a simple collection of functions for parsing and serializing JSON data to and from QVariant hierarchies. NOTE: Qt5 introduced a native JSON object class. If you are targeting Qt5, you should use that instead.
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target A High Performance, Easy to Use, Network Optimized, JSON Library Dart is both a wire-level binary JSON protocol, along with a high performance, and surprisingly high level, C++ API to interact with that JSON. It i
scottcgi MojoJson MojoJson is an extremely simple and super fast JSON parser. The parser supports all standard Json formats and provides simple APIs for visit different types of the Json values. Also the core algorithm can be easily imple
liqiongfan Modern C++ JSON decoding and encoding library, using modern C++11 features
scikit-hep Awkward Array is a library for nested, variable-sized data, including arbitrary-length lists, records, mixed types, and missing data, using NumPy-like idioms.
anilmaurya Ruby wrapper for simdjson (Parsing gigabytes of JSON per second)
Atrix256 Minimal header only C++ library that allows you to define data schemas which then can be read or written in JSON or binary. Nested structures, arrays, and struct inheritance are supported.
ibireme Benchmark JSON library performance in C/C++
ibireme Fast: can read or write gigabytes per second JSON data on modern CPU. Portable: compliant with ANSI C (C89). Standard: compliant with RFC 8259 and ECMA-404 standard. Safe: complete JSON form, number format and UTF-8 validation. Accuracy: can process int64, uint64 and double number accurately.
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Scrap Car Recycling
When a vehicle is no longer repair-able and its roadworthiness has been compromised, it should be properly disposed of in a manner that does not harm the environment. Scrap car recycling provides valuable end of life vehicles (ELVs) to the end, ensuring all reusable and recyclable components are appropriately removed. It can provide for the safe storage of motor vehicles that are no longer required for business or personal purposes, safe storage of parts that are no longer required for manufacturing operations, and helps in the collection of raw materials by means of reuse programs.
Scrap car recycling refers to the process of separating useful metals and other elements from vehicles that can no longer be salvaged. This usually occurs when the vehicle’s engine malfunctions or requires repair. An example is a dilapidated car that needs to be recycled. There are a number of metals and alloys that make up this waste product. Common elements found in scrap car recycling include aluminum, copper, gold, lead, zinc, iron, lead, tin, steel, and mercury. Other elements may also be recovered from scrappage vehicles include asbestos, cadmium, chromium, cadmium, mercury, lead, rubber, silicone, vinyl, rubber, and timber.
Hazardous Scrap Materials
In scrapping, hazardous materials are separated from the nonhazardous materials. Separating the hazardous materials from the nonhazardous materials is done by two processes: primary pollution and secondary pollution. The process of primary pollution involves pouring a heavy fluid, such as Freon, into the container of the scrap vehicle. This mixture is then pumped into the vehicle, mixed with the exhaust fluid, and forced through the exhaust pipes and vents, before being released outside the vehicle.
The secondary process, which is referred to as secondary recycling, involves separating the hazardous materials from the nonhazardous materials during the transportation. This process is done in two different ways. In primary scrap car recycling, the vehicle is placed inside a container, and either a strong vacuum or strong jet of air is used to force air through the container so that all parts, including the wheels and tires, are expelled out of the vehicle. In secondary scrap car recycling, the vehicle is simply placed inside an enclosure, sealed tightly, and the container is pumped with Freon or air-powered water pressure.
In order for the process of Scrap Car Recycling to work efficiently, all scrap car recyclers must adhere to certain guidelines. These guidelines can range from the most general, meaning everything needed, to the specific, such as specific fluids. There are certain fluids that are only suitable for Scrap Car Recycling and those fluids include antifreeze, anti-freeze, brake fluid, cleaning fluids, fuel, hydraulic fluid, transmission fluid, paint, polymers and metals, thermometers, and plastic. It is also not advisable to mix up these types of fluids because it is difficult to regulate the mixing.
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Saktyavesa-avataras - glorious personalities
From Vanipedia
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Glorious Personality
Srila Prabhupada's books, lectures, conversations and letters reveal the qualities of this glorious personality as seen in the Vaniquotes Saktyavesa-avataras category. An introduction from his teachings is given below in the following 8 quotes.
Quotes from Srila Prabhupada's teachings
Saktyavesa-avataras - explore more within this category.
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20th c American Cubist Painting
Stuart DAVIS (America, 1894 - 1964)
20th c
United States.
San Francisco. San Francisco Museum of Modern Art.
Caption: DAVIS Stuart | Deuce. | 1954 | American | Cubist
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Your current search criteria is: Keyword is "TGC:TJC" and [Object]Creator Display Name is "Stuart DAVIS (1894 - 1964)".
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Utilitarianism: The Four Types Of Ethical Theories
1596 Words 7 Pages
Ethics are moral principles that govern a person 's or group 's behavior and a way someone decides on what is moral, is by using an ethical theory. Ethical theories are not only a set of perspectives for right and wrong, but they also provide a way for someone to seek guidance or to make decisions. However, each theory focuses on different factors such as happiness, duty, or virtue. Their differences are not in the way of decision-making, but in the way, they are applied to achieve a goal. This means that the outcomes could be different, the processes could be different, or even that if the processes are different then the outcomes would be the same. With this is mind, Utilitarianism is an ethical theory based on predicting the outcome of any decision. To the utilitarian, an act is the most ethical if and only if it results in the greatest amount of happiness for the most people. This ethical theory states that everyone’s happiness is weighed in the same. Its focal points are in fairness and a making just decisions. Important to realize, utilitarianism even takes into account a person’s feelings or social constraints. Yet, if those conflicts interfere with the greatest amount of happiness then a utilitarian would basically tell you to get over it. An example of this would be if there …show more content…
The point of them is to provide us with reasoning and the guidance to make our own decisions. There is no one true ethical way to live because that is for the individual to decide. Whether he or she decides to live by sacrificing his or her values for the greater good or by staying true to his or her value for decision making is up to him or her. This being said, the best theory is the theory that feels right for the person. Each person has a set of morals, motivation, and ethics that they value. It is important to realize a course of action is ultimately only up to us. Any method is the right method if we achieve our set
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Readers ask: What Is Logic Gates In Discrete Mathematics?
What are logic gates explain?
Advertisements. Logic gates are the basic building blocks of any digital system. It is an electronic circuit having one or more than one input and only one output. The relationship between the input and the output is based on a certain logic. Based on this, logic gates are named as AND gate, OR gate, NOT gate etc.
What is logic gate and its types?
The basic logic gates are classified into seven types: AND gate, OR gate, XOR gate, NAND gate, NOR gate, XNOR gate, and NOT gate. The truth table is used to show the logic gate function. All the logic gates have two inputs except the NOT gate, which has only one input.
Where are logic gates used?
Computers use logic gates to transform the 1s and 0s from input wires. A logic gate accepts inputs and then outputs a result based on their state.
What is a logic gate and how does it work?
When a transistor is on, or open, then an electric current can flow through. And when it’s off, then no current flows. When you string a bunch of these transistors together, then you get what’s called a logic gate, which lets you add, subtract, multiply, and divide binary numbers in any way imaginable.
You might be interested: Often asked: How Can We Use Mathematics In Our Daily Life?
Who invented logic gates?
Walther Bothe, inventor of the coincidence circuit, got part of the 1954 Nobel Prize in physics, for the first modern electronic AND gate in 1924. Konrad Zuse designed and built electromechanical logic gates for his computer Z1 (from 1935–38).
How do you explain Boolean logic?
Boolean Logic is a form of algebra which is centered around three simple words known as Boolean Operators: “Or,” “And,” and “Not”. At the heart of Boolean Logic is the idea that all values are either true or false.
What are basic logic elements?
All digital systems can be constructed by only three basic logic gates. These basic gates are called the AND gate, the OR gate, and the NOT gate. Some textbooks also include the NAND gate, the NOR gate and the EOR gate as the members of the family of basic logic gates.
Which are the universal logic gates?
A universal gate is a gate which can implement any Boolean function without need to use any other gate type. The NAND and NOR gates are universal gates. In practice, this is advantageous since NAND and NOR gates are economical and easier to fabricate and are the basic gates used in all IC digital logic families.
What is a logic diagram?
logic diagram (plural logic diagrams ) A diagram in the field of logic. Any non-spatial, abstract diagram. Any schematic display of the logical relationships of project activities. A graphical representation of a program using formal logic.
What is SOP and POS?
The SOP (Sum of Product) and POS (Product of Sum) are the methods for deducing a particular logic function. In other words, these are the ways to represent the deduced reduced logic function. Conversely, POS produces a logical expression comprised of the AND of the multiple OR terms.
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What is truth table in logic gates?
The table used to represent the boolean expression of a logic gate function is commonly called a Truth Table. A logic gate truth table shows each possible input combination to the gate or circuit with the resultant output depending upon the combination of these input(s).
How are logic gates made?
“A logic gate in a microchip is made up of a specific arrangement of transistors. For modern microchips, the transistors are of the kind called Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET), and the semiconductor used is silicon.
How do truth tables work?
A truth table is a way of organizing information to list out all possible scenarios. We title the first column p for proposition. In the second column we apply the operator to p, in this case it’s ~p (read: not p). So as you can see if our premise begins as True and we negate it, we obtain False, and vice versa.
What is the easiest way to learn logic gates?
Combinational circuits are built of five basic logic gates:
1. AND gate – output is 1 if BOTH inputs are 1.
2. OR gate – output is 1 if AT LEAST one input is 1.
3. XOR gate – output is 1 if ONLY one input is 1.
4. NAND gate – output is 1 if AT LEAST one input is 0.
5. NOR gate – output is 1 if BOTH inputs are 0.
Why logic gate is so called?
Logic gates are devices that implement Boolean functions, i.e. it does a logic operation on one or more bits of input and gives a bit as an output. The relationship between the input and output is based on a certain logic. Hence logic gates are named as AND gate, OR gate, NOT gate, etc.
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ssc science papers
“Teachers are given a model answer paper using which they evaluate answer sheets. There is no such thing as a ‘strict evaluation’. Rules for evaluation are all given in writing.”(Mujeeb Faruqui/HT Photo)
SSC Science papers: Minor mistakes to cost students major marks
Hindustan Times, Mumbai | By Ankita Bhatkhande, Mumbai
PUBLISHED ON MAR 19, 2019 11:39 AM IST
While answering a question on periodic table, students who write ‘methane’ or ‘ethane’ instead of ‘methyl alcohol’ and ‘ethyl alcohol’ will not get marks.
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TY - JOUR T1 - Specialized Membrane Domains for Water Transport in Glial Cells: High-Resolution Immunogold Cytochemistry of Aquaporin-4 in Rat Brain JF - The Journal of Neuroscience JO - J. Neurosci. SP - 171 LP - 180 DO - 10.1523/JNEUROSCI.17-01-00171.1997 VL - 17 IS - 1 AU - Nielsen, Søren AU - Arnulf Nagelhus, Erlend AU - Amiry-Moghaddam, Mahmood AU - Bourque, Charles AU - Agre, Peter AU - Petter Ottersen, Ole Y1 - 1997/01/01 UR - http://www.jneurosci.org/content/17/1/171.abstract N2 - Membrane water transport is critically involved in brain volume homeostasis and in the pathogenesis of brain edema. The cDNA encoding aquaporin-4 (AQP4) water channel protein was recently isolated from rat brain. We used immunocytochemistry and high-resolution immunogold electron microscopy to identify the cells and membrane domains that mediate water flux through AQP4. The AQP4 protein is abundant in glial cells bordering the subarachnoidal space, ventricles, and blood vessels. AQP4 is also abundant in osmosensory areas, including the supraoptic nucleus and subfornical organ. Immunogold analysis demonstrated that AQP4 is restricted to glial membranes and to subpopulations of ependymal cells. AQP4 is particularly strongly expressed in glial membranes that are in direct contact with capillaries and pia. The highly polarized AQP4 expression indicates that these cells are equipped with specific membrane domains that are specialized for water transport, thereby mediating the flow of water between glial cells and the cavities filled with CSF and the intravascular space. ER -
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Anti-Smoking Letter Writing Campaign
This Anti-Smoking Letter Writing Campaign lesson plan also includes:
Why shouldn't you smoke? Emerging learners of all ages research facts about smoking and its impact on our health. They write a persuasive and friendly letter encouraging a friend not to smoke. This is especially interesting for older grades to complete, as the opportunity to smoke will arise more for this population.
15 Views 139 Downloads
Classroom Considerations
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The interplay between inflammatory bowel disease and Clostridioides difficile co-occurrence and the pediatric gastrointestinal microbiome
Gastrointestinal (GI) infection caused by the bacterium Clostridioides difficile is a common complication of inflammatory bowel disease (IBD), a condition caused by an aberrant host immune response to the GI microbiota. C. difficile infection (CDI) typically occurs after disruption of the GI microbiota, making the immune response to microbiota during IBD a major risk factor. This is particularly important in pediatric populations where 47% may suffer from an IBD-CDI co-occurrence. Fecal microbiota transplant (FMT) is a successful experimental treatment for IBD and CDI. It is thought to work by restoring a healthy-functioning microbiome to the IBD-CDI patient, however the specific host and bacterial factors that define FMT’s success remains unknown. We will recruit pediatric IBD-CDI patients to define host immune responses to FMT treatment. Using a novel IBD-CDI mouse model, we will then attribute host responses to FMT therapy and microbiota composition. This translational research will advance our mechanistic knowledge of FMT efficacy and ultimately impact FMT safety and governance. We will present our findings at international conferences including Canadian Digestive Diseases Week and aim to publish them in high-impact journals.
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In figure AB is a potentiometer wire of length 10 m and resistance . With key K open, the balancing length is 5.5 m. However on closing key K the balancing length reduces to 5 m. The internal resistance of the cell is. answer is 0.1ohm but i think wouldn't the current be zero in both cases through the cell
Asked by advait2163 | 11th Feb, 2012, 08:54: PM
Expert Answer:
Internal resistance, r= [(l1 -l2)/l2]R
r= [(5.5-5.0)/5]x1
r= 0.5/5 =0.1 ohm
when the balanced point is obtained on the potentiometer wire, no current flows in the galvanometer circuit because the fall of potential across the potentiometer wire between zero end and balance point position becomes just equal to the e.m.f of the cell, whereas the current in the potentiometer wire continues flowing.
Answered by | 13th Feb, 2012, 12:00: AM
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Filtration material properties
Generally, the filtration material used for air filters manufacturing is the filtering paper based on cellulose fibers impregnated with phenolic, epoxy or acrylic resins. The impregnation of cellulose fibres protects it from water, oil and fuel fumes. For modern materials, additions of synthetic fibres which increase filtrating efficiency and contaminants absorption are often used. Also completely synthetic filtration materials - unwoven fabrics are made, which due to its specific structure are able to trap several times more contaminants than traditional filtering paper and maintain high efficiency and low flow resistance. Particularly good results are achieved applying two, or even three ply materials, where each layer has a different structure and filtration properties. Air is filtered selectively from various size contaminants flowing through each layer. These features provide absorptivity increase and high filtering efficiency.
The newest UnifluX filters
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Hailing from Denmark, Janine Tuchsen visited Detroit in the Spring of 2013 to meet collaborators and investigate possibility of applying her skills and abilities towards the launching of a community land initiative…
The urban scale
What is the urban scale in a city like Detroit? Where is the public space dedicated to human beings? How can we move and live in a place, which shows us every second, how unimportant and unwanted we are - if we aren´t driving a car? Why do we stay? How can we survive in a place like that? How can we feel content and safe?
And although Detroit is dominated by unused land and abandoned places all over the public landscape, especially these deserted parts of the city have an extraordinary, interesting potential to develop new urban concepts in collaboration with the residents.
The discussion, we had this spring, was dealing with exploring and improving the public space. Residents in the area were motivated and involved in using their urban surroundings in a more active and engaging way. The development of an informal meeting place, an activity and communication platform in the public space was the project’s focus.
The intention was to act as an inspiration for residents and passers-by. By spreading the idea of a meeting platform, they can create a community life and continue.
The urban scale-strategy for Detroit is currently under development, to be continued in summer 2014…
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MA is the quiet space. The tiny hidden distance in between everything and anything. Between space, time, objects, thoughts, sounds. That voidness and stillness.
MA is the shadow between the light beams on the wooden floor; a silent pause between the words that gives them weight. MA is the other level of interaction between beings, invisible to them. MA is something that can’t be described by words or can be explained in so many, at the same time.
The literal interpretation of MA in Japanese language, culture and traditions is space in-between, nothingness, infinity, vacuum beyond everything. Its essence lays in distance within space or time, a physical distance between objects, or momentum between our experiences and perceptions. But that distance is so subtle that nobody can realize it is there.
In various word combinations and moments of life, MA can be interpreted in countless ways. Eventually, MA can be different for every single being feeling and experiencing it.
The starting point and core of MA project is the notion of developing and creating musical compositions through minimalism, which results in an intense merge of sounds and accentuates that strong space and leeway amid them. You are invited to find your own soundless MA among the notes. To hear and feel it your own way.
MA is the most beautiful sound. Simply because it makes us forget where we are, feel and observe our lives and ever changing surroundings as something so meaningful and fascinating.
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pet 7 pdf
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Cambridge PET 7
1. iHICAMBRIDGE UNIVERSITY PRESS UNIVERSITYofCAMBRIDGE ESOL Examinations Cambridge English PRELIMINARYPRELIMINARY ENGLISH TEST WITH ANSWERS 0Sol liciteu el material annex al taulell de prestec j AUTHENTIC EXAMINATION PAPERS FROMCAMBRIDGE ESOL MM'th2/ % °c UNIVERS3ITAT D’ALACANT Biblioteca iiiiiiiiniiiiiii0500586602 Official preparation material for Cambridge English:Preliminary, also known as Preliminary English Test (PET) 2. £ b / 'fi't'i (£>*«. Cambridge English: Preliminary 7 WITH ANSWERS Officialexamination papers from University ofCambridge ESOL Examinations ffii CAMBRIDGE fei UNIVERSITY PRESS 3. CAMBRIDGE UNIVERSITY PRESS University PrintingHouse, Cambridge CBZ 8BS,United Kingdom Cambridge University Press is part of theUniversity of Cambridge. It furthers the University’s mission by disseminating knowledge in the pursuit of education, learning and research at the highest international levels of excellence. Information on this title: © CambridgeUniversity Press 2012 It is normally necessary for written permission for copying to be obtained in advance from a publisher. The worksheets, role play cards, tests, and tapescripts at the back of this book are designed to be copied and distributedin class. The normal requirements are waived here and it is not necessary to write to Cambridge University Press for permission for an individual teacher to make copies for use withinhis or her own classroom. Only those pages that carry the wording ‘© Cambridge University Press’ may be copied. First published 2012 3rd printing 2013 Printed in the United Kingdom by Short Run Press, Exeter A catalogue recordfor this publication is available from the British Library ISBN 978-1-107-675193 Student’s Book with answers ISBN 978-1-107-635661 Student’s Book without answers ISBN 978-1-107-638884 Audio CD Set ISBN 978-1-107-610484 Self-study Pack CambridgeUniversity Press has no responsibility for the persistence or accuracy of URLs for external or third-party internet websites referred to in thispublication, and does not guarantee that any content on such websites is, or willremain, accurate or appropriate.Information regarding prices, travel timetables, and other factualinformation givenin this work is correct at the time of first printing but Cambridge University Press does not guarantee the accuracy of such information thereafter. U vERSi I'AT LJ I UNIVERSID ,D DE 4. Contents A Guide to Cambridge English: Preliminary 4 Testl 14 Test 2 34 Test 3 54 Test 4 74 Frames for the Speaking test 94 Testl Key 106 Test 2 Key 121 Test 3 Key 136 Test 4 Key 151 Sample answer sheets 166 Acknowledgements 171 Visual material for the Speaking test colour section at centre of book 3 5. A Guide to Cambridge English: Preliminary Cambridge English:Preliminary, also known as the Preliminary English Test (PET), is part of a comprehensive range of exams developed by University of Cambridge ESOL Examinations (Cambridge ESOL). Cambridge English exams have similar characteristics, but are designed for different purposes and different levels of English language ability. Cambndge English: Preliminary is at Level B1 (Threshold) of the Council of Europe’s Common European Framework of Reference for Languages (CEFR). It has also been accredited in the UK as an Entry Level 3 ESOL certificate in the UK’s National Qualifications Framework. Examination Council of Europe Framework Level UK National Qualifications Framework Level Cambridge English: Proficiency Certificate ofProficiency inEnglish (CPE) C2 3 Cambridge English: Advanced Certificate in AdvancedEnglish (CAE) C1 2 Cambridge English: First First Certificate inEnglish (FCE) B2 1 Cambridge English: Preliminary Preliminary English Test (PET) B1 Entry 3 Cambridge English: Key KeyEnglish Test (KET) A2 Entry 2 Cambridge English:Preliminary is accepted by employers, and further education and government departments for business, study and immigration purposes. It is also useful preparation for higher level exams, such as Cambridge English: First, Cambridge English: Advanced and Cambridge English:Proficiency. Cambridge English:Preliminary is ideal for learners who need to use English in a practical everyday way to communicate, e.g. read simple textbooks and articles, write simple personal letters, and deal with most of the situations you might meet when travelling in an English- speaking country. Cambridge English:Preliminary is also available in a version with exam content and topics specifically targeted at the interests and experience of school-aged learners. Cambridge English:Preliminary for Schools, also known as PreliminaryEnglish Test (PET) for Schools), follows exactly the same format and level, and leads to the same certificate as Cambridge English:Preliminary. Topics These are the topics used in the Cambridge English: Preliminary exam: 4 6. A Guide to Cambridge English: Preliminary Relations with other people Services Shopping Social interaction Sport Transport Travel and holidays Weather Work and jobs Hobbies and leisure House and home Language Natural world People Personal feelings, opinions and experiences Personal identification Places and buildings Clothes Daily life Education Entertainment and media Environment Food and drink Free time Health, medicine and exercise Cambridge English: Preliminary content -an overview Test focusTiming ContentNamePaper Assessment of candidates’ ability to understand the meaning of written English at word, phrase, sentence, paragraph and whole text level. Reading: Five parts which test a range of reading skills with a variety of texts, ranging from very short notices to longer continuous texts. Reading/ Writing 1 hour 30 minutes Paper 1 Assessment of candidates’ ability to produce straightforward written English, ranging from producing variations on simple sentences to pieces of continuous text. Writing: Three parts which test a range of writing skills. Assessment of candidates’ ability to understand dialogues and monologues in both informal and neutral settings on a range of everyday topics. Four parts ranging from short exchanges to longer dialogues and monologues. 35 minutes (plus 6 minutes transfer time) ListeningPaper 2 Assessment of candidates’ ability to express themselves in order to carry out functions at Threshold level. To ask and to understand questions and make appropriate responses. To talk freely on matters of personal interest. Four parts: In Part 1, candidates interact with an examiner; In Parts 2 and 4, they interact with another candidate; In Part 3, they have an extended individual long turn. Speaking 10-12 minutes per pair of candidates Paper 3 Paper 1: Reading and Writing Paper format The Reading component contains five parts. The Writing component contains three parts. Number of questions Reading has 35 questions; Writing has seven questions. Sources Authentic and adapted-authentic real world notices; newspapers and magazines; simplified encyclopaedias; brochures and leaflets; websites. 5 7. A Guide to Cambridge English: Preliminary Answering Candidates indicate answers by shading lozenges (Reading), or writing answers (Writing) on an answer sheet. Timing 1 hour 30 minutes. Marks Reading: Each of the 35 questions carries one mark. This is weighted so that this comprises 25% of total marks for the whole examination. Writing: Questions 1-5 carry one mark each. Question 6 is marked out of five; and Question 7/8 is marked out of 20. This gives a total of 30 which is weighted so that it represents 25% of total marks for the whole examination. Preparing for the Reading component To prepare for the Reading component, you should read a variety of authentic texts, for example, newspapers and magazines, non-fiction books, and other sources of factual material, such as leaflets, brochures and websites. It is also a good idea to practise reading (and writing) short communicative messages, including notes, cards and emails. Remember, you won’t always need to understand every word in order to be able to do a task in the exam. Before the examination, think about the time you need to do each part. It is usually approximately 50 minutes on the Reading component and 40 minutes on the Writing component. Reading Task Type and Format Task FocusPart Number of Questions Three-option multiple choice. Five short discrete texts: signs and messages, postcards, notes, emails, labels, etc., plus one example. Reading real-world notices and other short texts for the main message. 1 5 Matching. Five items in the form of descriptions of people to match to eight short adapted-authentic texts. Reading multiple texts for specific information and detailed comprehension. 2 5 True/False. Ten items with an adapted-authentic long text. Processing a factual text. Scanning for specific information while disregarding redundant material. 3 10 Four-option multiple choice. Five items with an adapted-authentic long text. Reading for detailed comprehension: understanding attitude, opinion and writer purpose. Reading for gist, inference and global meaning. 4 5 Four-option multiple-choice cloze. Ten items, plus an integrated example, with an adapted-authentic text drawn from a variety of sources. The text is of a factual or narrative nature. Understanding of vocabulary and grammar in a short text, and understanding the lexico-structural patterns in the text. 5 10 6 8. A Guide to Cambridge English: Preliminary Preparing for the Writing component Parti You have to complete five sentences which will test your grammar. There is an example, showing exactly what the task involves. You should write between one and three words to fill this gap. The second sentence, when complete, must mean the same as the first sentence. It is essential to spell correctly and no marks will be given if a word is misspelled. You will also lose the mark if you produce an answer of more than three words, even if your writing includes the correct answer. Part 2 You have to produce a short communicative message of between 35 and 45 words in length. You are told who you are writing to and why, and you must include three content points. These are clearly laid out with bullet points in the question. To gain top marks, all three points must be in your answer, so it is important to read the question carefully and plan what you will include. Marks will not be deducted for minor errors. Before the exam, you need to practise writing answers of the correct length. Answers that are too short or too long and likely to contain irrelevant information, will probably lose marks. The General Mark Scheme below is used with a Task-specific Mark Scheme (see pages 106, 121,136 and 151). General Mark Scheme for Writing Part 2 Mark Criteria All three parts of the message clearly communicated. Only minor spelling errors or occasional grammatical errors. 5 All three parts of the message communicated. Some non-impeding errors in spelling or grammar, or some awkwardness of expression. 4 All three parts of the message attempted. Expression requires interpretation by the reader and contains impeding errors in spelling and grammar. 3 Two parts of the message clearly communicated. Only minor spelling errors or occasional grammatical errors. Only two parts of the message communicated. Some errors in spelling and grammar. The errors in expression may require patience and interpretation by the reader and impede communication. 2 Only one part of the message communicated.1 Question unattempted, or totally incomprehensible response.0 Part 3 You have a choice of task: either a story or an informal letter. You need to write about 100 words. Make sure you practise enough before the exam. Reading simplified readers in English will give you ideas for story writing. Also writing to a penfriend or e-pal will give you useful practice. 7 9. A Guide to Cambridge English: Preliminary Mark Scheme for Writing Part 3 Examiners look at four aspects of your writing: Content, Communicative Achievement, Organisation, and Language. Content focuses on how well you have fulfilled the task, in other words if you have done what you were asked to do. Communicative Achievement focuses on how appropriate the writing is for the letter or story and whether you have used the appropriate register. Organisation focuses on the way you put the piece of writing together, in other words if it is logical and ordered, and the punctuation is correct. Language focuses on your vocabulary and grammar. This includes the range of language, as well as how accurate it is. For each of the subscales, the examiner gives a maximum of five marks; this gives an overall maximum score of 20 for the Part 3 task. Examiners use the following assessment scale: B1 Content Communicative Achievement Organisation Language All content is relevant to the task. Target reader is fully informed. Uses the conventions of the communicative task to hold the target reader’s attention and communicate straightforward ideas. 5 Text is generally well organised and coherent, using a variety of linking words and cohesive devices. Uses a range of everyday vocabulary appropriately, with occasional inappropriate use of less common lexis. Uses a range of simple and some complex grammatical forms with a good degree of control. Errors do not impede communication. 4 Performance shares features of Bands 3 and5. 3 Minor irrelevances and/ or omissions may be present. Target reader is on the whole informed. Uses the conventions of the communicative task in generally appropriate ways to communicate straightforward ideas. Text is connected and coherent, using basic linking words and a limited number of cohesive devices. Uses everyday vocabulary generally appropriately, while occasionally overusing certain lexis. Uses simple grammatical forms with a good degree of control. While errors are noticeable, meaning can still be determined. 2 Performance shares features of Bands 1and3. Irrelevances and misinterpretation of task may be present. Target reader is minimally informed. 1 Produces text that communicates simple ideas in simple ways. Text is connected using basic, high- frequency linking words. Uses basic vocabulary reasonably appropriately. Uses simple grammatical forms with some degree of control. Errors may impede meaning at times. 8 10. A Guide to Cambridge English: Preliminary Organisation LanguageCommunicative Achievement ContentB1 Performance below Band 1.Content is totally irrelevant. Target reader is not informed. 0 Length of responses Make sure you write the correct amount of words. Responses which are too short may not have an adequate range of language and may not provide all the information that is required. Responses which are too long may contain irrelevant content and have a negative effect on the reader. Varieties of English You are expected to use a particular variety of English with some degree of consistency in areas such as spelling, and not for example switch from using a British spelling of a word to an American spelling of the same word. Writing Number of Questions Task FocusTask Type and FormatPart Control and understanding of Threshold/Cambridge English: Preliminary grammatical structures. Rephrasing and reformulating information. 5Sentence transformations. Five items, plus an integrated example, that are theme-related. Candidates are given sentences and then asked to complete similar sentences using a different structural pattern so that the sentence still has the same meaning. 1 A short piece of writing of 35-45 words focusing on communication of specific messages. 1Short communicative message. Candidates are prompted to write a short message in the form of a postcard, note, email, etc. The prompt takes the form of a rubric to respond to. 2 Writing about 100 words focusing on control and range of language. 1A longer piece of continuous writing. There is a choice of two questions, an informal letter or a story. Candidates are assessed on four aspects of their writing: Content, Communication Achievement, Organisation, and Language. 3 Paper 2: Listening Paper format This paper contains four parts. Number of questions 25 Text types All texts are based on authentic situations. 9 11. A Guide to Cambridge English: Preliminary Answering Candidates indicate answers either by shading lozenges (Parts 1, 2 and 4) or writing answers (Part 3) on an answer sheet. Candidates record their answers on the question paper as they listen. They are then given six minutes at the end of the test to copy these on to the answer sheet. Recording information Each text is heard twice. Recordings will contain a variety of accents corresponding to standard variants of native speaker accents. Timing About 35 minutes, including six minutes to transfer answers. Marks Each question carries one mark. This gives a total of 25 marks, which represents 25% of total marks for the whole examination. Part Task Type and Format Task Focus Number of questions 1 Multiple choice (discrete). Short neutral or informal monologues or dialogues. Seven discrete three-option multiple-choice items with visuals, plus one example. Listening to identify key information from short exchanges. 7 2 Multiple choice. Longer monologue or interview (with one main speaker). Six three-option multiple-choice items. Listening to identify specific information and detailed meaning. 6 Gap-fill. Longer monologue. Six gaps to fill in. Candidates need to write one or more words in each space. 3 Listening to identify, understand and interpret information. 6 4 True/False. Longer informal dialogue. Candidates need to decide whether six statements are correct or incorrect. Listening for detailed meaning, and to identify the attitudes and opinions of the speakers. 6 Preparing for the Listening paper You will hear the instructions for each task on the recording, and see them on the exam paper. In Part 1, there is also an example text and task to show you how to record your answers. In Parts 2, 3 and 4, the instructions are followed by a pause; you should read the questions in that part then. This will help you prepare for the listening. The best preparation for the Listening paper is to listen to authentic spoken English at this level. Having discussions provides a good authentic source of listening practice, as does listening to the teacher. You can also listen to texts to give you practice in understanding different voices and styles of delivery. 10 12. A Guide to Cambridge English: Preliminary Paper 3: Speaking Paper format The standard format is two candidates and two examiners. One of the examiners acts as an interlocutor and the other as an assessor. The interlocutor directs the test, while the assessor takes no part in the interaction. Timing 10-12 minutes per pair of candidates. Marks Candidates are assessed on their performance throughout the test. There are a total of 25 marks in Paper 3, making 25% of the total score for the whole examination. TimingTask FocusTask Type and FormatPart Giving information of a factual, personal kind. The candidates respond to questions about present circumstances, past experiences and future plans. 2-3Each candidate interacts with the interlocutor. The interlocutor asks the candidates questions in turn, using standardised questions. 1 minutes 2-3Using functional language to make and respond to suggestions, discuss alternatives, make recommendations and negotiate agreement. Simulated situation. Candidates interact with each other. Visual stimulus is given to the candidates to aid the discussion task. The interlocutor sets up the activity using a standardised rubric. 2 minutes 3Describing photographs and managing discourse, using appropriate vocabulary, in a longer turn. Extended turn. A colour photograph is given to each candidate in turn and they are asked to talk about it for up to a minute. Both photographs relate to the same topic. 3 minutes 3The candidates talk together about their opinions, likes/dislikes, preferences, experiences, habits, General conversation. Candidates interact with each other. The topic of the conversation develops the theme established in Part 3. The interlocutor sets up the activity using a standardised rubric. 4 minutes etc. Assessment Throughout the Speaking test, examiners listen to what you say and give you marks for how well you speak English, so you must try to speak about the tasks and answer the examiner and your partner’s questions. You are awarded marks by two examiners; the assessor and the interlocutor. The assessor awards marks from the Analytical Assessment scales for the following criteria: Grammar and Vocabulary This refers to how accurately you use grammar and also to the correct use of vocabulary. It also includes how wide a range of grammar and vocabulary you use. 11 13. A Guide to Cambridge English:Preliminary Discourse Management This refers to the length, relevance and coherence of your answers. You should be able to produce sentences which are clear and easy to follow. What you say should be related to the topic and the conversation in general. Pronunciation This refers to the how easy it is to understand what you say. You should be able to say words and sentences that are easy to understand. Interactive Communication This refers to how well you can talk about the task and to your partner and the examiner. You should be able to start the conversation and keep it going, and ask for repetition or clarification if needed. B1 Grammar and Vocabulary Discourse Management Pronunciation Interactive Communication Shows a good degree of control of simple grammatical forms, and attempts some complex grammatical forms. Uses a range of appropriate vocabulary to give and exchange views on familiar topics. Produces extended stretches of language despite some hesitation. Contributions are relevant despite some repetition. Uses a range of cohesive devices. Is intelligible. Intonation is generally appropriate. Sentence and word stress is generally accurately placed. Individual sounds are generally articulated clearly. Initiates and responds appropriately. Maintains and develops the interaction and negotiates towards an outcome with very little support. 5 4 Performance shares features of Bands 3 and 5. Shows a good degree of control of simple grammatical forms. Uses a range of appropriate vocabulary when talking about familiar topics. 3 Produces responses which are extended beyond short phrases, despite hesitation. Contributions are mostly relevant, but there may be some repetition. Uses basic cohesive devices. Is mostly intelligible, and has some control of phonological features at both utterance and word levels. Initiates and responds appropriately. Keeps the interaction going with very little prompting and support. 2 Performance shares features of Bands 1and3. 1 Shows sufficient control of simple grammatical forms. Uses a limited range of appropriate vocabulary to talk about familiar topics. Produces responses which are characterised by short phrases and frequent hesitation. Repeats information or digresses from the topic. Is mostly intelligible, despite limited control of phonological features. Maintains simple exchanges, despite some difficulty. Requires prompting and support. 0 Performance below Band 1. 12 14. A Guide to Cambridge English:Preliminary The examiner asking the questions (the interlocutor) gives marks for how well you do overall using a Global Achievement scale. Global AchievementB1 Handles communication on familiar topics, despite some hesitation. Organises extended discourse but occasionally produces utterances that lack coherence, and some inaccuracies and inappropriate usage occur. 5 Performance shares features of Bands 3 and5.4 Handles communication in everyday situations, despite hesitation. Constructs longer utterances but is not able to use complex language except in well-rehearsed utterances. 3 Performance shares features ofBands 1and3.2 Conveys basic meaning in very familiar everyday situations. Produces utterances which tend to be very short – words or phrases -with frequent hesitation and pauses. 1 Performance below Band 1.0 Further information More information about Cambridge English:Preliminary or any other Cambridge ESOL examination can be obtained from Cambridge ESOL at the address below or from the website at University of Cambridge ESOL Examinations Telephone +44 1223 553997 1 Hills Road Cambridge CB1 2EU United Kingdom Fax: +44 1223 553621 email: ESOLHelpdesk
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Search for information, advice and guidance
Improving wellbeing
Here you can learn about improving your wellbeing
Mindfulness and meditation
It’s easy to get caught up in things. Explore how mindfulness and meditation can help in times of difficulty
Movement and exercise
All adults should do some type of exercise and movement every day. Find out more about what this means and the positive effects it can have on us
Eating healthily
Discover how eating healthily plays an important role in maintaining our physical and mental health
Information about this common sleep disorder and ways to improve your sleep quality
It can sometimes be hard to stay connected with others. Here are some things you can do if you are struggling to stay connected with other people.
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The inBandMetadataTrackDispatchType read-only property of the TextTrack interface returns the text track's in-band metadata dispatch type of the text track represented by the TextTrack object.
An in-band metadata dispatch type is a string extracted from a media resource specifically for in-band metadata tracks. An example of a media resource that might have such tracks is a TV station streaming a broadcast on the web. Text Tracks may be used to include metadata for ad targeting, additional information such as recipe data during a cooking show, or trivia game data during a game show.
The value of this attribute could be used to attach these tracks to dedicated script modules as they are loaded.
let label = TextTrack.label;
A string containing the inBandMetadataTrackDispatchType, or an empty string.
In the following example the value of inBandMetadataTrackDispatchType is printed to the console.
let video = document.querySelector('video');
let track = video.addTextTrack("captions", "Captions", "en");
track.mode = "showing";
No specification found
No specification data found for api.TextTrack.label.
Browser compatibility
BCD tables only load in the browser
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Replacing the RTC battery
To replace the RTC battery, you must locate the failed battery in the controller module, remove it from the holder, and then install the replacement battery in the holder.
2. Locate the RTC battery.
RTC battery
RTC battery housing
3. Gently push the battery away from the holder, rotate it away from the holder, and then lift it out of the holder.
Note: Note the polarity of the battery as you remove it from the holder. The battery is marked with a plus sign and must be positioned in the holder correctly. A plus sign near the holder tells you how the battery should be positioned.
4. Remove the replacement battery from the antistatic shipping bag.
5. Locate the empty battery holder in the controller module.
6. Note the polarity of the RTC battery, and then insert it into the holder by tilting the battery at an angle and pushing down.
7. Visually inspect the battery to make sure that it is completely installed into the holder and that the polarity is correct.
8. Reinstall the controller module cover.
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Lesson 15
Equivalent Exponential Expressions
Let's investigate expressions with variables and exponents.
15.1: Up or Down?
Find the values of \(3^x\) and \(\left(\frac13\right)^x\) for different values of \(x\). What patterns do you notice?
\(x\) \(3^x\) \(\left(\frac13\right)^x\)
15.2: What's the Value?
Evaluate each expression for the given value of \(x\)
1. \(3x^2\) when \(x\) is 10
2. \(3x^2\) when \(x\) is \(\frac19\)
3. \(\frac{x^3}{4}\) when \(x\) is 4
4. \(\frac{x^3}{4}\) when \(x\) is \(\frac12\)
5. \(9+x^7\) when \(x\) is 1
6. \(9+x^7\) when \(x\) is \(\frac12\)
15.3: Exponent Experimentation
Find a solution to each equation in the list. (Numbers in the list may be a solution to more than one equation, and not all numbers in the list will be used.)
1. \(64=x^2\)
2. \(64=x^3\)
3. \(2^x=32\)
4. \(x=\left( \frac25 \right)^3\)
5. \(\frac{16}{9}=x^2\)
6. \(2\boldcdot 2^5=2^x\)
7. \(2x=2^4\)
8. \(4^3=8^x\)
This fractal is called a Sierpinski Tetrahedron. A tetrahedron is a polyhedron that has four faces. (The plural of tetrahedron is tetrahedra.)
The small tetrahedra form four medium-sized tetrahedra: blue, red, yellow, and green. The medium-sized tetrahedra form one large tetrahedron.
A large tetrahedron composed of various colors of smaller tetrahedra.
1. How many small faces does this fractal have? Be sure to include faces you can’t see. Try to find a way to figure this out so that you don’t have to count every face.
2. How many small tetrahedra are in the bottom layer, touching the table?
3. To make an even bigger version of this fractal, you could take four fractals like the one pictured and put them together. Explain where you would attach the fractals to make a bigger tetrahedron.
4. How many small faces would this bigger fractal have? How many small tetrahedra would be in the bottom layer?
5. What other patterns can you find?
In this lesson, we saw expressions that used the letter \(x\) as a variable. We evaluated these expressions for different values of \(x\).
• To evaluate the expression \(2x^3\) when \(x\) is 5, we replace the letter \(x\) with 5 to get \(2 \boldcdot 5^3\). This is equal to \(2 \boldcdot 125\) or just 250. So the value of \(2x^3\) is 250 when \(x\) is 5.
• To evaluate \(\frac{x^2}{8}\) when \(x\) is 4, we replace the letter \(x\) with 4 to get \(\frac{4^2}{8} = \frac{16}{8}\), which equals 2. So \(\frac{x^2}{8}\) has a value of 2 when \(x\) is 4.
We also saw equations with the variable \(x\) and had to decide what value of \(x\) would make the equation true.
• Suppose we have an equation \(10 \boldcdot 3^x = 90\) and a list of possible solutions: \({1, 2, 3, 9, 11}\). The only value of \(x\) that makes the equation true is 2 because \( 10 \boldcdot 3^2 = 10 \boldcdot 3 \boldcdot 3\), which equals 90. So 2 is the solution to the equation.
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Essential Glassware Every Bar Needs
Part 2 'Everything Else'
“Will there be any bartenders up there in Heaven, will the pubs never close?”
- Richard Thompson
Martini Glass
Martini glasses are used for drinks between 3 and 6 ounces that are most often served "up" without ice.
Coup Glass
Coupe glasses are stemmed, and typically defined by their broad, shallow saucer. They're exclusively used for serving “up” drinks.
Margarita Glass
The margarita glass is used primarily for serving margaritas. The double-bowl is a fun and distinctive shape that works particularly well for frozen margaritas.
Champagne Glasses
Snifter Glasses
Snifters are a type of glass made for aged spirits like brandy and whiskey. They have a bowl-like appearance with a short stem, a large bottom, and a narrow mouth.
Mule Glasses
The Moscow mule is popularly served in a copper mug, which takes on the cold temperature of the liquid.
PART 1: 'The Staples'
Essential Glassware Every Bar Needs
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Metamorphic rock
Metamorphic rocks arise from the transformation of existing rock to new types of rock, in a process called metamorphism. The original rock (protolith) is subjected to temperatures greater than 150 to 200 °C (300 to 400 °F) and, often, elevated pressure of 100 megapascals (1,000 bar) or more, causing profound physical or chemical changes. During this process, the rock remains mostly in the solid state, but gradually recrystallizes to a new texture or mineral composition.[1] The protolith may be a sedimentary, igneous, or existing metamorphic rock.
Quartzite, a type of metamorphic rock
A metamorphic rock, deformed during the Variscan orogeny, at Vall de Cardós, Lérida, Spain
Metamorphic rocks make up a large part of the Earth's crust and form 12% of the Earth's land surface.[2] They are classified by their protolith, their chemical and mineral makeup, and their texture. They may be formed simply by being deeply buried beneath the Earth's surface, where they are subject to high temperatures and the great pressure of the rock layers above. They can also form from tectonic processes such as continental collisions, which cause horizontal pressure, friction and distortion. Metamorphic rock can be formed locally when rock is heated by the intrusion of hot molten rock called magma from the Earth's interior. The study of metamorphic rocks (now exposed at the Earth's surface following erosion and uplift) provides information about the temperatures and pressures that occur at great depths within the Earth's crust.
Some examples of metamorphic rocks are gneiss, slate, marble, schist, and quartzite. Slate[3] and quartzite[4] tiles are used in building construction. Marble is also prized for building construction[5] and as a medium for sculpture.[6] On the other hand, schist bedrock can pose a challenge for civil engineering because of its pronounced planes of weakness.[7]
Metamorphic rocks form one of the three great divisions of rock types. They are distinguished from igneous rocks, which form from molten magma, and sedimentary rocks, which form from sediments eroded from existing rock or precipitated chemically from bodies of water.[8]
Metamorphic rocks are formed when existing rock is transformed physically or chemically at elevated temperature, without actually melting to any great degree. The importance of heating in the formation of metamorphic rock was first noted by the pioneering Scottish naturalist, James Hutton, who is often described as the father of modern geology. Hutton wrote in 1795 that some rock beds of the Scottish Highlands had originally been sedimentary rock, but had been transformed by great heat.[9]
Hutton also speculated that pressure was important in metamorphism. This hypothesis was tested by his friend, James Hall, who sealed chalk into a makeshift pressure vessel constructed from a cannon barrel and heated it in an iron foundry furnace. Hall found that this produced a material strongly resembling marble, rather than the usual quicklime produced by heating of chalk in the open air. French geologists subsequently added metasomatism, the circulation of fluids through buried rock, to the list of processes that help bring about metamorphism. However, metamorphism can take place without metasomatism (isochemical metamorphism) or at depths of just a few hundred meters where pressures are relatively low (for example, in contact metamorphism).[9]
Metamorphic processes change the texture or mineral composition of the metamorphosed rock.
Mineralogical changes
Metasomatism can change the bulk composition of a rock. Hot fluids circulating through pore space in the rock can dissolve existing minerals and precipitate new minerals. Dissolved substances are transported out of the rock by the fluids while new substances are brought in by fresh fluids. This can obviously change the mineral makeup of the rock.[10]
However, changes in the mineral composition can take place even when the bulk composition of the rock does not change. This is possible because all minerals are stable only within certain limits of temperature, pressure, and chemical environment. For example, at atmospheric pressure, the mineral kyanite transforms to andalusite at a temperature of about 190 °C (374 °F). Andalusite, in turn, transforms to sillimanite when the temperature reaches about 800 °C (1,470 °F). All three have the identical composition, Al
. Likewise, forsterite is stable over a broad range of pressure and temperature in marble, but is converted to pyroxene at elevated pressure and temperature in more silicate-rich rock containing plagioclase, with which the forsterite reacts chemically.[11]
Many complex high-temperature reactions may take place between minerals without them melting, and each mineral assemblage produced provides us with a clue as to the temperatures and pressures at the time of metamorphism. These reactions are possible because of rapid diffusion of atoms at elevated temperature. Pore fluid between mineral grains can be an important medium through which atoms are exchanged.[10]
Textural changes
The change in the particle size of the rock during the process of metamorphism is called recrystallization. For instance, the small calcite crystals in the sedimentary rock limestone and chalk change into larger crystals in the metamorphic rock marble.[12] In metamorphosed sandstone, recrystallization of the original quartz sand grains results in very compact quartzite, also known as metaquartzite, in which the often larger quartz crystals are interlocked.[13] Both high temperatures and pressures contribute to recrystallization. High temperatures allow the atoms and ions in solid crystals to migrate, thus reorganizing the crystals, while high pressures cause solution of the crystals within the rock at their point of contact.[14]
Metamorphic rock containing staurolite and almandine garnet
Metamorphic rocks are characterized by their distinctive mineral composition and texture.
Metamorphic minerals
Because every mineral is stable only within certain limits, the presence of certain minerals in metamorphic rocks indicates the approximate temperatures and pressures at which the rock underwent metamorphosis. These minerals are known as index minerals. Examples include sillimanite, kyanite, staurolite, andalusite, and some garnet.[15]
Other minerals, such as olivines, pyroxenes, hornblende, micas, feldspars, and quartz, may be found in metamorphic rocks, but are not necessarily the result of the process of metamorphism. These minerals can also form during the crystallization of igneous rocks. They are stable at high temperatures and pressures and may remain chemically unchanged during the metamorphic process.[16]
A mylonite (through a petrographic microscope)
Metamorphic rocks are typically more coarsely crystalline than the protolith from which they formed. Atoms in the interior of a crystal are surrounded by a stable arrangement of neighboring atoms. This is partially missing at the surface of the crystal, producing a surface energy that makes the surface thermodynamically unstable. Recrystallization to coarser crystals reduces the surface area and so minimizes the surface energy.[17]
Although grain coarsening is a common result of metamorphism, rock that is intensely deformed may eliminate strain energy by recrystallizing as a fine-grained rock called mylonite. Certain kinds of rock, such as those rich in quartz, carbonate minerals, or olivine, are particularly prone to form mylonites, while feldspar and garnet are resistant to mylonitization.[18]
Folded foliation in a metamorphic rock from near Geirangerfjord, Norway
Many kinds of metamorphic rocks show a distinctive layering called foliation (derived from the Latin word folia, meaning "leaves"). Foliation develops when a rock is being shortened along one axis during recrystallization. This causes crystals of platy minerals, such as mica and chlorite, to become rotated such that their short axes are parallel to the direction of shortening. This results in a banded, or foliated, rock, with the bands showing the colors of the minerals that formed them. Foliated rock often develops planes of cleavage. Slate is an example of a foliated metamorphic rock, originating from shale, and it typically shows well-developed cleavage that allows slate to be split into thin plates.[19]
The type of foliation that develops depends on the metamorphic grade. For instance, starting with a mudstone, the following sequence develops with increasing temperature: The mudstone is first converted to slate, which is a very fine-grained, foliated metamorphic rock, characteristic of very low grade metamorphism. Slate in turn is converted to phyllite, which is fine-grained and found in areas of low grade metamorphism. Schist is medium to coarse-grained and found in areas of medium grade metamorphism. High-grade metamorphism transforms the rock to gneiss, which is coarse to very coarse-grained.[20]
Rocks that were subjected to uniform pressure from all sides, or those that lack minerals with distinctive growth habits, will not be foliated. Marble lacks platy minerals and is generally not foliated, which allows its use as a material for sculpture and architecture.
Mississippian marble in Big Cottonwood Canyon, Wasatch Mountains, Utah.
Metamorphic rocks are one of the three great divisions of all rock types, and so there is a great variety of metamorphic rock types. In general, if the protolith of a metamorphic rock can be determined, the rock is described by adding the prefix meta- to the protolith rock name. For example, if the protolith is known to be basalt, the rock will be described as a metabasalt. Likewise, a metamorphic rock whose protolith is known to be a conglomerate will be described as a metaconglomerate. For a metamorphic rock to be classified in this manner, the protolith should be identifiable from the characteristics of the metamorphic rock itself, and not inferred from other information.[21][22][23]
Under the British Geological Society classification system, if all that can be determined about the protolith is its general type, such as sedimentary or volcanic, the classification is based on the mineral mode (the volume percentages of different minerals in the rock). Metasedimentary rocks are divided into carbonate-rich rock (metacarbonates or calcsilicate-rocks) or carbonate-poor rocks, and the latter are further classified by the relative abundance of mica in their composition. This ranges from low-mica psammite through semipellite to high-mica pellite. Psammites composed mostly of quartz are classified as quartzite. Metaigneous rocks are classified similarly to igneous rocks, by silica content, from meta-ultramafic-rock (which is very low in silica) to metafelsic-rock (with a high silica content).[22]
Where the mineral mode cannot be determined, as is often the case when rock is first examined in the field, then classification must be based on texture. The textural types are:
• Schists, which are medium-grained strongly foliated rocks.[22] These show the most well-developed schistosity, defined as the extent to which platy minerals are present and are aligned in a single direction, so that the rock easily splits into plates less than a centimeter (0.4 inches) thick.[23]
• Gneisses, which are more coarse grained and show thicker foliation that schists, with layers over 5mm thick.[22] These show less well-developed schistosity.[23]
• Granofels, which show no obvious foliation[22] or schistosity.[23]
A hornfels is a granofels that is known to result from contact metamorphism. A slate is a fine-grained metamorphic rock that easily splits into thin plates but shows no obvious compositional layering. The term is used only when very little else is known about the rock that would allow a more definite classification. Textural classifications may be prefixed to indicate a sedimentary protolith (para-, such as paraschist) or igneous protolith (ortho-, such as orthogneiss). When nothing is known about the protolith, the textural name is used without a prefix. For example, a schist is a rock with schistose texture whose protolith is uncertain.[22]
Special classifications exist for metamorphic rocks with a volcaniclastic protolith or formed along a fault or through hydrothermal circulation. A few special names are used for rocks of unknown protolith but known modal composition, such as marble, eclogite, or amphibolite.[22] Special names may also be applied more generally to rocks dominated by a single mineral, or with a distinctive composition or mode or origin. Special names still in wide use include amphibolite, greenschist, phyllite, marble, serpentinite, eclogite, migmatite, skarn, granulite, mylonite, and slate.[23]
The basic classification can be supplemented by terms describing mineral content or texture. For example, a metabasalt showing weak schistosity might be described as a gneissic metabasalt, and a pellite containing abundant staurolite might be described as a staurolite pellite.[22][23]
Metamorphic facies
T (°C)
graph corresponds to circumstances within the Earth's crust and upper mantle.
A metamorphic facies is a set of distinctive assemblages of minerals that are found in metamorphic rock that formed under a specific combination of pressure and temperature. The particular assemblage is somewhat dependent on the composition of that protolith, so that (for example) the amphibolite facies of a marble will not be identical with the amphibolite facies of a pellite. However, the facies are defined such that metamorphic rock with as broad a range of compositions as is practical can be assigned to a particular facies. The present definition of metamorphic facies is largely based on the work of the Finnish geologist, Pentti Eskola, with refinements based on subsequent experimental work. Eskola drew upon the zonal schemes, based on index minerals, that were pioneered by the British geologist, George Barrow.[24]
The metamorphic facies is not usually considered when classifying metamorphic rock based on protolith, mineral mode, or texture. However, a few metamorphic facies produce rock of such distinctive character that the facies name is used for the rock when more precise classification is not possible. The chief examples are amphibolite and eclogite. The British Geological Survey strongly discourages use of granulite as a classification for rock metamorphosed to the granulite facies. Instead, such rock will often be classified as a granofels.[22] However, this is not universally accepted.[23]
Metamorphic rocks make up a large part of the Earth's crust and form 12% of the Earth's land surface.[2] The lower continental crust is mostly metamafic-rock and pellite which have reached the granulite facies. The middle continental crust is dominated by metamorphic rock that has reached the amphibolite facies.[25] Within the upper crust, which is the only part of the Earth's crust geologists can directly sample, metamorphic rock forms only from processes that can occur at shallow depth. These are contact (thermal) metamorphism, dynamic (cataclastic) metamorphism, hydrothermal metamorphism, and impact metamorphism. These processes are relatively local in occurrence and usually reach only the low-pressure facies, such as the hornfels and sanidinite facies. Most metamorphic rock is formed by regional metamorphism in the middle and lower crust, where the rock reaches the higher-pressure metamorphic facies. This rock is found at the surface only where extensive uplift and erosion has exhumed rock that was formerly much deeper in the crust.[26]
Orogenic belts
Metamorphic rock is extensively exposed in orogenic belts produced by the collision of tectonic plates at convergent boundaries. Here formerly deeply buried rock has been brought to the surface by uplift and erosion.[27] The metamorphic rock exposed in orogenic belts may have been metamorphosed simply by being at great depths below the Earth's surface, subjected to high temperatures and the great pressure caused by the immense weight of the rock layers above. This kind of regional metamorphism is known as burial metamorphism. This tends to produced low-grade metamorphic rock.[28] Much more common is metamorphic rock formed during the collision process itself.[29] The collision of plates causes high temperatures, pressures and deformation in the rocks along these belts.[30] Metamorphic rock formed in these settings tends to shown well-developed schistosity.[29]
Metamorphic rock of orogenic belts shows a variety of metamorphic facies. Where subduction is taking place, the basalt of the subducting slab is metamorphosed to high-pressure metamorphic facies. It initially undergoes low-grade metamorphism to metabasalt of the zeolite and prehnite-pumpellyite facies, but as the basalt subducts to greater depths, it is metamorphosed to the blueschist facies and then the eclogite facies. Metamorphism to the eclogite facies releases a great deal of water vapor from the rock, which drives volcanism in the overlying volcanic arc. Eclogite is also significantly denser than blueschist, which drives further subduction of the slab deep into the Earth's mantle. Metabasalt and blueschist may be preserved in blueschist metamorphic belts formed by collisions between continents. They may also be preserved by obduction onto the overriding plate as part of ophiolites.[31] Eclogites are occasionally found at sites of continental collision, where the subducted rock is rapidly brought back to the surface, before it can be converted to the granulite facies in the hot upper mantle. Many samples of eclogite are xenoliths brought to the surface by volcanic activity.[32]
Many orogenic belts contain higher-temperature, lower-pressure metamorphic belts. These may form through heating of the rock by ascending magmas of volcanic arcs, but on a regional scale. Deformation and crustal thickening in an orogenic belt may also produce these kinds of metamorphic rocks. These rocks reach the greenschist, amphibolite, or granulite facies and are the most common of metamorphic rocks produced by regional metamorphosis. The association of an outer high-pressure, low-temperature metamorphic zone with an inner zone of low-pressure, high-temperature metamorphic rocks is called a paired metamorphic belt. The main islands of Japan show three distinct paired metamorphic belts, corresponding to different episodes of subduction.[33][34]
Metamorphic core complexes
Metamorphic rock is also exposed in metamorphic core complexes, which form in region of crustal extension. They are characterized by low-angle faulting that exposes domes of middle or lower crust metamorphic rock. These were first recognized and studied in the Basin and Range Province of southwestern North America,[35] but are also found in southern Aegean Sea, in the D'Entrecasteaux Islands, and in other areas of extension.[36]
Granite-greenstone belts
Continental shields are regions of exposed ancient rock that make up the stable cores of continents. The rock exposed in the oldest regions of shields, which is of Archean age (over 2500 million years old), mostly belong to granite-greenstone belts. The greenstone belts contain metavolcanic and metasedimentary rock that has undergone a relatively mild grade of metamorphism, at temperatures of 350–500 °C (662–932 °F) and pressures of 200–500 MPa (2,000–5,000 bar). They can be divided into a lower group of metabasalts, including rare metakomatiites; a middle group of meta-intermediate-rock and meta-felsic-rock; and an upper group of metasedimentary rock.[37]
The greenstone belts are surrounded by high-grade gneiss terrains showing highly deformed low-pressure, high-temperature (over 500 °C (932 °F)) metamorphism to the amphibolite or granulite facies. These form most of the exposed rock in Archean cratons.[37]
The granite-greenstone belts are intruded by a distinctive group of granitic rocks called the tonalite-trondhjemite-granodiorite or TTG suite. These are the most voluminous rocks in the craton and may represent an important early phase in the formation of continental crust.[37]
Mid-ocean ridges
Mid-ocean ridges are where new oceanic crust is formed as tectonic plates move apart. Hydrothermal metamorphism is extensive here. This is characterized by metasomatism by hot fluids circulating through the rock. This produces metamorphic rock of the greenschist facies. The metamorphic rock, serpentinite, is particularly characteristic of these settings, and represents chemical transformation of olivine and pyroxene in ultramafic rock to serpentine group minerals.[38] [29]
Contact aureoles
A contact metamorphic rock made of interlayered calcite and serpentine from the Precambrian of Canada. Once thought to be a pseudofossil called Eozoön canadense. Scale in mm.
Contact metamorphism takes place when magma is injected into the surrounding solid rock (country rock).[39] The changes that occur are greatest wherever the magma comes into contact with the rock because the temperatures are highest at this boundary and decrease with distance from it. Around the igneous rock that forms from the cooling magma is a metamorphosed zone called a contact aureole. Aureoles may show all degrees of metamorphism from the contact area to unmetamorphosed (unchanged) country rock some distance away. The formation of important ore minerals may occur by the process of metasomatism at or near the contact zone.[40] Contact aureoles around large plutons may be as much as several kilometers wide.[41]
The term hornfels is often used by geologists to signify those fine grained, compact, non-foliated products of contact metamorphism.[42] The contact aureole typically shows little deformation, and so hornfels is usually devoid of schistosity and forms a tough, equigranular rock. If the rock was originally banded or foliated (as, for example, a laminated sandstone or a foliated calc-schist) this character may not be obliterated, and a banded hornfels is the product.[42] Contact metamorphism close to the surface produces distinctive low-pressure metamorphic minerals,[39] such as spinel, andalusite, vesuvianite, or wollastonite.[43]
Similar changes may be induced in shales by the burning of coal seams.[42] This produces a rock type named clinker.[44]
There is also a tendency for metasomatism between the igneous magma and sedimentary country rock, whereby the chemicals in each are exchanged or introduced into the other. In that case, hybrid rocks called skarn arise.[42][45]
Other occurrences
Dyamic (cataclastic) metamorphism takes place locally along faults. Here intense shearing of the rock typically forms mylonites. [29]
Impact metamorphism is unlike other forms of metamorphism in that it takes place during impact events by extraterrestrial bodies. It produces rare ultrahigh pressure metamorphic minerals, such as coesite and stishovite.[46] Coesite is rarely found in eclogite brought to the surface in kimberlite pipes, but the presence of stishovite is unique to impact structures.[47]
Slate tiles are used in construction, particularly as roof shingle.[3]
Quartzite is sufficiently hard and dense that it is difficult to quarry. However, some quartzite is used as dimension stone, often as slabs for flooring, walls, or stair steps. About 6% of crushed stone, used mostly for road aggregate, is quartzite.[4]
Marble is also prized for building construction[48] and as a medium for sculpture.[6]
Schistose bedrock can pose a challenge for civil engineering because of its pronounced planes of weakness.[7] A hazard may exist even in undisturbed terrain. On August 17, 1959, a magnitude 7.2 earthquake destabilized a mountain slope near Hebgen Lake, Montana, composed of schist. This caused a massive landslide that killed 26 people camping in the area.[49]
Metamorphosed ultramafic rock contains serpentine group minerals, which includes varieties of asbestos that pose a hazard to human health.[50]
See also
• Blueschist
• List of rock types
• List of rock textures
• Metavolcanic rock
• Neomorphism
• Subduction zone metamorphism
2. Wilkinson, Bruce H.; McElroy, Brandon J.; Kesler, Stephen E.; Peters, Shanan E.; Rothman, Edward D. (2008). "Global geologic maps are tectonic speedometers – Rates of rock cycling from area-age frequencies". Geological Society of America Bulletin. 121 (5–6): 760–79. doi:10.1130/B26457.1.
3. Schunck, Eberhard; Oster, Hans Jochen (2003). Roof Construction Manual : Pitched Roofs (2003 ed.). München: DE GRUYTER. ISBN 9783034615631.
5. "Marble" (PDF). Glossary of Terms. Marble Institute of America. p. 23-15. Retrieved 28 February 2021.
7. Zhang, Xiao-Ping; Wong, Louis Ngai Yuen; Wang, Si-Jing; Han, Geng-You (August 2011). "Engineering properties of quartz mica schist". Engineering Geology. 121 (3–4): 135–149. doi:10.1016/j.enggeo.2011.04.020.
9. Yardley 1989, pp. 1-5.
10. Yardley 1989, p. 5.
11. Yardley 1989, pp. 32-33, 110, 130-131.
12. Yardley 1989, p. 127, 154.
13. Jackson, Julia A., ed. (1997). "Metaquartzite". Glossary of geology (Fourth ed.). Alexandria, Virginia: American Geological Institute. ISBN 0922152349.
14. Yardley 1989, p. 154-158.
15. Yardley 1989, pp. 8-10.
16. Klein, Cornelis; Hurlbut, Cornelius S., Jr. (1993). Manual of mineralogy : (after James D. Dana) (21st ed.). New York: Wiley. pp. 449, 480, 483, 497, 516, 518, 529, 539, 543. ISBN 047157452X.
17. Yardley 1989, p. 148-158.
18. Yardley 1989, p. 158.
19. Yardley 1989, p. 22, 168-170.
20. Wicander R. & Munroe J. (2005). Essentials of Geology. Cengage Learning. pp. 174–77. ISBN 978-0495013655.
21. Yardley 1989, pp. 21-27.
22. Robertson, S. (1999). "BGS Rock Classification Scheme, Volume 2: Classification of metamorphic rocks" (PDF). British Geological Survey Research Report. RR 99-02. Retrieved 27 February 2021.
23. Schmid, R.; Fettes, D.; Harte, B.; Davis, E.; Desmons, J. (2007). "How to name a metamorphic rock.". Metamorphic Rocks: A Classification and Glossary of Terms: Recommendations of the International Union of Geological Sciences Subcommission on the Systematics of Metamorphic Rocks (PDF). Cambridge: Cambridge University Press. pp. 3–15. Retrieved 28 February 2021.
24. Yardley 1989, pp. 49-51.
25. Rudnick, Roberta L.; Fountain, David M. (1995). "Nature and composition of the continental crust: A lower crustal perspective". Reviews of Geophysics. 33 (3): 267. Bibcode:1995RvGeo..33..267R. doi:10.1029/95RG01302.
26. Yardley 1989, pp. 12-13.
27. Levin 2010, pp. 76-77, 82-83.
28. Robinson, D.; Bevins, R. E.; Aguirre, L.; Vergara, M. (1 January 2004). "A reappraisal of episodic burial metamorphism in the Andes of central Chile". Contributions to Mineralogy and Petrology. 146 (4): 513–528. Bibcode:2004CoMP..146..513R. doi:10.1007/s00410-003-0516-4. S2CID 140567746.
29. Yardley 1989, p. 12.
30. Kearey, P.; Klepeis, Keith A.; Vine, Frederick J. (2009). Global tectonics (3rd ed.). Oxford: Wiley-Blackwell. pp. 275–279. ISBN 9781405107778.
31. Kearey, Klepeis & Vine 2009, pp. 275-279.
32. Kearey, Klepeis & Vine 2009, pp. 367-368.
33. Miyashiro, Akiho (1973). Metamorphism and Metamorphic Belts. Dordrecht: Springer Netherlands. ISBN 9789401168366.
34. Kearey, Klepeis & Vine 2009, pp. 368-369.
35. Crittenden, M.D.; Coney, P.J.; Davis, G.H.; Davis, G.H., eds. (1980). Cordilleran metamorphic core complexes (Memoir 153). Geological Society of America. ISBN 978-0813711539.
36. Kearey, Klepeis & Vine 2009, p. 169.
37. Kearey, Klepeis & Vine 2009, p. 350.
38. Kearey, Klepeis & Vine 2009, pp. 28-29, 129-131.
39. Yardley 1998, p. 12.
40. Marshak, Stephen (2009). Essentials of Geology (3rd ed.). W. W. Norton & Company. ISBN 978-0393196566.
42. One or more of the preceding sentences incorporates text from a publication now in the public domain: Flett, John Smith (1911). "Petrology". In Chisholm, Hugh (ed.). Encyclopædia Britannica. 21 (11th ed.). Cambridge University Press. p. 332–33.
43. Klein & Hurlbut 1993, pp. 385, 456, 466, 485.
44. Milligan, Mark (September 2007). "Geosights: Colorful coal "clinker" close to Castle Gate, Carbon County". Survey Notes. 39 (3). Retrieved 28 February 2021.
45. Yardley 1989, p. 126.
46. Yardley 1989, p. 13.
47. Liu, Liang; Zhang, Junfeng; Green, Harry W.; Jin, Zhenmin; Bozhilov, Krassmir N. (November 2007). "Evidence of former stishovite in metamorphosed sediments, implying subduction to >350 km". Earth and Planetary Science Letters. 263 (3–4): 181. Bibcode:2007E&PSL.263..180L. doi:10.1016/j.epsl.2007.08.010.
49. "The Hebgen Lake, Montana, earthquake of August 17, 1959". U.S. Geological Survey Professional Paper. Professional Paper. 435. 1964. doi:10.3133/pp435.
50. Klein & Hurlbut 1993, pp. 507-511.
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Estudio Persona
Puru Side Table
Designed by Estudio Persona, 2018
$ 2,500.00
The concept of the beauty of simplicity was the inspiration behind the Puru side table. Two elements are expressed by two materials, wood and stainless steel. Deriving it's name from the Japanese word for pool, the waxed white oak against the polished stainless steel produce a mirroring effect. In the Puru, each element is reminding it's need for each other in the reflection.
Bleached Maple veneer, black stained Maple
H: 18'' x W:12'' x D: 21''
H: 45.72 cm x W: 30.48 cm x D: 53.34 cm
Lead Time: 10-12 weeks
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@article {5591, title = {Starved Escherichia coli preserve reducing power under nitric oxide stress.}, journal = {Biochem Biophys Res Commun}, volume = {476}, year = {2016}, month = {2016 07 15}, pages = {29-34}, abstract = {
Nitric oxide (NO) detoxification enzymes, such as NO dioxygenase (NOD) and NO reductase (NOR), are important to the virulence of numerous bacteria. Pathogens use these defense systems to ward off immune-generated NO, and they do so in environments that contain additional stressors, such as reactive oxygen species, nutrient deprivation, and acid stress. NOD and NOR both use reducing equivalents to metabolically deactivate NO, which suggests that nutrient deprivation could negatively impact their functionality. To explore the relationship between NO detoxification and nutrient deprivation, we examined the ability of Escherichia coli to detoxify NO under different levels of carbon source availability in aerobic cultures. We observed failure of NO detoxification under both carbon source limitation and starvation, and those failures could have arisen from inabilities to synthesize Hmp (NOD of E.~coli) and/or supply it with sufficient NADH (preferred electron donor). We found that when limited quantities of carbon source were provided, NO detoxification failed due to insufficient NADH, whereas starvation prevented Hmp synthesis, which enabled cells to maintain their NADH levels. This maintenance of NADH levels under starvation was confirmed to be dependent on the absence of Hmp. Intriguingly, these data show that under NO stress, carbon-starved E.~coli are better positioned with regard to reducing power to cope with other stresses than cells that had consumed an exhaustible amount of carbon.
}, keywords = {Carbon, Dihydropteridine Reductase, Escherichia coli, Escherichia coli Proteins, Hemeproteins, NADH, NADPH Oxidoreductases, NADP, Nitric Oxide, Oxidation-Reduction, Oxygenases, Stress, Physiological}, issn = {1090-2104}, doi = {10.1016/j.bbrc.2016.05.082}, author = {Gowers, Glen-Oliver F and Robinson, Jonathan L and Brynildsen, Mark P} }
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Home and Reset Print Mode
Conservatives call the media Mockingbird because of the CIA's operation Mockingbird.
-- Future Scenarios
-- Scenarios
-- Anunnaki
My Other Sites
and Videos
Into to History
Stuff for Stuff - 1949
The Storyline of the above video. - This short begins with a history of economics, starting with the ancient Egyptians and Phoenicians. The narrator stresses that throughout history, free trade among nations has been the engine that drives prosperity and democracy. When protectionist policies are put into effect, everybody suffers. It was these protectionist policies that caused the Great Depression and led to the rise of tyrants after World War I. The film closes by extolling the Marshall Plan, which rebuilt Europe after World War II.
These two videos explain what actually happened, instead of the optimistic ending of the top video.
This information coupled with the Gladio scenario outlines how America got to today unbeknownst to it's citizens
The Petrodollar in a Nutshell
The Curse of Petro dollar
And more.
Help me promote this website!
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Network Leeds
Aire Valley Arts - Unfolding
calendarView calendarallView all events
date Wed, 8 Sep 10:00am - Thu, 28 Oct 4:00pm
authorPhilip Lickley
The exhibition is split between Bradford Cathedral and Kala Sangam. Opening times for the venues may vary depending on events but you can see both parts of the exhibition during the following times:
Monday - Friday: 10am - 4pm
(except Wednesdays: 12noon - 4pm)
Saturday: 10am - 2pm
tagEvent category: Arts
profileAn excellent communication forum
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@article{Nieto Moreno de Diezmas_2016, title={The impact of CLIL on the acquisition of L2 competences and skills in primary education}, volume={16}, url={https://revistas.um.es/ijes/article/view/239611}, DOI={10.6018/ijes/2016/2/239611}, abstractNote={<p>The aim of this paper is to provide new evidence on the effectiveness of Content and Language Integrated Learning (CLIL) in the acquisition of English language competences (reading, writing, listening and spoken production and interaction) compared to traditional learning of English as a foreign language (EFL) in primary school settings. To do so, results of CLIL and non-CLIL learners enrolled in the 4 th year of primary education (9-10-year-olds) were examined and contrasted. Findings showed that the only communicative competence in which differences in favour of CLIL students were significant was spoken production and interaction. However, significant differences have also been detected in the following indicators: “preparing an outline before writing” (writing), “understanding space-time relations” (reading), and “global comprehension” and “identification of details” (listening). The confined effectiveness of CLIL may be due to the limited time of extra exposure to English, the young age of participants and the absence of any selection process for CLIL learners.</p>}, number={2}, journal={International Journal of English Studies}, author={Nieto Moreno de Diezmas, Esther}, year={2016}, month={Dec.}, pages={81–101} }
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| 0.839696 |
What Skills Do You Consider to Be Important as a Leader in the Vpc and Why?
2717 Words11 Pages
I believe there are many skills which are important as a leader in the VPC. Firstly being confident and having good communication skills are key requirements. Being confident is important as being in a leadership position would require you to be able to happily speak to people and 'lead' them. Being good at communicating would be important as you may have to speak to the group about a task or feed them some information. Another thing which is important, similar to being confident in your abilities is being confident in yourself. If you should come across a situation you are not familiar with, or something you possibly struggle with, you need to have the confidence within yourself to be able to do what you have been asked. Another skill required by a VPC would be the skill to understand ethnic diversity. A VPN should be able to treat everyone with equality and also be able to feel empathy. A situation could arise where you could come across someone of another ethnicity and a VPN would be expect to treat them the same and also consider the fact they may not be able to do certain thing when planing/running an activity. Patience would also be another important skill a VPN should have. A VPN would have to be patient if someone didn’t understand something relayed to them and try to explain it again. A VPN should be honest and trustworthy, this would be because they would be relied on by other people and if they were to let them down, others would suffer. A VPN should also have the skill to delegate, if a problem should arise within a task/group, the team leader should quickly and effectively deal with the situation. Finally a VPN must be committed to their role. A VPN should be committed to the cadets and their group. They should put extra effort in to their role to benefit the Group. What relevant experience do you have which you feel will help you in a new leadership
Open Document
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Please note that we will require you
* to wear a mask at all times whilst instore
* sign in and sanitise your hands at entry
* maintain a 2m distance between you and other browsing customers
Creative Knitting
Creative Knitting
O'Connor, Kaori
Patterns and motifs from all over the world, including traditional English images of hearts and flowers, the intricate tracery of a Turkish kilim and tapestries of eighteenth-century Italy are used as inspiration for these colour knitting designs. There are twenty-seven basic designs each of which can be used to knit up eight different garments, giving a total of over a hundred combinations.;By the same author: "Creative dressing"
Second hand Hardback
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The Elegant Universe
Student Handout
Forces of Nature
The world is made up of elementary particles called quarks, which include the up, down, charm, strange, top, and bottom quarks; and leptons, which include the electron, the muon, the tau, and their corresponding neutrinos. But how do these particles interact? How do they form the world you see around you? Find out in this activity.
1. Look at the "Finding Forces" student handout. The graphic shows four areas of matter (labeled 1, 2, 3, and 4) that are governed by the four fundamental forces of nature.
2. Read "The Four Fundamental Forces" section that starts below. Then see if you can match each force correctly with the numbers on the "Finding Forces" illustration. Write the letter of each description next to the number you think represents the area of matter governed by that force.
3. Once you have labeled the forces, write next to each force the name of the particle that carries (or is believed to carry) that force between the matter particles it governs. The force carrier particles are:
• photon
• gluon
• graviton (theorized)
• W-, W+, Z0
Illustration of the four forces: gravity, strong force, weak force, electromagnetism
The Four Fundamental Forces
Write your answers on a separate piece of paper.
1. Which force is responsible for a neutron decaying into a proton?
2. Which force bonds quarks together into particles like protons and neutrons?
3. Which force governs the motion of an apple falling from a tree?
4. What are you made of? What forces hold you together?
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Solving the Mystery
Scientific Observation: Mystery Tubes
Today students learned that to become a good scientist, you have to make specific and detailed observations so other people will understand what you have found or tested. We introduced the steps of the Scientific Method and learned how to write a great hypothesis, test it, and rework it until their observations matched their hypothesis.
For our activity, students had to make observations about what was happening in a sealed PVC ‘mystery tube’ without being able to see inside. Once they made their observations and wrote a hypothesis to explain what they observed, they worked in groups to build their own working models of the mystery tube. We finished up by talking about why many types of scientists also use models in their studies to help explain a phenomenon.
This lesson was exciting, challenging and great fun to complete.
Many thanks to all the parents who sent in paper tubes for this lesson! If you haven’t returned your child’s photo permission form, please do so this week.
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Open 7 days INFO
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| 0.995156 |
Introduction to Programmable Attenuator
Introduction to Programmable rf attenuator, Working, Features, Uses
Programmable (radio frequency) rf attenuators, is also recognized as voltage measured actuators, these are accessible in 50Ω impedance. voltage measured (controlled) programmable attenuators are obtainable with SMA (Simplified Memory-bounded Algorithm) connector and RF (radio frequency) dB reduction tenets which range from one decibel to 63 B. The frequency range of voltage-controlled attenuators is from one…
What is Venturimeter
Venturimeter: Definition, Parts, Working Principle, Derivation, Applications, Advantages, and Disadvantages
A venturi meter is an instrument which is to calculate the liquid flow in tubes. This meter is works on the principle of Bernoulli’s equation. Inner side of the pipe, pressure variance is produced by dealing the cross-sectional area of the movement passageway. This alteration in pressure is calculated with the assistance of a manometer…
RF Attenuators: basics, types, symbols
RF Attenuators: basics, types, symbols
Hello, friends welcome to the new post. RF attenuators decrease the power of a (radio frequency) RF signal. Characteristically, the RF signal is passed on a coaxes cable and this attenuator is used online with that cable. This attenuator also used in circuit enterprises and microwave submissions. The prerequisite to decrease a (radio frequency) RF…
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| 0.786471 |
Significant advancements in engine design are desired for future vehicles. Yet, two problems persist: efficient combustion and user friendliness. This includes considerations of vibration, vehicle handling, fuel availability, mean piston speed, endurance, engine lubrication, crankshaft torque, and system simplicity and reliability. This disclosure describes an innovative 4 stroke engine that simultaneously provides reliability, efficiency, and low emissions in a single design.
Continue reading
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Send to disconnect examples
For a service like FTP, this would be QUIT/r/n. If a command string is not specified, the connection is closed by sending a FIN packet and then an RST packet.
The /r (carriage return) and /n (line feed) are the conventions for sending these control characters to terminate a string. You can use:
The disconnect string is:
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Cosmology View
My views on Cosmology and Physics
Claims by HDF
Claims About Hubble Deep Field z Values Demonstrate Cosmology Remains Confined To 2-D Or The Line Of Sight And Is Not Valid 3-D Physics
In general physics, velocity is measured by the change in an object's position over a time. The proper velocity is a value with a 3-D vector independent of any observer, while a line of sight velocity can cause a wrong assumption by another observer.
Cosmology must not be confined to only 2-D or linear line of sight measurements to be considered a valid part of 3-D Physics.
The motivation for this post was this quote from an Eric Lerner 2014 study of the HDF galaxy redshifts having z>5:
" Therefore, if the Universe is not expanding, the redshift of light with increasing distance must be caused by some other phenomena – something that happens to the light itself as it travels through space."
The phrase "something happens" should never occur in a paper after elementary school.
HST imaged thousands of faint galaxies in very long exposure images called the Hubble Deep Fields. HST claims to have measured redshifts of z > 5 in these faint galaxies.
These z redshift values from HST are are not consistent with the z calculation for other objects Currently, using z for a value assumes z is the ratio of:
a) a change in a specific wavelength to
b) its correct value.
The phrase "something happens" apparently is a photometric redshift.
Astronomers developed a method of calculating a galaxy redshift without the tedious process of analyzing a spectrum.
The new method is called photometric redshift.
Excerpt from Wikipedia:
A photometric redshift is an estimate for the recession velocity of an astronomical object such as a galaxy or quasar, made without measuring its spectrum. The technique uses photometry (that is, the brightness of the object viewed through various standard filters, each of which lets through a relatively broad passband of colours, such as red light, green light, or blue light) to determine the redshift, and hence, through Hubble's law, the distance, of the observed object.
(excerpt end)
Photometric redshift - Wikipedia
The stated goal is the recession velocity, which is always confined to the line of sight.
The color filters enable finding a similar visible wavelength distribution in a different segment of the spectrum. This comparison of narrow wavelength sets in the continuum cannot reveal any aspect (like value or direction) of the actual velocity of the galaxy.
This exercise with wavelength segments cannot reveal a velocity. This is a false claim. To confirm it, one must actually measure the proper velocity of the galaxy having the assigned velocity. One can be certain this was never done with any of the faint HDF objects.
This z being calculated from a line of sight spectrum can never be a 3-D value.
Hubble's Law is mentioned and it is also invalid 3-D physics. There is no galaxy in the universe with a measured proper velocity to have a valid numerator for Hubble's Constant HC. When Cepheids are used for the distance calculation, the value is always from the statistical averaging resulting in significant margin of error for HC denominator.
Hubble's Law assumes a galaxy velocity can be found using the redshift of an atom in the line of sight, based on the Doppler effect. The Doppler effect is explicitly only in the line of sight and cannot reveal any transverse motion, so it cannot be 3-D.
The notable problems in cosmology for valid Physics in 3-D:
a) Claiming a galaxy velocity requires its actual measurement, which requires many precise position measurements over a long duration to detect its motion in 3-D.
Until cosmology actually has a galaxy having a measured 3-D velocity, cosmology most certainly cannot make claims of a universe expansion, nor can it claim to measure a velocity in a manner suitable for valid 3-D physics.
Not only is cosmology limited to 2-D or the line of sight, but cosmology is a pseudo-science, lacking evidence for its claims. The concepts in cosmology having the word bang, dark, or hole are problematic.
Perhaps I over-reacted to "something happens"
I cannot find the link to the Lerner paper...
date posted 07/13/2021
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TY - JOUR T1 - Hematopoietic Stem Cell Niche Is a Potential Therapeutic Target for Bone Metastatic Tumors JF - Clinical Cancer Research JO - Clin Cancer Res SP - 5553 LP - 5558 DO - 10.1158/1078-0432.CCR-10-2505 VL - 17 IS - 17 AU - Shiozawa, Yusuke AU - Pienta, Kenneth J. AU - Taichman, Russell S. Y1 - 2011/09/01 UR - http://clincancerres.aacrjournals.org/content/17/17/5553.abstract N2 - Despite significant improvements in therapy, the prognosis for cancer with bone metastasis is generally poor. Therefore, there is a great need for new therapeutic approaches for metastatic disease. It has been appreciated that tumor cells metastasize to bone using mechanisms similar to those of hematopoietic stem cells (HSC) homing to bone marrow (e.g., CXCL12/CXCR4). It was recently found that prostate cancer cells target the bone marrow microenvironment for HSCs, or the HSC niche, during metastasis. Of importance, these disseminated prostate cancer cells can be mobilized out of the niche with the use of HSC mobilizing agents. These findings suggest that the bone marrow HSC niche is a potential therapeutic target for metastatic disease. Therefore, a hypothesis worth considering is that agents that can disrupt the interactions between tumor cells and the HSC niche may be efficacious when used in conjunction with standard chemotherapeutic agents. Although further understanding of the tumor-niche interactions is needed, the concept of targeting the niche in conjunction with chemotherapy could open up new possibilities to eradicate incurable metastatic diseases. Clin Cancer Res; 17(17); 5553–8. ©2011 AACR. ER -
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Ice pylons leading from the Endurance
“Two more emperor [penguins] were captured on the following day, and, while Wordie was leading one of them towards the ship, Wild came along with his team. The dogs, uncontrollable in a moment, made a frantic rush for the bird, and were almost upon him when their harness caught upon an ice-pylon, which they had tried to pass on both sides at once. The result was a seething tangle of dogs, traces, and men, and an overturned sled, while the penguin, three yards away, nonchalantly and indifferently surveyed the disturbance. He had never seen anything of the kind before and had no idea at all that the strange disorder might concern him.”
— Ernest Shackleton, South
About Ernest Shackleton
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| 0.975497 |
How To Use A Semi Colon?
How do you use a semicolon example?
Use a semicolon before such words and terms as namely, however, therefore, that is, i.e., for example, e.g., for instance, etc., when they introduce a complete sentence. It is also preferable to use a comma after these words and terms. Example: Bring any two items; however, sleeping bags and tents are in short supply.
Can I use a semicolon here?
The most common use of the semicolon is to join two independent clauses without using a conjunction like and. Do you use a capital letter after a semicolon? The general answer is no. A semicolon should be followed by a capital letter only if the word is a proper noun or an acronym.
Where do you use a semicolon instead of a comma?
Rule: Use the semicolon if you have two independent clauses connected without a conjunction. Example: I have painted the house; I still need to sand the floors. Rule: Also use the semicolon when you already have commas within a sentence for smaller separations, and you need the semicolon to show bigger separations.
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| 0.999772 |
By Guest Author 28/12/2016
When Tony Bromley heads to the hills in January he’s taking along a bag of party balloons and some cardboard coffee cups to help him with some complex measurements involving power lines along the National Grid.
The NIWA atmospheric technician is aiming “to define the sag”.
“Power lines expand with heat and the more power that goes down the line the hotter they get. When that happens the lines sag in the middle of the span between power pylons. It’s essential to know how low the sag could go to ensure the lines aren’t going to touch anything.”
NIWA’s Tony Bromley and Sally Gray (right) and prepare to release a weather balloon. Credit: Dave Allen. Source: NIWA.
Measuring the potential depth of a sag involves complex calculations involving temperature, wind speed and direction, pressure, humidity and solar radiation measurements many metres off the ground. For instance, the wind has a cooling effect but the amount of cooling depends if it is travelling across or along the lines.
All these measurements are used as part of the equation to work out the minimum distance between the lines and other objects, such as trees. Too close means the risk of outages and other issues. A helicopter will operate at the same time taking precise distance measurements via laser.
Mr Bromley and his team will cover 1600km of lines over four weeks from Southland to the Bay of Plenty and Auckland. They will set up temporary meteorological stations at ground level along the length of the lines and then fill party balloons with helium.
The balloons will be attached to the biodegradable coffee cups which contain transmitting sensors sending weather information back to the ground. Once a pre-set height has been reached, some clever programming triggers an electric current that burns through the string, releasing the balloon. The coffee cup falls to the ground, is retrieved and used again.
“The transmitters will only need to ascend to a height of around 100m at most, so we can see where they land. They also transmit a signal giving their actual location on the ground and a small handheld GPS unit can be used to direct us to that location – very useful if the transmitter is hidden in long grass. It is a very efficient use of our technology especially being able to re-use the instruments many times.”
Summer is for scientific fieldwork. This article is from the NIWA Summer Series, sharing the stories of scientists heading into the wild blue yonder.
Featured image credit: NIWA
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Photosynthetic response of young oaks to biochar amendment in field conditions over 3 years
Yumina Tanazawa, Mitsutoshi Tomotsune, Takeshi Suzuki, Hiroshi Koizumi, Shinpei Yoshitake
Research output: Contribution to journalArticlepeer-review
1 Citation (Scopus)
Amendment by biochar made by thermal degradation of biomass is expected to enhance carbon sequestration through stimulating carbon assimilation by plants. We clarified the effect of biochar amendment on the photosynthesis of trees in forest ecosystems. Biochar was applied to young oak trees (Quercus serrata) in temperate deciduous forest at rates of 0, 5, 10 and 20 Mg ha−1 in four plots (C0, C5, C10, and C20). The variation in photosynthetic parameters (the maximum photosynthetic rate: Pmax, maximum carboxylation rate: Vcmax and the potential rate of electron transport: Jmax) and leaf traits (the stomatal conductance: gc, leaf mass per area (LMA) and leaf nutrient concentrations) were examined every month during the growing seasons for 3 years. Pmax generally increased in C5 and C10 and did not increase in C20. Similarly, Vcmax and Jmax increased in C5 and C10 and correlated significantly positively with Pmax, suggesting that biochar amendment basically increased the photosynthetic rate through improvements in physiological activities but that there was a maximum useful dosage. We also found that gc, LMA and leaf nutrient (N, Mg, and S) showed significant positive correlations with Pmax, indicating that an increase in photosynthetic rates would be supported by these leaf traits. However, stimulation of photosynthesis became smaller year by year, indicating that the effects of biochar amendment faded gradually. We concluded that biochar amendment basically improved the photosynthesis of oak trees in the forest through the change of all gc, LMA and leaf nutrient concentrations but declined yearly.
Original languageEnglish
Pages (from-to)116-126
Number of pages11
JournalJournal of Forest Research
Issue number2
Publication statusPublished - 2021
• Biochar
• field conditions
• long-term
• photosynthesis
• tree species
ASJC Scopus subject areas
• Forestry
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Shiny Garage Smooth Clay Lube
Concentrated clay bar lube. The product gives smoothness to a cleaned surface to minimize the risk of causing scratches.
Directions for use:
Use the concentrated product or dilute 100 ml in 1 L of water.
Spray profusely on the surface on which you are going to use the clay.
Do not leave the product to dry and always work on a profusely sprayed surface.
After finishing wash the element with a shampoo with water.
Capacity: 500 ml
Shiny Garage Clay Lube
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S.4. Phenix/DivCon QM X-ray Refinement tool
The impact of advanced, quantum mechanics-based X-ray refinement on our understanding of protein:ligand structure and function
Lance M Westerhoff
QuantumBio Inc.
Successful structure based drug discovery is dependent upon accurate, protein:ligand structure determination and characterization. Often determining or "rescuing" key interactions, while filtering out less important interactions, is extremely important to lead design and optimization.
In conventional x-ray refinement, the geometry of the ligand or fragment within the active site is modeled according to the practitioner's beliefs as expressed in the form of stereochemical restraints provided by the ligand library or CIFile.These restraints are coupled along with a highly simplified functional which lacks even the most rudimentary interactions captured in modern functionals.
Therefore, metal centers, covalently bound species, fragments, and other exotic cases can be particularly difficult to refine correctly without significant human intervention. Traditionally, these deficiencies often lead to "post-refinement processing," such as force field-based structure optimization and docking, with no guarantee that resulting models will continue to fit the experimental density.
When this "plug-in" is installed, QM-based refinement is performed in "real time" during each refinement step. SE-QM - with its inclusion of electrostatics, charge transfer, polarization, dispersion, hydrogen bonds, and so on - is a much more rigorous alternative to conventional stereochemical restraints. At the same time, since the SE-QM method can be applied not only to the ligand or fragment(s) but to the protein, the method captures the influence of the surrounding structure on the ligand (and vise versa).
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Search results
Yard and Garden: Preparing Gardens for Winter
November 11, 2015, 1:39 pm | Richard Jauron, Kendall Evans
Snowy Owls an Early Christmas Present
December 21, 2011, 10:36 am | Rebecca Christoffel, Willy Klein
Preparing Evergreens for Winter
All evergreens, and particularly broad leaf evergreens such as boxwood and rhododendron, are susceptible to winter desiccation. Winter desiccation also is referred to as winter burn or winter browning. Desiccation occurs when the evergreen's foliage loses moisture due to the bright winter sun and harsh winter winds. In winter the plants are not able to absorb enough additional moisture from the soil to replace the water that evaporates from the foliage and stems. In addition to making sure the plants are well watered before the onset of winter there are a few other measures homeowners can take to protect the plants.
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Left Hand Oktoberfest Marzen Lager 6pk Can
Deep in Eldorado Canyon, amidst the soaring sandstone cliffs, our brewers were inspired to create a beer as majestic as the panoramic vistas before them. With hop aromatics as towering as the rock formations, Found Fortune is a hidden trail to hop treasure. Dry-hopped with El Dorado, Galaxy and Citra, this Double IPA boasts a wealth of candied orange, juicy tropical fruits, and fresh-squeezed grapefruit. Take a journey through its haze and find a fortune in every glass. 8.7% abv. 55 IBU.
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How An Altered Strand Of DNA Can Cause Malaria-Spreading Mosquitoes To Self-Destruct
R. Stein, NPR, 2021.
For the first time, scientists have shown that a new kind of genetic engineering can crash populations of malaria-spreading mosquitoes. In the landmark study, published Wednesday in the journal Nature Communications, researchers placed the genetically modified mosquitoes in a special laboratory that simulated the conditions in sub-Saharan Africa, where they spread the deadly disease. The male mosquitoes were engineered with a sequence of DNA known as a “gene drive” that can rapidly transmit a deleterious mutation that essentially wipes out populations of the insects. The goal is to create a powerful new tool to fight malaria, which remains one of the world’s most terrible scourges. “Our study is the first [that] could show that gene-drive technology works under ecologically challenging conditions,” says Ruth Muller, an entomologist who led the research at PoloGGB, a high-security lab in Terni, Italy. “This is the big breakthrough that we made with our study.”
More related to this:
Fighting malaria with gene-drive technology
Widespread haploid-biased gene expression enables sperm-level natural selection
Experimental population modification of the malaria vector mosquito, Anopheles stephensi
Next-generation gene drive for population modification of the malaria vector mosquito, Anopheles gambiae
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Pre-Calculus Help?
A 5-lb force acting in the direction of (5, -3) moves and object just left over 12 ft. from point (0, 6) to (7, -4). Find the work done to move the object to the nearest foot-pound.
a. 11 ft. * lbs
b. 34 ft. * lbs
c. 56 ft. * lbs
d. 61 ft. * lbs
1. 👍
2. 👎
3. 👁
1. work = force * distance
so, how far between the points?
1. 👍
2. 👎
2. direction of force = 5 i - 3 j
make that a unit vector
sqrt (25 + 9) = sqrt (34)
so Force vector F = (5/sqrt34)(5i-3j)
direction of motion vector = 7 i -10 j
make that a unit vector
sqrt(49 + 100) = sqrt(149)
so motion vector
D = (12/sqrt149) (7i-10 j)
Work = F dot D = (5/sqrt34)(12/sqrt149)(35+30)
=.843(65) = 54.8 foot pounds
1. 👍
2. 👎
3. so was the answer choice c. 56 ft?
1. 👍
2. 👎
4. The correct answer is C
1. 👍
2. 👎
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In 1894, a notorious Italian mystic pretended to sprout a third arm. French physiologist Charles Richet sought to identify the ethereal matter that formed it. He dubbed the idiosyncratic material—which he said didn’t resemble a solid, liquid, or gas—ectoplasm, and posited it might be what ghosts were made of. Paranormal investigators seized on the concept:
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What is Melasma?
, , Comments Off on What is Melasma?
Melasma is a skin discoloration that commonly occurs in women caused by the production of too much melanin. It is characterized by brownish pigmentation or patches which form on the face, around the neck, or on the forearm. The proximate sources of Melasma are not yet known. However, there are certain circumstances that may trigger its appearance such as pregnancy, cosmetic allergy, and overuse of anti-seizure medications. It is also referred to as the “mask of pregnancy†or chloasma because the most severe discoloration happens in pregnant women. Melasma in pregnant women may be gone a couple of months after giving birth.
The early signs of Melasma can be noticed through grayish pigmentations that start on the cheeks, forehead, bridge of the nose, above the upper lip, or the chin. Unlike freckles, Melasma are bigger, darker, and closer to each other. It forms in cluster or pattern which can further spread throughout the face.
Melasma is more common in women compared to men. It occurs in people at age 20 to 40 years old. There are three types of Melasma: epidermal, dermal, and mixed. Epidermal Melasma has a well-defined border and can easily be addressed through dermatological remedies. Dermal Melasma is the most common type, appearing as grayish with ill-defined borders. Unlike the former, it responds poorly to treatment making it more possibly to become permanent. Mixed Melasma is combination of brown and bluish patches. It is larger in pattern but can be treated gradually.
A thorough diagnosis of Melasma through skin biopsy would show a deposit of melanin in the dermis. Sometimes the melanin deposit is found in the basal area. The severity of Melasma can also be measured using a special scoring system known as Melasma Area and Severity Index (MASI).
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8 Everyday Tasks to Improve STEM Learning
One of the biggest questions from parents of STEM students is "how do I keep my children learning STEM at home?"
The great news is that there are plenty of activities that children can do at home with their parents without the need of computers or expensive equipment. Here are some suggestions.
1. Cooking - particularly following instructions from recipes is a fantastic way to improve planning skills. Successfully preparing a meal is a very rewarding experience.
2. Assembling or repairing furniture - helping build or repair things around the house helps improve problem solving skills and helps make STEM skills relevant to everyday life.
3. Boardgames - games that involve asking questions, guessing or randomness like dice can improve strategic thinking as well as communication skills.
4. Gardening - growing small plants and vegetables improves understanding of biology as well as planning skills. Gardening also requires a lot of patience and forward thinking.
5. Sport - sport is fantastic for improving strategy and problem solving skills. It is also great for improving fitness and health.
6. Music - learning a musical instrument requires a lot of patience and dedication. Understanding how music is created also improves maths and fine motor skills.
7. Arts and crafts - assembling arts and crafts improves understanding of materials. Crafting also improves fine motor skills.
8. Repurposing/Recycling - give kids an appreciation of the environment by encouraging them to recycle and repurpose discarded objects. Finding ways to keep old items useful is a meaningful problem solving skill.
The key to a rich learning experience is to be actively engaged with your child while they explore their skills. Clear, accurate communication is important for STEM activities.
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Historical linguistics
Historical linguistics, also termed diachronic linguistics, is the scientific study of language change over time.[1] Principal concerns of historical linguistics include:[2]
Historical linguistics is founded on the Uniformitarian Principle, which is defined by linguist Donald Ringe as:[3]
Unless we can demonstrate significant changes in the conditions of language acquisition and use between some time in the unobservable past and the present, we must assume that the same types and distributions of structures, variation, changes, etc. existed at that time in the past as in the present.
Western modern historical linguistics dates from the late-18th century. It grew out of the earlier discipline of philology,[4] the study of ancient texts and documents dating back to antiquity.
At first, historical linguistics served as the cornerstone of comparative linguistics, primarily as a tool for linguistic reconstruction.[5] Scholars were concerned chiefly with establishing language families and reconstructing unrecorded proto-languages, using the comparative method and internal reconstruction.[5] The focus was initially on the well-known Indo-European languages, many of which had long written histories; scholars also studied the Uralic languages, another Eurasian language-family for which less early written material exists. Since then, there has been significant comparative linguistic work expanding outside of European languages as well, such as on the Austronesian languages and on various families of Native American languages, among many others. Comparative linguistics became only a part of a more broadly-conceived discipline of historical linguistics. For the Indo-European languages, comparative study is now a highly specialized field. Most research is being carried out on the subsequent development of these languages, in particular, the development of the modern standard varieties.[citation needed]
Some scholars have undertaken studies attempting to establish super-families, linking, for example, Indo-European, Uralic, and other families into Nostratic. These attempts have not met with wide acceptance. The information necessary to establish relatedness becomes less available as the time depth increases. The time-depth of linguistic methods is limited due to chance word resemblances and variations between language groups, but a limit of around 10,000 years is often assumed.[6] The dating of the various proto-languages is also difficult; several methods are available for dating, but only approximate results can be obtained.
In linguistics, a synchronic analysis is one that views linguistic phenomena only at a given time, usually the present, but a synchronic analysis of a historical language form is also possible. It may be distinguished from diachronic, which regards a phenomenon in terms of developments through time. Diachronic analysis is the main concern of historical linguistics; however, most other branches of linguistics are concerned with some form of synchronic analysis. The study of language change offers a valuable insight into the state of linguistic representation, and because all synchronic forms are the result of historically-evolving diachronic changes, the ability to explain linguistic constructions necessitates a focus on diachronic processes.[7]
In practice, a purely-synchronic linguistics is not possible for any period before the invention of the gramophone, as written records always lag behind speech in reflecting linguistic developments. Written records are difficult to date accurately before the development of the modern title page. Often, dating must rely on contextual historical evidence such as inscriptions, or modern technology, such as carbon dating, can be used to ascertain dates of varying accuracy. Also, the work of sociolinguists on linguistic variation has shown synchronic states are not uniform: the speech habits of older and younger speakers differ in ways that point to language change. Synchronic variation is linguistic change in progress.
Synchronic and diachronic approaches can reach quite different conclusions. For example, a Germanic strong verb like English sing – sang – sung is irregular when it is viewed synchronically: the native speaker's brain processes them as learned forms, but the derived forms of regular verbs are processed quite differently, by the application of productive rules (for example, adding -ed to the basic form of a verb as in walk – walked). That is an insight of psycholinguistics, which is relevant also for language didactics, both of which are synchronic disciplines. However, a diachronic analysis shows that the strong verb is the remnant of a fully regular system of internal vowel changes, in this case the Indo-European ablaut; historical linguistics seldom uses the category "irregular verb".
The principal tools of research in diachronic linguistics are the comparative method and the method of internal reconstruction. Less-standard techniques, such as mass lexical comparison, are used by some linguists to overcome the limitations of the comparative method, but most linguists regard them as unreliable.
Etymology is the study of the history of words: when they entered a language, from what source, and how their form and meaning have changed over time. A word may enter a language as a loanword (as a word from one language adopted by speakers of another language), through derivational morphology by combining pre-existing elements in the language, by a hybrid of these two processes called phono-semantic matching, or in several other minor ways.
An important part of phonology is studying which sounds are distinctive units within a language. For example, the "p" in "pin" is aspirated, but the "p" in "spin" is not. In English these two sounds are used in complementary distribution and are not used to differentiate words so they are considered allophones of the same phoneme. In some other languages like Thai and Quechua, the same difference of aspiration or non-aspiration differentiates words and so the two sounds (or phones) are therefore considered two distinct phonemes.
The principles of phonological theory have also been applied to the analysis of sign languages, but the phonological units do not consist of sounds. The principles of phonological analysis can be applied independently of modality because they are designed to serve as general analytical tools, not language-specific ones.
Studies in historical linguistics often use the terms "conservative" or "innovative" to characterize the extent of change occurring in a particular language or dialect as compared with related varieties. In particular, a conservative variety changes relatively less than an innovative variety. The variations in plasticity are often related to the socio-economic situation of the language speakers. An example of an innovative dialect would be American English because of the vast number of speakers and the open interaction its speakers have with other language groups; the changes can be seen in the terms developed for business and marketing, among other fields such as technology.
The converse of an innovative language is a conservative language, which is generally defined by its static nature and imperviousness to outside influences. Most but not all conservative languages are spoken in secluded areas that lack any other primary language speaking population.
Neither descriptive terms carries any value judgment in linguistic studies or determines any form of worthiness a language has, compared to any other language.
A particularly-conservative variety that preserves features that have long since vanished elsewhere is sometimes said to be "archaic". There are few examples of archaic language in modern society, but some have survived in set phrases or in nursery rhymes.
In terms of evolutionary theory, historical linguistics (as opposed to research into the origin of language) studies Lamarckian acquired characteristics of languages.[9]
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Scrapbooks – A Way To Preserve Memory
Scrapbooking is a practice that has been around for years now and the earliest findings of scrapbooks date back to the 17th century. Scrapbooking is about expressing one’s thoughts, feelings and sentiments by placing pictures/objects together that relate to a memory. Modern scrapbooking has several different purposes however the main reason a person would choose to scrapbook now is to have something special to look back on. When creating a scrapbook the first thing to consider is what is it that you want to remember?
Scrapbook Pic
Found on
A scrapbook is a decorated photo album that preserves stories/ memories behind a photo, it can also hold memorabilia such as tickets, certificates, letters and many other things. A scrapbook is special because it allows memory to be preserved through combining pictures and other objects that relate to the picture to create a story. Scrapbooks as opposed to other forms of preserving memory are special because they’re very personal and allow whoever is making it freedom to create something unique to look back on.
Scrapbooks give the creator the personal freedom to choose how they remember something. For example, the person creating the scrapbook can choose a theme and use stickers, glitter, and many other decorative objects to make a scrapbook page special. Scrapbooking may seem like just a simple fun arts and crafts project however the placements of pictures and objects are important because they contribute to the externalization of memory.
Angling a picture a specific way may seem insignificant to most people but to the creator of the scrapbook it is crucial. Matching pictures witch specific borders or colors is also important because when attempting to relive a memory these elements can help elicit certain feelings that can take you back to that exact moment that the picture was taken.
Scrapbooking is a main way to store memories and be able to access them whenever you’d like. Placing pictures/objects in a specific spot and decorating the page of a scrapbook however you want will affect how you remember things when you decide to look back at the scrapbook in the future. Scrapbooking can be time consuming however it isn’t hard to pick up on it and below is a link to get started:
Scrapbooking For Beginners – Tips + Ideas
4 thoughts on “Scrapbooks – A Way To Preserve Memory
1. Your blog correctly addresses the given prompt on how people exert their memories into the physical way. You example images of a scrapbook are really helpful to show what exactly a scrapbook is.
2. I think you do a great job of explains what scrapbooking is. Also i think you do address the given prompt this is a good blog post. The images and examples is a good touch also.
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Local leaders call for federal funding to prevent potential MTA fare hikes
After Hurricane Ida, the MTA is being called to
stop potential upcoming transit cuts.
Local leaders, including Rep. Alexandria
Ocasio-Cortez, are holding a rally in Queens today to call for federal
funding. They say that if funding isn’t provided to the MTA, it could enact
fare hikes as early as next year.
Rep. Ocasio-Cortez, Rep. Grace Meng and commuters
will be joining to demand that Congress provide the funding for MTA
operations as part of the federal budget.
Budget cuts and pending fare hikes come just after Ida caused power and signal
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What is the mountain ranges of eastern part of India forming a boundary with Myanmar collectively called?
Mountain ranges in the eastern part of India forming its boundary with Myanmar are collectively known as Eastern hills or Purvanchal hills.
Which mountain range of eastern Himalayas formed boundary between India and Myanmar?
The range is an eastern extension of the Himalayan Range System, in north eastern India. It bends sharply to the south beyond the Dihang River gorge, and spreads along the eastern boundary of India with Myanmar. The Purvanchal includes the hill of the Patkai, Barail Range, Naga Hills, Lushai Hills and Jampui Hills.
Which mountains are eastern boundaries of India?
• The Purvanchal Mountains cover the states of Assam, Arunachal Pradesh, Manipur, Tripura, Nagaland, Meghalaya and Mizoram.
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What ranges from the eastern boundary of India?
Purvanchal ranges or the eastern hills are located along the eastern boundary of india. Explanation: The eastern mountains that form a part of the Himalayan ranges are called purvanchal ranges these lies south of the Brahmaputra valley.
Which hills and mountains demarcate the border between India and Myanmar in the eastern part of India Class 9?
What are the three division of Himalayas?
Which is the oldest mountain range in India?
5. The Aravalli Range
• The oldest mountain range of India, The Aravalli Range is also the oldest mountain range in the world. …
• In local language, Aravalli translates to ‘line of peaks’, and spans a total length of 800 km, covering the Indian states of Delhi, Haryana, Rajasthan and Gujrat.
Is a narrow gap in the mountain?
A narrow gap in a mountain range that provides a passage through it is called a ‘Pass’.
What is Eastern Ghats in India?
The Eastern Ghats are a discontinuous range of mountains along India’s eastern coast. … They are eroded and cut through by four major rivers of peninsular India, viz. Mahanadi, Godavari, Krishna, and Kaveri. The cradle of Eastern Ghats is Villupuram district in Tamil Nadu.
What is the difference between Eastern and Western Ghats?
The Western Ghats runs parallel to the western coast in a north-south direction from the Tapi River to Kanyakumari. But the Eastern Ghats runs in a north-east to a south-west direction parallel to the eastern coast from Orissa to the Nilgiri hills. … The Western Ghats continuous and can be crossed through passes only.
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How Purvanchal or eastern hills are formed?
After crossing the Dihang gorge, the Himalayas take a sudden southward turn and form a series of comparatively low hills running in the shape of a crescent with its convex side pointing towards the west. … These hills are collectively called the Purvanchal because they are located in the eastern part of India.
Where is purvanchal located in India?
Purvanchal is a geographic sub-region of Uttar Pradesh that is within the larger Bhojpuri region. It comprises the eastern end of Uttar Pradesh.
Which part of Himalaya is known as Purvanchal?
Purvanchal Himalayas is also known as the Eastern Mountains.
It is a sub-mountain range of Himalayas. These Himalayas lie in the Northeast and south of Brahmaputra river. … It includes five major hills- Patkai hills, Barail range, Manipur, Mizo, and Naga Hills.
What is the name of border line between India and Myanmar?
Border Line Names of India
Border country with India Border Line Names of India
Afghanistan Durand Line – 106 kms
Srilanka Palk Strait –30kms
Myanmar Indo-Burma barrier -1643 kms
Nepal Radoliff Line – 1236 kms
How can I cross Myanmar border from India?
You can go to Myanmar from India by road crossing the Moreh (India side)-Tamu (Myanmar side) overland border at Manipur. The best way is to arrive at Imphal, capital city of Manipur by flight and then take a local cab to Moreh, the border town. From there, you can cross the border to Tamu by walking.
Which Indian state has longest border with Myanmar?
1. Geologically,India was a part of the Gondwanaland. 2. Tamil Nadu has some of the oldest rocks of the world.
Which Indian state shares the largest border with Myanmar?
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List l (Lake) List II (Type)
TsomgoLake 4. Artificial (Sweet water)
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Diets can be difficult to navigate. Since no two people are the same, a healthy diet that satisfies one person won’t necessarily satisfy another. Vegetarians might be perfectly happy without chicken or steak, while some people might shudder at the notion of never indulging in the occasional filet mignon.
1. Eat lots of whole-grain carbohydrates.
dried pasta rice seeds grains varieties
3. Kick added sugars to the curb.
Avoiding added sugars is another way anyone, regardless of their food preferences, can eat healthier every day. Healthy foods such as fruit contain natural sugars, and these don’t pose a threat to overall health. However, added sugars, which the Harvard Medical School notes are found in many foods and can include honey, molasses, and corn syrup, can increase a person’s risk for various conditions and diseases, including obesity, heart disease, and diabetes. Fruit contains fiber that slows the absorption of natural sugars, but the body digests added sugars much more quickly, leading to an uptick in blood sugar levels that can ultimately contribute to diabetes. Added sugars can be found in a host of foods and beverages, including some that aren’t generally considered unhealthy, like bread, certain breakfast cereals, and pasta sauces. When shopping, consumers should read nutrition labels and avoid products with excessive amounts of sugar.
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25th Summer Institute in Statistical Genetics (SISG)
Module 1: Probability and Statistical Inference
Mon, July 13 to Wed, July 15
Module dates: Monday, July 13, 8 a.m. - 1 p.m. Pacific; Tuesday, July 14, 8 a.m. - 1 p.m. Pacific, and Wednesday, July 15, 8 a.m. - 11 a.m. Pacific.
This module serves as an introduction to statistical inference using tools from mathematical statistics and probability. It introduces core elements of statistical modeling, beginning with a review of basic probability and some common distributions (such as the binomial, multinomial, and normal distributions). Maximum likelihood estimation is motivated and described. The central limit theorem and frequentist confidence intervals are introduced, along with simple Bayes methods.
We then cover classical hypothesis testing scenarios such as one-sample tests, two-sample tests, chi-square tests for categorical data analysis, and permutation tests. The course concludes with an overview of resampling methods, such as the bootstrap and jackknife, and a discussion of multiple testing corrections such as false discovery rate control. This module serves as a foundation for almost all of the later modules.
Training in calculus is not a prerequisite for this module, but a willingness to attempt math problems and some comfort with basic algebra will be necessary. Suggested pairing: Modules 4 and 7.
Access 2019 course materials.
Learning Objectives: After attending this module, participants will be able to:
1. Describe the assumptions underlying the Binomial, Multinomial, and Normal probability models.
2. Define sensitivity, specificity and predictive values in the context of a binary screening test for a disease.
3. Explain how the likelihood function can be used for estimation and model selection.
4. Translate scientific questions into appropriate null and alternative hypotheses.
6. Explain and interpret p-values and confidence intervals.
7. Recognize and explain the concepts of confounding and effect modification.
8. Explain the role of computer intensive methods (bootstrap, jackknife, permutation tests) in hypothesis testing and confidence intervals.
9. Explain the false discovery approach to addressing the issue of multiple comparisons in hypothesis testing.
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Question: Is Inbred An Insult?
Is albinism caused by inbreeding?
Even among humans, albinism rates vary with geographic location.
Animals in some areas have extremely high rates of albinism..
What is outbreeding and inbreeding?
Inbreeding refers to mating of related individuals. … Outbreeding refers to matings between individuals from different populations, subspecies, or species. Outbreeding can result in a decline in reproductive fitness known as outbreeding depression, but this is less common than inbreeding depression.
Is Queen Elizabeth an inbred?
What happens if you have a child with a family member?
What race is the most inbred?
Do humans inbred?
What happens when two blood relatives have a baby?
What is an example of inbreeding?
Mating closely related animals (for example, parent and offspring, full brother and sister or half brother and sister) is inbreeding. With less closely related animals (first cousins, second cousins), people disagree about where to draw the line between inbreeding and outbreeding.
Catherine and Prince William’s closest common ancestors are Sir William Blakiston of Gibside and his wife Jane Lambton, making them eleventh cousins once removed, These findings echo Christopher Challender Child’s research, published in 2011.
What will happen if you have a baby with your cousin?
What does it mean to be an inbred family?
What is inbreeding? Inbreeding is the mating of organisms closely related by ancestry. It goes against the biological aim of mating, which is the shuffling of DNA. … Genes determine different aspects of your appearance, like hair and eye colour, as well as biological factors such as your blood type.
Is the royal family inbred?
In humans, the most extreme cases of close inbreeding are frequently found in royal dynasties. Indeed, brother-sister and parent-child marriages were not unusual in ancient royal dynasties such as the Egyptian pharaohs or the Persian dynasty (Middleton, 1962; Bixler, 1982a, 1982b; Ager, 2005).
Can inbreeding be good?
In conclusion, inbreeding can lead not only to depression but also to an improved, healthier, viable phenotype. And, in all likelihood, both deleterious and beneficial traits that appear during brother–sister inbreeding are caused by epigenetic rather than genetic mechanisms.
How did early humans avoid inbreeding?
The results suggest that people deliberately sought partners beyond their immediate family, and that they were probably connected to a wider network of groups from within which mates were chosen, in order to avoid becoming inbred.
Do Amish marry their cousins?
Marrying a first cousin is not allowed among the Amish, but second-cousin relationships are allowed. Marriage to a “Schwartz” cousin (the first cousin once removed) is not permitted in Lancaster County.
Can royals marry commoners?
Why does inbreeding cause defects?
Inbreeding increases the risk of recessive gene disorders They receive one copy of the gene from each parent. Animals that are closely related are more likely to carry a copy of the same recessive gene. This increases the risk they will both pass a copy of the gene onto their offspring.
Does inbreeding cause Down syndrome?
Down syndrome has nothing to do with race, nationality, socioeconomic status, religion, or anything the mother or father did during pregnancy. 4. There is NO correlation between incest and Down syndrome.
What does an inbred person mean?
Inbreeding is the production of offspring from the mating or breeding of individuals or organisms that are closely related genetically. … An individual who inherits such deleterious traits is colloquially referred to as inbred.
Is red hair a sign of inbreeding?
Does inbreeding cause mental illness?
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metal that react more than calcium grit
22.4: The Alkaline Earth Metals (Group 2) - Chemistry …
As with the alkali metals, the atomic and ionic radii of the alkaline earth metals increase smoothly from Be to Ba, and the ionization energies decrease. As we would expect, the first ionization energy of an alkaline earth metal, with an ns 2 valence electron configuration, is always significantly greater than that of the alkali metal immediately preceding it.
WebElements Periodic Table » Strontium » reactions of …
Activity Series Chemistry Tutorial
A more active metal is expected to react faster than a less active metal. Sodium is more active than zinc. Sodium will react faster than zinc. Question 2. Under certain conditions, both copper and magnesium will react with oxygen gas to form oxides.
Groups IIA, IIIA, and IVA
The more active meers of Group IIA (Ca, Sr, and Ba) react with water at room temperature. The products of these reactions are what we might expect. Calcium, for example, loses two electrons to form Ca 2+ ions when it reacts with water.
gcse Reactivity series of metals, metallic activity order …
Although copper doesn''t readily react with dilute hydrochloric acid and dilute sulfuric acid (low in reactivity series), if heated with nasty oily concentrated sulfuric acid you make nasty pungent irritating sulphur dioxide gas and white anhydrous copper(II) sulfate, but this is NOT a reaction on which to base its place in the metal reactivity series and hydrogen gas isn''t produced.
GCSE CHEMISTRY - The Reactivity of Metals with Dilute …
Potassium, sodium, lithium and calcium all react violently with dilute sulfuric acid and dilute hydrochloric acid. It is dangerous to put these metals into an acid. The reaction is similar to the reaction with water, forming the metal salt (either sulfate or chloride) plus H
Calcium Chloride and Aluminum Reaction? | Yahoo Answers
18/12/2012· i need to know the following 1. colour of the calcium chloride before the aluminum was added 2. colour after the reaction 3. How does the aluminum react 4. The limiting and
Is calcium more reactive than zinc? - Quora
Both Calcium and Zinc are electropositive metals forming compound mainly by transfer of electrons. Now the outermost electron in zinc enters the d-orbital while that of Calcium enters s-orbital. Now the shielding power of s-electrons> d-electrons
10 best quail grit for 2020 | Acikod reviews
It took days of going through more than a thousand customer reviews and conducting expert researches to narrow down the list. Weve included a comparison table Alexa Skills Amazon Devices & Accessories Appliances Apps & Games Arts & Crafts & Sewing
Reactions of Main Group Elements with Water - …
Why is calcium more reactive than magnesium? - Quora
Calcium has 20 electrons on its outershell, its electronic configuration is 2,8,8,2. Magnesium on the other hand has 12 electrons with its electronic configuration being 2,8,2. Calcium has 4 shells, while magnesium has 3. Because calcium has more
What happens when metal react with water? - Quora
* Metals react with water and produce a metal oxide and hydrogen gas. * Metal oxides that are soluble in water dissolve in it to further form metal hydroxide. * But all metals do not react with water. Metal + Water → Metal oxide + Hydrogen Metal
4 Ways to Grind Metal - wikiHow
29/3/2019· How to Grind Metal. Grinding metal is a necessary process if you don''t want any sharp edges along a weld line or if you want to polish your piece. As long as you have experience with power tools and a shop to work in, you can grind metal
extraction of metals - introduction - chemguide
16/8/2020· The more reactive the metal is, the more difficult and expensive the extraction becomes. That means that you are having to use a very expensive reducing agent to extract the titanium. As you will see if you read the page about titanium extraction, there are other problems in its extraction which also add to the cost.
Lime slaking system including a cyclone and classifier for …
13/5/1986· A lime slaking system for hydration of lime and removal of unwanted grit, particularly for formation of reactive slaked lime to be used in SO 2 scrubbing of effluent gases, comprising a series of slaking vessels (10, 12) for reacting CaO and water while agitating the reactants, a dilution mix tank (14) receiving a viscous slaked lime slurry from the vessels, diluent for the dilution tank
calcium | Definition, Properties, & Compounds | Britannica
GCSE CHEMISTRY - The Reactivity of Metals with Oxygen …
The Reactivity Series The Reaction of Metals with Air (Oxygen). Potassium, sodium, lithium, calcium and magnesium react with oxygen and burn in air. See the alkali metals and alkaline earth metals. Metals in the reactivity series from aluminium to copper react with oxygen in the air to form the metal oxide.
Rubidium - Metal, that is More Expensive than GOLD! - …
4/9/2016· In water, rubidium behaves much more dangerously than potassium. If you throw even a small piece of rubidium in water, an explosion will immediately occur, because rubidium is much denser than
why does sodium react quicker than magnesium and …
21/2/2013· Calcium is above sodium in the activity series, and is therefore, more reactive than sodium, yet calcium reacts much more slowly with water than does sodium. Amina needs to get the facts right. Calcium is not below sodium in the activity series. In fact, lithium
6.10: Alkaline Earth Metals - Chemistry LibreTexts
Calcium is a soft, gray, nontoxic alkaline Earth metal. Although pure calcium doesn''t exist in nature, calcium compounds are very common in Earth''s crust and in sea water. Calcium is also the most abundant metal in the human body, occurring as calcium compounds such as calcium phosphate and calcium carbonate.
Calcium (Ca) - Chemical properties, Health and …
Factors Affecting Reaction Rates | Chemistry
Smaller pieces of magnesium metal will react more rapidly than larger pieces because more reactive surface exists. 3. (3.1) Depending on the angle selected, the atom may take a long time to collide with the molecule and, when a collision does occur, it may not result in …
Why does Potassium react more Violently than sodium ? …
18/5/2010· Why does Potassium react more Violently than sodium in terms of electrons ?? The reactivity of a metal depends on the energy needed to remove an electron from the outer shell. Both Na and K have 1 electron in their outer shell. However, the outer shell electron in
Metal - Simple English Wikipedia, the free encyclopedia
ALKALINE EARTH METAL | meaning in the Caridge …
alkaline earth metal definition: 1. any of the chemical elements beryllium, magnesium, calcium, strontium, barium, and radium. They…. Learn more. These examples are from the Caridge English Corpus and from sources on the web. Any opinions in the
IB Chemistry notes: Reactivity
These notes were written for the old IB syllabus (2009). The new IB syllabus for first examinations 2016 can be accessed by clicking the link below. 10.2.1: Deduce a reactivity series based upon the chemical behaviour of a group of oxidising and reducing
Can calcium metal reacts with sodium hydroxide? What …
No calcium metal can''t reacts with sodium hydroxide because sodium is more reactive than calcium which means sodium has higher tendency to lose electron than calcium that''s why calcium can''t displace sodium from its aqueous solution.
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Servings: 4
Cooking Time: 20 Minutes
3/4 pound zucchini, peeled and sliced
1 egg, lightly beaten
1/2 cup seasoned breadcrumbs
1/2 cup parmesan cheese, preferably freshly grated
1. Pat the zucchini dry with a kitchen towel.
2. In a mixing dish, thoroughly combine the egg, breadcrumbs, and cheese.
Then, coat the zucchini slices with the breadcrumb mixture.
3. Cook in the preheated Air Fryer at 400 degrees F for 9 minutes, shaking the
basket halfway through the cooking time.
4. Work in batches until the chips is golden brown. Bon appétit!
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5052 aluminum sheet technology features
Forming function
1.The thermal technology of the 5052 aluminum sheet is excellent in plasticity. The temperature of casting and forging is 420~475 degree C, and the thermal deformation of >80% is carried out in this temperature range.
2.The cold stamping function is related to the condition of aluminum sheet. The cold stamping function of annealing (O) condition is outstanding, followed by H32 and H34 condition, while H36/H38 condition is not good.2. Welding function(1) The aluminum sheet has outstanding functions of gas welding, arc welding, resistance welding, spot welding and seam welding, and tends to crystallize cracks during DIG welding. The brazing function is good while the soldering function is poor.(2) the strength and plasticity of the weld are high, and the strength of the weld is 90%~95% of the base metal strength. But the air tightness of the weld is not high. 5A03 aluminum plate is recommended as the welding material, which can improve the air tightness and eliminate the crack tendency.Machining functionThe anneal condition of the aluminum plate is not good, while the cold hardening condition is improved.
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Chang'e 5 returns home with lunar samples
By ZHAO LEI | | Updated: 2020-12-17 02:15
Share - WeChat
A graphic simulation shows the orbiter and returner combination of China's Chang'e-5 probe after its separation from the ascender. [Photo/CNSA]
The first man-made object from Earth to ever reach the moon was the Soviet spacecraft Luna 2. Instead of landing, it actually crashed into the moon in September 1959. The first soft-landing on our celestial neighbor was made by the Soviet Luna 9, in February 1966.
As the result of long-time persuasions by scientists, the Chinese government approved in January 2004 an overall plan for the country's lunar exploration program and officially opened the research and development work.
The first Chang'e probe was launched in October 2007. Since then, China has launched five lunar probes, including Chang'e 5, and one experimental spacecraft.
License for publishing multimedia online 0108263
Registration Number: 130349
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tradition [-s, -'s] n
OFr tradicion, delivery, surrender, handing down, instruction, doctrine.
1. Custom; practice passed through generations; proper mode of behavior; correct way of being.
2. Legend; fairy tale; story passed down through generations.
3. Entity of long ago; something remembered only through legends; thing which no longer exists.
4. Folk wisdom.
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FAQ: What Is The Square Root Of Pi?
What is the square root of pi in math?
It’s approximately 1.77245. It’s an irrational number. That is, there is no fraction or finite sequence of digits that exactly expresses the value. The only way to express it exactly is to write “the square root of pi ”, or to give a formula or algorithm.
What is 3.14 called pi?
Is the square root of pi infinite?
Pi is a geometrical constant. Its official value is 3.14159265358… March 1998 discovery says Pi value is 3.14644660941…. With the official number square root of Pi and squaring of circle are impossible.
What is Pi Squared called?
A circle is a shape formed by a single curved line and every point in that line is the same distance from the center of the circle. To calculate the area of a circle, we need to know the length of the radius. So the formula is area equals pi R squared.
You might be interested: Often asked: How To Lowest Term Square Root?
What is the full number for pi?
Will Pi ever end?
How was Pi calculated?
How do you prove pi?
Why is Pi 22 divided 7?
The pi value in fraction is 22 / 7. It is known that pi is an irrational number which means that the digits after the decimal point are never-ending and being a non-terminating value. Therefore, 22 / 7 is used for everyday calculations. ‘ π ‘ is not equal to the ratio of any two number, which makes it an irrational number.
Is there a 0 in pi?
The first zero in pi occurs at position 32.
What is the symbol for pi?
You might be interested: Quick Answer: What Is The Shortcut Key For Square Root?
How did Archimedes calculate pi?
What is 2 pi r squared?
In geometry, the area enclosed by a circle of radius r is πr 2. Here the Greek letter π represents the constant ratio of the circumference of any circle to its diameter, approximately equal to 3.1416.
What is pi to the 30 decimal places?
What is pi r squared formula?
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2021 Virtual Legislative Meetings May 3-14, 2021
Makada Henry-Nickie
Photo: Makada Henry-Nickie
Makada Henry-Nickie
Governance Fellow
Brookings Institution
Makada Henry-Nickie is a Fellow in Governance Studies at the Brookings Institution within the Race, Prosperity, and Inclusion Initiative. Her research is focused economic inclusion issues, including promoting equity in public workforce systems, expanding equitable access to responsible credit and promoting policies that advance inclusive economic opportunities for disadvantaged families and low-income communities.
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Posts tagged language
Poemage is a visualization system for exploring the sonic topology of a poem. We define sonic topology as the complex structures…
Poemage, visualization, poetry, digital humanities, sonic paterns, language, data
Poemage is a visualization system for exploring the sonic topology of a poem. We define sonic topology as the complex structures formed via the interaction of sonic patterns — words connected through some sonic or linguistic resemblance — across the space of the poem. Poemage was developed at the University of Utah as part of an ongoing, highly exploratory collaboration between data visualization experts and poets/poetry scholars.
(via )
IAU Approves 86 New Star Names From Around the World
IAU, Astronomy, star-names, language, culture, 2017
The International Astronomical Union’s Working Group on Star Names formally approved 86 new names for stars, which are now in the IAU stellar name catalogue. The catalogue now contains the approved names of 313 stars. Traditionally, most star names used by astronomers have come from Arabic, Greek, or Latin origins. Now, the International Astronomical Union (IAU) Division C Working Group on Star Names (WGSN) has formally approved 86 new names for stars drawn from those used by other cultures, namely Australian Aboriginal, Chinese, Coptic, Hindu, Mayan, Polynesian, and South African.
I Can Text You A Pile of Poo, But I Can’t Write My Name - Aditya Mukerjee
culture, unicode, text, writing, language, emoji
The evolution of emoji is impressive and fascinating, but it makes for an uncomfortable contrast when other pictorial writing systems – the most commonly-used writing systems on the planet – are on the chopping block. We have an unambiguous, cross-platform way to represent “PILE OF POO” (💩), while we’re still debating which of the 1.2 billion native Chinese speakers deserve to spell their own names correctly.
We went in search of the world’s hardest language
Medium, language, linguistics, !Xóõ, Ubykh, Tuyuca
How alien can language be?
language, visual-language, Ted-Chiang, Arrival, linguistics, aliens, evolution, culture
The film turns on the visual language of the heptapods, the name given to the aliens because of their seven tentacular feet. In Chiang’s short story, the spoken language looks pretty familiar to Dr Banks; nouns have special markers, similar to the grammatical cases of Latin or German, that signify meaning; there are words, and they seem to come in particular orders depending on what their function is in the grammar of the sentence. But it is the visual language that is at the heart of the story. This language, as presented in the film, is just beautiful; the aliens squirt some kind of squid-like ink into the air which resolves holistically into a presentation of the thought they want to express. It looks like a circular whorl drawn with complex curlicues twisting off of the main circumference. The form of the language is not linear in any sense. The whorls emerge simultaneously as wholes. The orientation, shape, modulation, and direction of the tendrils that build the whorls serve to convey the meaningful connections of the parts to the whole. Multiple sentences can all be combined into more and more complex forms that, in the film, require GPS style computer analysis. The atemporality and multidimensionality of the heptapods’ written language is a core part of the plot. So, could a human language work like this, or is that just too alien?
language, infographic, rosetta, Alberto Lucas López
English, dialect, language, bureaucracy, EU, EC, to precise, translation
“Over the years, the European institutions have developed a vocabulary that differs from that of any recognised form of English. It includes words that do not exist or are relatively unknown to native English speakers outside the EU institutions and often even to standard spellcheckers/grammar checkers (‘planification’, ’to precise’ or ’telematics’ for example) and words that are used with a meaning, often derived from other languages, that is not usually found in English dictionaries (‘coherent ’ being a case in point). Some words are used with more or less the correct meaning, but in contexts where they would not be used by native speakers (‘homogenise’, for example). Finally, there is a group of words, many relating to modern technology, where users (including many native speakers) ‘prefer ’ a local term (often an English word or acronym) to the one normally used in English-speaking countries, which they may not actually know, even passively (’GPS’ or ’navigator’ for ‘satnav ’, ’SMS’ for ’text’, ’to send an SMS to’ for ’to text’, ’GSM’ or even ’Handy’ for ’mobile’ or ’cell phone’, internet ’key’, ’pen’ or ’stick’ for ’dongle’, ’recharge’ for ’top-up/top up’, ’beamer’ for video projector etc).”
Misused English Words and Expressions in EU Publications. European Court of Auditors, Secretariat General Translation Directorate.
Introducing Humdog: Pandora’s Vox Redux (1994)
humdog, 1994, cyberspace, Beaudrilliard, language, mass, gender, utopia, literature, editing, censor
i suspect that cyberspace exists because it is the purest manifestation of the mass (masse) as Jean Beaudrilliard described it. it is a black hole; it absorbs energy and personality and then re-presents it as spectacle. people tend to express their vision of the mass as a kind of imaginary parade of blue-collar workers, their muscle-bound arms raised in defiant salute. sometimes in this vision they are holding wrenches in their hands. anyway, this image has its origins in Marx and it is as Romantic as a dozen long-stemmed red roses. the mass is more like one of those faceless dolls you find in nostalgia-craft shops: limp, cute, and silent. when i say “cute” i am including its macabre and sinister aspects within my definition.
Science is not a method
science, pschology, language, understanding, misunderstanding
Contrary to what most scientists themselves appear to believe, science is not a method; it is an approach to knowledge (Stanovich, 2012). Specifically, it is an approach that strives to better approximate the state of nature by reducing errors in inferences. Alternatively, one can conceptualize science as a toolbox of finely honed tools designed to minimize mistakes, especially confirmation bias - the ubiquitous propensity to seek out and selectively interpret evidence consistent with our hypotheses and to deny, dismiss, and distort evidence that does not (Tavris and Aronson, 2007; Lilienfeld, 2010). Not surprisingly, the specific research methods used by psychologists bear scant surface resemblance to those used by chemists, astrophysicists, or molecular biologists. Nevertheless, all of these methods share an overarching commitment to reducing errors in inference and thereby arriving at a more accurate understanding of reality.
How to design a metaphor
Michael Erard, metaphor, design, metaphor design, language, linguistics, psycholinguistics
“SwiftKey analyzed more than one billion pieces of emoji data across a wide range of categories to learn how speakers of 16…
emoji, chart, unicode, analysis, data, swiftkey, language
“SwiftKey analyzed more than one billion pieces of emoji data across a wide range of categories to learn how speakers of 16 different languages and regions use emoji. The findings in this report came from an analysis of aggregate SwiftKey Cloud data over a four month period between October 2014 and January 2015, and includes both Android and iOS devices”
China bans wordplay in attempt at pun control
language, china, wordplay, idioms, idiomatic, culture, history, cough medicine, puns, control, centr
English minus the non-Germanic words
language, physics, english, geman, germanic, conlang
On the Empire of the Ants
ants, communication, language, science
The weirdest languages
language, NLP, weirdness, linguistics
Voynich manuscript, language, information theory, semantics, patern
Two sciences separated by a common language
language, jargon, communication, boundaries, interdiscipline
One thing that gets in the way of this communication is jargon. Jargon is shorthand that helps people in a field communicate with each other. Needless to say, it can be a huge problem when communicating with the public. But jargon can also be a problem when you’re talking to other scientists. Not only is some of this niche speak meaningless outside its specific field, but in other fields it can sometimes mean something else entirely.
Language shift
language shift, linguistics, celtic, english, monolingual, bilingual, modeling, drift, language
‘Language shift’ is the process whereby members of a community in which more than one language is spoken abandon their original vernacular language in favour of another. The historical shifts to English by Celtic language speakers of Britain and Ireland are particularly well-studied examples for which good census data exist for the most recent 100–120 years in many areas where Celtic languages were once the prevailing vernaculars. We model the dynamics of language shift as a competition process in which the numbers of speakers of each language (both monolingual and bilingual) vary as a function both of internal recruitment (as the net outcome of birth, death, immigration and emigration rates of native speakers), and of gains and losses owing to language shift.
E.O. Wilson on the origins of the arts
language, writing, literature, E.O. Wilson, evolution, nature, humanities, music, art, science
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400 Gradi
400 Gradi is pretty much an institution, known for its Italian food and award-winning pizza, and its Brunswick store is the OG venue. The name of the restaurant refers to the high temperature at which the thin-based pizza is cooked for 90 seconds in a wood-fired oven. Time to time, the restaurant runs masterclasses to learn how to make pizza from scratch.
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In Omega a probabilistic model is a collection of random variables. Random Variables are of type RandVar. There are two ways to construct random variables: the statistical style, which can be less verbose, and more intuitive, but has some limitations, and the explicit style, which is more general.
Statistical Style
In the statistical style we create random variables by combining a number of primitives. Omega comes with a number of built-in primitive distributions. One example is the standard uniform:
x1 = uniform(0.0, 1.0)
x1 is a random variable not a sample. To construct another random variable x2, we do the same.
x2 = uniform(0.0, 1.0)
x1 and x2 are identically distributed and independent (i.i.d.).
julia> rand((x1, x2))
(0.5602978842341093, 0.9274576159629635)
Contrast this with:
julia> rand((x1, x1))
(0.057271529749001626, 0.057271529749001626)
Statistical style is convenient because it allows us to treat a RandVar which returns values of type T (its elemtype) as if it is a value of type T. For instance the elemtype(uniform(0.0, 1.0)) is Float64. Using the statistical style, we can add, multiply, divide them as if they were values of type Float64.
x3 = x1 + x2
Note x3 is a RandVar like x1 and x2
This includes inequalities:
p = x3 > 1.0
elemtype(p) is Bool
julia> rand(p)
A particularly useful case is that primitive distributions which take parameters of type T, also accept RandVar with elemtype T
n = normal(x3, 1.0)
Suppose you write your own function which take Float64s as input:
myfunc(x::Float64, y::Float64) = (x * y)^2
We can't automatically apply myfunc to RandVars; it will cause a method error
julia> myfunc(x1, x2)
ERROR: MethodError: no method matching myfunc(::RandVar..., ::RandVar...)
However this is easily remedied with the function lift:
lift(myfunc)(x1, x2)
Explicit Style
The above style is convenient but has a few limitations and it hides a lot of the machinery. To create random variables in the explicit style, create a normal julia sampler, but it is essential to pass through the rng object.
For instance, to define a bernoulli distribution in explicit style:
x_(rng) = rand(rng) > 0.5
x_ is just a normal julia function. We could sample from it by passing in the GLOBAL_RNG
julia> x_(Base.Random.GLOBAL_RNG)
However, in order to use x for conditional or causal inference we must turn it into a RandVar. One way to do this (we discuss others in [conditonalindependence]) is using ~.
x = ~x_
All of the primitive distributions can be used in explicit style by passing the rng object as the first parameter (type constraints are added just to show that the return values are not random variables but elements. But don't add them to your own code! It will prevent automatic differentiation based inference procedures from working):
function x_(rng)
if bernoulli(rng, 0.5, Bool)::Bool
normal(rng, 0.0, 1.0)::Float64
else bernoulli(rng, 0.5, Bool)
betarv(rng, 2.0, 2.0)::Float64
Statistical style and functional style can be combined naturally. For example:
x =~ rng -> rand(rng) > 0.5 ? rand(rng)^2 : sqrt(rand(rng))
y = normal(0.0, 1.0)
z = x + y
Random Variable Families
Often we want to parameterize a random variable. To do this we create functions with addition arguments, and pass arguments to ciid.
"Uniform distribution between `a` and `b`"
unif(rng, a, b) = rand(rng) * (b - a) + b
# x is uniformly distributed between 10 and 20
x = ciid(unif, 10, 20)
And hence if we wanted to create a method that created independent uniformly distributed random variables, we could do it like so:
uniform(a, b) =~ rng -> rand(rng) * (b - a) + b
# x is distributed between 30 and 40 (and independent of x)
x = ciid(unif, 30, 40)
y = ciid(unif, 30, 40)
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How to remove your cold processed metal from your car
The next time you’re driving along the highway, just take a moment to notice a small black box on the dashboard.
It’s called a heat exchanger.
A heat exchang, or heat exchane, is a device that removes metal from the car.
The device is called a thermoplastic because it’s made from plastics.
It can be used to melt and process metals.
When used correctly, the heat exchangers in your car will heat up metal at the correct temperatures, allowing it to be used in the engine, wheels, tires, suspension, etc. You can read more about heat exchangs on our article on how to remove cold processed metals.
But a heat-recovery device isn’t the only way to get metal out of your car.
Heat recovery is the process of taking metal from metal components and using it in another process, such as a welding process.
Here are the basics of how heat recovery works: Heat recovery involves heating metal to a specific temperature.
You heat up the metal with a metal heat gun.
This gun is basically a big metal object, and the heated metal will be able to melt at the desired temperature.
This is done in a heat recovery device called a thermal mass.
Heat Recovery Heat recovery can be done using heat exchanging.
There are two types of heat recovery: heat recovery through the air.
This involves taking the heat from a car and converting it to air, so that the car can be heated by the air itself.
The air that is being heated can be a mixture of air, water, or a combination of all three.
Air heating involves taking heat from the air and converting that into a certain amount of heat.
Water heating involves heating water by the addition of a mixture, called an enamel or brine, to the water.
When water is heated by air, it will be very hot.
You will get a very high temperature rise in your air that can’t be controlled by any heat-removal device.
If you use air heating, the water that you are using will not have any water molecules in it.
In this case, the air will not be heated.
The heated air will evaporate, leaving behind nothing but water vapor.
Water can also be used as a heat source for welding.
Welding involves heating a metal material with a heat gun and then letting it cool down.
This process is done through a process called metallurgical steaming.
Metallurgical Steaming is the name of the process that is used to remove metals from metals.
It is also called metolysis, because it involves heating the metal.
Heat Transfer Heat transfer is the opposite of heat transfer.
It involves heating or cooling a metal.
This can be achieved by adding heat to the metal to get it to work at a specific heat temperature.
The heat you transfer is called the latent heat of the metal and it is transferred to a material that can absorb heat from it.
The latent heat is then transferred to the materials you are heat transferring to.
The final product is a new metal that can be put into your engine.
You could heat the metal directly by applying it to the engine using a high-pressure jet.
Or you could heat it by adding the metal mixture to a mixture that is heated with a jet.
In the end, the new metal is the same as the old metal.
It won’t melt or corrode as easily as the metal you removed from the engine.
If it doesn’t melt, you could add a coating to the car that absorbs the heat.
The coating could also be a paint, or even paint chips.
This coating is called coatings and is applied to the surface of the new material to reduce heat absorption and allow it to harden.
Heat transfer through the water source Heat transfer involves the process where you use water as a medium to heat metal.
You boil water to a certain temperature and then add a mixture to it.
When the water is boiling, you are adding a mixture into the water and the metal is heated at the same time.
The mixture heats the metal, so it starts to work, and it begins to form a molten mass.
As the metal heats up, the metal will become very hot, so you add a bit more water.
At this point, the mass of the heat metal is not so hot, and as the heat is absorbed, it becomes less hot, making the mass much less hot.
The new metal will then harden and be able go into the engine to be melted and welded to the vehicle.
Heat removal in the air If you heat the air in your house to high temperatures, the metals will not melt and corrode.
This happens because the heat absorbed by the metals creates heat-conducting metal in the surrounding air, which keeps the metals from melting.
The metals can then be removed from a vehicle by simply blowing the metal off.
If a car is heated
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Understanding Life Force – Part Three
Let me say it once again, with feeling: Life Force exhibits vitality and intention.
The spiritual realm is merely a massive collection of life forces engaging each other in different ways. We can look at the spiritual universe and its complexities and try to understand it by the products it has created or we can step back and consider just how individual elements composed of vitality and intention can relate to each other. To put it in a nutshell, let’s see if we can describe the functions of a living being in terms of life forces acting with and against each other.
Let’s take a rather homely example that we are all familiar with, the human body, and try to describe it in terms of life forces acting in alignment and in opposition. If every cell in the body is alive, it has vitality and intention. We are fairly certain about the vitality, but the intention? Well, let’s say the intention is to survive or to succumb or something in between. Let’s just consider cells that perform some function regarding other cells in the body.
How about white blood cells which are involved in recognizing intruders, killing harmful bacteria, and creating antibodies to protect your body against future exposure to some bacteria and viruses? Do you think that this is accomplished without some sort of intention? Intention is cause and if something is causing some result, what other than intention is involved? People who do not feel that cells are alive may postulate some sort of built-in primordial response, but what is that if not proof of a prior intention. White blood cells have a complex function. How do they accomplish these various functions without intentions? If you wish to claim these are pre-programmed functions, whose intentions are being represented here?
How about red blood cells? The red blood cell’s main function is to carry oxygen from the lungs and deliver it throughout our body. Red blood cells also transport waste such as carbon dioxide back to our lungs to be exhaled. Is there an intention involved? Why not?
T cells are another example. T lymphocytes (T cells) are responsible for cell-mediated immunity. B lymphocytes are responsible for humoral immunity or antibody production. They can recognize and have a memory of invading bacteria and viruses. Does that seem to indicate a set of intentions?
Then we have our favorite villains, cancer cells, which uniquely reprogram their cellular activities to support their rapid proliferation and migration and to counteract metabolic and radiation or chemical stress during cancer progression. These cells have evolved the ability to overcome aging by using mechanisms that enable cancer cells to divide indefinitely. Does this sound like an intentional act?
I would like to cut to the chase and say that we should be communicating with various cell groups in the same manner as we communicate with any spiritual being. We should be using reach and withdraw on specific areas of the body and actually attempting to imagine that we are these cells and see what realizations occur. I know when we have done that to injured areas of the body in the past we have often managed to see some miraculous recoveries.
I am suggesting that we should be doing reach and withdraw on cancer cells, bacteria, parasites, and on healthy cells in various body parts to see what the various intentions are and to see if we can get more of these intentions to align for the benefit of the body.
For example, the cancer cell, from what I can see, is a normal cell that mutates. That sure sounds like a response to an overwhelming incident and we have been handling those with SRT for many years. Why not get up close and personal to some cancer cells and see if we can modify their intentions so that they cause no further damage to the body?
If you would like to take on some larger targets, why not look at the intentions that exist in the liver, or lungs or heart? I am sure that the organs are alive and have intentions that affect their vitality and function. If we monitor the vitality of the areas we are working with, we should be able to see what processes are beneficial and which are not.
I feel there is much more that can be done if we bother to look at the vitality and intentions of cells in the body.
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70 ÷ = ten
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Synthesis of Organic-Inorganic Hybrids Based on Perovskite-like Bismuth Titanate H2K0.5Bi2.5Ti4O13·H2O and n-Alkylamines
Iana A. Minich, Oleg I. Silyukov, Veronika V. Gak, Evgeny V. Borisov, Irina A. Zvereva
Research output: Contribution to journalArticlepeer-review
1 Scopus citations
New organic-inorganic hybrids have been synthesized by the intercalation of n-alkylamines (methylamine, ethylamine, n-propylamine, n-butylamine, n-hexylamine, and n-octylamine) into the structure of the protonated and hydrated form of the perovskite-like layered titanate H2K0.5Bi2.5Ti4O13·H2O (HKBT4·H2O). The possibility of the synthesis of the hybrid materials was studied in a wide range of conditions. It was found that interlayer water plays a crucial role in the formation of intercalated hybrids. The obtained compounds were characterized with powder X-ray diffraction analysis; Raman, IR, and NMR spectroscopies; thermogravimetry (TG), TG coupled with mass spectrometry, and CHN analyses; and scanning electron microscopy. It was suggested that the intercalated n-alkylamines exist in the form of alkylammonium ions forming a paraffin-like bilayer with an average tilting angle of ∼77.5°. The obtained HKBT4×RNH2 compounds contain 0.4-0.7 n-alkylamine molecules per formula unit as well as the varied amount of intercalated water. By gentle heating, they can be obtained as dehydrated forms, which are thermally stable up to 250 °C.
Original languageEnglish
Pages (from-to)8158-8168
Number of pages11
JournalACS Omega
Issue number14
StatePublished - 14 Apr 2020
Scopus subject areas
• Chemistry(all)
• Chemical Engineering(all)
Dive into the research topics of 'Synthesis of Organic-Inorganic Hybrids Based on Perovskite-like Bismuth Titanate H<sub>2</sub>K<sub>0.5</sub>Bi<sub>2.5</sub>Ti<sub>4</sub>O<sub>13</sub>·H<sub>2</sub>O and n-Alkylamines'. Together they form a unique fingerprint.
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Evans Estyn
3 results
“It involved young couples going to bed together, with certain precautions for chastity, up to and including boarded partitions, as a trial run for marriage.” Photograph: Getty Images
When we speak of “bundling” today, it usually refers to the sale in groups of computer products or services, typically including broadband. But(...)
The Door Was Open And The House Was Dark is the title of the third-last poem in Human Chain. Seamus wrote it in memory of his dear friend David Hammon(...)
Clare cottage. “The Room was where we kept the family pictures, mainly. It tended to be cold unless there was a fire lit, which was seldom.”
In the house where I grew up, as in most country houses of the time, there was a room known only as “The Room”. Townies might have called it the “sitt(...)
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Renewable energy. It’s the future of power. And it’s the solution for sustainability.
by Jul 26, 2021Uncategorized
But what different types of renewable energy are there, and what else is coming?
Solar energy is drawn from the sun, and while we all might feel we don’t enjoy anything like nearly enough sun in this country, there is more than enough to power homes and buildings. In fact, you may be surprised to learn that we produce more solar power here in the UK than in sunny Spain!
Solar panels and new style Integrated Roof Panels capture the energy from the sun and convert it into power. Solar panels can be placed on the roofs of buildings or may be part of larger ‘solar farms’ on rural land. Solar power is infinite and converting it to power has no negative or harmful implications, which makes it such an appealing alternative to non-renewables.
Wind turbines convert wind into power. A bit like the sun, plenty of wind is pretty much guaranteed, and its conversion to power is effective and harmless. Even light winds are enough for wind turbines to work, as their blades turn, creating kinetic energy which is then converted to electrical energy. Wind turbines can be individual, to power a small property or area, or operate as large wind farms creating vast amounts of power.
Hydrogen is a clean, renewable energy source. Whilst it is a gas, unlike other natural gases, when it is burnt it only creates water vapour rather than carbon dioxide which contributes towards climate change. Hydrogen can be produced from natural gas, other renewables such as solar and wind, or nuclear. It is already used in some countries to fuel cars. To make hydrogen a mainstream energy source however, solutions need to be found to infrastructure, storage, and transportation challenges.
Tidal energy
Operating like wind, tidal energy offers the possibility of converting the natural power and movement of tides into electrical energy using tidal turbines. The possibilities are being researched, including by an engineering team at the University of Oxford. The benefits include the predictability of tides, and the challenges include the placement of tidal turbines and their impact on the eco-system.
Renewable energy solutions will evolve. But we can power your home or housing estate with renewable energy right now, with our leading solar energy service.
#zerocarbon #greentechnology #solarenergy
If we can help you with solar, get in touch.
Simon Peat
Simon Peat
CEO Project Better Energy
Green technology entrepreneur and inventor. Meeting the sustainability challenges of tomorrow with renewable energy solutions today.
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Developing cell-penetrating miniproteins as a new class of therapeutics
Project: Research project
Project Details
Current protein therapeutics have a major limitation: they generally cannot cross the cellular membrane or interact with cytosolic targets. The ability to design protein therapeutics that enter the cell cytosol would enable new therapeutic strategies across many disease areas, including cancer, autoimmunity, and neurological disease. Therapeutic “miniproteins” (30-60 residues in length) have the potential to address this challenge, and several miniproteins capable of efficiently reaching the cell cytosol have recently been identified. However, we lack a general understanding of the “design rules” for cell-penetrating miniproteins, limiting the development of this class of molecules. Furthermore, current approaches to measure cytosolic delivery require measuring each protein individually, which is slow and labor intensive. This makes it impossible to test large numbers of miniproteins to develop a robust, quantitative understanding of the determinants of cytosolic delivery. In this exploratory project, we will develop a new approach to measure delivery for each different protein in a large mixed pool, using argeted mass spectrometry to individually identify each miniprotein sequence. In our approach, a oluble ixed pool containing thousands of designed miniprotein sequences is incubated with cells,
and miniproteins that enter those cells are captured by a cytosolic target. Miniproteins captured by the target are then purified out of the cellular contents and identified and quantified using targeted proteomics. The amount of each protein in the captured sample (relative to the starting sample) will provide a quantitative measure of delivery efficiency. This approach is unprecedented, and we will test and optimize this approach using different positive and negative control miniproteins, different library sizes, and different cell lines.
With this method in hand, we will use approaches we previously pioneered to computationally design thousands of candidate cell-penetrating miniproteins with intentionally diverse sequence and structural properties. We will then quantify cytosolic delivery for these new proteins using our new high-throughput approach, creating unprecedented large-scale data on delivery efficiency. We will then use these data to build machine learning models that predict miniprotein delivery based on sequence and structural properties. Finally, we will repeatedly iterate, designing new miniprotein libraries based on our predictive models of delivery, testing these designs
using our high-throughput experimental approach, and further updating our models. This iterative design-testlearn approach will build a robust, predictive understanding of the determinants of delivery. Ultimately, the ability to design cell-penetrating miniproteins will unlock a wide range of new therapeutic targets inside the cell.
Effective start/end date8/1/217/31/23
• National Institute of General Medical Sciences (1R21GM143560-01)
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Tech: Technology that takes carbon dioxide out of the atmosphere and turn it into valuable chemicals and fuels — (Report)
Burning fossil fuels such as coal and natural gas releases carbon into the atmosphere as CO2 while the production of methanol and other valuable fuels and chemicals requires a supply of carbon. There is currently no economically or energy efficient way to collect CO2 from the atmosphere and use it to produce carbon-based chemicals, but researchers at the University of Pittsburgh Swanson School of Engineering have just taken an important step in that direction.
The team worked with a class of nanomaterials called metal-organic frameworks or “MOFs,” which can be used to take carbon dioxide out of the atmosphere and combine it with hydrogen atoms to convert it into valuable chemicals and fuels. Karl Johnson, the William Kepler Whiteford Professor in the Swanson School’s Department of Chemical and Petroleum Engineering, led the research group as principal investigator.
“Our ultimate goal is to find a low-energy, low-cost MOF capable of separating carbon dioxide from a mixture of gases and prepare it to react with hydrogen,” says Dr. Johnson. “We found a MOF that could bend the CO2 molecules slightly, taking them to a state in which they react with hydrogen more easily.”
The Johnson Research Group published their findings in the Royal Society of Chemistry (RSC) journal Catalysis Science & Technology. The journal featured their work on its cover, illustrating the process of carbon dioxide and hydrogen molecules entering the MOF and exiting as CH2O2 or formic acid — a chemical precursor to methanol. For this process to occur, the molecules must overcome a demanding energy threshold called the hydrogenation barrier.
Dr. Johnson explains, “The hydrogenation barrier is the energy needed to add two H atoms to CO2, which transforms the molecules into formic acid. In other words, it is the energy needed to get the H atoms and the CO2 molecules together so that they can form the new compound. In our previous work we have been able to activate H2 by splitting two H atoms, but we have not been able to activate CO2 until now.”
The key to reducing the hydrogenation barrier was to identify a MOF capable of pre-activating carbon dioxide. Pre-activation is basically preparing the molecules for the chemical reaction by putting it into the right geometry, the right position, or the right electronic state. The MOF they modeled in their work achieves pre-activation of CO2 by putting it into a slightly bent geometry that is able to accept the incoming hydrogen atoms with a lower barrier.
Another key feature of this new MOF is that it selectively reacts with hydrogen molecules over carbon dioxide, so that the active sites are not blocked by CO2. “We designed a MOF that has limited space around its binding sites so that there is not quite enough room to bind CO2, but there is still plenty of room to bind H2, because it is so much smaller. Our design ensures that the CO2 does not bind to the MOF but instead is free to react with the H molecules already inside the framework,” says Dr. Johnson.
The Pitt Center for Research Computing contributed computing resources.
Story Source:
Materials provided by University of Pittsburgh. Note: Content may be edited for style and length.
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Pathways Statement
Hands-on Practical Courses that are backed up with theory to help students gain qualifications directly linked to their chosen pathway.
This includes Gateway which involves a work placement and related theory or Dual Enrolment –where students are enrolled at School and usually Polytechnic. Transition courses are school-based preparing students for life after school.
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There isn’t one right way to create a culture of learning. That’s why we’ve collected stories from around the world. While each story is unique to the organization, they all share a common thread - a passion for skills development and their people. Each customer story has overcome a common hurdle to learning. These are their stories. May you be as inspired by them, as we are each day.
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Казино онлайн
Казино онлайн
Initial Combinations in Blackjack at Live Casino
How many card combination can you get when playing blackjack? How often do they form? What probability of winning or losing does each one of them have? In this article, we will give you answers to several interesting questions concerning initial hands at blackjack. Note that the statistical data mentioned in the article is correct for blackjack with six decks only.
Frequency of initial combination being dealt
Two cards the dealer deals to you at the beginning of every round can form 34 different combinations: Hard hands from five to nineteen, Soft hands from Ace/Two to Ace/Ten, and pairs of Aces to Tens (“ten” means any card that is worth 10 points).
Initial Combinations in Blackjack at Live Casino
These combinations are formed with different frequency. As the deck has more 10-point cards, a pair of tens comes up more frequently, in 9.2% of all cases – which is pretty good for players.
The second place goes to twelve and thirteen (8.1%) followed by Hard fourteen, fifteen (7%) and sixteen (6%) points. In general, the first two cards bring from twelve to sixteen points most often. As these combinations require making tough decisions, you should learn the basic strategy. Blackjack comes up in about 4.7% of all cases. Pairs of equal cards (1%) and “soft” hands come up the least often.
Theoretical advantage of different combinations
Now let’s see what chances of winning or losing certain hands have. Blackjack with almost 150% occupies the top position in this rating. It’s paid 3:2.Blackjack is followed by twenty points formed from Ace and Nine and pair of Tens (around 60%). The third place goes to “hard” eleven and nineteen points (around 23%).
Soft hands and pairs from Twos to Eights are unbeneficial combinations for the player. “Hard” hands with twelve to sixteen points are the worst for the player: the house edge is that case is around 30-40%.
Profitability of combinations
Taking into account frequency of combinations and probability of winning/losing, we can calculate profitability of every combination, i.e. determine which initial combinations bring you the largest winnings or losses.
The following hands are the most beneficial for the player (in the order of decreasing profitability): blackjack, pair of Tens, Eleven, Nineteen, Ten, Ace/Nine, Ace/Eight, pair of Aces, pair of Fives, and pair of Nines.
The largest losses are caused by the following hands: “hard” Twelve through Sixteen, Five, Six and Seven; “soft” Thirteen through Seventeen; pairs of Twos, Threes, Fours, Sixes, Sevens and Eights; “hard” Seventeen or Eighteen are not welcome either.
We hope that this information on different start combinations will help you understand and play blackjack better.
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MATLAB Answers
build an array y depending on x
2 views (last 30 days)
Mina on 4 Jun 2021
Answered: the cyclist on 4 Jun 2021
Build an array y by doubling all the elements of a vector x that are positive and adds 10 to all the elements of x that are negative. Note that x could be any length.
Initialise x as indicated above and y to an array of zeroes for the same number as elements as x.
Use a loop to change each element of y as described above. Use the variable i as your loop counter.
Mina on 4 Jun 2021
x = input();
for i = 1:x
if x(i) >= 0
y = x(i)* 2;
y = x(i) + 10;
Sign in to comment.
Answers (1)
the cyclist
the cyclist on 4 Jun 2021
You have a few problems to fix:
As you can see in its documentation, the input function requires you to include some prompting text, such as
input('Enter x: ')
Instead of
for i = 1:x
you want to loop from 1 to the number of elements in x (not from 1 to x itself). You should be able to figure that out. It is not difficult.
Finally, you keep overwriting the same scalar value of y, over and over. Instead, you also want to define a vector y, and only write to each element in turn. Again, I bet you can figure that out (since you are doing something similar with x).
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iBanFirst Blog
4 advantages of real-time exchange rates for SMEs and mid-caps
24 October 2018
Any SME or mid-cap relying on their bank for foreign exchange transactions, and international transfers in particular, can testify that the system in place is both opaque and costly. Today, however, a number of economical and transparent solutions provide SMEs and mid-caps with real-time exchange rates, enabling them to make transactions at the most opportune moment in terms of market value.
What is the real-time exchange rate?
Before going into greater detail, we need to better understand precisely how exchange rates work, and indeed how having access to real-time exchange rates can provide an advantage. Let’s start by defining these concepts.
An exchange rate is defined as any operation enabling you to convert one currency to another. The exchange rate can therefore be seen as the conversion rate from currency A to currency B, and it is used to calculate the amount of currency B obtained in exchange for a unit of currency A.
The real-time exchange rate refers to the actual rate of a particular currency, in constant flux, observed at a given moment in time. It is now possible to track real-time exchange rates online with minimal effort, notably through platforms like iBanFirst. This differs markedly from what is termed “the interbank exchange rate” (or the "mid-market"), which is the gross rate at which banks exchange currencies.
Why SMEs and SMIs do not benefit from the exchange rate in real time today?
As we have just seen, real-time exchange rates fluctuate according to supply and demand on the market, with values changing constantly. However, today, SMEs and mid-caps do not always benefit from real-time exchange rates when trading in foreign currencies. Why is this so?
This is partly because access to bank trading rooms is reserved for larger companies. The latter benefit from a range of financial services, including real-time currency pair quotes. They can therefore take advantage of favourable market conditions for their foreign currency transactions.
SMEs and mid-caps, on the other hand, do not necessarily have the critical volume of foreign exchange transactions that would grant them access to trading rooms. According to the current system, which is both obscure and insufficiently adapted to their needs, SMEs and mid-caps pay significant fees on each transaction made in foreign currencies.
This presents such businesses with a familiar conundrum. Once the instruction has been given to the bank for its supplier’s payment order, the issuing company does not know when the transaction will be carried out, and therefore does not know the rate at which the exchange will take place or the margin to be deducted by the bank. The actual cost of the transfer will only be known after the fact.
The 4 benefits of real-time exchange rates for SMEs and mid-caps
As mentioned above, the real-time exchange rate reflects the situation on the financial markets. If SMEs can gain access to it, they can use the exchange rate to carry out their transactions at the right moment. Offering SMEs and mid-caps the exchange rate conditions they deserve is at the very heart of iBanFirst’s mission.
Being able to benefit from an exchange rate in real time offers companies four specific advantages:4-advantages-750x300
• Knowledge
Knowing the exchange rate at which a transaction will be carried out, ahead of time, is the first advantage. This provides transparency in foreign exchange transactions, something SMEs and mid-caps usually miss out on.
• Choice
As the company will benefit from real-time data presented in a transparent manner, they will be able to carry out their transactions at the most opportune moment for them.
• Insight
With this added transparency, it is possible to seek insight from intermediary institutions, such as iBanFirst, which provide factual information and allow them to make an informed decision with regard to their transactions.
• Savings
As the company is equipped with all the information needed to execute their transactions at the right time, it can leverage this awareness to regularly save money on its transactions.
But how is it that an institution like iBanFirst can offer SMEs and mid-caps access to real-time exchange rates when banks cannot?
Technological developments have made it possible to democratise access to foreign exchange-related financial services, including real-time exchange rates. This has led to the emergence of new financial institutions, such as iBanFirst. Thanks to the volume of our clients’ transactions, we can offer them access to trading rooms, and therefore allow them to benefit from real-time exchange rates, opening up a whole host of possibilities.
Moreover, because a payment services institution like ours is not weighed down by a traditional bank’s fixed historical costs, the rates levied on foreign exchange transactions is significantly lower than those applied by banks.
SMEs and mid-caps finally have access to the conditions they deserve, while saving on their foreign exchange transactions. If you too want to optimise your foreign exchange transactions, our account managers will be happy to tell you more.
Get real-time exchange rates instantly
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The Guardian Quick Crossword July 28 2021 Answers
If you are searching for: The Guardian Quick Crossword July 28 2021 Answers. Give your brain some exercise and solve your way through brilliant crosswords published every day! Increase your vocabulary and general knowledge. Become a master crossword solver while having tons of fun.
The Guardian Quick Crossword July 28 2021 Answers:
Audacious 4 letters BOLD
Cordial 8 letters AMICABLE
Keen to find out 7 letters CURIOUS
Long-handled broom made of twigs 5 letters BESOM
At right angles to a ship 5 letters ABEAM
Chinwag (abbr) 6 letters CONFAB
Configuration of stars as seen from Earth 13 letters
Angle formed by the junction of two branches of a tree 6 letters CROTCH
Get it down you! 5 letters EATUP
Device used to invert an image 5 letters PRISM
Unsophisticated young woman 7 letters INGENUE
Go here in disgrace 8 letters DOGHOUSE
Checks closely 4 letters VETS
As luck would have it 8 letters BYCHANCE
Syd Little’s old partner 5 letters LARGE
Children’s game that leaves one standing! 13 letters
A floating bedroom? 5 letters CABIN
Type of long-grained rice 7 letters BASMATI
US television award 4 letters EMMY
Clever remark 6 letters BONMOT
Snatches 8 letters SNIPPETS
Nightingale’s calling? 7 letters NURSING
Get even 6 letters AVENGE
Pace 5 letters TEMPO
Slight trace of colour 5 letters TINGE
Imitated in every way 4 letters APED
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| 0.975225 |
The Artistry of Fish Radiography
At times, science is an artform unto itself. So it is for a series of x-rays of fish by the Smithsonian Maritime Museum that have allowed scientists to build a comprehensive narrative of the diversity of fish. Tracing the changes in number of vertebrae, fin position and countless other variations, the striking sequence dives through to the depths of fish evolution. Compiled by the Smithsonian Institute in Ichthyo - The Architecture Of Fish, it is a stunning compendium of science and art.
The Scientific Method
X-ray images allow the study of fish anatomy without dissection or alteration of the specimen. Radiographs may be prepared for any number of any species, so allowing a researcher to compare various features both intra- and inter-species. Images are designed to follow scientific convention, not artistic flair. There is always one specimen per frame, and the fish is always facing to the left. A beam of x-rays is generated and focused on the specimen. As tissue density determines absorption of x-rays, the bones of the specimen materialise most readily, creating the images. Characteristics of the species can then be readily seen, assessed and compared. Relative size and shape of bones and fins, the presence or absence of teeth, biological elements are tabulated and archived.
Art From Science, Philosophy From Art
From these images, the beauty, intricacy and diversity of the patterns of nature become self-evident. It is a natural union between science and art. The metaphysical element of evolution emerges from the arranged sequence, the sublime artistry of constant adaptation through mutation. One abstracts to the general nature of biology - of the continuous change, of the possibilities of the future, the direct line of ancestors - it is a sombre thought. One realises their position in the great chain of life, as an infinitesimal yet influential piece of the greatest whole.
Words | Rob Woodgate
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How to read MLB jerseys in a million, and why it will be the hardest to decipher
Aug 18, 2021 calculation
On a cold, damp night, there’s no way you can see the Giants from a seat at Dodger Stadium, but if you want to know how they did it in their epic playoff series against the Yankees, the most obvious answer is to look at the jersey numbers on their jerseys.
The Giants wore their jerseys with their numbers, not their initials, because the league does not allow jersey numbers in the top two rows of a jersey.
But as the season drew to a close, the Giants were faced with the dilemma of whether to keep their jerseys numbered, or keep them with their initials.
As it turned out, the answer was obvious.
The Giants wore the jersey number with their number on it, and the Yankees were forced to play in the “Mets-Yankees” jersey series.
If you know anything about baseball, you know that the jersey series is an excellent way to identify teams.
It’s an easy way to distinguish the teams on a team by their number, and it’s also a good way to compare the teams, since teams are usually divided by a single number.
Because the Giants wore both numbers on the same jersey, the Yankees and their opponents had to use the same number of jersey numbers.
But because the jerseys were numbered from left to right, it’s possible that the numbers on both jerseys were the same, even though they were different numbers.
When a team wears a jersey that has the numbers from the left to the right, they’re usually the same.
When they wear the same numbers from right to left, they’ve changed the numbers.
The numbers on one side of the jersey match the numbers in its middle, and on the other side the numbers match the ones on the right.
But when the numbers are different on the opposite side, they match the opposite numbers.
When the jersey on the left side is “METS-Yankee,” the numbers will be different on that side of their jersey.
When it’s “MET-Yanka,” the number on the side that’s opposite will match the number of the opposite number.
When it comes to comparing the teams with different jersey numbers, the number “9” in the middle is the number from the middle of the Yankees jersey to the end of the Giants.
There are a couple of ways to interpret the numbers 9 and 10 on the Giants jersey.
One way is that the Giants have to wear the number 9 on both sides of their jerseys in order to identify them as the Yankees.
But if they’re wearing the numbers 10 on both left and right sides of the shirt, then they’ve worn the numbers 8 on both right and left sides of both jerseys.
This means that if the Yankees wear a jersey with numbers 9 on the inside and numbers 10 in the outside, and they wear their numbers with numbers 8 and 10 inside, they can identify them both as the Giants and as the Tigers.
The Yankees, in turn, can identify the Giants by the numbers 1 and 3 on their jersey from the outside.
A different way to interpret numbers 9 in the Giants shirt would be that the Yankees are the Yankees because they wear numbers 9 inside their jersey and numbers 9 outside.
However, if the numbers 11 and 12 are on the outside and on both ends of their shirts, then that would also mean that the team is the Yankees (assuming it wears numbers 9, 11, and 12).
What’s the difference between numbers 2 and 4?
As the season went on, the numbers 2 through 4 became more and more important.
The first number became important for identifying a team in a playoff series because it represented their starting lineup.
Numbers 2 and 3 were used to represent the pitchers, while numbers 4 and 5 were used as the catchers.
The teams that wore numbers 2 or 3 were the ones that started with the number 4.
And the teams that had numbers 4 on their shirts were the teams who started with numbers 2.
The numbers 2, 3, and 4 were assigned to the first two rows.
So if you were in the first row, the two numbers would be numbers 2-4.
But the numbers 3, 4, and 5 would be on the second row.
The only exception to this rule was the teams wearing numbers 2 on their front and numbers 3 on the back.
So when the Giants wear numbers 2 inside their jerseys and numbers 1 on the front, then the number 3 would be number 2 on the jersey.
The number 4 would be the number 1 on that jersey.
And so on.
While the first three numbers on a jersey are always the same as the numbers used for their number in the center, the last three numbers are always different than the number used on the number outside.
The same is true for numbers 4, 5, and 6.
The third number of each number is different from the last number used for
By admin
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What can I do about my neighbor's trees blocking my solar panels?
Solar access rights and regulations vary considerably across the United States. Many states and municipalities protect solar access rights through statutes and ordinances that regulate vegetation obstruction of solar panels. Where such public regulation does not exist, condominium or homeowners associations may adopt covenants, conditions, and restrictions to protect solar access rights. In both public and private settings, regulation often depends on the chronology of the matter. That is, if Neighbor A’s tree existed at its current stature before Neighbor B installed his solar panel, then the law may rule in favor of Neighbor A. However, if Neighbor A planted trees or had young trees that grew up to obstruct Neighbor B’s existing solar panel, then the law may rule in favor of Neighbor B. Many states also permit solar easements, which are agreements between landowners to assure access to sunlight by restricting obstructive vegetation. These easements are recorded with the deed, permanently restricting the land use.
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| 0.997061 |
Strength of Arms
The Drúadan Forest #34 (x3)
Play only if each hero you control has a printed resource icon.
Action: Ready each ally in play.
And so the companies came and were hailed and cheered and passed through the Gate, men of the Outlands marching to defend the City of Gondor in a dark hour... –The Return of the King
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| 0.760671 |
01683nas a2200157 4500008004100000245007900041210006900120300001000189520105800199653001601257653002301273653008001296653002001376100001501396856011401411 1998 eng d 00 aNew and known Nemertodermatida (Platyhelminthes-Acoelomorpha) - A revision 0 aNew and known Nemertodermatida PlatyhelminthesAcoelomorpha A rev a55-92 3 aDescribed in 1930-31 by Steinbock who considered it the most primitive bilaterian, the turbellarian genus Nemertoderma is known for its role in platyhelminth phylogeny as much as for its muddled taxonomy. On the basis of material collected in the Mediterranean, Atlantic and Pacific Oceans since 1964 this paper re-diagnoses the known 4 genera and 7 species (Nemertoderma bathycola Steinbock, 1930-31; N. westbladi Steinbock, 1938; N. psammicola Sterrer, 1970 (syn. N. rubra Faubel, 1976); Meara stichopi Westblad, 1949; Meara sp. (see SMITH et al., 1994); Nemertinoides elongatus Riser, 1987; and Flagellophora apelti Faubel Be Dorjes, 1978), describes one new genus with 2 new species (Ascoparia neglecta n. g., n. sp. and A. secunda n. sp.), and provides observations from living material on morphological variability, body size vs. reproductive state, statocyst structure and statolith variability, and sperm morphology and dimorphism. The paper concludes with diagnoses for the known taxa of Nemertodermatida, including the new family Ascopariidae. 10 afree-living 10 amarine systematics 10 anew species PHYLOGENETIC SIGNIFICANCE ULTRASTRUCTURE TURBELLARIA MORPHOLOGY 10 aPlatyhelminthes 1 aSterrer, W uhttps://acoela.myspecies.info/en/content/new-and-known-nemertodermatida-platyhelminthes-acoelomorpha-revision
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| 0.87926 |
Use the following coupon "FIRST15"
Temple of Athena Nike in Athens.
Choose a work from this week’s module that illustrates a significant cultural influence on its creation and discuss its historical context. I choose the Temple of Athena Nike in Athens. How did the culture in which the work was created influence the work? (What particular ideologies played a role in its creation and where do you see this influence reflected in the work you chose?) Make sure to point to specific examples of the influence of the culture on the work. Use details in your explanation.
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| 0.999558 |
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