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https://en.wikipedia.org/wiki/Anthrax%20Vaccine%20Immunization%20Program | The Anthrax Vaccine Immunization Program (AVIP), is the name of the policy set forth by the U.S. federal government to immunize its military and certain civilian personnel with BioThrax, an anthrax vaccine manufactured by Emergent BioSolutions Inc. It was set up by the Clinton administration.
In June 2001, the program was halted by the DoD due to changes in the manufacturing process not approved by the Food and Drug Administration (FDA). In the wake of the 2001 anthrax attacks and long after the 2003 invasion of Iraq, all military personnel were required to receive the anthrax vaccine. In Court, it was ruled that vaccination could not be forced on military personnel without a special order by the president. Thereafter it ran into and judicial obstacles (mainly concerning the methods and viability of the vaccine).
Between March 1998 and December 2008, nearly 8 million doses of BioThrax were administered to over 2 million U.S. military personnel as part of the program. In December 2008, the FDA approved a new version of BioThrax which requires five intramuscular doses instead of six subcutaneous doses.
Overview
The vaccination requirement was instituted in 1998 because of concerns that anthrax could be used as a biological weapon (see anthrax weaponization). Secretary of Defense William Cohen stated that "anthrax poses a clear and present danger to our armed forces. It is the weapon of choice for germ warfare because it is easy to weaponize and is as lethal as the Ebola virus." Anthrax had previously been used in warfare as early as World War I, against livestock, and was also tested during World War II by Japan, against Chinese civilian populations, and by the US, Canada, and Great Britain on sheep at Gruinard Island. The Japanese attack was part of a larger program of biological warfare and human experimentation that is estimated to have killed 580,000 people. The Soviet Union weaponized anthrax, and 64 people were killed in an acc |
https://en.wikipedia.org/wiki/Shift%20matrix | In mathematics, a shift matrix is a binary matrix with ones only on the superdiagonal or subdiagonal, and zeroes elsewhere. A shift matrix U with ones on the superdiagonal is an upper shift matrix. The alternative subdiagonal matrix L is unsurprisingly known as a lower shift matrix. The (i,j):th component of U and L are
where is the Kronecker delta symbol.
For example, the 5×5 shift matrices are
Clearly, the transpose of a lower shift matrix is an upper shift matrix and vice versa.
As a linear transformation, a lower shift matrix shifts the components of a column vector one position down, with a zero appearing in the first position. An upper shift matrix shifts the components of a column vector one position up, with a zero appearing in the last position.
Premultiplying a matrix A by a lower shift matrix results in the elements of A being shifted downward by one position, with zeroes appearing in the top row. Postmultiplication by a lower shift matrix results in a shift left.
Similar operations involving an upper shift matrix result in the opposite shift.
Clearly all finite-dimensional shift matrices are nilpotent; an n by n shift matrix S becomes the null matrix when raised to the power of its dimension n.
Shift matrices act on shift spaces. The infinite-dimensional shift matrices are particularly important for the study of ergodic systems. Important examples of infinite-dimensional shifts are the Bernoulli shift, which acts as a shift on Cantor space, and the Gauss map, which acts as a shift on the space of continued fractions (that is, on Baire space.)
Properties
Let L and U be the n by n lower and upper shift matrices, respectively. The following properties hold for both U and L.
Let us therefore only list the properties for U:
det(U) = 0
trace(U) = 0
rank(U) = n − 1
The characteristic polynomials of U is
Un = 0. This follows from the previous property by the Cayley–Hamilton theorem.
The permanent of U is 0.
The following properties show how |
https://en.wikipedia.org/wiki/Green%27s%20function%20%28many-body%20theory%29 | In many-body theory, the term Green's function (or Green function) is sometimes used interchangeably with correlation function, but refers specifically to correlators of field operators or creation and annihilation operators.
The name comes from the Green's functions used to solve inhomogeneous differential equations, to which they are loosely related. (Specifically, only two-point 'Green's functions' in the case of a non-interacting system are Green's functions in the mathematical sense; the linear operator that they invert is the Hamiltonian operator, which in the non-interacting case is quadratic in the fields.)
Spatially uniform case
Basic definitions
We consider a many-body theory with field operator (annihilation operator written in the position basis) .
The Heisenberg operators can be written in terms of Schrödinger operators as
and the creation operator is , where is the grand-canonical Hamiltonian.
Similarly, for the imaginary-time operators,
[Note that the imaginary-time creation operator is not the Hermitian conjugate of the annihilation operator .]
In real time, the -point Green function is defined by
where we have used a condensed notation in which signifies and signifies . The operator denotes time ordering, and indicates that the field operators that follow it are to be ordered so that their time arguments increase from right to left.
In imaginary time, the corresponding definition is
where signifies . (The imaginary-time variables are restricted to the range from to the inverse temperature .)
Note regarding signs and normalization used in these definitions: The signs of the Green functions have been chosen so that Fourier transform of the two-point () thermal Green function for a free particle is
and the retarded Green function is
where is the Matsubara frequency.
Throughout, is for bosons and for fermions and denotes either a commutator or anticommutator as appropriate.
(See below for details.)
Two-point functions
The |
https://en.wikipedia.org/wiki/Congruent%20melting | Congruent melting occurs during melting of a compound when the composition of the liquid that forms is the same as the composition of the solid. It can be contrasted with incongruent melting. This generally happens in two-component systems. To take a general case, let A and B be the two components and AB a stable solid compound formed by their chemical combination. If we draw a phase diagram for the system, we notice that there are three solid phases, namely A, B and compound AB. Accordingly, there will be three fusion or freezing point curves AC, BE and CDE for the three solid phases. In the phase diagram, we can notice that the top point D of the phase diagram is the congruent melting point of the compound AB because the solid and liquid phases now have the same composition. Evidently, at this temperature, the two-component system has become a one-component system because both solid and liquid phases contains only the compound AB.
Congruent melting point represents a definite temperature just like the melting points of pure components. In some phase diagrams, the congruent melting point of a compound AB may lie above the melting points of pure components A and B. But it is not always necessarily the case. There are different types of systems known in which the congruent melting point is observed below the melting points of the pure components. This happens for inter-metallic compounds, for example, for .
See also
Congruent transition
Incongruent melting
Phase diagram
Phase rule |
https://en.wikipedia.org/wiki/Myriad%20Genetics | Myriad Genetics, Inc. is an American genetic testing and precision medicine company based in Salt Lake City, Utah, United States. Myriad employs a number of proprietary technologies that permit doctors and patients to understand the genetic basis of human disease and the role that genes play in the onset, progression and treatment of disease. This information is used to guide the development of new products that assess an individual's risk for developing disease later in life (predictive medicine), identify a patient's likelihood of responding to a particular drug therapy (precision medicine), assess a patient's risk of disease progression and disease recurrence (precision medicine), and measure disease activity.
History
The global search for the genetic basis of breast cancer began when Mary-Claire King, Ph.D., from the University of California, Berkeley announced the localization through linkage analysis of a gene associated with increased risk for breast cancer (BRCA1) to the long arm of chromosome 17.
To further locate the actual gene, Dr. Skolnick and his colleagues invented a gene mapping technique known as Restriction Fragment-length Polymorphisms (RFLP). Gilbert joined Kimberlin in 1991, and they teamed up with Skolnick to form Myriad Genetics.
In August 1994, Mark Skolnick and researchers at Myriad, along with colleagues at the University of Utah, the U.S. National Institutes of Health (NIH), and McGill University sequenced BRCA1. They attempted to patent this gene, which resulted in significant controversy and a landmark Supreme Court Case.
The firm then established the first clinical laboratory to commercialize genomic testing. Myriad created the first test to measure the molecular biology and aggressiveness of men’s prostate cancer, devised a method to assess the inherited breast cancer risk of any woman not previously diagnosed with breast cancer, regardless of ancestry, important for addressing racial and ethnic disparities, commercialized a psyc |
https://en.wikipedia.org/wiki/Pequi%20oil | Pequi oil is a seed oil, extracted from the seeds of the Caryocar brasiliense, which is native to Brazil. The pale yellow mesocarp oil is extracted and used directly as a cooking oil. In Brazil, there are projects among indigenous people groups to develop pequi oil production as a means of economic development.
Pequi oil contains 44.2% palmitic and 51.7% oleic acid, with linolenic and stearic acids in much smaller amounts. |
https://en.wikipedia.org/wiki/Left%20triangular%20ligament | The left triangular ligament is a large peritoneal fold. It connects the posterior part of the upper surface of the left lobe of the liver to the thoracic diaphragm.
Structure
The left triangular ligament connects the posterior part of the upper surface of the left lobe of the liver to the thoracic diaphragm. Its anterior layer is continuous with the left layer of the falciform ligament.
Additional images |
https://en.wikipedia.org/wiki/Right%20triangular%20ligament | The right triangular ligament is situated at the right extremity of the bare area, and is a small fold which passes to the diaphragm, being formed by the apposition of the upper and lower layers of the coronary ligament.
Additional images |
https://en.wikipedia.org/wiki/Insensitive%20nuclei%20enhanced%20by%20polarization%20transfer | Insensitive nuclei enhancement by polarization transfer (INEPT) is a signal enhancement method used in NMR spectroscopy. It involves the transfer of nuclear spin polarization from spins with large Boltzmann population differences to nuclear spins of interest with lower Boltzmann population differences. INEPT uses J-coupling for the polarization transfer in contrast to Nuclear Overhauser effect (NOE), which arises from dipolar cross-relaxation. This method of signal enhancement was introduced by Ray Freeman in 1979. Due to its usefulness in signal enhancement, pulse sequences used in heteronuclear NMR experiments often contain blocks of INEPT or INEPT-like sequences.
Background
The sensitivity of NMR signal detection depends on the gyromagnetic ratio (γ) of the nucleus. In general, the signal intensity produced from a nucleus with a gyromagnetic ratio of γ is proportional to γ3 because the magnetic moment, the Boltzmann populations, and the nuclear precession frequency all increase in proportion to the gyromagnetic ratio γ. For example, the gyromagnetic ratio of 13C is 4 times lower than that of 1H, so the signal intensity it produces will be 64 times lower than one produced by a proton. However, since noise also increases as the square root of the frequency, the sensitivity is roughly proportional to γ5/2. A 13C nucleus would be 32 times less sensitive than a proton, and 15N around 300 times less sensitive. Sensitivity enhancement techniques are therefore desirable when recording an NMR signal from an insensitive nucleus.
The sensitivity can be enhanced artificially by increasing the Boltzmann factors. One method may be through NOE; for example, for 13C signal, the signal-to-noise ratio can be improved three-fold when the attached protons are saturated. However, for NOE, a negative value of K, the ratio of gyromagnetic ratios of the nuclei, may result in a reduction in signal intensity. Since15N has a negative gyromagnetic ratio, the observed 15N signal can |
https://en.wikipedia.org/wiki/Fly-whisk |
A fly-whisk (or fly-swish) is a tool that is used to swat flies. A similar device is used as a hand fan in hot tropical climates, sometimes as part of regalia, and is called a chowrie, chāmara, or prakirnaka in South Asia and Tibet.
In Indonesian art, a fly-whisk is one of the items that is associated with Shiva. A fly-whisk is frequently seen as an attribute of Hindu, Jain, Daoist and Buddhist deities. The fly-whisk is evident in some configurations of the Ashtamangala, employed in some traditions of murti puja, particularly Gaudiya Vaishnavism. It is also used as an accessory in the ritual aspects of folk performance traditions, especially folk-theater forms like Pala Gaan, where it can double as a prop.
Fly-whisks are in use in parts of the contemporary Middle East, such as Egypt, by some classes of society, e.g., outdoor merchants and shop keepers, especially in summer when flies become bothersome. Those have a wooden handle and plant fibers attached to them. The more expensive ones are made from horse hair. In the eastern parts of the Indian subcontinent, it is made from the tail-hairs of the yak. Yakut people from Siberia use fly-whisk called deybiir made of horse tail both for swating mosquitoes and as a sacred tool for shamanistic rituals.
Fly-whisks appear frequently in the traditional regales of monarchs and nobility in many parts of the African continent. Fly whisks, called "ìrùkẹ̀rẹ̀" in Yoruba, were used by Yoruba monarchs and chiefs as a symbol of power and respect. This use has sometimes carried on into modern contexts: Kenyan leader Jomo Kenyatta carried a fly-whisk, a mark of authority in Maasai society, as did Malawian leader Hastings Banda, while South African jazz musician Jabu Khanyile also used a Maasai fly-whisk as a trademark when on stage. The fly-whisk is one of the traditional symbols of Buddhist monastic hierarchy in China and Japan, along with the khakkhara, jewel scepter, and begging bowl. The fly-whisk in Buddhism represents the s |
https://en.wikipedia.org/wiki/Adjoint%20filter | In signal processing, the adjoint filter mask of a filter mask is reversed in time and the elements are complex conjugated.
Its name is derived from the fact that the convolution with the adjoint filter is the adjoint operator of the original filter, with respect to the Hilbert space of the sequences in which the inner product is the Euclidean norm.
The autocorrelation of a signal can be written as .
Properties |
https://en.wikipedia.org/wiki/Institutional%20model%20theory | This page is about the concept in mathematical logic. For the concepts in sociology, see Institutional theory and Institutional logic.
In mathematical logic, institutional model theory generalizes a large portion of first-order model theory to an arbitrary logical system.
Overview
The notion of "logical system" here is formalized as an institution. Institutions constitute a model-oriented meta-theory on logical systems similar to how the theory of rings and modules constitute a meta-theory for classical linear algebra. Another analogy can be made with universal algebra versus groups, rings, modules etc. By abstracting away from the realities of the actual conventional logics, it can be noticed that institution theory comes in fact closer to the realities of non-conventional logics.
Institutional model theory analyzes and generalizes classical model-theoretic notions and results, like
elementary diagrams
elementary embeddings
ultraproducts, Los' theorem
saturated models
axiomatizability
varieties, Birkhoff axiomatizability
Craig interpolation
Robinson consistency
Beth definability
Gödel's completeness theorem
For each concept and theorem, the infrastructure and properties required are analyzed and formulated as conditions on institutions, thus providing a detailed insight to which properties of first-order logic they rely on and how much they can be generalized to other logics. |
https://en.wikipedia.org/wiki/Radio%20software | Almost all radio stations today use some form of broadcast automation. Although some only use small scripts in audio players, a more robust solution is using a full radio automation suite. There are many commercial and free radio automation packages available.
Radio software history
Radio software allows AM and FM broadcasting to reproduce music and voices from the computer’s hard disk instead of using CD, MD, tape recorders or the old cartridge tape (see Fidelipac). Usually the radio stations stores all advertising campaigns and most of the music in hard disk. Then, instant replay of all the recorded material is done from a keyboard or with a click of the mouse. Now the PC is part of every AM and FM broadcasting, webcasting or podcasting system around the world.
Radio software not only reproduces audio. It is possible to create a “playlist” that can reproduce automatically, without a board operator, a complete radio program, including meteorological announces, advertising campaigns, music tunes, satellite network connection, etc. Then, 24 hours radio stations are possible, also in small towns that can not afford to have operators and speakers all around the clock. Standard PCs are connected in a LAN network to be used on the master control, production, news, administration, etc.
This technology is claimed to be invented in Buenos Aires by Oscar Bonello in 1989. The first radio software for automation, using lossy compressed digital audio codecs, was named Audicom and was internationally introduced at the 1990 National Association of Broadcasters Convention in Atlanta, USA. The world's first radio station to use it was one in San Francisco, California. The basis of the Audicom was the first application, targeted at radio automation, of the audio bit compression technology used to reduce the amount of data. Bonello delivered the first radio automation working technology using the masking curves published by Richard Ehmer.
See also earlier developments of a mu |
https://en.wikipedia.org/wiki/Algebraic%20logic | In mathematical logic, algebraic logic is the reasoning obtained by manipulating equations with free variables.
What is now usually called classical algebraic logic focuses on the identification and algebraic description of models appropriate for the study of various logics (in the form of classes of algebras that constitute the algebraic semantics for these deductive systems) and connected problems like representation and duality. Well known results like the representation theorem for Boolean algebras and Stone duality fall under the umbrella of classical algebraic logic .
Works in the more recent abstract algebraic logic (AAL) focus on the process of algebraization itself, like classifying various forms of algebraizability using the Leibniz operator .
Calculus of relations
A homogeneous binary relation is found in the power set of for some set X, while a heterogeneous relation is found in the power set of , where . Whether a given relation holds for two individuals is one bit of information, so relations are studied with Boolean arithmetic. Elements of the power set are partially ordered by inclusion, and lattice of these sets becomes an algebra through relative multiplication or composition of relations.
"The basic operations are set-theoretic union, intersection and complementation, the relative multiplication, and conversion."
The conversion refers to the converse relation that always exists, contrary to function theory. A given relation may be represented by a logical matrix; then the converse relation is represented by the transpose matrix. A relation obtained as the composition of two others is then represented by the logical matrix obtained by matrix multiplication using Boolean arithmetic.
Example
An example of calculus of relations arises in erotetics, the theory of questions. In the universe of utterances there are statements S and questions Q. There are two relations and α from Q to S: q α a holds when a is a direct answer to question q. The oth |
https://en.wikipedia.org/wiki/Dispersion%20%28geology%29 | Dispersion is a process that occurs in soils that are particularly vulnerable to erosion by water. In soil layers where clays are saturated with sodium ions ("sodic soils"), soil can break down very easily into fine particles and wash away. This can lead to a variety of soil and water quality problems, including:
large soil losses by gully erosion and tunnel erosion
Soil structural degradation, clogging and sealing where dispersed particles settle
Suspended soil causing turbidity in water and transporting nutrients off the land.
Identifying dispersive soils
Dispersive soils are more common in older landscapes where leaching and illuviation processes have had more time to work. A source of sodium is also required. Possible sources can include weathering from soil parent materials or wind-blown salt deposition. Sodium ions are highly mobile in the soil solution and so they accumulate in the lower parts of the landscape.
The dispersive portion of a soil profile is generally confined to the subsoil, where soil-forming processes concentrate clay minerals and sodium. This means that dispersive soils may not be identified until they are disturbed in a way that exposes the subsoil to running water.
When observed in situ, dispersive soil textures may feel 'soapy', and in many cases the physical structure of subsoil layers will be prismatic or columnar. A simplified version of the Emerson soil dispersion test can be completed in the field on a 20-minute to two-hour timescale.
Laboratory tests used to diagnose a soil as dispersive focus on the cation exchange capacity of a soil sample and its cation breakdown. Soil cations are dominated by Ca2+, Mg2+, K+, and Na+, as well as H+ in acidic soils. The exchangeable sodium percentage ( "ESP", (sodium / (total cations)) * 100 ) is a key indicator derived from these measurements. Where ESP exceeds 5%, dispersive behaviour becomes possible, and is highly likely where ESP exceeds 15%.
Managing dispersive soils
The best manageme |
https://en.wikipedia.org/wiki/Renal%20hilum | The renal hylus (Latin: hylus renale) or renal pedicle is the hylus of the kidney, that is, its recessed central fissure where its vessels, nerves and ureter pass. The medial border of the kidney is concave in the center and convex toward either extremity; it is directed forward and a little downward. Its central part presents a deep longitudinal fissure, bounded by prominent overhanging anterior and posterior lips. This fissure is a hylus that transmits the vessels, nerves, and ureter. From anterior to posterior, the renal vein exits, the renal artery enters, and the renal pelvis exits the kidney.
On the left hand side the hylus is located at the L1 vertebral level and the right kidney at level L1-2. The lower border of the kidneys is usually alongside L3.
Hylus's Order
The superior, middle, and inferior vessels enter or leave the hylus of kidney: from anterior to posterior is renal vein, renal artery and renal pelvis, respectively.
See also
Renal artery
Renal vein
Renal pyramids
Renal medulla
Additional images |
https://en.wikipedia.org/wiki/Polyphase%20matrix | In signal processing, a polyphase matrix is a matrix whose elements are filter masks. It represents a filter bank as it is used in sub-band coders alias discrete wavelet transforms.
If are two filters, then one level the traditional wavelet transform maps an input signal to two output signals , each of the half length:
Note, that the dot means polynomial multiplication; i.e., convolution and means downsampling.
If the above formula is implemented directly, you will compute values that are subsequently flushed by the down-sampling. You can avoid their computation by splitting the filters and the signal into even and odd indexed values before the wavelet transformation:
The arrows and denote left and right shifting, respectively. They shall have the same precedence like convolution, because they are in fact convolutions with a shifted discrete delta impulse.
The wavelet transformation reformulated to the split filters is:
This can be written as matrix-vector-multiplication
This matrix is the polyphase matrix.
Of course, a polyphase matrix can have any size, it need not to have square shape. That is, the principle scales well to any filterbanks, multiwavelets, wavelet transforms based on fractional refinements.
Properties
The representation of sub-band coding by the polyphase matrix is more than about write simplification. It allows the adaptation of many results from matrix theory and module theory. The following properties are explained for a matrix, but they scale equally to higher dimensions.
Invertibility/perfect reconstruction
The case that a polyphase matrix allows reconstruction of a processed signal from the filtered data, is called perfect reconstruction property. Mathematically this is equivalent to invertibility. According to the theorem of invertibility of a matrix over a ring, the polyphase matrix is invertible if and only if the determinant of the polyphase matrix is a Kronecker delta, which is zero everywhere except for one |
https://en.wikipedia.org/wiki/Fantastico%20%28web%20hosting%29 | Fantastico is a commercial script library that automates the installation of web applications to a website. Fantastico scripts are executed from the administration area of a website control panel such as cPanel. Fantastico's web site claims that they are installed on ten thousand servers, with a million users worldwide.
Fantastico scripts are usually executed when a new website is created, or a new application is added to an existing website. The scripts typically create tables in a database, install software, adjust permissions, and modify web server configuration files. Although Fantastico primarily targets open-source software, a handful of scripts are also available that install proprietary products. Once installed, these are available to all the domains hosted by a physical server; such as website builder SohoLaunch, PerlDesk customer support software, and AccountLab Plus software for interacting with Internet registrars.
There are more than 650 applications that have Fantastico scripts associated with them.
See also
cPanel – One of the platforms on which Fantastico runs.
installapp – Script Installer for Kloxo
Installatron
Softaculous |
https://en.wikipedia.org/wiki/Telectroscope | The telectroscope (also referred to as 'electroscope') was the first conceptual model of a television or videophone system. The term was used in the 19th century to describe science-based systems of distant seeing.
The name and its concept came into being not long after the telephone was patented in 1876, and its original concept evolved from that of remote facsimile reproductions onto paper, into the live viewing of remote images.
Figuier's imaginary telectroscope
The term "telectroscope" was used by the French writer and publisher Louis Figuier in 1878 to popularize an invention wrongly interpreted as real and incorrectly ascribed to Alexander Graham Bell. Figuier was probably misled by the article "The Electroscope" published in The New York Sun of 30 March 1877. Written under the pseudonym "Electrician", the New York Sun article claimed that "an eminent scientist", whose name had to be withheld, had invented a device whereby objects or people anywhere in the world "could be seen anywhere by anybody". According to the article, the device would allow merchants to transmit pictures of their wares to their customers, the contents of museum collections would be made available to scholars in distant cities, and (combined with the telephone) operas and plays could be broadcast into people's homes.
In reality, the imagined "telectroscopes" described in the articles had nothing to do with the device being developed by Dr. Bell and his assistant Charles Sumner Tainter which was christened with the ambiguous name photophone. The photophone was actually a wireless optical telephone that conveyed audio conversations on modulated lightbeams, the precursor for today's fiber-optic communications. Bell and Tainter would receive several patents in 1880/1881 for their then cutting-edge invention (master ), which used the same selenium materials in its receivers that created the initial excitement surrounding the telectroscope's proposals.
Further developments
Neverthel |
https://en.wikipedia.org/wiki/Query%20expansion | Query expansion (QE) is the process of reformulating a given query to improve retrieval performance in information retrieval operations, particularly in the context of query understanding.
In the context of search engines, query expansion involves evaluating a user's input (what words were typed into the search query area, and sometimes other types of data) and expanding the search query to match additional documents. Query expansion involves techniques such as:
Finding synonyms of words, and searching for the synonyms as well
Finding semantically related words (e.g. antonyms, meronyms, hyponyms, hypernyms)
Finding all the various morphological forms of words by stemming each word in the search query
Fixing spelling errors and automatically searching for the corrected form or suggesting it in the results
Re-weighting the terms in the original query
Query expansion is a methodology studied in the field of computer science, particularly within the realm of natural language processing and information retrieval.
Precision and recall trade-offs
Search engines invoke query expansion to increase the quality of user search results. It is assumed that users do not always formulate search queries using the best terms. Best in this case may be because the database does not contain the user entered terms.
By stemming a user-entered term, more documents are matched, as the alternate word forms for a user entered term are matched as well, increasing the total recall. This comes at the expense of reducing the precision. By expanding a search query to search for the synonyms of a user entered term, the recall is also increased at the expense of precision. This is due to the nature of the equation of how precision is calculated, in that a larger recall implicitly causes a decrease in precision, given that factors of recall are part of the denominator. It is also inferred that a larger recall negatively impacts overall search result quality, given that many users do no |
https://en.wikipedia.org/wiki/Highway%20Encounter | Highway Encounter is a video game published for the ZX Spectrum, Amstrad CPC, MSX, Commodore 64, Sharp MZ, and Tatung Einstein by Vortex Software in 1985. It was written by Costa Panayi who also coded Android, Android Two, TLL, Cyclone, and Revolution.
Summary
Highway Encounter is a strategy/action game played from a 3D isometric perspective in which you must successfully chaperone a bomb along a long, straight stretch of highway and into the alien base at the end of it. There are thirty screens to pass through and most are filled with hazards that threaten to block your progress (such as barrels) or destroy you (aliens and explosive mines).
Players control a robotic "Vorton" (resembling a dalek from Doctor Who) and one of the features that provides Highway Encounter with its unique appeal is that the bomb is constantly being pushed onwards by your extra lives - four more Vortons, who accompany you along the highway. A key strategic element to the game is for the player character to travel several screens ahead of the bomb to clear a safe path for it; normally this would be done by temporarily blocking the bomb's forward motion. However, if the bomb is left in an unsafe location, it is possible for all your extra lives to be lost without the player character being destroyed once. Once all spare lives are lost, the player character must manually push the bomb.
Reception
The Spectrum version of the game was voted number 40 in the Your Sinclair Official Top 100 Games of All Time.
Legacy
There is an unfinished and officially unreleased, but available to download version for Atari ST made by Mark Haigh-Hutchinson and graphics by Costa Panayi, from 1990. Versions for Amiga and Sega Mega Drive were also planned but Hutchinson stated that the Mega Drive version was left unpublished.
Highway Encounter was followed by a sequel, Alien Highway, in 1986. |
https://en.wikipedia.org/wiki/Spread%20of%20a%20matrix | In mathematics, and more specifically matrix theory, the spread of a matrix is the largest distance in the complex plane between any two eigenvalues of the matrix.
Definition
Let be a square matrix with eigenvalues . That is, these values are the complex numbers such that there exists a vector on which acts by scalar multiplication:
Then the spread of is the non-negative number
Examples
For the zero matrix and the identity matrix, the spread is zero. The zero matrix has only zero as its eigenvalues, and the identity matrix has only one as its eigenvalues. In both cases, all eigenvalues are equal, so no two eigenvalues can be at nonzero distance from each other.
For a projection, the only eigenvalues are zero and one. A projection matrix therefore has a spread that is either (if all eigenvalues are equal) or (if there are two different eigenvalues).
All eigenvalues of a unitary matrix lie on the unit circle. Therefore, in this case, the spread is at most equal to the diameter of the circle, the number 2.
The spread of a matrix depends only on the spectrum of the matrix (its multiset of eigenvalues). If a second matrix of the same size is invertible, then has the same spectrum as . Therefore, it also has the same spread as .
See also
Field of values |
https://en.wikipedia.org/wiki/List%20of%20Foucault%20pendulums | This is a list of Foucault pendulums in the world:
Europe
Austria
Technisches Museum Wien, Vienna
St. Ruprecht an der Raab, Styria, erected in 2001 in a slim stainless steel pyramid, partially with glass windows; it is worldwide the first to exist outside a closed building: on the street. - Length: 6.5 m, weight: 32 kg
Belarus
Belarus State Pedagogic University, Minsk
Belgium
Volkssterrenwacht Mira, Grimbergen
Technopolis, Mechelen
Festraetsstudio, Sint-Truiden
UGent-volkssterrenwacht Armand Pien Ghent
Bulgaria
Public Astronomical Observatory and Planetarium "Nicolaus Copernicus", Varna - Length: 14.4 m
Czech Republic
Observatory and Planetarium Hradec Králové, Hradec Králové - Length: 10 m, weight: 8.5 kg
Czech Technical University, Prague - Length: 21 m, weight: 34 kg
Rotunda in Castle Flower Garden, Kroměříž - Length: 25 m, weight: 30 kg
Denmark
Steno Museet, Aarhus
Odense Technical College, Odense
Geocenter, Faculty of Science, University of Copenhagen - Length 25 m, weight: 145 kg
Estonia
Department of Physics, University of Tartu
Finland
Department of Physics, University of Turku, Turku
Eurajoki - Length: 40 m, weight: 110 kg
Finnish Science Centre Heureka, Vantaa
The watertower of Kuusamo
France
Germany
Jahrtausendturm, Magdeburg
Gymnasium Lünen-Altlünen, Lünen
Gymnasium Verl, Verl
German Museum of Technology, Berlin
University of Bremen
University of Heidelberg
Helmholtz-Gymnasium Heidelberg
Hochschule für Angewandte Wissenschaften Hamburg, Hamburg
School for Business and Technique, Mainz
Deutsches Museum, Munich - Length: 30 m, weight: 30 kg
University of Munich, Geophysics – Department of Earth and Environmental Sciences, 20 m, 12 kg, live webcam, description
Münster, 48 kg, 29 m, with mirrors, Zwei Graue Doppelspiegel für ein Pendel by artist Gerhard Richter in a former church, opened 17 June 2018
University of Osnabrück, Osnabrück, Lower Saxony - Length: 19.5 m, weight: 70 kg
Gymnasium of the city Lennestadt, N |
https://en.wikipedia.org/wiki/Pylephlebitis | Pylephlebitis is an uncommon thrombophlebitis of the portal vein or any of its branches (i.e. a portal vein thrombosis) that is caused by infection. It is usually a complication of intra-abdominal sepsis, most often following diverticulitis, perforated appendicitis, or peritonitis. Considered uniformly lethal in the pre-antibiotic era, it still carries a mortality of 10-30%.
Presentation
It typically presents with fever, rigors, and right upper quadrant abdominal pain, but sometimes abdominal pain may be absent. Liver function test abnormalities are usually present but frank jaundice is uncommon.
Cause
It is a cause of portal hypertension and can cause bowel ischemia sometimes leading to bowel infarction. Diverticulitis (26.5%) and acute appendicitis (22%) are the two most common causes. Pylephlebitis is caused by a single pathogen in 43% of cases and polymicrobial in 27% of cases. The most frequently isolated bacteria are Escherichia coli (25%), Bacteroides spp. (17%), and Streptococcus spp. (15%).
Diagnosis
In the modern era, it is usually diagnosed by CT scans of the abdomen and pelvis. Bacteriology is often polymicrobial and blood cultures are positive in some cases. A significant fraction of people presenting with this condition have an underlying hypercoagulable state.
Treatment
Treatment is with a prolonged course of broad-spectrum antibiotics, with the addition of anticoagulants if other clots are present outside the portal vein or if fever persists on antibiotic therapy. |
https://en.wikipedia.org/wiki/Vizio | Vizio Inc. (stylized VIZIO) is an American publicly traded company that designs and sells televisions, sound bars, viewer data, and advertising. The company was founded in 2002 and is based in Irvine, California.
History
The company was founded in 2002 as V Inc. by entrepreneur William Wang and two founding employees. By 2004, Wang changed the company name to Vizio.
In 2006, the company's revenue was estimated at $700 million, and in 2007 it was estimated to have exceeded $2 billion. Vizio is known for selling its HDTVs at lower prices than its competitors.
On October 19, 2010, Vizio signed a 4-year contract to sponsor U.S. college football's annual Rose Bowl game in Pasadena, California, beginning with the 2011 Rose Bowl and ending with the 2014 Vizio BCS National Championship Game. When the Rose Bowl contract ended, Vizio signed a contract to sponsor the Fiesta Bowl making the official name the Vizio Fiesta Bowl.
In late 2014, Vizio acquired Advanced Media Research Group, Inc., the parent of entertainment website BuddyTV.
On July 24, 2015, Vizio filed with U.S. regulators to raise up to $172.5 million in an initial public offering of Class A common stock; however, the IPO was never completed.
In August 2015, Vizio acquired Cognitive Media Networks, Inc, a provider of automatic content recognition (ACR). Cognitive Media Networks was subsequently renamed Inscape Data. Inscape functioned as an independent entity until the end of 2020, when it was combined with Vizio Ads and SmartCast; the three divisions combining to operate as a single unit.
In November 2015, the U.S. Federal Trade Commission (FTC) and Office of the New Jersey Attorney General brought charges against Vizio, alleging it collected non-personal information on its customers and sold it to advertisers. In February 2017, Vizio agreed to pay $2.2 million to settle the charges. Additionally, the settlement required Vizio to delete the data it had captured and update its data collection practices. Aft |
https://en.wikipedia.org/wiki/Degradation%20%28telecommunications%29 | In telecommunication, degradation is the loss of quality of an electronic signal, which may be categorized as either "graceful" or "catastrophic", and has the following meanings:
The deterioration in quality, level, or standard of performance of a functional unit.
In communications, a condition in which one or more of the required performance parameters fall outside predetermined limits, resulting in a lower quality of service.
There are several forms and causes of degradation in electric signals, both in the time domain and in the physical domain, including runt pulse, voltage spike, jitter, wander, swim, drift, glitch, ringing, crosstalk, antenna effect (not the same antenna effect as in IC manufacturing), and phase noise.
Degradation usually refers to reduction in quality of an analog or digital signal. When a signal is being transmitted or received, it undergoes changes which are undesirable. These changes are called degradation. Degradation is usually caused by: distance, imitation:see Remote Control, noise, interference or EMI.
Digital electronics
Fault tolerance
Noise (electronics)
Telecommunications engineering |
https://en.wikipedia.org/wiki/Self-aligned%20gate | In semiconductor electronics fabrication technology, a self-aligned gate is a transistor manufacturing approach whereby the gate electrode of a MOSFET (metal–oxide–semiconductor field-effect transistor) is used as a mask for the doping of the source and drain regions. This technique ensures that the gate is naturally and precisely aligned to the edges of the source and drain.
The use of self-aligned gates in MOS transistors is one of the key innovations that led to the large increase in computing power in the 1970s. Self-aligned gates are still used in most modern integrated circuit processes.
Introduction
IC construction
Integrated circuits (ICs, or "chips") are produced in a multi-step process that builds up multiple layers on the surface of a disk of silicon known as a "wafer". Each layer is patterned by coating the wafer in photoresist and then exposing it to ultraviolet light being shone through a stencil-like "mask". Depending on the process, the photoresist that was exposed to light either hardens or softens, and in either case, the softer parts are then washed away. The result is a microscopic pattern on the surface of the wafer where a portion of the top layer is exposed while the rest is protected under the remaining photoresist.
The wafer is then exposed to a variety of processes that add or remove materials from the portions of the wafer that are unprotected by the photoresist. In one common process, the wafer is heated to around 1000 C and then exposed to a gas containing a doping material (commonly boron or phosphorus) that changes the electrical properties of the silicon. This allows the silicon to become an electron donor, electron receptor, or near-insulator depending on the type and/or amount of the dopant. In a typical IC this process is used to produce the individual transistors that make up the key elements of an IC.
In the MOSFET, the three parts of a transistor are the source, the drain, and the gate (see diagram). The "field effect" |
https://en.wikipedia.org/wiki/Soluble%20cell%20adhesion%20molecules | Soluble cell adhesion molecules (sCAMs) are a class of
cell adhesion molecule (CAMs - cell surface binding proteins) that may represent important biomarkers for inflammatory processes involving activation or damage to cells such as platelets and the endothelium.
They include soluble isoforms of the cell adhesion molecules ICAM-1, VCAM-1, E-selectin and P-selectin (distinguished as sICAM-1, sVCAM-1, sE-selectin and sP-selectin). The cellular expression of CAMs is difficult to assess clinically, but these soluble forms are present in the circulation and may serve as markers for CAMs.
Research has focused on their role in cardiovascular (particularly atherosclerosis), connective tissue and neoplastic diseases, where blood plasma levels may be a marker of the disease severity or prognosis, and they may be useful in evaluating progress of some treatments.
Many studies have postulated that increased production of cell adhesion molecules (CAMs) on the vascular endothelium (blood vessel lining) plays a role in the development of arterial plaque, with the suggestion from both in vitro and in vivo studies that the CAM production is increased by dyslipidemia (abnormal lipid levels in the blood).
Research studies have used sCAMs as biomarkers to measure correlations with nutrients or nutrient levels as significant, or not.
Reference links
Transmembrane receptors
Signal transduction
Membrane biology
Cell adhesion proteins |
https://en.wikipedia.org/wiki/OpenESB | OpenESB is a Java-based open-source enterprise service bus. It can be used as a platform for both enterprise application integration and service-oriented architecture. OpenESB allows developers to integrate legacy systems, external and internal partners and new development in business processes. It supports a multitude of integration technologies including standard JBI (Java Business Integration), XML with support for XML Schemas, WSDL, and BPEL with the aim of simplicity, efficiency, long-term durability, and low TCO (Total Cost of Ownership).
It used to be owned by Sun Microsystems, but after Oracle and Sun Microsystems merged (see: Sun acquisition by Oracle), the OpenESB Community was created to maintain, improve, promote and support OpenESB.
Architecture
OpenESB consists of 5 parts: the framework, the container, the components, the Integrated Development Environment and the development plugins.
Framework
The framework consists of a lightweight JBI implementation in Java. This implementation is container-agnostic and can work on any platform and any container. Even if development and support are mainly focused on Glassfish V2 and V3 platforms, beta projects on JBoss and standalone JVM work well and are in progress (2012 Q2). In addition to the OpenESB framework being lightweight, it is also reliable and highly scalable. It is embedded in a Java virtual machine and communicates with other framework instances through Binding components. This architecture matches perfectly with new cloud architectures and allows easy deployment and management on very complex infrastructures. The framework is fully manageable with any JMX-based tool such as Jconsole or more sophisticated tools like Opsview or Nagios.
The framework implements a virtual bus known as the Normalised Message Router (NMR). This is a powerful asynchronous intelligent communication channel between components.
Components
The JBI specification defines 2 component types: The services engine (SE) and the |
https://en.wikipedia.org/wiki/Hydrosilylation | Hydrosilylation, also called catalytic hydrosilation, describes the addition of Si-H bonds across unsaturated bonds. Ordinarily the reaction is conducted catalytically and usually the substrates are unsaturated organic compounds. Alkenes and alkynes give alkyl and vinyl silanes; aldehydes and ketones give silyl ethers. Hydrosilylation has been called the "most important application of platinum in homogeneous catalysis."
Scope and mechanism
Hydrosilylation of alkenes represents a commercially important method for preparing organosilicon compounds. The process is mechanistically similar to the hydrogenation of alkenes. In fact, similar catalysts are sometimes employed for the two catalytic processes.
The prevalent mechanism, called the Chalk-Harrod mechanism, assumes an intermediate metal complex that contains a hydride, a silyl ligand (R3Si), and the alkene substrate. Oxidative addition proceeds by the intermediacy of a sigma-complex, wherein the Si-H bond is not fully broken.
Hydrosilylation of alkenes usually proceeds via anti-Markovnikov addition, i.e., silicon is placed at the terminal carbon when hydrosilylating a terminal alkene Variations of the Chalk-Harrod mechanism exist. Some cases involve insertion of alkene into M-Si bond followed by reductive elimination, the opposite of the sequence in the Chalk-Harrod mechanism. In certain cases, hydrosilylation results in vinyl or allylic silanes resulting from beta-hydride elimination.
Alkynes also undergo hydrosilylation, e.g., the addition of triethylsilane to diphenylacetylene:
Et3SiH + PhC≡CPh → Et3Si(Ph)C=CH(Ph)
Asymmetric hydrosilylation
Using chiral phosphines as spectator ligands, catalysts have been developed for catalytic asymmetric hydrosilation. A well studied reaction is the addition of trichlorosilane to styrene to give 1-phenyl-1-(trichlorosilyl)ethane:
Cl3SiH + PhCH=CH2 → (Ph)(CH3)CHSiCl3
Nearly perfect enantioselectivities (ee's) can be achieved using palladium catalysts supported b |
https://en.wikipedia.org/wiki/Exchange%20matrix | In mathematics, especially linear algebra, the exchange matrices (also called the reversal matrix, backward identity, or standard involutory permutation) are special cases of permutation matrices, where the 1 elements reside on the antidiagonal and all other elements are zero. In other words, they are 'row-reversed' or 'column-reversed' versions of the identity matrix.
Definition
If J is an n × n exchange matrix, then the elements of J are
Properties
Premultiplying a matrix by an exchange matrix flips vertically the positions of the former's rows, i.e.,
Postmultiplying a matrix by an exchange matrix flips horizontally the positions of the former's columns, i.e.,
Exchange matrices are symmetric; that is, JnT = Jn.
For any integer k, Jnk = I if k is even and Jnk = Jn if k is odd. In particular, Jn is an involutory matrix; that is, Jn−1 = Jn.
The trace of Jn is 1 if n is odd and 0 if n is even. In other words, the trace of Jn equals .
The determinant of Jn equals . As a function of n, it has period 4, giving 1, 1, −1, −1 when n is congruent modulo 4 to 0, 1, 2, and 3 respectively.
The characteristic polynomial of Jn is when n is even, and when n is odd.
The adjugate matrix of Jn is .
Relationships
An exchange matrix is the simplest anti-diagonal matrix.
Any matrix A satisfying the condition AJ = JA is said to be centrosymmetric.
Any matrix A satisfying the condition AJ = JAT is said to be persymmetric.
Symmetric matrices A that satisfy the condition AJ = JA are called bisymmetric matrices. Bisymmetric matrices are both centrosymmetric and persymmetric.
See also
Pauli matrices (the first Pauli matrix is a 2 × 2 exchange matrix) |
https://en.wikipedia.org/wiki/Yamartino%20method | The Yamartino method is an algorithm for calculating an approximation of the circular variance of wind direction during a single pass through the incoming data.
Background
The simple method for calculating circular variance requires two passes through the list of values. The first pass determines the circular mean of those values, while the second pass determines the variance. This double-pass method requires access to all values.
There is also a single-pass method for calculating the standard deviation, but this method is unsuitable for angular data such as wind direction. Trying to calculate angular moments by naively applying the standard formulas to angular expressions yields absurd results. For example, a dataset that measures wind speeds of 1° and 359° would average to 180°, but expressing the same data as 1° and -1° (equal to 359°) would give an average of 0°. Thus, we define circular moments by placing all measured angles on a unit circle, then calculating the moments of these points.
The Yamartino method, introduced by Robert J. Yamartino in 1984, solves both problems
A further discussion of the Yamartino method, along with other methods of estimating the standard deviation of wind direction can be found in Farrugia & Micallef.
It is possible to calculate the exact standard deviation in one pass. However, that method needs slightly more calculation effort.
Algorithm
Over the time interval to be averaged across, n measurements of wind direction (θ) will be made and two totals are accumulated without storage of the n individual values. At the end of the interval the calculations are as follows: with the average values of sin θ and cos θ defined as
Then the average wind direction is given via the four-quadrant arctan(x,y) function as
From twenty different functions for σθ using variables obtained in a single-pass of the wind direction data, Yamartino found the best function to be
where
The key here is to remember that sin2θ + cos2θ = 1 so that for |
https://en.wikipedia.org/wiki/Andrica%27s%20conjecture | Andrica's conjecture (named after Dorin Andrica) is a conjecture regarding the gaps between prime numbers.
The conjecture states that the inequality
holds for all , where is the nth prime number. If denotes the nth prime gap, then Andrica's conjecture can also be rewritten as
Empirical evidence
Imran Ghory has used data on the largest prime gaps to confirm the conjecture for up to 1.3002 × 1016. Using a table of maximal gaps and the above gap inequality, the confirmation value can be extended exhaustively to 4 × 1018.
The discrete function is plotted in the figures opposite. The high-water marks for occur for n = 1, 2, and 4, with A4 ≈ 0.670873..., with no larger value among the first 105 primes. Since the Andrica function decreases asymptotically as n increases, a prime gap of ever increasing size is needed to make the difference large as n becomes large. It therefore seems highly likely the conjecture is true, although this has not yet been proven.
Generalizations
As a generalization of Andrica's conjecture, the following equation has been considered:
where is the nth prime and x can be any positive number.
The largest possible solution for x is easily seen to occur for n=1, when xmax = 1. The smallest solution for x is conjectured to be xmin ≈ 0.567148... which occurs for n = 30.
This conjecture has also been stated as an inequality, the generalized Andrica conjecture:
for
See also
Cramér's conjecture
Legendre's conjecture
Firoozbakht's conjecture |
https://en.wikipedia.org/wiki/Lucas%27s%20theorem | In number theory, Lucas's theorem expresses the remainder of division of the binomial coefficient by a prime number p in terms of the base p expansions of the integers m and n.
Lucas's theorem first appeared in 1878 in papers by Édouard Lucas.
Statement
For non-negative integers m and n and a prime p, the following congruence relation holds:
where
and
are the base p expansions of m and n respectively. This uses the convention that if m < n.
Proofs
There are several ways to prove Lucas's theorem.
Consequences
A binomial coefficient is divisible by a prime p if and only if at least one of the base p digits of n is greater than the corresponding digit of m.
In particular, is odd if and only if the binary digits (bits) in the binary expansion of n are a subset of the bits of m.
Variations and generalizations
Kummer's theorem asserts that the largest integer k such that pk divides the binomial coefficient (or in other words, the valuation of the binomial coefficient with respect to the prime p) is equal to the number of carries that occur when n and m − n are added in the base p.
Generalizations of Lucas's theorem to the case of p being a prime power are given by Davis and Webb (1990) and Granville (1997).
The q-Lucas theorem is a generalization for the q-binomial coefficients, first proved by J. Désarménien. |
https://en.wikipedia.org/wiki/Vacuum%20cementing | Vacuum cementing or vacuum welding is the natural process of solidifying small objects in a hard vacuum. The most notable example is dust on the surface of the Moon.
This effect was reported to be a problem with the first American and Soviet satellites, as small moving parts would seize together.
In 2009 the European Space Agency published a peer-reviewed paper detailing why cold welding is a significant issue that spacecraft designers need to carefully consider. The conclusions of this appropriately titled study can be found on page 25 of "Assessment of Cold Welding Between Separable Contact Surfaces due to Impact and Fretting Under Vacuum". The paper also cites a documented example from 1991 with the Galileo spacecraft high-gain antenna (see page 2; the technical source document from NASA regarding the Galileo spacecraft is also provided in a link here).
One source of difficulty is that vacuum (AKA cold) welding does not exclude relative motion between the surfaces that are to be joined. This allows the broadly defined notions of galling, fretting, sticking, stiction and adhesion to overlap in some instances. For example, it is possible for a joint to be the result of both vacuum welding and galling (and/or fretting and/or impact). Galling and vacuum welding, therefore, are not mutually exclusive.
See also |
https://en.wikipedia.org/wiki/Major%20duodenal%20papilla | The major duodenal papilla (papilla of Vater) is a rounded projection in the duodenum into which the common bile duct and pancreatic duct drain. The major duodenal papilla is, in most people, the primary mechanism for the secretion of bile and other enzymes that facilitate digestion.
Structure
The major duodenal papilla is situated in the second part of the duodenum, 7–10 cm from the pylorus, at the level of the second or third lumbar vertebrae. It is surrounded by the sphincter of Oddi, a circular muscle, and receives a mixture of pancreatic enzymes and bile from the Ampulla of Vater, which drains both the pancreatic duct and biliary system. The junction between the foregut and midgut occurs directly below the major duodenal papilla. The major duodenal papilla projects less than a centimetre into the lumen of the duodenum. It appears rounded and is often covered by a fold on the uppermost side of the papilla; that is, the side which receives contents from the stomach.
The major duodenal papilla is seen from the duodenum as lying within a mucosal fold. The minor duodenal papilla is situated 2 cm proximal.
Variation
The major duodenal papilla is occasionally found in the junction between the descending and horizontal parts of the duodenum, or in the horizontal part of the duodenum; a case study of 1000 people demonstrated this in 12 and 8% respectively. in the third part of the duodenum, the level of the vertebrae may be L2-3, and in about 10% of people, it may not receive bile. Additionally, in a small number of people, the primary papilla for draining the pancreas may in fact be the accessory pancreatic duct.
Function
Pancreatic enzymes and bile drain into the duodenum from both the pancreatic duct and biliary system. This facilitates the digestion of food; particularly proteins (pancreatic enzymes), and fat-soluble vitamins (bile).
Clinical significance
The minor papilla drains the duct of Santorini, superior in position to the major papilla. In pancreati |
https://en.wikipedia.org/wiki/Marcus%20Fenix | Marcus Michael Fenix is a fictional character and the primary protagonist from the first three games in the Gears of War video game series. He first appeared in the first game of the series, released in 2006.
Appearances
Video games
Fenix debuted as the protagonist of Gears of War in 2006. Fenix is a convict who is reinstated into the Coalition of Ordered Governments' (COG) military to assist a last-ditch mission to destroy the Locust Horde. Fenix led a famed military career in the COG's previous conflicts, but was arrested after leading a failed unauthorized mission to rescue his father, Adam. Fenix joins his close friend, Dom Santiago, in Delta Squad as they succeed in helping the COG military deploy a missile strike against the Locust Horde.
Fenix retains his role throughout the trilogy, where he plays a pivotal role in humanity's conflict against the Locust Horde. He cripples the Locust Horde in Gears of War 2 by flooding their subterranean civilization. In Gears of War 3, Fenix discovers his father is alive and has developed a weapon that will destroy the Locust Horde and a new threat, the Lambent. Adam releases his weapon but dies in the process. While successful in vanquishing humanity's enemies, Fenix is distraught over the death of his loved ones and comrades, including Dom and his father. He is consoled by Anya Stroud, one of his closest allies and love interest, who assures him their sacrifices have given humanity a new hope.
Fenix transitions into the role of a supporting character in 2016's Gears of War 4, set 25 years after the events of Gears of War 3. Fenix has fathered a now adult son with Anya, James Dominic "JD" Fenix, who serves as the game's protagonist. In Gears 5, Fenix returns to active service with COG to fight a new foe, the Swarm. During a heated exchange between Marcus and COG First Minister Mina Jinn, it is revealed that Anya had passed away at some point during the 25-year antebellum period due to unspecified birthing complication i |
https://en.wikipedia.org/wiki/WRME-LD | WRME-LD (channel 33) is a low-power television station in Chicago, Illinois, United States, affiliated with Jewelry Television. The station's audio channel, transmitting at 87.75 MHz (or VHF channel 6), lies within the FM band; as a result, WRME-LD's audio channel operates as a radio station at 87.7 FM. Owned by Venture Technologies Group and operated under a local marketing agreement (LMA) by Weigel Broadcasting, the station airs a soft adult contemporary/oldies format via the 87.75 MHz audio channel under the brand 87.7 MeTV FM, a brand extension of Weigel's MeTV television network. The WRME-LD studios are co-located with Weigel's headquarters in Chicago's Greektown neighborhood, while the transmitter resides atop the John Hancock Center.
Because of the station's low-power status, WRME-LD is not subject to the FCC's educational and informational programming requirements, allowing a full 24/7 format without interruption for other programming. In November 2019, the station (as WRME-LP) began airing news and weather updates from WBBM-TV (channel 2) during the morning and afternoon drive times.
After the 2009 digital television transition for full-power stations, WRME-LP became one of several such "Franken-FM" stations that were actually analog TV stations on channel 6; the video signal aired unrelated material to the audio, including a loop of weather and traffic information. When low-power stations were required to transition to digital, Venture Technologies Group obtained special temporary authority to convert the station to ATSC 3.0 Next Gen TV and also maintain an analog audio signal on 87.7 FM. The ATSC 3.0 channel occupies the lower 5.509 MHz of the 6 MHz channel.
Officially, the second HD Radio channel of Audacy-owned WMYX-FM in Milwaukee, Wisconsin is a repeater of WRME-LD's audio signal, and both stations identify together as "WRME-LD, Chicago and WMYX-FM-HD2, Milwaukee". The WMYX-HD2 signal also carried by the Audacy app, which is available throughout th |
https://en.wikipedia.org/wiki/Arterial%20arcades | The arterial arcades (intermesenteric arterial anastomoses or Riolan arcades) are a series of anastomosing arterial arches between the arterial branches of the jejunum and ileum.
Nearest the duodenum the mesenteric loops are primary, the vasa recta are long and regular in distribution, and the translucent spaces (lunettes) are extensive.
Toward the ileocolic junction, secondary and tertiary loops are observed, the vessels are smaller and become obscured by numerous fat-tabs.
The diagrams below show the arrangement and variations of the loops of the mesenteric vessels for various segments of the small intestine of average length:
Additional images
See also
Intestinal arteries |
https://en.wikipedia.org/wiki/Herbert%20E.%20Ives | Herbert Eugene Ives (July 31, 1882 – November 13, 1953) was a scientist and engineer who headed the development of facsimile and television systems at AT&T in the first half of the twentieth century. He is best known for the 1938 Ives–Stilwell experiment, which provided direct confirmation of special relativity's time dilation, although Ives himself did not accept special relativity, and argued instead for an alternative interpretation of the experimental results. Ives has been described as "the most authoritative opponent of relativity in United States between the late 1930s and the early 1950s."
Biography
Ives was born on July 31, 1882, in Philadelphia, Pennsylvania, to Frederic Eugene Ives and Mary Olmstead. He studied at the University of Pennsylvania and the Johns Hopkins University, where he graduated in 1908. He married Mabel Lorenz in the same year and they had three children.
He wrote a 1920 book on aerial photography while an Army reserve officer in the aviation section. He was president of the Optical Society of America (now Optica) from 1924 to 1925. At the Bell Labs he became its Director of Electro-Optical Research.
Like his father Frederic E. Ives, Herbert was an expert on color photography. In 1924, he transmitted and reconstructed the first color fax, a natural-color photograph of silent film star Rudolph Valentino in period costume, using red, green and blue color separations he photographed on the set of Valentino's film Monsieur Beaucaire.
On April 7, 1927, Ives demonstrated 185-line long-distance television, transmitting live video images of then-Secretary of Commerce Herbert Hoover via AT&T's experimental station 3XN in Whippany, New Jersey, allowing media reporters to both see and communicate with Hoover. By 1930, his two-way television-telephone system (called an ikonophoneGreek: 'image-sound' ) was in regular experimental use. Bell Labs' large New York City research facility devoted years of research and development through the 1930s, |
https://en.wikipedia.org/wiki/Couple%20%28mechanics%29 | In mechanics, a couple is a system of forces with a resultant (a.k.a. net or sum) moment of force but no resultant force.
A more descriptive term is force couple or pure moment. Its effect is to impart angular momentum but no linear momentum. In rigid body dynamics, force couples are free vectors, meaning their effects on a body are independent of the point of application.
The resultant moment of a couple is a special case of moment. A couple has the property that it is independent of reference point.
Simple couple
Definition
A couple is a pair of forces, equal in magnitude, oppositely directed, and displaced by perpendicular distance or moment.
The simplest kind of couple consists of two equal and opposite forces whose lines of action do not coincide. This is called a "simple couple". The forces have a turning effect or moment called a torque about an axis which is normal (perpendicular) to the plane of the forces. The SI unit for the torque of the couple is newton metre.
If the two forces are and , then the magnitude of the torque is given by the following formula:
where
is the moment of couple
is the magnitude of the force
is the perpendicular distance (moment) between the two parallel forces
The magnitude of the torque is equal to , with the direction of the torque given by the unit vector , which is perpendicular to the plane containing the two forces and positive being a counter-clockwise couple. When is taken as a vector between the points of action of the forces, then the torque is the cross product of and , i.e.
Independence of reference point
The moment of a force is only defined with respect to a certain point (it is said to be the "moment about ") and, in general, when is changed, the moment changes. However, the moment (torque) of a couple is independent of the reference point : Any point will give the same moment. In other words, a couple, unlike any more general moments, is a "free vector". (This fact is called Varignon's Second Mom |
https://en.wikipedia.org/wiki/Metzler%20matrix | In mathematics, a Metzler matrix is a matrix in which all the off-diagonal components are nonnegative (equal to or greater than zero):
It is named after the American economist Lloyd Metzler.
Metzler matrices appear in stability analysis of time delayed differential equations and positive linear dynamical systems. Their properties can be derived by applying the properties of nonnegative matrices to matrices of the form M + aI, where M is a Metzler matrix.
Definition and terminology
In mathematics, especially linear algebra, a matrix is called Metzler, quasipositive (or quasi-positive) or essentially nonnegative if all of its elements are non-negative except for those on the main diagonal, which are unconstrained. That is, a Metzler matrix is any matrix A which satisfies
Metzler matrices are also sometimes referred to as -matrices, as a Z-matrix is equivalent to a negated quasipositive matrix.
Properties
The exponential of a Metzler (or quasipositive) matrix is a nonnegative matrix because of the corresponding property for the exponential of a nonnegative matrix. This is natural, once one observes that the generator matrices of continuous-time Markov chains are always Metzler matrices, and that probability distributions are always non-negative.
A Metzler matrix has an eigenvector in the nonnegative orthant because of the corresponding property for nonnegative matrices.
Relevant theorems
Perron–Frobenius theorem
See also
Nonnegative matrices
Delay differential equation
M-matrix
P-matrix
Q-matrix, a specific kind of Metzler matrix
Z-matrix
Hurwitz matrix
Stochastic matrix
Positive systems
Bibliography
Matrices |
https://en.wikipedia.org/wiki/Signature%20matrix | In mathematics, a signature matrix is a diagonal matrix whose diagonal elements are plus or minus 1, that is, any matrix of the form:
Any such matrix is its own inverse, hence is an involutory matrix. It is consequently a square root of the identity matrix. Note however that not all square roots of the identity are signature matrices.
Noting that signature matrices are both symmetric and involutory, they are thus orthogonal. Consequently, any linear transformation corresponding to a signature matrix constitutes an isometry.
Geometrically, signature matrices represent a reflection in each of the axes corresponding to the negated rows or columns.
Properties
If A is a matrix of N*N then:
(Due to the diagonal values being -1 or 1)
The Determinant of A is either 1 or -1 (Due to it being diagonal)
See also
Metric signature |
https://en.wikipedia.org/wiki/Food%20chemistry | Food chemistry is the study of chemical processes and interactions of all biological and non-biological components of foods. The biological substances include such items as meat, poultry, lettuce, beer, milk as examples. It is similar to biochemistry in its main components such as carbohydrates, lipids, and protein, but it also includes areas such as water, vitamins, minerals, enzymes, food additives, flavors, and colors. This discipline also encompasses how products change under certain food processing techniques and ways either to enhance or to prevent them from happening. An example of enhancing a process would be to encourage fermentation of dairy products with microorganisms that convert lactose to lactic acid; an example of preventing a process would be stopping the browning on the surface of freshly cut apples using lemon juice or other acidulated water.
History of food chemistry
The scientific approach to food and nutrition arose with attention to agricultural chemistry in the works of J. G. Wallerius, Humphry Davy, and others. For example, Davy published Elements of Agricultural Chemistry, in a Course of Lectures for the Board of Agriculture (1813) in the United Kingdom which would serve as a foundation for the profession worldwide, going into a fifth edition. Earlier work included that by Carl Wilhelm Scheele, who isolated malic acid from apples in 1785.
Some of the findings of Liebig on food chemistry were translated and published by Eben Horsford in Lowell Massachusetts in 1848.
In 1874 the Society of Public Analysts was formed, with the aim of applying analytical methods to the benefit of the public. Its early experiments were based on bread, milk, and wine.
It was also out of concern for the quality of the food supply, mainly food adulteration and contamination issues that would first stem from intentional contamination to later with chemical food additives by the 1950s. The development of colleges and universities worldwide, most notably in the Un |
https://en.wikipedia.org/wiki/Greg%20Sams | Gregory Sams (born 1948 in Los Angeles, California) is a UK-based, American-born, fractal artist, author and publisher.
Life and works
Greg has been a wheelchair user since falling from a tree whilst a freshman at the University of California, Berkeley.
Greg moved to London and, aged 19, then subsequently opened SEED, a macrobiotic restaurant in Paddington with his brother Craig Sams in 1968.
SEED Restaurant soon became popular with the 1960s London psychedelic scene, and was frequented by John Lennon among others, who drew a cartoon about his experiences at SEED.
The Sams brothers opened a specialised macrobiotic foodshop, Ceres Grain, the following year. To spread the word about Ceres and SEED, Greg published three editions of a specialised magazine called 'Harmony'. During the 1970s, Greg, his brother Craig and their father Ken edited and published a magazine called 'Seed, the Journal of Organic Living' over a seven-year period.
In 1970 Greg and Craig set up Harmony Foods, which eventually became known as Whole Earth Foods.
In 1982, Greg left Whole Earth Foods with his brother who went on to become chairperson of the Soil Association, and develop Green & Blacks organic chocolate with his partner.
In 1990, Sams opened Strange Attractions in London, the only shop in the world dedicated to chaos theory. He became known for his fractal art, his designs adorning postcards, t-shirts and textiles all over the world.
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An enthusiast of the counterculture movement, such as the non-violent direct action street reclaiming events in the UK and elsewhere such as Reclaim the Streets, Sams began writing books that were promoted at these events, as well as during various trance music, psytrance and acid techno raves and free parties around the UK. Uncommon Sense - the State is Out of Date was published in 1998 in which he put forward his views on the importance of chaos theory in the way we live - and should live - our lives. In 2006 he completed a new book, Sun of gOd |
https://en.wikipedia.org/wiki/Epipolar%20geometry | Epipolar geometry is the geometry of stereo vision. When two cameras view a 3D scene from two distinct positions, there are a number of geometric relations between the 3D points and their projections onto the 2D images that lead to constraints between the image points. These relations are derived based on the assumption that the cameras can be approximated by the pinhole camera model.
Definitions
The figure below depicts two pinhole cameras looking at point X. In real cameras, the image plane is actually behind the focal center, and produces an image that is symmetric about the focal center of the lens. Here, however, the problem is simplified by placing a virtual image plane in front of the focal center i.e. optical center of each camera lens to produce an image not transformed by the symmetry. OL and OR represent the centers of symmetry of the two cameras lenses. X represents the point of interest in both cameras. Points xL and xR are the projections of point X onto the image planes.
Each camera captures a 2D image of the 3D world. This conversion from 3D to 2D is referred to as a perspective projection and is described by the pinhole camera model. It is common to model this projection operation by rays that emanate from the camera, passing through its focal center. Each emanating ray corresponds to a single point in the image.
Epipole or epipolar point
Since the optical centers of the cameras lenses are distinct, each center projects onto a distinct point into the other camera's image plane. These two image points, denoted by eL and eR, are called epipoles or epipolar points. Both epipoles eL and eR in their respective image planes and both optical centers OL and OR lie on a single 3D line.
Epipolar line
The line OL–X is seen by the left camera as a point because it is directly in line with that camera's lens optical center. However, the right camera sees this line as a line in its image plane. That line (eR–xR) in the right camera is called an |
https://en.wikipedia.org/wiki/Kodak%20Photo%20Spot | A Kodak Photo Spot (also called Kodak Picture Spot or Kodak Photo Point) is a location with a Kodak-sponsored sign indicating a recommended spot from which to take a photograph. They are found in areas popular with tourists, and are particularly common in Disney theme parks. This was until 2012, when the Kodak company filed for bankruptcy, and ended their sponsorship as the camera and film supplier for Disney Parks. In 2013, Nikon became the official sponsor of camera supplies in Disney Parks in the US, and the Kodak Photo Spots were re-branded as Nikon Photo Spots.
One such sign reads, "This location recommended by top photographers to help you tell the story of your visit in pictures."
In a project for the Center for Land Use Interpretation, artists Melinda Stone and Igor Vamos installed "Suggested Photo Spots" signs at various locations across the United States; one of their spots included the wastewater treatment facility for Eastman Kodak's headquarters. |
https://en.wikipedia.org/wiki/Hans%20Camenzind | Hans R. Camenzind (; 1 January 1934 – 8 August 2012) was an electronics engineer known for designing the 555 timer IC in 1971 under contract to Signetics. He was the inventor on 20 US patents. Camenzind also wrote three books and numerous technical articles, and lectured at the University of Santa Clara.
Background and education
Camenzind was born and raised in Zürich, Switzerland, where he went to college. In 1960 he moved to the United States, first receiving an MSEE from Northeastern University and then an MBA from the University of Santa Clara. Camenzind taught circuit design in the morning, then attending classes at the same university at night working towards a Master's degree in Business Administration.
Career
In 1962, Camenzind joined the Laboratory for Physical Science at P.R. Mallory in Burlington, Massachusetts. After six years of research, Camenzind moved to California in 1968 to join Signetics, but two years later he felt Signetics "lost its way" and resigned to write a book. He told them he didn't want to come back, and wanted to work as a consultant and independent designer, he proposed the 555 design in 1971. He then started Interdesign, a semiconductor design company, which he headed for seven years before selling out to Ferranti. Following the sale of Interdesign, Camenzind became an independent analog IC design consultant.
During his career Camenzind designed the first integrated class D amplifier, introduced the IC phase-locked loop, invented the semicustom IC, and created the legendary 555 timer. By 2006, he had designed 140 standard and custom ICs, such as:
Signetics LM555
Signetics LM565
Signetics LM566
Signetics LM567
Zetex Semiconductors ZSCT1555
Books
Camenzind wrote three books and numerous technical articles. His last book, Much Ado About Almost Nothing, published in February 2007, is a general audience book about the history of electronics. Other books include, Designing Analog Chips and, under the pen name John Penter, he |
https://en.wikipedia.org/wiki/Twin-arginine%20translocation%20pathway | The twin-arginine translocation pathway (Tat pathway) is a protein export, or secretion pathway found in plants, bacteria, and archaea. In contrast to the Sec pathway which transports proteins in an unfolded manner, the Tat pathway serves to actively translocate folded proteins across a lipid membrane bilayer. In plants, the Tat translocase is located in the thylakoid membrane of the chloroplast, where it acts to export proteins into the thylakoid lumen. In bacteria, the Tat translocase is found in the cytoplasmic membrane and serves to export proteins to the cell envelope, or to the extracellular space. The existence of a Tat translocase in plant mitochondria is also proposed.
In the plant thylakoid membrane and in Gram-negative bacteria the Tat translocase is composed of three essential membrane proteins; TatA, TatB, and TatC. In the most widely studied Tat pathway, that of the Gram-negative bacterium Escherichia coli, these three proteins are expressed from an operon with a fourth Tat protein, TatD, which is not required for Tat function. A fifth Tat protein TatE that is homologous to the TatA protein is present at a much lower level in the cell than TatA and is not believed to play any significant role in Tat function.
The Tat pathways of Gram-positive bacteria differ in that they do not have a TatB component. In these bacteria the Tat system is made up from a single TatA and TatC component, with the TatA protein being bifunctional and fulfilling the roles of both E. coli TatA and TatB.
The name of the Tat pathway relates to a highly conserved twin-arginine leader motif (S/TRRXFLK) which is found in the N terminal Signal peptide of the corresponding passenger proteins. The signal peptide is removed by a signal peptidase after release of the transported protein from the Tat complex. At least two TatC molecules co-exist within each Tat translocon.
In pathogens
Not all bacteria carry the tatABC genes in their genome; however, of those that do, there seems to be |
https://en.wikipedia.org/wiki/Sorcerian | is a 1987 action role-playing game developed by Nihon Falcom as the fifth installment in the Dragon Slayer line of games. Originally released for the PC-8801 Personal Computer, it has since been released on a wide variety of platforms.
Gameplay
Sorcerian is a side-scrolling action-RPG. The player can create up to ten characters, from whom up to four members can be present in a party at the same time. Each character is highly customizable, with four different classes/races (fighter, wizard, elf, and dwarf) and over 60 possible jobs/occupations (ranging from clown to exorcist) available for them to perform; each has its own strengths and weaknesses, affecting the seven primary attributes (strength, intelligence, protection, magic resistance, vitality, dexterity, and karma) in different ways, as well as different equipment limitations.
The player can choose from fifteen different scenarios, or quests, to play through in the order of their choice. The party must battle enemies and perform tasks within the given levels to clear each scenario, before moving onto another scenario of their choice. The player controls the entire party at the same time, with all four members running in a line, jumping in sequence, and attacking in unison. The party members follow behind in a manner similar to the Options in the arcade shooter Gradius (1985). Sorcerian also employs class-based puzzles, such as using a high-strength character to force open doors.
All the characters have a default starting age of 16. Each time a player begins a new scenario, a year passes by, while additional time passes by in towns as a character goes through training or enchants items. The characters age at different rates depending on their race, with humans reaching old age at 60, dwarves at 100, and elves at 200. Upon reaching old age, for every year that passes, a character can die permanently at a random time. There is also an "Advance Time" to speed up the flow of time. Another new feature of Sorceria |
https://en.wikipedia.org/wiki/Cocky%20%28mascot%29 | Cocky is the costumed mascot of the University of South Carolina athletics teams. He represents a cartoon version of a gamecock (a fighting rooster).
Although the Gamecock has been the University of South Carolina's official symbol since 1902, there was no official mascot until 1971. Instead, during the early years, fans would dress up in their own costumes during the games. Beginning in 1971, John Nelson, an undergraduate biology student, attended games in a Gamecock costume. This mascot was known as "The Rooster". The costume included fabric feathers, a cardboard bill, and Styrofoam spurs, and was made by his mother. The Rooster attended both basketball and football games. "The Rooster" costume can be seen at USC's McKissick Museum.
Dr. John Nelson can still be found at USC. He is currently the Curator of the University of South Carolina Herbarium, and plans to retire in 2018.
The current version of Cocky made his debut, by Robert Lane, at the Homecoming game of 1980 against Cincinnati. He was portrayed as the son of Big Spur, a large, gangly barn yard rooster that had been attending games since 1978 as a mascot of the university.
Big Spur had been introduced as a fraternity pledge class project headed by student Chuck Eaton. Eaton served as the mascot from 1978 until 1980 when the role was taken over by USC students Robert Lane and John Routh. Big Spur was seen as too large and unwieldy with limited mobility.
Therefore, Cocky, Big Spur's "son", was brought in to replace Big Spur. When introduced, Cocky was originally booed off the field by students and fans who thought he was not "dignified enough". After this inauspicious beginning, the South Carolina Athletic Department determined Lane would wear the "Big Spur" costume for the remainder of the school year and John Routh would take over as "Cocky" in hopes that alumni would warm to the new mascot. Routh is credited with making "Cocky" a sensation- both at the University and nationally. A few years la |
https://en.wikipedia.org/wiki/List%20of%20flags%20by%20color%20combination | This is a list of flags of states, territories, former, and other geographic entities (plus a few non-geographic flags) sorted by their combinations of dominant colors. Flags emblazoned with seals, coats of arms, and other multicolored emblems are sorted only by their color fields. The color of text is almost entirely ignored.
Colors related to the two metals of European heraldry (gold and white) are sorted first. The five major colors of European heraldry (black, red, blue, green, and purple) are sorted next. Miscellaneous colors (murrey, tan, grey, and pink) are sorted last.
Similar colors are grouped together to make navigation of this list practical. As such, the dark greens prevalent in the Middle East are sorted together with the brighter greens prevalent in Western Europe. Significantly, yellows, golds, and oranges are grouped together as "gold" due to the lack of discrete divisions within this spectrum and the differing standards of interpretation of "gold", which appears in the legally codified specifications of many flags. Some flags, including a number from South Asia, include both a distinct yellow and a distinct orange; these have been noted accordingly. Magenta is included with red.
Gold
, United States (with multicolored seal)
(1632–1946)
, Poland (with multicolored coat of arms)
, United States (with multicolored coat of arms)
Gold, white
(1527–1813)
(with distinct yellow and orange)
(1837–1866)
(with distinct orange)
, United States (with a distinct gold and orange and a brown emblem)
– flag used by several Crusader states
, Poland (with multicolored coat of arms)
(1250–1517)
, Japan
, Guatemala
, California, United States (with multicolored emblem)
, Indonesia
(with multicolored emblem)
Gold, white, black
, Maryland, United States
(1906–1959)
, Poland
, England, United Kingdom
, Malaysia
(1858–1883), House of Romanov
, Scotland, United Kingdom
, Poland
Gold, white, black, red
, England, United Kingdom
, Belgium
, Switzerland
, |
https://en.wikipedia.org/wiki/Stanley%E2%80%93Wilf%20conjecture | The Stanley–Wilf conjecture, formulated independently by Richard P. Stanley and Herbert Wilf in the late 1980s, states that the growth rate of every proper permutation class is singly exponential. It was proved by and is no longer a conjecture. Marcus and Tardos actually proved a different conjecture, due to , which had been shown to imply the Stanley–Wilf conjecture by .
Statement
The Stanley–Wilf conjecture states that for every permutation β, there is a constant C such that the number |Sn(β)| of permutations of length n which avoid β as a permutation pattern is at most Cn. As observed, this is equivalent to the convergence of the limit
The upper bound given by Marcus and Tardos for C is exponential in the length of β. A stronger conjecture of had stated that one could take C to be , where k denotes the length of β, but this conjecture was disproved for the permutation by . Indeed, has shown that C is, in fact, exponential in k for almost all permutations.
Allowable growth rates
The growth rate (or Stanley–Wilf limit) of a permutation class is defined as
where an denotes the number of permutations of length n in the class. Clearly not every positive real number can be a growth rate of a permutation class, regardless of whether it is defined by a single forbidden pattern or a set of forbidden patterns. For example, numbers strictly between 0 and 1 cannot be growth rates of permutation classes.
proved that if the number of permutations in a class of length n is ever less than the nth Fibonacci number then the enumeration of the class is eventually polynomial. Therefore, numbers strictly between 1 and the golden ratio also cannot be growth rates of permutation classes. Kaiser and Klazar went on to establish every possible growth constant of a permutation class below 2; these are the largest real roots of the polynomials
for an integer k ≥ 2. This shows that 2 is the least accumulation point of growth rates of permutation classes.
later extended the ch |
https://en.wikipedia.org/wiki/Tendinous%20intersection | The rectus abdominis muscle is crossed by three fibrous bands called the tendinous intersections or tendinous inscriptions. One is usually situated at the level of the umbilicus, one at the extremity of the xiphoid process, and the third about midway between the two.
These intersections pass transversely or obliquely across the muscle; they rarely extend completely through its substance and may pass only halfway across it; they are intimately adherent in front to the sheath of the muscle.
Sometimes one or two additional intersections, generally incomplete, are present below the umbilicus.
Colloquial reference
If well-defined, the rectus abdominis is colloquially called a "six-pack". This is due to tendinous intersections within the muscle, usually at the level of the umbilicus (belly-button), the xiphisternum, and about halfway between.
An extremely well defined abdominal section can appear to be an "eight pack", as all eight sections of the abdominal muscle become defined. This definition is prominent among athletes with low body fat percentages, such as bodybuilders, boxers, mixed martial artists, rock climbers, and track and field athletes.
Physiological function
The tendinous intersections, in conjunction with the rectus abdominis, function to provide varying degrees of forward flexion to the lumbar region of the vertebral column, producing forward bending at the waist. Forward flexion results in a decreased angle between the trunk and lower body.
The anatomical segmentation of the rectus abdominis into three pairs of muscles and the positioning of these three pairs of muscles at different levels along the lumbar region (which are created by the tendinous intersections) are responsible for the forward flexion of the vertebral column:
As the superior (or proximal) pair of rectus abdominis muscles contract, the vertebral column is able to slightly flex forward.
If more forward flexion is needed, the middle pair of rectus abdominis muscles can contract alon |
https://en.wikipedia.org/wiki/Auramine%20phenol%20stain | Auramine phenol stain is a stain used in clinical microbiology and histology to identify tuberculosis mycobacteria.
There are two types of auramine phenol stains, 1 and 2 to stain mycobacterium species and cryptosporidium respectively. Both are fluorescent stains. The bacteria or the parasites appear brilliant greenish yellow against dark background.
Mycolic acids of the mycobacteria keep this stain when decolorising with the acid alcohol. The method is more rapid and sensitive than ZN technique.
Method
Smears are prepared just like that for ZN staining
Stain with Auramine-Phenol for 20 mins
Rinse with water
Decolourise in acid alcohol
Rinse with water
Counterstain with 0.1% potassium permanganate for 30 seconds
Rinse and air dry |
https://en.wikipedia.org/wiki/Aponeurosis%20of%20the%20abdominal%20external%20oblique%20muscle | The aponeurosis of the abdominal external oblique muscle is a thin but strong membranous structure, the fibers of which are directed downward and medially.
It is joined with that of the opposite muscle along the middle line, and covers the whole of the front of the abdomen; above, it is covered by and gives origin to the lower fibers of the pectoralis major; below, its fibers are closely aggregated together, and extend obliquely across from the anterior superior iliac spine to the pubic tubercle and the pectineal line to form the inguinal ligament.
In the middle line, it interlaces with the aponeurosis of the opposite muscle, forming the linea alba, which extends from the xiphoid process to the pubic symphysis.
That portion of the aponeurosis which extends between the anterior superior iliac spine and the pubic tubercle is a thick band, folded inward, and continuous below with the fascia lata; it is called the inguinal ligament.
The portion which is reflected from the inguinal ligament at the pubic tubercle is attached to the pectineal line and is called the lacunar ligament.
From the point of attachment of the latter to the pectineal line, a few fibers pass upward and medialward, behind the medial crus of the superficial inguinal ring, to the linea alba; they diverge as they ascend, and form a thin triangular fibrous band which is called the reflected inguinal ligament.
In the aponeurosis of the external oblique, immediately above the pubic crest, is a triangular opening, the superficial inguinal ring, formed by a separation of the fibers of the aponeurosis in this situation. |
https://en.wikipedia.org/wiki/Windows%20software%20trace%20preprocessor | The Windows software trace preprocessor (WPP; the preprocessor and related support tools are known as WPP Software Tracing) is a preprocessor that simplifies the use of WMI event tracing to implement efficient software tracing in drivers and applications that target Windows 2000 and later operating systems. WPP was created by Microsoft and is included in the Windows DDK. Although WPP is wide in its applicability, it is not included in the Windows SDK, and therefore is primarily used for drivers and driver support software produced by software vendors that purchase the Windows DDK.
Background
Software tracing is a specialized use of logging to record information about a program's execution. This information is commonly used for debugging. In contrast to event logging, the primary purpose of which is to produce records of events that can be audited by system administrators (see for example Event Viewer) or analyzed by management tools, software tracing is primarily a debugging aid for software developers. As such, many of the non-functional requirements of event logging, such as localizability or a standards-based output format, are explicitly non-goals for most applications of software tracing. On the other hand, software tracing has special requirements for performance that are not generally as important in event logging. For example, one common use of software tracing, in/out tracing, produces output at the entry point and return of functions or methods so that a developer can visually follow the execution path, often including parameters and return values, in a debugger or text-based log file (this can be seen as a run-time analog of a sequence diagram). This type of tracing, although useful for developers, can greatly hurt performance of a software product if it cannot be disabled (either at compile-time via conditional compilation, or at run-time via flags).
Additional considerations special to software tracing include the following:
In proprietary s |
https://en.wikipedia.org/wiki/Electronicam | Electronicam was a television recording system that shot an image on film and television at the same time through a common lens. It was developed by James L. Caddigan for the DuMont Television Network in the 1950s, before electronic recording on videotape was available. Since the film directly captured the live scene, its quality was much higher than the commonly used kinescope films, which were shot from a TV screen.
How it worked
The image passes through a lens into a beam splitter that sends half the light to a 35 mm or 16 mm camera mounted on the right side of the television camera. The other half of the light passes to the other side, through a 45-degree angle mirror and into a video camera tube. Because the camera dollies had to support two cameras—one conventional electronic "image orthicon" TV camera tube, and one 35mm motion picture camera—the system was bulky and heavy, and somewhat clumsy in operation. This made complex productions problematic. Single-stage shows, such as The Honeymooners, were relatively easy since they had few sets and generally small casts.
In the studio, when two or three Electronicam cameras were used, a kinescope system recorded the live feed (as broadcast), so the Electronicam films could later be edited to match. The audio was recorded separately, onto either a magnetic fullcoat (1952, and all later) or as an optical soundtrack negative (pre-1952).
Usage
The DuMont Television Network used Electronicams in 1955 to produce most of its studio-based programming since it had (except for occasional sports events) discontinued use of coaxial cable and microwave links to connect stations. Stations were sent films of shows for broadcast.
The "Classic 39" episodes of The Honeymooners aired during the 1955–56 television season on CBS were shot with Electronicams, which meant they could be rerun on broadcast TV and eventually transferred to home video. Without Electronicams, the half-hour The Honeymooners episodes in the 1955-56 season |
https://en.wikipedia.org/wiki/Microsoft%20Robotics%20Developer%20Studio | Microsoft Robotics Developer Studio (Microsoft RDS, MRDS) is a discontinued Windows-based environment for robot control and simulation that was aimed at academic, hobbyist, and commercial developers and handled a wide variety of robot hardware. It requires a Microsoft Windows 7 operating system or later.
RDS is based on Concurrency and Coordination Runtime (CCR): a .NET Framework-based concurrent library implementation for managing asynchronous parallel tasks. This technique involves using message-passing and a lightweight services-oriented runtime, Decentralized Software Services (DSS), which allows orchestrating multiple services to achieve complex behaviors.
Features include: a visual programming tool, Microsoft Visual Programming Language (VPL) to create and debug robot applications, web-based and windows-based interfaces, 3D simulation (including hardware acceleration), easy access to a robot's sensors and actuators. The primary programming language is C#.
Microsoft Robotics Developer Studio includes support for packages to add other services to the suite. Those currently available include Soccer Simulation and Sumo Competition by Microsoft, and a community-developed Maze Simulator, a program to create worlds with walls that can be explored by a virtual robot, and a set of services for OpenCV.
Components
RDS has four main components:
Concurrency and Coordination Runtime (CCR)
Decentralized Software Services (DSS)
Visual Programming Language (VPL)
Visual Simulation Environment (VSE)
CCR and DSS are also available separately for use in commercial applications that require a high level of concurrency and/or must be distributed across multiple nodes in a network. This package is called the CCR and DSS Toolkit.
Tools
The tools that allow developing an MRDS application contain a graphical environment (Microsoft Visual Programming Language (VPL)) command line tools allow working with Visual Studio projects (VS Express version is enough) in C#, and 3D simul |
https://en.wikipedia.org/wiki/Miniature%20Railroad%20%26%20Village | The Miniature Railroad & Village (MRRV) is a large and detailed model train layouts diorama of western Pennsylvania from 1880 to 1930. It is a long-running display currently located in the Carnegie Science Center in Pittsburgh, Pennsylvania, the MRRV has been a Pittsburgh tradition for over 50 years.
History
The exhibit was initiated by Charles Bowdish (1896–1988) of Brookville, Pennsylvania. Bowdish was a soldier during World War I. When doctors discovered a congenital heart problem, he was honorably discharged from service and sent home, where he began to build models of structures around Brookville, his hometown. Every Christmas, in his home on Creek Street (the house has since been demolished), the buildings were assembled in a display, complete with Lionel trains running through it. On Christmas Eve 1920, Charles hosted his brother's wedding and reception, and entertained the guests by running his train display. One of the guests, Alfred Truman, asked if he could bring some friends over to see it—word quickly spread, and nearly 600 people showed up.
Because of this, Christmas Eve 1920 is considered to be the birth date of the exhibit.
Bowdish soon began setting up and exhibiting his railroad yearly at Christmas time in his house. Each year there would be a different theme, such as White Christmas or Indian Summer. The railroad spanned the entire second floor, and no admission fee was ever charged. Thousands of people saw it over the years, some coming from other countries. A combination of a flood nearly destroying his stored models, and his insurance company refusing to cover the crowds anymore, forced Charles to begin searching for a new home for his work. He originally offered it to Brookville, but the town declined.
Eventually he offered it to the Buhl Planetarium and Institute of Popular Science in Pittsburgh (renamed Buhl Science Center in the 1970s). The Buhl offered him space, and the exhibit opened there on December 1, 1954, and ran u |
https://en.wikipedia.org/wiki/Achilles%20number | An Achilles number is a number that is powerful but not a perfect power. A positive integer is a powerful number if, for every prime factor of , is also a divisor. In other words, every prime factor appears at least squared in the factorization. All Achilles numbers are powerful. However, not all powerful numbers are Achilles numbers: only those that cannot be represented as , where and are positive integers greater than 1.
Achilles numbers were named by Henry Bottomley after Achilles, a hero of the Trojan war, who was also powerful but imperfect. Strong Achilles numbers are Achilles numbers whose Euler totients are also Achilles numbers.
Sequence of Achilles numbers
A number is powerful if . If in addition the number is an Achilles number.
The Achilles numbers up to 5000 are:
72, 108, 200, 288, 392, 432, 500, 648, 675, 800, 864, 968, 972, 1125, 1152, 1323, 1352, 1372, 1568, 1800, 1944, 2000, 2312, 2592, 2700, 2888, 3087, 3200, 3267, 3456, 3528, 3872, 3888, 4000, 4232, 4500, 4563, 4608, 5000 .
The smallest pair of consecutive Achilles numbers is:
5425069447 = 73 × 412 × 972
5425069448 = 23 × 260412
Examples
108 is a powerful number. Its prime factorization is 22 · 33, and thus its prime factors are 2 and 3. Both 22 = 4 and 32 = 9 are divisors of 108. However, 108 cannot be represented as , where and are positive integers greater than 1, so 108 is an Achilles number.
360 is not an Achilles number because it is not powerful. One of its prime factors is 5 but 360 is not divisible by 52 = 25.
Finally, 784 is not an Achilles number. It is a powerful number, because not only are 2 and 7 its only prime factors, but also 22 = 4 and 72 = 49 are divisors of it. It is a perfect power:
So it is not an Achilles number.
500 = 22 × 53 is a strong Achilles number as its Euler totient of 200 = 23 × 52 is also an Achilles number. |
https://en.wikipedia.org/wiki/K%20correction | K correction converts measurements of astronomical objects into their respective rest frames. The correction acts on that object's observed magnitude (or equivalently, its flux). Because astronomical observations often measure through a single filter or bandpass, observers only measure a fraction of the total spectrum, redshifted into the frame of the observer. For example, to compare measurements of stars at different redshifts viewed through a red filter, one must estimate K corrections to these measurements in order to make comparisons. If one could measure all wavelengths of light from an object (a bolometric flux), a K correction would not be required, nor would it be required if one could measure the light emitted in an emission line.
Carl Wilhelm Wirtz (1918), who referred to the correction as a Konstanten k (German for "constant") - correction dealing with the effects of redshift of in his work on Nebula. English-speaking claim for the origin of the term "K correction" is Edwin Hubble, who supposedly arbitrarily chose to represent the reduction factor in magnitude due to this same effect and who may not have been aware / given credit to the earlier work.
The K-correction can be defined as follows
I.E. the adjustment to the standard relationship between absolute and apparent magnitude required to correct for the redshift effect. Here, DL is the luminosity distance measured in parsecs.
The exact nature of the calculation that needs to be applied in order to perform a K correction depends upon the type of filter used to make the observation and the shape of the object's spectrum. If multi-color photometric measurements are available for a given object thus defining its spectral energy distribution (SED), K corrections then can be computed by fitting it against a theoretical or empirical SED template. It has been shown that K corrections in many frequently used broad-band filters for low-redshift galaxies can be precisely approximated using two-dimensio |
https://en.wikipedia.org/wiki/Crura%20of%20superficial%20inguinal%20ring | The superficial inguinal ring is bounded below by the crest of the pubis; on either side by the margins of the opening in the aponeurosis, which are called the crura of the ring; and above, by a series of curved intercrural fibers.
The inferior crus (or lateral, or external pillar) is the stronger and is formed by that portion of the inguinal ligament which is inserted into the pubic tubercle; it is curved so as to form a kind of groove, upon which, in the male, the spermatic cord rests.
The superior crus (or medial, or internal pillar) is a broad, thin, flat band, attached to the front of the pubic symphysis and interlacing with its fellow of the opposite side.
See also
Wiktionary: crus |
https://en.wikipedia.org/wiki/Lookahead%20carry%20unit | A lookahead carry unit (LCU) is a logical unit in digital circuit design used to decrease calculation time in adder units and used in conjunction with carry look-ahead adders (CLAs).
4-bit adder
A single 4-bit CLA is shown below:
16-bit adder
By combining four 4-bit CLAs, a 16-bit adder can be created but additional logic is needed in the form of an LCU.
The LCU accepts the group propagate () and group generate () from each of the four CLAs. and have the following expressions for each CLA adder:
The LCU then generates the carry input for each CLA.
Assume that is and is from the ith CLA then the output carry bits are
Substituting into , then into , then into yields the expanded equations:
corresponds to the carry input into the second CLA; to the third CLA; to the fourth CLA; and to overflow carry bit.
In addition, the LCU can calculate its own propagate and generate:
64-bit adder
By combining 4 CLAs and an LCU together creates a 16-bit adder.
Four of these units can be combined to form a 64-bit adder.
An additional (second-level) LCU is needed that accepts the propagate () and generate () from each LCU and the four carry outputs generated by the second-level LCU are fed into the first-level LCUs. |
https://en.wikipedia.org/wiki/Herpetarium | A herpetarium is a zoological exhibition space for reptiles and amphibians, most commonly a dedicated area of a larger zoo. A herpetarium which specializes in snakes is an ophidiarium or serpentarium, which are more common as stand-alone entities also known as snake farms. Many snake farms milk snakes for venom for medical and scientific research.
Notable herpetariums
Alice Springs Reptile Centre in Alice Springs, Australia
Armadale Reptile Centre in Perth, Australia
Australian Reptile Park in Somersby, Australia
Chennai Snake Park Trust in Chennai, India
Crocodiles of the World in Brize Norton, UK
Crocosaurus Cove in Darwin, Australia
Clyde Peeling's Reptiland in Allenwood, Pennsylvania
Kentucky Reptile Zoo in Slade, Kentucky
The LAIR at the Los Angeles Zoo in Los Angeles, California
Serpent Safari in Gurnee, Illinois
Saint Louis Zoo Herpetarium in St. Louis, Missouri
Staten Island Zoo Serpentarium in New York City, New York
World of Reptiles at the Bronx Zoo in New York City, New York
See also
Herpetoculture
Bill Haast (founder of Miami Serpentarium) |
https://en.wikipedia.org/wiki/List%20of%20common%20microcontrollers | This is a list of common microcontrollers listed by brand.
Altera
In 2015, Altera was acquired by Intel.
Nios II 32-bit configurable soft microprocessor
Nios 16-bit configurable soft processor
Analog Devices
Blackfin
Super Harvard Architecture Single-Chip Computer (SHARC)
TigerSHARC
ADSP-21xx digital signal processor
MicroConverter Family – ARM7 and 8051 cores
ARM
While Arm is a fabless semiconductor company (it does not manufacture or sell its own chips), it licenses the ARM architecture family design to a variety of companies.
Those companies in turn sell billions of ARM-based chips per year—12 billion ARM-based chips shipped in 2014,
about
24 billion ARM-based chips shipped in 2020,
some of those are popular chips in their own right.
Atmel
In 2016, Atmel was sold to Microchip Technology.
AT89 series (Intel 8051 architecture)
AT90, ATtiny, ATmega, ATxmega series (AVR architecture) (Atmel Norway design)
AT91SAM (ARM architecture)
AVR32 (32-bit AVR architecture) (Atmel Norway design)
MARC4
Cypress Semiconductor
In 2020, Cypress Semiconductor was acquired by Infineon Technologies.
CY8C2xxxx (PSoC1), M8C
CY8C3xxxx (PSoC3), 8051
CY8C4xxxx (PSoC4), ARM Cortex-M0
CY8C5xxxx (PSoC5), ARM Cortex-M3
PSoC (Programmable System on Chip)
ELAN Microelectronics Corp.
ELAN Microelectronics Corporation is an IC designer and provider of 8-bit microcontrollers and PC Peripheral ICs. Headquartered in Hsinchu Science Park, the Silicon Valley of Taiwan, ELAN's microcontroller product range includes the following:
EM78PXXX Low Pin-Count MCU Family
EM78PXXX GPIO Type MCU Family
EM78PXXXN ADC Type MCU Family
These are clones of the 12- and 14-bit Microchip PIC line of processors, but with a 13-bit instruction word.
EPSON Semiconductor
4-bit
S1C6x family
8-bit
S1C88 family
16-bit
S1C17 family
32-bit
S1C33 family
Espressif Systems
Espressif Systems, a company with headquarters in Shanghai, China made its debut in the microcontroller scene with their |
https://en.wikipedia.org/wiki/List%20of%20national%20flags%20by%20design | A national flag is a flag that represents and symbolizes a country. Flags come in many shapes and designs, which often represent something about the country or people that the flag represents. Common design elements of flags include shapes such as stars, stripes, and crosses, layout elements such as including a canton (a rectangle with a distinct design, such as another national flag), and the overall shape of a flag, such as the aspect ratio of a rectangular flag (whether the flag is square or rectangle, and how wide it is) or the choice of a non-rectangular flag. Sometimes these flags are used to represent languages.
Many countries with shared history, culture, ethnicity, or religion have similarities in their flags that represent this connection. Sets of flags in this list within the same category may represent countries' shared connections, or the design similarity may be a coincidence.
Flags of uncommon shapes
* Most common aspect ratio is 2:3, followed by 1:2.
: Aspect ratio of 13:15
: Aspect ratio of 189:335
: Aspect ratio of 4:5
: The only national flag that is not rectangular, being made with 5 sides. Bordering aspect ratio of ~ 5:6
: Aspect ratio of 6:7
: The largest aspect ratio of any national flag, the flag's width 2.545 times as large as the height. Aspect ratio of 11:28
: (Square-shaped) Aspect ratio of 1:1
: The golden ratio which is roughly 1.618035 ; Aspect ratio of 2:3.23607 or ~ 8:13
: Undefined. The aspect ratio is usually defined around 1:1. However, it is not exactly 1:1.
Star
One five-pointed star in center
(unrecognized)
(1946–1992)
See also the list of flags featuring crescents, below, many of which include a five-pointed star in the crescent.
One five-pointed star on hoist
One five-pointed star on canton
Multiple five-pointed stars of equal size
(unrecognized) (7)
(8)
(4)
(4)
(5)
(5)
(partially recognized) (6)
(2)
(3)
(2)
(2)
(5)
(5)
(2)
(7)
(5)
(9)
(varies, based on number of states, currently 50)
(12 |
https://en.wikipedia.org/wiki/Romanesco%20broccoli | Romanesco broccoli (also known as broccolo romanesco, romanesque cauliflower, or romanesco) is in fact a cultivar of the cauliflower (Brassica oleracea var. botrytis), not broccoli (Brassica oleracea var. italica). It is an edible flower bud of the species Brassica oleracea, which also includes regular broccoli and cauliflower. It is chartreuse in color, and has a form naturally approximating a fractal. Romanesco has a nutty flavor and a firmer texture than cauliflower and broccoli when cooked.
Description
Romanesco superficially resembles a cauliflower, but it is chartreuse in color, with the form of a natural fractal. Nutritionally, romanesco is rich in vitamin C, vitamin K, dietary fiber, and carotenoids.
Fractal structure
The inflorescence (the bud) is self-similar in character, with the branched meristems making up a logarithmic spiral, giving a form approximating a natural fractal; each bud is composed of a series of smaller buds, all arranged in yet another logarithmic spiral. This self-similar pattern continues at smaller levels. The pattern is only an approximate fractal since the pattern eventually terminates when the feature size becomes sufficiently small. The number of spirals on the head of Romanesco broccoli is a Fibonacci number.
The causes of its differences in appearance from the normal cauliflower and broccoli have been modeled as an extension of the preinfloresence stage of bud growth. A 2021 paper has ascribed this phenomenon to perturbations of floral gene networks that causes the development of meristems into flowers to fail, but instead to repeat itself in a self-similar way.
See also
Phyllotaxis |
https://en.wikipedia.org/wiki/Benzimidazole%20fungicide | Benzimidazole fungicides are a class of fungicides including benomyl, carbendazim (MBC), thiophanate-methyl, thiabendazole and fuberidazole. They can control many ascomycetes and basidiomycetes, but not oomycetes. They are applied to cereals, fruits, vegetables and vines, and are also used in postharvest handling of crops.
The solubility of benzimidazole fungicides is low at physiological pH and becomes high at low pH. In plants, carbendazim, thiabendazole and fuberidazole are mobile, i.e. systemic, and benomyl and thiophanate-methyl are converted to carbendazim. This conversion also occurs in soils and animals. In soil and water, carbendazim is mainly degraded by microbes. They are metabolized through hydrolysis and photolysis in plants. These fungicides kill cells during mitosis by distorting the mitotic spindle; β-tubulin, a protein important in forming the cytoskeleton, is targeted. They mostly inhibit polymerization of β-tubulin by interacting with it directly, but other interactions also exist.
Starting in the late 1960s, they were widely used to control fungal pathogens such as Botrytis cinerea, Cercospora, powdery mildew and eyespot. These systemic fungicides were very effective at first. Because there is only one target site, – fungicide resistance to this class – quickly became a serious problem. When they were the only fungicides used, pathogens became resistant after two to four seasons; when mixed with other fungicides, resistance developed more slowly. Resistant genotypes with certain point mutations were selected. Mutant pathogens resistant to one benzimidazole fungicide are usually resistant to all of them. The F200Y and E198A,G,K mutations are the most common. Because of resistance problems, use of benzimidazole fungicides has declined. They are suspected to be toxic to animals, including humans. The Fungicide Resistance Action Committee lists them as having a high risk of resistance evolution. |
https://en.wikipedia.org/wiki/Cauchy%20matrix | In mathematics, a Cauchy matrix, named after Augustin-Louis Cauchy, is an m×n matrix with elements aij in the form
where and are elements of a field , and and are injective sequences (they contain distinct elements).
The Hilbert matrix is a special case of the Cauchy matrix, where
Every submatrix of a Cauchy matrix is itself a Cauchy matrix.
Cauchy determinants
The determinant of a Cauchy matrix is clearly a rational fraction in the parameters and . If the sequences were not injective, the determinant would vanish, and tends to infinity if some tends to . A subset of its zeros and poles are thus known. The fact is that there are no more zeros and poles:
The determinant of a square Cauchy matrix A is known as a Cauchy determinant and can be given explicitly as
(Schechter 1959, eqn 4; Cauchy 1841, p. 154, eqn. 10).
It is always nonzero, and thus all square Cauchy matrices are invertible. The inverse A−1 = B = [bij] is given by
(Schechter 1959, Theorem 1)
where Ai(x) and Bi(x) are the Lagrange polynomials for and , respectively. That is,
with
Generalization
A matrix C is called Cauchy-like if it is of the form
Defining X=diag(xi), Y=diag(yi), one sees that both Cauchy and Cauchy-like matrices satisfy the displacement equation
(with for the Cauchy one). Hence Cauchy-like matrices have a common displacement structure, which can be exploited while working with the matrix. For example, there are known algorithms in literature for
approximate Cauchy matrix-vector multiplication with ops (e.g. the fast multipole method),
(pivoted) LU factorization with ops (GKO algorithm), and thus linear system solving,
approximated or unstable algorithms for linear system solving in .
Here denotes the size of the matrix (one usually deals with square matrices, though all algorithms can be easily generalized to rectangular matrices).
See also
Toeplitz matrix
Fay's trisecant identity |
https://en.wikipedia.org/wiki/Minor%20spliceosome | The minor spliceosome is a ribonucleoprotein complex that catalyses the removal (splicing) of an atypical class of spliceosomal introns (U12-type) from messenger RNAs in some clades of eukaryotes. This process is called noncanonical splicing, as opposed to U2-dependent canonical splicing. U12-type introns represent less than 1% of all introns in human cells. However they are found in genes performing essential cellular functions.
Early evidence
A notable feature of eukaryotic nuclear pre-mRNA introns is the relatively high level of conservation of the primary sequences of 5' and 3' splice sites over a great range of organisms.
Between 1989 and 1991, several groups reported four independent examples of introns with a splice site that differed from the common intron:
Cartilage matrix protein (CMP/MATN1) gene in humans and chickens
Proliferating cell nucleolar protein P120 (NOL1) gene in humans
Mouse Rep3 gene, presumably involved in DNA repair
Drosophila prospero gene that encodes for a homeobox protein
In 1991 by comparing the intron sequences of P120 and CMP genes, IJ Jackson reported the existence of ATATCC (5') and YYCAC (3') splice sites in these introns. The finding indicated a possible novel splicing mechanism.
In 1994, S.L. Hall and R.A. Padgett compared the primary sequence of all reports on the four genes mentioned above. The results suggested a new type of introns with ATATCCTT 5' splice sites and YCCAC 3' splice sites and an almost invariant TCCTTAAC sequence near the 3' end of the introns (so called 3' upstream element). A search for small nuclear RNA sequences that are complementary to these splice sites suggested U12 snRNA (matches the 3' sequence) and U11 snRNA (matches the 5' sequence) as being putative factors involved in splicing of this new type of introns.
In all these four genes, the pre-mRNA contains other introns whose sequences conform to those of major class introns. Neither the size nor the position of the AT–AC intron within t |
https://en.wikipedia.org/wiki/Soul%20of%20a%20Robot | Soul of a Robot is a video game sequel to Nonterraqueous for the ZX Spectrum, Amstrad CPC and MSX, released by Mastertronic in 1985. It was sometimes called Nonterraqueous 2.
Plot
The attempt to destroy the rogue computer from Nonterraqueous failed. Now the computer threatens to self-destruct with old age, taking the planet Nonterraqueous with it. The people of the planet create another robot, one with the mind of a man. On a kamikaze mission to the computer's core, it must locate the three keys to allow it to transport to the next section, before self-destructing inside the computer's core.
Gameplay
Gameplay is rather different from the prequel Nonterraqueous. The robot which is controlled by the player does not "fly" like in the previous game but leaps rather like an ordinary platform game. However, the ability to fly is available in the game, and necessary to complete it. The robot still has a "psyche" value which must not be allowed to decrease to zero and which decreases with certain actions. The "laser" from the previous game also remains.
The game was considered much more difficult than its prequel, relying on perfectly timed and aimed jumps (the player is able to choose five "strengths" of jump) in order to progress, and enjoyed much less commercial success. The gameplay was much slower and jumps and flying can take a lot of time and effort to perform correctly. There also seems to be a certain influence from Underwurlde in the gameplay and sounds used in the game.
Soul of a Robot was also a much smaller game, the map containing only a third as many individual screens as its prequel, with only 256 rooms.
External links
Soul of a Robot at CPC Wiki
1985 video games
ZX Spectrum games
Amstrad CPC games
MSX games
Mastertronic games
Video games about robots
Video games developed in the United Kingdom
Video games set on fictional planets |
https://en.wikipedia.org/wiki/Andromeda%E2%80%93Milky%20Way%20collision | The Andromeda–Milky Way collision is a galactic collision predicted to occur in about 4.5 billion years between the two largest galaxies in the Local Group—the Milky Way (which contains the Solar System and Earth) and the Andromeda Galaxy. The stars involved are sufficiently far apart that it is improbable that any of them will individually collide, though some stars will be ejected.
Certainty
The Andromeda Galaxy is approaching the Milky Way at about 300 km/s (186.411 miles per second) as indicated by blueshift. However, the lateral speed (measured as proper motion) is very difficult to measure with sufficient precision to draw reasonable conclusions. Until 2012, it was not known whether the possible collision was definitely going to happen or not. Researchers then used the Hubble Space Telescope to measure the positions of stars in Andromeda in 2002 and 2010, relative to hundreds of distant background galaxies. By averaging over thousands of stars, they were able to obtain the average proper motion with sub-pixel accuracy. The conclusion was that Andromeda is moving southeast in the sky at less than 0.1 milliarc-seconds per year, corresponding to a speed relative to the Sun of less than 200 km/s towards the south and towards the east. Taking also into account the Sun's motion, Andromeda's tangential or sideways velocity with respect to the Milky Way was found to be much smaller than the speed of approach (consistent with zero given the uncertainty) and therefore it will eventually merge with the Milky Way in around 5 billion years.
Such collisions are relatively common, considering galaxies' long lifespans. Andromeda, for example, is believed to have collided with at least one other galaxy in the past, and several dwarf galaxies such as Sgr dSph are currently colliding with the Milky Way and being merged into it.
The studies also suggest that M33, the Triangulum Galaxy—the third-largest and third-brightest galaxy of the Local Group—will participate in the col |
https://en.wikipedia.org/wiki/Fault%20current%20limiter | A fault current limiter (FCL), also known as fault current controller (FCC), is a device which limits the prospective fault current when a fault occurs (e.g. in a power transmission network) without complete disconnection. The term includes superconducting, solid-state and inductive devices.
Applications
Electric power distribution systems include circuit breakers to disconnect power in case of a fault, but to maximize reliability, they wish to disconnect the smallest possible portion of the network. This means that even the smallest circuit breakers, as well as all wiring to them, must be able to disconnect large fault currents.
A problem arises if the electricity supply is upgraded, by adding new generation capacity or by adding cross-connections. Because these increase the amount of power that can be supplied, all of the branch circuits must have their bus bars and circuit breakers upgraded to handle the new higher fault current limit.
This poses a particular problem when distributed generation, such as wind farms and rooftop solar power, is added to an existing electric grid. It is desirable to be able to add additional power sources without large system-wide upgrades.
A simple solution is to add electrical impedance to the circuit. This limits the rate at which current can increase, which limits the level the fault current can rise to before the breaker is opened. However, this also limits the ability of the circuit to satisfy rapidly changing demand, so the addition or removal of large loads causes unstable power.
A fault current limiter is a nonlinear element which has a low impedance at normal current levels, but presents a higher impedance at fault current levels. Further, this change is extremely rapid, before a circuit breaker can trip a few milliseconds later. (High-power circuit breakers are synchronized to the alternating current zero crossing to minimize arcing.)
While the power is unstable during the fault, it is not completely disconne |
https://en.wikipedia.org/wiki/Java%20concurrency | The Java programming language and the Java virtual machine (JVM) is designed to support concurrent programming. All execution takes place in the context of threads. Objects and resources can be accessed by many separate threads. Each thread has its own path of execution, but can potentially access any object in the program. The programmer must ensure read and write access to objects is properly coordinated (or "synchronized") between threads. Thread synchronization ensures that objects are modified by only one thread at a time and prevents threads from accessing partially updated objects during modification by another thread. The Java language has built-in constructs to support this coordination.
Processes and threads
Most implementations of the Java virtual machine run as a single process. In the Java programming language, concurrent programming is primarily concerned with threads (also called lightweight processes). Multiple processes can only be realized with multiple JVMs.
Thread objects
Threads share the process' resources, including memory and open files. This makes for efficient, but potentially problematic, communication. Every application has at least one thread called the main thread. The main thread has the ability to create additional threads as or objects. The Callable interface is similar to Runnable in that both are designed for classes whose instances are potentially executed by another thread. A Runnable, however, does not return a result and cannot throw a checked exception.
Each thread can be scheduled on a different CPU core or use time-slicing on a single hardware processor, or time-slicing on many hardware processors. There is no general solution to how Java threads are mapped to native OS threads. Every JVM implementation can so this differently.
Each thread is associated with an instance of the class Thread. Threads can be managed either by directly using the Thread objects, or indirectly by using abstract mechanisms such as Executors |
https://en.wikipedia.org/wiki/Piriformis%20fascia | The fascia of the Piriformis is very thin and is attached to the front of the sacrum and the sides of the greater sciatic foramen; it is prolonged on the muscle into the gluteal region.
At its sacral attachment around the margins of the anterior sacral foramina it comes into intimate association with and ensheathes the nerves emerging from these foramina.
Hence the sacral nerves are frequently described as lying behind the fascia.
The internal iliac artery, internal iliac vein, and their branches, on the other hand, lie in the subperitoneal tissue in front of the fascia, and the branches to the gluteal region emerge in special sheaths of this tissue, above and below the Piriformis muscle. |
https://en.wikipedia.org/wiki/J-coupling | In nuclear chemistry and nuclear physics, J-couplings (also called spin-spin coupling or indirect dipole–dipole coupling) are mediated through chemical bonds connecting two spins. It is an indirect interaction between two nuclear spins that arises from hyperfine interactions between the nuclei and local electrons. In NMR spectroscopy, J-coupling contains information about relative bond distances and angles. Most importantly, J-coupling provides information on the connectivity of chemical bonds. It is responsible for the often complex splitting of resonance lines in the NMR spectra of fairly simple molecules.
J-coupling is a frequency difference that is not affected by the strength of the magnetic field, so is always stated in Hz.
Vector model and manifestations for chemical structure assignments
The origin of J-coupling can be visualized by a vector model for a simple molecule such as hydrogen fluoride (HF). In HF, the two nuclei have spin . Four states are possible, depending on the relative alignment of the H and F nuclear spins with the external magnetic field. The selection rules of NMR spectroscopy dictate that ΔI = 1, which means that a given photon (in the radio frequency range) can affect ("flip") only one of the two nuclear spins.
J-coupling provides three parameters: the multiplicity (the "number of lines"), the magnitude of the coupling (strong, medium, weak), and the sign of the coupling.
Multiplicity
The multiplicity provides information on the number of centers coupled to the signal of interest, and their nuclear spin. For simple systems, as in 1H–1H coupling in NMR spectroscopy, the multiplicity is one more than the number of adjacent protons which are magnetically nonequivalent to the protons of interest. For ethanol, each methyl proton is coupled to the two methylene protons, so the methyl signal is a triplet, while each methylene proton is coupled to the three methyl protons, so the methylene signal is a quartet.
Nuclei with spins greater th |
https://en.wikipedia.org/wiki/Pelvic%20fascia | The pelvic fasciae are the fascia of the pelvis and can be divided into:
(a) the fascial sheaths of
the Obturator internus muscle (Fascia of the Obturator internus)
the Piriformis muscle (Fascia of the Piriformis)
the pelvic floor
(b) fascia associated with the organs of the pelvis.
Structure
Fascia of pelvic organs
Pelvic fascia extends to cover the organs within the pelvis.
It is attached to the fascia that runs along the pelvic floor along the tendinous arch. The fascia which covers pelvic organs can be divided according to the organs that are covered:
The front is known as the "vesical layer". It forms the anterior and lateral ligaments of the bladder.
In males, its middle lamina crosses the floor of the pelvis between the rectum and vesiculæ seminales as the rectovesical septum; in the female this is perforated by the cervix and is named the transverse cervical ligament.
At the back, the fascia passes to the side of the rectum; it forms a loose sheath for the rectum, but is firmly attached around the anal canal. This portion is known as the "rectal layer".
Fascia of the pelvic floor
Superior
The part of the pelvic fascia on the pelvic floor covers both surfaces of the Levatores ani muscle.
The layer covering the upper surface of the pelvic diaphragm follows, above, the line of origin of the Levator ani and is therefore somewhat variable. In front it is attached to the back of the pubic symphysis about 2 cm above its lower border.
It can then be traced laterally across the back of the superior ramus of the pubis for a distance of about 1.25 cm, when it reaches the obturator fascia.
It is attached to this fascia along a line which pursues a somewhat irregular course to the spine of the ischium.
The irregularity of this line is because the origin of the Levator ani, which in lower forms is from the pelvic brim, is in man lower down, on the obturator fascia.
Tendinous fibers of origin of the muscle are therefore often found extending up toward, |
https://en.wikipedia.org/wiki/Shear%20matrix | In mathematics (particularly linear algebra), a shear matrix or transvection is an elementary matrix that represents the addition of a multiple of one row or column to another. Such a matrix may be derived by taking the identity matrix and replacing one of the zero elements with a non-zero value.
The name shear reflects the fact that the matrix represents a shear transformation. Geometrically, such a transformation takes pairs of points in a vector space that are purely axially separated along the axis whose row in the matrix contains the shear element, and effectively replaces those pairs by pairs whose separation is no longer purely axial but has two vector components. Thus, the shear axis is always an eigenvector of .
Definition
A typical shear matrix is of the form
This matrix shears parallel to the axis in the direction of the fourth dimension of the underlying vector space.
A shear parallel to the axis results in and . In matrix form:
Similarly, a shear parallel to the axis has and . In matrix form:
In 3D space this matrix shear the YZ plane into the diagonal plane passing through these 3 points:
The determinant will always be 1, as no matter where the shear element is placed, it will be a member of a skew-diagonal that also contains zero elements (as all skew-diagonals have length at least two) hence its product will remain zero and will not contribute to the determinant. Thus every shear matrix has an inverse, and the inverse is simply a shear matrix with the shear element negated, representing a shear transformation in the opposite direction. In fact, this is part of an easily derived more general result: if is a shear matrix with shear element , then is a shear matrix whose shear element is simply . Hence, raising a shear matrix to a power multiplies its shear factor by .
Properties
If is an shear matrix, then:
has rank and therefore is invertible
1 is the only eigenvalue of , so and
the eigenspace of (associated with the eig |
https://en.wikipedia.org/wiki/Doubly%20fed%20electric%20machine | Doubly fed electric machines, also slip-ring generators, are electric motors or electric generators, where both the field magnet windings and armature windings are separately connected to equipment outside the machine.
By feeding adjustable frequency AC power to the field windings, the magnetic field can be made to rotate, allowing variation in motor or generator speed. This is useful, for instance, for generators used in wind turbines. DFIG-based wind turbines, because of their flexibility and ability to control active and reactive power, are almost the most interesting wind turbine technology.
Introduction
Doubly fed electrical generators are similar to AC electrical generators, but have additional features which allow them to run at speeds slightly above or below their natural synchronous speed. This is useful for large variable speed wind turbines, because wind speed can change suddenly. When a gust of wind hits a wind turbine, the blades try to speed up, but a synchronous generator is locked to the speed of the power grid and cannot speed up. So large forces are developed in the hub, gearbox, and generator as the power grid pushes back. This causes wear and damage to the mechanism. If the turbine is allowed to speed up immediately when hit by a wind gust, the stresses are lower with the power from the wind gust still being converted to useful electricity.
One approach to allowing wind turbine speed to vary is to accept whatever frequency the generator produces, convert it to DC, and then convert it to AC at the desired output frequency using an inverter. This is common for small house and farm wind turbines. But the inverters required for megawatt-scale wind turbines are large and expensive.
Doubly fed generators are another solution to this problem. Instead of the usual field winding fed with DC, and an armature winding where the generated electricity comes out, there are two three-phase windings, one stationary and one rotating |
https://en.wikipedia.org/wiki/Tissue%20typing | Tissue typing is a procedure in which the tissues of a prospective donor and recipient are tested for compatibility prior to transplantation. Mismatched donor and recipient tissues can lead to rejection of the tissues. There are multiple methods of tissue typing.
Overview
During tissue typing, an individual's human leukocyte antigens (HLA) are identified. HLA molecules are presented on the surface of cells and facilitate interactions between immune cells (such as dendritic cells and T cells) that lead to adaptive immune responses. If HLA from the donor is recognized by the recipient's immune system as different from the recipient's own HLA, an immune response against the donor tissues can be triggered. More specifically, HLA mismatches between organ donors and recipients can lead to the development of anti-HLA donor-specific antibodies (DSAs). DSAs are strongly associated with the rejection of donor tissues in the recipient, and their presence is considered an indicator of antibody-mediated rejection. When donor and recipient HLA are matched, donor tissues are significantly more likely to be accepted by the recipient's immune system. During tissue typing, a number of HLA genes should be typed in both the donor and recipient, including HLA Class I A, B, and C genes, as well as HLA Class II DRB1, DRB3, DRB4, DRB5, DQA1, DQB1, DPA1, and DPB1 genes. HLA typing is made more difficult by the fact that the HLA region is the most genetically variable region in the human genome.
Methods of tissue typing
One of the first methods of tissue typing was through serological typing. In this technique, a donor's blood cells are HLA typed by mixing them with serum containing anti-HLA antibodies. If the antibodies recognize their epitope on the donor's HLA then complement activation occurs leads to cell lysis and death, allowing the cells to take up a dye (trypan blue). This allows for identification of the cells' HLA based indirectly on the specificity of the known antibodies i |
https://en.wikipedia.org/wiki/Phycodnaviridae | Phycodnaviridae is a family of large (100–560 kb) double-stranded DNA viruses that infect marine or freshwater eukaryotic algae. Viruses within this family have a similar morphology, with an icosahedral capsid (polyhedron with 20 faces). As of 2014, there were 33 species in this family, divided among 6 genera. This family belongs to a super-group of large viruses known as nucleocytoplasmic large DNA viruses. Evidence was published in 2014 suggesting that specific strains of Phycodnaviridae might infect humans rather than just algal species, as was previously believed. Most genera under this family enter the host cell by cell receptor endocytosis and replicate in the nucleus. Phycodnaviridae play important ecological roles by regulating the growth and productivity of their algal hosts. Algal species such Heterosigma akashiwo and the genus Chrysochromulina can form dense blooms which can be damaging to fisheries, resulting in losses in the aquaculture industry. Heterosigma akashiwo virus (HaV) has been suggested for use as a microbial agent to prevent the recurrence of toxic red tides produced by this algal species. Phycodnaviridae cause death and lysis of freshwater and marine algal species, liberating organic carbon, nitrogen and phosphorus into the water, providing nutrients for the microbial loop.
Taxonomy
Group: double-stranded DNA
The taxonomy of this family was initially based on host range: chloroviruses infect chlorella-like green algae from freshwaters; whereas, members of the other five genera infect marine microalgae and a some species of brown macroalgae. This was subsequently confirmed by analysis of their B-family DNA polymerases, which indicated that members of the Phycodnaviridae are more closely related to one another, in comparison to other double stranded DNA viruses, forming a monophyletic group. The phycodnaviruses contain six genera: Coccolithovirus, Chlorovirus, Phaeovirus, Prasinovirus, Prymnesiovirus and Raphidovirus. The genera can be dist |
https://en.wikipedia.org/wiki/Allium%20galanthum | Allium galanthum is an Asian species of onion in the amaryllis family, commonly called the snowdrop onion. It is native to Xinjiang, Mongolia, Altay Krai, and Kazakhstan. It grows at elevations of .
Allium galanthum forms a cluster of bulbs, each up to in diameter. Scapes are up to tall. Leaves are tubular, about half as long as the scapes. Umbels are spherical with a large number of white flowers.
Allium galanthum is edible and reportedly has medicinal uses. |
https://en.wikipedia.org/wiki/Allium%20chinense | Allium chinense (also known as Chinese onion, Chinese scallion, glittering chive, Japanese scallion, Kiangsi scallion, and Oriental onion) is an edible species of Allium, native to China, and cultivated in many other countries. Its close relatives include the onion, shallot, leek, chive, and garlic.
Distribution
Allium chinense is native to China (in Anhui, Fujian, Guangdong, Guangxi, Guizhou, Hainan, Henan, Hubei, Hunan, Jiangxi, and Zhejiang provinces). It is naturalized in other parts of Asia as well as in North America.
Uses
Culinary
Owing to its very mild and "fresh" taste, A. chinense is often pickled and served as a side dish in Japan and Vietnam to balance the stronger flavor of some other component in a meal. For example, in Japanese cuisine, it is eaten as a garnish on Japanese curry.
In Vietnam, pickled A. chinense, known as củ kiệu, is often served during Tết (Lunar New Year).
In Japanese, it is known as . Glass bottles of white rakkyō bulb pickles are sold in Asian supermarkets in North America.
Medicinal
Allium chinense is used as a folk medicine in tonics to help the intestines, and as a stomachic.
See also |
https://en.wikipedia.org/wiki/Genital%20branch%20of%20genitofemoral%20nerve | The genital branch of the genitofemoral nerve, also known as the external spermatic nerve in males, is a nerve in the abdomen that arises from the genitofemoral nerve. The genital branch supplies the cremaster muscle and anterior scrotal skin in males, and the skin of the mons pubis and labia majora in females.
Structure
The genital branch of the genitofemoral nerve arises from the ventral primary divisions of L1-L2 spinal nerve roots. It passes outward on the psoas major muscle, and pierces the fascia transversalis, or passes through the deep inguinal ring. It then descends within the spermatic cord. In males, it passes through to the scrotum, where it supplies the cremaster, dartos muscle and gives a few filaments to the skin of the scrotum. In females, it accompanies the round ligament of the uterus, where it terminates as the nerve supplying the skin of the labia majora and mons pubis.
Function
The genital branch of the genitofemoral nerve is responsible for the motor portion of the cremasteric reflex, which describes contraction of the cremasteric muscle when the skin of the superior medial part of the thigh is touched.
See also |
https://en.wikipedia.org/wiki/Cribriform%20fascia | The cribriform fascia, fascia cribrosa also Hesselbach's fascia is the portion of fascia covering the saphenous opening in the thigh. It is perforated by the great saphenous vein and by numerous blood and lymphatic vessels. (A structure in anatomy that is pierced by several small holes is referred to as cribriform from Latin cribrum meaning sieve).
Clinical significance
The cribriform fascia has been proposed for use in preventing new vascularization when surgery is performed at the join between the great saphenous vein and the femoral vein.
Eponym
When the eponym is used, it is named for Franz Kaspar Hesselbach. |
https://en.wikipedia.org/wiki/Magnetic%20dipole%E2%80%93dipole%20interaction | Magnetic dipole–dipole interaction, also called dipolar coupling, refers to the direct interaction between two magnetic dipoles. Roughly speaking, the magnetic field of a dipole goes as the inverse cube of the distance, and the force of its magnetic field on another dipole goes as the first derivative of the magnetic field. It follows that the dipole-dipole interaction goes as the inverse fourth power of the distance.
Suppose and are two magnetic dipole moments that are far enough apart that they can be treated as point dipoles in calculating their interaction energy. The potential energy of the interaction is then given by:
where is the magnetic constant, is a unit vector parallel to the line joining the centers of the two dipoles, and || is the distance between the centers of and . Last term with -function vanishes everywhere but the origin, and is necessary to ensure that vanishes everywhere. Alternatively, suppose and are gyromagnetic ratios of two particles with spin quanta and . (Each such quantum is some integral multiple of .) Then:
where is a unit vector in the direction of the line joining the two spins, and || is the distance between them.
Finally, the interaction energy can be expressed as the dot product of the moment of either dipole into the field from the other dipole:
where is the field that dipole 2 produces at dipole 1, and is the field that dipole 1 produces at dipole 2. It is not the sum of these terms.
The force arising from the interaction between and is given by:
The Fourier transform of can be calculated from the fact that
and is given by
Dipolar coupling and NMR spectroscopy
The direct dipole-dipole coupling is very useful for molecular structural studies, since it depends only on known physical constants and the inverse cube of internuclear distance. Estimation of this coupling provides a direct spectroscopic route to the distance between nuclei and hence the geometrical form of the molecule, or additionally |
https://en.wikipedia.org/wiki/Pattern%20Blocks | Pattern Blocks are a set of mathematical manipulatives developed in the 1960s. The six shapes are both a play resource and a tool for learning in mathematics, which serve to develop spatial reasoning skills that are fundamental to the learning of mathematics. Among other things, they allow children to see how shapes can be composed and decomposed into other shapes, and introduce children to ideas of tilings. Pattern blocks sets are multiple copies of just six shapes:
Equilateral triangle (Green)
60° rhombus (2 triangles) (Blue) that can be matched with two of the green triangles
30° Narrow rhombus (Beige) with the same side-length as the green triangle
Trapezoid (half hexagon or 3 triangles) (Red) that can be matched with three of the green triangles
Regular Hexagon (6 triangles) (Yellow) that can be matched with six of the green triangles
Square (Orange) with the same side-length as the green triangle
All the angles are multiples of 30° (1/12 of a circle): 30° (1×), 60° (2×), 90° (3×), 120° (4×), and 150° (5×).
Use
The block designed with their for both mathematics and play in mind. The advice given in the 1968 EDC Teacher's Guide is: "Take out the blocks, and play with them yourself. Try out some of your own ideas. Then, when you give the blocks to the children, sit back and watch what they do." The blocks are sufficiently mathematically structured that children’s self-directed play can lead to a variety of mathematical experience. Billy Hargrove and JJ Maybanks identifies a number of frequent features of play which occur:
Composing and Decomposing
Symmetry
Patterns
Three Dimensions
Negative Space
Representational
The EDC Teacher's Guide continues: "Many children start by making abstract designs — both symmetrical and asymmetrical. As play continues these designs may become more and more elegant and complex, or they become simple as the child refines his ideas."
An example of their use is given by Meha Agrawal: "Starting from the center, I would add tie |
https://en.wikipedia.org/wiki/Residual%20dipolar%20coupling | The residual dipolar coupling between two spins in a molecule occurs if the molecules in solution exhibit a partial alignment leading to an incomplete averaging of spatially anisotropic dipolar couplings.
Partial molecular alignment leads to an incomplete averaging of anisotropic magnetic interactions such as the magnetic dipole-dipole interaction (also called dipolar coupling), the chemical shift anisotropy, or the electric quadrupole interaction. The resulting so-called residual anisotropic magnetic interactions are useful in biomolecular NMR spectroscopy.
History and pioneering works
NMR spectroscopy in partially oriented media was reported by Alfred Saupe. After this initiation, a several NMR spectra in various liquid crystalline phases were reported (see e.g. ).
A second technique for partial alignment that is not limited by a minimum anisotropy is strain-induced alignment in a gel (SAG). The technique was extensively used to study the properties of polymer gels by means of high-resolution deuterium NMR, but only lately gel alignment was used to induce RDCs in molecules dissolved into the gel. SAG allows the unrestricted scaling of alignment over a wide range and can be used for aqueous as well as organic solvents, depending on the polymer used. As a first example in organic solvents, RDC measurements in stretched polystyrene (PS) gels swollen in CDCl3 were reported as a promising alignment method.
In 1995, NMR spectra were reported for cyanometmyoglobin, which has a very highly anisotropic paramagnetic susceptibility. When taken at very high field, these spectra may contain data that can usefully complement NOEs in determining a tertiary fold.
In 1996 and 1997, the RDCs of a diamagnetic protein ubiquitin were reported. The results were in good agreement with the crystal structures.
Physics
The secular dipolar coupling Hamiltonian of two spins, and is given by:
where
is the reduced Planck constant.
and are the gyromagnetic ratios of spin and spin |
https://en.wikipedia.org/wiki/Mathematical%20Institute%2C%20University%20of%20Oxford | The Mathematical Institute is the mathematics department at the University of Oxford in England. It is one of the nine departments of the university's Mathematical, Physical and Life Sciences Division. The institute includes both pure and applied mathematics (Statistics is a separate department) and is one of the largest mathematics departments in the United Kingdom with about 200 academic staff. It was ranked (in a joint submission with Statistics) as the top mathematics department in the UK in the 2021 Research Excellence Framework. Research at the Mathematical Institute covers all branches of mathematical sciences ranging from, for example, algebra, number theory, and geometry to the application of mathematics to a wide range of fields including industry, finance, networks, and the brain. It has more than 850 undergraduates and 550 doctoral or masters students. The institute inhabits a purpose-built building between Somerville College and Green Templeton College on Woodstock Road, next to the Faculty of Philosophy.
History
The earliest forerunner of the Mathematical Institute was the School of Geometry and Arithmetic in the Bodleian Library's main quadrangle. This was completed in 1620.
Notable mathematicians associated with the university include Christopher Wren who, before his notable career as an architect, made contributions in analytical mathematics, astronomy, and mathematical physics; Edmond Halley who published a series of profound papers on astronomy while Savilian Professor of Geometry in the early 18th century; John Wallis, whose innovations include using the symbol for infinity; Charles Dodgson, who made significant contributions to geometry and logic while also achieving fame as a children's author under his pen name Lewis Carroll; and Henry John Stephen Smith, another Savilian Professor of Geometry, whose work in number theory and matrices attracted international recognition to Oxford mathematics. Dodgson jokingly proposed that the university s |
https://en.wikipedia.org/wiki/Hewitt%20Crane | Hewitt D. Crane (1927–2008) was an American engineer best known for his pioneering work at SRI International on ERMA (Electronic Recording Machine, Accounting), for Bank of America, magnetic digital logic, neuristor logic, the development of an eye-movement tracking device, and a pen-input device for computers.
Early life and career
Crane was born in 1927 in Jersey City, New Jersey. After a stint in the United States Navy as a radar technician during World War II, he worked as a computer maintenance technician for IBM (1949–1952), followed by working on digital computer design under the leadership of John von Neumann at the Institute for Advanced Study, in Princeton, New Jersey (IAS is not affiliated with Princeton University).
He then developed magnetic multiaperture devices (MADs) at RCA Laboratories (now Sarnoff Corporation). In order to develop magnetic logic, Crane controlled the direction of bit flow in magnetic ferrite memory cores. Ferrite logic circuits are inherently more stable than vacuum tubes and transistors, draw no power when unused, and are impervious to electromagnetic interference. In 1959, Crane introduced the all-magnetic logic approach at the Fall Joint Computer Conference, eventually leading to a demonstration of the world's first all-magnetic computer in 1961. The technology was soon commercialized by Aircraft Marine Products (AMP) Inc., under license from SRI, and used primarily in the rapid transit system of New York City and at railroad switching yards, where electro-magnetic interference made electronic computers unfeasible. The development and growth of planar transistors in silicon chips and integrated circuits displaced magnetic core logic, although it may still be useful for extended space missions and other extreme conditions, but using integrated circuit manufacturing techniques (e.g. etching and deposition of a substrate, and not an assembly of discrete magnetic cores). The prototype of the first all-magnetic computer now resides |
https://en.wikipedia.org/wiki/Diff-Quik | Diff-Quik is a commercial Romanowsky stain variant used to rapidly stain and differentiate a variety of pathology specimens. It is most frequently used for blood films and cytopathological smears, including fine needle aspirates. The Diff-Quik procedure is based on a modification of the Wright-Giemsa stain pioneered by Harleco in the 1970s, and has advantages over the routine Wright-Giemsa staining technique in that it reduces the 4-minute process into a much shorter operation and allows for selective increased eosinophilic or basophilic staining depending upon the time the smear is left in the staining solutions.
There are generic brands of such stain, and the trade name is sometimes used loosely to refer to any such stain (much as "Coke" or "Band-Aid" are sometimes used imprecisely).
Usage
Diff-Quik may be utilized on material which is air-dried prior to alcohol fixation rather than immersed immediately (i.e. "wet-fixed"), although immediate alcohol fixation results in improved microscopic detail.
The primary use of Romanowsky-type stains in cytopathology is for cytoplasmic detail, while Papanicolaou stain is used for nuclear detail. Diff-Quik stain highlights cytoplasmic elements such as mucins, fat droplets and neurosecretory granules. Extracellular substances, such as free mucin, colloid, and ground substance, are also easily stained, and appear metachromatic. Major applications include blood smears, bone marrow aspirates, semen analysis and cytology of various body fluids including urine and cerebrospinal fluid. Microbiologic agents, such as bacteria and fungi, also appear more easily in Diff-Quik. This is useful for the detection of for example Helicobacter pylori from gastric and pyloric specimens.
Due to its short staining time, Diff-Quik stain is often used for initial screening of cytopathology specimens. This staining technique allows the cytotechnologist or pathologist to quickly assess the adequacy of the specimen, identify possible neoplastic or |
https://en.wikipedia.org/wiki/Tonofibril | Tonofibrils are cytoplasmic protein structures in epithelial tissues that converge at desmosomes and hemidesmosomes. They consist of fine fibrils in epithelial cells that are anchored to the cytoskeleton. They were discovered by Rudolf Heidenhain, and first described in detail by Louis-Antoine Ranvier in 1897.
Composition
Tonofilaments are keratin intermediate filaments that makes up tonofibrils in the epithelial tissue. In epithelial cells, tonofilaments loop through desmosomes. Electron microscopy has advanced now to illustrate the tonofilaments more clearly.
The protein filaggrin is believed to be synthesized as a giant precursor protein, profilaggrin (>400 kDA in humans). When filaggrin binds to keratin intermediate filaments, the keratin aggregates into macrofibrils. |
https://en.wikipedia.org/wiki/Rellich%E2%80%93Kondrachov%20theorem | In mathematics, the Rellich–Kondrachov theorem is a compact embedding theorem concerning Sobolev spaces. It is named after the Austrian-German mathematician Franz Rellich and the Russian mathematician Vladimir Iosifovich Kondrashov. Rellich proved the L2 theorem and Kondrashov the Lp theorem.
Statement of the theorem
Let Ω ⊆ Rn be an open, bounded Lipschitz domain, and let 1 ≤ p < n. Set
Then the Sobolev space W1,p(Ω; R) is continuously embedded in the Lp space Lp∗(Ω; R) and is compactly embedded in Lq(Ω; R) for every 1 ≤ q < p∗. In symbols,
and
Kondrachov embedding theorem
On a compact manifold with boundary, the Kondrachov embedding theorem states that if and then the Sobolev embedding
is completely continuous (compact).
Consequences
Since an embedding is compact if and only if the inclusion (identity) operator is a compact operator, the Rellich–Kondrachov theorem implies that any uniformly bounded sequence in W1,p(Ω; R) has a subsequence that converges in Lq(Ω; R). Stated in this form, in the past the result was sometimes referred to as the Rellich–Kondrachov selection theorem, since one "selects" a convergent subsequence. (However, today the customary name is "compactness theorem", whereas "selection theorem" has a precise and quite different meaning, referring to set-valued functions).
The Rellich–Kondrachov theorem may be used to prove the Poincaré inequality, which states that for u ∈ W1,p(Ω; R) (where Ω satisfies the same hypotheses as above),
for some constant C depending only on p and the geometry of the domain Ω, where
denotes the mean value of u over Ω. |
https://en.wikipedia.org/wiki/Idiosyncratic%20drug%20reaction | Idiosyncratic drug reactions, also known as type B reactions, are drug reactions that occur rarely and unpredictably amongst the population. This is not to be mistaken with idiopathic, which implies that the cause is not known. They frequently occur with exposure to new drugs, as they have not been fully tested and the full range of possible side-effects have not been discovered; they may also be listed as an adverse drug reaction with a drug, but are extremely rare. Some patients have multiple-drug intolerance. Patients who have multiple idiopathic effects that are nonspecific are more likely to have anxiety and depression. Idiosyncratic drug reactions appear to not be concentration dependent. A minimal amount of drug will cause an immune response, but it is suspected that at a low enough concentration, a drug will be less likely to initiate an immune response.
Mechanism
In adverse drug reactions involving overdoses, the toxic effect is simply an extension of the pharmacological effect (Type A adverse drug reactions). On the other hand, clinical symptoms of idiosyncratic drug reactions (Type B adverse drug reactions) are different from the pharmacological effect of the drug.
The proposed mechanism of most idiosyncratic drug reactions is immune-mediated toxicity. To create an immune response, a foreign molecule must be present that antibodies can bind to (i.e. the antigen) and cellular damage must exist. Very often, drugs will not be immunogenic because they are too small to induce immune response. However, a drug can cause an immune response if the drug binds a larger molecule. Some unaltered drugs, such as penicillin, will bind avidly to proteins. Others must be bioactivated into a toxic compound that will in turn bind to proteins. The second criterion of cellular damage can come either from a toxic drug/drug metabolite, or from an injury or infection.
These will sensitize the immune system to the drug and cause a response.
Idiosyncratic reactions fall convent |
https://en.wikipedia.org/wiki/First-order%20reduction | In computer science, a first-order reduction is a very strong type of reduction between two computational problems in computational complexity theory. A first-order reduction is a reduction where each component is restricted to be in the class FO of problems calculable in first-order logic.
Since we have , the first-order reductions are stronger reductions than the logspace reductions.
Many important complexity classes are closed under first-order reductions, and many of the traditional complete problems are first-order complete as well (Immerman 1999 p. 49-50). For example, ST-connectivity is FO-complete for NL, and NL is closed under FO reductions (Immerman 1999, p. 51) (as are P, NP, and most other "well-behaved" classes). |
https://en.wikipedia.org/wiki/Autoimmune%20regulator | The autoimmune regulator (AIRE) is a protein that in humans is encoded by the AIRE gene. It is a 13kb gene on chromosome 21q22.3 that has 545 amino acids. AIRE is a transcription factor expressed in the medulla (inner part) of the thymus. It is part of the mechanism which eliminates self-reactive T cells that would cause autoimmune disease. It exposes T cells to normal, healthy proteins from all parts of the body, and T cells that react to those proteins are destroyed.
Each T cell recognizes a specific antigen when it is presented in complex with a major histocompatibility complex (MHC) molecule by an antigen presenting cell. This recognition is accomplished by the T cell receptors expressed on the cell surface. T cells receptors are generated by randomly shuffled gene segments which results in a highly diverse population of T cells—each with a unique antigen specificity. Subsequently, T cells with receptors that recognize the body's own proteins need to be eliminated while still in the thymus. Through the action of AIRE, medullary thymic epithelial cells (mTEC) express major proteins from elsewhere in the body (so called "tissue-restricted antigens" - TRA) and T cells that respond to those proteins are eliminated through cell death (apoptosis). Thus AIRE drives negative selection of self-recognizing T cells. When AIRE is defective, T cells that recognize antigens normally produced by the body can exit the thymus and enter circulation. This can result in a variety of autoimmune diseases.
The gene was first reported by two independent research groups Aaltonen et al. and Nagamine et al. in 1997 who were able to isolate and clone the gene from human chromosome 21q22.3. Their work was able to show that mutations in the AIRE gene are responsible for the pathogenesis of Autoimmune polyglandular syndrome type I. More insight into the AIRE protein was later provided by Heino et al. in 2000. They showed that AIRE protein is mainly expressed in the thymic medullary epithel |
https://en.wikipedia.org/wiki/Programmable%20matter | Programmable matter is matter which has the ability to change its physical properties (shape, density, moduli, conductivity, optical properties, etc.) in a programmable fashion, based upon user input or autonomous sensing. Programmable matter is thus linked to the concept of a material which inherently has the ability to perform information processing.
History
Programmable matter is a term originally coined in 1991 by Toffoli and Margolus to refer to an ensemble of fine-grained computing elements arranged in space. Their paper describes a computing substrate that is composed of fine-grained compute nodes distributed throughout space which communicate using only nearest neighbor interactions. In this context, programmable matter refers to compute models similar to cellular automata and lattice gas automata. The CAM-8 architecture is an example hardware realization of this model. This function is also known as "digital referenced areas" (DRA) in some forms of self-replicating machine science.
In the early 1990s, there was a significant amount of work in reconfigurable modular robotics with a philosophy similar to programmable matter.
As semiconductor technology, nanotechnology, and self-replicating machine technology have advanced, the use of the term programmable matter has changed to reflect the fact that
it is possible to build an ensemble of elements which can be "programmed" to change their physical properties in reality, not just in simulation. Thus, programmable matter has come to mean "any bulk substance which can be programmed to change its physical properties."
In the summer of 1998, in a discussion on artificial atoms and programmable matter, Wil McCarthy and G. Snyder coined the term "quantum wellstone" (or simply "wellstone") to describe this hypothetical but plausible form of programmable matter. McCarthy has used the term in his fiction.
In 2002, Seth Goldstein and Todd Mowry started the claytronics project at Carnegie Mellon University to |
https://en.wikipedia.org/wiki/CLIP%20%28protein%29 | CLIP or Class II-associated invariant chain peptide is the part of the invariant chain (Ii) that binds to the peptide binding groove of MHC class II and remains there until the MHC receptor is fully assembled. CLIP is one of the most prevalent self peptides found in the thymic cortex of most antigen-presenting cells. The purpose of CLIP is to prevent the degradation of MHC II dimers before antigenic peptides bind, and to prevent autoimmunity.
During MHC II assembly in the endoplasmic reticulum, the invariant chain polypeptide complexes with MHC II heterodimers. In a late endosome/early lysosome, cathepsin S cleaves the invariant chain, leaving CLIP bound to the MHC II complex. In the presence of antigenic peptide fragments, HLA-DM partially binds to the MHC II peptide binding groove and acts as a catalyst, releasing CLIP and allowing peptides to bind. Antigenic peptides have a high affinity for the MHC II groove, and are readily exchanged for CLIP. This occurs in most cells expressing MHC II–however, in B cells, HLA-DO functions as the accessory protein. Both HLA-DM and HLA-DO interact with each other to act as chaperone proteins and prevent the denaturing of MHC II. MHC II with bound antigen is then transported to the plasma membrane for presentation.
CLIP also can affect the differentiation of T cells. MHC II + CLIP complexes are upregulated on maturing dendritic cells, which activate and differentiate T cells into Thelper (Th) and Tcytotoxic (Tc) cells. Th cells can polarize into Th1 or Th2 effector cells depending on the presence of cytokines. High expression of CLIP favors the release of IL-4 and Th2 cell polarization.
CLIP plays an important role in preventing autoimmunity. Since MHC is a polymorphic molecule, mutations that prevent CLIP from binding to MHC II leave the peptide binding groove empty. This could lead to the binding of other self-peptides and destruction of healthy cells. Autoimmune diseases such as rheumatoid arthritis, juvenile dermatomyos |
https://en.wikipedia.org/wiki/Fossa%20of%20vestibule%20of%20vagina | The fossa of vestibule of vagina (or fossa navicularis) is a boat-shaped depression between the vagina/hymen and the frenulum labiorum pudendi. The small openings of the Bartholin's ducts can be seen in the grooves between the hymen and the labia minora, on either side.
Additional Images
See also
Vulval vestibule |
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