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https://en.wikipedia.org/wiki/Munching%20square
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The Munching Square is a display hack dating back to the PDP-1 (ca. 1962, reportedly discovered by Jackson Wright), which employs a trivial computation (repeatedly plotting the graph Y = X XOR T for successive values of T) to produce an impressive display of moving and growing squares that devour the screen. The initial value of T is treated as a parameter, which, when well-chosen, can produce amazing effects. Some of these, later (re)discovered on the LISP machine, have been christened munching triangles (using bitwise AND instead of XOR, and toggling points instead of plotting them), munching w's, and munching mazes. More generally, suppose a graphics program produces an impressive and ever-changing display of some basic form, foo, on a display terminal, and does it using a relatively simple program; then the program (or the resulting display) is likely to be referred to as munching foos.
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https://en.wikipedia.org/wiki/Mozuku
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Mozuku is a collective term for various types of Japanese brown algae from the family Chordariaceae, which are used as food. These include ito-mozuku (Nemacystus decipiens), Okinawa mozuku (Cladosiphon okamuranus), ishi-mozuku (Sphaerotrichia divaricata) and futo mozuku (Tinocladia crassa). Occasionally the aquatic flowering plant Hydrilla verticillata is referred to as mozuku.
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https://en.wikipedia.org/wiki/Backup%20site
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A backup site or work area recovery site is a location where an organization can relocate following a disaster, such as fire, flood, terrorist threat, or other disruptive event. This is an integral part of the disaster recovery plan and wider business continuity planning of an organization.
A backup, or alternate, site can be another data center location which is either operated by the organization, or contracted via a company that specializes in disaster recovery services. In some cases, one organization will have an agreement with a second organization to operate a joint backup site. In addition, an organization may have a reciprocal agreement with another organization to set up a site at each of their data centers.
Sites are generally classified based on how prepared they are and the speed with which they can be brought into operation: "cold" (facility is prepared), "warm" (equipment is in place), "hot" (operational data is loaded) –- with increasing cost to implement and maintain with increasing "temperature".
Classification
Cold site
A cold site is an empty operational space with basic facilities like raised floors, air conditioning, power and communication lines etc. Following an incident, equipment is brought in and set up to resume operations. It does not include backed-up copies of data and information from the original location of the organization, nor does it include hardware already set up. The lack of provisioned hardware contributes to the minimal start-up costs of the cold site, but requires additional time following the disaster to have the operation running at a capacity similar to that prior to the disaster. In some cases, a cold site may have equipment available, but it is not operational.
Warm site
A warm site is a compromise between hot and cold. These sites will have hardware and connectivity already established -- though on a smaller scale. Warm sites might have backups on hand, but they may be incomplete and may be between several days t
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https://en.wikipedia.org/wiki/Horizontal%20market%20software
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In computer software, horizontal market software is a type of application software that is useful in a wide range of industries. This is the opposite of vertical market software, which has a scope of usefulness limited to few industries. Horizontal market software is also known as "productivity software."
Example
Examples of horizontal market software include word processors, web browsers, spreadsheets, calendars, project management applications, and generic bookkeeping applications. Since horizontal market software is developed to be used by a broad audience, it generally lacks any market-specific customizations.
See also
Horizontal market
Vertical market software
Enterprise resource planning
Product software implementation method
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https://en.wikipedia.org/wiki/Political%20symbolism
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Political symbolism is symbolism that is used to represent a political standpoint or party.
Political symbols simplify and “summarize” the political structures and practices for which they stand; can connect institutions and beliefs with emotions; can help make a polity or political movement more cohesive. People fit themselves to words as much as they bend them to their own purposes. Different groups and individuals can interpret symbols differently because they all have the capacity to create the virtual reality within which they operate. The symbolism can occur in various media including banners, pictures, and flags. For example, Red flags have traditionally been flown by socialists, left-wing radicals, and communist groups to represent the "blood of the workers". Black flags have traditionally been flown by anarchism, and left-wing radicals to represent the absence of all oppressive structures. A combination of the two colors in a black flag represents social anarchism, such as anarchist communism and anarcho syndicalism.
Many groups use the political colour associated with their political philosophy, for example blue, particularly dark blue, is often associated with conservative parties.
Cultural groups may use symbols in what many consider to be a political way, for example LGBT symbols like the Rainbow flag are used to promote the political goal of LGBT rights.
Individual parties often associate, officially or unofficially, with symbols — sometimes adopting or incorporating symbolism associated with ideologies they support. In some democracies these symbols are regulated by law, for example, in the United Kingdom, political symbols are regulated by the Electoral Commission. In some countries, political symbols appear on ballot papers. These are known as electoral symbols and one of their functions is to help illiterate voters identify parties.
See also
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https://en.wikipedia.org/wiki/Fully%20switched%20network
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A fully switched network is a computer network which uses only network switches rather than Ethernet hubs on Ethernet networks. The switches provide a dedicated connection to each workstation. A switch allows for many conversations to occur simultaneously. Before switches, networks based on hubs data could only allow transmission in one direction at a time, this was called half-duplex. By using a switch this restriction is removed; full-duplex communication is maintained and the network is collision free. This means that data can now be transmitted in both directions at the same time. Fully switched networks employ either twisted-pair or fiber-optic cabling, both of which use separate conductors for sending and receiving data. In this type of environment, Ethernet nodes can forgo the collision detection process and transmit at will, since they are the only potential devices that can access the medium. This means that a fully switched network is a collision-free environment.
The core function of a switch is to allow each workstation to communicate only with the switch instead of with each other. This in turn means that data can be sent from workstation to switch and from switch to workstation simultaneously. The core purpose of a switch is to decongest network flow to the workstations so that the connections can transmit more effectively; receiving transmissions that were only specific to their network address. With the network decongested and transmitting data in both directions simultaneously this can in fact double network speed and capacity when two workstations are trading information. For example, if your network speed is 5 Mbit/s, then each workstation is able to simultaneously transfer data at 5 Mbit/s.
See also
Network performance
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https://en.wikipedia.org/wiki/Bhaskaracharya%20Pratishthana
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Bhaskaracharya Pratishthana is a research and education institute for mathematics in Pune, India, founded by noted Indian-American mathematician professor Shreeram Abhyankar.
The institute is named after the great ancient Indian Mathematician Bhaskaracharya (Born in 1114 A.D.). Bhaskaracharya Pratishthana is a Pune, India, based institute founded in 1976. It has researchers working in many areas of mathematics, particularly in algebra and number theory.
Since 1992, the Pratishthan has also been a recognized center for conducting Regional Mathematics Olympiad (RMO) under the National Board for Higher Mathematics (NBHM) for Maharashtra and Goa Region. This has enabled the Pratishthan to train lots of students from std. V to XII for this examination. Many students who received training at BP have won medals in the International Mathematical Olympiad.
Pratishthana publishes the mathematics periodical Bona Mathematica and has published texts in higher and olympiad mathematics. Besides this the Pratishthan holds annual / biennial conferences/Workshops in some research areas in higher mathematics attended by Indian/Foreign scholars and Professors. The Pratishthan has organized a number of workshops for research students and college teachers under the aegis of NBHM/NCM. The National Board for Higher Mathematics has greatly helped Pratishthan to enrich its library and the Department of Atomic Energy and the Mathematics Department of S. P. Pune University have rendered active co-operation in holding conferences/workshops.
It also conducts the BMTSC exam which is a school-level mathematics competition for students studying in the 5th and the 6th grade. The objectives of the competition are listed below:
1. Identify good students of mathematics at an early age.
2. A pre Olympiad type competition.
3. To enhance Mathematical ability and logical thinking.
4. Nurture programs for successful students to improve their ability.
Projects
Recently, in Pratishthana, two projects supp
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https://en.wikipedia.org/wiki/TGF%20beta%20signaling%20pathway
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The transforming growth factor beta (TGFB) signaling pathway is involved in many cellular processes in both the adult organism and the developing embryo including cell growth, cell differentiation, cell migration, apoptosis, cellular homeostasis and other cellular functions. The TGFB signaling pathways are conserved. In spite of the wide range of cellular processes that the TGFβ signaling pathway regulates, the process is relatively simple. TGFβ superfamily ligands bind to a type II receptor, which recruits and phosphorylates a type I receptor. The type I receptor then phosphorylates receptor-regulated SMADs (R-SMADs) which can now bind the coSMAD SMAD4. R-SMAD/coSMAD complexes accumulate in the nucleus where they act as transcription factors and participate in the regulation of target gene expression.
Mechanism
Ligand binding
The TGF beta superfamily of ligands includes: Bone morphogenetic proteins (BMPs), Growth and differentiation factors (GDFs), Anti-müllerian hormone (AMH), Activin, Nodal and TGFβs. Signaling begins with the binding of a TGF beta superfamily ligand to a TGF beta type II receptor. The type II receptor is a serine/threonine receptor kinase, which catalyzes the phosphorylation of the Type I receptor. Each class of ligand binds to a specific type II receptor. In mammals there are seven known type I receptors and five type II receptors.
There are three activins: Activin A, Activin B and Activin AB. Activins are involved in embryogenesis and osteogenesis. They also regulate many hormones including pituitary, gonadal and hypothalamic hormones as well as insulin. They are also nerve cell survival factors.
The BMPs bind to the bone morphogenetic protein receptor type-2 (BMPR2). They are involved in a multitude of cellular functions including osteogenesis, cell differentiation, anterior/posterior axis specification, growth, and homeostasis.
The TGFβ family includes: TGFβ1, TGFβ2, TGFβ3. Like the BMPs, TGFβs are involved not only in embryogenesis a
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https://en.wikipedia.org/wiki/Germinal%20matrix
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In anatomy, the germinal matrix is a highly cellular and highly vascularized region in the brain out from which cells migrate during brain development. The germinal matrix is the source of both neurons and glial cells and is most active between 8 and 28 weeks gestation. It is a fragile portion of the brain that may be damaged leading to a germinal matrix hemorrhage (grade 1 intraventricular hemorrhage).
Location/anatomy: The germinal matrix is next to the lateral ventricles (the "inside" of the brain).
Function/physiology: Neurons and glia migrate radially outward from the germinal matrix towards the cerebral cortex. For more information, see the associated articles on neuronal migration and corticogenesis.
Dysfunction/pathophysiology: in prenatology/neonatology, intraventricular hemorrhages occur starting in the germinal matrix due to the lack of structural integrity there. Intraventricular hemorrhages are a common and harmful issue in children born prematurely.
See also
Intraventricular hemorrhage
Ganglionic eminence
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https://en.wikipedia.org/wiki/Versatile%20Toroidal%20Facility
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The Versatile Toroidal Facility (VTF) is a research group within the Physics Research Division of the MIT Plasma Science and Fusion Center at the Massachusetts Institute of Technology. The VTF is a laboratory focused on studying the phenomenon of magnetic reconnection. For this purpose the group has a small tokamak designed to observe rarefied plasmas with probes. These probes measure electric and magnetic field behavior as well as various plasma characteristics in order to better understand the poorly understood processes involved in magnetic reconnection.
The VTF is a fundamental physics research group, and its research has wide-ranging and immediate impact on our understanding of such plasma-related subjects as solar flares, the aurora borealis, magnetic confinement fusion, and magnetohydrodynamic theory in general. The VTF is was built and originally led by Dr. Marcel Gaudreau, and prior to its retirement, was led by Dr. Miklos Porkolab and Dr. Jan Egedal, all MIT faculty at the time.
External links
PSFC homepage
VTF homepage
Massachusetts Institute of Technology
Plasma physics facilities
Tokamaks
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https://en.wikipedia.org/wiki/Family%20of%20curves
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In geometry, a family of curves is a set of curves, each of which is given by a function or parametrization in which one or more of the parameters is variable. In general, the parameter(s) influence the shape of the curve in a way that is more complicated than a simple linear transformation. Sets of curves given by an implicit relation may also represent families of curves.
Families of curves appear frequently in solutions of differential equations; when an additive constant of integration is introduced, it will usually be manipulated algebraically until it no longer represents a simple linear transformation.
Families of curves may also arise in other areas. For example, all non-degenerate conic sections can be represented using a single polar equation with one parameter, the eccentricity of the curve:
as the value of changes, the appearance of the curve varies in a relatively complicated way.
Applications
Families of curves may arise in various topics in geometry, including the envelope of a set of curves and the caustic of a given curve.
Generalizations
In algebraic geometry, an algebraic generalization is given by the notion of a linear system of divisors.
External links
Algebraic geometry
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https://en.wikipedia.org/wiki/Coastal%20zone%20color%20scanner
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The coastal zone color scanner (CZCS) was a multi-channel scanning radiometer aboard the Nimbus 7 satellite, predominately designed for water remote sensing. Nimbus 7 was launched 24 October 1978, and CZCS became operational on 2 November 1978. It was only designed to operate for one year (as a proof-of-concept), but in fact remained in service until 22 June 1986. Its operation on board the Nimbus 7 was limited to alternate days as it shared its power with the passive microwave scanning multichannel microwave radiometer.
CZCS measured reflected solar energy in six channels, at a resolution of 800 meters. These measurements were used to map chlorophyll concentration in water, sediment distribution, salinity, and the temperature of coastal waters and ocean currents.
CZCS lay the foundations for subsequent satellite ocean color sensors, and formed a cornerstone for international efforts to understand the ocean's role in the carbon cycle.
Ocean color
The most significant product of the CZCS was its collection of so-called ocean color imagery. The "color" of the ocean in CZCS images comes from substances in the water, particularly phytoplankton (microscopic, free-floating photosynthetic organisms), as well as inorganic particulates.
Because ocean color data is related to the presence of phytoplankton and particulates, it can be used to calculate the concentrations of material in surface waters and the level of biological activity; as phytoplankton concentration increases, ocean color shifts from blue to green (note that most CZCS images are false colored, so that high levels of phytoplankton appear as red or orange). Satellite-based ocean color observations provide a global picture of life in the world's oceans, because phytoplankton is the basis for the vast majority of oceanic food chains. By recording images over a period of years, scientists also gained a better understanding of how the phytoplankton biomass changed over time; for instance, red tide blooms
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https://en.wikipedia.org/wiki/Cognitive%20dimensions%20of%20notations
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Cognitive dimensions or cognitive dimensions of notations are design principles for notations, user interfaces and programming languages, described by researcher Thomas R.G. Green and further researched with Marian Petre. The dimensions can be used to evaluate the usability of an existing information artifact, or as heuristics to guide the design of a new one, and are useful in Human-Computer Interaction design.
Cognitive dimensions are designed to provide a lightweight approach to analyse the quality of a design, rather than an in-depth, detailed description. They provide a common vocabulary for discussing many factors in notation, UI or programming language design. Also, cognitive dimensions help in exploring the space of possible designs through design maneuvers, changes intended to improve the design along one dimension.
List of the cognitive dimensions
Thomas Green originally defined 14 cognitive dimensions:
Abstraction gradient What are the minimum and maximum levels of abstraction exposed by the notation? Can details be encapsulated?
Closeness of mapping How closely does the notation correspond to the problem world?
Consistency After part of the notation has been learned, how much of the rest can be successfully guessed?
Diffuseness / terseness How many symbols or how much space does the notation require to produce a certain result or express a meaning?
Error-proneness To what extent does the notation influence the likelihood of the user making a mistake?
Hard mental operations How much hard mental processing lies at the notational level, rather than at the semantic level? Are there places where the user needs to resort to fingers or penciled annotation to keep track of what's happening?
Hidden dependencies Are dependencies between entities in the notation visible or hidden? Is every dependency indicated in both directions? Does a change in one area of the notation lead to unexpected consequences?
Juxtaposability Can different par
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https://en.wikipedia.org/wiki/Secondary%20notation
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Secondary notation is the set of visual cues used to improve the readability of a formal notation. Examples of secondary notation include the syntax highlighting of computer source code, sizes and color codes for easy recognition of consumer symbols such as bank notes or coins, or the regular typographic conventions often found in technical books to highlight sections with the same type of content.
Secondary notation provides redundant (more than necessary) information; if the visual cues are the only way that some information is provided, such as in traffic lights, or a chart's key, it is not secondary. Secondary notation is often not a part of the formal notation itself. Rather, it is a method of organizing the formal notation to allow it to be more easily understood. Thus, secondary notation does not change the actual meaning of the formal notation, rather it allows for the meaning to be readily understood. In text such as programming languages, this can be done using cues such as indentation and coloring. In formal graphical notations, this can be done through the use of symmetry or proximity to indicate relatedness.
In different contexts
Secondary notation annotates formal notation in a number of contexts which can be broken down to two main domains: text and graphics.
Textual context
There are a number of common instances of secondary notation that are seen in text. Secondary notation is common in typography and in code editors appearing as boldness, italics, and spacing/indentation.
Textual secondary notation in computer source code
Secondary notation in the form of coloring and indentation is commonly implemented in integrated development environments to make source code more readable and make the formal notation more understandable. The following C source code does not use secondary notation to ease the interpretation of the formal notation:
int main(){while(true){printf("I'm stuck in an infinite loop!");}}
The following is the same code, but with
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https://en.wikipedia.org/wiki/Lamina%20%28algae%29
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The lamina or blade in macroscopic algae like seaweed is a generally flattened structure that typically forms the principal bulk of the thallus. It is often developed into specialised organs such as flotation bladders and reproductive organs.
The lamina is typically an expansion of the stipe which in term is attached to the substrate by the holdfast.
Brown algae
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https://en.wikipedia.org/wiki/Chopsticks%20%28hand%20game%29
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Chopsticks (sometimes called Calculator, or just Sticks) is a hand game for two or more players, in which players extend a number of fingers from each hand and transfer those scores by taking turns to tap one hand against another. Chopsticks is an example of a combinatorial game, and is solved in the sense that with perfect play, an optimal strategy from any point is known.
If you have the same number of fingers on each hand you can strike them together and divide them leaving you with one finger on each hand.
When the player only has one finger left it can not be swapped between hands and must attack the opponent.
Abbreviation
A chopsticks position can be easily abbreviated to a four-digit code [ABCD]. A and B are the hands (in ascending order of fingers) of the player who is about to take their turn. C and D are the hands (in ascending order of fingers) of the player who is not about to take their turn. It is important to notate each player's hands in ascending order, so that a single distinct position isn't accidentally represented by two codes. For example, the code [1032] is not allowed, and should be notated [0123].
Therefore, the starting position is [1111]. The next position must be [1211]. The next position must be either [1212] or [1312]. Treating each position as a 4-digit number, the smallest position is 0000, and the largest position is 4444.
This abbreviation formula expands easily to games with more players. A three-player game can be represented by six-digits (e.g. [111211]), where each pair of adjacent digits represents a single player, and each pair is ordered based on when players will take their turns. The leftmost pair represents the hands of the player about to take his turn; the middle pair represents the player who will go next, and so on. The rightmost pair represents the player who must wait the longest before his turn (usually because he just went).
Moves
Under normal rules, there are a maximum of 14 possible moves:
Four attacks (
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https://en.wikipedia.org/wiki/Junkyard%20tornado
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The junkyard tornado, sometimes known as Hoyle's fallacy, is an argument against abiogenesis, using a calculation of its probability based on false assumptions, as comparable to "a tornado sweeping through a junk-yard might assemble a Boeing 747 from the materials therein" and to compare the chance of obtaining even a single functioning protein by chance combination of amino acids to a solar system full of blind men solving Rubik's Cubes simultaneously. It was used originally by English astronomer Fred Hoyle (1915–2001) in his book The Intelligent Universe, where he tried to apply statistics to evolution and the origin of life. Similar reasoning were advanced in Darwin's time, and indeed as long ago as Cicero in classical antiquity. While Hoyle himself was an atheist, the argument has since become a mainstay in the rejection of evolution by religious groups.
Hoyle's fallacy contradicts many well-established and widely tested principles in the field of evolutionary biology. As the fallacy argues, the odds of the sudden construction of higher lifeforms are indeed improbable. However, what the junkyard tornado postulation fails to take into account is the vast amount of support that evolution proceeds in many smaller stages, each driven by natural selection rather than by random chance, over a long period of time. The Boeing 747 was not designed in a single unlikely burst of creativity, just as modern lifeforms were not constructed in one single unlikely event, as the junkyard tornado scenario suggests.
The theory of evolution has been studied and tested extensively by numerous researchers and scientists and is the most scientifically accurate explanation for the origins of complex life.
Hoyle's statement
According to Fred Hoyle's analysis, the probability of obtaining all of life's approximate 2000 enzymes in a random trial is about one-in-1040,000:
His junkyard analogy:
This echoes his stance, reported elsewhere:
Hoyle used this to argue in favor of panspermia
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https://en.wikipedia.org/wiki/Mean%20absolute%20difference
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The mean absolute difference (univariate) is a measure of statistical dispersion equal to the average absolute difference of two independent values drawn from a probability distribution. A related statistic is the relative mean absolute difference, which is the mean absolute difference divided by the arithmetic mean, and equal to twice the Gini coefficient.
The mean absolute difference is also known as the absolute mean difference (not to be confused with the absolute value of the mean signed difference) and the Gini mean difference (GMD). The mean absolute difference is sometimes denoted by Δ or as MD.
Definition
The mean absolute difference is defined as the "average" or "mean", formally the expected value, of the absolute difference of two random variables X and Y independently and identically distributed with the same (unknown) distribution henceforth called Q.
Calculation
Specifically, in the discrete case,
For a random sample of size n of a population distributed uniformly according to Q, by the law of total expectation the (empirical) mean absolute difference of the sequence of sample values yi, i = 1 to n can be calculated as the arithmetic mean of the absolute value of all possible differences:
if Q has a discrete probability function f(y), where yi, i = 1 to n, are the values with nonzero probabilities:
In the continuous case,
if Q has a probability density function f(x):
An alternative form of the equation is given by:
if Q has a cumulative distribution function F(x) with quantile function Q(F), then, since f(x)=dF(x)/dx and Q(F(x))=x, it follows that:
Relative mean absolute difference
When the probability distribution has a finite and nonzero arithmetic mean AM, the relative mean absolute difference, sometimes denoted by Δ or RMD, is defined by
The relative mean absolute difference quantifies the mean absolute difference in comparison to the size of the mean and is a dimensionless quantity. The relative mean absolute difference is eq
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https://en.wikipedia.org/wiki/Protylopus
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Protylopus is an extinct genus of camel that lived during middle to late Eocene some 50-40 million years ago in North America.
Along with being the oldest camel known, it was also the smallest, reaching a length of , and probably weighing around . Based on its teeth, it probably fed on the soft leaves of forest plants. Protylopus's front legs were shorter than the hind legs, and ended in four-toed feet. The hind legs also ended in four toes, but most of the weight was carried by the third and fourth, so it may have raised itself up on its back legs like the modern day gerenuk antelope to feed. The shape of the toes suggests that the animal possessed hooves, rather than the foot-pads of modern camels.
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https://en.wikipedia.org/wiki/Ehresmann%20connection
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In differential geometry, an Ehresmann connection (after the French mathematician Charles Ehresmann who first formalized this concept) is a version of the notion of a connection, which makes sense on any smooth fiber bundle. In particular, it does not rely on the possible vector bundle structure of the underlying fiber bundle, but nevertheless, linear connections may be viewed as a special case. Another important special case of Ehresmann connections are principal connections on principal bundles, which are required to be equivariant in the principal Lie group action.
Introduction
A covariant derivative in differential geometry is a linear differential operator which takes the directional derivative of a section of a vector bundle in a covariant manner. It also allows one to formulate a notion of a parallel section of a bundle in the direction of a vector: a section s is parallel along a vector X if . So a covariant derivative provides at least two things: a differential operator, and a notion of what it means to be parallel in each direction. An Ehresmann connection drops the differential operator completely and defines a connection axiomatically in terms of the sections parallel in each direction . Specifically, an Ehresmann connection singles out a vector subspace of each tangent space to the total space of the fiber bundle, called the horizontal space. A section s is then horizontal (i.e., parallel) in the direction X if lies in a horizontal space. Here we are regarding s as a function from the base M to the fiber bundle E, so that is then the pushforward of tangent vectors. The horizontal spaces together form a vector subbundle of .
This has the immediate benefit of being definable on a much broader class of structures than mere vector bundles. In particular, it is well-defined on a general fiber bundle. Furthermore, many of the features of the covariant derivative still remain: parallel transport, curvature, and holonomy.
The missing ingredient
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https://en.wikipedia.org/wiki/Van%20Hiele%20model
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In mathematics education, the Van Hiele model is a theory that describes how students learn geometry. The theory originated in 1957 in the doctoral dissertations of Dina van Hiele-Geldof and Pierre van Hiele (wife and husband) at Utrecht University, in the Netherlands. The Soviets did research on the theory in the 1960s and integrated their findings into their curricula. American researchers did several large studies on the van Hiele theory in the late 1970s and early 1980s, concluding that students' low van Hiele levels made it difficult to succeed in proof-oriented geometry courses and advising better preparation at earlier grade levels. Pierre van Hiele published Structure and Insight in 1986, further describing his theory. The model has greatly influenced geometry curricula throughout the world through emphasis on analyzing properties and classification of shapes at early grade levels. In the United States, the theory has influenced the geometry strand of the Standards published by the National Council of Teachers of Mathematics and the Common Core Standards.
Van Hiele levels
The student learns by rote to operate with [mathematical] relations that he does not understand, and of which he has not seen the origin…. Therefore the system of relations is an independent construction having no rapport with other experiences of the child. This means that the student knows only what has been taught to him and what has been deduced from it. He has not learned to establish connections between the system and the sensory world. He will not know how to apply what he has learned in a new situation. - Pierre van Hiele, 1959
The best known part of the van Hiele model are the five levels which the van Hieles postulated to describe how children learn to reason in geometry. Students cannot be expected to prove geometric theorems until they have built up an extensive understanding of the systems of relationships between geometric ideas. These systems cannot be learned by rote, but
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https://en.wikipedia.org/wiki/Arnold%27s%20cat%20map
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In mathematics, Arnold's cat map is a chaotic map from the torus into itself, named after Vladimir Arnold, who demonstrated its effects in the 1960s using an image of a cat, hence the name.
Thinking of the torus as the quotient space , Arnold's cat map is the transformation given by the formula
Equivalently, in matrix notation, this is
That is, with a unit equal to the width of the square image, the image is sheared one unit up, then two units to the right, and all that lies outside that unit square is shifted back by the unit until it is within the square.
Properties
Γ is invertible because the matrix has determinant 1 and therefore its inverse has integer entries,
Γ is area preserving,
Γ has a unique hyperbolic fixed point (the vertices of the square). The linear transformation which defines the map is hyperbolic: its eigenvalues are irrational numbers, one greater and the other smaller than 1 (in absolute value), so they are associated respectively to an expanding and a contracting eigenspace which are also the stable and unstable manifolds. The eigenspaces are orthogonal because the matrix is symmetric. Since the eigenvectors have rationally independent components both the eigenspaces densely cover the torus. Arnold's cat map is a particularly well-known example of a hyperbolic toral automorphism, which is an automorphism of a torus given by a square unimodular matrix having no eigenvalues of absolute value 1.
The set of the points with a periodic orbit is dense on the torus. Actually a point is periodic if and only if its coordinates are rational.
Γ is topologically transitive (i.e. there is a point whose orbit is dense).
The number of points with period is exactly (where and are the eigenvalues of the matrix). For example, the first few terms of this series are 1, 5, 16, 45, 121, 320, 841, 2205 .... (The same equation holds for any unimodular hyperbolic toral automorphism if the eigenvalues are replaced.)
Γ is ergodic and mixing,
Γ is an Ano
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https://en.wikipedia.org/wiki/Perceived%20performance
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Perceived performance, in computer engineering, refers to how quickly a software feature appears to perform its task. The concept applies mainly to user acceptance aspects.
The amount of time an application takes to start up, or a file to download, is not made faster by showing a startup screen (see Splash screen) or a file progress dialog box. However, it satisfies some human needs: it appears faster to the user as well as providing a visual cue to let them know the system is handling their request.
In most cases, increasing real performance increases perceived performance, but when real performance cannot be increased due to physical limitations, techniques can be used to increase perceived performance at the cost of marginally decreasing real performance. For example, drawing and refreshing a progress bar while loading a file satisfies the user who is watching, but steals time from the process that is actually loading the file, but usually this is only a very small amount of time. All such techniques must exploit the inability of the user to accurately judge real performance, or they would be considered detrimental to performance.
Techniques for improving perceived performance may include more than just decreasing the delay between the user's request and visual feedback. Sometimes an increase in delay can be perceived as a performance improvement, such as when a variable controlled by the user is set to a running average of the users input. This can give the impression of smoother motion, but the controlled variable always reaches the desired value a bit late. Since it smooths out hi-frequency jitter, when the user is attempting to hold the value constant, they may feel like they are succeeding more readily. This kind of compromise would be appropriate for control of a sniper rifle in a video game. Another example may be doing trivial computation ahead of time rather than after a user triggers an action, such as pre-sorting a large list of data before a user w
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https://en.wikipedia.org/wiki/MUSCL%20scheme
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In the study of partial differential equations, the MUSCL scheme is a finite volume method that can provide highly accurate numerical solutions for a given system, even in cases where the solutions exhibit shocks, discontinuities, or large gradients. MUSCL stands for Monotonic Upstream-centered Scheme for Conservation Laws (van Leer, 1979), and the term was introduced in a seminal paper by Bram van Leer (van Leer, 1979). In this paper he constructed the first high-order, total variation diminishing (TVD) scheme where he obtained second order spatial accuracy.
The idea is to replace the piecewise constant approximation of Godunov's scheme by reconstructed states, derived from cell-averaged states obtained from the previous time-step. For each cell, slope limited, reconstructed left and right states are obtained and used to calculate fluxes at the cell boundaries (edges). These fluxes can, in turn, be used as input to a Riemann solver, following which the solutions are averaged and used to advance the solution in time. Alternatively, the fluxes can be used in Riemann-solver-free schemes, which are basically Rusanov-like schemes.
Linear reconstruction
We will consider the fundamentals of the MUSCL scheme by considering the following simple first-order, scalar, 1D system, which is assumed to have a wave propagating in the positive direction,
Where represents a state variable and represents a flux variable.
The basic scheme of Godunov uses piecewise constant approximations for each cell, and results in a first-order upwind discretisation of the above problem with cell centres indexed as . A semi-discrete scheme can be defined as follows,
This basic scheme is not able to handle shocks or sharp discontinuities as they tend to become smeared. An example of this effect is shown in the diagram opposite, which illustrates a 1D advective equation with a step wave propagating to the right. The simulation was carried out with a mesh of 200 cells and used a 4th order Run
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https://en.wikipedia.org/wiki/Gluteome
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The term gluteome is used to describe the entire set of all gluten-like proteins in grains, which consumption causes occurrence of clinical manifestations in celiac patients. These proteins include gliadins and glutenins from wheat, secalins from rye, hordeins from barley, avenins from oats and potentially homologues from other related grain species. Since not all grain storage proteins have been identified yet, the term gluteome often refers to the complete set of the known sequences of gluten and gluten-like molecules.
Alternatively, the word gluteome can depict the entire complement of grain-storage proteins in a single grain species at a given time.
The discipline of science dedicated to study gluteome is referred to as gluteomics.
Gluten
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https://en.wikipedia.org/wiki/Gingerbreadman%20map
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In dynamical systems theory, the Gingerbreadman map is a chaotic two-dimensional map. It is given by the piecewise linear transformation:
See also
List of chaotic maps
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https://en.wikipedia.org/wiki/Storage%20violation
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In computing a storage violation is a hardware or software fault that occurs when a task attempts to access an area of computer storage which it is not permitted to access.
Types of storage violation
Storage violation can, for instance, consist of reading from, writing to, or freeing storage not owned by the task. A common type of storage violation is known as a stack buffer overflow where a program attempts to exceed the limits set for its call stack. It can also refer to attempted modification of memory "owned" by another thread where there is incomplete (or no) memory protection.
Avoidance of storage violations
Storage violations can occur in transaction systems such as CICS in circumstances where it is possible to write to storage not owned by the transaction; such violations can be reduced by enabling features such as storage protection and transaction isolation.
Detection of storage violations
Storage violations can be difficult to detect as a program can often run for a period of time after the violation before it crashes. For example, a pointer to a freed area of memory can be retained and later reused causing an error. As a result, efforts focus on detecting violations as they occur, rather than later when the problem is observed.
In systems such as CICS, storage violations are sometimes detected (by the CICS kernel) by the use of "signatures", which can be tested to see if they have been overlaid.
An alternative runtime library may be used to better detect storage violations, at the cost of additional overhead.
Some programming languages use software bounds checking to prevent these occurrences.
Some program debugging software will also detect violations during testing.
Common causes
A runaway subscript leading to illegal use of reference modification during run time.
Linkage layout mismatch between called and the calling elements.
Use of previously freed (and sometimes already re-allocated) memory.
Examples of software detecting storage violati
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https://en.wikipedia.org/wiki/Stewart%27s%20theorem
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In geometry, Stewart's theorem yields a relation between the lengths of the sides and the length of a cevian in a triangle. Its name is in honour of the Scottish mathematician Matthew Stewart, who published the theorem in 1746.
Statement
Let , , be the lengths of the sides of a triangle. Let be the length of a cevian to the side of length . If the cevian divides the side of length into two segments of length and , with adjacent to and adjacent to , then Stewart's theorem states that
A common mnemonic used by students to memorize this equation (after rearranging the terms) is:
The theorem may be written more symmetrically using signed lengths of segments. That is, take the length to be positive or negative according to whether is to the left or right of in some fixed orientation of the line. In this formulation, the theorem states that if are collinear points, and is any point, then
In the special case that the cevian is the median (that is, it divides the opposite side into two segments of equal length), the result is known as Apollonius' theorem.
Proof
The theorem can be proved as an application of the law of cosines.
Let be the angle between and and the angle between and . Then is the supplement of , and so . Applying the law of cosines in the two small triangles using angles and produces
Multiplying the first equation by and the third equation by and adding them eliminates . One obtains
which is the required equation.
Alternatively, the theorem can be proved by drawing a perpendicular from the vertex of the triangle to the base and using the Pythagorean theorem to write the distances , , in terms of the altitude. The left and right hand sides of the equation then reduce algebraically to the same expression.
History
According to , Stewart published the result in 1746 when he was a candidate to replace Colin Maclaurin as Professor of Mathematics at the University of Edinburgh. state that the result was probably known to Arc
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https://en.wikipedia.org/wiki/Cheat%20sheet
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A cheat sheet (also cheatsheet) or crib sheet is a concise set of notes used for quick reference. Cheat sheets were historically used by students without an instructor or teacher's knowledge to cheat on a test or exam. In the context of higher education or vocational training, where rote memorization is not as important, students may be permitted (or even encouraged) to develop and consult their cheat sheets during exams. The act of preparing such reference notes can be an educational exercise in itself, in which case students may be restricted to using only those reference notes they have developed themselves. Some universities publish guidelines for the creation of cheat sheets.
As reference cards
In more general usage, a crib sheet is any short (one- or two-page) reference to terms, commands, or symbols where the user is expected to understand the use of such terms but not necessarily to have memorized all of them. Many computer applications, for example, have crib sheets included in their documentation, which list keystrokes or menu commands needed to achieve specific tasks to save the user the effort of digging through an entire manual to find the keystroke needed to, for example, move between two windows. An example of such a crib sheet is one for the GIMP photo editing software.
See also
Academic dishonesty
Reference card
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https://en.wikipedia.org/wiki/Babesia
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Babesia, also called Nuttallia, is an apicomplexan parasite that infects red blood cells and is transmitted by ticks. Originally discovered by the Romanian bacteriologist Victor Babeș in 1888, over 100 species of Babesia have since been identified.
Babesia comprises more than 100 species of tick-borne parasites that infect erythrocytes (red blood cells) in many vertebrate hosts.
Babesia species infect livestock worldwide, wild and domestic vertebrate animals, and occasionally humans, where they cause the disease babesiosis. In the United States, B. microti is the most common strain of the few which have been documented to cause disease in humans.
Classification
Babesia is a protozoan parasite found to infect vertebrate animals, mostly livestock mammals and birds, but also occasionally humans. Common names of the disease that Babesia microti causes are Texas cattle fever, redwater fever, tick fever, and Nantucket fever. The disease it causes in humans, babesiosis, is also called piroplasmosis.
Babesia microti, however, is not part of the genus Babesia. Due to historical misclassifications, the protozoan has been labeled with many names, including Nuttallia, and was renamed from Babesia microti to Theileria microti based on evidence from 2006. Its genetic sequence, published in 2012, shows that the species belongs to neither Babesia nor Theileria, but instead to a separate genus. Another "western" group is also separate from core Babesia.
The avian Babesia species are characterized as having ring and amoeboid forms, and fan-shaped or cruciform (cross-shaped) tetrad schizonts. Developing parasites have only been reported in red blood cells.
History
For centuries, the animal disease was known to be a serious illness for wild and domesticated animals, especially cattle. In 1888, Victor Babeș first identified the causative agent in Romania and believed it to be due to the bacterium he named Haematococcus bovis. He documented the disease by describing signs of a s
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https://en.wikipedia.org/wiki/High-%20and%20low-level
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High-level and low-level, as technical terms, are used to classify, describe and point to specific goals of a systematic operation; and are applied in a wide range of contexts, such as, for instance, in domains as widely varied as computer science and business administration.
High-level describe those operations that are more abstract and general in nature; wherein the overall goals and systemic features are typically more concerned with the wider, macro system as a whole.
Low-level describes more specific individual components of a systematic operation, focusing on the details of rudimentary micro functions rather than macro, complex processes. Low-level classification is typically more concerned with individual components within the system and how they operate.
Features which emerge only at a high level of description are known as epiphenomena.
Differences
Due to the nature of complex systems, the high-level description will often be completely different from the low-level one; and, therefore, the (different) descriptions that each deliver are consequent upon the level at which each (differently) direct their study. For example,
there are features of an ant colony that are not features of any individual ant;
there are features of the human mind that are not known to be descriptive of individual neurons in the brain;
there are features of oceans which are not features of any individual water molecule; and
there are features of a human personality that are not features of any cell in a body.
Uses
In computer science, software is typically divided into two types: high-level end-user applications software (such as word processors, databases, video games, etc.), and low-level systems software (such as operating systems, hardware drivers, etc.).As such, high-level applications typically rely on low-level applications to function.In terms of programming, a high-level programming language is one which has a relatively high level of abstraction, and manipulates c
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https://en.wikipedia.org/wiki/General-purpose%20modeling
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General-purpose modeling (GPM) is the systematic use of a general-purpose modeling language to represent the various facets of an object or a system. Examples of GPM languages are:
The Unified Modeling Language (UML), an industry standard for modeling software-intensive systems
EXPRESS, a data modeling language for product data, standardized as ISO 10303-11
IDEF, a group of languages from the 1970s that aimed to be neutral, generic and reusable
Gellish, an industry standard natural language oriented modeling language for storage and exchange of data and knowledge, published in 2005
XML, a data modeling language now beginning to be used to model code (MetaL, Microsoft .Net )
GPM languages are in contrast with domain-specific modeling languages (DSMs).
See also
Model-driven engineering (MDE)
Specification languages
Modeling languages
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https://en.wikipedia.org/wiki/Geranyl%20acetate
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Geranyl acetate is a monoterpene. It is a colorless liquid with a pleasant floral or fruity rose aroma. It is a colorless liquid but commercial samples can appear yellowish. Geranyl acetate is insoluble in water but soluble in organic solvents. Several hundred tons are produced annually.
Occurrence and production
Geranyl acetate is a constituent of many essential oils, including Ceylon citronella, palmarosa, lemon grass, petit grain, neroli, geranium, coriander, carrot, Camden woollybutt, and sassafras. It can be obtained by fractional distillation of the essential oils obtained from these sources, but more commonly it is prepared by the esterification of geraniol with acetic acid.
Uses
Geranyl acetate is used primarily as a component of perfumes for creams and soaps and as a flavoring ingredient. It is used particularly in rose, lavender and geranium formulations where a sweet fruity or citrus aroma is desired. It is designated by the U.S. Food and Drug Administration as generally recognized as safe (GRAS).
See also
Neryl acetate
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https://en.wikipedia.org/wiki/Visual%20modeling
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Visual modeling is the graphic representation of objects and systems of interest using graphical languages. Visual modeling is a way for experts and novices to have a common understanding of otherwise complicated ideas. By using visual models complex ideas are not held to human limitations, allowing for greater complexity without a loss of comprehension. Visual modeling can also be used to bring a group to a consensus. Models help effectively communicate ideas among designers, allowing for quicker discussion and an eventual consensus. Visual modeling languages may be General-Purpose Modeling (GPM) languages (e.g., UML, Southbeach Notation, IDEF) or Domain-Specific Modeling (DSM) languages (e.g., SysML). Visual modelling in computer science had no standard before the 90's, and was incomparable until the introduction of the UML. They include industry open standards (e.g., UML, SysML, Modelica), as well as proprietary standards, such as the visual languages associated with VisSim, MATLAB and Simulink, OPNET, NetSim, NI Multisim, and Reactive Blocks. Both VisSim and Reactive Blocks provide a royalty-free, downloadable viewer that lets anyone open and interactively simulate their models. The community edition of Reactive Blocks also allows full editing of the models as well as compilation, as long as the work is published under the Eclipse Public License. Visual modeling languages are an area of active research that continues to evolve, as evidenced by increasing interest in DSM languages, visual requirements, and visual OWL (Web Ontology Language).
See also
Service-oriented modeling
Domain-specific modeling
Model-driven engineering
Modeling language
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https://en.wikipedia.org/wiki/Mosaic%20virus
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A mosaic virus is any virus that causes infected plant foliage to have a mottled appearance. Such viruses come from a variety of unrelated lineages and consequently there is no taxon that unites all mosaic viruses.
Examples
Virus species that contained the word 'mosaic' in their English language common name are listed below, though with the nomenclature and taxonomy of the ICTV 2022 release. However, not all viruses that may cause a mottled appearance belong to species that include the word "mosaic" in the name.
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https://en.wikipedia.org/wiki/OMA%20Device%20Management
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OMA Device Management is a device management protocol specified by the Open Mobile Alliance (OMA) Device Management (DM) Working Group and the Data Synchronization (DS) Working Group. The current approved specification of OMA DM is version 1.2.1, the latest modifications to this version released in June 2008. The candidate release 2.0 was scheduled to be finalized in September 2013.
Overview
OMA DM specification is designed for management of mobile devices such as mobile phones, PDAs, and tablet computers. Device management is intended to support the following uses:
Provisioning – Configuration of the device (including first time use), enabling and disabling features
Device Configuration – Allow changes to settings and parameters of the device
Software Upgrades – Provide for new software and/or bug fixes to be loaded on the device, including applications and system software
Fault Management – Report errors from the device, query about status of device
All of the above functions are supported by the OMA DM specification, and a device may optionally implement all or a subset of these features. Since OMA DM specification is aimed at mobile devices, it is designed with sensitivity to the following:
small footprint devices, where memory and storage space may be limited
constraint on bandwidth of communication, such as in wireless connectivity
tight security, as the devices are vulnerable to software attacks; authentication and challenges are made part of the specifications
Technical description
OMA DM was originally developed by The SyncML Initiative Ltd, an industry consortium formed by many mobile device manufacturers. The SyncML Initiative got consolidated into the OMA umbrella as the scope and use of the specification was expanded to include many more devices and support global operation.
Technically, the OMA DM protocol uses XML for data exchange, more specifically the sub-set defined by SyncML. The device management takes place by communication betw
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https://en.wikipedia.org/wiki/Behrouz%20Nikbin
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Behrouz Nikbin (born in Iran) is an Iranian immunologist and biomedical scientist. Nikbin studied medicine at Tehran University and got a PhD degree in immunology.
External links
Behrouz Nikbin's publications in pubmed
Iranian immunologists
Living people
Year of birth missing (living people)
University of Tehran alumni
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https://en.wikipedia.org/wiki/Virial%20stress
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Virial stress is a measure of mechanical stress on an atomic scale for homogeneous systems.
The expression of the (local) virial stress can be derived as the functional derivative of the free energy of a molecular system with respect to the deformation tensor.
Volume averaged Definition
The instantaneous volume averaged virial stress is given by
where
and are atoms in the domain,
is the volume of the domain,
is the mass of atom k,
is the ith component of the velocity of atom k,
is the jth component of the average velocity of atoms in the volume,
is the ith component of the position of atom k, and
is the ith component of the force applied on atom by atom .
At zero kelvin, all velocities are zero so we have
.
This can be thought of as follows. The τ11 component of stress is the force in the x1-direction divided by the area of a plane perpendicular to that direction. Consider two adjacent volumes separated by such a plane. The 11-component of stress on that interface is the sum of all pairwise forces between atoms on the two sides.
The volume averaged virial stress is then the ensemble average of the instantaneous volume averaged virial stress.
In a three dimensional, isotropic system, at equilibrium the "instantaneous" atomic pressure is usually defined as the average over the diagonals of the negative stress tensor:
The pressure then is the ensemble average of the instantaneous pressure
This pressure is the average pressure in the volume .
Equivalent Definition
It's worth noting that some articles and textbook use a slightly different but equivalent version of the equation
where is the ith component of the vector oriented from the th atoms to the kth calculated via the difference
Both equation being strictly equivalent, the definition of the vector can still lead to confusion.
Derivation
The virial pressure can be derived, using the virial theorem and splitting forces between particles and the container or, alternatively, via direct
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https://en.wikipedia.org/wiki/Hydrostatic%20stress
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In continuum mechanics, hydrostatic stress, also known as volumetric stress, is a component of stress which contains uniaxial stresses, but not shear stresses. A specialized case of hydrostatic stress contains isotropic compressive stress, which changes only in volume, but not in shape. Pure hydrostatic stress can be experienced by a point in a fluid such as water. It is often used interchangeably with "pressure" and is also known as confining stress, particularly in the field of geomechanics.
Hydrostatic stress is equivalent to the average of the uniaxial stresses along three orthogonal axes and can be calculated from the first invariant of the stress tensor:
Its magnitude in a fluid, , can be given by:
where
is an index denoting each distinct layer of material above the point of interest;
is the density of each layer;
is the gravitational acceleration (assumed constant here; this can be substituted with any acceleration that is important in defining weight);
is the height (or thickness) of each given layer of material.
For example, the magnitude of the hydrostatic stress felt at a point under ten meters of fresh water would be
where the index indicates "water".
Because the hydrostatic stress is isotropic, it acts equally in all directions. In tensor form, the hydrostatic stress is equal to
where is the 3-by-3 identity matrix.
Hydrostatic compressive stress is used for the determination of the bulk modulus for materials.
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https://en.wikipedia.org/wiki/Neurotrophin-3
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Neurotrophin-3 is a protein that in humans is encoded by the NTF3 gene.
The protein encoded by this gene, NT-3, is a neurotrophic factor in the NGF (Nerve Growth Factor) family of neurotrophins. It is a protein growth factor which has activity on certain neurons of the peripheral and central nervous system; it helps to support the survival and differentiation of existing neurons, and encourages the growth and differentiation of new neurons and synapses. NT-3 was the third neurotrophic factor to be characterized, after nerve growth factor (NGF) and BDNF (Brain Derived Neurotrophic Factor).
Function
Although the vast majority of neurons in the mammalian brain are formed prenatally, parts of the adult brain retain the ability to grow new neurons from neural stem cells; a process known as neurogenesis. Neurotrophins are chemicals that help to stimulate and control neurogenesis.
NT-3 is unique in the number of neurons it can potentially stimulate, given its ability to activate two of the receptor tyrosine kinase neurotrophin receptors (TrkC and TrkB).
Mice born without the ability to make NT-3 have loss of proprioceptive and subsets of mechanoreceptive sensory neurons.
Mechanism of action
NT-3 binds three receptors on the surface of cells which are capable of responding to this growth factor:
TrkC (pronounced "Track C"), is apparently the "physiologic" receptor, in that it binds with greatest affinity to NT-3.
However, NT-3 is capable of binding and signaling through a TrkC-related receptors called TrkB.
Finally, NT-3 also binds a second-receptor type besides Trk receptors, called the LNGFR (for "low affinity nerve growth factor receptor).
High affinity receptors
TrkC is a receptor tyrosine kinase (meaning it mediates its actions by causing the addition of phosphate molecules on certain tyrosines in the cell, activating cellular signaling).
As mentioned above, there are other related Trk receptors, TrkA and TrkB. Also as mentioned, there are other neurotroph
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https://en.wikipedia.org/wiki/Simmons%27%20citrate%20agar
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Simmons' citrate agar is used for differentiating gram-negative bacteria on the basis of citrate utilization, especially for distinguishing Gammaproteobacteria of the family Enterobacteriaceae or even between species of the same genus. For example, Salmonella enteritidis would yield a positive (blue) result on Simmons’ agar and thus be distinguished from other Salmonella species like Salmonella typhi, Salmonella pullorum, and Salmonella gallinarum, which would yield a negative (green) result.
One common application for Simmons’ agar is to monitor food or water for fecal contamination, which is indicated by the presence of fecal coliforms in the Enterobacterales order such as E. coli. In a sample, E. coli, which is citrate-negative, can be distinguished from non-fecal, citrate-positive coliforms that are often found in water, soil, and on plants using Simmons’ agar. Additionally, Simmons’ agar is commonly used as part of the IMViC tests to identify coliforms.
It is useful for selecting for organisms that use citrate as its main carbon and energy source. It is a defined, selective and differential medium that tests for an organism's ability to use citrate as a sole carbon source and ammonium ions as the sole nitrogen source. After citrate enters a cell through citrate permeases, citrate lyase cleaves it into acetate and oxaloacetate, which is further broken down into carbon dioxide and pyruvate. Depending on the pH of the cell, pyruvate can turn into acetate and formate at pH below 7, or acetate + lactate + carbon dioxide and acetoin + carbon dioxide at pH 7 and below. When water and sodium carbonate in the agar reacts with carbon dioxide released in citrate metabolism, alkaline products form and raise the pH, leading to the agar changing color from green to blue.
The medium contains sodium chloride, sodium citrate, ammonium dihydrogen phosphate, dipotassium phosphate, and magnesium sulphate. It also contains bromothymol blue, a pH indicator. Bromothymol blue is g
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https://en.wikipedia.org/wiki/Wireshark
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Wireshark is a free and open-source packet analyzer. It is used for network troubleshooting, analysis, software and communications protocol development, and education. Originally named Ethereal, the project was renamed Wireshark in May 2006 due to trademark issues.
Wireshark is cross-platform, using the Qt widget toolkit in current releases to implement its user interface, and using pcap to capture packets; it runs on Linux, macOS, BSD, Solaris, some other Unix-like operating systems, and Microsoft Windows. There is also a terminal-based (non-GUI) version called TShark. Wireshark, and the other programs distributed with it such as TShark, are free software, released under the terms of the GNU General Public License version 2 or any later version.
Functionality
Wireshark is very similar to tcpdump, but has a graphical front-end and integrated sorting and filtering options.
Wireshark lets the user put network interface controllers into promiscuous mode (if supported by the network interface controller), so they can see all the traffic visible on that interface including unicast traffic not sent to that network interface controller's MAC address. However, when capturing with a packet analyzer in promiscuous mode on a port on a network switch, not all traffic through the switch is necessarily sent to the port where the capture is done, so capturing in promiscuous mode is not necessarily sufficient to see all network traffic. Port mirroring or various network taps extend capture to any point on the network. Simple passive taps are extremely resistant to tampering.
On Linux, BSD, and macOS, with libpcap 1.0.0 or later, Wireshark 1.4 and later can also put wireless network interface controllers into monitor mode.
If a remote machine captures packets and sends the captured packets to a machine running Wireshark using the TZSP protocol or the protocol used by OmniPeek, Wireshark dissects those packets, so it can analyze packets captured on a remote machine at the time
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https://en.wikipedia.org/wiki/Chordin
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Chordin (from Greek χορδή, string, catgut) is a protein with a prominent role in dorsal–ventral patterning during early embryonic development. In humans it is encoded for by the CHRD gene.
History
Chordin was originally identified in the African clawed frog (Xenopus laevis) in the laboratory of Edward M. De Robertis as a key developmental protein that dorsalizes early vertebrate embryonic tissues. It was first hypothesized that chordin plays a role in the dorsal homeobox genes in Spemann's organizer. The chordin gene was discovered through its activation following use of gsc (goosecoid) and Xnot mRNA injections. The discoverers of chordin concluded that it is expressed in embryo regions where gsc and Xnot were also expressed, which included the prechordal plate, the notochord, and the chordoneural hinge. The expression of the gene in these regions led to the name chordin. Initial functions of chordin were thought to include recruitment of neighboring cells to assist in the forming of the axis along with mediating cell interactions for organization of tail, head, and body regions.
Protein Structure
Chordin is a 941 amino-acids long protein, whose three-dimensional transmission electron microscopy structure resembles a horseshoe. A characteristic structural feature of chordin is the presence of four cysteine-rich repeats, which are 58–75 residues long, each containing 10 cysteines with characteristic spacings. These repeats are homologous with domains in a number of extracellular matrix proteins, including von Willebrand factor. There are five named isoforms of this protein that are produced by alternative splicing.
Gene structure
CHRD is 23 exons long and has a length of 11.5 kb and is localized at 3q27. The THPO (thrombopoietin) gene is located in the same single cosmid clone along with the eukaryotic translation initiation factor-4-gamma gene (EIF4G1).
Function
Chordin dorsalizes the developing embryo by binding ventralizing TGFβ proteins such as bone morph
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https://en.wikipedia.org/wiki/Srulik
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Srulik (, ) is a cartoon character symbolizing Israel. The character was created in 1956 by the Israeli cartoonist Kariel Gardosh, known by his pen name Dosh.
The cartoon appeared for many years in the newspaper Maariv. Yosef Lapid, Dosh's colleague on the editorial board of Maariv, described Srulik as an icon of Israel in the same way that Marianne and Columbia were respectively icons of France and the United States. Srulik has been a common nickname in Israel for boys named "Yisrael" ("Israel", from ), although by the 2000's it has become an outdated nickname.
Description
Srulik is generally depicted as a young man wearing a tembel hat, Biblical sandals, and khaki shorts. Srulik is a pioneering Zionist, a lover of the land of Israel and its soil, a dedicated farmer who in time of need puts on a uniform and goes out to defend the state of Israel. Dosh drew Srulik in cartoons on current events for Maariv, and also for various "specials" and occasions of the young state. During wartime, Srulik put on a uniform and was drafted to raise the national morale.
Symbolism
Many have pointed out Srulik's function as an antithesis of the antisemitic caricatures which appeared in Der Stürmer and other European and Arab journals. As against the stereotype of the weak or cunning Jew that was propagated by Joseph Goebbels, Dosh — a Holocaust survivor — drew a proud, strong and sympathetic Jewish character. The journalist Shalom Rosenfeld, editor of Maariv in 1974–1980, wrote:
Handala
Srulik has been compared to Handala, the Palestinian national personification, and has appeared together with Handala in murals supporting the two-state solution.
See also
Sabra (person)
Culture of Israel
Negation of the Diaspora
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https://en.wikipedia.org/wiki/Chronocentrism
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Chronocentrism is the assumption that certain time periods (typically the present) are better, more important, or a more significant frame of reference than other time periods, either past or future. The perception of more positive attributes such as morality, technology, and sophistication to one's own time could lead an individual as a member of a collectivity to impose their forms of time on others and impede the efforts towards more homogeneous temporal commons.
History
Chronocentrism (from the Greek chrono- meaning "time") was coined by sociologist Jib Fowles in an article in the journal Futures in February, 1974. Fowles described chronocentrism as "the belief that one's own times are paramount, that other periods pale in comparison". A critical view described it as the belief that only the present counts and that the past is irrelevant except to serve as a reference to a few basic assumptions about what went before. More recently, it has been defined as "the egotism that one's own generation is poised on the very cusp of history". The term had been used earlier in a study about attitudes to ageing in the workplace. Chronocentricity: "...only seeing the value of one's own age cohort...described the tendency for younger managers to hold negative perceptions of the abilities or other work-related competencies of older employees." This type of discrimination is a form of ageism.
Ethnocentrism
Chronocentrism as ethnocentrism is the perceiving and judging of a culture's historical values in terms of the standards of one's own time period.
Antichronocentrism
The Long Now Foundation is an organization that encourages the use of 5-digit years, e.g. "02016" instead of "2016," to help emphasize how early the present time is in their vision of the timeline of humanity. The use of two-digit years before Y2K was an example of chronocentrism (in the early years of computing, the years 2000 and 1899 were believed to be too far in the future or the past, and thus of less
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https://en.wikipedia.org/wiki/Triangle%20mesh
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In computer graphics, a triangle mesh is a type of polygon mesh. It comprises a set of triangles (typically in three dimensions) that are connected by their common edges or vertices.
Many graphics software packages and hardware devices can operate more efficiently on triangles that are grouped into meshes than on a similar number of triangles that are presented individually. This is typically because computer graphics do operations on the vertices at the corners of triangles. With individual triangles, the system has to operate on three vertices for every triangle. In a large mesh, there could be eight or more triangles meeting at a single vertex - by processing those vertices just once, it is possible to do a fraction of the work and achieve an identical effect.
In many computer graphics applications it is necessary to manage a mesh of triangles. The mesh components are vertices, edges, and triangles. An application might require knowledge of the various connections between the mesh components. These connections can be managed independently of the actual vertex positions. This document describes a simple data structure that is convenient for managing the connections. This is not the only possible data structure. Many other types exist and have support for various queries about meshes.
Representation
Various methods of storing and working with a mesh in computer memory are possible. With the OpenGL and DirectX APIs there are two primary ways of passing a triangle mesh to the graphics hardware, triangle strips and index arrays.
Triangle strip
One way of sharing vertex data between triangles is the triangle strip. With strips of triangles each triangle shares one complete edge with one neighbour and another with the next. Another way is the triangle fan which is a set of connected triangles sharing one central vertex. With these methods vertices are dealt with efficiently resulting in the need to only process N+2 vertices in order to draw N triangles.
Tria
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https://en.wikipedia.org/wiki/Stochastic%20volatility
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In statistics, stochastic volatility models are those in which the variance of a stochastic process is itself randomly distributed. They are used in the field of mathematical finance to evaluate derivative securities, such as options. The name derives from the models' treatment of the underlying security's volatility as a random process, governed by state variables such as the price level of the underlying security, the tendency of volatility to revert to some long-run mean value, and the variance of the volatility process itself, among others.
Stochastic volatility models are one approach to resolve a shortcoming of the Black–Scholes model. In particular, models based on Black-Scholes assume that the underlying volatility is constant over the life of the derivative, and unaffected by the changes in the price level of the underlying security. However, these models cannot explain long-observed features of the implied volatility surface such as volatility smile and skew, which indicate that implied volatility does tend to vary with respect to strike price and expiry. By assuming that the volatility of the underlying price is a stochastic process rather than a constant, it becomes possible to model derivatives more accurately.
A middle ground between the bare Black-Scholes model and stochastic volatility models is covered by local volatility models. In these models the underlying volatility does not feature any new randomness but it isn't a constant either. In local volatility models the volatility is a non-trivial function of the underlying asset, without any extra randomness. According to this definition, models like constant elasticity of variance would be local volatility models, although they are sometimes classified as stochastic volatility models. The classification can be a little ambiguous in some cases.
The early history of stochastic volatility has multiple roots (i.e. stochastic process, option pricing and econometrics), it is reviewed in Chapter 1 o
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https://en.wikipedia.org/wiki/Relationship%20between%20string%20theory%20and%20quantum%20field%20theory
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Many first principles in quantum field theory are explained, or get further insight, in string theory.
From quantum field theory to string theory
Emission and absorption: one of the most basic building blocks of quantum field theory, is the notion that particles (such as electrons) can emit and absorb other particles (such as photons). Thus, an electron may just "split" into an electron plus a photon, with a certain probability (which is roughly the coupling constant). This is described in string theory as one string splitting into two. This process is an integral part of the theory. The mode on the original string also "splits" between its two parts, resulting in two strings which possibly have different modes, representing two different particles.
Coupling constant: in quantum field theory this is, roughly, the probability for one particle to emit or absorb another particle, the latter typically being a gauge boson (a particle carrying a force). In string theory, the coupling constant is no longer a constant, but is rather determined by the abundance of strings in a particular mode, the dilaton. Strings in this mode couple to the worldsheet curvature of other strings, so their abundance through space-time determines the measure by which an average string worldsheet will be curved. This determines its probability to split or connect to other strings: the more a worldsheet is curved, the higher a chance of splitting and reconnecting it has.
Spin: each particle in quantum field theory has a particular spin s, which is an internal angular momentum. Classically, the particle rotates in a fixed frequency, but this cannot be understood if particles are point-like. In string theory, spin is understood by the rotation of the string; For example, a photon with well-defined spin components (i.e. in circular polarization) looks like a tiny straight line revolving around its center.
Gauge symmetry: in quantum field theory, the mathematical description of physical fields i
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https://en.wikipedia.org/wiki/%CE%92-Hydroxybutyric%20acid
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β-Hydroxybutyric acid, also known as 3-hydroxybutyric acid or BHB, is an organic compound and a beta hydroxy acid with the chemical formula CH3CH(OH)CH2CO2H; its conjugate base is β-hydroxybutyrate, also known as 3-hydroxybutyrate. β-Hydroxybutyric acid is a chiral compound with two enantiomers: D-β-hydroxybutyric acid and L-β-hydroxybutyric acid. Its oxidized and polymeric derivatives occur widely in nature. In humans, D-β-hydroxybutyric acid is one of two primary endogenous agonists of hydroxycarboxylic acid receptor 2 (HCA2), a G protein-coupled receptor (GPCR).
Biosynthesis
In humans, can be synthesized in the liver via the metabolism of fatty acids (e.g., butyrate), , and ketogenic amino acids through a series of reactions that metabolize these compounds into acetoacetate, which is the first ketone body that is produced in the fasting state. The biosynthesis of from acetoacetate is catalyzed by the β-hydroxybutyrate dehydrogenase enzyme.
Butyrate can also be metabolized into via a second metabolic pathway that does not involve acetoacetate as a metabolic intermediate. This metabolic pathway is as follows:
butyrate→butyryl-CoA→crotonyl-CoA→β-hydroxybutyryl-CoA→poly-β-hydroxybutyrate→()→
The last reaction in this metabolic pathway, which involves the conversion of () into , is catalyzed by the hydroxybutyrate-dimer hydrolase enzyme.
The concentration of β-hydroxybutyrate in human blood plasma, as with other ketone bodies, increases through ketosis. This elevated β-hydroxybutyrate level is naturally expected, as β-hydroxybutyrate is formed from acetoacetate. The compound can be used as an energy source by the brain and skeletal muscle when blood glucose is low. Diabetic patients can have their ketone levels tested via urine or blood to indicate diabetic ketoacidosis. In alcoholic ketoacidosis, this ketone body is produced in greatest concentration. Ketogenesis occurs if oxaloacetate in the liver cells is depleted, a circumstance created by reduced carbo
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https://en.wikipedia.org/wiki/Red%20Data%20Book%20of%20the%20Russian%20Federation
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Red Data Book of the Russian Federation (RDBRF), also known as Red Book () or Russian Red Data Book, is a state document established for documenting rare and endangered species of animals, plants and fungi, as well as some local subspecies (such as the Ladoga seal) that exist within the territory of the Russian Federation and its continental shelf and marine economic zone. The book has been adopted by Russia to enact a common agreement on rare and endangered species protection.
Conservation
The book provides a central information source in organizing studies and monitoring programs on rare and endangered species and their habitats.
History
The first Russian Red Data Book was based upon research conducted between 1961 and 1964 by a number of Soviet biologists. It represented the Soviet part of the IUCN Red List (hence the name). At that time it was just the Soviet Union's first organized list of endangered species, not a legislative document.
In the late 1960s, more research was conducted. In 1974, the Ministry of Agriculture (Russia) adopted the first official Red Book, which was published in 1978. In 1984, the second revision was published as Red Data Book of the Russian Soviet Federative Socialist Republic (RSFSR), exclusively for animals.
The document complemented law as a list of endangered species. Animals on the list were strictly protected and their treatment regulated by Soviet law.
In 1988, the Red Data Book of the RSFSR for plants was published with 533 species of plants including 465 species of vascular plants, 22 species of bryophytes, 29 species of lichens and 17 species of fungi.
After the collapse of the Soviet Union, regulations on endangered species were instituted by each of the former Soviet countries. As of 2003, the absence of a federal regulation rendered regional Red Listing "chaotic and uncontrolled" with 37 regional Red Data Books covering 42 out of 89 Russian regions. Most of these Red Data Books did not meet federal requirements
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https://en.wikipedia.org/wiki/Cat%20communication
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Cats need to communicate with each other for bonding, and relating with each other; they need to collaborate, play, and share resources. When they communicate with humans, they do so to get what they need or want, such as food, affection, or play.
Cats use a range of communication methods such as vocal, visual, tactile and olfactory. Cats mostly meow to communicate with humans, rarely with other animals. As such, the cats' communication methods have been significantly affected by domestication. Up to 21 different cat vocalizations have been studied. It is now evident that domestic cats meow more than feral cats.
Vocal
Cat vocalizations have been categorized according to a range of characteristics. Originally suggested by Mildred Moelk, cat sounds are often divided into three main classes:
sounds produced with the mouth closed (murmurs – purring, trilling)
sounds produced when the mouth is first opened and then gradually closed (meowing, howling, yowling)
sounds produced with the mouth held tensely open in the same position (growls, snarls, hisses, spits, chattering, and chirping).
In 1944, Moelk published the first phonetic study of cat sounds. She listened very carefully to her own cats and organized their sounds into 16 phonetic patterns divided into three main categories. She also used a phonetic alphabet to transcribe or write down the different sounds. She claimed that cats had six different forms of meows to represent friendliness, confidence, dissatisfaction, anger, fear and pain. Moelk classified eight other sounds involved in mating and fighting by listening to the animals in her yard and on the street.
Brown et al. categorized vocal responses of cats according to the behavioral context: during separation of kittens from mother cats, during food deprivation, during pain, prior to or during threat or attack behavior, as in disputes over territory or food, during a painful or acutely stressful experience, as in routine prophylactic injections and d
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https://en.wikipedia.org/wiki/Coliphage
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A coliphage is a type of bacteriophage that infects coliform bacteria such as Escherichia coli. Coliphage originate almost exclusively from human feces and from other warm-blooded animals. When certain circumstances are met, such as a large number of susceptible hosts present at the right temperature, they can only partially replicate in sewage and contaminated waters.
Examples include Enterobacteria phage λ and species from the family Fersviridae. Coliphage levels reflect the persistence of pathogenic viruses in the environment and have been proposed as an indicator of fecal contamination in water.
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https://en.wikipedia.org/wiki/Biohydrogen
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Biohydrogen is H2 that is produced biologically. Interest is high in this technology because H2 is a clean fuel and can be readily produced from certain kinds of biomass, including biological waste. Furthermore some photosynthetic microorganisms are capable to produce H2 directly from water splitting using light as energy source.
Besides the promising possibilities of biological hydrogen production, many challenges characterize this technology. First challenges include those intrinsic to H2, such as storage and transportation of an explosive noncondensible gas. Additionally, hydrogen producing organisms are poisoned by O2 and yields of H2 are often low.
Biochemical principles
The main reactions driving hydrogen formation involve the oxidation of substrates to obtain electrons. Then, these electrons are transferred to free protons to form molecular hydrogen. This proton reduction reaction is normally performed by an enzyme family known as hydrogenases.
In heterotrophic organisms, electrons are produced during the fermentation of sugars.Hydrogen gas is produced in many types of fermentation as a way to regenerate NAD+ from NADH. Electrons are transferred to ferredoxin, or can be directly accepted from NADH by a hydrogenase, producing H2. Because of this most of the reactions start with glucose, which is converted to acetic acid.
C6H12O6 + 2 H2O -> 2 CH3COOH + 2 CO2 + 4 H2
A related reaction gives formate instead of carbon dioxide:
C6H12O6 + 2 H2O -> 2 CH3COOH + 2 HCOOH + 2 H2
These reactions are exergonic by 216 and 209 kcal/mol, respectively.
It has been estimated that 99% of all organisms utilize or produce dihydrogen (H2). Most of these species are microbes and their ability to use or produce H2 as a metabolite arises from the expression of H2 metalloenzymes known as hydrogenases. Enzymes within this widely diverse family are commonly sub-classified into three different types based on the active site metal content: [FeFe]-hydrogenases (iron-iron),
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https://en.wikipedia.org/wiki/NetPC
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NetPC is a standard for diskless PCs, developed by Microsoft and Intel as a competing standard to the Network Computer standard, because many NCs did not use Intel CPUs or Microsoft software. Network Computer was launched by Oracle Corporation in the mid-1990s.
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https://en.wikipedia.org/wiki/Max%20Planck%20Institute%20for%20Solar%20System%20Research
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The Max Planck Institute for Solar System Research (abbreviation: MPS; ) is a research institute in astronomy and astrophysics located in Göttingen, Germany, where it relocated in February 2014 from the nearby village of Lindau. The exploration of the Solar System is the central theme for research done at this institute.
MPS is a part of the Max Planck Society, which operates 80 research facilities in Germany.
Research
MPS is organised in three departments: Sun and Heliosphere, Planets and Comets, and Solar and Stellar Interiors. In addition, since 2002 there is also an International Max Planck Research School.
Subjects of research at the institute are the various objects within the Solar System. A major area of study concerns the Sun, its atmosphere, the interplanetary medium as influenced by the solar wind, as well as the impact of solar particles and radiation on the planets. The second area of research involves the interiors, surfaces, atmospheres, ionospheres, and magnetospheres of the planets and their moons, as well as of comets and asteroids.
A further essential part of the activities at the institute is the development and construction of instruments for space missions.
The analysis and interpretation of the acquired datasets are accompanied by intensive theoretical work. Physical models are proposed and then tested and further developed with the aid of computer simulations.
The Sun and heliosphere
The researchers at the MPS are studying the complete range of dynamic and often spectacular processes occurring on the Sun – from the interior to the outer heliosphere. At the heart of this research is the magnetic field, which plays a decisive role in these processes. It is generated by gas currents in the interior of the Sun and causes, among other things, dark spots on the surface. Answers to the following questions are being sought: Why does the magnetic field change with an eleven-year cycle? How does the magnetic field produce the various structures
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https://en.wikipedia.org/wiki/Partial%20geometry
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An incidence structure consists of points , lines , and flags where a point is said to be incident with a line if . It is a (finite) partial geometry if there are integers such that:
For any pair of distinct points and , there is at most one line incident with both of them.
Each line is incident with points.
Each point is incident with lines.
If a point and a line are not incident, there are exactly pairs , such that is incident with and is incident with .
A partial geometry with these parameters is denoted by .
Properties
The number of points is given by and the number of lines by .
The point graph (also known as the collinearity graph) of a is a strongly regular graph: .
Partial geometries are dual structures: the dual of a is simply a .
Special case
The generalized quadrangles are exactly those partial geometries with .
The Steiner systems are precisely those partial geometries with .
Generalisations
A partial linear space of order is called a semipartial geometry if there are integers such that:
If a point and a line are not incident, there are either or exactly pairs , such that is incident with and is incident with .
Every pair of non-collinear points have exactly common neighbours.
A semipartial geometry is a partial geometry if and only if .
It can be easily shown that the collinearity graph of such a geometry is strongly regular with parameters
.
A nice example of such a geometry is obtained by taking the affine points of and only those lines that intersect the plane at infinity in a point of a fixed Baer subplane; it has parameters .
See also
Strongly regular graph
Maximal arc
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https://en.wikipedia.org/wiki/Epigraph%20%28mathematics%29
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In mathematics, the epigraph or supergraph of a function valued in the extended real numbers is the set, denoted by of all points in the Cartesian product lying on or above its graph. The strict epigraph is the set of points in lying strictly above its graph.
Importantly, although both the graph and epigraph of consists of points in the epigraph consists of points in the subset which is not necessarily true of the graph of
If the function takes as a value then will be a subset of its epigraph
For example, if then the point will belong to but not to
These two sets are nevertheless closely related because the graph can always be reconstructed from the epigraph, and vice versa.
The study of continuous real-valued functions in real analysis has traditionally been closely associated with the study of their graphs, which are sets that provide geometric information (and intuition) about these functions. Epigraphs serve this same purpose in the fields of convex analysis and variational analysis, in which the primary focus is on convex functions valued in instead of continuous functions valued in a vector space (such as or ). This is because in general, for such functions, geometric intuition is more readily obtained from a function's epigraph than from its graph. Similarly to how graphs are used in real analysis, the epigraph can often be used to give geometrical interpretations of a convex function's properties, to help formulate or prove hypotheses, or to aid in constructing counterexamples.
Definition
The definition of the epigraph was inspired by that of the graph of a function, where the of is defined to be the set
The or of a function valued in the extended real numbers is the set
In the union over that appears above on the right hand side of the last line, the set may be interpreted as being a "vertical ray" consisting of and all points in "directly above" it.
Similarly, the set of points on or below the graph of a functio
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https://en.wikipedia.org/wiki/Enterprise%20data%20modelling
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Enterprise data modelling or enterprise data modeling (EDM) is the practice of creating a graphical model of the data used by an enterprise or company. Typical outputs of this activity include an enterprise data model consisting of entity–relationship diagrams (ERDs), XML schemas (XSD), and an enterprise wide data dictionary.
Overview
Producing such a model allows for a business to get a 'helicopter' view of their enterprise. In EAI (enterprise application integration) an EDM allows data to be represented in a single idiom, enabling the use of a common syntax for the XML of services or operations and the physical data model for database schema creation. Data modeling tools for ERDs that also allow the user to create a data dictionary are usually used to aid in the development of an EDM.
The implementation of an EDM is closely related to the issues of data governance and data stewardship within an organization.
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https://en.wikipedia.org/wiki/Friction%20of%20distance
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Friction of distance is a core principle of geography that states that movement incurs some form of cost, in the form of physical effort, energy, time, and/or the expenditure of other resources, and that these costs are proportional to the distance traveled. This cost is thus a resistance against movement, analogous (but not directly related) to the effect of friction against movement in classical mechanics. The subsequent preference for minimizing distance and its cost underlies a vast array of geographic patterns from economic agglomeration to wildlife migration, as well as many of the theories and techniques of spatial analysis, such as Tobler's first law of geography, network routing, and cost distance analysis. To a large degree, friction of distance is the primary reason why geography is relevant to many aspects of the world, although its importance (and perhaps the importance of geography) has been decreasing with the development of transportation and communication technologies.
History
It is not known who first coined the term "friction of distance," but the effect of distance-based costs on geographic activity and geographic patterns has been a core element of academic geography since its initial rise in the 19th Century. von Thünen's isolated state model of exurban land use (1826), possibly the earliest geographic theory, directly incorporated the cost of transportation of different agricultural products as one of the determinants for how far from a town each type of goods could be produced profitably. The industrial location theory of Alfred Weber (1909) and the central place theory of Walter Christaller (1933) were also basically optimizations of space to minimize travel costs.
By the 1920s, social scientists began to incorporate principles of physics (more precisely, some of its mathematical formalizations), such as gravity, specifically the inverse square law found in Newton's law of universal gravitation. Geographers quickly identified a number of
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https://en.wikipedia.org/wiki/Arc%20%28projective%20geometry%29
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An (simple) arc in finite projective geometry is a set of points which satisfies, in an intuitive way, a feature of curved figures in continuous geometries. Loosely speaking, they are sets of points that are far from "line-like" in a plane or far from "plane-like" in a three-dimensional space. In this finite setting it is typical to include the number of points in the set in the name, so these simple arcs are called -arcs. An important generalization of the -arc concept, also referred to as arcs in the literature, are the ()-arcs.
-arcs in a projective plane
In a finite projective plane (not necessarily Desarguesian) a set of points such that no three points of are collinear (on a line) is called a {{math|k - arc}}. If the plane has order then , however the maximum value of can only be achieved if is even. In a plane of order , a -arc is called an oval and, if is even, a -arc is called a hyperoval.
Every conic in the Desarguesian projective plane PG(2,), i.e., the set of zeros of an irreducible homogeneous quadratic equation, is an oval. A celebrated result of Beniamino Segre states that when is odd, every -arc in PG(2,) is a conic (Segre's theorem). This is one of the pioneering results in finite geometry.
If is even and is a -arc in , then it can be shown via combinatorial arguments that there must exist a unique point in (called the nucleus of ) such that the union of and this point is a ( + 2)-arc. Thus, every oval can be uniquely extended to a hyperoval in a finite projective plane of even order.
A -arc which can not be extended to a larger arc is called a complete arc. In the Desarguesian projective planes, PG(2,), no -arc is complete, so they may all be extended to ovals.
-arcs in a projective space
In the finite projective space PG() with , a set of points such that no points lie in a common hyperplane is called a (spatial) -arc. This definition generalizes the definition of a -arc in a plane (where ).
()-arcs in a projective plane
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https://en.wikipedia.org/wiki/TGF%20beta%201
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Transforming growth factor beta 1 or TGF-β1 is a polypeptide member of the transforming growth factor beta superfamily of cytokines. It is a secreted protein that performs many cellular functions, including the control of cell growth, cell proliferation, cell differentiation, and apoptosis. In humans, TGF-β1 is encoded by the gene.
Function
TGF-β is a multifunctional set of peptides that controls proliferation, differentiation, and other functions in many cell types. TGF-β acts synergistically with transforming growth factor-alpha (TGF-α) in inducing transformation. It also acts as a negative autocrine growth factor. Dysregulation of TGF-β activation and signaling may result in apoptosis. Many cells synthesize TGF-β and almost all of them have specific receptors for this peptide. TGF-β1, TGF-β2, and TGF-β3 all function through the same receptor signaling systems.
TGF-β1 was first identified in human platelets as a protein with a molecular mass of 25 kilodaltons with a potential role in wound healing. It was later characterized as a large protein precursor (containing 390 amino acids) that was proteolytically processed to produce a mature peptide of 112 amino acids.
TGF-β1 plays an important role in controlling the immune system, and shows different activities on different types of cell, or cells at different developmental stages. Most immune cells (or leukocytes) secrete TGF-β1.
T cells
Some T cells (e.g. regulatory T cells) release TGF-β1 to inhibit the actions of other T cells. Specifically, TGF-β1 prevents the interleukin(IL)-1- & interleukin-2-dependent proliferation in activated T cells, as well as the activation of quiescent helper T cells and cytotoxic T cells. Similarly, TGF-β1 can inhibit the secretion and activity of many other cytokines including interferon-γ, tumor necrosis factor-alpha (TNF-α), and various interleukins. It can also decrease the expression levels of cytokine receptors, such as the IL-2 receptor to down-regulate the activity of
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https://en.wikipedia.org/wiki/Evolutionary%20pressure
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Any cause that reduces or increases reproductive success in a portion of a population potentially exerts evolutionary pressure, selective pressure or selection pressure, driving natural selection. It is a quantitative description of the amount of change occurring in processes investigated by evolutionary biology, but the formal concept is often extended to other areas of research.
In population genetics, selective pressure is usually expressed as a selection coefficient.
Amino acids selective pressure
It has been shown that putting an amino acid bio-synthesizing gene like HIS4 gene under amino acid selective pressure in yeast causes enhancement of expression of adjacent genes which is due to the transcriptional co-regulation of two adjacent genes in Eukaryota.
Antibiotic resistance
Drug resistance in bacteria is an example of an outcome of natural selection.
When a drug is used on a species of bacteria, those that cannot resist die and do not produce offspring, while those that survive potentially pass on the resistance gene to the next generation (vertical gene transmission). The resistance gene can also be passed on to one bacterium by another of a different species (horizontal gene transmission). Because of this, the drug resistance increases over generations. For example, in hospitals, environments are created where pathogens such as C. difficile have developed a resistance to antibiotics.<ref name="Dawson">{{cite journal | author = Dawson L.F., Valiente E., Wren B.W. | year = 2009 | title = Clostridium difficile—A continually evolving and problematic pathogen. Infections | journal = Genetics and Evolution | volume = 9 | issue = 6| pages = 1410–1417 | doi=10.1016/j.meegid.2009.06.005| pmid = 19539054 }}</ref> Antibiotic resistance is made worse by the misuse of antibiotics. Antibiotic resistance is encouraged when antibiotics are used to treat non-bacterial diseases, and when antibiotics are not used for the prescribed amount of time or in the prescribed do
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https://en.wikipedia.org/wiki/Conway%20puzzle
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Conway's puzzle, or blocks-in-a-box, is a packing problem using rectangular blocks, named after its inventor, mathematician John Conway. It calls for packing thirteen 1 × 2 × 4 blocks, one 2 × 2 × 2 block, one 1 × 2 × 2 block, and three 1 × 1 × 3 blocks into a 5 × 5 × 5 box.
Solution
The solution of the Conway puzzle is straightforward once one realizes, based on parity considerations, that the three 1 × 1 × 3 blocks need to be placed so that precisely one of them appears in each 5 × 5 × 1 slice of the cube. This is analogous to similar insight that facilitates the solution of the simpler Slothouber–Graatsma puzzle.
See also
Soma cube
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https://en.wikipedia.org/wiki/Slothouber%E2%80%93Graatsma%20puzzle
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The Slothouber–Graatsma puzzle is a packing problem that calls for packing six 1 × 2 × 2 blocks and three 1 × 1 × 1 blocks into a 3 × 3 × 3 box. The solution to this puzzle is unique (up to mirror reflections and rotations). It was named after its inventors Jan Slothouber and William Graatsma.
The puzzle is essentially the same if the three 1 × 1 × 1 blocks are left out, so that the task is to pack six 1 × 2 × 2 blocks into a cubic box with volume 27.
Solution
The solution of the Slothouber–Graatsma puzzle is straightforward when one realizes that the three 1 × 1 × 1 blocks (or the three holes) need to be placed along a body diagonal of the box, as each of the 3 x 3 layers in the various directions needs to contain such a unit block. This follows from parity considerations, because the larger blocks can only fill an even number of the 9 cells in each 3 x 3 layer.
Variations
The Slothouber–Graatsma puzzle is an example of a cube-packing puzzle using convex polycubes. More general puzzles involving the packing of convex rectangular blocks exist. The best known example is the Conway puzzle which asks for the packing of eighteen convex rectangular blocks into a 5 x 5 x 5 box. A harder convex rectangular block packing problem is to pack forty-one 1 x 2 x 4 blocks into a 7 x 7 x 7 box (thereby leaving 15 holes); the solution is analogous to the 5x5x5 case, and has three 1x1x5 cuboidal holes in mutually perpendicular directions covering all 7 slices.
See also
Soma cube
Bedlam cube
Diabolical cube
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https://en.wikipedia.org/wiki/Phyllosphere
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In microbiology, the phyllosphere is the total above-ground surface of a plant when viewed as a habitat for microorganisms. The phyllosphere can be further subdivided into the caulosphere (stems), phylloplane (leaves), anthosphere (flowers), and carposphere (fruits). The below-ground microbial habitats (i.e. the thin-volume of soil surrounding root or subterranean stem surfaces) are referred to as the rhizosphere and laimosphere.
Most plants host diverse communities of microorganisms including bacteria, fungi, archaea, and protists . Some are beneficial to the plant, others function as plant pathogens and may damage the host plant or even kill it.
The phyllosphere microbiome
The leaf surface, or phyllosphere, harbours a microbiome comprising diverse communities of bacteria, archaea, fungi, algae and viruses. Microbial colonizers are subjected to diurnal and seasonal fluctuations of heat, moisture, and radiation. In addition, these environmental elements affect plant physiology (such as photosynthesis, respiration, water uptake etc.) and indirectly influence microbiome composition. Rain and wind also cause temporal variation to the phyllosphere microbiome.
The phyllosphere includes the total aerial (above-ground) surface of a plant, and as such includes the surface of the stem, flowers and fruit, but most particularly the leaf surfaces. Compared with the rhizosphere and the endosphere the phyllosphere is nutrient poor and its environment more dynamic.
Interactions between plants and their associated microorganisms in many of these microbiomes can play pivotal roles in host plant health, function, and evolution. Interactions between the host plant and phyllosphere bacteria have the potential to drive various aspects of host plant physiology. However, as of 2020 knowledge of these bacterial associations in the phyllosphere remains relatively modest, and there is a need to advance fundamental knowledge of phyllosphere microbiome dynamics.
The assembly of the phyl
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https://en.wikipedia.org/wiki/Follicle-stimulating%20hormone%20receptor
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The follicle-stimulating hormone receptor or FSH receptor (FSHR) is a transmembrane receptor that interacts with the follicle-stimulating hormone (FSH) and represents a G protein-coupled receptor (GPCR). Its activation is necessary for the hormonal functioning of FSH. FSHRs are found in the ovary, testis, and uterus.
FSHR gene
The gene for the FSHR is found on chromosome 2 p21 in humans. The gene sequence of the FSHR consists of about 2,080 nucleotides.
Receptor structure
The FSHR consists of 695 amino acids and has a molecular mass of about 76 kDa. Like other GPCRs, the FSH-receptor possesses seven membrane-spanning domains or transmembrane helices.
The extracellular domain of the receptor contains 11 leucine-rich repeats and is glycosylated. It has two subdomains, a hormone-binding subdomain followed by a signal-specificity subdomain. The hormone-binding subdomain is responsible for the high-affinity hormone binding, and the signal-specificity subdomain, containing a sulfated tyrosine at position 335 (sTyr) in a hinge loop, is required for the hormone activity.
The transmembrane domain contains two highly conserved cysteine residues that build disulfide bonds to stabilize the receptor structure. A highly conserved Asp-Arg-Tyr triplet motif is present in GPCR family members in general and may be of importance to transmit the signal. In FSHR and its closely related other glycoprotein hormone receptor members (LHR and TSHR), this conserved triplet motif is a variation Glu-Arg-Trp sequence.
The C-terminal domain is intracellular and brief, rich in serine and threonine residues for possible phosphorylation.
Ligand binding and signal transduction
Upon initial binding to the LRR region of FSHR, FSH reshapes its conformation to form a new pocket. FSHR then inserts its sulfotyrosine from the hinge loop into the pockets and activates the 7-helical transmembrane domain. This event leads to a transduction of the signal that activates the G protein that is bo
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https://en.wikipedia.org/wiki/HealthBoards
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HealthBoards is a long-running social networking support group website. It consists of over 280 Internet message boards for patient to patient health support (also referred to as a virtual community or an online health community). HealthBoards was one of the first stand alone health community websites. Health communities prior to it had generally been part of large web portals (WebMD, Yahoo, iVillage, etc.). The HealthBoards members post messages to share information and support on a wide range of health issues such as cancer, back pain, autism, and women's health. As of October 2013, the site had over 1 million registered members, 5 million posted messages, and over 10 million monthly visitors.
History
HealthBoards was founded in 1998 by Charles Simmons, a software engineer in Los Angeles, California. In 1997, after experiencing a variety of symptoms for which doctors had no explanation, Simmons turned to the Web for answers and support. When he did not find online support groups in the areas he needed, he realized that there was a need for a health support website covering a wide range of health topics. After a year of development, HealthBoards was launched on July 26, 1998, with 70 message boards. The original site was developed using custom Perl software written by Simmons. HealthBoards quickly gained popularity. In January 2001, the site began using an internet forum software package called UBB. By November 2003, HealthBoards had reached 100,000 members. Due to considerable growth in traffic and problems with UBB, the site was transitioned to VBulletin 3.0, a more robust internet forum software system. After 2003 HealthBoards experienced its most rapid growth and became one of the largest health communities on the Web. In 2005 HealthBoards was rated as one of the top 20 health websites by Consumer Reports Health WebWatch.
Selection for inclusion as a "Top 20" site was based solely on web traffic volume. These sites were then evaluated using criteria developed
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https://en.wikipedia.org/wiki/Stem%20cell%20proteomics
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Stem cell proteomics is an omics that analyzes the proteomes of stem cells. Comparing different stem cell proteomes can reveal proteins that are important for stem cell differentiation.
See also
Stem cell genomics
Stem cells
Proteomics
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https://en.wikipedia.org/wiki/Stem%20cell%20chip
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Stem cell chip is a device that detects given biochemical changes in stem cells, for example changes in RNA expression.
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https://en.wikipedia.org/wiki/Waldorf%20doll
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A Waldorf doll (also called Steiner doll) is a form of doll compatible with Waldorf (or Steiner) education philosophies.
The dolls are generally made of natural fibers — such as wool, cotton, or linen — from their stuffing to their hair to their clothing. The doll makers use techniques drawing on traditional European doll-making. The doll's appearance is intentionally simple in order to allow the child playing with it to develop the imagination and creative play. For instance, it has either no facial features, or a simple neutral expression. The legs and arms are soft and if flexible allow natural postures. They are ideally entirely natural.
Dolls vary in the form best suited to the stage of development of the child; from a simple sack or pillow doll for a baby, a knotted or handkerchief style for a teething child, a simple doll with bulky limbs and either short hair or a hat for a toddler. For an older, more independent child who can change clothing and dress hair, 'formed' limbed dolls with the ability to sit are introduced with changeable clothing and often longer hair.
Typically, hair on a Waldorf doll is made of pure wool such as mohair or boucle, ply wool or cotton. Facial feature details on a Waldorf doll vary with the maker and are generally simple stitches, sometimes painted, but are always a simple suggestion and ideally neutral, so the child can imagine the personality and mood of the doll and whether the doll is awake or asleep. Some Waldorf dolls have small suggestions of noses. Skin, eye and mouth colors vary with each doll, ideally to reflect the colouring of the child for a first doll.
See also
Froebel Gifts
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https://en.wikipedia.org/wiki/Heronian%20mean
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In mathematics, the Heronian mean H of two non-negative real numbers A and B is given by the formula
It is named after Hero of Alexandria.
Properties
Just like all means, the Heronian mean is symmetric (it does not depend on the order in which its two arguments are given) and idempotent (the mean of any number with itself is the same number).
The Heronian mean of the numbers A and B is a weighted mean of their arithmetic and geometric means:
Therefore, it lies between these two means, and between the two given numbers.
Application in solid geometry
The Heronian mean may be used in finding the volume of a frustum of a pyramid or cone. The volume is equal to the product of the height of the frustum and the Heronian mean of the areas of the opposing parallel faces.
A version of this formula, for square frusta, appears in the Moscow Mathematical Papyrus from Ancient Egyptian mathematics, whose content dates to roughly 1850 BC.
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https://en.wikipedia.org/wiki/TCP%20window%20scale%20option
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The TCP window scale option is an option to increase the receive window size allowed in Transmission Control Protocol above its former maximum value of 65,535 bytes. This TCP option, along with several others, is defined in which deals with long fat networks (LFNs).
TCP windows
The throughput of a TCP communication is limited by two windows: the congestion window and the receive window. The congestion window tries not to exceed the capacity of the network (congestion control); the receive window tries not to exceed the capacity of the receiver to process data (flow control). The receiver may be overwhelmed by data if for example it is very busy (such as a Web server). Each TCP segment contains the current value of the receive window. If, for example, a sender receives an ack which acknowledges byte 4000 and specifies a receive window of 10000 (bytes), the sender will not send packets after byte 14000, even if the congestion window allows it.
Theory
TCP window scale option is needed for efficient transfer of data when the bandwidth-delay product (BDP) is greater than 64 KB. For instance, if a T1 transmission line of 1.5 Mbit/second was used over a satellite link with a 513 millisecond round-trip time (RTT), the bandwidth-delay product is bits or about 96,187 bytes. Using a maximum buffer size of 64 KB only allows the buffer to be filled to (65,535 / 96,187) = 68% of the theoretical maximum speed of 1.5 Mbit/second, or 1.02 Mbit/s.
By using the window scale option, the receive window size may be increased up to a maximum value of bytes. This is done by specifying a two byte shift count in the header options field. The true receive window size is left shifted by the value in shift count. A maximum value of 14 may be used for the shift count value. This would allow a single TCP connection to transfer data over the example satellite link at 1.5 Mbit/second utilizing all of the available bandwidth.
Essentially, not more than one full transmission window can be
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https://en.wikipedia.org/wiki/McCormick%20Tribune%20Freedom%20Museum
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The McCormick Freedom Museum was the first museum in the United States dedicated to the First Amendment by the McCormick Foundation. It was open from April 11, 2006, until March 1, 2009. The museum offered visitors an interactive experience focused on first amendment rights which include freedom of speech, freedom of religion, freedom of the press, assembly and petition. It was located on Michigan Avenue along the Magnificent Mile next to the historic Tribune Tower.
A sculpture by artists Amy Larimer and Peter Bernheim, titled 12151791 was put into storage when the museum closed. Its title represents the date of December 15, 1791, when the United States Bill of Rights was ratified.
One journalist has noted the irony of a Freedom Museum being named after the Robert R. McCormick, owner of the Chicago Tribune newspaper, saying the name "puts ego before freedom".
A scaled-down mobile version of the museum, dubbed the Freedom Express, made its debut in Chicago's Pioneer Court on May 27, 2010.
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https://en.wikipedia.org/wiki/Tortoiseshell
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Tortoiseshell or tortoise shell is a material produced from the shells of the larger species of tortoise and turtle, mainly the hawksbill sea turtle, which is a critically endangered species according to the IUCN Red List largely because of its exploitation for this trade. The large size, fine color, and unusual form of the hawksbill's scutes make it especially suitable. The distinctive patterning is referred to in names such as the tortoiseshell cat, several breeds of guinea pig, and the common names of several species of the butterfly genera Nymphalis and Aglais, and some other uses.
Uses
Tortoiseshell was widely used from ancient times in the North and in Asia, until the trade was banned in 2014. It was used, normally in thin slices or pieces, in the manufacture of a wide variety of items such as combs, small boxes and frames, inlays in furniture (known as Boulle work carried out by André-Charles Boulle), and other items: frames for spectacles, guitar picks and knitting needles. Despite being expensive, tortoiseshell was attractive to manufacturers and consumers because of its beautiful mottled appearance, its durability, and its organic warmth against the skin.
The initial processing involved separating the layers of the scutes from the animal's carapace by heating, softening the plates by boiling them in salt water and flattening them under a press. Two pieces could be fused by use of a hot iron, but like the earlier stages, great care had to be taken not to lose the color. Finishing and polishing was done by various techniques mainly in Europe or in the US. Craftsmen in various Asian countries have also perfected this art.
Availability
In 1973, the trade of tortoiseshell worldwide was banned under CITES (the Convention on International Trade in Endangered Species). The material was already often imitated in stained horn, plastic like cellulose acetate, and other materials. The synthetic Delrin has been used especially for guitar picks.
Brands of syntheti
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https://en.wikipedia.org/wiki/Bus%20encryption
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Bus encryption is the use of encrypted program instructions on a data bus in a computer that includes a secure cryptoprocessor for executing the encrypted instructions. Bus encryption is used primarily in electronic systems that require high security, such as automated teller machines, TV set-top boxes, and secure data communication devices such as two-way digital radios.
Bus encryption can also mean encrypted data transmission on a data bus from one processor to another processor. For example, from the CPU to a GPU which does not require input of encrypted instructions. Such bus encryption is used by Windows Vista and newer Microsoft operating systems to protect certificates, BIOS, passwords, and program authenticity. PVP-UAB (Protected Video Path) provides bus encryption of premium video content in PCs as it passes over the PCIe bus to graphics cards to enforce digital rights management.
The need for bus encryption arises when multiple people have access to the internal circuitry of an electronic system, either because they service and repair such systems, stock spare components for the systems, own the system, steal the system, or find a lost or abandoned system. Bus encryption is necessary not only to prevent tampering of encrypted instructions that may be easily discovered on a data bus or during data transmission, but also to prevent discovery of decrypted instructions that may reveal security weaknesses that an intruder can exploit.
In TV set-top boxes, it is necessary to download program instructions periodically to customer's units to provide new features and to fix bugs. These new instructions are encrypted before transmission, but must also remain secure on data buses and during execution to prevent the manufacture of unauthorized cable TV boxes. This can be accomplished by secure crypto-processors that read encrypted instructions on the data bus from external data memory, decrypt the instructions in the cryptoprocessor, and execute the instructions
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https://en.wikipedia.org/wiki/Young%20model
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Young model is a radio propagation model that was built on the data collected on New York City. It typically models the behaviour of cellular communication systems in large cities.
Applicable to/under conditions
This model is ideal for modeling the behaviour of cellular communications in large cities with tall structures.
Coverage
Frequency: 150 MHz to 3700 MHz
History
Young model was built on the data of 1952 in New York City.
Mathematical formulation
The mathematical formulation for Young model is:
Where,
L = path loss. Unit: decibel (dB)
GB = gain of base transmitter. Unit: decibel (dB)
GM = gain of mobile transmitter. Unit: decibel (dB)
hB = height of base station antenna. Unit: meter (m)
hM = height of mobile station antenna. Unit: meter (m)
d = link distance. Unit: kilometer (km)
= clutter factor
See also
Hata model
Log-distance path loss model
Radio frequency propagation model
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https://en.wikipedia.org/wiki/Ekphonetic%20notation
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Ekphonetic notation consists of symbols added to certain sacred texts, especially lectionary readings of Biblical texts, as a mnemonic device to assist in their cantillation. Ekphonetic notation can take a number of forms, and has been used in several Jewish and Christian plainchant traditions, but is most commonly associated with Byzantine chant. In many cases, the original meaning of ekphonetic neumes is obscure, and must be reconstructed by comparison with later notation. Joseph Huzaya introduced ekphonetic notation into Syriac in the early 6th century.
See also
Hebrew cantillation
Musical notation
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https://en.wikipedia.org/wiki/Royal%20Zoological%20Society%20of%20Scotland
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The Royal Zoological Society of Scotland is a learned society and registered charity based in Edinburgh, Scotland. It was founded by Thomas Haining Gillespie in 1909. In 1913, Edinburgh Town Council bought a large plot of land on Corstorphine Hill for the society - this later opened to the public as Edinburgh Zoo. The society received its Royal Charter in 1913. The principal objective of the society mentioned in the original charter is:
To promote, facilitate and encourage the study of zoology and kindred subjects and to foster and develop amongst the people an interest in and knowledge of animal life.
In 1986, the society acquired the Highland Wildlife Park in Kingussie, Inverness-shire.
See also
History of Edinburgh Zoo
List of organisations in the United Kingdom with a royal charter
List of zoo associations
Office of the Scottish Charity Regulator
Scottish Wildlife Trust
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https://en.wikipedia.org/wiki/Time-compressed%20speech
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Time-compressed speech refers to an audio recording of verbal text in which the text is presented in a much shorter time interval than it would through normally-paced real time speech. The basic purpose is to make recorded speech contain more words in a given time, yet still be understandable. For example: a paragraph that might normally be expected to take 20 seconds to read, might instead be presented in 15 seconds, which would represent a time-compression of 25% (5 seconds out of 20).
The term "time-compressed speech" should not be confused with "speech compression", which controls the volume range of a sound, but does not alter its time envelope.
Methods
While some voice talents are capable of speaking at rates significantly in excess of general norms, the term "time-compressed speech" most usually refers to examples in which the time-reduction has been accomplished through some form of electronic processing of the recorded speech.
In general, recorded speech can be electronically time-compressed by: increasing its speed (linear compression); removing silences (selective editing); a combination of the two (non-linear compression). The speed of a recording can be increased, which will cause the material to be presented at a faster rate (and hence in a shorter amount of time), but this has the undesirable side-effect of increasing the frequency of the whole passage, raising the pitch of the voices, which can reduce intelligibility.
There are normally silences between words and sentences, and even small silences within certain words, both of which can be reduced or removed ("edited-out") which will also reduce the amount of time occupied by the full speech recording. However, this can also have the effect of removing verbal "punctuation" from the speech, causing words and sentences to run together unnaturally, again reducing intelligibility.
Vowels are typically held a minimum of 20 milliseconds, over many cycles of the fundamental pitch.
DSP systems can
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https://en.wikipedia.org/wiki/Adiabatic%20conductivity
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Adiabatic conductivity is a measure of a material's electrical conductivity, σ, under thermodynamically adiabatic conditions.
See also
Thermodynamics
Thermodynamic properties
Electrical phenomena
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https://en.wikipedia.org/wiki/Empathising%E2%80%93systemising%20theory
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The empathising–systemising (E–S) theory is a theory on the psychological basis of autism and male–female neurological differences originally put forward by English clinical psychologist Simon Baron-Cohen. It classifies individuals based on abilities in empathic thinking (E) and systematic thinking (S). It measures skills using an Empathy Quotient (EQ) and Systemising Quotient (SQ) and attempts to explain the social and communication symptoms in autism spectrum disorders as deficits and delays in empathy combined with intact or superior systemising.
According to Baron-Cohen, the E–S theory has been tested using the Empathy Quotient (EQ) and Systemising Quotient (SQ), developed by him and colleagues, and generates five different 'brain types' depending on the presence or absence of discrepancies between their scores on E or S. E–S profiles show that the profile E>S is more common in females than in males, and the profile S>E is more common in males than in females. Baron-Cohen and associates assert that E–S theory is a better predictor than gender of who chooses STEM subjects (Science, Technology, Engineering and Mathematics). The E–S theory has been extended into the extreme male brain (EMB) theory of autism and Asperger syndrome, which are associated in the E–S theory with below-average empathy and average or above-average systemising.
Baron-Cohen's studies and theory have been questioned on multiple grounds. The overrepresentation of engineers could depend on a socioeconomic status rather than E-S differences.
History
E–S theory was developed by psychologist Simon Baron-Cohen in 2002, as a reconceptualization of cognitive sex differences in the general population. This was done in an effort to understand why the cognitive difficulties in autism appeared to lie in domains in which he says on average females outperformed males, along with why cognitive strengths in autism appeared to lie in domains in which on average males outperformed females. In the first cha
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https://en.wikipedia.org/wiki/Human-based%20evolutionary%20computation
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Human-based evolutionary computation (HBEC) is a set of evolutionary computation techniques that rely on human innovation.
Classes and examples
Human-based evolutionary computation techniques can be classified into three more specific classes analogous to ones in evolutionary computation. There are three basic types of innovation: initialization, mutation, and recombination. Here is a table illustrating which type of human innovation are supported in different classes of HBEC:
All these three classes also have to implement selection, performed either by humans or by computers.
Human-based selection strategy
Human-based selection strategy is a simplest human-based evolutionary computation procedure. It is used heavily today by websites outsourcing collection and selection of the content to humans (user-contributed content). Viewed as evolutionary computation, their mechanism supports two operations: initialization (when a user adds a new item) and selection (when a user expresses preference among items). The website software aggregates the preferences to compute the fitness of items so that it can promote the fittest items and discard the worst ones. Several methods of human-based selection were analytically compared in studies by Kosorukoff and Gentry.
Because the concept seems too simple, most of the websites implementing the idea can't avoid the common pitfall: informational cascade in soliciting human preference. For example, digg-style implementations, pervasive on the web, heavily bias subsequent human evaluations by prior ones by showing how many votes the items already have. This makes the aggregated evaluation depend on a very small initial sample of rarely independent evaluations. This encourages many people to game the system that might add to digg's popularity but detract from the quality of the featured results. It is too easy to submit evaluation in digg-style system based only on the content title, without reading the actual content supposed to be
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https://en.wikipedia.org/wiki/Mathematical%20Optimization%20Society
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The Mathematical Optimization Society (MOS), known as the Mathematical Programming Society until 2010, is an international association of researchers active in optimization. The MOS encourages the research, development, and use of optimization—including mathematical theory, software implementation, and practical applications (operations research).
Founded in , the MOS has several activities: Publishing journals and a newsletter, organizing and cosponsoring conferences, and awarding prizes.
History
In the 1960s, mathematical programming methods were gaining increasing importance both in mathematical theory and in industrial application. To provide a discussion forum for researchers in the field arose, the journal Mathematical Programming was founded in 1970.
Based on activities by George Dantzig, Albert Tucker, Philip Wolfe and others, the MOS was founded in 1973, with George Dantzig as its first president.
Activities
Conferences
Several conferences are organized or co-organized by the Mathematical Optimization Society, for instance:
The International Symposium on Mathematical Programming (ISMP), organized every three years, is open to all fields of mathematical programming.
The Integer Programming and Combinatorial Optimization (IPCO) conference, in Integer programming, is held in those years when there is no ISMP.
The International Conference on Continuous Optimization (ICCOPT), the continuous analog of the IPCO conference, was first held in 2004.
The International Conference on Stochastic Programming (ICSP) takes place every three years and is devoted to optimization using uncertain input data.
The Nordic MOS conference is a biannual meeting of researchers from Scandinavia working in all fields of optimization.
At the Université de Montréal, annual seminars on changing topics are organized by the MOS.
Journals and other publications
There are several publications by the Mathematical Optimization Society:
The journal Mathematical Programming (serie
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https://en.wikipedia.org/wiki/Pasch%27s%20axiom
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In geometry, Pasch's axiom is a statement in plane geometry, used implicitly by Euclid, which cannot be derived from the postulates as Euclid gave them. Its essential role was discovered by Moritz Pasch in 1882.
Statement
The axiom states that,
The fact that segments AC and BC are not both intersected by the line is proved in Supplement I,1, which was written by P. Bernays.
A more modern version of this axiom is as follows:
(In case the third side is parallel to our line, we count an "intersection at infinity" as external.) A more informal version of the axiom is often seen:
History
Pasch published this axiom in 1882, and showed that Euclid's axioms were incomplete. The axiom was part of Pasch's approach to introducing the concept of order into plane geometry.
Equivalences
In other treatments of elementary geometry, using different sets of axioms, Pasch's axiom can be proved as a theorem; it is a consequence of the plane separation axiom when that is taken as one of the axioms. Hilbert uses Pasch's axiom in his axiomatic treatment of Euclidean geometry. Given the remaining axioms in Hilbert's system, it can be shown that Pasch's axiom is logically equivalent to the plane separation axiom.
Hilbert's use of Pasch's axiom
David Hilbert uses Pasch's axiom in his book Foundations of Geometry which provides an axiomatic basis for Euclidean geometry. Depending upon the edition, it is numbered either II.4 or II.5. His statement is given above.
In Hilbert's treatment, this axiom appears in the section concerning axioms of order and is referred to as a plane axiom of order. Since he does not phrase the axiom in terms of the sides of a triangle (considered as lines rather than line segments) there is no need to talk about internal and external intersections of the line with the sides of the triangle ABC.
Caveats
Pasch's axiom is distinct from Pasch's theorem which is a statement about the order of four points on a line. However, in literature there are many in
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https://en.wikipedia.org/wiki/Crime%20Library
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Crime Library was a website documenting major crimes, criminals, trials, forensics, and criminal profiling from books. It was founded in 1998 and was most recently owned by truTV, a cable TV network that is part of Time Warner's Turner Broadcasting System. In August 2014, Crime Library was no longer being updated. In February 2015 the site was taken offline.
Content
Crime Library contained an extensive collection of crime related articles, which were separated into categories: Serial Killers, Notorious Murders, Criminal Mind, Terrorists & Spies and Gangsters & Outlaws. Each category was then broken down into further subcategories. For example, within Serial Killers were the subcategories Most Notorious, Sexual Predators, Truly Weird & Shocking, Unsolved Cases, Partners in Crime and Killers from History. Crime Library also featured photo galleries. These may have had anywhere from 10 to upwards of 100 slides. Some photo galleries were focused on a specific case, while others were lists of crimes linked by a theme (e.g., "Baby for Sale," cases where a person was arrested for allegedly attempting to sell his or her child), or collections of unusual booking photos.
High-profile crimes in the United States were prominent on Crime Library, but the site also contained information about historically notorious characters from various countries, including United Kingdom, Australia and France.
All articles on Crime Library were written exclusively for Crime Library by dozens of commissioned writers, many of them true-crime authors, including Chuck Hustmyre, Katherine Ramsland, Gary C. King and Anthony Bruno.
Crime Library maintained social media features where readers could interact and discuss criminal cases, including a Facebook page, a Twitter account and message boards.
History
Crime Library was founded by Marilyn J. Bardsley in January 1998. Court TV, later truTV, purchased Crime Library in 2001, the same year The Smoking Gun was acquired by Court TV. Originally
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https://en.wikipedia.org/wiki/Artin%E2%80%93Hasse%20exponential
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In mathematics, the Artin–Hasse exponential, introduced by , is the power series given by
Motivation
One motivation for considering this series to be analogous to the exponential function comes from infinite products. In the ring of formal power series Q[[x]] we have the identity
where μ(n) is the Möbius function. This identity can be verified by showing the logarithmic derivative of the two sides are equal and that both sides have the same constant term. In a similar way, one can verify a product expansion for the Artin–Hasse exponential:
So passing from a product over all n to a product over only n prime to p, which is a typical operation in p-adic analysis, leads from ex to Ep(x).
Properties
The coefficients of Ep(x) are rational. We can use either formula for Ep(x) to prove that, unlike ex, all of its coefficients are p-integral; in other words, the denominators of the coefficients of Ep(x) are not divisible by p. A first proof uses the definition of Ep(x) and Dwork's lemma, which says that a power series f(x) = 1 + ... with rational coefficients has p-integral coefficients if and only if f(xp)/f(x)p ≡ 1 mod pZp[[x]]. When f(x) = Ep(x), we have f(xp)/f(x)p = e−px, whose constant term is 1 and all higher coefficients are in pZp.
A second proof comes from the infinite product for Ep(x): each exponent -μ(n)/n for n not divisible by p is a p-integral, and when a rational number a is p-integral all coefficients in the binomial expansion of (1 - xn)a are p-integral by p-adic continuity of the binomial coefficient polynomials t(t-1)...(t-k+1)/k! in t together with their obvious integrality when t is a nonnegative integer (a is a p-adic limit of nonnegative integers) . Thus each factor in the product of Ep(x) has p-integral coefficients, so Ep(x) itself has p-integral coefficients.
The (p-integral) series expansion has radius of convergence 1.
Combinatorial interpretation
The Artin–Hasse exponential is the generating function for the probability a uniforml
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https://en.wikipedia.org/wiki/Sound%20Retrieval%20System
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Sound Retrieval System (SRS) is a patented psychoacoustic 3D audio processing technology originally invented by Arnold Klayman in the early 1980s. The SRS technology applies head-related transfer functions (HRTFs) to create an immersive 3D soundfield using only two speakers, widening the "sweet spot", creating a more spacious sense of ambience, and producing strong localization cues for discrete instruments within an audio mix. SRS is not a Dolby matrix surround decoder but works with normal stereo recordings.
History and technology
Initially Hughes Aircraft, for whom Klayman was doing acoustic consulting at the time, offered a standalone SRS audio processor, as well as licensing the technology to Sony and Thomson (RCA) for inclusion in their products. In the early 1990s, Hughes sold off its non-aerospace-related holdings, and a group of entrepreneurs formed SRS Labs to acquire the SRS technology.
Many TV sets employ built-in SRS to make their built-in audio systems sound "bigger". An article in the November 1994 issue of Consumers Digest magazine tested several SRS-equipped sets from Sony and other manufacturers and concluded that the circuit was essentially a gimmick in these products due to their small, close-set speakers and low-wattage amplifiers. SRS is not a panacea for audio systems that are marginal to begin with; it works best with full-range, high-fidelity sound reproduction.
The company (publicly traded on NASDAQ under the symbol SRSL after a 1996 IPO) since developed or acquired several additional audio technologies, including SRS Headphone, TruSurround XT, TruBass ("psychoacoustic bass enhancement to enable deeper, natural bass of audio source material to be perceived over small speaker drivers"), FOCUS ("sound-image elevation used in combination with SRS to create a large sound image", originally conceived for in-car listening), SRS Virtual Surround, Circle Surround, SRS Wow (an audio-enhancement suite made up of SRS 3D "wide stereo imaging and no
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https://en.wikipedia.org/wiki/National%20Industrial%20Security%20Program
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The National Industrial Security Program, or NISP, is the nominal authority in the United States for managing the needs of private industry to access classified information.
The NISP was established in 1993 by Executive Order 12829. The National Security Council nominally sets policy for the NISP, while the Director of the Information Security Oversight Office is nominally the authority for implementation. Under the ISOO, the Secretary of Defense is nominally the Executive Agent, but the NISP recognizes four different Cognizant Security Agencies, all of which have equal authority: the Department of Defense, the Department of Energy, the Central Intelligence Agency, and the Nuclear Regulatory Commission.
Defense Counterintelligence and Security Agency administers the NISP on behalf of the Department of Defense and 34 other federal agencies.
NISP Operating Manual (DoD 5220.22-M)
A major component of the NISP is the NISP Operating Manual, also called NISPOM, or DoD 5220.22-M. The NISPOM establishes the standard procedures and requirements for all government contractors, with regards to classified information. , the current NISPOM edition is dated 28 Feb 2006. Chapters and selected sections of this edition are:
Chapter 1 – General Provisions and Requirements
Chapter 2 – Security Clearances
Section 1 – Facility Clearances
Section 2 – Personnel Security Clearances
Section 3 – Foreign Ownership, Control, or Influence (FOCI)
Chapter 3 – Security Training and Briefings
Chapter 4 – Classification and Marking
Chapter 5 – Safeguarding Classified Information
Chapter 6 – Visits and Meetings
Chapter 7 – Subcontracting
Chapter 8 – Information System Security
Chapter 9 – Special Requirements
Section 1 – RD and FRD
Section 2 – DoD Critical Nuclear Weapon Design Information (CNWDI)
Section 3 – Intelligence Information
Section 4 – Communication Security (COMSEC)
Chapter 10 – International Security Requirements
Chapter 11 – Miscellaneous Information
Section 1
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https://en.wikipedia.org/wiki/Harmonic%20polynomial
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In mathematics, in abstract algebra, a multivariate polynomial over a field such that the Laplacian of is zero is termed a harmonic polynomial.
The harmonic polynomials form a vector subspace of the vector space of polynomials over the field. In fact, they form a graded subspace. For the real field, the harmonic polynomials are important in mathematical physics.
The Laplacian is the sum of second partials with respect to all the variables, and is an invariant differential operator under the action of the orthogonal group via the group of rotations.
The standard separation of variables theorem states that every multivariate polynomial over a field can be decomposed as a finite sum of products of a radial polynomial and a harmonic polynomial. This is equivalent to the statement that the polynomial ring is a free module over the ring of radial polynomials.
See also
Harmonic function
Spherical harmonics
Zonal spherical harmonics
Multilinear polynomial
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https://en.wikipedia.org/wiki/Radical%20polynomial
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In mathematics, in the realm of abstract algebra, a radical polynomial is a multivariate polynomial over a field that can be expressed as a polynomial in the sum of squares of the variables. That is, if
is a polynomial ring, the ring of radical polynomials is the subring generated by the polynomial
Radical polynomials are characterized as precisely those polynomials that are invariant under the action of the orthogonal group.
The ring of radical polynomials is a graded subalgebra of the ring of all polynomials.
The standard separation of variables theorem asserts that every polynomial can be expressed as a finite sum of terms, each term being a product of a radical polynomial and a harmonic polynomial. This is equivalent to the statement that the ring of all polynomials is a free module over the ring of radical polynomials.
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https://en.wikipedia.org/wiki/Growing%20region
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A growing region also known as a farming region or agricultural region refers to a geographic area characterised by specific climate factors, soil conditions and agricultural practices that are favourable for the cultivation and production of crops, plants, or livestock. Depending on the environmental characteristics, a growing region can be dominated by a single crop or crop combination. For example, the American Corn Belt, the Philippine coconut landscape and the Malayan rubber landscape are examples of growing regions that are dominated by a particular crop. On the other hand, Queensland and New South Wales of Australia characterised by high inherent soil fertility and high seasonal rainfall have highly diverse crop production including wheat, barley, oilseeds, sorghum maize and wheat.
Most crops are cultivated not in one place only, but in several distinct regions in diverse parts of the world. Cultivation in these areas may be enabled by a large-scale regional climate, or by a unique microclimate.
Growing regions, because of the need for climate consistency, are usually oriented along a general latitude, and in the United States these are often called "belts".
The growing region of a traditional staple crop often has a strong cultural cohesiveness.
Examples
The need for growing fodder has also historically limited livestock to certain agricultural regions.
In Viticulture, American Viticultural Area - AVA regions are a specialized geographic type; and European wine appellations of Protected Geographical Status origin are another.
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https://en.wikipedia.org/wiki/Luzin%20N%20property
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In mathematics, a function f on the interval [a, b] has the Luzin N property, named after Nikolai Luzin (also called Luzin property or N property) if for all such that , there holds: , where stands for the Lebesgue measure.
Note that the image of such a set N is not necessarily measurable, but since the Lebesgue measure is complete, it follows that if the Lebesgue outer measure of that set is zero, then it is measurable and its Lebesgue measure is zero as well.
Properties
Any differentiable function has the Luzin N property. This extends to functions that are differentiable on a cocountable set, as the image of a countable set is countable and thus a null set, but not to functions differentiable on a conull set:
The Cantor function does not have the Luzin N property, as the Lebesgue measure of the Cantor set is zero, but its image is the complete [0,1] interval.
A function f on the interval [a,b] is absolutely continuous if and only if it is continuous, is of bounded variation and has the Luzin N property.
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https://en.wikipedia.org/wiki/AAPC%20%28healthcare%29
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The AAPC, previously known by the full title of the American Academy of Professional Coders, is a professional association for people working in specific areas of administration within healthcare businesses in the United States. AAPC is one of a number of providers who offer services such as certification and training to medical coders, medical billers, auditors, compliance managers, and practice managers in the United States. , AAPC has over 190,000 worldwide members, of which nearly 155,000 are certified.
History
The AAPC was founded in 1988, as the American Academy of Professional Coders, with the aim of providing education and certification to coders working in physician-based settings. These settings include group practices and specialty centers (i.e. non-hospital settings). In 2010, as their services had expanded beyond medical and outpatient coding, the full name was dropped in favor of the AAPC initialism.
Products and services
AAPC provides training, certification, and other services to individuals and organizations across medical coding, medical billing, auditing, compliance, and practice management. These services include networking events such as medical coding seminars and conferences.
Certifications
AAPC offers a number of certifications for healthcare professionals, including:
Medical coding and medical billing, including stand-alone certifications in over 20 specialty areas,
Medical auditing
Medical compliance
Physician practice management
See also
Health informatics
Information governance
Medical classification
External links
AAPC official site
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https://en.wikipedia.org/wiki/Coproporphyrinogen%20III%20oxidase
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Coproporphyrinogen-III oxidase, mitochondrial (abbreviated as CPOX) is an enzyme that in humans is encoded by the CPOX gene. A genetic defect in the enzyme results in a reduced production of heme in animals. The medical condition associated with this enzyme defect is called hereditary coproporphyria.
CPOX, the sixth enzyme of the haem biosynthetic pathway, converts coproporphyrinogen III to protoporphyrinogen IX through two sequential steps of oxidative decarboxylation. The activity of the CPOX enzyme, located in the mitochondrial membrane, is measured in lymphocytes.
Function
CPOX is an enzyme involved in the sixth step of porphyrin metabolism it catalyses the oxidative decarboxylation of coproporphyrinogen III to proto-porphyrinogen IX in the haem and chlorophyll biosynthetic pathways. The protein is a homodimer containing two internally bound iron atoms per molecule of native protein. The enzyme is active in the presence of molecular oxygen that acts as an electron acceptor. The enzyme is widely distributed having been found in a variety of eukaryotic and prokaryotic sources.
Structure
Gene
Human CPOX is a mitochondrial enzyme encoded by a 14 kb CPOX gene containing seven exons located on chromosome 3 at q11.2.
Protein
CPOX is expressed as a 40 kDa precursor and contains an amino terminal mitochondrial targeting signal. After proteolytic processing, the protein is present as a mature form of a homodimer with a molecular mass of 37 kDa.
Clinical significance
Hereditary coproporphyria (HCP) and harderoporphyria are two phenotypically separate disorders that concern partial deficiency of CPOX. Neurovisceral symptomatology predominates in HCP. Additionally, it may be associated with abdominal pain and/or skin photosensitivity. Hyper-excretion of coproporphyrin III in urine and faeces has been recorded in biochemical tests. HCP is an autosomal dominant inherited disorder, whereas harderoporphyria is a rare erythropoietic variant form of HCP and is inherited in
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https://en.wikipedia.org/wiki/Porphobilinogen
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Porphobilinogen (PBG) is an organic compound that occurs in living organisms as an intermediate in the biosynthesis of porphyrins, which include critical substances like hemoglobin and chlorophyll.
The structure of the molecule can be described as molecule of pyrrole with sidechains substituted for hydrogen atoms at positions 2, 3 and 4 in the ring (1 being the nitrogen atom); respectively, an aminomethyl group , an acetic acid (carboxymethyl) group , and a propionic acid (carboxyethyl) group .
Biosynthesis
In the first step of the porphyrin biosynthesis pathway, porphobilinogen is generated from aminolevulinate (ALA) by the enzyme ALA dehydratase.
Metabolism
In the typical porphyrin biosynthesis pathway, four molecules of porphobilinogen are concatenated by carbons 2 and 5 of the pyrrole ring (adjacent to the nitrogen atom) into hydroxymethyl bilane by the enzyme porphobilinogen deaminase, also known as hydroxymethylbilane synthase.
Pathologies
Acute intermittent porphyria causes an increase in urinary porphobilinogen.
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https://en.wikipedia.org/wiki/Rayl
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A Rayl, rayl or Rayleigh is one of two units of specific acoustic impedance or, equivalently, characteristic acoustic impedance; one an MKS unit, and the other a CGS unit. These have the same dimensions as momentum per volume.
The units are named after John William Strutt, 3rd Baron Rayleigh. They are not to be confused with the rayleigh unit of photon flux, which is used to measure airglow and is named after his son, Robert John Strutt, 4th Baron Rayleigh.
Explanation
Specific acoustic impedance
When sound waves pass through any physical substance the pressure of the waves causes the particles of the substance to move. The sound specific impedance is the ratio between the sound pressure and the particle velocity it produces.
Specific acoustic impedance is defined as:
where and are the specific acoustic impedance, pressure and particle velocity phasors, is the position and is the frequency.
Characteristic acoustic impedance
The Rayl is also used for the characteristic (acoustic) impedance of a medium, which is an inherent property of a medium:
Here is the characteristic impedance, and and are the density and speed of sound in the unperturbed medium (i.e. when there are no sound waves travelling in it).
In a viscous medium, there will be a phase difference between the pressure and velocity, so the specific acoustic impedance will be different from the characteristic acoustic impedance .
MKS and CGS units
The MKS unit and the CGS unit confusingly have the same name, but not the same value:
In MKS units, 1 Rayl equals 1 pascal-second per meter (Pa·s·m−1), or equivalently 1 newton-second per cubic meter (N·s·m−3). In SI base units, that is kg·s−1·m−2.
In CGS units, 1 Rayl equals 1 barye-second per centimeter (ba·s·cm−1), or equivalently 1 dyne-second per cubic centimeter (dyn·s·cm−3). In CGS base units, that is g·s−1·cm−2.
1 CGS Rayl = 10 MKS Rayl. In other words, a CGS Rayl is ten times larger than an MKS Rayl.
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https://en.wikipedia.org/wiki/Coproporphyrinogens
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Coproporphyrinogens are tetrapyrroles with four propionic acid groups and an equal number of substituted methyls.
Coproporphyrinogen III is the most common variance. In the metabolism of porphyrin, it is formed from uroporphyrinogen III by the enzyme uroporphyrinogen III decarboxylase, and it is converted into protoporphyrinogen IX by coproporphyrinogen III oxidase.
External links
PubChem - Coproporphyrinogen III
Pyrroles
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https://en.wikipedia.org/wiki/Uroporphyrinogen
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Uroporphyrinogens are cyclic tetrapyrroles with four propionic acid groups ("P" groups) and four acetic acid groups ("A" groups).
There are four forms, which vary based upon the arrangements of the "P" and "A" groups (in clockwise order):
In the "I" variety (i.e. uroporphyrinogen I), the order repeats four times: AP-AP-AP-AP.
In the "III" variety (i.e. uroporphyrinogen III), the fourth is reversed: AP-AP-AP-PA.
This is the most common form. In the synthesis of porphyrin, it is created from the linear tetrapyrrole hydroxymethylbilane by the enzyme uroporphyrinogen III synthase, and is further converted into coproporphyrinogen III by the enzyme uroporphyrinogen III decarboxylase.
The "II" and "IV" varieties can be created synthetically, but do not appear in nature.
External links
Biomolecules
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https://en.wikipedia.org/wiki/Virtuoso%20Universal%20Server
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Virtuoso Universal Server is a middleware and database engine hybrid that combines the functionality of a traditional relational database management system (RDBMS), object–relational database (ORDBMS), virtual database, RDF, XML, free-text, web application server and file server functionality in a single system. Rather than have dedicated servers for each of the aforementioned functionality realms, Virtuoso is a "universal server"; it enables a single multithreaded server process that implements multiple protocols. The free and open source edition of Virtuoso Universal Server is also known as OpenLink Virtuoso. The software has been developed by OpenLink Software with Kingsley Uyi Idehen and Orri Erling as the chief software architects.
Database structure
Core database engine
Virtuoso provides an extended object–relational model, which combines the flexibility of relational access with inheritance, run time data typing, late binding, and identity-based access. Virtuoso Universal Server database includes physical file and in memory storage and operating system processes that interact with the storage. There is one main process, which has listeners on a specified port for HTTP, SOAP, and other protocols.
Architecture
Virtuoso is designed to take advantage of operating system threading support and multiple CPUs. It consists of a single process with an adjustable pool of threads shared between clients. Multiple threads may work on a single index tree with minimal interference with each other. One cache of database pages is shared among all threads and old dirty pages are written back to disk as a background process.
The database has at all times a clean checkpoint state and a delta of committed or uncommitted changes to this checkpointed state. This makes it possible to do a clean backup of the checkpoint state while transactions proceed on the commit state.
A transaction log file records all transactions since the last checkpoint. Transaction log files may be pr
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https://en.wikipedia.org/wiki/Direct%20read%20after%20write
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Direct read after write is a procedure that compares data recorded onto a medium against the source. A typical example would be CD burning software which reads a CD-ROM once it has been burned onto, effectively ensuring that data written is the same as the data it was copied from.
External links
Smart Computing Dictionary entry
Storage software
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