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https://en.wikipedia.org/wiki/Materials%20testing%20reactor
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A materials test reactor (MTR) is a high power research nuclear reactor.
Examples
Materials testing reactors include:
The Materials Testing Reactor (MTR), an early reactor that operated in Idaho from 1952-1970.
Dounreay Materials Testing Reactor, a Dido class reactor in the United Kingdom.
ETRR-2, at the Nuclear Research Center in Inshas, Egypt.
Jules Horowitz Reactor, under construction at the Cadarache nuclear facility in southern France.
Research reactor in Petten, the Netherlands.
PINSTECH National Laboratory (PNL) in Pakistan.
Reactor Technology Complex of the Idaho National Laboratory in Idaho, United States.
RV-1 nuclear reactor in Venezuelan Institute for Scientific Research, Venezuela
SAFARI-1, outside of Pretoria, South Africa, also used to produce medical isotopes.
RSG G.A Siwabessy in Serpong, Indonesia.
See also
List of nuclear reactors
External links
Ne.anl.gov: MTR Reactors designed by the Argonne National Laboratory
Docs.google.com: Materials Testing Reactor
M
Nuclear technology in France
Nuclear technology in Pakistan
Nuclear technology in South Africa
Nuclear technology in the United States
Nuclear technology in Egypt
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https://en.wikipedia.org/wiki/Positive%20and%20negative%20sets
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In measure theory, given a measurable space and a signed measure on it, a set is called a for if every -measurable subset of has nonnegative measure; that is, for every that satisfies holds.
Similarly, a set is called a for if for every subset satisfying holds.
Intuitively, a measurable set is positive (resp. negative) for if is nonnegative (resp. nonpositive) everywhere on Of course, if is a nonnegative measure, every element of is a positive set for
In the light of Radon–Nikodym theorem, if is a σ-finite positive measure such that a set is a positive set for if and only if the Radon–Nikodym derivative is nonnegative -almost everywhere on Similarly, a negative set is a set where -almost everywhere.
Properties
It follows from the definition that every measurable subset of a positive or negative set is also positive or negative. Also, the union of a sequence of positive or negative sets is also positive or negative; more formally, if is a sequence of positive sets, then
is also a positive set; the same is true if the word "positive" is replaced by "negative".
A set which is both positive and negative is a -null set, for if is a measurable subset of a positive and negative set then both and must hold, and therefore,
Hahn decomposition
The Hahn decomposition theorem states that for every measurable space with a signed measure there is a partition of into a positive and a negative set; such a partition is unique up to -null sets, and is called a Hahn decomposition of the signed measure
Given a Hahn decomposition of it is easy to show that is a positive set if and only if differs from a subset of by a -null set; equivalently, if is -null. The same is true for negative sets, if is used instead of
See also
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https://en.wikipedia.org/wiki/Chien%20search
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In abstract algebra, the Chien search, named after Robert Tienwen Chien, is a fast algorithm for determining roots of polynomials defined over a finite field. Chien search is commonly used to find the roots of error-locator polynomials encountered in decoding Reed-Solomon codes and BCH codes.
Algorithm
The problem is to find the roots of the polynomial (over the finite field ):
The roots may be found using brute force: there are a finite number of , so the polynomial can be evaluated for each element . If the polynomial evaluates to zero, then that element is a root.
For the trivial case , only the coefficient need be tested for zero. Below, the only concern will be for non-zero .
A straightforward evaluation of the polynomial involves general multiplications and additions. A more efficient scheme would use Horner's method for general multiplications and additions. Both of these approaches may evaluate the elements of the finite field in any order.
Chien search improves upon the above by selecting a specific order for the non-zero elements. In particular, the finite field has a (constant) generator element . Chien tests the elements in the generator's order . Consequently, Chien search needs only multiplications by constants and additions. The multiplications by constants are less complex than general multiplications.
The Chien search is based on two observations:
Each non-zero may be expressed as for some , where is a primitive element of , is the power number of primitive element . Thus the powers for cover the entire field (excluding the zero element).
The following relationship exists:
In other words, we may define each as the sum of a set of terms , from which the next set of coefficients may be derived thus:
In this way, we may start at with , and iterate through each value of up to . If at any stage the resultant summation is zero, i.e.
then also, so is a root. In this way, we check every element in the field.
When imple
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https://en.wikipedia.org/wiki/Schizophyte
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Schizophyte was a botanical classification proposed by Ferdinand Cohn to describe the class of primitive "plants" that reproduce solely by fission. It has been considered synonymous with the Protophyta of Sachs and the Monera of Haeckel. In modern taxonomy, it is equivalent with the concept of prokaryotes, single-celled microorganisms with no nucleus or other membrane-bound organelles, now divided into the domains Bacteria and Archaea.
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https://en.wikipedia.org/wiki/Automata-based%20programming
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Automata-based programming is a programming paradigm in which the program or part of it is thought of as a model of a finite-state machine (FSM) or any other (often more complicated) formal automaton (see automata theory). Sometimes a potentially infinite set of possible states is introduced, and such a set can have a complicated structure, not just an enumeration.
Finite-state machine-based programming is generally the same, but, formally speaking, does not cover all possible variants, as FSM stands for finite-state machine, and automata-based programming does not necessarily employ FSMs in the strict sense.
The following properties are key indicators for automata-based programming:
The time period of the program's execution is clearly separated down to the automaton steps. Each step is effectively an execution of a code section (same for all the steps) which has a single entry point. That section might be divided down to subsections to be executed depending on different states, although this is not necessary.
Any communication between the automaton steps is only possible via the explicitly noted set of variables named the automaton state. Between any two steps, the program cannot have implicit components of its state, such as local variables' values, return addresses, the current instruction pointer, etc. That is, the state of the whole program, taken at any two moments of entering an automaton step, can only differ in the values of the variables being considered as the automaton state.
The whole execution of the automata-based code is a cycle of the automaton steps.
Another reason for using the notion of automata-based programming is that the programmer's style of thinking about the program in this technique is very similar to the style of thinking used to solve mathematical tasks using Turing machines, Markov algorithms, etc.
Example
Task
Consider the task of reading a text from standard input line-by-line and writing the first word of each line to stan
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https://en.wikipedia.org/wiki/Goleo%20and%20Pille
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Goleo VI, commonly known as Goleo, and Pille, were the official mascots for the 2006 FIFA World Cup in Germany. Goleo takes the form of a lion, and is never found far from his sidekick, Pille, a talking football.
Goleo is clad in a white football shirt with black collar and sleeve rims, similar to those worn by the German national team between the 1950s and 1970s, and is trouserless. He wears a uniform with the number 06 (short for 2006, the World Cup year he was the mascot), and has his name written above it on the back of his shirt. The Goleo costume was manufactured by The Jim Henson Company, at a cost of around €250,000. The word Pille, meaning "pill" in standard German, is otherwise a common German sports jargon for a football. Goleo was unveiled as the World Cup mascot on November 13, 2004, during the German television program Wetten, dass..?, presented by Pelé and Franz Beckenbauer.
On May 16, 2006, the German licence holder to produce Goleo, Bavarian toy company NICI, filed for bankruptcy. One apparent reason could be very high licence fees of around €28 million. Other sources, however, quote much lower licence fees of €3.5 million.
Reception
The choice of a lion was criticized for not being a German animal, but rather the emblem of historical rivals England and the Netherlands. Renowned designer Erik Spiekermann suggested that the mascot should have been an eagle (which appears on Germany's coat of arms) or even a squirrel as a symbol of the nation of frugality in his opinion. Criticism has also been raised of the fact that Goleo does not wear any trousers.
Music appearances
"Love Generation"
He was also featured in the European version of music video for Bob Sinclar's song "Love Generation", which was released in Germany on December 9, 2005, the day of the draw of the World Cup.
"Dance!"
A computer animated Goleo also appeared in music videos for Lumidee's "Dance!" released in Spring 2006, just in time for the opening ceremonies for the World Cup.
"
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https://en.wikipedia.org/wiki/Resolvent%20formalism
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In mathematics, the resolvent formalism is a technique for applying concepts from complex analysis to the study of the spectrum of operators on Banach spaces and more general spaces. Formal justification for the manipulations can be found in the framework of holomorphic functional calculus.
The resolvent captures the spectral properties of an operator in the analytic structure of the functional. Given an operator , the resolvent may be defined as
Among other uses, the resolvent may be used to solve the inhomogeneous Fredholm integral equations; a commonly used approach is a series solution, the Liouville–Neumann series.
The resolvent of can be used to directly obtain information about the spectral decomposition
of . For example, suppose is an isolated eigenvalue in the
spectrum of . That is, suppose there exists a simple closed curve
in the complex plane that separates from the rest of the spectrum of .
Then the residue
defines a projection operator onto the eigenspace of .
The Hille–Yosida theorem relates the resolvent through a Laplace transform to an integral over the one-parameter group of transformations generated by . Thus, for example, if is a Hermitian, then is a one-parameter group of unitary operators. Whenever , the resolvent of A at z can be expressed as the Laplace transform
where the integral is taken along the ray .
History
The first major use of the resolvent operator as a series in (cf. Liouville–Neumann series) was by Ivar Fredholm, in a landmark 1903 paper in Acta Mathematica that helped establish modern operator theory.
The name resolvent was given by David Hilbert.
Resolvent identity
For all in , the resolvent set of an operator , we have that the first resolvent identity (also called Hilbert's identity) holds:
(Note that Dunford and Schwartz, cited, define the resolvent as , instead, so that the formula above differs in sign from theirs.)
The second resolvent identity is a generalization of the first reso
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https://en.wikipedia.org/wiki/Endoluminal%20capsule%20monitoring
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Endoluminal capsule monitoring is a non-invasive medical diagnostic procedure which uses a miniaturized wireless radio transmitter embedded into an ingestible water-tight capsule. The patient ingests the capsule and while it transits through the gastrointestinal system, it sends signals to the outside, which are captured by a radio receiver, processed, displayed and stored in a computer.
According to the type or type(s) of biomedical sensors which are built into the capsule, several physiological parameters can be measured and transmitted by the capsule:
intraluminal pH in the esophagus, stomach and duodenum
intestinal motility
intraluminal pressure
Other
Modern capsules, called video pills or endoscopic capsules can also transmit endoscopic images from a miniature video camera.
The system is normally used for research purposes or for diagnosing long term changes in gastrointestinal physiological parameters. The capsule is recovered in the feces, sterilized and can be used again.
Medical tests
Medical technology
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https://en.wikipedia.org/wiki/Nonsense-mediated%20decay
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Nonsense-mediated mRNA decay (NMD) is a surveillance pathway that exists in all eukaryotes. Its main function is to reduce errors in gene expression by eliminating mRNA transcripts that contain premature stop codons. Translation of these aberrant mRNAs could, in some cases, lead to deleterious gain-of-function or dominant-negative activity of the resulting proteins.
NMD was first described in human cells and in yeast almost simultaneously in 1979. This suggested broad phylogenetic conservation and an important biological role of this intriguing mechanism. NMD was discovered when it was realized that cells often contain unexpectedly low concentrations of mRNAs that are transcribed from alleles carrying nonsense mutations. Nonsense mutations code for a premature stop codon which causes the protein to be shortened. The truncated protein may or may not be functional, depending on the severity of what is not translated. In human genetics, NMD has the possibility to not only limit the translation of abnormal proteins, but it can occasionally cause detrimental effects in specific genetic mutations.
NMD functions to regulate numerous biological functions in a diverse range of cells, including the synaptic plasticity of neurons which may shape adult behavior.
Pathway
While many of the proteins involved in NMD are not conserved between species, in Saccharomyces cerevisiae (yeast), there are three main factors in NMD: UPF1, UPF2 and UPF3 (UPF3A and UPF3B in humans), that make up the conserved core of the NMD pathway. All three of these factors are trans-acting elements called up-frameshift (UPF) proteins. In mammals, UPF2 and UPF3 are part of the exon-exon junction complex (EJC) bound to mRNA after splicing along with other proteins, eIF4AIII, MLN51, and the Y14/MAGOH heterodimer, which also function in NMD. UPF1 phosphorylation is controlled by the proteins SMG-1, SMG-5, SMG-6 and SMG-7.
The process of detecting aberrant transcripts occurs during translation of the mRNA
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https://en.wikipedia.org/wiki/CRAC-II
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CRAC-II is both a computer code (titled Calculation of Reactor Accident Consequences) and the 1982 report of the simulation results performed by Sandia National Laboratories for the Nuclear Regulatory Commission. The report is sometimes referred to as the CRAC-II report because it is the computer program used in the calculations, but the report is also known as the 1982 Sandia Siting Study or as NUREG/CR-2239. The computer program MACCS2 has since replaced CRAC-II for the consequences of radioactive release.
CRAC-II has been declared to be obsolete and will be replaced by the State-of-the-Art Reactor Consequence Analyses study.
The CRAC-II simulations calculated the possible consequences of a worst-case accident under worst-case conditions (a so-called "class-9 accident") for several different U.S. nuclear power plants. In the Sandia Siting Study, the Indian Point Energy Center was calculated to have the largest possible consequences for an SST1 (spectrum of source terms) release, with estimated maximum possible casualty numbers of around 50,000 deaths, 150,000 injuries, and property damage of $274 Billion to $314 Billion (based on figures at the time of the report in 1982). The Sandia Siting Study ,however, is commonly misused as a risk analysis, which it is not. It is a sensitivity analysis of different amounts of radioactive releases and an SST1 release is now generally considered not a credible accident (see below).
Another significant report is the 1991 NUREG-1150 calculations, which is a more-rigorous risk assessment of five U.S. Nuclear Power Plants.
Followup study
As the NRC was preparing NUREG-1437, Supplement 56, "Generic Environmental Impact Statement for License Renewal of Nuclear Plants Supplement 56 Regarding Fermi Nuclear Power Plant", it solicited comments on the proposed report. In response to comments specifically mentioning the CRAC-II study, the NRC wrote:
"The U.S. Nuclear Regulatory Commission has devoted considerable research resources,
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https://en.wikipedia.org/wiki/Dependency%20need
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Dependency need is "the vital, originally infantile needs for mothering, love, affection, shelter, protection, security, food, and warmth." (Segen, 1992)
A dependency need is thought to be characterized by two components: (1) It is a real need of an organism, something that must be present in order for the organism to be able to thrive, (2) It is something that an individual cannot provide for him or herself. It is well known that infants have many dependency needs; some of these needs are obvious, others have only come to the attention of researchers as the result of epidemiological studies. The more obvious needs of infants include: adequate feeding, adequate watering, adequate cleaning, adequate shelter, and more specifically, keeping the infant's body temperature within the narrow range of normalcy.
On the other hand, it was not well known until the middle of the 20th century that infants also required the presence of warmth and affection, known as "maternal warmth". The greatest number of dependency needs seem to be encompassed in infancy, but dependency needs begin to change and decrease with age and maturity. This marked decrease in dependency needs as an individual gets older can be largely attributed to the notion that, as an individual gets older, he or she becomes capable of providing these things for him or herself. To some extent, these needs remain present even into adulthood. Even as adults, people have certain universal dependency needs that remain constant throughout the lifespan that they are not able to provide for themselves; these include: the need to belong, need for affection, as well as the need for emotional support. These needs can usually be met by partnership, in which both partners get used to depending on one another. If adults lack partnership, their needs can usually be met by family and/or friend relationships.
Importance
Dependency need is an important psychological concept, encompassing the fields of psychological, evolutiona
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https://en.wikipedia.org/wiki/Kontorovich%E2%80%93Lebedev%20transform
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In mathematics, the Kontorovich–Lebedev transform is an integral transform which uses a Macdonald function (modified Bessel function of the second kind) with imaginary index as its kernel. Unlike other Bessel function transforms, such as the Hankel transform, this transform involves integrating over the index of the function rather than its argument.
The transform of a function ƒ(x) and its inverse (provided they exist) are given below:
Laguerre previously studied a similar transform regarding Laguerre function as:
Erdélyi et al., for instance, contains a short list of Kontorovich–Lebedev transforms as well references to the original work of Kontorovich and Lebedev in the late 1930s. This transform is mostly used in solving the Laplace equation in cylindrical coordinates for wedge shaped domains by the method of separation of variables.
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https://en.wikipedia.org/wiki/Mizuna
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, kyouna (京菜), Japanese mustard greens, or spider mustard, is a cultivar of Brassica rapa var. niposinica.
Description and use
Possessing dark green, serrated leaves, mizuna is described as having, when raw, a "piquant, mild peppery flavor...slightly spicy, but less so than arugula." It is also used in stir-fries, soups, and nabemono (Japanese hot pots).
Varieties
In addition to the term mizuna (and its alternates) being applied to at least two different species of Brassica, horticulturalists have defined and named a number of varieties. For example, a resource provided by Cornell University and the United States Department of Agriculture lists sixteen varieties including "Early Mizuna", "Kyona Mizuna", "Komatsuna Mizuna", "Vitamin Green Mizuna", "Kyoto Mizuna", "Happy Rich Mizuna", "Summer Fest Mizuna", "Tokyo Early Mizuna", "Mibuna Mizuna", "Red Komatsuna Mizuna", "Waido Mizuna" and "Purple Mizuna". There is also a variety known as pink mizuna.
Cultivation
Mizuna has been cultivated in Japan since ancient times. Mizuna was successfully grown in the International Space Station in 2019. It grows in hardiness zones 4 to 9, prefers full sun or partial shade, well-drained soil and a pH of 6.5-7.0. It can be grown as a microgreen, sowing every 3 cm, or for its leaves with a 20 cm spacing. It is produced by more than 30 countries around the world, but China, Japan, South Korea, India and United States account for 70% of global production.
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https://en.wikipedia.org/wiki/Normalization%20model
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The normalization model is an influential model of responses of neurons in primary visual cortex. David Heeger developed the model in the early 1990s, and later refined it together with Matteo Carandini and J. Anthony Movshon. The model involves a divisive stage. In the numerator is the output of the classical receptive field. In the denominator, a constant plus a measure of local stimulus contrast. Although the normalization model was initially developed to explain responses in the primary visual cortex, normalization is now thought to operate throughout the visual system, and in many other sensory modalities and brain regions, including the representation of odors in the olfactory bulb, the modulatory effects of visual attention, the encoding of value, and the integration of multisensory information. It has also been observed at subthreshold potentials in the hippocampus. Its presence in such a diversity of neural systems in multiple species, from invertebrates to mammals, suggests that normalization serves as a canonical neural computation. Divisive normalization reduces the redundancy in natural stimulus statistics and is sometimes viewed as an implementation of the efficient coding principle. Formally, divisive normalization is an information-maximizing code for stimuli following a multivariate Pareto distribution.
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https://en.wikipedia.org/wiki/Smart%20environment
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Smart environments link computers and other smart devices to everyday settings and tasks. Smart environments include smart homes, smart cities and smart manufacturing.
Introduction
Smart environments are an extension of pervasive computing. According to Mark Weiser, pervasive computing promotes the idea of a world that is connected to sensors and computers. These sensors and computers are integrated with everyday objects in peoples' lives and are connected through networks.
Definition
Cook and Das define smart environment as "a small world where different kinds of smart device are continuously working to make inhabitants' lives more comfortable." Smart environments aim to satisfy the experience of individuals from every environment, by replacing the hazardous work, physical labor, and repetitive tasks with automated agents.
Poslad
differentiates three different kinds of smart environments for systems, services and devices: virtual (or distributed) computing environments, physical environments and human environments, or a hybrid combination of these:
Virtual computing environments enable smart devices to access pertinent services anywhere and anytime.
Physical environments may be embedded with a variety of smart devices of different types including tags, sensors and controllers and have different form factors ranging from nano- to micro- to macro-sized.
Human environments: humans, either individually or collectively, inherently form a smart environment for devices. However, humans may themselves be accompanied by smart devices such as mobile phones, use surface-mounted devices (wearable computing) and contain embedded devices (e.g., pacemakers to maintain a healthy heart operation or AR contact lenses).
Features
Smart environments are broadly classified to have the following features
Remote control of devices, like power line communication systems to control devices.
Device Communication, using middleware, and Wireless communication to form a picture of con
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https://en.wikipedia.org/wiki/Magnetotactic%20bacteria
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Magnetotactic bacteria (or MTB) are a polyphyletic group of bacteria that orient themselves along the magnetic field lines of Earth's magnetic field. Discovered in 1963 by Salvatore Bellini and rediscovered in 1975 by Richard Blakemore, this alignment is believed to aid these organisms in reaching regions of optimal oxygen concentration. To perform this task, these bacteria have organelles called magnetosomes that contain magnetic crystals. The biological phenomenon of microorganisms tending to move in response to the environment's magnetic characteristics is known as magnetotaxis. However, this term is misleading in that every other application of the term taxis involves a stimulus-response mechanism. In contrast to the magnetoreception of animals, the bacteria contain fixed magnets that force the bacteria into alignment—even dead cells are dragged into alignment, just like a compass needle.
Introduction
The first description of magnetotactic bacteria was in 1963 by Salvatore Bellini of the University of Pavia. While observing bog sediments under his microscope, Bellini noticed a group of bacteria that evidently oriented themselves in a unique direction. He realized these microorganisms moved according to the direction of the North Pole, and hence called them "magnetosensitive bacteria". The publications were academic (peer-reviewed by the Istituto di Microbiologias editorial committee under responsibility of the Institute's Director Prof. L. Bianchi, as usual in European universities at the time) and communicated in Italian with English, French and German short summaries in the official journal of a well-known institution, yet unexplainedly seem to have attracted little attention until they were brought to the attention of Richard Frankel in 2007. Frankel translated them into English and the translations were published in the Chinese Journal of Oceanography and Limnology.
Richard Blakemore, then a microbiology graduate student at the University of Massachus
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https://en.wikipedia.org/wiki/List%20of%20chemical%20warfare%20agents
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A chemical weapon agent (CWA), or chemical warfare agent, is a chemical substance whose toxic properties are meant to kill, injure or incapacitate human beings. About 70 different chemicals have been used or stockpiled as chemical weapon agents during the 20th century. These agents may be in liquid, gas or solid form.
In general, chemical weapon agents are organized into several categories (according to the physiological manner in which they affect the human body). They may also be divided by tactical purpose or chemical structure. The names and number of categories may vary slightly from source to source, but, in general, the different types of chemical warfare agents are listed below.
Harassing agents
These are substances that are not intended to kill or injure. They are often referred to as Riot Control Agents (RCAs) and may be used by civilian police forces against criminals and rioters, or in the military for training purposes. These agents also have tactical utility to force combatants out of concealed or covered positions for conventional engagement, and preventing combatants from occupying contaminated terrain or operating weapons. In general, harassing agents are sensory irritants that have fleeting concentration dependent effects that resolve within minutes after removal. Casualty effects are not anticipated to exceed 24-hours nor require medical attention.
Tear agents
These sensory irritants produce immediate pain to the eyes and irritate mucous membranes (aka lachrymatory agent or lachrymator).
Benzyl chloride
Benzyl bromide
Bromoacetone (BA)
Bromobenzylcyanide (CA)
Bromomethyl ethyl ketone
Capsaicin (OC)
Chloracetophenone (MACE; CN)
Chloromethyl chloroformate
Dibenzoxazepine (CR)
Ethyl iodoacetate
Ortho-chlorobenzylidene malononitrile (Super tear gas; CS)
Trichloromethyl chloroformate
Xylyl bromide
Vomiting agents
These sensory irritants are also termed sternators or nose irritants. They irritate the mucous membranes to produce c
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https://en.wikipedia.org/wiki/Barrier%20function
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In constrained optimization, a field of mathematics, a barrier function is a continuous function whose value on a point increases to infinity as the point approaches the boundary of the feasible region of an optimization problem. Such functions are used to replace inequality constraints by a penalizing term in the objective function that is easier to handle.
The two most common types of barrier functions are inverse barrier functions and logarithmic barrier functions. Resumption of interest in logarithmic barrier functions was motivated by their connection with primal-dual interior point methods.
Motivation
Consider the following constrained optimization problem:
minimize
subject to
where is some constant. If one wishes to remove the inequality constraint, the problem can be re-formulated as
minimize ,
where if , and zero otherwise.
This problem is equivalent to the first. It gets rid of the inequality, but introduces the issue that the penalty function , and therefore the objective function , is discontinuous, preventing the use of calculus to solve it.
A barrier function, now, is a continuous approximation to that tends to infinity as approaches from above. Using such a function, a new optimization problem is formulated, viz.
minimize
where is a free parameter. This problem is not equivalent to the original, but as approaches zero, it becomes an ever-better approximation.
Logarithmic barrier function
For logarithmic barrier functions, is defined as when and otherwise (in 1 dimension. See below for a definition in higher dimensions). This essentially relies on the fact that tends to negative infinity as tends to 0.
This introduces a gradient to the function being optimized which favors less extreme values of (in this case values lower than ), while having relatively low impact on the function away from these extremes.
Logarithmic barrier functions may be favored over less computationally expensive inverse barrier functions depending
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https://en.wikipedia.org/wiki/History%20of%20the%20Hindu%E2%80%93Arabic%20numeral%20system
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The Hindu–Arabic numeral system is a decimal place-value numeral system that uses a zero glyph as in "205".
Its glyphs are descended from the Indian Brahmi numerals. The full system emerged by the 8th to 9th centuries, and is first described outside India in Al-Khwarizmi's On the Calculation with Hindu Numerals (ca. 825), and second Al-Kindi's four-volume work On the Use of the Indian Numerals (ca. 830). Today the name Hindu–Arabic numerals is usually used.
Decimal system
Historians trace modern numerals in most languages to the Brahmi numerals, which were in use around the middle of the 3rd century BC. The place value system, however, developed later. The Brahmi numerals have been found in inscriptions in caves and on coins in regions near Pune, Maharashtra and Uttar Pradesh in India. These numerals (with slight variations) were in use up to the 4th century.
During the Gupta period (early 4th century to the late 6th century), the Gupta numerals developed from the Brahmi numerals and were spread over large areas by the Gupta empire as they conquered territory. Beginning around 7th century, the Gupta numerals developed into the Nagari numerals.
Development in India
During the Vedic period (1500–500 BCE), motivated by geometric construction of the fire altars and astronomy, the use of a numerical system and of basic mathematical operations developed in northern India. Hindu cosmology required the mastery of very large numbers such as the kalpa (the lifetime of the universe) said to be 4,320,000,000 years and the "orbit of the heaven" said to be 18,712,069,200,000,000 yojanas. Numbers were expressed using a "named place-value notation", using names for the powers of 10, like dasa, shatha, sahasra, ayuta, niyuta, prayuta, arbuda, nyarbuda, samudra, madhya, anta, parardha etc., the last of these being the name for a trillion (1012). For example, the number 26,432 was expressed as "2 ayuta, 6 sahasra, 4 shatha, 3 dasa, 2." In the Buddhist text Lalitavistara, the
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https://en.wikipedia.org/wiki/Video%20display%20controller
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A video display controller or VDC (also called a display engine or display interface) is an integrated circuit which is the main component in a video-signal generator, a device responsible for the production of a TV video signal in a computing or game system. Some VDCs also generate an audio signal, but that is not their main function.
VDCs were used in the home computers of the 1980s and also in some early video picture systems.
The VDC is the main component of the video signal generator logic, responsible for generating the timing of video signals such as the horizontal and vertical synchronization signals and the blanking interval signal. Sometimes other supporting chips were necessary to build a complete system, such as RAM to hold pixel data, ROM to hold character fonts, or some discrete logic such as shift registers.
Most often the VDC chip is completely integrated in the logic of the main computer system, (its video RAM appears in the memory map of the main CPU), but sometimes it functions as a coprocessor that can manipulate the video RAM contents independently.
Video display controller vs. graphics processing unit
The difference between a display controller, a graphics accelerator, and a video compression/decompression IC is huge, but, since all of this logic is usually found on the chip of a graphics processing unit and is usually not available separately to the end-customer, there is often much confusion about these very different functional blocks.
GPUs with hardware acceleration started appearing during the 1990s. VDCs often had special hardware for the creation of "sprites", a function that in more modern VDP chips is done with the "Bit Blitter" using the "Bit blit" function.
One example of a typical video display processor is the "VDP2 32-bit background and scroll plane video display processor" of the Sega Saturn.
Another example is the Lisa (AGA) chip that was used for the improved graphics of the later generation Amiga computers.
That said, i
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https://en.wikipedia.org/wiki/Variation%20ratio
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The variation ratio is a simple measure of statistical dispersion in nominal distributions; it is the simplest measure of qualitative variation.
It is defined as the proportion of cases which are not in the mode category:
where fm is the frequency (number of cases) of the mode, and N is the total number of cases. While a simple measure, it is notable in that some texts and guides suggest or imply that the dispersion of nominal measurements cannot be ascertained. It is defined for instance by .
Just as with the range or standard deviation, the larger the variation ratio, the more differentiated or dispersed the data are; and the smaller the variation ratio, the more concentrated and similar the data are.
An example
A group which is 55% female and 45% male has a proportion of 0.55 females (the mode is 0.55), therefore its variation ratio is
Similarly, in a group of 100 people where 60 people like beer 25 people like wine and the rest (15) prefer cocktails, the variation ratio is
See also
Qualitative variation, for a number of other measures of dispersion in nominal variables
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https://en.wikipedia.org/wiki/Mocha%20%28decompiler%29
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Mocha is a Java decompiler, which allows programmers to translate a program's bytecode into source code.
A beta version of Mocha was released in 1996, by Dutch developer Hanpeter van Vliet, alongside an obfuscator named Crema. A controversy erupted and he temporarily withdrew Mocha from public distribution. As of 2009 the program is still available for distribution, and may be used freely as long as it is not modified. Borland's JBuilder includes a decompiler based on Mocha. Van Vliet's websites went offline as he died of cancer on December 31, 1996 at the age of 34.
See also
JAD (JAva Decompiler)
JD
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https://en.wikipedia.org/wiki/Vanilla%20sugar
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Vanilla sugar (German: Vanillezucker, Polish: Cukier waniliowy, Hungarian: Vaníliás cukor, Swedish: Vaniljsocker, Macedonian: Ванилин шеќер) is a commonly used ingredient in many European desserts.
Vanilla sugar is made of sugar and vanilla beans, or sugar mixed with vanilla extract (in a proportion of two cups of sugar for one teaspoon of extract).
Pre-packaged vanilla sugar can be costly and difficult to obtain outside Europe but can be made at home. Sometimes it can be replaced with vanilla extract, where one teaspoon equals one package. However, when it is needed as a topping, vanilla extract is unsuitable.
Vanilla sugar can be prepared by combining 400 g (2 cups) of white sugar with the scraped seeds of one vanilla bean. It can also be made by adding 1 to 2 whole vanilla beans to an airtight jar with 200 to 400 g (1 to 2 cups) of white sugar, and aging the mixture for two weeks; the sugar can be replaced as it is used.
Cheaper vanilla sugar is also available, made only from sugar and vanillin.
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https://en.wikipedia.org/wiki/Television%20interference
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Television interference (TVI) is a particular case of electromagnetic interference which affects television reception. Many natural and man-made phenomena can disrupt the reception of television signals. These include naturally occurring and artificial spark discharges, and effects due to the operation of radio transmitters.
Analog television broadcasts display different effects due to different kinds of interference. Digital television reception generally gives a good quality picture until the interference is so large that it can no longer be eliminated by the error checking systems in the receiver, at which point the video display becomes pixelated, distorts, or goes blank.
Co-channel and multipath (ghost)
During unusual atmospheric conditions, a distant station normally undectable at a particular location may provide a much stronger signal than usual. The analog television picture may display the sum of the two signals, producing an image from the strong local signal with traces or "ghosts" from the distant, weaker signal. Television broadcast stations are located and assigned to channels so that such events are rare. Readjustment of the receiving antenna may allow more of the distant signal to be rejected, improving image quality.
A local signal may travel by more than one path from the transmitter to receiving antenna. "Multipath" reception is visible as multiple impressions of the same image, slightly shifted along the width of the screen due to the varying transmission path. Some multipath reception is momentary due to road vehicles or aircraft passing; other multipath problems may persist due to reflection off tall buildings or other landscape features. Strong multipath can cause the analog picture to "tear" or momentarily lose synchronization, causing it to roll or flip.
Static electricity and sparks
The sparks generated by static electricity can generate interference.
Many systems where radio frequency interface is caused by sparking can be modele
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https://en.wikipedia.org/wiki/Pierre%20Gagnaire
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Pierre Gagnaire (born 9 April 1950 in Apinac, Loire) is a French chef, and the head chef and owner of the eponymous Pierre Gagnaire restaurant at 6 rue Balzac in Paris (in the 8th arrondissement). Gagnaire is an iconoclastic chef at the forefront of the fusion cuisine movement. Beginning his career in St. Etienne where he won three Michelin Stars, Gagnaire tore at the conventions of classic French cooking by introducing jarring juxtapositions of flavours, tastes, textures, and ingredients.
On his website, Gagnaire gives his mission statement as the wish to run a restaurant which is 'facing tomorrow but respectful of yesterday' ("tourné vers demain mais soucieux d'hier").
In Europe
The restaurant, Pierre Gagnaire, specializes in modern French cuisine and has garnered three Michelin stars. Gagnaire is also head chef of Sketch in London. In 2005, both restaurants were ranked in the S.Pellegrino World's 50 Best Restaurants by industry magazine Restaurant, with Pierre Gagnaire ranking third for three consecutive years (2006, 2007, and 2008).
In the United States
In December 2009, Gagnaire made his United States debut with Twist, a new restaurant at the Mandarin Oriental in Las Vegas, which has since received a Forbes Five-Star Award but has since closed.
Media appearances
Pierre Gagnaire has made appearances on Fuji TV's Iron Chef. He represented France in the 1995 Iron Chef World Cup in Tokyo, with the other chefs chosen being Italy's Gianfranco Vissani and Hong Kong's Xu Cheng as well as Iron Chef Japanese Rokusaburo Michiba representing Japan. He also appeared in the "France Battle Special" at Château de Brissac, where he battled Iron Chef French Hiroyuki Sakai.
Awards
In 2015, Gagnaire won a Best Chef in the World award.
Restaurants
Paris, Pierre Gagnaire, 1996–
Paris, Gaya rive gauche par Pierre Gagnaire, 2005–
Berlin, Les Solistes by Pierre Gagnaire, 2013–2016 (closed)
Bordeaux, La Grande Maison
Châtelaillon, Gaya Cuisine De Bords de Mer
Courchevel, Pie
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https://en.wikipedia.org/wiki/%27t%20Hooft%20loop
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In quantum field theory, the 't Hooft loop is a magnetic analogue of the Wilson loop for which spatial loops give rise to thin loops of magnetic flux associated with magnetic vortices. They play the role of a disorder parameter for the Higgs phase in pure gauge theory. Consistency conditions between electric and magnetic charges limit the possible 't Hooft loops that can be used, similarly to the way that the Dirac quantization condition limits the set of allowed magnetic monopoles. They were first introduced by Gerard 't Hooft in 1978 in the context of possible phases that gauge theories admit.
Definition
There are a number of ways to define 't Hooft lines and loops. For timelike curves they are equivalent to the gauge configuration arising from the worldline traced out by a magnetic monopole. These are singular gauge field configurations on the line such that their spatial slice have a magnetic field whose form approaches that of a magnetic monopole
where in Yang–Mills theory is the generally Lie algebra valued object specifying the magnetic charge. 't Hooft lines can also be inserted in the path integal by requiring that the gauge field measure can only run over configurations whose magnetic field takes the above form.
More generally, the 't Hooft loop can be defined as the operator whose effect is equivalent to performing a modified gauge transformations that is singular on the loop in such a way that any other loop parametrized by with a winding number around satisfies
These modified gauge transformations are not true gauge transformations as they do not leave the action invariant. For temporal loops they create the aforementioned field configurations while for spatial loops they instead create loops of color magnetic flux, referred to as center vortices. By constructing such gauge transformations, an explicit form for the 't Hooft loop can be derived by introducing the Yang–Mills conjugate momentum operator
If the loop encloses a surface , then
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https://en.wikipedia.org/wiki/Order%20operator
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In quantum field theory, an order operator or an order field is a quantum field version of Landau's order parameter whose expectation value characterizes phase transitions. There exists a dual version of it, the disorder operator or disorder field, whose expectation value characterizes a phase transition by indicating the prolific presence of defect or vortex lines in an ordered phase.
The disorder operator is an operator that creates a discontinuity of the ordinary order operators or a monodromy for their values. For example, a 't Hooft operator is a disorder operator. So is the Jordan–Wigner transformation. The concept of a disorder observable was first introduced in the context of 2D Ising spin lattices, where a phase transition between spin-aligned (magnetized) and disordered phases happens at some temperature.
Books
Kleinert, Hagen, Gauge Fields in Condensed Matter, Vol. I, " SUPERFLOW AND VORTEX LINES", pp. 1–742, Vol. II, "STRESSES AND DEFECTS", pp. 743–1456, World Scientific (Singapore, 1989); Paperback (also available online: Vol. I and Vol. II)
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https://en.wikipedia.org/wiki/Estragole
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Estragole (p-allylanisole, methyl chavicol) is a phenylpropene, a natural organic compound. Its chemical structure consists of a benzene ring substituted with a methoxy group and an allyl group. It is an isomer of anethole, differing with respect to the location of the double bond. It is a colorless liquid, although impure samples can appear yellow. It is a component of various trees and plants, including turpentine (pine oil), anise, fennel, bay, tarragon, and basil. It is used in the preparation of fragrances.
The compound is named for estragon, the French name of tarragon.
Production
Hundreds of tonnes of basil oil are produced annually by steam distillation of Ocimum basilicum (common basil). This oil is mainly estragole but also contains substantial amounts of linalool.
Estragole is the primary constituent of essential oil of tarragon (comprising 60–75%). It is also present in pine oil, turpentine, fennel, anise (2%), Clausena anisata and Syzygium anisatum.
Estragole is used in perfumes and is restricted in flavours as a biologically active principle: it can only be present in a flavour by using an essential oil. Upon treatment with potassium hydroxide, estragole converts to anethole. A known use of estragole is in the synthesis of magnolol.
Safety
Estragole is suspected to be carcinogenic and genotoxic, as is indicated by a report of the European Union Committee on Herbal Medicinal Products. Several studies have clearly established that the profiles of metabolism, metabolic activation, and covalent binding are dose dependent and that the relative importance diminishes markedly at low levels of exposure (that is, these events are not linear with respect to dose). In particular, rodent studies show that these events are minimal probably in the dose range of 1–10 mg/kg body weight, which is approximately 100 to 1,000 times the anticipated human exposure to this substance. For these reasons it is concluded that the present exposure to estragole resulting f
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https://en.wikipedia.org/wiki/Slime%20%28Dragon%20Quest%29
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are a fictional species of monster in the Dragon Quest role-playing video game franchise. Originally inspired by the game Wizardry to be a weak and common enemy for the 1986 video game Dragon Quest, Slimes have appeared in almost every Dragon Quest game since. Their popularity led to the appearance of many varieties of Slimes, including boss characters, friendly allies, and even emerging as the protagonist of the Rocket Slime video game series. Slimes have also appeared in other video game properties, including Nintendo's Mario and Super Smash Bros. series of crossover fighting games.
Their friendliness, limited power, and appealing form have caused the Slime to become a popular character and the mascot of the Dragon Quest series. It have been also placed on a multitude of different kinds of merchandise.
Concept and design
According to Yuji Horii, the creator of Dragon Quest, the inspiration for the Slimes came from a role-playing game series called Wizardry. Horii said that when it was originally conceived, the Slime was "a pile of goo", but Akira Toriyama's design came back as a tear-drop which they considered "perfect".
There are many different types of Slimes found throughout the Dragon Quest and Rocket Slime series. These include Slimes in different colors; She Slimes which are orange slimes that are slightly stronger then regular slimes and are despite their name, not always necessarily female; Bubble Slimes which look like pools of slime; Nautical Slimes that wear conch shells; the rare Metal Slimes which have high defense, give out large amounts of experience points, and tend to flee from battle; Healslimes which have tentacles; gem-shaped Slimes like the Emperor Slime; cube-shaped Box Slimes; and King Slimes, which are very large Slimes wearing crowns and come in various versions such as regular or metal.
In most appearances of Slimes, the creature plays an antagonist role, and occasionally appears as a boss. In some Dragon Quest titles, Slimes also ap
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https://en.wikipedia.org/wiki/Validator
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A validator is a computer program used to check the validity or syntactical correctness of a fragment of code or document. The term is commonly used in the context of validating HTML, CSS, and XML documents like RSS feeds, though it can be used for any defined format or language.
Accessibility validators are automated tools that are designed to verify compliance of a web page or a web site with respect to one or more accessibility guidelines (such as WCAG, Section 508 or those associated with national laws such as the Stanca Act).
See also
CSS HTML Validator for Windows
HTML Tidy
W3C Markup Validation Service
Well-formed element
XML validation
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https://en.wikipedia.org/wiki/Current%20divider
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In electronics, a current divider is a simple linear circuit that produces an output current (IX) that is a fraction of its input current (IT). Current division refers to the splitting of current between the branches of the divider. The currents in the various branches of such a circuit will always divide in such a way as to minimize the total energy expended.
The formula describing a current divider is similar in form to that for the voltage divider. However, the ratio describing current division places the impedance of the considered branches in the denominator, unlike voltage division, where the considered impedance is in the numerator. This is because in current dividers, total energy expended is minimized, resulting in currents that go through paths of least impedance, hence the inverse relationship with impedance. Comparatively, voltage divider is used to satisfy Kirchhoff's voltage law (KVL). The voltage around a loop must sum up to zero, so the voltage drops must be divided evenly in a direct relationship with the impedance.
To be specific, if two or more impedances are in parallel, the current that enters the combination will be split between them in inverse proportion to their impedances (according to Ohm's law). It also follows that if the impedances have the same value, the current is split equally.
Current divider
A general formula for the current IX in a resistor RX that is in parallel with a combination of other resistors of total resistance RT (see Figure 1) is
where IT is the total current entering the combined network of RX in parallel with RT. Notice that when RT is composed of a parallel combination of resistors, say R1, R2, ... etc., then the reciprocal of each resistor must be added to find the reciprocal of the total resistance RT:
General case
Although the resistive divider is most common, the current divider may be made of frequency-dependent impedances. In the general case:
and the current IX is given by
where ZT refers to the
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https://en.wikipedia.org/wiki/Thigmomorphogenesis
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Thigmomorphogenesis (from Ancient Greek θιγγάνω (thingánō) to touch, μορφή (morphê) shape, and γένεσις (génesis) creation) is the response by plants to mechanical sensation (touch) by altering their growth patterns. In the wild, these patterns can be evinced by wind, raindrops, and rubbing by passing animals.
Botanists have long known that plants grown in a greenhouse tend to be taller and more spindly than plants grown outside. M.J. Jaffe discovered in the 1970s that regular rubbing or bending of stems inhibits their elongation and stimulates their radial expansion, resulting in shorter, stockier plants.
Growth responses are caused by changes in gene expression. This is likely related to the calcium-binding protein calmodulin, suggesting Ca2+ involvement in mediating growth responses.
Thigmomorphogenesis has also been determined to be a form of phenotypic plasticity in plants, potentially inducing different adaptive and stress responses in a variety of species.
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https://en.wikipedia.org/wiki/CaBIG
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The cancer Biomedical Informatics Grid (caBIG) was a US government program to develop an open-source, open access information network called caGrid for secure data exchange on cancer research. The initiative was developed by the National Cancer Institute (part of the National Institutes of Health) and was maintained by the Center for Biomedical Informatics and Information Technology (CBIIT) and program managed by Booz Allen Hamilton. In 2011 a report on caBIG raised significant questions about effectiveness and oversight, and its budget and scope were significantly trimmed. In May 2012, the National Cancer Informatics Program (NCIP) was created as caBIG's successor program.
History
The National Cancer Institute (NCI) of the United States funded the cancer Biomedical Informatics Grid (caBIG) initiative in spring 2004, headed by Kenneth Buetow.
Its goal was to connect US biomedical cancer researchers using technology known as grid computing. The program, led by the Center for Bioinformatics and Information Technology (CBIIT), began with a 3-year pilot phase. The pilot phase concluded in March 2007, and a trial was announced.
Buetow promoted the program in 2008.
In addition to caGrid, the underlying infrastructure for data sharing among organizations, caBIG developed software tools, data sharing policies, and common standards and vocabularies to facilitate data sharing.
Software tools targeted:
Collection, analysis, and management of basic research data
Clinical trials management, from patient enrollment to adverse event reporting and analysis
Collection, annotation, sharing, and storage of medical imaging data
Biospecimen management
caBIG sought to provide foundational technology for an approach to biomedicine it called a “learning healthcare system.” This relies on the rapid exchange of information among all sectors of research and care, so that researchers and clinicians are able to collaboratively review and accurately incorporate the latest findings into their
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https://en.wikipedia.org/wiki/Parametric%20polymorphism
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In programming languages and type theory, parametric polymorphism allows a single piece of code to be given a "generic" type, using variables in place of actual types, and then instantiated with particular types as needed. Parametrically polymorphic functions and data types are sometimes called generic functions and generic datatypes, respectively, and they form the basis of generic programming.
Parametric polymorphism may be contrasted with ad hoc polymorphism. Parametrically polymorphic definitions are uniform: they behave identically regardless of the type they are instantiated at. In contrast, ad hoc polymorphic definitions are given a distinct definition for each type. Thus, ad hoc polymorphism can generally only support a limited number of such distinct types, since a separate implementation has to be provided for each type.
Basic definition
It is possible to write functions that do not depend on the types of their arguments. For example, the identity function simply returns its argument unmodified. This naturally gives rise to a family of potential types, such as , , , and so on. Parametric polymorphism allows to be given a single, most general type by introducing a universally quantified type variable:
The polymorphic definition can then be instantiated by substituting any concrete type for , yielding the full family of potential types.
The identity function is a particularly extreme example, but many other functions also benefit from parametric polymorphism. For example, an function that appends two lists does not inspect the elements of the list, only the list structure itself. Therefore, can be given a similar family of types, such as , , and so on, where denotes a list of elements of type . The most general type is therefore
which can be instantiated to any type in the family.
Parametrically polymorphic functions like and are said to be parameterized over an arbitrary type . Both and are parameterized over a single type, but functions ma
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https://en.wikipedia.org/wiki/Cribbing%20%28horse%29
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Cribbing is a form of stereotypy (equine oral stereotypic behaviour), otherwise known as wind sucking or crib-biting. Cribbing is considered to be an abnormal, compulsive behavior seen in some horses, and is often labelled a stable vice. The major factors that cause cribbing include stress, stable management, genetic and gastrointestinal irritability.
Cribbing was mentioned in the literature as early as 1578 and occurs in 2.4-8.3% of horses depending on breed and management.
A similar but unrelated behavior, wood-chewing or lignophagia, is another undesirable habit observed in horses, but it does not involve sucking in air; the horse simply gnaws on wood rails or boards as if they were food.
Description
Cribbing, or crib biting, involves a horse grasping a solid object such as the stall door or fence rail with its incisor teeth, arching its neck, and contracting the lower neck muscles to retract the larynx caudally. This movement is coincided with an in-rush of air through the crico-pharynx into the oesophagus producing the characteristic cribbing sound or grunt. Usually, air is not swallowed but returns to the pharynx. It is considered to be an abnormal, compulsive behavior or stereotypy, and often labelled as a stable vice.
Wind-sucking is a related behavior whereby the horse arches its neck and sucks air into the windpipe but does so without grasping an object. Wind-sucking is thought to form part of the mechanism of cribbing, rather than being defined as an entirely separate behavior.
Wood-chewing
A similar, but unrelated behavior, wood-chewing (lignophagia), is another undesirable behavior sometimes observed in horses. The horse gnaws on wood rails or boards as if they were food, but it does not involve sucking in air.
Prevalence and incidence
It is reported that 2.4–8.3% of horses in Europe and Canada are cribbers and that cribbing can occupy 15-65% of an individual horse's daily time budget. A postal survey in 2009 found that an average of 4.4% hor
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https://en.wikipedia.org/wiki/List%20of%20portable%20software
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For the purposes of this list, a portable application is software that can be used from portable storage devices such as USB flash drives, digital audio players, PDAs or external hard drives. To be considered for inclusion, an application must be executable on multiple computers from removable storage without installation, and without writing settings or data onto a computer's non-removable storage. This includes modified portable versions of non-portable applications.
Bundles
Ceedo
MojoPac
LiberKey
PortableApps.com
U3
WebLaminarTools
WinPenPack
Launchers
Appetizer (Dock application)
ASuite
Launchy
OpenDisc
RocketDock
Development
Scripting languages
Portable Python
Portable NSIS Version
Portable AutoIt
Portable AutoHotkey (zip file)
Portable Perl (Strawberry Perl Portable Version)
Compilers
MinGW
Tiny C Compiler
IDEs
Alice IDE
Portable Eclipse
Portable Code::Blocks (needs MinGW installed, which is portable too)
Portable Dev-C++
Hackety Hack, which is an educational version of Ruby
SharpDevelop Portable
Setup creators
Nullsoft Scriptable Install System Portable (PortableApps.com format)
Visual mapping/productivity tools
XMIND
Graphics
3D modeling and rendering
Anim8or – Free 3D modeling and animating software.
Blender:
BlenderPortable
Blender Pocket
XBlender
Animation
Anim8or
Blender
Pivot Stickfigure Animator
Graphic editors
ArtRage
Artweaver
Dia
EVE
Fotografix
GIMP:
GIMP Portable VS 2008 is the Gimp portable version of Gimp on Windows platforms (Windows XP, Vista, NT Server 2003, NT Server 2008)
Portable Gimp – for Mac OS X
X-Gimp
X-GimpShop
Inkscape:
X-Inkscape
Portable Inkscape – for Mac OS X
IrfanView
Pixia
Tux Paint
Icon editors
@icon sushi
GIMP – Supports reading and writing Windows ICO files.
IcoFX
IrfanView – Supports converting graphic file formats into Windows ICO files.
Viewers
FastStone Image Viewer: supports screen capture, multiple pix into a single PDF
Irfanview
XnView
Documen
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https://en.wikipedia.org/wiki/Yield%20%28engineering%29
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In materials science and engineering, the yield point is the point on a stress-strain curve that indicates the limit of elastic behavior and the beginning of plastic behavior. Below the yield point, a material will deform elastically and will return to its original shape when the applied stress is removed. Once the yield point is passed, some fraction of the deformation will be permanent and non-reversible and is known as plastic deformation.
The yield strength or yield stress is a material property and is the stress corresponding to the yield point at which the material begins to deform plastically. The yield strength is often used to determine the maximum allowable load in a mechanical component, since it represents the upper limit to forces that can be applied without producing permanent deformation. In some materials, such as aluminium, there is a gradual onset of non-linear behavior, and no precise yield point. In such a case, the offset yield point (or proof stress) is taken as the stress at which 0.2% plastic deformation occurs. Yielding is a gradual failure mode which is normally not catastrophic, unlike ultimate failure.
In solid mechanics, the yield point can be specified in terms of the three-dimensional principal stresses () with a yield surface or a yield criterion. A variety of yield criteria have been developed for different materials.
Definition
It is often difficult to precisely define yielding due to the wide variety of stress–strain curves exhibited by real materials. In addition, there are several possible ways to define yielding:
True elastic limit The lowest stress at which dislocations move. This definition is rarely used since dislocations move at very low stresses, and detecting such movement is very difficult.
Proportionality limit Up to this amount of stress, stress is proportional to strain (Hooke's law), so the stress-strain graph is a straight line, and the gradient will be equal to the elastic modulus of the material.
Elastic li
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https://en.wikipedia.org/wiki/Motion%20graphs%20and%20derivatives
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In mechanics, the derivative of the position vs. time graph of an object is equal to the velocity of the object. In the International System of Units, the position of the moving object is measured in meters relative to the origin, while the time is measured in seconds. Placing position on the y-axis and time on the x-axis, the slope of the curve is given by:
Here is the position of the object, and is the time. Therefore, the slope of the curve gives the change in position divided by the change in time, which is the definition of the average velocity for that interval of time on the graph. If this interval is made to be infinitesimally small, such that becomes and becomes , the result is the instantaneous velocity at time , or the derivative of the position with respect to time.
A similar fact also holds true for the velocity vs. time graph. The slope of a velocity vs. time graph is acceleration, this time, placing velocity on the y-axis and time on the x-axis. Again the slope of a line is change in over change in :
where is the velocity, and is the time. This slope therefore defines the average acceleration over the interval, and reducing the interval infinitesimally gives , the instantaneous acceleration at time , or the derivative of the velocity with respect to time (or the second derivative of the position with respect to time). In SI, this slope or derivative is expressed in the units of meters per second per second (, usually termed "meters per second-squared").
Since the velocity of the object is the derivative of the position graph, the area under the line in the velocity vs. time graph is the displacement of the object. (Velocity is on the y-axis and time on the x-axis. Multiplying the velocity by the time, the time cancels out, and only displacement remains.)
The same multiplication rule holds true for acceleration vs. time graphs. When acceleration is multiplied
Variable rates of change
The expressions given above apply only when the rate o
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https://en.wikipedia.org/wiki/MOS%20Technology%20CIA
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The 6526/8520 Complex Interface Adapter (CIA) was an integrated circuit made by MOS Technology. It served as an I/O port controller for the 6502 family of microprocessors, providing for parallel and serial I/O capabilities as well as timers and a Time-of-Day (TOD) clock. The device's most prominent use was in the Commodore 64 and Commodore 128(D), each of which included two CIA chips. The Commodore 1570 and Commodore 1571 floppy disk drives contained one CIA each. Furthermore, the Amiga home computers and the Commodore 1581 floppy disk drive employed a modified variant of the CIA circuit called 8520. 8520 is functionally equivalent to the 6526 except for the simplified TOD circuitry. Predecessor to CIA was PIA.
Parallel I/O
The CIA had two 8-bit bidirectional parallel I/O ports. Each port had a corresponding Data Direction Register, which allowed each data line to be individually set to input or output mode. A read of these ports always returned the status of the individual lines, regardless of the data direction that had been set.
Serial I/O
An internal bidirectional 8-bit shift register enabled the CIA to handle serial I/O. The chip could accept serial input clocked from an external source, and could send serial output clocked with one of the built-in programmable timers. An interrupt was generated whenever an 8-bit serial transfer had completed. It was possible to implement a simple "network" by connecting the shift register and clock outputs of several computers together.
The maximum bitrate is 500 kbit/s for the 2 MHz version.
The CIA incorporates a fix to a bug in the serial-shift register in the earlier 6522 VIA. The CIA was originally intended to allow fast communication with a disk drive, but in the end couldn't be used because of a desire to keep disk drive compatibility with the VIC-20; in practice the firmware of 1541 drive had to be made even slower than its VIC-20 predecessor to workaround a behaviour of the C64's video processor, that, when dra
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https://en.wikipedia.org/wiki/1seg
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is a mobile terrestrial digital audio/video and data broadcasting service in Japan, Argentina, Brazil, Chile, Uruguay, Paraguay, Peru and the Philippines. Service began experimentally during 2005 and commercially on April 1, 2006. It is designed as a component of ISDB-T, the terrestrial digital broadcast system used in those countries, as each channel is divided into 13 segments, with a further segment separating it from the next channel; an HDTV broadcast signal occupies 12 segments, leaving the remaining (13th) segment for mobile receivers, hence the name, "1seg" or "One Seg".
Its use in Brazil was established in late 2007 (starting in just a few cities), with a slight difference from the Japanese counterpart: it is broadcast under a 30 frame/s transmission setting (Japanese broadcasts are under the 15 frame/s transmission setting).
Technical information
The ISDB-T system uses the UHF band at frequencies between 470 and 770 MHz (806 MHz in Brazil), giving a total bandwidth 300 MHz. The bandwidth is divided into fifty name channels 13 through 62. Each channel is 6 MHz wide consisting of a 5.57 MHz wide signalling band and a 430 kHz guard band to limit cross channel interference. Each of these channels is further divided into 13 segments, each with 428 kHz of bandwidth. 1 seg uses a single of these segments to carry the 1seg transport stream.
1seg, like ISDB-T uses QPSK for modulation, with 2/3 forward error correction and 1/4 guard ratio. The total datarate is 416 kbit/s.
The television system uses an H.264/MPEG-4 AVC video stream and an HE-AAC audio stream multiplexed into an MPEG transport stream. The maximum video resolution is 320x240 pixels, with a video bitrate of between 220 and 320 kbit/s. Audio conforms to HE-AAC profile, with a bitrate of 48 to 64 kbit/s. Additional data (EPG, interactive services, etc.) is transmitted using BML and occupies the remaining 10 to 100 kbit/s of bandwidth.
Conditional access and copy control are implemented in 1seg broa
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https://en.wikipedia.org/wiki/Information%20security%20standards
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Information security standards or cyber security standards are techniques generally outlined in published materials that attempt to protect the cyber environment of a user or organization. This environment includes users themselves, networks, devices, all software, processes, information in storage or transit, applications, services, and systems that can be connected directly or indirectly to networks.
The principal objective is to reduce the risks, including preventing or mitigating cyber-attacks. These published materials consist of tools, policies, security concepts, security safeguards, guidelines, risk management approaches, actions, training, best practices, assurance and technologies.
History
Cybersecurity standards have existed over several decades as users and providers have collaborated in many domestic and international forums to effect the necessary capabilities, policies, and practices – generally emerging from work at the Stanford Consortium for Research on Information Security and Policy in the 1990s.
A 2016 US security framework adoption study reported that 70% of the surveyed organizations the NIST Cybersecurity Framework as the most popular best practice for Information Technology (IT) computer security, but many note that it requires significant investment. Cross-border, cyber-exfiltration operations by law enforcement agencies to counter international criminal activities on the dark web raise complex jurisdictional questions that remain, to some extent, unanswered. Tensions between domestic law enforcement efforts to conduct cross-border cyber-exfiltration operations and international jurisdiction are likely to continue to provide improved cybersecurity norms.
International Standards
The subsections below detail international standards related to cybersecurity.
ISO/IEC 27001 and 27002
ISO/IEC 27001, part of the growing ISO/IEC 27000 family of standards, is an information security management system (ISMS) standard, of which the last revis
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https://en.wikipedia.org/wiki/KQCA
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KQCA (channel 58) is a television station licensed to Stockton, California, United States, serving the Sacramento area as a dual affiliate of The CW and MyNetworkTV. It is owned by Hearst Television alongside NBC affiliate KCRA-TV (channel 3). Both stations share studios on Television Circle off D Street in downtown Sacramento, while KQCA's transmitter is located in Walnut Grove, California.
History
The station first signed on the air on April 13, 1986, as KSCH. The first program to air on the station was a "preview" show hosted by Jim Finnerty and Lori Sequest. It was 51 percent owned by Schuyler Communications, Inc., and 49 percent by the SFN Companies. It originally operated as an independent station and aired classic television series from the 1950s, 1960s, and 1970s, as well as some daytime programs that were preempted by KCRA-TV and KXTV (channel 10). The station originally operated from studios located on West Weber Avenue in Stockton. KSCH was also the first station in the Sacramento market to provide stereo sound from its sign-on.
On August 9 of that year, SFN sold the station to Pegasus Broadcasting, which consisted of SFN management and outside investors; channel 58 along with three other television stations and three radio stations sold for $154 million. In 1988, the station moved its studios to a new building located on Gold Canal Drive in Rancho Cordova. In 1990, GE Capital, which had been one of the investors that formed Pegasus, purchased the company outright.
In 1993, GE Capital began shopping KSCH-TV for sale; in one potential proposal, both KSCH and Koplar Communications-owned KRBK (channel 31, now KMAX-TV) would have been sold to one buyer, who would have been able to sell off one of the stations to a noncompetitive entity. In 1994, Sacramento restaurant owner Wing Fat and Barbara Scurfield purchased KSCH-TV from GE Capital for $8 million. The new owners entered into a local marketing agreement with Kelly Broadcasting, then-owner of KCRA. KCRA
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https://en.wikipedia.org/wiki/Hindu%E2%80%93Arabic%20numeral%20system
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The Hindu–Arabic numeral system or Indo-Arabic numeral system (also called the Hindu numeral system or Arabic numeral system) is a positional base ten numeral system for representing integers, which can be extended to include non-integers, i.e the Decimal numeral system, which is the most common system for the symbolic representation of numbers in the world.
It was invented between the 1st and 4th centuries by Indian mathematicians. The system was adopted in Arabic mathematics by the 9th century. It became more widely known through the writings of the Persian mathematician Al-Khwārizmī (On the Calculation with Hindu Numerals, ) and Arab mathematician Al-Kindi (On the Use of the Hindu Numerals, ). The system had spread to medieval Europe by the High Middle Ages.
The system is based upon ten (originally nine) glyphs. The symbols (glyphs) used to represent the system are in principle independent of the system itself. The glyphs in actual use are descended from Brahmi numerals and have split into various typographical variants since the Middle Ages.
These symbol sets can be divided into three main families: Western Arabic numerals used in the Greater Maghreb and in Europe; Eastern Arabic numerals used in the Middle East; and the Indian numerals in various scripts used in the Indian subcontinent.
Origins
The HinduArabic or IndoArabic numerals were invented by mathematicians in India. Persian and Arabic mathematicians called them "Hindu numerals". Later they came to be called "Arabic numerals" in Europe because they were introduced to the West by Arab merchants. According to some sources, this number system may have originated in Chinese Shang numerals (1200 BC), which was also a decimal positional numeral system.
Positional notation
The Hindu–Arabic system is designed for positional notation in a decimal system. In a more developed form, positional notation also uses a decimal marker (at first a mark over the ones digit but now more commonly a decimal point or a d
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https://en.wikipedia.org/wiki/Park%20flyer
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Park flyers are a class of small, primarily electric powered radio-controlled aircraft. The smallest class of park flyers are called micro planes and can be used in an enclosed area such as a gymnasium or a living room, while larger park flyers are used at park flyer sites. Models with low flying speed are more susceptible to wind and turbulence. Park flyers weigh no more than 2 pounds (0.91 kg), allowing park flyers to have a speed limit of less than half of the current wind speed.
Park flyers are a cost-effective and convenient way for beginners to get involved in the hobby of RC flight. Even after serious crash damage, the aircraft's components are still repairable. They may be flown in residential areas because of their modest size and silent operation. Clubs exist to assist newcomers and offer details on suitable takeoff spots.
Types of park flyers
Ready-to-fly (RTF) park flyers require no construction or installation. Users may need to perform basic assembling to fly the aircraft. Almost ready to fly (ARF) park flyers require construction and installation of different parts by the users.
Advanced electronic and material technologies have aided in the development of high-performance, park flyer sized “3D-flyers”, or fully aerobatic aircraft capable of extreme high g maneuvers and nose-up hovering.
A park flyer named the SQUIRT has been entitled as “America's park flyer” due to its high travelling distance of over 26,000 miles (41,842.94 km) within the United States of America and being flown by over 700 different pilots. This was known as the Wings Across America 2008 adventure.
Safety
Certain park flyers (especially small delta-wings) can fly at a dangerous speed, which might cause injuries to passers-by. A standard precaution is keeping an appropriate distance from the public. The Academy of Model Aeronautics recommends a minimum safe distance of at least 50 feet (15.24 m) from any spectators other than the pilot.
See also
RC Aircraft Kit Manufactur
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https://en.wikipedia.org/wiki/Activation
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Activation, in chemistry and biology, is the process whereby something is prepared or excited for a subsequent reaction.
Chemistry
In chemistry, "activation" refers to the reversible transition of a molecule into a nearly identical chemical or physical state, with the defining characteristic being that this resultant state exhibits an increased propensity to undergo a specified chemical reaction. Thus, activation is conceptually the opposite of protection, in which the resulting state exhibits a decreased propensity to undergo a certain reaction.
The energy of activation specifies the amount of free energy the reactants must possess (in addition to their rest energy) in order to initiate their conversion into corresponding products—that is, in order to reach the transition state for the reaction. The energy needed for activation can be quite small, and often it is provided by the natural random thermal fluctuations of the molecules themselves (i.e. without any external sources of energy).
The branch of chemistry that deals with this topic is called chemical kinetics.
Biology
Biochemistry
In biochemistry, activation, specifically called bioactivation, is where enzymes or other biologically active molecules acquire the ability to perform their biological function, such as inactive proenzymes being converted into active enzymes that are able to catalyze their substrates' reactions into products. Bioactivation may also refer to the process where inactive prodrugs are converted into their active metabolites, or the toxication of protoxins into actual toxins.
An enzyme may be reversibly or irreversibly bioactivated. A major mechanism of irreversible bioactivation is where a piece of a protein is cut off by cleavage, producing an enzyme that will then stay active. A major mechanism of reversible bioactivation is substrate presentation where an enzyme translocates near its substrate. Another reversible reaction is where a cofactor binds to an enzyme, which then rem
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https://en.wikipedia.org/wiki/Hotelling%27s%20lemma
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Hotelling's lemma is a result in microeconomics that relates the supply of a good to the maximum profit of the producer. It was first shown by Harold Hotelling, and is widely used in the theory of the firm.
Specifically, it states: The rate of an increase in maximized profits with respect to a price increase is equal to the net supply of the good. In other words, if the firm makes its choices to maximize profits, then the choices can be recovered from the knowledge of the maximum profit function.
Formal Statement
Let denote a variable price, and be a constant cost of each input. Let be a mapping from the price to a set of feasible input choices . Let be the production function, and be the net supply.
The maximum profit can be written by
Then the lemma states that if the profit is differentiable at , the maximizing net supply is given by
Proof for Hotelling's lemma
The lemma is a corollary of the envelope theorem.
Specifically, the maximum profit can be rewritten as where is the maximizing input corresponding to . Due to the optimality, the first order condition gives
By taking the derivative by at ,
where the second equality is due to (). QED
Application of Hotelling's lemma
Consider the following example. Let output have price and inputs and have prices and . Suppose the production function is . The unmaximized profit function is . From this can be derived the profit-maximizing choices of inputs and the maximized profit function, a function just of the input and output prices, which is
Hotelling's Lemma says that from the maximized profit function we can find the profit-maximizing choices of output and input by taking partial derivatives:
Note that Hotelling's lemma gives the net supplies, which are positive for outputs and negative for inputs, since profit rises with output prices and falls with input prices.
Criticisms and empirical evidence
A number of criticisms have been made with regards to the use and application of Hotellin
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https://en.wikipedia.org/wiki/Dioptra
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A dioptra (sometimes also named dioptre or diopter, from ) is a classical astronomical and surveying instrument, dating from the 3rd century BC. The dioptra was a sighting tube or, alternatively, a rod with a sight at both ends, attached to a stand. If fitted with protractors, it could be used to measure angles.
Use
Greek astronomers used the dioptra to measure the positions of stars; both Euclid and Geminus refer to the dioptra in their astronomical works.
It continued in use as an effective surveying tool. Adapted to surveying, the dioptra is similar to the theodolite, or surveyor's transit, which dates to the sixteenth century. It is a more accurate version of the groma.
There is some speculation that it may have been used to build the Eupalinian aqueduct. Called "one of the greatest engineering achievements of ancient times," it is a tunnel 1,036 meters (4,000 ft) long, "excavated through Mount Kastro on the Greek island of Samos, in the 6th century BCE" during the reign of Polycrates. Scholars disagree, however, whether the dioptra was available that early.
An entire book about the construction and surveying usage of the dioptra is credited to Hero of Alexandria (also known as Heron; a brief description of the book is available online; see Lahanas link, below). Hero was "one of history’s most ingenious engineers and applied mathematicians."
The dioptra was used extensively on aqueduct building projects. Screw turns on several different parts of the instrument made it easy to calibrate for very precise measurements
The dioptra was replaced as a surveying instrument by the theodolite.
See also
Alidade
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https://en.wikipedia.org/wiki/Envelope%20theorem
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In mathematics and economics, the envelope theorem is a major result about the differentiability properties of the value function of a parameterized optimization problem. As we change parameters of the objective, the envelope theorem shows that, in a certain sense, changes in the optimizer of the objective do not contribute to the change in the objective function. The envelope theorem is an important tool for comparative statics of optimization models.
The term envelope derives from describing the graph of the value function as the "upper envelope" of the graphs of the parameterized family of functions that are optimized.
Statement
Let and be real-valued continuously differentiable functions on , where are choice variables and are parameters, and consider the problem of choosing , for a given , so as to:
subject to and .
The Lagrangian expression of this problem is given by
where are the Lagrange multipliers. Now let and together be the solution that maximizes the objective function f subject to the constraints (and hence are saddle points of the Lagrangian),
and define the value function
Then we have the following theorem.
Theorem: Assume that and are continuously differentiable. Then
where .
For arbitrary choice sets
Let denote the choice set and let the relevant parameter be . Letting denote the parameterized objective function, the value function and the optimal choice correspondence (set-valued function) are given by:
"Envelope theorems" describe sufficient conditions for the value function to be differentiable in the parameter and describe its derivative as
where denotes the partial derivative of with respect to . Namely, the derivative of the value function with respect to the parameter equals the partial derivative of the objective function with respect to holding the maximizer fixed at its optimal level.
Traditional envelope theorem derivations use the first-order condition for (), which requires that the choice set have t
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https://en.wikipedia.org/wiki/B-Dienst
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The B-Dienst (, observation service), also called xB-Dienst, X-B-Dienst and χB-Dienst, was a Department of the German Naval Intelligence Service (, MND III) of the OKM, that dealt with the interception and recording, decoding and analysis of the enemy, in particular British radio communications before and during World War II. B-Dienst worked on cryptanalysis and deciphering (decrypting) of enemy and neutral states' message traffic and security control of Kriegsmarine key processes and machinery.
"The ultimate goal of all evaluation was recognizing the opponent's goal by pro-active identification of data."
B-Dienst was instrumental in moulding Wehrmacht operations during the Battles of Norway and France in spring 1940, primarily due to the cryptanalysis successes it had achieved against early and less secure British Naval ciphers.
B-Dienst broke British Naval Combined Cypher No. 3 in October 1941, which was used to encrypt all communications between naval personnel, for Allied North Atlantic convoys. This enabled B-Dienst to provide valuable signals intelligence for the German Navy in the Battle of the Atlantic. The intelligence flow largely ended when the Admiralty introduced Naval Cipher No. 5 on 10 June 1943. The new cipher became secure in January 1944 with the introduction of the Stencil Subtractor system which was used to recipher it.
Background
The B-Dienst unit began as the German Radio Monitoring Service, or educational and news analysis service () by the end of World War I, in 1918, as part of the navy of the German Empire.
A counterpart to the B service on the British side was the Y-service or Y Service. The Y was onomatopoeic for the initial syllable of the word wireless, similar to the B initial for the German service.
Little was known outside about the internal organization and workings of the B-Dienst section. After the armistice of Italy (Armistice of Cassibile), officers of the Italian naval communications intelligence (SIM, ) in conversation
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https://en.wikipedia.org/wiki/Disk%20encryption%20theory
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Disk encryption is a special case of data at rest protection when the storage medium is a sector-addressable device (e.g., a hard disk). This article presents cryptographic aspects of the problem. For an overview, see disk encryption. For discussion of different software packages and hardware devices devoted to this problem, see disk encryption software and disk encryption hardware.
Problem definition
Disk encryption methods aim to provide three distinct properties:
The data on the disk should remain confidential.
Data retrieval and storage should both be fast operations, no matter where on the disk the data is stored.
The encryption method should not waste disk space (i.e., the amount of storage used for encrypted data should not be significantly larger than the size of plaintext).
The first property requires defining an adversary from whom the data is being kept confidential. The strongest adversaries studied in the field of disk encryption have these abilities:
they can read the raw contents of the disk at any time;
they can request the disk to encrypt and store arbitrary files of their choosing;
and they can modify unused sectors on the disk and then request their decryption.
A method provides good confidentiality if the only information such an adversary can determine over time is whether the data in a sector has or has not changed since the last time they looked.
The second property requires dividing the disk into several sectors, usually 512 bytes ( bits) long, which are encrypted and decrypted independently of each other. In turn, if the data is to stay confidential, the encryption method must be tweakable; no two sectors should be processed in exactly the same way. Otherwise, the adversary could decrypt any sector of the disk by copying it to an unused sector of the disk and requesting its decryption.
The third property is generally non-controversial. However, it indirectly prohibits the use of stream ciphers, since stream ciphers require, for the
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https://en.wikipedia.org/wiki/Royal%20Belgian%20Entomological%20Society
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The Royal Belgian Entomological Society (; ) is a learned society based in Brussels. It is devoted to entomology, the study of insects. It was founded on 9 April 1855 with Edmond de Sélys Longchamps as its first president.
The society publishes the Bulletin, the Belgian Journal of Entomology and the Mémoires.
External links
Belgian Journal of Entomology Online
Entomological societies
Scientific organisations based in Belgium
Organisations based in Belgium with royal patronage
Organisations based in Brussels
Organizations established in 1855
1855 establishments in Belgium
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https://en.wikipedia.org/wiki/Maggi
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Maggi (, ) is an international brand of seasonings, instant soups, and noodles that originated in Switzerland in the late 19th century. The Maggi company was acquired by Nestlé in 1947.
History
Early history
In 1869, Julius Maggi (1846–1912) took over his father's mill business in Kemptthal, Switzerland. Under his leadership, the business developed into one of the pioneers of industrial food production, with the aim of improving the diet of working-class families through better nutrient supply and faster preparation.
In 1882, at a meeting of the Swiss "Common Good Society" (), the doctor and factory inspector Fridolin Schuler spoke about the miserable nutritional situation of the factory workers: women workers no longer had enough time to cook for their families; cold meals or alcohol often replaced warm meals; meals were served in factory canteens and were cheap but not sufficiently nutritious. The consequences were malnutrition, stomach diseases, and high infant mortality. Schuler advocated for diets based in high-protein, easily digestible pulses/legumes. He demanded that such meals should be offered to the working class in a convenient form for quick preparation and at a cheap price. The Society turned to the Maggi company, among others.
Julius Maggi experimented for two years with different methods of mechanical and chemical processing of legumes and different mixtures. The results were presented to the representatives of the Society on 19 November 1884. They approved the results and signed a contract to exclusively recommend Maggi's legumes for a period of three years. Maggi in turn guaranteed a fixed price and regular product controls for sales in Switzerland. However, the Society was accused of representing the interests of a private company. The Maggi company, on the other hand, had difficulties challenging other suppliers of soup flour on the market, despite support from the Society.
Since 1884, Maggi has been offering flour made from protein-rich
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https://en.wikipedia.org/wiki/Scale%20analysis%20%28mathematics%29
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Scale analysis (or order-of-magnitude analysis) is a powerful tool used in the mathematical sciences for the simplification of equations with many terms. First the approximate magnitude of individual terms in the equations is determined. Then some negligibly small terms may be ignored.
Example: vertical momentum in synoptic-scale meteorology
Consider for example the momentum equation of the Navier–Stokes equations in the vertical coordinate direction of the atmosphere
where R is Earth radius, Ω is frequency of rotation of the Earth, g is gravitational acceleration, φ is latitude, ρ is density of air and ν is kinematic viscosity of air (we can neglect turbulence in free atmosphere).
In synoptic scale we can expect horizontal velocities about U = 101 m.s−1 and vertical about W = 10−2 m.s−1. Horizontal scale is L = 106 m and vertical scale is H = 104 m. Typical time scale is T = L/U = 105 s. Pressure differences in troposphere are ΔP = 104 Pa and density of air ρ = 100 kg⋅m−3. Other physical properties are approximately:
R = 6.378 × 106 m;
Ω = 7.292 × 10−5 rad⋅s−1;
ν = 1.46 × 10−5 m2⋅s−1;
g = 9.81 m⋅s−2.
Estimates of the different terms in equation () can be made using their scales:
Now we can introduce these scales and their values into equation ():
We can see that all terms — except the first and second on the right-hand side — are negligibly small. Thus we can simplify the vertical momentum equation to the hydrostatic equilibrium equation:
Rules of scale analysis
Scale analysis is very useful and widely used tool for solving problems in the area of heat transfer and fluid mechanics, pressure-driven wall jet, separating flows behind backward-facing steps, jet diffusion flames, study of linear and non-linear dynamics. Scale analysis is an effective shortcut for obtaining approximate solutions to equations often too complicated to solve exactly. The object of scale analysis is to use the basic principles of convective heat transfer to produce order-of-mag
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https://en.wikipedia.org/wiki/Material%20properties%20%28thermodynamics%29
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The thermodynamic properties of materials are intensive thermodynamic parameters which are specific to a given material. Each is directly related to a second order differential of a thermodynamic potential. Examples for a simple 1-component system are:
Compressibility (or its inverse, the bulk modulus)
Isothermal compressibility
Adiabatic compressibility
Specific heat (Note - the extensive analog is the heat capacity)
Specific heat at constant pressure
Specific heat at constant volume
Coefficient of thermal expansion
where P is pressure, V is volume, T is temperature, S is entropy, and N is the number of particles.
For a single component system, only three second derivatives are needed in order to derive all others, and so only three material properties are needed to derive all others. For a single component system, the "standard" three parameters are the isothermal compressibility , the specific heat at constant pressure , and the coefficient of thermal expansion .
For example, the following equations are true:
The three "standard" properties are in fact the three possible second derivatives of the Gibbs free energy with respect to temperature and pressure. Moreover, considering derivatives such as and the related Schwartz relations, shows that the properties triplet is not independent. In fact, one property function can be given as an expression of the two others, up to a reference state value.
The second principle of thermodynamics has implications on the sign of some thermodynamic properties such isothermal compressibility.
See also
List of materials properties (thermal properties)
Heat capacity ratio
Statistical mechanics
Thermodynamic equations
Thermodynamic databases for pure substances
Heat transfer coefficient
Latent heat
Specific heat of melting (Enthalpy of fusion)
Specific heat of vaporization (Enthalpy of vaporization)
Thermal mass
External links
The Dortmund Data Bank is a factual data bank for thermodynamic and t
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https://en.wikipedia.org/wiki/Algebraic%20connectivity
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The algebraic connectivity (also known as Fiedler value or Fiedler eigenvalue after Miroslav Fiedler) of a graph G is the second-smallest eigenvalue (counting multiple eigenvalues separately) of the Laplacian matrix of G. This eigenvalue is greater than 0 if and only if G is a connected graph. This is a corollary to the fact that the number of times 0 appears as an eigenvalue in the Laplacian is the number of connected components in the graph. The magnitude of this value reflects how well connected the overall graph is. It has been used in analyzing the robustness and synchronizability of networks.
Properties
The algebraic connectivity of undirected graphs with nonnegative weights, with the inequality being strict if and only if G is connected. However, the algebraic connectivity can be negative for general directed graphs, even if G is a connected graph. Furthermore, the value of the algebraic connectivity is bounded above by the traditional (vertex) connectivity of the graph, . If the number of vertices of an undirected connected graph with nonnegative edge weights is n and the diameter is D, the algebraic connectivity is also known to be bounded below by , and in fact (in a result due to Brendan McKay) by . For the graph with 6 nodes show above (n=6,D=3) these bound means, 4/18 = 0.222 ≤ algebraic connectivity 0.722 ≤ connectivity 1.
Unlike the traditional connectivity, the algebraic connectivity is dependent on the number of vertices, as well as the way in which vertices are connected. In random graphs, the algebraic connectivity decreases with the number of vertices, and increases with the average degree.
The exact definition of the algebraic connectivity depends on the type of Laplacian used. Fan Chung has developed an extensive theory using a rescaled version of the Laplacian, eliminating the dependence on the number of vertices, so that the bounds are somewhat different.
In models of synchronization on networks, such as the Kuramoto model, the Lap
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https://en.wikipedia.org/wiki/Weighted%20random%20early%20detection
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Weighted random early detection (WRED) is a queueing discipline for a network scheduler suited for congestion avoidance. It is an extension to random early detection (RED) where a single queue may have several different sets of queue thresholds. Each threshold set is associated to a particular traffic class.
For example, a queue may have lower thresholds for lower priority packet. A queue buildup will cause the lower priority packets to be dropped, hence protecting the higher priority packets in the same queue. In this way quality of service prioritization is made possible for important packets from a pool of packets using the same buffer.
It is more likely that standard traffic will be dropped instead of higher prioritized traffic.
Restrictions
On Cisco switches WRED is restricted to
TCP/IP traffic. Only this kind of traffic indicates congestion to the sender to enable a reduction of the transmission rate.
Non-IP traffic will be dropped more often than TCP/IP traffic because it is treated with the lowest possible precedence.
Functional Description
WRED proceeds in this order when a packet arrives:
Calculation of the average queue size.
The arriving packet is queued immediately if the average queue size is below the minimum queue threshold.
Depending on the packet drop probability the packet is either dropped or queued if the average queue size is between the minimum and maximum queue threshold.
The packet is automatically dropped if the average queue size is greater than the maximum threshold.
Calculation of average queue size
The average queue size depends on the previous average as well as the current size of the queue. The calculation formula is given below:
where is the user-configurable exponential weight factor, is the old average and is the current queue size. The previous average is more important for high values of . Peaks and lows in queue size are smoothed by a high value. For low values of , the average queue size is close to the curren
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https://en.wikipedia.org/wiki/Secular%20equilibrium
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In nuclear physics, secular equilibrium is a situation in which the quantity of a radioactive isotope remains constant because its production rate (e.g., due to decay of a parent isotope) is equal to its decay rate.
In radioactive decay
Secular equilibrium can occur in a radioactive decay chain only if the half-life of the daughter radionuclide B is much shorter than the half-life of the parent radionuclide A. In such a case, the decay rate of A and hence the production rate of B is approximately constant, because the half-life of A is very long compared to the time scales considered. The quantity of radionuclide B builds up until the number of B atoms decaying per unit time becomes equal to the number being produced per unit time. The quantity of radionuclide B then reaches a constant, equilibrium value. Assuming the initial concentration of radionuclide B is zero, full equilibrium usually takes several half-lives of radionuclide B to establish.
The quantity of radionuclide B when secular equilibrium is reached is determined by the quantity of its parent A and the half-lives of the two radionuclide. That can be seen from the time rate of change of the number of atoms of radionuclide B:
where λA and λB are the decay constants of radionuclide A and B, related to their half-lives t1/2 by , and NA and NB are the number of atoms of A and B at a given time.
Secular equilibrium occurs when , or
Over long enough times, comparable to the half-life of radionuclide A, the secular equilibrium is only approximate; NA decays away according to
and the "equilibrium" quantity of radionuclide B declines in turn. For times short compared to the half-life of A, and the exponential can be approximated as 1.
See also
Bateman equation
Transient equilibrium
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https://en.wikipedia.org/wiki/Arecoline
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Arecoline () is a nicotinic acid-based mild parasympathomimetic stimulant alkaloid found in the areca nut, the fruit of the areca palm (Areca catechu). It is an odourless oily liquid. It can bring a sense of enhanced alertness and energy, euphoria and relaxation. The psychoactive effects are comparable to that of nicotine.
Chemistry
Arecoline is a base, and its conjugate acid has a pKa ~ 6.8.
Arecoline is volatile in steam, miscible with most organic solvents and water, but extractable from water by ether in presence of dissolved salts. Being basic, arecoline forms salts with acids. The salts are crystalline, but usually deliquescent: the hydrochloride, arecoline•HCl, forms needles, m.p. 158 °C; the hydrobromide, arecoline•HBr, forms slender prisms, mp. 177–179 °C from hot methanol; the aurichloride, arecoline•HAuCl4, is an oil, but the platinichloride, arecoline2•H2PtCl6, mp. 176 °C, crystallizes from water in orange-red rhombohedrons. The methiodide forms glancing prisms, mp. 173-174 °C.
Pharmacology
Arecoline is the primary active ingredient responsible for the central nervous system effects of the areca nut. Arecoline has been compared to nicotine; however, nicotine agonizes nicotinic acetylcholine receptors, whereas arecoline is primarily a partial agonist of muscarinic acetylcholine receptors, leading to its parasympathetic effects. In frogs, arecoline also acts as an antagonist (or very weak partial agonist) at α4 and α6-containing nicotinic acetylcholine receptors and as a silent antagonist at α7 nicotinic receptors, which may account for its anti-inflammatory activity. Arecoline also inhibits AMPK through generation of ROS in several types of cells.
Nervous system
Arecoline promotes excitation and decreases sleeping time. It also enhances learning and memory. Intraperitoneal administration of arecoline decreases locomotor activity dose-dependently. Arecoline reversed scopolamine induced memory loss. It could also decrease symptoms of depression and
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https://en.wikipedia.org/wiki/Pooper-scooper
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A pooper-scooper, or poop scoop, is a device used to pick up animal feces from public places and yards, particularly those of dogs. Pooper-scooper devices often have a bag or bag attachment. 'Poop bags' are alternatives to pooper scoopers, and are simply a bag, usually turned inside out, to carry the feces to a proper disposal area. Sometimes, the person performing the cleanup is also known as the pooper-scooper.
History
The invention is credited to Brooke Miller, of Anaheim, California. The design she patented is a metal bin with a rake-like edge attached to a wooden stick. It also includes a rake-like device to scoop the poop into the scooper and a hatch that can be attached to a garbage bag that fits onto the base. The generic term pooper-scooper has been included in dictionaries since the early 1970s.
Legislation
Around 1935, "Curb Your Dog" signs started appearing in NYC, initiating discussions and correspondence with the Department of Sanitation.
The Village of Great Neck Estates was one of the earliest communities to enact a local ordinance, in 1975, requiring residents to remove pollution on private and public property caused by dogs. Murray Seeman, Jay S. Goodman and Howard Zelikow, advocated in the face of heated opposition.
In 1978, New York State passed the Pooper-Scooper Law. It was so controversial that Mayor Koch needed the New York State Legislature to pass it, after being unable to convince the New York City Council. The New York Times called actress and consumer advocate Fran Lee "New York's foremost fighter against dog dirt".
October 20, 1978, KQED San Francisco news footage featured scenes from a Harvey Milk press conference in Duboce Park in which he discussed the city's new "pooper scooper law" with a how-to demonstration.
Marking the 25th anniversary of the Pooper-scooper law, NYC Mayor Ed Koch was quoted saying, "If you’ve ever stepped in dog doo, you know how important it is to enforce the canine waste law. New Yorkers overwhelmingly
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https://en.wikipedia.org/wiki/Fond
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In the culinary arts, fond is a contraction of fonds de cuisine which is loosely described as "the foundation and working capital of the kitchen". It refers to a flavorful liquid that is used as foundation (fondation in French, hence the abbreviation fond) for other preparations, such as stocks, broths, gravies and sauces.
In popular usage, the word fond is often conveniently used to refer to the stock made from a fond. It is also sometime used colloquially to refer to the solid bits of food found stuck to a pan after something was cooked; more technically, these bits are deglazed with a liquid in order to produce a fond.
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https://en.wikipedia.org/wiki/Thomae%27s%20function
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Thomae's function is a real-valued function of a real variable that can be defined as:
It is named after Carl Johannes Thomae, but has many other names: the popcorn function, the raindrop function, the countable cloud function, the modified Dirichlet function, the ruler function, the Riemann function, or the Stars over Babylon (John Horton Conway's name). Thomae mentioned it as an example for an integrable function with infinitely many discontinuities in an early textbook on Riemann's notion of integration.
Since every rational number has a unique representation with coprime (also termed relatively prime) and , the function is well-defined. Note that is the only number in that is coprime to
It is a modification of the Dirichlet function, which is 1 at rational numbers and 0 elsewhere.
Properties
Related probability distributions
Empirical probability distributions related to Thomae's function appear in DNA sequencing. The human genome is diploid, having two strands per chromosome. When sequenced, small pieces ("reads") are generated: for each spot on the genome, an integer number of reads overlap with it. Their ratio is a rational number, and typically distributed similarly to Thomae's function.
If pairs of positive integers are sampled from a distribution and used to generate ratios , this gives rise to a distribution on the rational numbers. If the integers are independent the distribution can be viewed as a convolution over the rational numbers, . Closed form solutions exist for power-law distributions with a cut-off. If (where is the polylogarithm function) then . In the case of uniform distributions on the set , which is very similar to Thomae's function.
The ruler function
For integers, the exponent of the highest power of 2 dividing gives 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, ... . If 1 is added, or if the 0s are removed, 1, 2, 1, 3, 1, 2, 1, 4, 1, 2, 1, 3, 1, 2, 1, ... . The values resemble tick-marks on a 1/16th graduated ruler, he
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https://en.wikipedia.org/wiki/Telecentric%20lens
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A telecentric lens is a special optical lens (often an objective lens or a camera lens) that has its entrance or exit pupil, or both, at infinity. The size of images produced by a telecentric lens is insensitive to either the distance between an object being imaged and the lens, or the distance between the image plane and the lens, or both, and such an optical property is called telecentricity. Telecentric lenses are used for precision optical two-dimensional measurements, reproduction (e.g., photolithography), and other applications that are sensitive to the image magnification or the angle of incidence of light.
The simplest way to make a lens telecentric is to put the aperture stop at one of the lens's focal points. This makes the chief rays (light rays that pass through the center of the aperture stop) on the other side of the lens parallel to the optical axis for any point in the field of view. Commercially available telecentric lenses are often compound lenses that include multiple lens elements, for improved optical performance. Telecentricity is not a property of the lenses inside the compound lens but is established by the location of the aperture stop in the lens. The aperture stop selects the rays that are passed through the lens and this specific selection is what makes a lens telecentric.
If a lens is not telecentric, it is either entocentric or hypercentric. Common lenses are usually entocentric. In particular, a single lens without a separate aperture stop is entocentric. For such a lens the chief ray originating at any point off of the optical axis is never parallel to the optical axis, neither in front of nor behind the lens. A non-telecentric lens exhibits varying magnification for objects at different distances from the lens. An entocentric lens has a smaller magnification for objects farther away; objects of the same size appear smaller the farther they are away. A hypercentric lens produces larger images the farther the object is away.
A tele
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https://en.wikipedia.org/wiki/Neuroacanthocytosis
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Neuroacanthocytosis is a label applied to several genetic neurological conditions in which the blood contains misshapen, spiculated red blood cells called acanthocytes.
The 'core' neuroacanthocytosis syndromes, in which acanthocytes are a typical feature, are chorea acanthocytosis and McLeod syndrome. Acanthocytes are seen less frequently in other conditions including Huntington's disease-like syndrome 2 (HDL2) and pantothenate kinase-associated neurodegeneration (PKAN).
The neuroacanthocytosis syndromes are caused by a range of genetic mutations and produce a variety of clinical features but primarily produce neurodegeneration of the brain, specifically the basal ganglia.
The diseases are hereditary but rare.
Acanthocytes
The hallmark of the neuroacanthocytosis syndromes is the presence of acanthocytes in peripheral blood. Acanthocytosis originated from the Greek word acantha, meaning thorn. Acanthocytes are spiculated red blood cells and can be caused by altered distribution of membrane lipids or membrane protein/skeleton abnormalities. In neuroacanthocytosis, acanthocytes are caused by protein but not lipid membrane abnormalities
Signs and symptoms
The 'core' neuroacanthocytosis syndromes are chorea acanthocytosis and McLeod syndrome. Acanthocytes are nearly always present in these conditions and they share common clinical features. Some of these features are also seen in the other neurological syndromes associated with neuroacanthocytosis.
A common feature of the core syndromes is chorea: involuntary dance-like movements. In neuroacanthocytosis, this is particularly prominent in the face and mouth which can cause difficulties with speech and eating. These movements are usually abrupt and irregular and present during both rest and sleep.
Individuals with neuroacanthocytosis also often have parkinsonism, the uncontrolled slowness of movements, and dystonia, abnormal body postures. Many affected individuals also have cognitive (intellectual) impairment
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https://en.wikipedia.org/wiki/Chondroblast
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Chondroblasts, or perichondrial cells, is the name given to mesenchymal progenitor cells in situ which, from endochondral ossification, will form chondrocytes in the growing cartilage matrix. Another name for them is subchondral cortico-spongious progenitors. They have euchromatic nuclei and stain by basic dyes.
These cells are extremely important in chondrogenesis due to their role in forming both the chondrocytes and cartilage matrix which will eventually form cartilage. Use of the term is technically inaccurate since mesenchymal progenitors can also technically differentiate into osteoblasts or fat. Chondroblasts are called chondrocytes when they embed themselves in the cartilage matrix, consisting of proteoglycan and collagen fibers, until they lie in the matrix lacunae. Once they embed themselves into the cartilage matrix, they grow the cartilage matrix by growing more cartilage extracellular matrix rather than by dividing further.
Structure
Within adults and developing adults, most chondroblasts are located in the perichondrium. This is a thin layer of connective tissue which protects cartilage and is where chondroblasts help to expand cartilage size whenever prompted to by hormones such as GH, TH, and glycosaminoglycans. They are located on the perichondrium because the perichondrium, located on the outside of developing bone, is not as heavily ensheathed in cartilage extracellular matrix as the interior and because here where capillaries are located. The type of growth maintained by chondroblasts is called appositional bone growth and increases the birth of the affected tissue. It is important to note that perichondrium, and thus chondroblasts, are not found on the articular cartilage surfaces of joints.
Matrix formation and composition
The extracellular matrix secreted by chondroblasts is composed of fibers, collagen, hyaluronic acid, proteoglycans, glycoproteins, water, and a host of macromolecules. Within finished cartilage, collagen fibers compose 10
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https://en.wikipedia.org/wiki/Z-value%20%28temperature%29
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"F0" is defined as the number of equivalent minutes of steam sterilization at temperature 121.1 °C (250 °F) delivered to a container or unit of product calculated using a z-value of 10 °C. The term F-value or "FTref/z" is defined as the equivalent number of minutes to a certain reference temperature (Tref) for a certain control microorganism with an established Z-value.
Z-value is a term used in microbial thermal death time calculations. It is the number of degrees the temperature has to be increased to achieve a tenfold (i.e. 1 log10) reduction in the D-value. The D-value of an organism is the time required in a given medium, at a given temperature, for a ten-fold reduction in the number of organisms. It is useful when examining the effectiveness of thermal inactivations under different conditions, for example in food cooking and preservation. The z-value is a measure of the change of the D-value with varying temperature, and is a simplified version of an Arrhenius equation and it is equivalent to z=2.303 RT Tref/E.
The z-value of an organism in a particular medium is the temperature change required for the D-value to change by a factor of ten, or put another way, the temperature required for the thermal destruction curve to move one log cycle. It is the reciprocal of the slope resulting from the plot of the logarithm of the D-value versus the temperature at which the D-value was obtained. While the D-value gives the time needed at a certain temperature to kill 90% of the organisms, the z-value relates the resistance of an organism to differing temperatures. The z-value allows calculation of the equivalency of two thermal processes, if the D-value and the z-value are known.
Example: if it takes an increase of 10 °C (18 °F) to move the curve one log, then our z-value is 10. Given a D-value of 4.5 minutes at 150 °C, the D-value can be calculated for 160 °C by reducing the time by 1 log. The new D-value for 160 °C given the z-value is 0.45 minutes. This means
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https://en.wikipedia.org/wiki/Tympanic%20duct
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The tympanic duct or scala tympani is one of the perilymph-filled cavities in the inner ear of humans. It is separated from the cochlear duct by the basilar membrane, and it extends from the round window to the helicotrema, where it continues as vestibular duct.
The purpose of the perilymph-filled tympanic duct and vestibular duct is to transduce the movement of air that causes the tympanic membrane and the ossicles to vibrate, to movement of liquid and the basilar membrane. This movement is conveyed to the organ of Corti inside the cochlear duct, composed of hair cells attached to the basilar membrane and their stereocilia embedded in the tectorial membrane. The movement of the basilar membrane compared to the tectorial membrane causes the stereocilia to bend. They then depolarise and send impulses to the brain via the cochlear nerve. This produces the sensation of sound.
Additional images
See also
Scala vestibuli
Hearing
External links
Slide from University of Kansas
Diagram at IUPUI
Image at University of New England, Maine
Auditory system
Ear
Otology
Audiology
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https://en.wikipedia.org/wiki/Zingerone
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Zingerone, also called vanillylacetone, is a major flavor component of ginger, providing the sweet flavor of cooked ginger. Zingerone is a crystalline solid that is sparingly soluble in water and soluble in ether.
Zingerone is similar in chemical structure to other flavor chemicals such as vanillin and eugenol. It is used as a flavor additive in spice oils and in perfumery to introduce spicy aromas.
Fresh ginger does not contain zingerone, but it is produced by cooking or drying of the ginger root, which causes a reverse aldol reaction on gingerol.
Production
History
Zingerone was first isolated from the ginger root in 1917 by Hiroshi Nomura, a chemistry professor at Tokyo Imperial University. Nomura named the compound and identified the empirical formula of zingerone in his studies at the laboratory of the Agricultural College. He initially identified it as the chemical component contributing pungency to ginger, something further work has disproven.
Current methods
Nomura identified and later patented a method for the synthesis of zingerone, in which vanillin and acetone are reacted under basic conditions to form dehydrozingerone. This compound is obtained in about 95% quantity. This reaction is followed by catalytic hydrogenation of the intermediate compound in order to form zingerone, obtained in approximately 100% quantity.
Biological effects
Ginger compounds have been shown to be active against enterotoxigenic Escherichia coli heat-labile enterotoxin-induced diarrhea. This type of diarrhea is the leading cause of infant death in developing countries. Zingerone is likely the active constituent responsible for the antidiarrheal efficacy of ginger.
Zingerone is recognized as being a particularly efficient free radical scavenger. It is able to scavenge and degrade free radicals and reactive oxygen species in the body, and inhibits enzymes involved in the generation of these reactive oxygen species.
It is used by some flowers to attract pollinating fruit
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https://en.wikipedia.org/wiki/Parametric%20surface
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A parametric surface is a surface in the Euclidean space which is defined by a parametric equation with two parameters Parametric representation is a very general way to specify a surface, as well as implicit representation. Surfaces that occur in two of the main theorems of vector calculus, Stokes' theorem and the divergence theorem, are frequently given in a parametric form. The curvature and arc length of curves on the surface, surface area, differential geometric invariants such as the first and second fundamental forms, Gaussian, mean, and principal curvatures can all be computed from a given parametrization.
Examples
The simplest type of parametric surfaces is given by the graphs of functions of two variables:
A rational surface is a surface that admits parameterizations by a rational function. A rational surface is an algebraic surface. Given an algebraic surface, it is commonly easier to decide if it is rational than to compute its rational parameterization, if it exists.
Surfaces of revolution give another important class of surfaces that can be easily parametrized. If the graph , is rotated about the z-axis then the resulting surface has a parametrization It may also be parameterized showing that, if the function is rational, then the surface is rational.
The straight circular cylinder of radius R about x-axis has the following parametric representation:
Using the spherical coordinates, the unit sphere can be parameterized by This parametrization breaks down at the north and south poles where the azimuth angle θ is not determined uniquely. The sphere is a rational surface.
The same surface admits many different parametrizations. For example, the coordinate z-plane can be parametrized as
for any constants a, b, c, d such that , i.e. the matrix is invertible.
Local differential geometry
The local shape of a parametric surface can be analyzed by considering the Taylor expansion of the function that parametrizes it. The arc length of a cu
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https://en.wikipedia.org/wiki/Radware
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Radware Inc. is an American provider of cybersecurity and application delivery products for physical, cloud and software-defined data centers. Radware's corporate headquarters are located in Mahwah, New Jersey. The company also has offices in Europe, Africa and Asia Pacific regions. The company's global headquarters is in Israel. Radware is a member of the Rad Group of companies and its shares are traded on NASDAQ.
History
Radware co-founder Roy Zisapel has served as President, Chief Executive Officer and Director since the company's inception in April 1997. In 1999, the company had an initial public offering and was listed on the NASDAQ stock exchange. Zisapel holds a 3.4 percent stake in the company. His father, Yehuda Zisapel, is the largest shareholder, with a 15 percent stake.
Acquisitions
In January 2019, Radware expanded its cloud security portfolio with the acquisition of ShieldSquare, a market-leading bot management solutions provider. In January 2017, Radware acquired Seculert, a SaaS cloud-based provider of protection against enterprise network breach and data exfiltration. In February 2013, Radware acquired Strangeloop Networks, a leader in web performance optimization (WPO) solutions for e-commerce and enterprise applications. In April 2007, Radware acquired Covelight Systems, a provider of web application auditing and monitoring tools. In February 2009, Radware acquired Nortel's application delivery business. In November 2005, Radware acquired V-Secure Technologies, a leading provider of behavioral-based network intrusion prevention products.
Products
Radware's products and services include cloud services (Cloud WAF, Cloud DDoS Protection, Cloud Workload Protection, Cloud Web Acceleration, Cloud Malware Protection, and Bot Manager), application and network security (DefensePro, AppWall, DefenseFlow), application delivery and load balancing (Alteon, AppWall, FastView, AppXML, LinkProof NG), and management and monitoring (APSolute Vision, MSSP
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https://en.wikipedia.org/wiki/Heptad%20repeat
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The heptad repeat is an example of a structural motif that consists of a repeating pattern of seven amino acids:
a b c d e f g
H P P H C P C
where H represents hydrophobic residues, C represents, typically, charged residues, and P represents polar (and, therefore, hydrophilic) residues. The positions of the heptad repeat are commonly denoted by the lowercase letters a through g.
These motifs are the basis for most coiled coils and, in particular, leucine zippers, which have predominantly leucine in the d position of the heptad repeat.
A conformational change in a heptad repeat in the SARS-CoV-2 spike protein facilitates entry of the virus into the host cell membrane.
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https://en.wikipedia.org/wiki/MOS%20Technology%20SPI
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The 6529 Single Port Interface (SPI aka PIO) was an integrated circuit made by MOS Technology. It served as an I/O controller for the 6502 family of microprocessors, providing a single 8-bit digital bidirectional parallel I/O port. Unlike the more sophisticated 6522 VIA and 6526 CIA, it did not allow the data direction for each I/O line to be separately specified, nor did it support serial I/O or contain any timer capabilities. Because of this, it did not achieve widespread use.
6529 ICs were available in 1 MHz, 2 MHz, and 3 MHz versions. The form factor was a JEDEC-standard 20-pin ceramic or plastic DIP.
The 6529 differs from a 74(LS)639 bidirectional three-state/open-Collector-busdriver in that the 6529 has passive output pullups and power-on reset circuitry.
External links
MOS 6529 datasheet
MOS 6529 datasheet (GIF format, zipped)
MOS Technology integrated circuits
Input/output integrated circuits
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https://en.wikipedia.org/wiki/Superprism
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A superprism is a photonic crystal in which an entering beam of light will lead to an extremely large angular dispersion. The ability of the photonic crystal to send optical beams with different wavelengths to considerably different angles in space in superprisms has been used to demonstrate wavelength demultiplexing in these structures. The first superprism also modified group velocity rather than phase velocity in order to achieve the "superprism phenomena". This effect was interpreted as anisotropic dispersion in contrast to an isotropic dispersion. Furthermore, the two beams of light appear to show negative bending within the crystal.
See also
Mirror Pack
Superlens
Prism (optics)
Metamaterial
Perfect mirror
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https://en.wikipedia.org/wiki/Biomedical%20scientist
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A biomedical scientist is a scientist trained in biology, particularly in the context of medical laboratory sciences or laboratory medicine. These scientists work to gain knowledge on the main principles of how the human body works and to find new ways to cure or treat disease by developing advanced diagnostic tools or new therapeutic strategies. The research of biomedical scientists is referred to as biomedical research.
Description
The specific activities of the biomedical scientist can differ in various parts of the world and vary with the level of education. Generally speaking, biomedical scientists conduct research in a laboratory setting, using living organisms as models to conduct experiments. These can include cultured human or animal cells grown outside of the whole organism, small animals such as flies, worms, fish, mice, and rats, or, rarely, larger animals and primates. Biomedical scientists may also work directly with human tissue specimens to perform experiments as well as participate in clinical research.
Biomedical scientists employ a variety of techniques in order to carry out laboratory experiments. These include:
Molecular and biochemical techniques
Electrophoresis and blotting
Immunostaining
Chromatography
Mass spectrometry
PCR and sequencing
Microarrays
Imaging technologies
Light, fluorescence, and electron microscopy
MRI
PET
X-ray
Genetic engineering/modification
Transfection
Viral transduction
Transgenic model organisms
Electrophysiology techniques
Patch clamp
EEG, EKG, ERG
In silico techniques
Bioinformatics
Computational biology
Level of education
Biomedical scientists typically obtain a bachelor of science degree, and usually take postgraduate studies leading to a diploma, master or doctorate. This degree is necessary for faculty positions at academic institutions, as well as senior scientist positions at most companies. Some biomedical scientists also possess a medical degree (MD, DO, PharmD, Doctor of Medical Laboratory Sciences[MLSD]
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https://en.wikipedia.org/wiki/H%C3%BCckel%20method
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The Hückel method or Hückel molecular orbital theory, proposed by Erich Hückel in 1930, is a simple method for calculating molecular orbitals as linear combinations of atomic orbitals. The theory predicts the molecular orbitals for π-electrons in π-delocalized molecules, such as ethylene, benzene, butadiene, and pyridine. It provides the theoretical basis for Hückel's rule that cyclic, planar molecules or ions with π-electrons are aromatic. It was later extended to conjugated molecules such as pyridine, pyrrole and furan that contain atoms other than carbon and hydrogen (heteroatoms). A more dramatic extension of the method to include σ-electrons, known as the extended Hückel method (EHM), was developed by Roald Hoffmann. The extended Hückel method gives some degree of quantitative accuracy for organic molecules in general (not just planar systems) and was used to provide computational justification for the Woodward–Hoffmann rules. To distinguish the original approach from Hoffmann's extension, the Hückel method is also known as the simple Hückel method (SHM).
Although undeniably a cornerstone of organic chemistry, Hückel's concepts were undeservedly unrecognized for two decades. Pauling and Wheland characterized his approach as "cumbersome" at the time, and their competing resonance theory was relatively easier to understand for chemists without fundamental physics background, even if they couldn't grasp the concept of quantum superposition and confused it with tautomerism. His lack of communication skills contributed: when Robert Robinson sent him a friendly request, he responded arrogantly that he is not interested in organic chemistry.
In spite of its simplicity, the Hückel method in its original form makes qualitatively accurate and chemically useful predictions for many common molecules and is therefore a powerful and widely taught educational tool. It is described in many introductory quantum chemistry and physical organic chemistry textbooks, and organi
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https://en.wikipedia.org/wiki/Software%20appliance
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A software appliance is a software application combined with just enough operating system (JeOS) to run optimally on industry-standard hardware (typically a server) or in a virtual machine. It is a software distribution or firmware that implements a computer appliance.
Virtual appliances are a subset of software appliances. The main distinction is the packaging format and the specificity of the target platform. A virtual appliance is a virtual machine image designed to run on a specific virtualization platform, while a software appliance is often packaged in more generally applicable image format (e.g., Live CD) that supports installations to physical machines and multiple types of virtual machines.
Installing a software appliance to a virtual machine and packaging that into an image, creates a virtual appliance.
Benefits
Software appliances have several benefits over traditional software applications that are installed on top of an operating system:
Simplified deployment: A software appliance encapsulates an application's dependencies in a pre-integrated, self-contained unit. This can dramatically simplify software deployment by freeing users from having to worry about resolving potentially complex OS compatibility issues, library dependencies or undesirable interactions with other applications. This is known as a "toaster."
Improved isolation: software appliances are typically used to run applications in isolation from one another. If the security of an appliance is compromised, or if the appliance crashes, other isolated appliances will not be affected.
Improved performance: A software appliance does not embed any unused operating system services, applications or any form of bloatware hence it does not have to share the hardware resources (CPU, memory, storage space, ...) usually consumed by these on a generic OS setup. This naturally leads to faster boot time and application execution speed. In the case where multiple software applianc
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https://en.wikipedia.org/wiki/MOS%20Technology%20TED
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The 7360/8360 TExt Display (TED) was an integrated circuit made by MOS Technology, Inc. It was a video chip that also contained sound generation hardware, DRAM refresh circuitry, interval timers, and keyboard input handling. It was designed for the Commodore Plus/4 and 16. Packaging consisted of a JEDEC-standard 48-pin DIP.
The only difference between models 7360 and 8360 is the manufacturing technology used; model 8360 is more common.
Video capabilities
The video capabilities provided by the TED were largely a subset of those in the VIC-II. The TED supported five video modes:
Text mode of 40 × 25 characters with 8 × 8 pixels
Multicolor text (4 × 8 pixels per character, double pixel width in the x-direction)
Extended background color mode (8 × 8 pixels per character)
Multicolor Graphics 160 × 200 pixels
Hi-Res Graphics 320 × 200 pixels
of the long visible part of the scan lines is filled with pixels
These modes were largely unchanged from the corresponding VIC-II modes aside from different register and memory mappings (see the article on the VIC-II for information on graphics modes). However, the TED lacked the sprite capabilities of the VIC-II, and so game animation had to be done exclusively with custom character sets like on the VIC-20. This restricted the graphics of C16/Plus 4 games versus the C64. On the VIC-II, sprites used of the die area pushing the transistor count over that of the CPU. In contrast, the TED caches the color attributes on-chip, increasing the SRAM from and does away with the external color RAM.
The TED did include two features that the VIC-II lacked: luminance control and blinking text.
It generated 16 base colors by variations of Pb and Pr chroma signals (with 8 possible steps, ranging from 0, +-0.3826834, +-0.7071068 to +-1.0). Fifteen of these 16 colors (black being the exception) could be assigned one of 8 Y luma values (0.125, 0.25, 0.375, 0.5, 0.625, 0.75, 0.875, 1.0), thus making the TED capable of displaying a far
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https://en.wikipedia.org/wiki/Phenol%20extraction
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Phenol extraction is a laboratory technique that purifies nucleic acid samples using a phenol solution. Phenol is common reagent in extraction because its properties allow for effective nucleic acid extraction, particularly as it strongly denatures proteins, it is a nucleic acid preservative, and it is immiscible in water.
It may also refer to the process of extracting and isolating phenols from raw materials such as coal tar. These purified phenols are used in many industrial and medical compounds and are used as precursors in some synthesis reactions.
Phenol extraction of nucleic acids
Phenol extraction is a widely used technique for purifying nucleic acid samples from cell lysates. To obtain nucleic acids, the cell must be lysed, and the nucleic acids separated from other cell components.
Phenol is a polar substance with a higher density than water (1.07 g/cm3 compared to water's 1.00 g/cm3). When suspended in a water-phenol solution, denatured proteins and unwanted cell components dissolve in the phenol, while polar nucleic acids dissolve in the water phase. The solution may then be centrifuged to separate the phenol and water into distinct organic and aqueous phases. Purified nucleic acids can be precipitated from the aqueous phase of the solution.
Phenol is often used in combination with chloroform. Adding an equal volume of chloroform and phenol ensures a distinct separation between the aqueous and organic phases. Chloroform and phenol are miscible and create a denser solution than phenol alone, aiding the separation of the organic and aqueous layers. This addition of chloroform is useful when removing the aqueous phase to obtain a purified nucleic acid sample.
The pH of the solution must be adjusted specifically for each type of extraction. For DNA extraction, the pH is adjusted to 7.0–8.0. For RNA-specific extraction, the pH is adjusted to 4.5. At pH 4.5, hydrogen ions neutralize the negative charges on the phosphate groups, causing DNA to dissolve
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https://en.wikipedia.org/wiki/Pitch%20shifting
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Pitch shifting is a sound recording technique in which the original pitch of a sound is raised or lowered. Effects units that raise or lower pitch by a pre-designated musical interval (transposition) are called pitch shifters.
Pitch and time shifting
The simplest methods are used to increase pitch and reduce durations or, conversely, reduce pitch and increase duration. This can be done by replaying a sound waveform at a different speed than it was recorded. It could be accomplished on an early reel-to-reel tape recorder by changing the diameter of the capstan or using a different motor. As for vinyl records, placing a finger on the turntable to give friction will retard it, while giving it a "spin" can advance it. As technologies improved, motor speed and pitch control could be achieved electronically by servo drive system circuits.
Pitch shifter and harmonizer
A pitch shifter is a sound effects unit that raises or lowers the pitch of an audio signal by a preset interval. For example, a pitch shifter set to increase the pitch by a fourth will raise each note three diatonic intervals above the notes actually played. Simple pitch shifters raise or lower the pitch by one or two octaves, while more sophisticated devices offer a range of interval alterations. Pitch shifters are included in most audio processors today.
A harmonizer is a type of pitch shifter that combines the pitch-shifted signal with the original to create a two or more note harmony. The Eventide H910 Harmonizer, released in 1975, was one of the first commercially available pitch-shifters and digital multi-effects units. On November 10, 1976, Eventide filed a trademark registration for "Harmonizer" and continues to maintain its rights to the Harmonizer trademark today.
In digital recording, pitch shifting is accomplished through digital signal processing. Older digital processors could often shift pitch only in post-production, whereas many modern devices using computer processing technology can cha
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https://en.wikipedia.org/wiki/Gravitational%20interaction%20of%20antimatter
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The gravitational interaction of antimatter with matter or antimatter has been observed by physicists. As was the consensus among physicists previously, it was experimentally confirmed that gravity attracts both matter and antimatter at the same rate within experimental error.
Antimatter's rarity and tendency to annihilate when brought into contact with matter makes its study a technically demanding task. Furthermore, gravity is much weaker than the other fundamental forces, for reasons still of interest to physicists, complicating efforts to study gravity in systems small enough to be feasibly created in lab, including antimatter systems. Most methods for the creation of antimatter (specifically antihydrogen) result in particles and atoms of high kinetic energy, which are unsuitable for gravity-related study.
Antimatter is gravitationally attracted to matter. The magnitude of the gravitational force is also the same. This is predicted by theoretical arguments like the gravitational equivalence of energy and matter, and has been experimentally verified for antihydrogen. However the equivalence of the gravitational acceleration of matter to matter vs antimatter to matter has an error margin of about 20% ( table 3). Difficulties in creating quantum gravity models have led to the idea that antimatter may react with a slightly different magnitude.
Theories of gravitational attraction
When antimatter was first discovered in 1932, physicists wondered how it would react to gravity. Initial analysis focused on whether antimatter should react the same as matter or react oppositely. Several theoretical arguments arose which convinced physicists that antimatter would react the same as normal matter. They inferred that gravitational repulsion between matter and antimatter was implausible as it would violate CPT invariance, conservation of energy, result in vacuum instability, and result in CP violation. It was also theorized that it would be inconsistent with the results o
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https://en.wikipedia.org/wiki/NYSERNet
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NYSERNet (New York State Education and Research Network) is a non-profit Internet Service Provider in New York State. It mainly provides Internet access to universities, colleges, museums, health care facilities, primary and secondary schools, and research institutions.
History
NYSERNet was founded in 1986 in Troy, New York. Its founders compared NYSERNet's network with the Erie Canal and considered it the next step in two centuries to draw the country together. NYSERNet's network reaches from Buffalo to New York City. Completed in 1987, it was the first statewide regional IP network in the United States. Initial speed of 56 kbps was upgraded to T1 in 1989 and T3 in 1994.
It was the original assignee of AS174 according to RFC1117. This ASN is used today by Cogent Communications for their global network.
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https://en.wikipedia.org/wiki/Difference%20in%20differences
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Difference in differences (DID or DD) is a statistical technique used in econometrics and quantitative research in the social sciences that attempts to mimic an experimental research design using observational study data, by studying the differential effect of a treatment on a 'treatment group' versus a 'control group' in a natural experiment. It calculates the effect of a treatment (i.e., an explanatory variable or an independent variable) on an outcome (i.e., a response variable or dependent variable) by comparing the average change over time in the outcome variable for the treatment group to the average change over time for the control group. Although it is intended to mitigate the effects of extraneous factors and selection bias, depending on how the treatment group is chosen, this method may still be subject to certain biases (e.g., mean regression, reverse causality and omitted variable bias).
In contrast to a time-series estimate of the treatment effect on subjects (which analyzes differences over time) or a cross-section estimate of the treatment effect (which measures the difference between treatment and control groups), difference in differences uses panel data to measure the differences, between the treatment and control group, of the changes in the outcome variable that occur over time.
General definition
Difference in differences requires data measured from a treatment group and a control group at two or more different time periods, specifically at least one time period before "treatment" and at least one time period after "treatment." In the example pictured, the outcome in the treatment group is represented by the line P and the outcome in the control group is represented by the line S. The outcome (dependent) variable in both groups is measured at time 1, before either group has received the treatment (i.e., the independent or explanatory variable), represented by the points P1 and S1. The treatment group then receives or experiences the treatmen
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https://en.wikipedia.org/wiki/Rng%20%28algebra%29
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In mathematics, and more specifically in abstract algebra, a rng (or non-unital ring or pseudo-ring) is an algebraic structure satisfying the same properties as a ring, but without assuming the existence of a multiplicative identity. The term rng (IPA: ) is meant to suggest that it is a ring without i, that is, without the requirement for an identity element.
There is no consensus in the community as to whether the existence of a multiplicative identity must be one of the ring axioms (see ). The term rng was coined to alleviate this ambiguity when people want to refer explicitly to a ring without the axiom of multiplicative identity.
A number of algebras of functions considered in analysis are not unital, for instance the algebra of functions decreasing to zero at infinity, especially those with compact support on some (non-compact) space.
Definition
Formally, a rng is a set R with two binary operations called addition and multiplication such that
(R, +) is an abelian group,
(R, ·) is a semigroup,
Multiplication distributes over addition.
A rng homomorphism is a function from one rng to another such that
f(x + y) = f(x) + f(y)
f(x · y) = f(x) · f(y)
for all x and y in R.
If R and S are rings, then a ring homomorphism is the same as a rng homomorphism that maps 1 to 1.
Examples
All rings are rngs. A simple example of a rng that is not a ring is given by the even integers with the ordinary addition and multiplication of integers. Another example is given by the set of all 3-by-3 real matrices whose bottom row is zero. Both of these examples are instances of the general fact that every (one- or two-sided) ideal is a rng.
Rngs often appear naturally in functional analysis when linear operators on infinite-dimensional vector spaces are considered. Take for instance any infinite-dimensional vector space V and consider the set of all linear operators with finite rank (i.e. ). Together with addition and composition of operators, this is a rng, but not
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https://en.wikipedia.org/wiki/WWHB-CD
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WWHB-CD (channel 48) is a low-power, Class A television station licensed to Stuart, Florida, United States, serving the West Palm Beach area with programming from the digital multicast network TBD. It is owned and operated by Sinclair Broadcast Group alongside CBS affiliate WPEC (channel 12), CW affiliate WTVX (channel 34), and Class A MyNetworkTV affiliate WTCN-CD (channel 43). The stations share studios on Fairfield Drive in Mangonia Park, Florida (with a West Palm Beach postal address), while WWHB-CD's transmitter is located southwest of Hobe Sound, Florida.
WWHB-CD is the ATSC 3.0 (Next Gen TV) transmitter for West Palm Beach, hosting its main subchannel and the four major network stations. In exchange, its subchannels are broadcast on four full-power stations in the market.
History
WWHB began broadcasting on January 11, 1991, as an independent with the call sign W16AR. It was located on UHF channel 16 and was licensed to Stuart. Retired businessman August Gabriel began the station with $200,000 and three employees. It changed its call sign to WTCN-LP in 1995. From October 1996 until February 1997, it briefly produced a local morning show known as Good Morning Treasure Coast that was hosted by Tom Teter. Ed Birchfield also briefly hosted a 7 p.m. Treasure Coast News program from February to July 1997.
The station moved to UHF channel 15 in 2001 (when it converted to Class A and changed its calls to WTCN-CA in February of that year) and then to UHF channel 14 in 2002. It added a translator on UHF channel 53 in order to reach West Palm Beach. On January 15, 2003, the station changed its calls to the current WWHB-CA and switched to UHF channel 48. This aired from a transmitter at the western boundary of Johnathan Dickinson State Park in Martin County southwest of Jupiter Island.
Martin County businessman Bill Brothers purchased the station in 2001. It was Brothers who revitalized the station creating the first Hispanic language local television service for the
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https://en.wikipedia.org/wiki/Relativity%20of%20simultaneity
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In physics, the relativity of simultaneity is the concept that distant simultaneity – whether two spatially separated events occur at the same time – is not absolute, but depends on the observer's reference frame. This possibility was raised by mathematician Henri Poincaré in 1900, and thereafter became a central idea in the special theory of relativity.
Description
According to the special theory of relativity introduced by Albert Einstein, it is impossible to say in an absolute sense that two distinct events occur at the same time if those events are separated in space. If one reference frame assigns precisely the same time to two events that are at different points in space, a reference frame that is moving relative to the first will generally assign different times to the two events (the only exception being when motion is exactly perpendicular to the line connecting the locations of both events).
For example, a car crash in London and another in New York appearing to happen at the same time to an observer on Earth, will appear to have occurred at slightly different times to an observer on an airplane flying between London and New York. Furthermore, if the two events cannot be causally connected, depending on the state of motion, the crash in London may appear to occur first in a given frame, and the New York crash may appear to occur first in another. However, if the events are causally connected, precedence order is preserved in all frames of reference.
History
In 1892 and 1895, Hendrik Lorentz used a mathematical method called "local time" t' = t – v x/c2 for explaining the negative aether drift experiments. However, Lorentz gave no physical explanation of this effect. This was done by Henri Poincaré who already emphasized in 1898 the conventional nature of simultaneity and who argued that it is convenient to postulate the constancy of the speed of light in all directions. However, this paper did not contain any discussion of Lorentz's theory or the possi
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https://en.wikipedia.org/wiki/Routhian%20mechanics
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In classical mechanics, Routh's procedure or Routhian mechanics is a hybrid formulation of Lagrangian mechanics and Hamiltonian mechanics developed by Edward John Routh. Correspondingly, the Routhian is the function which replaces both the Lagrangian and Hamiltonian functions. Routhian mechanics is equivalent to Lagrangian mechanics and Hamiltonian mechanics, and introduces no new physics. It offers an alternative way to solve mechanical problems.
Definitions
The Routhian, like the Hamiltonian, can be obtained from a Legendre transform of the Lagrangian, and has a similar mathematical form to the Hamiltonian, but is not exactly the same. The difference between the Lagrangian, Hamiltonian, and Routhian functions are their variables. For a given set of generalized coordinates representing the degrees of freedom in the system, the Lagrangian is a function of the coordinates and velocities, while the Hamiltonian is a function of the coordinates and momenta.
The Routhian differs from these functions in that some coordinates are chosen to have corresponding generalized velocities, the rest to have corresponding generalized momenta. This choice is arbitrary, and can be done to simplify the problem. It also has the consequence that the Routhian equations are exactly the Hamiltonian equations for some coordinates and corresponding momenta, and the Lagrangian equations for the rest of the coordinates and their velocities. In each case the Lagrangian and Hamiltonian functions are replaced by a single function, the Routhian. The full set thus has the advantages of both sets of equations, with the convenience of splitting one set of coordinates to the Hamilton equations, and the rest to the Lagrangian equations.
In the case of Lagrangian mechanics, the generalized coordinates , ... and the corresponding velocities , and possibly time , enter the Lagrangian,
where the overdots denote time derivatives.
In Hamiltonian mechanics, the generalized coordinates and the correspondi
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https://en.wikipedia.org/wiki/APL%20syntax%20and%20symbols
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The programming language APL is distinctive in being symbolic rather than lexical: its primitives are denoted by symbols, not words. These symbols were originally devised as a mathematical notation to describe algorithms. APL programmers often assign informal names when discussing functions and operators (for example, "product" for ×/) but the core functions and operators provided by the language are denoted by non-textual symbols.
Monadic and dyadic functions
Most symbols denote functions or operators. A monadic function takes as its argument the result of evaluating everything to its right. (Moderated in the usual way by parentheses.) A dyadic function has another argument, the first item of data on its left. Many symbols denote both monadic and dyadic functions, interpreted according to use. For example, ⌊3.2 gives 3, the largest integer not above the argument, and 3⌊2 gives 2, the lower of the two arguments.
Functions and operators
APL uses the term operator in Heaviside’s sense as a moderator of a function as opposed to some other programming language's use of the same term as something that operates on data, ref. relational operator and operators generally. Other programming languages also sometimes use this term interchangeably with function, however both terms are used in APL more precisely. Early definitions of APL symbols were very specific about how symbols were categorized. For example, the operator reduce is denoted by a forward slash and reduces an array along one axis by interposing its function operand. An example of reduce:
In the above case, the reduce or slash operator moderates the multiply function. The expression ×/2 3 4 evaluates to a scalar (1 element only) result through reducing an array by multiplication. The above case is simplified, imagine multiplying (adding, subtracting or dividing) more than just a few numbers together. (From a vector, ×/ returns the product of all its elements.)
The above dyadic functions examples [left and ri
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https://en.wikipedia.org/wiki/Allergan%2C%20Inc.
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Allergan, Inc. was an American global pharmaceutical company focused on eye care, neurosciences, medical dermatology, medical aesthetics, breast enhancement, obesity intervention and urologics. Allergan, Inc. was formed in 1948, incorporated in 1950 and became a public company in 1970. It ceased operation in 2015 when it was acquired by Irish-based Actavis plc (itself a 2013 U.S. tax inversion to Ireland), who then renamed the group as Allergan plc.
Early history
The company traces its roots back to 1948 and pharmacist Gavin S. Herbert, who in 1950 established Allergan Pharmaceuticals, Inc. Allergan focused on the discovery and development of novel formulations for specialty markets, as well as intimate collaboration with physicians and the scientific community. 1953 saw Allergan producing eye drops and formulating new products such as the first cortisone eye drop to treat allergic inflammation and the first ophthalmic steroid decongestant.
Acquisitions
Allergan became a publicly traded company in 1970 and was acquired by SmithKline for $259 million in 1980. After generating $756 million in revenue and $80 million in profit in 1988, Allergan was spun-off by SmithKline Beckman in 1989.
In July 2002, the Allergan ophthalmic surgical and contact lens care businesses were spun-off to create a new company, Advanced Medical Optics. In 2003, Allergan's flagship product, Botox, was the focus of a high-profile lawsuit and media scrutiny. In March 2006, Allergan acquired Inamed Corporation for $3 billion.
On March 1, 2013, the company acquired MAP Pharmaceuticals Inc., a development-stage company mainly researching the treatment of migraine and other oral drugs in Neurology for approximately $958 million. The principal products of this sub-company are under review with the US Food and Drug Administration (FDA). In December 2013, the company sold its obesity intervention business to Apollo Endosurgery, Inc., for a cash payment of $75 million and a $15 million minority e
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https://en.wikipedia.org/wiki/Hut%206
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Hut 6 was a wartime section of the Government Code and Cypher School (GC&CS) at Bletchley Park, Buckinghamshire, Britain, tasked with the solution of German Army and Air Force Enigma machine cyphers. Hut 8, by contrast, attacked Naval Enigma. Hut 6 was established at the initiative of Gordon Welchman, and was run initially by Welchman and fellow Cambridge mathematician John Jeffreys.
Welchman's deputy, Stuart Milner-Barry, succeeded Welchman as head of Hut 6 in September 1943, at which point over 450 people were working in the section.
Hut 6 was partnered with Hut 3, which handled the translation and intelligence analysis of the raw decrypts provided by Hut 6.
Location
Hut 6 was originally named after the building in which the section was located. Welchman says the hut was 20 yards (18m) long by 10 yards (9m) wide, with two large rooms at the far end – and no toilets. Staff had to go to another building. Irene Young recalled that she "worked in Room 82, though in typical Bletchley fashion there were not eighty-one rooms preceding it". She was glad to move from the Decoding Room "where all the operators were constantly having nervous breakdowns on account of the pace of work and the appalling noise" to the Registration Room which arranged intercepts according to callsign and frequency.
As the number of personnel increased, the section moved to additional buildings around Bletchley Park, but its name was retained, with each new location also being known as 'Hut 6'. The original building was then renamed 'Hut 16'.
Personnel
John Jeffreys was initially in charge of the Hut with Gordon Welchman until May 1940; Jeffreys was diagnosed ill in 1940, and died in 1944. Welchman became official head of section until autumn 1943, subsequently rising to Assistant Director of Mechanisation at Bletchley Park. Hugh Alexander, was a member February 1940 – March 1941 before moving to become head of Hut 8. Stuart Milner-Barry joined early 1940 and was in charge from autumn 1943
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https://en.wikipedia.org/wiki/Bristol%20stool%20scale
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The Bristol stool scale is a diagnostic medical tool designed to classify the form of human faeces into seven categories. It is used in both clinical and experimental fields.
It was developed at the Bristol Royal Infirmary as a clinical assessment tool in 1997, and is widely used as a research tool to evaluate the effectiveness of treatments for various diseases of the bowel, as well as a clinical communication aid; including being part of the diagnostic triad for irritable bowel syndrome.
Interpretation
The seven types of stool are:
Type 1: Separate hard lumps, like nuts (difficult to pass)
Type 2: Sausage-shaped, but lumpy
Type 3: Like a sausage but with cracks on its surface
Type 4: Like a sausage or snake, smooth and soft (average stool)
Type 5: Soft blobs with clear cut edges
Type 6: Fluffy pieces with ragged edges, a mushy stool (diarrhea)
Type 7: Watery, no solid pieces, entirely liquid (diarrhea)
Types 1 and 2 indicate constipation, with 3 and 4 being the ideal stools as they are easy to defecate while not containing excess liquid, 5 indicating lack of dietary fiber, and 6 and 7 indicate diarrhoea.
In the initial study, in the population examined in this scale, the type 1 and 2 stools were more prevalent in females, while the type 5 and 6 stools were more prevalent in males; furthermore, 80% of subjects who reported rectal tenesmus (sensation of incomplete defecation) had type 7. These and other data have allowed the scale to be validated. The initial research did not include a pictorial chart with this being developed at a later point.
The Bristol stool scale is also very sensitive to changes in intestinal transit time caused by medications, such as antidiarrhoeal loperamide, senna, or anthraquinone with laxative effect.
Uses
Diagnosis of irritable bowel syndrome
People with irritable bowel syndrome (IBS) typically report that they suffer with abdominal cramps and constipation.
In some patients, chronic constipation is interspersed with br
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https://en.wikipedia.org/wiki/Corresponding%20sides%20and%20corresponding%20angles
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In geometry, the tests for congruence and similarity involve comparing corresponding sides and corresponding angles of polygons. In these tests, each side and each angle in one polygon is paired with a side or angle in the second polygon, taking care to preserve the order of adjacency.
For example, if one polygon has sequential sides , , , , and and the other has sequential sides , , , , and , and if and are corresponding sides, then side (adjacent to ) must correspond to either or (both adjacent to ). If and correspond to each other, then corresponds to , corresponds to , and corresponds to ; hence the th element of the sequence corresponds to the th element of the sequence for On the other hand, if in addition to corresponding to we have corresponding to , then the th element of corresponds to the th element of the reverse sequence .
Congruence tests look for all pairs of corresponding sides to be equal in length, though except in the case of the triangle this is not sufficient to establish congruence (as exemplified by a square and a rhombus that have the same side length). Similarity tests look at whether the ratios of the lengths of each pair of corresponding sides are equal, though again this is not sufficient. In either case equality of corresponding angles is also necessary; equality (or proportionality) of corresponding sides combined with equality of corresponding angles is necessary and sufficient for congruence (or similarity). The corresponding angles as well as the corresponding sides are defined as appearing in the same sequence, so for example if in a polygon with the side sequence and another with the corresponding side sequence we have vertex angle appearing between sides and then its corresponding vertex angle must appear between sides and .
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https://en.wikipedia.org/wiki/4-Anisaldehyde
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4-Anisaldehyde, or p-Anisaldehyde, is an organic compound with the formula CH3OC6H4CHO. The molecule consists of a benzene ring with a formyl and a methoxy group. It is a colorless liquid with a strong aroma. It provides sweet, floral and strong aniseed odor. Two isomers of 4-anisaldehyde are known, ortho-anisaldehyde and meta-anisaldehyde. They are less commonly encountered.
Production
Anisaldehyde is prepared commercially by oxidation of 4-methoxytoluene (p-cresyl methyl ether) using manganese dioxide to convert a methyl group to the aldehyde group. It can also be produced by oxidation of anethole, a related fragrance that is found in some alcoholic beverages, by oxidative cleavage of an alkene.
Uses
Being structurally related to vanillin, 4-anisaldehyde is a widely used in the fragrance and flavor industry. It is used as an intermediate in the synthesis of other compounds important in pharmaceuticals and perfumery. The related ortho isomer has a scent of licorice.
A solution of para-anisaldehyde in acid and ethanol is a useful stain in thin layer chromatography. Different chemical compounds on the plate can give different colors, allowing easy distinction.
DNA breakage
Anisaldehyde in combination with copper (II) can induce single- and double-strand breaks in double stranded DNA.
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https://en.wikipedia.org/wiki/Bernie%20Krause
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Bernard L. Krause (born December 8, 1938) is an American musician and soundscape ecologist. In 1968, he founded Wild Sanctuary, an organization dedicated to the recording and archiving of natural soundscapes. Krause is an author, a bio-acoustician, a speaker, and natural sound artist who coined the terms geophony, biophony, and anthropophony.
Biography
Krause was born in Detroit, Michigan. From 1957, he worked as a recording engineer and producer in Ann Arbor while an undergraduate student. Krause joined The Weavers in 1963, occupying the tenor position originated by co-founder Pete Seeger until they disbanded in early 1964.
Electronic music
Krause moved to the San Francisco Bay Area to study electronic music at Mills College. During this period Krause met Paul Beaver and together they formed Beaver & Krause. They also served as the Moog company's sales representatives on the U.S. West Coast. As such, they were able to exploit the growing fascination in the new synthesizer sounds among rock and pop musicians, an interest that was partly influenced by these artists' consumption of hallucinogenic drugs, and the increasingly generous advances they received from their record companies. In June 1967, Beaver & Krause set up a stall at the Monterey Pop Festival, where they introduced the Moog III to the musicians and attendees at the festival.
The team played Moog synthesizer on the Monkees' song "Star Collector" (1967), one of the first pop group recordings to feature synthesizer. In 1967 they released The Nonesuch Guide to Electronic Music. It was the first West Coast recording to utilize Dolby A301 (without meters) noise reduction as an inherent part of their production. Beaver & Krause, individually or as a team, went on to sell Moog IIIs to musicians and perform on their recordings with the instrument. In November 1968 Krause was asked by George Harrison to demonstrate the synthesizer after performing on a session for Apple artist Jackie Lomax in Los Angeles. Acco
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https://en.wikipedia.org/wiki/Cinderella%20effect
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In evolutionary psychology, the Cinderella effect is the phenomenon of higher incidence of different forms of child abuse and mistreatment by stepparents than by biological parents. It takes its name from the fairy tale character Cinderella, which is about a girl who is mistreated by her stepsisters and stepmother. Evolutionary psychologists describe the effect as a byproduct of a bias towards kin, and a conflict between reproductive partners of investing in young that are unrelated to one partner.
Background
In the early 1970s, a theory arose on the connection between stepparents and child maltreatment. "In 1973, forensic psychiatrist P. D. Scott summarized information on a sample of "fatal battered-baby cases" perpetrated in anger ... 15 of the 29 killers – 52% – were stepfathers." Although initially there was no analysis of this raw data, empirical evidence has since been collected on what is now called the Cinderella effect through official records, reports, and census.
For over 30 years, data has been collected regarding the validity of the Cinderella effect, with a wealth of evidence indicating a direct relationship between step-relationships and abuse. This evidence of child abuse and homicide comes from a variety of sources including official reports of child abuse, clinical data, victim reports, and official homicide data. Studies have concluded that "stepchildren in Canada, Great Britain, and the United States indeed incur greatly elevated risk of child maltreatment of various sorts, especially lethal beatings".
Powerful evidence in support of the Cinderella effect comes from the finding that when abusive parents have both step and genetic children, they generally spare their genetic children. In such families, stepchildren were exclusively targeted 9 out of 10 times in one study and in 19 of 22 in another. In addition to displaying higher rates of negative behaviors (e.g., abuse) toward stepchildren, stepparents display fewer positive behaviors toward
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https://en.wikipedia.org/wiki/Memory-bound%20function
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Memory bound refers to a situation in which the time to complete a given computational problem is decided primarily by the amount of free memory required to hold the working data. This is in contrast to algorithms that are compute-bound, where the number of elementary computation steps is the deciding factor.
Memory and computation boundaries can sometimes be traded against each other, e.g. by saving and reusing preliminary results or using lookup tables.
Memory-bound functions and memory functions
Memory-bound functions and memory functions are related in that both involve extensive memory access, but a distinction exists between the two.
Memory functions use a dynamic programming technique called memoization in order to relieve the inefficiency of recursion that might occur. It is based on the simple idea of calculating and storing solutions to subproblems so that the solutions can be reused later without recalculating the subproblems again. The best known example that takes advantage of memoization is an algorithm that computes the Fibonacci numbers. The following pseudocode uses recursion and memoization, and runs in linear CPU time:
Fibonacci (n)
{
for i = 0 to n-1
results[i] = -1 // -1 means undefined
return Fibonacci_Results (results, n);
}
Fibonacci_Results (results, n)
{
if (results[n] != -1) // If it has been solved before,
return results[n] // look it up.
if (n == 0)
val = 0
else if (n == 1)
val = 1
else
val = Fibonacci_Results(results, n-2 ) + Fibonacci_Results(results, n-1)
results[n] = val // Save this result for re-use.
return val
}
Compare the above to an algorithm that uses only recursion, and runs in exponential CPU time:
Recursive_Fibonacci (n)
{
if (n == 0)
return 0
if (n == 1)
return 1
return Recursive_Fibonacci (n-1) + Recursive_Fibonacci (n-2)
}
While the recursive-only algorithm is simpler and more elegant
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https://en.wikipedia.org/wiki/Metabolic%20network%20modelling
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Metabolic network modelling, also known as metabolic network reconstruction or metabolic pathway analysis, allows for an in-depth insight into the molecular mechanisms of a particular organism. In particular, these models correlate the genome with molecular physiology. A reconstruction breaks down metabolic pathways (such as glycolysis and the citric acid cycle) into their respective reactions and enzymes, and analyzes them within the perspective of the entire network. In simplified terms, a reconstruction collects all of the relevant metabolic information of an organism and compiles it in a mathematical model. Validation and analysis of reconstructions can allow identification of key features of metabolism such as growth yield, resource distribution, network robustness, and gene essentiality. This knowledge can then be applied to create novel biotechnology.
In general, the process to build a reconstruction is as follows:
Draft a reconstruction
Refine the model
Convert model into a mathematical/computational representation
Evaluate and debug model through experimentation
The related method of flux balance analysis seeks to mathematically simulate metabolism in genome-scale reconstructions of metabolic networks.
Genome-scale metabolic reconstruction
A metabolic reconstruction provides a highly mathematical, structured platform on which to understand the systems biology of metabolic pathways within an organism. The integration of biochemical metabolic pathways with rapidly available, annotated genome sequences has developed what are called genome-scale metabolic models. Simply put, these models correlate metabolic genes with metabolic pathways. In general, the more information about physiology, biochemistry and genetics is available for the target organism, the better the predictive capacity of the reconstructed models. Mechanically speaking, the process of reconstructing prokaryotic and eukaryotic metabolic networks is essentially the same. Having said this,
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https://en.wikipedia.org/wiki/Microscopic%20reversibility
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The principle of microscopic reversibility in physics and chemistry is twofold:
First, it states that the microscopic detailed dynamics of particles and fields is time-reversible because the microscopic equations of motion are symmetric with respect to inversion in time (T-symmetry);
Second, it relates to the statistical description of the kinetics of macroscopic or mesoscopic systems as an ensemble of elementary processes: collisions, elementary transitions or reactions. For these processes, the consequence of the microscopic T-symmetry is: Corresponding to every individual process there is a reverse process, and in a state of equilibrium the average rate of every process is equal to the average rate of its reverse process.
History of microscopic reversibility
The idea of microscopic reversibility was born together with physical kinetics. In 1872, Ludwig Boltzmann represented kinetics of gases as statistical ensemble of elementary collisions. Equations of mechanics are reversible in time, hence, the reverse collisions obey the same laws. This reversibility of collisions is the first example of microreversibility. According to Boltzmann, this microreversibility implies the principle of detailed balance for collisions: at the equilibrium ensemble each collision is equilibrated by its reverse collision. These ideas of Boltzmann were analyzed in detail and generalized by Richard C. Tolman.
In chemistry, J. H. van't Hoff (1884) came up with the idea that equilibrium has dynamical nature and is a result of the balance between the forward and backward reaction rates. He did not study reaction mechanisms with many elementary reactions and could not formulate the principle of detailed balance for complex reactions. In 1901, Rudolf Wegscheider introduced the principle of detailed balance for complex chemical reactions. He found that for a complex reaction the principle of detailed balance implies important and non-trivial relations between reaction rate constants for dif
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https://en.wikipedia.org/wiki/Deep%20fibular%20nerve
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The deep fibular nerve (also known as deep peroneal nerve) begins at the bifurcation of the common fibular nerve between the fibula and upper part of the fibularis longus, passes infero-medially, deep to the extensor digitorum longus, to the anterior surface of the interosseous membrane, and comes into relation with the anterior tibial artery above the middle of the leg; it then descends with the artery to the front of the ankle-joint, where it divides into a lateral and a medial terminal branch.
Structure
Lateral side of the leg
The deep fibular nerve is the nerve of the anterior compartment of the leg and the dorsum of the foot. It is one of the terminal branches of the common fibular nerve. It corresponds to the posterior interosseus nerve of the forearm. It begins at the lateral side of the fibula bone, and then enters the anterior compartment by piercing the anterior intermuscular septum. It then pierces the extensor digitorum longus and lies next to the anterior tibial artery, following the course of the artery until the ankle-joint where the nerve divides into medial and lateral terminal branches. In the leg, the deep fibular nerve divides into several branches:
Muscular branches: Supplies four muscles in the leg: tibialis anterior, extensor hallucis longus, extensor digitorum longus, and fibularis tertius
Foot
Close to the ankle joint, the deep fibular nerve terminates by dividing into medial and lateral terminal branches.
Medial terminal branch: This nerve accompanies the dorsalis pedis artery along the dorsum of the foot, and, at the first interosseous space, divides into two dorsal digital nerves which supply the adjacent sides of the great and second toes, communicating with the medial dorsal cutaneous branch of the superficial fibular nerve. Before it divides it gives off to the first space an interosseous branch which supplies the metatarsophalangeal joint of the great toe and sends a filament to the first Interosseous dorsalis muscle.
Lateral t
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https://en.wikipedia.org/wiki/YIG%20sphere
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Yttrium iron garnet spheres (YIG spheres) serve as magnetically tunable filters and resonators for microwave frequencies. YIG filters are used for their high Q factors, typically between 100 and 200. A sphere made from a single crystal of synthetic yttrium iron garnet acts as a resonator.
The field from an electromagnet changes the resonance frequency of the sphere and hence the frequency it will allow to pass. The advantage of this type of filter is that the garnet can be tuned over a very wide frequency range by varying the strength of the magnetic field. Some filters can be tuned from 3 GHz up to 50 GHz.
Construction
The YIG spheres themselves are on the order of 0.5 mm in diameter and are manufactured from slightly larger cubes of diced material by tumbling, as is done in the manufacture of jewelry.
The garnet is mounted on a ceramic rod, and a pair of small loops around the sphere couple fields into and out of the sphere; the loops are half-turns, positioned at right-angles to each other to prevent direct electromagnetic coupling between them and each is grounded at one end.
The input and output coils are oriented at right angles to one another around the YIG crystal. They are cross-coupled when energized by the ferrimagnetic resonance frequency, which depends on the external magnetic field supplied by an electromagnet.
YIG filters usually consist of several coupled stages, each stage consisting of a sphere and a pair of loops.
Applications
YIG filters are often used as preselectors. YIG filters tuned by a sweep current are used in spectrum analyzers. Another YIG application is YIG oscillators, where the sphere acts as a tunable frequency-determining element. It is coupled to an amplifier which provides the required feedback for oscillation.
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https://en.wikipedia.org/wiki/Fountain%20code
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In coding theory, fountain codes (also known as rateless erasure codes) are a class of erasure codes with the property that a potentially limitless sequence of encoding symbols can be generated from a given set of source symbols such that the original source symbols can ideally be recovered from any subset of the encoding symbols of size equal to or only slightly larger than the number of source symbols. The term fountain or rateless refers to the fact that these codes do not exhibit a fixed code rate.
A fountain code is optimal if the original k source symbols can be recovered from any k successfully received encoding symbols (i.e., excluding those that were erased). Fountain codes are known that have efficient encoding and decoding algorithms and that allow the recovery of the original k source symbols from any k’ of the encoding symbols with high probability, where k’ is just slightly larger than k.
LT codes were the first practical realization of fountain codes. Raptor codes and online codes were subsequently introduced, and achieve linear time encoding and decoding complexity through a pre-coding stage of the input symbols.
Applications
Fountain codes are flexibly applicable at a fixed code rate, or where a fixed code rate cannot be determined a priori, and where efficient encoding and decoding of large amounts of data is required.
One example is that of a data carousel, where some large file is continuously broadcast to a set of receivers. Using a fixed-rate erasure code, a receiver missing a source symbol (due to a transmission error) faces the coupon collector's problem: it must successfully receive an encoding symbol which it does not already have. This problem becomes much more apparent when using a traditional short-length erasure code, as the file must be split into several blocks, each being separately encoded: the receiver must now collect the required number of missing encoding symbols for each block. Using a fountain code, it suffices for a rece
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https://en.wikipedia.org/wiki/Sharps%20waste
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Sharps waste is a form of biomedical waste composed of used "sharps", which includes any device or object used to puncture or lacerate the skin. Sharps waste is classified as biohazardous waste and must be carefully handled. Common medical materials treated as sharps waste are
hypodermic needles,
disposable scalpels and blades,
contaminated glass and certain plastics, and
guidewires used in surgery.
Qualifying materials
In addition to needles and blades, anything attached to them, such as syringes and injection devices, is also considered sharps waste.
Blades can include razors, scalpels, X-Acto knives, scissors, or any other items used for cutting in a medical or biological research setting, regardless of whether they have been contaminated with biohazardous material. While glass and sharp plastic are considered sharps waste, their handling methods can vary.
Glass items which have been contaminated with a biohazardous material are treated with the same concern as needles and blades, even if unbroken. If glass is contaminated, it is still often treated as a sharp, because it can break during the disposal process. Contaminated plastic items which are not sharp can be disposed of in a biohazardous waste receptacle instead of a sharps container.
Dangers involved
Injuries from sharps waste can pose a large public health concern, as used sharps may contain biohazardous material. It is possible for this waste to spread blood-borne pathogens if contaminated sharps penetrate the skin. The spread of these pathogens is directly responsible for the transmission of blood-borne diseases, such as hepatitis B (HBV), hepatitis C (HCV), and HIV. Health care professionals expose themselves to the risk of transmission of these diseases when handling sharps waste. The large volume handled by health care professionals on a daily basis increases the chance that an injury may occur.
The general public can occasionally be at risk of sustaining injuries from sharps waste as we
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