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https://en.wikipedia.org/wiki/Second%20opinion
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A second opinion is an opinion on a matter disputed by two or more parties.
Law
In legal cases, a second opinion which contradicts the opinion of a jointly retained expert may be disregarded as not being impartial.
Consumer rights
In cases such as car repairs, a second opinion should be obtained in writing, and the original garage given an opportunity to rectify matters. In the case of clients' disputes with domestic building contractors, the builder may seek a second opinion to confirm their view.
Medicine
A second opinion can be a visit to a physician other than the one a patient has previously been seeing in order to get more information or to hear a differing point of view. Some reasons for which a patient may seek out a second opinion include:
Physician recommends surgery.
Physician diagnoses patient with serious illness (such as cancer).
Physician recommends a treatment for the patient other than what the patient believes is necessary.
When physician recommends elective surgery, it may be required by the insurance plan. In other cases, insurance will not pay for a second opinion.
Patient believes they have a condition that the physician diagnosed incorrectly or failed to diagnose.
The physician themself recommends a second opinion.
Different payment procedures apply to different second opinions. For example, some health plans pay for second opinions for members; many employers offer free second opinion benefits through companies like Grand Rounds or similar companies; and some states have public programs for cancer second opinions.
Workplace disputes
Second opinions may also be obtained by employers.
Professional mediation
Professional mediators may be asked for second opinions regarding whether to proceed to trial or seek a settlement instead.
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https://en.wikipedia.org/wiki/Shephard%27s%20problem
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In mathematics, Shephard's problem, is the following geometrical question asked by Geoffrey Colin Shephard in 1964: if K and L are centrally symmetric convex bodies in n-dimensional Euclidean space such that whenever K and L are projected onto a hyperplane, the volume of the projection of K is smaller than the volume of the projection of L, then does it follow that the volume of K is smaller than that of L?
In this case, "centrally symmetric" means that the reflection of K in the origin, −K, is a translate of K, and similarly for L. If k : Rn → Πk is a projection of Rn onto some k-dimensional hyperplane Πk (not necessarily a coordinate hyperplane) and Vk denotes k-dimensional volume, Shephard's problem is to determine the truth or falsity of the implication
Vk(k(K)) is sometimes known as the brightness of K and the function Vk o k as a (k-dimensional) brightness function.
In dimensions n = 1 and 2, the answer to Shephard's problem is "yes". In 1967, however, Petty and Schneider showed that the answer is "no" for every n ≥ 3. The solution of Shephard's problem requires Minkowski's first inequality for convex bodies and the notion of projection bodies of convex bodies.
See also
Busemann–Petty problem
Notes
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https://en.wikipedia.org/wiki/Monte%20Carlo%20N-Particle%20Transport%20Code
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Monte Carlo N-Particle Transport (MCNP) is a general-purpose, continuous-energy, generalized-geometry, time-dependent, Monte Carlo radiation transport code designed to track many particle types over broad ranges of energies and is developed by Los Alamos National Laboratory. Specific areas of application include, but are not limited to, radiation protection and dosimetry, radiation shielding, radiography, medical physics, nuclear criticality safety, detector design and analysis, nuclear oil well logging, accelerator target design, fission and fusion reactor design, decontamination and decommissioning. The code treats an arbitrary three-dimensional configuration of materials in geometric cells bounded by first- and second-degree surfaces and fourth-degree elliptical tori.
Point-wise cross section data are typically used, although group-wise data also are available. For neutrons, all reactions given in a particular cross-section evaluation (such as ENDF/B-VI) are accounted for. Thermal neutrons are described by both the free gas and S(α,β) models. For photons, the code accounts for incoherent and coherent scattering, the possibility of fluorescent emission after photoelectric absorption, absorption in pair production with local emission of annihilation radiation, and bremsstrahlung. A continuous-slowing-down model is used for electron transport that includes positrons, k x-rays, and bremsstrahlung but does not include external or self-induced fields.
Important standard features that make MCNP very versatile and easy to use include a powerful general source, criticality source, and surface source; both geometry and output tally plotters; a rich collection of variance reduction techniques; a flexible tally structure; and an extensive collection of cross-section data.
MCNP contains numerous flexible tallies: surface current & flux, volume flux (track length), point or ring detectors, particle heating, fission heating, pulse height tally for energy or charge depositi
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https://en.wikipedia.org/wiki/PERISCOP
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The PERISCOP is a pressurized recovery device designed for retrieving deep-sea marine life at depths exceeding 2,000 metres. The device was designed by Bruce Shillito and Gerard Hamel at the Universite Pierre et Marie Curie. The name is an acronym for the French phrase Projet d’Enceinte de Remontée Isobare Servant la Capture d’Organismes Profonds ("Enclosure project for isobaric ascent serving to capture deep organisms").
History
The PERISCOP is a unique pressurized recovery devices that contains three chambers – one for capture, one for recovery under exterior pressure, and one for transfer to the laboratory while maintaining pressure. Previous recovery devices used one chamber for all purposes. An arm designed to capture samples by force of suction is attached to the device. During ascent, pressure is maintained within the chamber by use of pressurized water. Upon surfacing, samples can be observed, filmed, and/or photographed through transparent view ports in the device. Due to fluctuations in atmospheric pressure and temperature recorded pressures during ascent and at the surface may ranged from 74%-111% of the natural pressure at sea depth. The device set a record for the deepest live-fish capture under pressure when it captured a Pachycara at 2,300 m. The previous record was 1,400 m. The capture was the first to be performed at a hydrothermal vent. The device has also recovered several shrimp species (Mirocaris fortunata, Chorocaris chacei, and Rimicaris exoculata) at vent fields Lucky Strike and Rainbow.
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https://en.wikipedia.org/wiki/Hungarian%20Operations%20Research%20Society
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The Hungarian Operations Research Society (HORS) is the professional non-profit society for the scientific field of Operations Research in Hungary. The society is recognized by the International Federation of Operational Research Societies and its subgrouping, the Association of European Operational Research Societies, as the main national society for Operations Research in its country,
Aims and scope
The main aims of the society are to
provide information relevant to the scientific public life in operations research (OR),
spread the OR culture,
build and maintain ties with similar scientific societies at domestic (Bolyai János Mathematical Society, John von Neumann Computer Society) and international (EURO, IFORS) level,
organize domestic and international conferences, workshops.
Hungary has a long tradition in cultivating the theory and application of OR.
Researchers have contributed to several areas of this scientific discipline.
OR is included in the curriculum of college and university education. Among
universities that offer OR related courses and also degree it is worth
mentioning Budapest University of Technology and Economics, Corvinus
University of Budapest, University of Debrecen, Eötvös Loránd University,
Óbuda University, University of Pannonia, Széchenyi István University, and
University of Szeged. The doctoral (PhD) schools of these universities offer
research topics in OR within mathematics, computer science, informatics and
engineering.
The importance of OR has been recognized also by the Hungarian Academy of
Sciences (HAS). As a result, HAS has set up the Academic Committee of
Operations Research. Many members of the committee are also members of HORS.
History
Operations Research (OR) was introduced in Hungary by Prof. András Prékopa in
1959. It rapidly raised considerable interest in academic and industrial
circles. The first Hungarian Conference on Operations Research was held in
1967 with over 100 participants. While subsequent confer
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https://en.wikipedia.org/wiki/Plant%20reproductive%20morphology
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Plant reproductive morphology is the study of the physical form and structure (the morphology) of those parts of plants directly or indirectly concerned with sexual reproduction.
Among all living organisms, flowers, which are the reproductive structures of angiosperms, are the most varied physically and show a correspondingly great diversity in methods of reproduction. Plants that are not flowering plants (green algae, mosses, liverworts, hornworts, ferns and gymnosperms such as conifers) also have complex interplays between morphological adaptation and environmental factors in their sexual reproduction. The breeding system, or how the sperm from one plant fertilizes the ovum of another, depends on the reproductive morphology, and is the single most important determinant of the genetic structure of nonclonal plant populations. Christian Konrad Sprengel (1793) studied the reproduction of flowering plants and for the first time it was understood that the pollination process involved both biotic and abiotic interactions. Charles Darwin's theories of natural selection utilized this work to build his theory of evolution, which includes analysis of the coevolution of flowers and their insect pollinators.
Use of sexual terminology
Plants have complex lifecycles involving alternation of generations. One generation, the sporophyte, gives rise to the next generation, the gametophyte asexually via spores. Spores may be identical isospores or come in different sizes (microspores and megaspores), but strictly speaking, spores and sporophytes are neither male nor female because they do not produce gametes. The alternate generation, the gametophyte, produces gametes, eggs and/or sperm. A gametophyte can be monoicous (bisexual), producing both eggs and sperm, or dioicous (unisexual), either female (producing eggs) or male (producing sperm).
In the bryophytes (liverworts, mosses, and hornworts), the sexual gametophyte is the dominant generation. In ferns and seed plants (inc
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https://en.wikipedia.org/wiki/Gasteroid%20fungi
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The gasteroid fungi are a group of fungi in the Basidiomycota. Species were formerly placed in the obsolete class Gasteromycetes Fr. (literally "stomach fungi"), or the equally obsolete order Gasteromycetales Rea, because they produce spores inside their basidiocarps (fruit bodies) rather than on an outer surface. However, the class is polyphyletic, as such species—which include puffballs, earthstars, stinkhorns, and false truffles—are not closely related to each other. Because they are often studied as a group, it has been convenient to retain the informal (non-taxonomic) name of "gasteroid fungi".
History
Several gasteroid fungi—such as the stinkhorn, Phallus impudicus L.—were formally described by Carl Linnaeus in his original Species Plantarum of 1753, but the first critical treatment of the group was by Christiaan Hendrik Persoon in his Synopsis methodica fungorum of 1801. Until 1981, this book was the starting point for the naming of Gasteromycetes under the International Code of Nomenclature for algae, fungi, and plants. Although the starting point was subsequently put back to 1753, names of gasteroid fungi used in Persoon's book are still sanctioned and cannot be replaced by earlier names. Elias Magnus Fries introduced the name Gasteromycetes for a class of fungi in his Systema Mycologicum of 1821, although (not using a microscope) he included many species of the Ascomycota (such as truffles) within the class. Fries contrasted the Gasteromycetes with the Hymenomycetes, where spores are produced externally on gills, pores, and other surfaces.
This convenient division continued to be used for the next 150 years or so, although by the middle of the twentieth century it had become evident that Gasteromycetes was an artificial class (bringing together a miscellany of unrelated species) and not a natural one. In a 1995 study of British species, by Pegler et al. noted that "these fungi represent an heterogeneous assemblage, a mixture of forms which are derived f
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https://en.wikipedia.org/wiki/U-bit
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In quantum mechanics, the u-bit or ubit is a proposed theoretical entity which arises in attempts to reformulate wave functions using only real numbers instead of the complex numbers conventionally used.
Description
In order to discover the real probability of a given quantum event occurring, the conventional calculation carries out an operation, analogous to squaring, on an associated set of complex numbers. A complex number involves the use of the square root of minus one, a number which is described as "imaginary" in contrast to the familiar "real" numbers used for counting and describing real physical objects. Because the computed result is required to be a real number, information is lost in the computation.
This situation is regarded as unsatisfactory by some researchers, who seek an alternative formulation which does not involve the square root of minus one. Bill Wootters, of Williams College, Williamstown, Massachusetts, and colleagues have derived such a model. This model requires the presence of a universal entity which is quantum-entangled with every quantum wave and which he calls the u-bit.
Mathematically the u-bit may be represented as a vector rotating in a real two-dimensional plane. It has no known physical representation in the real world.
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https://en.wikipedia.org/wiki/International%20Association%20for%20Vegetation%20Science
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The International Association for Vegetation Science (IAVS) promotes contact between scientists and others interested in the study of vegetation ecology, promotes research and publication of research results. In 1939 the International Phytosociological Society (IPS) was founded, with its headquarters in Montpellier, France. After the Second World War it was reconstituted as the Internationale Vereinigung für Vegetationskunde (IVV), which adopted a constitution at the International Botanical Congress of 1954. The current name was adopted in 1981–82.
Publications
The society publishes:
IAVS Bulletin
Journal of Vegetation Science
Applied Vegetation Science
Resolutions
Awards
The Alexander von Humboldt Medal is a prize awarded biennially from 2011 onwards by the association. The award is intended to honor scientists who have contributed greatly to the intellectual development and advancement of vegetation science and plant community ecology. Honorary membership is also bestowed by the society.
Medal recipients
2011 J. Philip Grime
2013 David Tilman
2015 Sandra Lavorel
2017 F. Stuart Chapin III
2019 Pierre Legendre
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https://en.wikipedia.org/wiki/Mir-625%20microRNA%20precursor%20family
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In molecular biology mir-625 microRNA is a short RNA molecule. MicroRNAs function to regulate the expression levels of other genes by several mechanisms. Many microRNAs play important roles in cancer development and progression.
mir-625 and gastric cancer
mir-625 has been shown to be down regulated in gastric cancers. This is important, as mir-625 is responsible for the regulation of metastasis in gastric tumour cells, and therefore downregulation of mir-625 results in increased metastasis. mir-625 is thought to act by inhibiting the ILK protein.
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https://en.wikipedia.org/wiki/Bevil%20Conway
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Bevil Conway is a neuroscientist and artist, and an expert in color. Conway specialises in visual perception in his scientific work, and he often explores the limitations of the visual system in his artwork. At Wellesley College, Conway was Knafel Assistant Professor of Natural Science from 2007 to 2011, and associate professor of Neuroscience until 2016. He was a founding member of the Neuroscience Department at ey. Prior to joining the Wellesley faculty, Conway helped establish the Kathmandu University Medical School in Nepal, where he taught as assistant professor in 2002–03. He currently runs the Sensation, Cognition and Action Unit in the Laboratory of Sensorimotor Research at the National Eye Institute and the National Institute of Mental Health.
Conway was educated at McGill University and Harvard University. On finishing his PhD and post-doctoral work under Margaret Livingstone and David Hubel, Conway was elected a Junior Fellow at the Harvard Society of Fellows, and spent a year as an Alexander von Humboldt Fellow at the University of Bremen, Germany. Conway has held grants from the National Science Foundation, the National Institutes of Health, the Whitehall Foundation, and the Radcliffe Institute for Advanced Study.
Science
Conway's research originally set out to explore the principle of double opponency in the primate visual system, showing (in 2001 and 2006) that color cells in the first stage of cortical processing (V1) compute local ratios of cone activity, making them both color-opponent (red-green and blue-yellow) and spatially opponent, pinning them down as the likely basis for color constancy and the brain's building blocks for constructing hue.
Subsequent work has focused on the representation of color in extrastriate areas of the brain that receive input from V1. In collaboration with Doris Tsao, he used fMRI to identify such functionally defined regions and coined the term "globs" to describe them. In 2007 he used targeted single-unit recor
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https://en.wikipedia.org/wiki/John%20Flinders%20Petrie
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John Flinders Petrie (April 26, 1907 – 1972) was an English mathematician who demonstrated remarkable geometric aptitude in his youth. He met the great geometer Harold Scott MacDonald Coxeter as a student, beginning a lifelong friendship. They collaborated in discovering infinite warped polyhedra and (finite) warped polyhedra in the fourth dimension, analogous to the previous ones. In addition to being the first to realize the importance of the warped polygon that now bears his name, his skills as a draftsperson are still appreciated.
Biography
Petrie was born on April 26, 1907, in Hampstead, London. He was the only son of the renowned Egyptologists Sir William Matthew Flinders Petrie and Hilda Petrie. As a student, he showed the remarkable potential of his mathematical abilities, and his incredible visual memory, which his father also showed, allowed him to visualize complex geometries. While studying at a boarding school, he met Coxeter in a sanatorium while recovering from a minor illness, beginning a friendship that would remain throughout their lives. Looking at a geometry textbook with an appendix on Platonic polyhedra, they wondered why there were only five and tried to increase their number. Petrie commented: How about we put four squares around one corner? In practice, they would lie on a plane, forming a pattern of squares covering the plane. Being clever with words, he called this arrangement a "tesserohedron", reaching the similar structure of triangles a "trigonohedron."
Polyhedral regular tilings
One day in 1926, Petrie told Coxeter that he had discovered two new regular polyhedra, infinite but free of "false vertices" (points distinct from the vertices, where three or more faces meet, like those that characterize regular star polyhedra): one consisting of squares, six at each vertex and another consisting of hexagons, four at each vertex, which form a dual or reciprocal pair. To the common objection that there is no room for more than four squares
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https://en.wikipedia.org/wiki/The%20Day%20of%20the%20Triffids
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The Day of the Triffids is a 1951 post-apocalyptic novel by the English science fiction author John Wyndham. After most people in the world are blinded by an apparent meteor shower, an aggressive species of plant starts killing people. Although Wyndham had already published other novels using other pen name combinations drawn from his real name, this was the first novel published as "John Wyndham".
The story has been made into the 1962 feature film of the same name, three radio drama series (in 1957, 1968 and 2001) and two TV series (in 1981 and 2009). It was nominated for the International Fantasy Award in 1952, and in 2003 the novel was listed on the BBC's survey The Big Read.
It was the inspiration for the zombie movie 28 Days Later. In 2021, the novel was one of six classic science fiction novels by British authors selected by Royal Mail to feature on a series of UK postage stamps.
Summary
The protagonist is Bill Masen, a biologist who has made his living working with triffids—tall, venomous, carnivorous plants capable of locomotion. Due to his background, Bill suspects they were bioengineered in the Soviet Union and accidentally released into the wild. Because of the excellent industrial quality of an oil produced by and obtained from the triffids, there is heavy triffid cultivation around the world.
The narrative begins with Bill in hospital, his eyes bandaged after having been splashed with triffid poison from a stinger. During his recovery he is told of an unexpected green meteor shower. The next morning, he learns that the light from the unusual display has rendered any who watched it blind (later in the book, Bill speculates that the "meteor shower" may have been orbiting satellite weapons, triggered accidentally). After unbandaging his eyes he finds the hospital in chaos, with staff and patients without sight. He wanders through a chaotic London full of blind inhabitants and meets wealthy novelist Josella Playton, whom he rescues after discovering her
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https://en.wikipedia.org/wiki/Candace%20Walkington
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Candace Walkington is an associate professor in the Department of Teaching and Learning at Southern Methodist University, and a recipient of the Presidential Early Career Award for Scientists and Engineers.
Education
Walkington received her B.S. and M.S. in Mathematics from Texas A&M University in 2004 and 2006, respectively. She received her PhD in Mathematics Education in 2010 from the University of Texas, and was an Institute of Education Sciences Postdoctoral Fellow in Mathematical Thinking, Learning, and Instruction at the University of Wisconsin - Madison from 2010 to 2012.
Publications
Walkington has published articles in the Journal of Educational Psychology, American Educational Research Journal, Contemporary Educational Psychology, and Cognitive Research: Principles & Implications.
Research funding
Walkington has received grants from the U.S. Department of Education, and the National Science Foundation.
Honors received
Walkington was awarded the Presidential Early Career Award for Scientists and Engineers in 2019.
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https://en.wikipedia.org/wiki/Radiation%20chemistry
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Radiation chemistry is a subdivision of nuclear chemistry which studies the chemical effects of ionizing radiation on matter. This is quite different from radiochemistry, as no radioactivity needs to be present in the material which is being chemically changed by the radiation. An example is the conversion of water into hydrogen gas and hydrogen peroxide.
Radiation interactions with matter
As ionizing radiation moves through matter its energy is deposited through interactions with the electrons of the absorber. The result of an interaction between the radiation and the absorbing species is removal of an electron from an atom or molecular bond to form radicals and excited species. The radical species then proceed to react with each other or with other molecules in their vicinity. It is the reactions of the radical species that are responsible for the changes observed following irradiation of a chemical system.
Charged radiation species (α and β particles) interact through Coulombic forces between the charges of the electrons in the absorbing medium and the charged radiation particle. These interactions occur continuously along the path of the incident particle until the kinetic energy of the particle is sufficiently depleted. Uncharged species (γ photons, x-rays) undergo a single event per photon, totally consuming the energy of the photon and leading to the ejection of an electron from a single atom. Electrons with sufficient energy proceed to interact with the absorbing medium identically to β radiation.
An important factor that distinguishes different radiation types from one another is the linear energy transfer (LET), which is the rate at which the radiation loses energy with distance traveled through the absorber. Low LET species are usually low mass, either photons or electron mass species (β particles, positrons) and interact sparsely along their path through the absorber, leading to isolated regions of reactive radical species. High LET species are usuall
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https://en.wikipedia.org/wiki/Polynomial%20code
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In coding theory, a polynomial code is a type of linear code whose set of valid code words consists of those polynomials (usually of some fixed length) that are divisible by a given fixed polynomial (of shorter length, called the generator polynomial).
Definition
Fix a finite field , whose elements we call symbols. For the purposes of constructing polynomial codes, we identify a string of symbols with the polynomial
Fix integers and let be some fixed polynomial of degree , called the generator polynomial. The polynomial code generated by is the code whose code words are precisely the polynomials of degree less than that are divisible (without remainder) by .
Example
Consider the polynomial code over with , , and generator polynomial . This code consists of the following code words:
Or written explicitly:
Since the polynomial code is defined over the Binary Galois Field , polynomial elements are represented as a modulo-2 sum and the final polynomials are:
Equivalently, expressed as strings of binary digits, the codewords are:
This, as every polynomial code, is indeed a linear code, i.e., linear combinations of code words are again code words. In a case like this where the field is GF(2), linear combinations are found by taking the XOR of the codewords expressed in binary form (e.g. 00111 XOR 10010 = 10101).
Encoding
In a polynomial code over with code length and generator polynomial of degree ,
there will be exactly code words. Indeed, by definition, is a code word if and only if it is of the form , where (the quotient) is of degree less than . Since there are such quotients available, there are the same number of possible code words.
Plain (unencoded) data words should therefore be of length
Some authors, such as (Lidl & Pilz, 1999), only discuss the mapping as the assignment from data words to code words. However, this has the disadvantage that the data word does not appear as part of the code word.
Instead, the following method is
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https://en.wikipedia.org/wiki/Septum%20%28cell%20biology%29
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A septum in cell biology is the new cell wall that forms between two daughter cells as a result of cell division.
In yeast, septins form a ring structure, to which other proteins are recruited. In particular, chitinase 2 is required, an enzyme that synthesises chitin thereby building up the primary septum. A secondary septum of β-glucans and mannoproteins is then assembled using the enzyme 1,3-Beta-glucan synthase, and the primary septum degraded during cell separation. After degradation of the primary septum, a chitinous bud scar remains on both the mother and daughter cell.
Composition
In Schizosaccharomyces pombe, the primary septum is composed of linear β(1,3)-D-glucan, β(1,6) branches, and α(1,3)-D-glucan. The secondary septum in Schizosaccharomyces pombe is composed of β(1,6)-D-glucan, β(1,6) branches, and α(1,3)-D-glucan. The synthesis of linear β(1,3)-D-glucan for the primary septum is done by the enzyme β(1,3)-D-glucan synthase and regulated by a Rho GTPase. Ags1/Mok1 enzyme is responsible for the synthesis of α(1,3)-D-glucan in the primary septum and secondary septum.
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https://en.wikipedia.org/wiki/Force%20of%20mortality
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In actuarial science, force of mortality represents the instantaneous rate of mortality at a certain age measured on an annualized basis. It is identical in concept to failure rate, also called hazard function, in reliability theory.
Motivation and definition
In a life table, we consider the probability of a person dying from age x to x + 1, called qx. In the continuous case, we could also consider the conditional probability of a person who has attained age (x) dying between ages x and x + Δx, which is
where FX(x) is the cumulative distribution function of the continuous age-at-death random variable, X. As Δx tends to zero, so does this probability in the continuous case. The approximate force of mortality is this probability divided by Δx. If we let Δx tend to zero, we get the function for force of mortality, denoted by :
Since fX(x)=F 'X(x) is the probability density function of X, and S(x) = 1 - FX(x) is the survival function, the force of mortality can also be expressed variously as:
To understand conceptually how the force of mortality operates within a population, consider that the ages, x, where the probability density function fX(x) is zero, there is no chance of dying. Thus the force of mortality at these ages is zero. The force of mortality μ(x) uniquely defines a probability density function fX(x).
The force of mortality can be interpreted as the conditional density of failure at age x, while f(x) is the unconditional density of failure at age x. The unconditional density of failure at age x is the product of the probability of survival to age x, and the conditional density of failure at age x, given survival to age x.
This is expressed in symbols as
or equivalently
In many instances, it is also desirable to determine the survival probability function when the force of mortality is known. To do this, integrate the force of mortality over the interval x to x + t
.
By the fundamental theorem of calculus, this is simply
Let us denote
then tak
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https://en.wikipedia.org/wiki/Off-site%20data%20protection
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In computing, off-site data protection, or vaulting, is the strategy of sending critical data out of the main location (off the main site) as part of a disaster recovery plan. Data is usually transported off-site using removable storage media such as magnetic tape or optical storage. Data can also be sent electronically via a remote backup service, which is known as electronic vaulting or e-vaulting. Sending backups off-site ensures systems and servers can be reloaded with the latest data in the event of a disaster, accidental error, or system crash. Sending backups off-site also ensures that there is a copy of pertinent data that is not stored on-site.
Although some organizations manage and store their own off-site backups, many choose to have their backups managed and stored by third parties who specialize in the commercial protection of off-site data.
Data vaults
The storage of off-site data is also known as vaulting, as backups are stored in purpose-built vaults. There are no generally recognized standards for the type of structure which constitutes a vault. That said, commercial vaults typically fit into three categories:
Underground vaults – often converted defunct cold war military or communications facilities, or even disused mines.
Free-standing dedicated vaults
Insulated chambers sharing facilities – often implemented within existing record center buildings.
Hybrid on site and off-site vaulting
Hybrid on-site and off-site data vaulting, sometimes known as Hybrid Online Backup, involve a combination of Local backup for fast backup and restore, along with Off-site backup for protection against local disasters. This ensures that the most recent data is available locally in the event of need for recovery, while archived data that is needed much less often is stored in the cloud.
Hybrid Online Backup works by storing data to local disk so that the backup can be captured at high speed, and then either the backup software or a D2D2C (Disk to Disk to C
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https://en.wikipedia.org/wiki/Institution%20of%20Electronics%20and%20Telecommunication%20Engineers
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The Institution of Electronics and Telecommunication Engineers (IETE) is India's leading recognized professional society devoted to the advancement of science, technology, electronics, telecommunication and information technology. Founded in 1953, it serves more than 70,000+ members through 60+ centers/sub centers primarily located in India (3 abroad). The Institution provides leadership in scientific and technical areas of direct importance to the national development and economy. Association of Indian Universities (AIU), Union Public Service Commission (UPSC) has recognized AMIETE, ALCCS (Advanced Level Course in Computer Science). Government of India has recognized IETE as a Scientific and Industrial Research Organization (SIRO) and also notified as an educational institution of national eminence. The IETE focuses on advancement of electronics and telecommunication technology. The IETE conducts and sponsors technical meetings, conferences, symposium, and exhibitions all over India, publishes technical and research journals and provides continuing education as well as career advancement opportunities to its members.
IETE today is one of the prominent technical institution to provide education to working professionals in India and is fast expanding its wings across the country through its 60+ centres. Since 1953, IETE has expanded its educational activities in areas of electronics, telecommunications, computer science and information technology. IETE conduct programs by examination, leading to DipIETE equivalent to Diploma in Engineering, AMIETE equivalent to B Tech, and ALCCS equivalent to M Tech. IETE started Dual Degree, Dual Diploma and Integrated programs in December 2011. DipIETE is a three year, six semester course whereas AMIETE is a four year, eight semester course. IETE conducts examination for the above said courses, twice a year once in June and in December. Courses are divided into two sections, Section A and Section B. Courses of IETE are recognized
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https://en.wikipedia.org/wiki/Beach%20Volleyball%20Database
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The Beach Volleyball Database, also known as BVB Info, is an online website that tracks international beach volleyball players, tournaments and history, including results of continental and international tournaments. It is the only website of its kind in the sport of beach volleyball.
Volleyball Magazine calls the website "a reliable source for entries and results." The site also collaborates with the Fédération Internationale de Volleyball (FIVB) to provide tournament notes to the FIVB website.
History
The Beach Volleyball Database was launched online by Dennis Wagner on June 2, 1999. Wagner (nicknamed "Dr. Ono") operates the website on his own, for free.
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https://en.wikipedia.org/wiki/Geronimus%20polynomials
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In mathematics, Geronimus polynomials may refer to one of the several different families of orthogonal polynomials studied by Yakov Lazarevich Geronimus.
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https://en.wikipedia.org/wiki/Galactic%20Federation%20%28ufology%29
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The Galactic Federation is a supposed alliance of extraterrestrial civilizations within the Milky Way. This intergalactic council was allegedly revealed through a few well known people in their networks. It was through channeling that Sheldan Nidle, founder of the Ground Crew Project revealed his awareness. Government officials such as Israel's former head of space security, Haim Eshed, like former Canadian minister of national defence Paul Hellyer before him, Eshed has declared that a "Galactic Federation" not only exists but had rejected our membership because we just aren't ready. The idea that such a federation would exist is popular within UFO religions and certain New Age movements. This federation also appears in many science fiction stories.
Israel's Former Space Security Chief
In 2020, former head of Israel's military space program Haim Eshed has claimed that aliens have made contact with representatives of the United States and Israel over the years. During an interview with the Hebrew-language newspaper Yediot Aharonot, the professor and retired Israeli general said that humanity is not yet ready for contact with extraterrestrials. Eshed told the newspaper that aliens are already among us on Earth, and that different species have formed a "Galactic Federation," akin to those in Star Trek, according to translations from the Jerusalem Post. This "Galactic Federation" would keep itself secret to avoid hysteria until humanity would be ready.
NASA released a statement after these claims went viral, writing that no extraterrestrial life has yet been found and that the search for extraterrestrial life is ongoing.
See also
Ancient astronauts
Xenu
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https://en.wikipedia.org/wiki/Blockhead%20%28thought%20experiment%29
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Blockhead is the name of a theoretical computer system invented as part of a thought experiment by philosopher Ned Block, which appeared in a paper titled "Psychologism and Behaviorism". Block did not name the computer in the paper.
Overview
In "Psychologism and Behaviorism," Block argues that the internal mechanism of a system is important in determining whether that system is intelligent and claims to show that a non-intelligent system could pass the Turing test.
Block asks us to imagine a conversation lasting any given amount of time. He states that given the nature of language, there are a finite number of syntactically- and grammatically-correct sentences that can be used to start a conversation. Consequently, there is a limit to how many "sensible" responses can be made to the first sentence, then to the second sentence, and so on until the conversation ends.
Block then asks the reader to imagine a computer which had been programmed with all the sentences in theory, if not in practice. Block argues that such a machine could continue a conversation with a person on any topic because the computer would be programmed with every sentence that it was possible to use so the computer would be able to pass the Turing test despite the fact that — according to Block — it was not intelligent.
Block says that this does not show that there is only one correct internal structure for generating intelligence but simply that some internal structures do not generate intelligence.
The argument is related to John Searle's Chinese room.
A recent objection to the Blockhead argument is Hanoch Ben-Yami (2005), who agrees that Block's machine lacks intelligence but compares its answers to a poetic dialogue in which one man is whispered romantic poetry to recite to his would-be lover as it answers only what it has been told to answer in advance by its programmers.
Sources
.
.
Theory of computation
Philosophy of artificial intelligence
Thought experiments in philosophy of mi
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https://en.wikipedia.org/wiki/Cloud%20computing
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Cloud computing is the on-demand availability of computer system resources, especially data storage (cloud storage) and computing power, without direct active management by the user. Large clouds often have functions distributed over multiple locations, each of which is a data center. Cloud computing relies on sharing of resources to achieve coherence and typically uses a pay-as-you-go model, which can help in reducing capital expenses but may also lead to unexpected operating expenses for users.
Definition
The United States National Institute of Standards and Technology's definition of cloud computing identifies "five essential characteristics":
On-demand self-service. A consumer can unilaterally provision computing capabilities, such as server time and network storage, as needed automatically without requiring human interaction with each service provider.
Broad network access. Capabilities are available over the network and accessed through standard mechanisms that promote use by heterogeneous thin or thick client platforms (e.g., mobile phones, tablets, laptops, and workstations).
Resource pooling. The provider's computing resources are pooled to serve multiple consumers using a multi-tenant model, with different physical and virtual resources dynamically assigned and reassigned according to consumer demand.
Rapid elasticity. Capabilities can be elastically provisioned and released, in some cases automatically, to scale rapidly outward and inward commensurate with demand. To the consumer, the capabilities available for provisioning often appear unlimited and can be appropriated in any quantity at any time.
Measured service. Cloud systems automatically control and optimize resource use by leveraging a metering capability at some level of abstraction appropriate to the type of service (e.g., storage, processing, bandwidth, and active user accounts). Resource usage can be monitored, controlled, and reported, providing transparency for both the provider and
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https://en.wikipedia.org/wiki/Fungal%20Genetics%20and%20Biology
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Fungal Genetics and Biology is a peer-reviewed scientific journal established in 1977 as Experimental Mycology, obtaining its current title in 1996. It covers experimental investigations of fungi and their traditional allies that relate structure and function to growth, reproduction, morphogenesis, and differentiation.
External links
Elsevier academic journals
English-language journals
Monthly journals
Mycology journals
Academic journals established in 1977
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https://en.wikipedia.org/wiki/Functional%20completeness
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In logic, a functionally complete set of logical connectives or Boolean operators is one which can be used to express all possible truth tables by combining members of the set into a Boolean expression. A well-known complete set of connectives is { AND, NOT }. Each of the singleton sets { NAND } and { NOR } is functionally complete. However, the set { AND, OR } is incomplete, due to its inability to express NOT.
A gate or set of gates which is functionally complete can also be called a universal gate / gates.
A functionally complete set of gates may utilise or generate 'garbage bits' as part of its computation which are either not part of the input or not part of the output to the system.
In a context of propositional logic, functionally complete sets of connectives are also called (expressively) adequate.
From the point of view of digital electronics, functional completeness means that every possible logic gate can be realized as a network of gates of the types prescribed by the set. In particular, all logic gates can be assembled from either only binary NAND gates, or only binary NOR gates.
Introduction
Modern texts on logic typically take as primitive some subset of the connectives: conjunction (); disjunction (); negation (); material conditional (); and possibly the biconditional (). Further connectives can be defined, if so desired, by defining them in terms of these primitives. For example, NOR (sometimes denoted , the negation of the disjunction) can be expressed as conjunction of two negations:
Similarly, the negation of the conjunction, NAND (sometimes denoted as ), can be defined in terms of disjunction and negation. It turns out that every binary connective can be defined in terms of , so this set is functionally complete.
However, it still contains some redundancy: this set is not a minimal functionally complete set, because the conditional and biconditional can be defined in terms of the other connectives as
It follows that the smaller set i
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https://en.wikipedia.org/wiki/Estermann%20measure
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In plane geometry the Estermann measure is a number defined for any bounded convex set describing how close to being centrally symmetric it is. It is the ratio of areas between the given set and its smallest centrally symmetric convex superset. It is one for a set that is centrally symmetric, and less than one for sets whose closure is not centrally symmetric. It is invariant under affine transformations of the plane.
Properties
If is the center of symmetry of the smallest centrally-symmetric set containing a given convex body , then the centrally-symmetric set itself is the convex hull of the union of with its reflection across .
Minimizers
The shapes of minimum Estermann measure are the triangles, for which this measure is 1/2. The curve of constant width with the smallest possible Estermann measure is the Reuleaux triangle.
History
The Estermann measure is named after Theodor Estermann, who first proved in 1928 that this measure is always at least 1/2, and that a convex set with Estermann measure 1/2 must be a triangle. Subsequent proofs were given by Friedrich Wilhelm Levi, by István Fáry, and by Isaak Yaglom and Vladimir Boltyansky.
See also
Kovner–Besicovitch measure, a measure of central symmetry defined using subsets in place of supersets
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https://en.wikipedia.org/wiki/Metcalfe%27s%20law
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Metcalfe's law states that the financial value or influence of a telecommunications network is proportional to the square of the number of connected users of the system (2). The law is named for Robert Metcalfe and first proposed in 1980, albeit not in terms of users, but rather of "compatible communicating devices" (e.g., fax machines, telephones). It later became associated with users on the Ethernet after a 13 September 1993 Forbes article by George Gilder.
Network effects
Metcalfe's law characterizes many of the network effects of communication technologies and networks such as the Internet, social networking and the World Wide Web. Former Chairman of the U.S. Federal Communications Commission Reed Hundt said that this law gives the most understanding to the workings of the Internet. Metcalfe's Law is related to the fact that the number of unique possible connections in a network of nodes can be expressed mathematically as the triangular number , which is asymptotically proportional to .
The law has often been illustrated using the example of fax machines: a single fax machine is useless, but the value of every fax machine increases with the total number of fax machines in the network, because the total number of people with whom each user may send and receive documents increases. Likewise, in social networks, the greater the number of users with the service, the more valuable the service becomes to the community.
History and derivation
Metcalfe's law was conceived in 1983 in a presentation to the 3Com sales force. It stated would be proportional to the total number of possible connections, or approximately -squared.
The original incarnation was careful to delineate between a linear cost (), non-linear growth, 2, and a non-constant proportionality factor , affinity. The break-even point where costs are recouped is given by:
At some size, the right-hand side of the equation , value, exceeds the cost, and describes the relationship between size and net va
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https://en.wikipedia.org/wiki/Annapurna%20Labs
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Annapurna Labs is an Israeli microelectronics company. Since January 2015 it has been a wholly-owned subsidiary of Amazon.com. Amazon reportedly acquired the company for its Amazon Web Services division for US$350–370M.
History
Annapurna Labs, named after the Annapurna Massif in the Himalayas, was co-founded in 2011 by Bilic "Billy" Hrvoje, a Bosnian Jewish refugee, Nafea Bshara, an Arab Israeli citizen, and Ronen Boneh with investments from the independent investors Avigdor Willenz, Manuel Alba, Andy Bechtolsheim, the venture capital firm Walden International, Arm Holdings, and TSMC. Board members include Avigdor Willenz, Manuel Alba, and Lip-Bu Tan, the CEO of both Walden International and Cadence Design Systems.
The first product launched under the AWS umbrella was the AWS Nitro hardware and supporting hypervisor in November 2017. Following on from Nitro, Annapurna developed general-purpose CPUs under the Graviton family and machine-learning ASICs under the Trainium and Inferentia brands.
See also
AWS Graviton - an ARM based CPU developed by Annapurna Labs for exclusive use by Amazon Web Services.
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https://en.wikipedia.org/wiki/Eucheuma
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Eucheuma, commonly known as sea moss or gusô (), is a rhodophyte seaweed that may vary in color (purple, brown, and green). Eucheuma species are used in the production of carrageenan, an ingredient for cosmetics, food processing, and industrial manufacturing, as well as a food source for people in the Philippines, Caribbean and parts of Indonesia and Malaysia. Eucheuma cottonii – which grows in the Caribbean and cultivated in the Philippines – is the particular species known as gusô. Other species include Betaphycus gelatinae, Eucheuma denticulatum, and several species of the genus Kappaphycus, including K. alvarezii. Since the mid-1970s, Kappaphycus and Eucheuma have been a major source for the expansion of the carrageenan industry.
Commercial seaweed farming of gusô (as well as Kappaphycus) was pioneered in the Philippines. Though commercially significant, species of Eucheuma are difficult to identify without the aid of close scientific examination, as different species may have similar morphologies. Some eighteen to twenty species alone fall within the genus Eucheuma, represented by the groups Cottoniformia, Gelatiformia, and Anaxiferae.
Gusô is listed in the Ark of Taste international catalogue of endangered heritage foods of the Philippines by the Slow Food movement.
History
The earliest record of the use of gusô as food is from the Diccionario De La Lengua Bisaya, Hiligueina y Haraia de la isla de Panay y Sugbu y para las demas islas (c.1637) of the Augustinian missionary Alonso de Méntrida . In the book, Méntrida describes gusô as being a type of seaweed gathered from the beach by the Visayan peoples of the Philippines. They were then cooked until they melt, and then allowed to congeal into a sour dish.
The 1889 book The Useful Native Plants of Australia records that Eucheuma speciosa, was commonly known as the "Jelly Plant' in Western Australia and that "This is a remarkable sea-weed of a very gelatinous character which enters into the culinary arrangem
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https://en.wikipedia.org/wiki/Cyclotomic%20polynomial
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In mathematics, the nth cyclotomic polynomial, for any positive integer n, is the unique irreducible polynomial with integer coefficients that is a divisor of and is not a divisor of for any Its roots are all nth primitive roots of unity
, where k runs over the positive integers not greater than n and coprime to n (and i is the imaginary unit). In other words, the nth cyclotomic polynomial is equal to
It may also be defined as the monic polynomial with integer coefficients that is the minimal polynomial over the field of the rational numbers of any primitive nth-root of unity ( is an example of such a root).
An important relation linking cyclotomic polynomials and primitive roots of unity is
showing that is a root of if and only if it is a dth primitive root of unity for some d that divides n.
Examples
If n is a prime number, then
If n = 2p where p is an odd prime number, then
For n up to 30, the cyclotomic polynomials are:
The case of the 105th cyclotomic polynomial is interesting because 105 is the least positive integer that is the product of three distinct odd prime numbers (3*5*7) and this polynomial is the first one that has a coefficient other than 1, 0, or −1:
Properties
Fundamental tools
The cyclotomic polynomials are monic polynomials with integer coefficients that are irreducible over the field of the rational numbers. Except for n equal to 1 or 2, they are palindromes of even degree.
The degree of , or in other words the number of nth primitive roots of unity, is , where is Euler's totient function.
The fact that is an irreducible polynomial of degree in the ring is a nontrivial result due to Gauss. Depending on the chosen definition, it is either the value of the degree or the irreducibility which is a nontrivial result. The case of prime n is easier to prove than the general case, thanks to Eisenstein's criterion.
A fundamental relation involving cyclotomic polynomials is
which means that each n-th root of unity is a primitiv
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https://en.wikipedia.org/wiki/Socket%205
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Socket 5 was created for the second generation of Intel P5 Pentium processors operating at speeds from 75 to 133 MHz as well as certain Pentium OverDrive and Pentium MMX processors with core voltage 3.3 V. It superseded the earlier Socket 4. It was released in March 1994. Consisting of 320 pins, this was the first socket to use a staggered pin grid array, or SPGA, which allowed the chip's pins to be spaced closer together than earlier sockets. Socket 5 was replaced by Socket 7 in 1995.
External links
Differences between Socket 5 and Socket 7 (archived)
See also
List of Intel microprocessors
List of AMD microprocessors
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https://en.wikipedia.org/wiki/Subtepass
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Subtepass is the electronic smartcard used for trips on the Buenos Aires Metro. In addition to the regular Subtepass, there are special discounted and free versions available, based on category. Secondary and tertiary school students may purchase a discounted Abono Estudiantil (Spanish: Student Pass). Teachers that are employed by the city school system may purchase a discounted Abono Maestro (Spanish: Teacher Pass). Students in primary school may ride the metro to and from school for free with a Pase Escolar Primario (Spanish: Primary School Pass), provided they are wearing their white smock uniform. In addition, retirees, pensioners, and certain classes of retired military personnel are eligible for a free Pase Jubilados y Pensionados (Spanish: Retiree and Pensioner Pass). There are also free passes for visually impaired and disabled persons.
In more recent years, the contactless SUBE and Monedero smart cards have been favoured over the Subtepass.
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https://en.wikipedia.org/wiki/List%20of%20finite%20element%20software%20packages
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This is a list of notable software packages that implement the finite element method for solving partial differential equations.
Feature comparison
This table is contributed by a FEA-compare project, which provides an alternative view of this table with the first row and Feature column being fixed for ease of table exploration.
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https://en.wikipedia.org/wiki/Andr%C3%A1s%20Gy%C3%A1rf%C3%A1s
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András Gyárfás (born 1945) is a Hungarian mathematician who specializes in the study of graph theory. He is famous for two conjectures:
Together with Paul Erdős he conjectured what is now called the Erdős–Gyárfás conjecture which states that any graph with minimum degree 3 contains a simple cycle whose length is a power of two.
He and David Sumner independently formulated the Gyárfás–Sumner conjecture according to which, for every tree T, the T-free graphs are χ-bounded.
Gyárfás began working as a researcher for the Computer and Automation Research Institute of the Hungarian Academy of Sciences in 1968. He earned a candidate degree in 1980, and a doctorate (Dr. Math. Sci.) in 1992. He won the Géza Grünwald Commemorative Prize for young researchers of the János Bolyai Mathematical Society in 1978. He was co-author with Paul Erdős on 15 papers, and thus has Erdős number one.
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https://en.wikipedia.org/wiki/Data%20Interchange%20Format
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Data Interchange Format (.dif) is a text file format used to import/export single spreadsheets between spreadsheet programs.
Applications that still support the DIF format are Collabora Online, Excel, Gnumeric, and LibreOffice Calc. Historical applications that used to support it until they became end of life or no longer acknowledge support of the format are dBase, FileMaker, Framework, Lotus 1-2-3, Multiplan, OpenOffice.org Calc and StarCalc.
A limitation with DIF format is that it cannot handle multiple spreadsheets in a single workbook. Due to the similarity in abbreviation and in age (both date to the early 1980s), the DIF spreadsheet format it is often confused with Navy DIF; Navy DIF, however, is an unrelated "document interchange format" for word processors.
History
DIF was developed by Software Arts, Inc. (the developers of the VisiCalc program) in the early 1980s. The specification was included in many copies of VisiCalc, and published in Byte Magazine. Bob Frankston developed the format, with input from others, including Mitch Kapor, who helped so that it could work with his VisiPlot program. (Kapor later went on to found Lotus and make Lotus 1-2-3 happen.) The specification was copyright 1981.
DIF was a registered trademark of Software Arts Products Corp. (a legal name for Software Arts at the time).
Syntax
DIF stores everything in an ASCII text file to mitigate many cross-platform issues back in the days of its creation. However modern spreadsheet software, e.g. OpenOffice.org Calc and Gnumeric, offer more character encoding to export/import. The file is divided into 2 sections: header and data. Everything in DIF is represented by a 2- or 3-line chunk. Headers get a 3-line chunk; data, 2. Header chunks start with a text identifier that is all caps, only alphabetic characters, and less than 32 letters. The following line must be a pair of numbers, and the third line must be a quoted string. On the other hand, data chunks start with a number pair and
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https://en.wikipedia.org/wiki/Galaxian
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is a 1979 fixed shooter arcade video game developed and published by Namco. The player assumes control of the Galaxip starfighter in its mission to protect Earth from waves of aliens. Gameplay involves destroying each formation of aliens, who dive down towards the player in an attempt to hit them.
Designed by company engineer Kazunori Sawano, Galaxian was Namco's answer to Space Invaders, a similar space shooter released the previous year by rival developer Taito. Space Invaders was a sensation in Japan, and Namco wanted a game that could compete against it. Sawano strove to make the game simplistic and easy to understand. He was inspired by the cinematic space combat scenes in Star Wars, with enemies originally being in the shape of the film's TIE Fighters. Galaxian is one of the first video games to feature RGB color graphics and the first ever to use a tile-based hardware system, which was capable of animated multi-color sprites as well as scrolling, though the latter was limited to the starfield background while the game itself remained a fixed shooter.
Galaxian was Namco's first major arcade video game hit. It was the second highest-grossing arcade video game of 1979 and 1980 in Japan and the second highest-grossing of 1980 in the United States, where it became one of the best-selling arcade games of all time with 50,000 arcade units sold by 1982. The game was celebrated for its gameplay and usage of true color graphics. In retrospect, it has gained fame for its historical importance and technological accomplishments. Its success led to several sequels and reimaginings; most notable of these is Galaga, which usurped the original in popularity. Galaxian has also been ported to many home systems and is included in numerous Namco compilations.
Gameplay
Galaxian is a space-themed fixed shooter. The player controls a starship called the "Galaxip", the objective being to clear each round of aliens. The enemies appear in formation towards the top of the screen, wi
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https://en.wikipedia.org/wiki/Undeadline
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is a 1989 vertically scrolling shooter video game developed and originally published by T&E Soft for the MSX2 and MSX2+ home computers. It was later ported to the X68000 computer and Sega Mega Drive, published by Palsoft, followed by digital re-releases for Microsoft Windows. Both the MSX2 and X68000 versions also received physical re-releases by Japanese retailer BEEP. It follows a group of characters in rescue of queen Althea from Zidane, a kingdom surrounded by barriers connected with the demon world, whose monsters have overflowed it. Controlling either a fighter, wizard, or ninja, the player can choose from six stages and play them in any order, fighting against waves of enemies and bosses, while defending or avoiding collision with their projectiles and other obstacles.
Undeadline was directed and designed by Tokihiro Naito, who previously worked on Hydlide and Hydlide 3, with Tetsuya "Futaro" Yamamoto serving as main programmer. The soundtrack was composed by Kazunori Hasegawa. Due to T&E Soft liking to push its playtesters to the limits and as their skills improved naturally, it led to the designers increasing the difficulty to keep up with them, particularly paying attention to both enemy movement and spawn patterns. Because of its rarity, original copies of the MSX2 version commands high prices on the secondary game collecting market. The game received generally favorable reception from critics, most of which reviewed it as an import title, although its difficulty has been criticized.
Gameplay
Undeadline is a vertical-scrolling shoot 'em up game with role-playing elements that plays from a top-down perspective. The plot revolves around Zidane, a country surrounded by barriers connected with the demon world whose monsters have overflowed it after being broken in a previous regime. Queen Althea manages the kingdom, as his father became exhausted from battle and fell ill, but she is kidnapped by a creature from the demon world. Joined by the wizard Dino
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https://en.wikipedia.org/wiki/Open%20Location%20Code
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The Open Location Code (OLC) is a geocode based in a system of regular grids for identifying an area anywhere on the Earth.
It was developed at Google's Zürich engineering office, and released late October 2014. Location codes created by the OLC system are referred to as "plus codes".
Open Location Code is a way of encoding location into a form that is easier to use than showing coordinates in the usual form of latitude and longitude. Plus codes are designed to be used like street addresses, and may be especially useful in places where there is no formal system to identify buildings, such as street names, house numbers, and post codes.
Plus codes are derived from latitude and longitude coordinates, so they already exist everywhere. They are similar in length to a telephone number – 849VCWC8+R9, for example – but can often be shortened to only four or six digits when combined with a locality (CWC8+R9, Mountain View). Locations close to each other have similar codes. They can be encoded or decoded offline. The character set avoids similar looking characters, to reduce confusion and errors, and avoids vowels to make it unlikely that a code spells existing words. Plus codes are not case-sensitive, and can therefore be easily exchanged over the phone.
Since August 2015, Google Maps supports plus codes in its search engine. The algorithm is licensed under the Apache License 2.0. and available on GitHub.
Google has shown practical usage of plus codes for addressing purposes in Cape Verde, parts of Kolkata and Kolhapur in India, and the Navajo Nation in the United States.
Specification
The Open Location Code system is based on latitudes and longitudes in WGS84 coordinates. Each code describes an area bounded by two parallels and two meridians out of a fixed grid, identified by the South-West corner and its size. The largest grid has blocks of 20 by 20 degrees (9 rows and 18 columns), and is divided in 20 by 20 subblocks up to four times. From that level onwards, div
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https://en.wikipedia.org/wiki/Comparability%20graph
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In graph theory, a comparability graph is an undirected graph that connects pairs of elements that are comparable to each other in a partial order. Comparability graphs have also been called transitively orientable graphs, partially orderable graphs, containment graphs, and divisor graphs.
An incomparability graph is an undirected graph that connects pairs of elements that are not comparable to each other in a partial order.
Definitions and characterization
For any strict partially ordered set , the comparability graph of is the graph of which the vertices are the elements of and the edges are those pairs of elements such that . That is, for a partially ordered set, take the directed acyclic graph, apply transitive closure, and remove orientation.
Equivalently, a comparability graph is a graph that has a transitive orientation, an assignment of directions to the edges of the graph (i.e. an orientation of the graph) such that the adjacency relation of the resulting directed graph is transitive: whenever there exist directed edges and , there must exist an edge .
One can represent any finite partial order as a family of sets, such that in the partial order whenever the set corresponding to is a subset of the set corresponding to . In this way, comparability graphs can be shown to be equivalent to containment graphs of set families; that is, a graph with a vertex for each set in the family and an edge between two sets whenever one is a subset of the other.
Alternatively, one can represent the partial order by a family of integers, such that whenever the integer corresponding to is a divisor of the integer corresponding to . Because of this construction, comparability graphs have also been called divisor graphs.
Comparability graphs can be characterized as the graphs such that, for every generalized cycle (see below) of odd length, one can find an edge connecting two vertices that are at distance two in the cycle. Such an edge is called a triangular chor
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https://en.wikipedia.org/wiki/Sori%20%28music%29
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The sori (Persian:سری) is a symbol that corresponds to a quarter step higher in tone in Persian traditional music. It is written as a ">" sign, crossed by two vertical lines, and can be used like an accidental.
In the early 20th century, Iranian master musician Alinaghi Vaziri established this sign for the sori for use in written Persian music using standard western notation. Character representation of this accidental symbol together with Koron encoding (encoded as U+1D1E9 and U+1D1EA) microtones used in modern Iranian classical music added to the Unicode standard in Version 14.0.0.
See also
Persian traditional music
Dastgah
Quarter tone
koron
External links
Persian accidentals in the SMuFL glyph (Standard Music Font Layout)
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https://en.wikipedia.org/wiki/TCF7L2
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Transcription factor 7-like 2 (T-cell specific, HMG-box), also known as TCF7L2 or TCF4, is a protein acting as a transcription factor that, in humans, is encoded by the TCF7L2 gene. The TCF7L2 gene is located on chromosome 10q25.2–q25.3, contains 19 exons. As a member of the TCF family, TCF7L2 can form a bipartite transcription factor and influence several biological pathways, including the Wnt signalling pathway.
Single-nucleotide polymorphisms (SNPs) in this gene are especially known to be linked to higher risk to develop type 2 diabetes, gestational diabetes, multiple neurodevelopmental disorders including schizophrenia and autism spectrum disorder, as well as other diseases. The SNP rs7903146, within the TCF7L2 gene, is, to date, the most significant genetic marker associated with type 2 diabetes risk.
Function
TCF7L2 is a transcription factor influencing the transcription of several genes thereby exerting a large variety of functions within the cell. It is a member of the TCF family that can form a bipartite transcription factor (β-catenin/TCF) alongside β-catenin. Bipartite transcription factors can have large effects on the Wnt signalling pathway. Stimulation of the Wnt signaling pathway leads to the association of β-catenin with BCL9, translocation to the nucleus, and association with TCF7L2, which in turn results in the activation of Wnt target genes. The activation of the Wnt target genes specifically represses proglucagon synthesis in enteroendocrine cells. The repression of TCF7L2 using HMG-box repressor (HBP1) inhibits Wnt signalling. Therefore, TCF7L2 is an effector in the Wnt signalling pathway. TCF7L2's role in glucose metabolism is expressed in many tissues such as gut, brain, liver, and skeletal muscle. However, TCF7L2 does not directly regulate glucose metabolism in β-cells, but regulates glucose metabolism in pancreatic and liver tissues. That said, TCF7L2 directly regulates the expression of multiple transcription factors, axon guidance cues
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https://en.wikipedia.org/wiki/Lorenzo%20de%20Zavala
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Manuel Lorenzo Justiniano de Zavala y Sánchez (October 3, 1788 – November 15, 1836), known simply as Lorenzo de Zavala, was a Mexican and later Tejano physician, politician, diplomat and author. Born in Yucatán under Spanish rule, he was closely involved in drafting the constitution for the First Federal Republic of Mexico in 1824 after Mexico won independence from Spain. Years later, he also helped in drafting a constitution for Mexico's rebellious enemy at the time, the Republic of Texas, to secure independence from Mexico in 1836. Zavala was said to have had a keen intellect and was fluent in multiple languages.
Zavala was one of the most prominent liberals in the era of the First Republic. Since his youth, Zavala was an indefatigable believer in the principle of democratic representative government. As a young man he founded several newspapers and wrote extensively, espousing democratic reforms — writings which led to his imprisonment by the Spanish crown. While imprisoned, he learned English and studied medicine; after his release, he practiced medicine for two years before entering politics.
Over his career, he served in many different capacities including the Spanish Cortes (legislature) in Madrid representing Yucatán, and in Mexico's Senate. He became Mexico's Minister of Finance and served as Ambassador to France and Governor of the State of Mexico. In 1829, a conservative coup brought Anastasio Bustamante to power, and Zavala was forced into exile, moving to the United States for two years. He wrote a book about U.S. political culture during this time and also traveled extensively in Europe. With his diplomatic experience and linguistic skills, Zavala was well received by foreign governments.
In 1832, a liberal coup brought Valentin Gomez Farias to power. Zavala returned to Mexico and was appointed as Minister to France. While serving in Paris, Zavala witnessed overthrow of Gomez Farias and the subsequent fall of the First Mexican Republic. Santa Anna w
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https://en.wikipedia.org/wiki/Scattering%20channel
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In scattering theory, a scattering channel is a quantum state of the colliding system before or after the collision (). The Hilbert space spanned by the states before collision (in states) is equal to the space spanned by the states after collision (out states) which are both Fock spaces if there is a mass gap. This is the reason why the S matrix which maps the in states onto the out states must be unitary. The scattering channel are also called scattering asymptotes. The Møller operators are mapping the scattering channels onto the corresponding states which are solution of the Schrödinger equation taking the interaction Hamiltonian into account. The Møller operators are isometric.
See also
LSZ formalism
Scattering
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https://en.wikipedia.org/wiki/Eugenia%20reinwardtiana
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Eugenia reinwardtiana is a shrub to small tree in the family Myrtaceae. Native to tropical forests in northern Queensland, Indonesia, and the Pacific Islands, its common names include Cedar Bay Cherry, Beach Cherry, Australian Beach, Mountain Stopper, Nioi (Hawaiian), and A'abang (Chamorro). They are typically in height.
The tree is particularly common around the Cedar Bay National Park in northern Australia and the edible fruit was especially popular with the hippies who lived there in the 1970s.
The fruits are green at first, then ripen to a bright orange-red colour with a sweet taste and soft flesh.
Uses
The tree is cultivated to a limited extent for its edible sweetish fruit that is often eaten out-of-hand, used to flavour drinks and candies, or as a preserve. The fruit is a source of antioxidants.
The tree is well-suited to amenity horticulture in the tropics, and is grown in the median strips in Cairns. It is readily propagated from fresh seed.
This species is susceptible to Myrtle Rust (Puccinia psidii).
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https://en.wikipedia.org/wiki/Witches%27%20butter
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Witches' butter (or Witch's butter) may refer to:
Exidia nigricans, a black, gelatinous fungus
Exidia glandulosa, a black, gelatinous fungus
Tremella mesenterica, a yellow, gelatinous fungus
Dacrymyces, a jelly fungus often confused with Tremella
Nostoc, a genus of gelatinous cyanobacteria
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https://en.wikipedia.org/wiki/Viola%20mandshurica
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Viola mandshurica is a perennial species of violet known by the common names (:zh:东北堇菜) meaning 'northeastern violet' in China, (:ko:제비꽃) meaning 'sparrow flower' in Korea, and (:ja:菫, :ja:スミレ) meaning 'violet' in Japan. In Japan, V. mandshurica is considered to be the basic species and other violet species have additional descriptors such as himesumire or nojisumire. Its specific name is derived from Manchuria, an area of its native habitat which has at different times in history included parts of modern China, Korea, Mongolia and the Russian Far East.
Distribution
It is native to eastern Asia, being found as far west as eastern Siberia, throughout China, Taiwan and Korea, north into Russian North Asia (particularly in and around the Ussuri River Basin), and in much of Japan, including Okinawa. Across its range, this species occurs in a variety of habitats, from undisturbed woodlands to urban areas, and from low-lying plains to mountainous regions. A number of varieties have been developed by horticulturalists and are popular as garden plants. The wild form, and most named varieties and hybrids, prefer a semi-shaded location and humus-enriched soil that is not overly moist.
Description
Viola mandshurica, like many other viola species, does not have a true stem, with leaves and flowers each emerging directly from the ground (actually from its underground rhizome). Its rhizomatous roots are short and thick. The leaves are typically oval-lanceolate to lanceolate; while the color of the leaves is normally a medium green above and below, some cultivars, such as Fuji Dawn, have leaves variegated with white, yellow and/or pink spots, streaks or splotches.
As a violet, its trumpet-shaped flowers have five petals and bilateral symmetry. The lowermost petal is often the smallest, and all petals are typically a rich purple hue, though this can vary due to local conditions or localized mutations, and in some varieties deliberately bred for differing appearance.
Culi
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https://en.wikipedia.org/wiki/Coprine
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Coprine is a mycotoxin. It was first isolated from common inkcap (Coprinopsis atramentaria). It occurs in mushrooms in the genera Coprinopsis. When combined with alcohol, it causes "Coprinus syndrome". It inhibits the enzyme acetaldehyde dehydrogenase, which is involved in the metabolism of alcohol. This inhibition leads to a buildup of acetaldehyde, causing an alcohol flush reaction. Because of this, the mushroom is commonly referred to as Tippler's Bane.
History
Because of the similarities to disulfram (tetraethylthiuram disulfide) poisoning, it was long speculated that disulfram was the active ingredient in common inkcap. In 1956 it was reported that disulfram had been isolated from coprinus, but this finding could not be replicated. In 1975, coprine was identified as the compound in the common inkcap, with the mechanism identified in 1979.
Symptoms
Symptoms of coprine poisoning include facial reddening/flushing, nausea, vomiting, malaise, agitation, palpitations, tingling in limbs, and sometimes headache and excessive salivation. This can be described as the alcohol flush reaction. Symptoms typically arise five to ten minutes after consumption of alcohol. If no more alcohol is consumed, the symptoms will generally subside over two to three hours, and symptom severity is proportional to the amount of alcohol consumed. Consumption of alcohol can induce these symptoms for up to 5 days after ingesting coprine. Interestingly, symptoms of coprine poisoning do not appear when the mushroom is ingested raw, but only when the mushroom is cooked.
In examining coprine poisoning cases in Germany in 2010, none of the patients died, and all made full recoveries after abstaining from alcohol. In one case medical care was not sought at all, and while there was a range in time of ethanol consumption after mushroom consumption, all the cases had well-cooked the mushrooms before ingestion.
The symptoms of coprine poisoning and alcohol consumption are similar to those induce
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https://en.wikipedia.org/wiki/List%20of%20quasiparticles
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This is a list of quasiparticles.
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https://en.wikipedia.org/wiki/Simmons%E2%80%93Su%20protocols
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The Simmons–Su protocols are several protocols for envy-free division. They are based on Sperner's lemma. The merits of these protocols is that they put few restrictions on the preferences of the partners, and ask the partners only simple queries such as "which piece do you prefer?".
Protocols were developed for solving several related problems:
Cake cutting
In the envy-free cake-cutting problem, a "cake" (a heterogeneous divisible resource) has to be divided among n partners with different preferences over parts of the cake. The cake has to be divided to n pieces such that: (a) each partner receives a single connected piece, and (b) each partner believes that his piece is (weakly) better than all other pieces. A protocol for solving this problem was developed by Forest Simmons in 1980, in a correspondence with Michael Starbird. It was first publicized by Francis Su in 1999.
Given a cut-set (i.e. a certain partition of the cake to n pieces), we say that a partner prefers a given piece if he believes that this piece is weakly better than all other pieces. "Weakly" means that the partner may be indifferent between the piece and one or more other pieces, so he may (in case of ties) "prefer" more than one piece.
The protocol makes the following assumptions on the preferences of the partners:
Independence on other partners: The preference depends on the partner and the entire cut-set, but not on choices made by the other partners.
Hungry partners: Partners never prefer an empty piece.
Topologically closed preference sets: Any piece that is preferred for a convergent sequence of cut-sets, is preferred at the limiting cut-set. So for example, if a partner prefers the first piece in all cut-sets where the first cut is done at x > 0.2 and prefers the second piece in all cut-sets where the first cut is at x < 0.2, then at the cut-set where the first cut is at x = 0.2 that partner prefers both pieces equally.
The closedness condition rules out the existence of singl
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https://en.wikipedia.org/wiki/White%20meat
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In culinary terms, white meat is meat which is pale in color before and after cooking. In traditional gastronomy, white meat also includes rabbit, the flesh of milk-fed young mammals (in particular veal and lamb), and sometimes pork. In ecotrophology and nutritional studies, white meat includes poultry and fish, but excludes all mammal flesh, which is considered red meat.
Various factors have resulted in debate centering on the definition of white and red meat. Dark meat is used to describe darker-colored flesh. A common example is the lighter-colored meat of poultry (white meat), coming from the breast, as contrasted with darker-colored meat from the legs (dark meat). Certain types of poultry that are sometimes grouped as white meat are red when raw, such as duck and goose. Some types of fish, such as tuna, sometimes are red when raw and turn white when cooked.
Terminology
The terms white, red, light and dark applied to meat have varied and inconsistent meanings in different contexts. The term white meat in particular has caused confusion from oversimplification in scientific publications, misuse of the term in the popular press, and evolution of the term over decades. Some writers suggest avoiding the terms "red" and "white" altogether, instead classifying meat by objective characteristics such as myoglobin or heme iron content, lipid profile, fatty acid composition, cholesterol content, etc.
In nutritional studies, white meat may also include amphibians like frogs and land snails. Mammal flesh (eg; beef, pork, goat, lamb, doe, rabbit) is excluded and considered to be red meat. Periodically some researchers allow lean cuts of rabbit to be an outlier and categorize it into the “white meat” category because it shares certain nutritional similarities with poultry. Otherwise, nutritional studies and social studies popularly define "red meat" as coming from any mammal, "seafood" as coming from fish and shellfish, and "white meat" coming from birds and other animals.
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https://en.wikipedia.org/wiki/S-Video
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S-Video (also known as separate video, Y/C, and erroneously Super-Video) is an analog video signal format that carries standard-definition video, typically at 525 lines or 625 lines. It encodes video luma and chrominance on two separate channels, achieving higher image quality than composite video which encodes all video information on one channel. It also eliminates several types of visual defects such as dot crawl which commonly occur with composite video. Although it improved over composite video, S-Video has lower color resolution than component video, which is encoded over three channels.
The Atari 800 was the first to introduce separate Chroma/Luma output in late 1979. However, S-Video did not get widely adopted until JVC's introduction of the S-VHS (Super-VHS) format in 1987, which is why it is sometimes incorrectly referred to as Super-Video. Before the shift towards digital video the S-video format was widely used by consumers, but it was rarely used in professional studios where YPbPr or component was generally preferred.
Background
Standard analog television signals go through several processing steps on their way to being broadcast, each of which discards information and lowers the quality of the resulting images.
The image is originally captured in RGB form and then processed into three signals known as YPbPr. The first of these signals is called Y, which is created from all three original signals based on a formula that produces an overall brightness of the image, or luma. This signal closely matches a traditional black and white television signal and the Y/C method of encoding was key to offering backward compatibility. Once the Y signal is produced, it is subtracted from the blue signal to produce Pb and from the red signal to produce Pr. To recover the original RGB information for display, the signals are mixed with the Y to produce the original blue and red, and then the sum of those is mixed with the Y to recover the green.
A signal with thre
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https://en.wikipedia.org/wiki/Mathematical%20Foundations%20of%20Quantum%20Mechanics
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The book Mathematical Foundations of Quantum Mechanics (1932) by John von Neumann is an important early work in the development of quantum theory.
Publication history
The book was originally published in German in 1932 by Julius Springer, under the title .
An English translation by Robert T. Beyer was published in 1955 by Princeton University Press.
A Russian translation, edited by N. Bogolyubov, was published by Nauka in 1964.
A new English edition, edited by Nicholas A. Wheeler, was published in 2018 by Princeton University Press.
Significance
The book mainly summarizes results that von Neumann had published in earlier papers.
Its main significance may be its argument against the idea of hidden variables, on thermodynamic grounds.
See also
Mathematical formulation of quantum mechanics
Quantum Theory: Concepts and Methods
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https://en.wikipedia.org/wiki/Distribution%20frame
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In telecommunications, a distribution frame is a passive device which terminates cables, allowing arbitrary interconnections to be made.
For example, the Main Distribution Frame (MDF) located at a telephone central office terminates the cables leading to subscribers on the one hand, and cables leading to active equipment (such as DSLAMs and telephone switches) on the other. Service is provided to a subscriber by manually wiring a twisted pair (called a jumper wire) between the telephone line and the relevant DSL or POTS line circuit.
In broadcast engineering, a distribution frame is a location within an apparatus room through which all signals (audio, video, or data) pass, with the ability to arbitrarily route and connect sources and destinations between studios and other internal and external points. Connections can either be soldered, or made using terminal blocks. Because the frame may carry live broadcast signals, it may be considered part of the airchain.
In data communication, a building distribution frame (BDF) houses data switches, etc.
Types
Distribution frames for specific types of signals often have specific initialisms:
DDF—digital distribution frame
IDF—Intermediate distribution frame
MDF—Main distribution frame
ODF or OFDF—optical fiber distribution frame
VDF—voice distribution frame
Modernization
Distribution frames may grow to extremely large sizes. In major installations, audio distribution frames can have as many as 10,000 incoming and outgoing separate copper wires (balanced audio signals require two wires plus earth ground for each signal). Telephone signals do not use a separate earth ground wire, but some urban exchanges have about 250,000 wires on their MDF. Installing and rewiring these jumpers is a labour-intensive task, leading to attempts in the industry to devise so-called active distribution frames or Automated Main Distribution Frames. The principal issues which stand in the way of their widespread adoption are cost and relia
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https://en.wikipedia.org/wiki/Nojirimycin
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Nojirimycin is the parent compound of a class of antibiotics and glycosidase inhibitors. Nojirimycin and its derivatives are mainly obtained from a class of Streptomyces species. Chemically, it is an iminosugar.
Derivatives
1-deoxynojirimycin or duvoglustat
1-deoxygalactonojirimycin or migalastat, a drug for the treatment of Fabry disease
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https://en.wikipedia.org/wiki/Model%20lipid%20bilayer
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A model lipid bilayer is any bilayer assembled in vitro, as opposed to the bilayer of natural cell membranes or covering various sub-cellular structures like the nucleus. They are used to study the fundamental properties of biological membranes in a simplified and well-controlled environment, and increasingly in bottom-up synthetic biology for the construction of artificial cells. A model bilayer can be made with either synthetic or natural lipids. The simplest model systems contain only a single pure synthetic lipid. More physiologically relevant model bilayers can be made with mixtures of several synthetic or natural lipids.
There are many different types of model bilayers, each having experimental advantages and disadvantages. The first system developed was the black lipid membrane or “painted” bilayer, which allows simple electrical characterization of bilayers but is short-lived and can be difficult to work with. Supported bilayers are anchored to a solid substrate, increasing stability and allowing the use of characterization tools not possible in bulk solution. These advantages come at the cost of unwanted substrate interactions which can denature membrane proteins.
Black lipid membranes (BLM)
The earliest model bilayer system developed was the “painted” bilayer, also known as a “black lipid membrane.” The term “painted” refers to the process by which these bilayers are made. First, a small aperture is created in a thin layer of a hydrophobic material such as Teflon. Typically the diameter of this hole is a few tens of micrometers up to hundreds of micrometers. To form a BLM, the area around the aperture is first "pre-painted" with a solution of lipids dissolved in a hydrophobic solvent by applying this solution across the aperture with a brush, syringe, or glass applicator. The solvent used must have a very high partition coefficient and must be relatively viscous to prevent immediate rupture. The most common solvent used is a mixture of decane and squ
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https://en.wikipedia.org/wiki/Low-level%20laser%20therapy
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Low-level laser therapy (LLLT), cold laser therapy, photobiomodulation (PBM) or red light therapy is a form of medicine that applies low-level (low-power) lasers or light-emitting diodes (LEDs) to the surface of the body. Whereas high-power lasers are used in laser medicine to cut or destroy tissue, it is claimed that application of low-power lasers relieves pain or stimulates and enhances cell function. The effects appear to be limited to a specified set of wavelengths and new research has demonstrated effectiveness at myopia control. Several such devices are cleared by the United States Food and Drug Administration (FDA), and research shows potential for treating a range of medical problems including rheumatoid arthritis and oral mucositis.
Mechanism
Research is ongoing about the mechanism of LLLT. The effects of LLLT appear to be limited to a specified set of wavelengths of laser, and administering LLLT below the dose range does not appear to be effective. Photochemical reactions are well known in biological research, and LLLT make use of the first law in photochemistry (Grotthuss-Draper law): light must be absorbed by a chemical substance in order for a photochemical reaction to take place. In LLLT that chemical substance is represented by the respiratory enzyme cytochrome c oxidase which is involved in the electron transport chain in mitochondria, which is the generally accepted theory.
Medical uses
Various LLLT devices have been promoted for use in treatment of several musculoskeletal conditions including carpal tunnel syndrome (CTS), fibromyalgia, osteoarthritis, and rheumatoid arthritis. They have also been promoted for temporomandibular joint disorders, wound healing, smoking cessation, and tuberculosis. LLLT appears to be effective for preventing oral mucositis in recipients of a stem cell transplant with chemotherapy. In other areas, evidence for LLLT remains conflicted. Some studies suggest that LLLT may be modestly effective in relieving short-term
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https://en.wikipedia.org/wiki/Lesser%20omentum
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The lesser omentum (small omentum or gastrohepatic omentum) is the double layer of peritoneum that extends from the liver to the lesser curvature of the stomach, and to the first part of the duodenum. The lesser omentum is usually divided into these two connecting parts: the hepatogastric ligament, and the hepatoduodenal ligament.
Structure
The lesser omentum is extremely thin, and is continuous with the two layers of peritoneum which cover respectively the antero-superior and postero-inferior surfaces of the stomach and first part of the duodenum.
When these two layers reach the lesser curvature of the stomach and the upper border of the duodenum, they join and ascend as a double fold to the porta hepatis.
To the left of the porta, the fold is attached to the bottom of the fossa for the ductus venosus, along which it is carried to the diaphragm, where the two layers separate to embrace the end of the esophagus.
At the right border of the lesser omentum, the two layers are continuous, and form a free margin which constitutes the anterior boundary of the omental foramen.
Divisions
Anatomically, the lesser omentum is divided into ligaments, each starting with the prefix "hepato" to indicate that it connects to the liver at one end.
Most sources divide it into two parts:
hepatogastric ligament: the portion connecting to the lesser curvature of the stomach
hepatoduodenal ligament: the portion connecting to the duodenum
In some cases, the following ligaments are considered part of the lesser omentum:
hepatophrenic ligament: the portion connecting to the thoracic diaphragm
hepatoesophageal ligament: the portion connecting to the esophagus
hepatocolic ligament: the portion connecting to the colon
Contents
Between the two layers of the lesser omentum, close to the right free margin, are the hepatic artery proper, the common bile duct, the portal vein, lymphatics, and the hepatic plexus of nerves—all these structures being enclosed in a fibrous capsule (Glis
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https://en.wikipedia.org/wiki/EFI%20system%20partition
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The EFI (Extensible Firmware Interface) system partition or ESP is a partition on a data storage device (usually a hard disk drive or solid-state drive) that is used by computers having the Unified Extensible Firmware Interface (UEFI). When a computer is booted, UEFI firmware loads files stored on the ESP to start installing operating systems and various utilities.
An ESP contains the boot loaders or kernel images for all installed operating systems (which are contained in other partitions), device driver files for hardware devices present in a computer and used by the firmware at boot time, system utility programs that are intended to be run before an operating system is booted, and data files such as error logs.
Overview
The EFI system partition is formatted with a file system whose specification is based on the FAT file system and maintained as part of the UEFI specification; therefore, the file system specification is independent from the original FAT specification. The actual extent of divergence is unknown: Apple maintains a separate tool that should be used, while other systems use FAT utilities just fine. The globally unique identifier (GUID) for the EFI system partition in the GUID Partition Table (GPT) scheme is , while its ID in the master boot record (MBR) partition-table scheme is . Both GPT- and MBR-partitioned disks can contain an EFI system partition, as UEFI firmware is required to support both partitioning schemes. Also, El Torito bootable format for CD-ROMs and DVDs is supported.
UEFI provides backward compatibility with legacy systems by reserving the first block (sector) of the partition for compatibility code, effectively creating a legacy boot sector. On legacy BIOS-based systems, the first sector of a partition is loaded into memory, and execution is transferred to this code. UEFI firmware does not execute the code in the MBR, except when booting in legacy BIOS mode through the Compatibility Support Module (CSM).
The UEFI specification
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https://en.wikipedia.org/wiki/Timeline%20of%20number%20theory
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A timeline of number theory.
Before 1000 BCE
ca. 20,000 BCE — Nile Valley, Ishango Bone: possibly the earliest reference to prime numbers and Egyptian multiplication although this is disputed.
About 300 BCE
300 BCE — Euclid proves the number of prime numbers is infinite.
1st millennium AD
250 — Diophantus writes Arithmetica, one of the earliest treatises on algebra.
500 — Aryabhata solves the general linear diophantine equation.
628 - Brahmagupta gives Brahmagupta's identity and solves the so called Pell's equation using his composition method.
ca. 650 — Mathematicians in India create the Hindu–Arabic numeral system we use, including the zero, the decimals and negative numbers.
1000–1500
ca. 1000 — Abu-Mahmud al-Khujandi first states a special case of Fermat's Last Theorem.
895 — Thabit ibn Qurra gives a theorem by which pairs of amicable numbers can be found, (i.e., two numbers such that each is the sum of the proper divisors of the other).
975 — The earliest triangle of binomial coefficients (Pascal triangle) occur in the 10th century in commentaries on the Chandas Shastra.
1150 — Bhaskara II gives first general method for solving Pell's equation
1260 — Al-Farisi gave a new proof of Thābit ibn Qurra's theorem, introducing important new ideas concerning factorization and combinatorial methods. He also gave the pair of amicable numbers 17296 and 18416 which have also been jointly attributed to Fermat as well as Thabit ibn Qurra.
17th century
1637 — Pierre de Fermat claims to have proven Fermat's Last Theorem in his copy of Diophantus' Arithmetica.
18th century
1742 — Christian Goldbach conjectures that every even number greater than two can be expressed as the sum of two primes, now known as Goldbach's conjecture.
1770 — Joseph Louis Lagrange proves the four-square theorem, that every positive integer is the sum of four squares of integers. In the same year, Edward Waring conjectures Waring's problem, that for any positive integer k, every posit
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https://en.wikipedia.org/wiki/Adiabatic%20electron%20transfer
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Adiabatic electron-transfer is a type of oxidation-reduction processes. The mechanism is ubiquitous in nature in both the inorganic and biological spheres. Adiabatic electron-transfers proceed without making or breaking chemical bonds. Adiabatic electron-transfer can occur by either optical or thermal mechanisms. Electron transfer during a collision between an oxidant and a reductant occurs adiabatically on a continuous potential-energy surface.
History
Noel Hush is often credited with formulation of the theory of adiabatic electron-transfer.
Figure 1 sketches the basic elements of adiabatic electron-transfer theory. Two chemical species (ions, molecules, polymers, protein cofactors, etc.) labelled D (for “donor”) and A (for “acceptor”) become a distance R apart, either through collisions, covalent bonding, location in a material, protein or polymer structure, etc. A and D have different chemical environments. Each polarizes their surrounding condensed media. Electron-transfer theories describe the influence of a variety of parameters on the rate of electron-transfer. All electrochemical reactions occur by this mechanism. Adiabatic electron-transfer theory stresses that intricately coupled to such charge transfer is the ability of any D-A system to absorb or emit light. Hence fundamental understanding of any electrochemical process demands simultaneous understanding of the optical processes that the system can undergo.
Figure 2 sketches what happens if light is absorbed by just one of the chemical species, taken to be the charge donor. This produces an excited state of the donor. As the donor and acceptor are close to each other and surrounding matter, they experience a coupling . If the free energy change is favorable, this coupling facilitates primary charge separation to produce D+-A− , producing charged species. In this way, solar energy is captured and converted to electrical energy. This process is typical of natural photosynthesis as well as modern o
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https://en.wikipedia.org/wiki/Lanczos%20resampling
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Lanczos filtering and Lanczos resampling are two applications of a mathematical formula. It can be used as a low-pass filter or used to smoothly interpolate the value of a digital signal between its samples. In the latter case, it maps each sample of the given signal to a translated and scaled copy of the Lanczos kernel, which is a sinc function windowed by the central lobe of a second, longer, sinc function. The sum of these translated and scaled kernels is then evaluated at the desired points.
Lanczos resampling is typically used to increase the sampling rate of a digital signal, or to shift it by a fraction of the sampling interval. It is often used also for multivariate interpolation, for example to resize or rotate a digital image. It has been considered the "best compromise" among several simple filters for this purpose.
The filter is named after its inventor, Cornelius Lanczos ().
Definition
Lanczos kernel
The effect of each input sample on the interpolated values is defined by the filter's reconstruction kernel , called the Lanczos kernel. It is the normalized sinc function , windowed (multiplied) by the Lanczos window, or sinc window, which is the central lobe of a horizontally stretched sinc function for .
Equivalently,
The parameter is a positive integer, typically 2 or 3, which determines the size of the kernel. The Lanczos kernel has lobes: a positive one at the center, and alternating negative and positive lobes on each side.
Interpolation formula
Given a one-dimensional signal with samples , for integer values of , the value interpolated at an arbitrary real argument is obtained by the discrete convolution of those samples with the Lanczos kernel:
where is the filter size parameter, and is the floor function. The bounds of this sum are such that the kernel is zero outside of them.
Properties
As long as the parameter is a positive integer, the Lanczos kernel is continuous everywhere, and its derivative is defined and con
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https://en.wikipedia.org/wiki/Content%20ID
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Content-ID may refer to:
Content ID (system), a digital fingerprinting system used to identify and manage copyrighted content on YouTube
URI scheme (cid:), allows the use of MIME within email
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https://en.wikipedia.org/wiki/Marchenko%E2%80%93Pastur%20distribution
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In the mathematical theory of random matrices, the Marchenko–Pastur distribution, or Marchenko–Pastur law, describes the asymptotic behavior of singular values of large rectangular random matrices. The theorem is named after Soviet mathematicians Vladimir Marchenko and Leonid Pastur who proved this result in 1967.
If denotes a random matrix whose entries are independent identically distributed random variables with mean 0 and variance , let
and let be the eigenvalues of (viewed as random variables). Finally, consider the random measure
counting the number of eigenvalues in the subset included in .
Theorem. Assume that so that the ratio . Then (in weak* topology in distribution), where
and
with
The Marchenko–Pastur law also arises as the free Poisson law in free probability theory, having rate and jump size .
Cumulative distribution function
Using the same notation, cumulative distribution function reads
where
and .
Moments
For each , its -th moment is
Some transforms of this law
The Cauchy transform (which is the negative of the Stieltjes transformation) is given by
Voiculescu's -transform is given by
and the -transform by
Application to correlation matrices
For the special case of correlation matrices, we know that
and . This bounds the probability mass over the interval defined by
Since this distribution describes the spectrum of random matrices with mean 0, the eigenvalues of correlation matrices that fall inside of the aforementioned interval could be considered spurious or noise. For instance, obtaining a correlation matrix of 10 stock returns calculated over a 252 trading days period would render . Thus, out of 10 eigenvalues of said correlation matrix, only the values higher than 1.43 would be considered significantly different from random.
See also
Wigner semicircle distribution
Tracy–Widom distribution
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https://en.wikipedia.org/wiki/105th%20meridian%20east
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The meridian 105° east of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, Asia, the Indian Ocean, the Southern Ocean, and Antarctica to the South Pole. Under mean solar time represents the offset of UTC+07:00 time zone.
The 105th meridian east forms a great circle with the 75th meridian west.
From Pole to Pole
Starting at the North Pole and heading south to the South Pole, the 105th meridian east passes through:
{| class="wikitable plainrowheaders"
! scope="col" width="130" | Co-ordinates
! scope="col" | Country, territory or sea
! scope="col" | Notes
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| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Arctic Ocean
| style="background:#b0e0e6;" |
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| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Laptev Sea
| style="background:#b0e0e6;" |
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! scope="row" |
| Krasnoyarsk Krai — Bolshevik Island, Severnaya Zemlya
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| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Laptev Sea
| style="background:#b0e0e6;" |
|-valign="top"
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! scope="row" |
| Krasnoyarsk Krai Irkutsk Oblast — from Krasnoyarsk Krai — from Irkutsk Oblast — from Krasnoyarsk Krai — from Irkutsk Oblast — from Krasnoyarsk Krai — from Irkutsk Oblast — from Republic of Buryatia — from (border is in Lake Baikal)
|-
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! scope="row" |
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|-valign="top"
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! scope="row" |
| Inner Mongolia Ningxia – from Gansu – from Sichuan – from Yunnan – from Guizhou – from Guangxi – from Yunnan – from
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! scope="row" |
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! scope="row" |
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! scope="row" |
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|-
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! scope="row" |
|Passing just east of Phnom Penh (at )
|-
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! scope="row" |
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|-valign="top"
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | South China Sea
| style="background:#b0e0e6;" | Passing just east of Lingga Island, (at ) Passing just west of Bangka Island, (at )
|-
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! scope="row" |
| Island of Sumatra
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https://en.wikipedia.org/wiki/Atmospheric%20escape
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Atmospheric escape is the loss of planetary atmospheric gases to outer space. A number of different mechanisms can be responsible for atmospheric escape; these processes can be divided into thermal escape, non-thermal (or suprathermal) escape, and impact erosion. The relative importance of each loss process depends on the planet's escape velocity, its atmosphere composition, and its distance from its star. Escape occurs when molecular kinetic energy overcomes gravitational energy; in other words, a molecule can escape when it is moving faster than the escape velocity of its planet. Categorizing the rate of atmospheric escape in exoplanets is necessary to determining whether an atmosphere persists, and so the exoplanet's habitability and likelihood of life.
Thermal escape mechanisms
Thermal escape occurs if the molecular velocity due to thermal energy is sufficiently high. Thermal escape happens at all scales, from the molecular level (Jeans escape) to bulk atmospheric outflow (hydrodynamic escape).
Jeans escape
One classical thermal escape mechanism is Jeans escape, named after British astronomer Sir James Jeans, who first described this process of atmospheric loss. In a quantity of gas, the average velocity of any one molecule is measured by the gas's temperature, but the velocities of individual molecules change as they collide with one another, gaining and losing kinetic energy. The variation in kinetic energy among the molecules is described by the Maxwell distribution. The kinetic energy (), mass (), and velocity () of a molecule are related by . Individual molecules in the high tail of the distribution (where a few particles have much higher speeds than the average) may reach escape velocity and leave the atmosphere, provided they can escape before undergoing another collision; this happens predominantly in the exosphere, where the mean free path is comparable in length to the pressure scale height. The number of particles able to escape depends on the mol
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https://en.wikipedia.org/wiki/Delaware%20Biotechnology%20Institute
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The Delaware Biotechnology Institute (DBI) at the University of Delaware is a partnership among government, academia and industry with an aim to establish Delaware as a notable hub for biotechnology and life sciences.
Adjacent to the University of Delaware main campus, DBI's research facility is located in the Delaware Technology Park. The DBI laboratory houses more than 180 faculty and students.
Research at the Delaware Biotechnology Institute has application in agriculture, environmental science, and human health, featuring leading-edge work in bioinformatics, genomics and small RNA biology, materials science, molecular medicine and proteomics.
Partner Institutions
University of Delaware
Delaware State University
Delaware Technical & Community College
Wesley College
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https://en.wikipedia.org/wiki/Cercopithecine%20alphaherpesvirus%209
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Cercopithecine alphaherpesvirus 9 (CeHV-9) is a species of virus in the genus Varicellovirus, subfamily Alphaherpesvirinae, family Herpesviridae, and order Herpesvirales.
Pathology
Cercopithecine alphaherpesvirus 9 infects primates and shares clinical, pathological, immunological, and virological features with varicella-zoster virus infection of humans. Monkeys that had been inoculated intratracheally with the virus developed diffuse varicella 10 to 12 days later. Monkeys that were caged with each of the intratracheally infected monkeys developed a mild rash two weeks later, hence providing evidence of airborne transmission.
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https://en.wikipedia.org/wiki/Concolic%20testing
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Concolic testing (a portmanteau of concrete and symbolic, also known as dynamic symbolic execution) is a hybrid software verification technique that performs symbolic execution, a classical technique that treats program variables as symbolic variables, along a concrete execution (testing on particular inputs) path. Symbolic execution is used in conjunction with an automated theorem prover or constraint solver based on constraint logic programming to generate new concrete inputs (test cases) with the aim of maximizing code coverage. Its main focus is finding bugs in real-world software, rather than demonstrating program correctness.
A description and discussion of the concept was introduced in "DART: Directed Automated Random Testing" by Patrice Godefroid, Nils Klarlund, and Koushik Sen. The paper "CUTE: A concolic unit testing engine for C", by Koushik Sen, Darko Marinov, and Gul Agha, further extended the idea to data structures, and first coined the term concolic testing. Another tool, called EGT (renamed to EXE and later improved and renamed to KLEE), based on similar ideas was independently developed by Cristian Cadar and Dawson Engler in 2005, and published in 2005 and 2006. PathCrawler first proposed to perform symbolic execution along a concrete execution path, but unlike concolic testing PathCrawler does not simplify complex symbolic constraints using concrete values. These tools (DART and CUTE, EXE) applied concolic testing to unit testing of C programs and concolic testing was originally conceived as a white box improvement upon established random testing methodologies. The technique was later generalized to testing multithreaded Java programs with , and unit testing programs from their executable codes (tool OSMOSE). It was also combined with fuzz testing and extended to detect exploitable security issues in large-scale x86 binaries by Microsoft Research's SAGE.
The concolic approach is also applicable to model checking. In a concolic model checker, the
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https://en.wikipedia.org/wiki/Polycystin%201
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Polycystin 1 (PC1) is a protein that in humans is encoded by the PKD1 gene. Mutations of PKD1 are associated with most cases of autosomal dominant polycystic kidney disease, a severe hereditary disorder of the kidneys characterised by the development of renal cysts and severe kidney dysfunction.
Protein structure and function
PC1 is a membrane-bound protein 4303 amino acids in length expressed largely upon the primary cilium, as well as apical membranes, adherens junctions, and desmosomes. It has 11 transmembrane domains, a large extracellular N-terminal domain, and a short (about 200 amino acid) cytoplasmic C-terminal domain. This intracellular domain contains a coiled-coil domain through which PC1 interacts with polycystin 2 (PC2), a membrane-bound Ca2+-permeable ion channel.
PC1 has been proposed to act as a G protein–coupled receptor. The C-terminal domain may be cleaved in a number of different ways. In one instance, a ~35 kDa portion of the tail has been found to accumulate in the cell nucleus in response to decreased fluid flow in the mouse kidney. In another instance, a 15 kDa fragment may be yielded, interacting with transcriptional activator and co-activator STAT6 and p100, or components of the canonical Wnt signaling pathway in an inhibitory manner.
The structure of the human PKD1-PKD2 complex has been solved by cryo-electron microscopy, which showed a 1:3 ratio of PKD1 and PKD2 in the structure. PKD1 consists of a voltage-gated ion channel fold that interacts with PKD2.
PC1 mediates mechanosensation of fluid flow by the primary cilium in the renal epithelium and of mechanical deformation of articular cartilage.
Gene
Splice variants encoding different isoforms have been noted for PKD1. The gene is closely linked to six pseudogenes in a known duplicated region on chromosome 16p.
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https://en.wikipedia.org/wiki/Southern%20Ocean%20Observing%20System
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Southern Ocean Observing System (SOOS) is an international initiative of the Scientific Committee on Antarctic Research (SCAR) and the Scientific Committee on Oceanic Research (SCOR). It was officially launched in 2011. Its International Project Office is hosted by the Institute for Marine and Antarctic Studies (IMAS), University of Tasmania, Australia.
The Southern Ocean comprises the southernmost waters of the World Ocean, generally taken to be south of 60° S latitude and encircling Antarctica. As such, it is regarded as the second-smallest of the five principal oceanic divisions: smaller than the Pacific, Atlantic, and Indian oceans but larger than the Arctic Ocean. Over the past 30 years, the Southern Ocean has been subject to rapid climate change, which has led to changes in the marine ecosystem.
SOOS is designed to aid the collection and delivery of essential observations on dynamics and change of Southern Ocean systems to all international stakeholders (researchers, governments, industries). It seeks to enable the design, advocacy and implementation of cost-effective observing and data delivery systems.
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https://en.wikipedia.org/wiki/Nivalenol
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Nivalenol (NIV) is a mycotoxin of the trichothecene group. In nature it is mainly found in fungi of the Fusarium species. The Fusarium species belongs to the most prevalent mycotoxin producing fungi in the temperate regions of the northern hemisphere, therefore making them a considerable risk for the food crop production industry.
The fungi are abundant in various agricultural products (cereal crops) and their further processed products (malt, beer and bread). "The Fusarium species invade and grow on crops, and may produce nivalenol under moist and cool conditions".
In pigs, the symptoms observed after nivalenol exposure are "feed refusal, vomiting, gastroenteric and dermal irritation or necrosis and immunological dysfunction", as well as haematotoxicity, resulting in a low leukocyte count.
History
In the period of 1946-1963 several cases of intoxication due to the ingestion of Fusarium infected grains (Scrabby grain disease) were reported in Japan, Korea and India. There have been no reports of lethal cases and only mild symptoms like nausea, vomiting, diarrhea and abdominal pain. In these incidents F.graminaerum could be isolated which hints at a nivalenol or deoxynivalenol contamination.
In the same period two outbreaks involving over 100 cases were reported in India and China. These outbreaks were also non-lethal.
A well documented and acute outbreak in India in 1987 affected around 50,000 thousand people. Several Fusarium toxins under which nivalenol (0.03–0.1 mg/kg in 2 of 24 samples), deoxynivalenol (0.34–8.4 mg/kg in 11 of 24 samples) and acetyldeoxynivalenol (0.6–2.4 mg/kg in 4 of 24 samples) were found in rain-damaged wheat used for bread production. There were again no lethal cases and reported symptoms were abdominal pain, diarrhea, bloody stool and vomiting. These cases show that the main emerging danger of nivalenol comes from Fusarium infected cereals and is mainly via the route of digestion of uncontrolled wheat or other grains which is furthe
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https://en.wikipedia.org/wiki/Harish-Chandra%27s%20%CE%9E%20function
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In mathematical harmonic analysis, Harish-Chandra's Ξ function is a special spherical function on a semisimple Lie group, studied by .
Harish-Chandra used it to define Harish-Chandra's Schwartz space.
gives a detailed description of the properties of Ξ.
Definition
where
K is a maximal compact subgroup of a semisimple Lie group with Iwasawa decomposition G=NAK
g is an element of G
ρ is a Weyl vector
a(g) is the element a in the Iwasawa decomposition g=nak
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https://en.wikipedia.org/wiki/Oven%20temperatures
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Common oven temperatures (such as terms: cool oven, very slow oven, slow oven, moderate oven, hot oven, fast oven, etc.) are set to control the effects of baking in an oven, for various lengths of time.
Standard phrases
{| class=wikitable style="float:right; margin-left:1em"
|-
! colspan=3 style="background-color:#F1CC66;" | Table of equivalent oven temperatures
|-
! Description || °F || °C
|-
| Cool oven || 200 °F || 90 °C
|-
| Very slow oven || 250 °F || 120 °C
|-
| Slow oven || 300–325 °F || 150–160 °C
|-
| Moderately slow || 325–350 °F || 160–180 °C
|-
| Moderate oven || 350–375 °F || 180–190 °C
|-
| Moderately hot || 375–400 °F || 190–200 °C
|-
| Hot oven || 400–450 °F || 200–230 °C
|-
| Very hot oven || 450–500 °F || 230–260 °C
|-
| Fast oven || 450–500 °F || 230–260 °C
|}
The various standard phrases, to describe oven temperatures, include words such as "cool" to "hot" or "very slow" to "fast". For example, a cool oven has temperature set to 200 °F (90 °C), and a slow oven has a temperature range from 300–325 °F (150–160 °C). A moderate oven has a range of 350–375 °F (180–190 °C), and a hot oven has temperature set to 400–450 °F (200–230 °C). A fast oven has a range of 450-500 °F (230–260 °C) for the typical temperature.
Estimating oven temperature
Before ovens had thermometers or thermostats, these standard words were used by cooks and cookbooks to describe how hot an oven should be to cook various items. Custards require a slow oven for example, bread a moderate oven, and pastries a very hot oven. Cooks estimated the temperature of an oven by counting the number of minutes it took to turn a piece of white paper golden brown, or counting the number of seconds one could hold one's hand in the oven. Another method was to put a layer of flour or a piece of white tissue paper on a pan in the oven for five minutes. The resulting colors range from delicate brown in a slow oven through golden brown in a modera
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https://en.wikipedia.org/wiki/Rundlet
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The rundlet is an archaic unit-like size of wine casks once used in Britain. It was equivalent to about 68 litres. It used to be defined as 18 wine gallons—one of several gallons then in use—before the adoption of the imperial system in 1824, afterwards it was 15 imperial gallons, which became the universal English base unit of volume in the British realm.
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https://en.wikipedia.org/wiki/Thallophyca
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Thallophyca is a non-mineralized Ediacarian alga that probably dwelt on the sea floor. Its thallus is differentiated into a cortex and a medulla. Possible reproductive structures have been identified.
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https://en.wikipedia.org/wiki/Micro%20heat%20exchanger
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Micro heat exchangers, Micro-scale heat exchangers, or microstructured heat exchangers are heat exchangers in which (at least one) fluid flows in lateral confinements with typical dimensions below 1 mm. The most typical such confinement are microchannels, which are channels with a hydraulic diameter below 1 mm. Microchannel heat exchangers can be made from metal or ceramic.
Microchannel heat exchangers can be used for many applications including:
high-performance aircraft gas turbine engines
heat pumps
Microprocessor and microchip cooling
air conditioning
Background
Investigation of microscale thermal devices is motivated by the single phase internal flow correlation for convective heat transfer:
Where is the heat transfer coefficient, is the Nusselt number, is the thermal conductivity of the fluid and is the hydraulic diameter of the channel or duct. In internal laminar flows, the Nusselt number becomes a constant. This is a result which can be arrived at analytically: For the case of a constant wall temperature, and for the case of constant heat flux for round tubes. The last value is increased to 140/17 = 8.23 for flat parallel plates. As Reynolds number is proportional to hydraulic diameter, fluid flow in channels of small hydraulic diameter will predominantly be laminar in character. This correlation therefore indicates that the heat transfer coefficient increases as channel diameter decreases. Should the hydraulic diameter in forced convection be on the order of tens or hundreds of micrometres, an extremely high heat transfer coefficient should result.
This hypothesis was initially investigated by Tuckerman and Pease. Their positive results led to further research ranging from classical investigations of single channel heat transfer to more applied investigations in parallel micro-channel and micro scale plate fin heat exchangers. Recent work in the field has focused on the potential of two-phase flows at the micro-scale.
Classification of mic
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https://en.wikipedia.org/wiki/TechnoSphere%20%28virtual%20environment%29
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TechnoSphere was an online digital environment launched on September 1, 1995 and hosted on a computer at a UK university. Created by Jane Prophet and Dr. Gordon Selley, TechnoSphere was a place where users from around the globe could create creatures and release them into the 3D environment, described by the creators as a "digital ecology." Earlier incarnations of TechnoSphere did not have the advantage of web-accessible 3D graphics, but was still governed by chaos theory and similar algorithms that determined each creature's unique behavior based on their components and interactions with each other and their environment.
The online program was one of many digital artificial life simulations that evolved as the World Wide Web began to grow. Many museums and classrooms found the tool to be a valuable complement to learning material on natural selection and ecosystems. The experiment operated online until 2002. It was relaunched on January 15, 2007, but became offline again as of November 2012.
Description
TechnoSphere was a real-time, 3D simulation of an environment that was populated by virtual creatures. Users across the globe had the capability to create their own creatures through a website. TechnoSphere III, one of many incarnations of the original design, used an artificial life program and fractal landscapes, which were governed by a complex set of rules and algorithms that determined how the virtual ecosystem reacted. The program was capable of modeling such concepts as simple evolution and carrying capacity. Despite limited available creature designs, no two would ever behave in the same way, due to chance interactions with its environment and other creatures.
Physically, the virtual landscape of TechnoSphere consisted of 16 km2 of terrain. It was capable of supporting approximately 4,000 creatures, though other sources suggest that as many as 20,000 creatures typically would coexist in the virtual environment at one time. After the relaunch, it was expl
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https://en.wikipedia.org/wiki/Circumference
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In geometry, the circumference (from Latin circumferens, meaning "carrying around") is the perimeter of a circle or ellipse. The circumference is the arc length of the circle, as if it were opened up and straightened out to a line segment. More generally, the perimeter is the curve length around any closed figure.
Circumference may also refer to the circle itself, that is, the locus corresponding to the edge of a disk.
The is the circumference, or length, of any one of its great circles.
Circle
The circumference of a circle is the distance around it, but if, as in many elementary treatments, distance is defined in terms of straight lines, this cannot be used as a definition. Under these circumstances, the circumference of a circle may be defined as the limit of the perimeters of inscribed regular polygons as the number of sides increases without bound. The term circumference is used when measuring physical objects, as well as when considering abstract geometric forms.
Relationship with
The circumference of a circle is related to one of the most important mathematical constants. This constant, pi, is represented by the Greek letter The first few decimal digits of the numerical value of are 3.141592653589793 ... Pi is defined as the ratio of a circle's circumference to its diameter
Or, equivalently, as the ratio of the circumference to twice the radius. The above formula can be rearranged to solve for the circumference:
The ratio of the circle's circumference to its radius is called the circle constant, and is equivalent to . The value is also the amount of radians in one turn. The use of the mathematical constant is ubiquitous in mathematics, engineering, and science.
In Measurement of a Circle written circa 250 BCE, Archimedes showed that this ratio ( since he did not use the name ) was greater than 3 but less than 3 by calculating the perimeters of an inscribed and a circumscribed regular polygon of 96 sides. This method for approximating was used
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https://en.wikipedia.org/wiki/Qin%20Jiushao
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Qin Jiushao (, ca. 1202–1261), courtesy name Daogu (道古), was a Chinese mathematician, meteorologist, inventor, politician, and writer. He is credited for discovering Horner's method as well as inventing Tianchi basins, a type of rain gauge instrument used to gather meteorological data.
Biography
Although Qin Jiushao was born in Ziyang, Sichuan, his family came from Shandong province. He is regarded as one of the greatest mathematicians in Chinese history. This is especially remarkable because Qin did not devote his life to mathematics. He was accomplished in many other fields and held a series of bureaucratic positions in several Chinese provinces.
Qin wrote Shùshū Jiǔzhāng ("Mathematical Treatise in Nine Sections") in 1247 CE. This treatise covered a variety of topics including indeterminate equations and the numerical solution of certain polynomial equations up to 10th order, as well as discussions on military matters and surveying. In the treatise Qin included a general form of the Chinese remainder theorem that used Da yan shu (大衍术) or algorithms to solve it. In geometry, he discovered "Qin Jiushao's formula" for finding the area of a triangle from the given lengths of three sides. This formula is the same as Heron's formula, proved by Heron of Alexandria about 60 BCE, though knowledge of the formula may go back to Archimedes.
As precipitation was important agriculture and food production, Qin developed precipitation gauges that was widely used in 1247 during the Mongol Empire/Southern Song dynasty to gather meteorological data. Qin Jiushao later records the application of rainfall measurements in the mathematical treatise. The book also discusses the use of large snow gauges made from bamboo situated in mountain passes and uplands which are speculated to be first referenced to snow measurement.
Qin recorded the earliest explanation of how Chinese calendar experts calculated astronomical data according to the timing of the winter solstice. Among his acc
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https://en.wikipedia.org/wiki/H%C3%BCtte
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The (originally , stylized as "HÜTTE" and pronounced ) is a reference work for engineers of various disciplines. It was compiled for the first time in 1857 by the (short , translating as "the hut") of the in Berlin, from which the association of German engineers Verein Deutscher Ingenieure (VDI) emerged. The authors were members of the association. The technical illustrations were created in woodcut technique by . It is published in constantly revised editions to this day and is therefore the oldest German reference work still available today.
First edition 1857 and bibliophile reprint 2007
The book was initially divided into three sections: (Mathematics and Mechanics), (Mechanical Engineering and Technology) and (Building Science) and was originally published by the publishing house , the later , who published it until 1971.
For the 150th anniversary in 2007, the first edition was reissued as a bibliophile reprint.
Historical development
Starting with the first edition in 1857, further book series have been developed over the decades. The reference work quickly developed into a standard work for engineers and was frequently reprinted and translated into other languages due to the great demand. The first translation ever was into Russian in 1863. In 1890, the work was divided into two, in 1908 into three, and finally in 1922 into four volumes. With the 27th edition in 1949, volume four was no longer available.
An English version was published by McGraw-Hill Book Co., New York, in 1916 as "Mechanical engineers' handbook, based on the Hütte and prepared by a staff of specialists" edited by Lionel Simeon Marks. This led to Marks' Standard Handbook for Mechanical Engineers, a work, which spawn several translations on its own and is continued up to the present with its 100th anniversary 12th edition published in 2017.
Another work initially influenced by the 1936 Russian translation of the 1931 edition of Hütte is the so called Bronshtein and Semendyayev (
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https://en.wikipedia.org/wiki/Lincoln%20index
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The Lincoln index is a statistical measure used in several fields to estimate the population size of an animal species. Described by Frederick Charles Lincoln in 1930, it is also sometimes known as the Lincoln-Petersen method after C.G. Johannes Petersen who was the first to use the related mark and recapture method.
Applications
Consider two observers who separately count the different species of plants or animals in a given area. If they each come back having found 100 species but only 5 particular species are found by both observers, then each observer clearly missed at least 95 species (that is, the 95 that only the other observer found). Thus, we know that both observers miss a lot. On the other hand, if 99 of the 100 species each observer found had been found by both, it is fair to expect that they have found a far higher percentage of the total species that are there to find.
The same reasoning applies to mark and recapture. If some animals in a given area are caught and marked, and later a second round of captures is done: the number of marked animals found in the second round can be used to generate an estimate of the total population.
Another example arises in computational linguistics for estimating the total vocabulary of a language. Given two independent samples, the overlap between their vocabularies enables a useful estimate of how many more vocabulary items exist but did not happen to show up in either sample. A similar example involves estimating the number of typographical errors remaining in a text, from two proofreaders' counts.
Formulation
The Lincoln Index formalizes this phenomenon. If E1 and E2 are the number of species (or words, or other phenomena) observed by two independent methods, and S is the number of observations in common, then the Lincoln Index is simply
For values of S < 10, this estimate is rough, and becomes extremely rough for values of S < 5. In the case where S = 0 (that is, there is no overlap at all) the Lincoln I
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https://en.wikipedia.org/wiki/Le%20Chat
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Le Chat (Le Cat in English-language editions) is a Belgian comic strip, created by Philippe Geluck. Foremost published daily in the newspaper Le Soir from March 22, 1983, until March 23, 2013, it is since issued directly as complete albums.
Right from the start, it quickly became one of the bestselling Franco-Belgian comics series and the mascot of Le Soir. While virtually an icon in Francophone Belgium, he is far less well known in Flanders.
Concept
Le Chat is an adult, human-sized obese, anthropomorphic cat who typically wears a suit. He always has the same physical expression. He often comes up with elaborate reasonings which lead to hilariously absurd conclusions e.g. by taking metaphors literally or by adding increasingly unlikely what-ifs to ordinary situations.
One page in length, it appeared weekly in the "Victor" supplement of Belgian newspaper Le Soir. For Le Chat's 20th anniversary in 2003, Le Soir allowed Geluck to illustrate that day's entire newspaper. An exhibition of Le Chat's history (and that of his creator), "Le Chat s'expose", was first held at the Autoworld Motor Museum in Brussels in Spring 2004, and has since toured Europe. In March–October 2006 it appeared at Les Champs Libres in Rennes.
In popular culture
As part of the Brussels' Comic Book Route a wall in the Zuidlaan/Boulevard du Midi in Brussels was dedicated to "Le Chat" in August 1993.
On October 11, 2008, Le Chat received his own market place in Hotton in the Belgian province Luxembourg. A statue of him, sculpted by François Deboucq, was placed in the center, depicting him holding an umbrella which rains water down from inside.
In 2015, "Le Chat" received his own museum.
Bibliography
Le Chat, 2001
Le Retour du Chat, 2001
La Vengeance du Chat, 2002
Le Quatrième Chat, 2002
Le Chat au Congo, 2003
Ma langue au Chat, 2004
Le Chat à Malibu, 2005
Le Chat 1999,9999, 1999
L'Avenir du Chat, 1999
Le Chat est content, 2000
L'Affaire le Chat, 2001 (Available in English as "The
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https://en.wikipedia.org/wiki/Relaxation%20%28approximation%29
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In mathematical optimization and related fields, relaxation is a modeling strategy. A relaxation is an approximation of a difficult problem by a nearby problem that is easier to solve. A solution of the relaxed problem provides information about the original problem.
For example, a linear programming relaxation of an integer programming problem removes the integrality constraint and so allows non-integer rational solutions. A Lagrangian relaxation of a complicated problem in combinatorial optimization penalizes violations of some constraints, allowing an easier relaxed problem to be solved. Relaxation techniques complement or supplement branch and bound algorithms of combinatorial optimization; linear programming and Lagrangian relaxations are used to obtain bounds in branch-and-bound algorithms for integer programming.
The modeling strategy of relaxation should not be confused with iterative methods of relaxation, such as successive over-relaxation (SOR); iterative methods of relaxation are used in solving problems in differential equations, linear least-squares, and linear programming. However, iterative methods of relaxation have been used to solve Lagrangian relaxations.
Definition
A relaxation of the minimization problem
is another minimization problem of the form
with these two properties
for all .
The first property states that the original problem's feasible domain is a subset of the relaxed problem's feasible domain. The second property states that the original problem's objective-function is greater than or equal to the relaxed problem's objective-function.
Properties
If is an optimal solution of the original problem, then and . Therefore, provides an upper bound on .
If in addition to the previous assumptions, , , the following holds: If an optimal solution for the relaxed problem is feasible for the original problem, then it is optimal for the original problem.
Some relaxation techniques
Linear programming relaxation
Lagrangian re
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https://en.wikipedia.org/wiki/Predicate%20abstraction
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In logic, predicate abstraction is the result of creating a predicate from a formula. If Q is any formula then the predicate abstract formed from that sentence is (λx.Q), where λ is an abstraction operator and in which every occurrence of x that is free in Q is bound by λ in (λx.Q). The resultant predicate (λx.Q(x)) is a monadic predicate capable of taking a term t as argument as in (λx.Q(x))(t), which says that the object denoted by 't' has the property of being such that Q.
The states ( λx.Q(x) )(t) ≡ Q(t/x) where Q(t/x) is the result of replacing all free occurrences of x in Q by t. This law is shown to fail in general in at least two cases: (i) when t is irreferential and (ii) when Q contains modal operators.
In modal logic the "de re / de dicto distinction" is stated as
1. (DE DICTO):
2. (DE RE): .
In (1) the modal operator applies to the formula A(t) and the term t is within the scope of the modal operator. In (2) t is not within the scope of the modal operator.
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https://en.wikipedia.org/wiki/Accra%20Declaration
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The Accra Declaration confirmed the support of the two main healthcare interoperability standards by the open source community. With the support of major open source advocates, this allowed free and unfettered access to the core healthcare interoperability standards which resulted in a substantial increase in their usage. The International Healthcare Modelling Standards Development Organisation (IHMSDO) had earlier placed the intellectual property (IP) of the HL7 and DICOM standards and the IHE profiles into the public domain under the creative commons licence.
The declaration was signed at the May 2015 IHMSDO Standards and Implementation Meeting in Ghana.
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https://en.wikipedia.org/wiki/Brian%20Wowk
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Brian G. Wowk is a Canadian medical physicist and cryobiologist known for the discovery and development of synthetic molecules that mimic the activity of natural antifreeze proteins in cryopreservation applications, sometimes called "ice blockers". As a senior scientist at 21st Century Medicine, Inc., he was a co-developer with Greg Fahy of key technologies enabling cryopreservation of large and complex tissues, including the first successful vitrification and transplantation of a mammalian organ (kidney). Wowk is also known for early theoretical work on future applications of molecular nanotechnology, especially cryonics, nanomedicine, and optics. In the early 1990s he wrote that nanotechnology would revolutionize optics, making possible virtual reality display systems optically indistinguishable from real scenery as in the fictitious Holodeck of Star Trek. These systems were described by Wowk in the chapter "Phased Array Optics" in the 1996 anthology Nanotechnology: Molecular Speculations on Global Abundance , and highlighted in the September 1998 Technology Watch section of Popular Mechanics magazine.
Early life and education
He obtained his undergraduate and graduate degrees from the University of Manitoba in Winnipeg, Canada. Dr. Wowk obtained his PhD in physics in 1997. His graduate studies included work in online portal imaging for radiotherapy at the Manitoba Cancer Treatment and Research Foundation (now Cancer Care Manitoba), and work on artifact reduction for functional magnetic resonance imaging at the National Research Council of Canada. His work in the latter field is cited by several text books, including
Functional MRI which includes an image he obtained of magnetic field changes inside the human body caused by respiration.
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https://en.wikipedia.org/wiki/Pelagicoccus
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Pelagicoccus is a Gram-negative genus of bacteria from the family of Puniceicoccaceae.
Phylogeny
The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI)
See also
List of bacterial orders
List of bacteria genera
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https://en.wikipedia.org/wiki/Alexander%20Ostrowski
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Alexander Markowich Ostrowski (; ; 25 September 1893, in Kiev, Russian Empire – 20 November 1986, in Montagnola, Lugano, Switzerland) was a mathematician.
His father Mark having been a merchant, Alexander Ostrowski attended the Kiev College of Commerce, not a high school, and thus had an insufficient qualification to be admitted to university. However, his talent did not remain undetected: Ostrowski's mentor, Dmitry Grave, wrote to Landau and Hensel for help.
Subsequently, Ostrowski began to study mathematics at Marburg University under Hensel's supervision in 1912. During World War I he was interned, but thanks to the intervention of Hensel, the restrictions on his movements were eased somewhat, and he was allowed to use the university library.
After the war ended Ostrowski moved to Göttingen where he wrote his doctoral dissertation and was influenced by Hilbert, Klein and Landau. In 1920, after having obtained his doctorate, Ostrowski moved to Hamburg where he worked as Hecke's assistant and finished his habilitation in 1922. In 1923 he returned to Göttingen, and in 1928 became Professor of Mathematics at Basel, until retirement in 1958. In 1950 Ostrowski obtained Swiss citizenship. After retirement he still published scientific papers until his late eighties.
Selected publications
Vorlesungen über Differential- und Integralrechnung, 3 vols., Birkhäuser; vol. 1, 1945; vol. 1, 2nd edition, 1960; vol. 2, 1951; vol. 3, 1954;
Solution of equations and systems of equations. Academic Press, New York 1960; 2nd edition 1965; 2016 pbk reprint of 2nd edition
Aufgabensammlung zur Infinitesimalrechnung. several vols., Birkhäuser, Basel (1st edition 1964; 2nd edition 1972) pbk reprint vol. 1; vol. 2 A; vol. 2 B; vol. 3
Collected mathematical papers. 6 vols., Birkhäuser, Basel 1983–1984. vol. 1; vol. 2; vol. 3; vol. 4; vol. 5; vol. 6
See also
Ostrowski's theorem
Ostrowski–Hadamard gap theorem
Ostrowski numeration
Ostrowski Prize
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https://en.wikipedia.org/wiki/Peter%20Debye%20Award
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The Peter Debye Award in Physical Chemistry is awarded annually by the American Chemical Society "to encourage and reward outstanding research in physical chemistry". The award is named after Peter Debye and
granted without regard to age or nationality.
Recipients
2020 Laura Gagliardi
2019 Daniel M. Neumark
2018
2017
2016 Mark A. Ratner
2015 Xiaoliang Sunney Xie
2014 Henry F. Schaefer III
2013 William E. Moerner
2012 David Chandler
2011 Louis E. Brus
2010 George Schatz
2009 Richard J. Saykally
2008 Michael L. Klein
2007 John T. Yates, Jr.
2006 Donald Truhlar
2005 Stephen Leone
2004 William Carl Lineberger
2003 William H. Miller
2002 Giacinto Scoles
2001 John Ross
2000 Peter G. Wolynes
1999 Jesse L. Beauchamp
1998 Graham R. Fleming
1997 Robin M. Hochstrasser
1996 Ahmed Zewail
1995 John C. Tully
1994 William A. Klemperer
1993 F. Sherwood Rowland
1992 Frank H. Stillinger
1991 Richard N. Zare
1990 Harden M. McConnell
1989 Gabor A. Somorjai
1988 Rudolph A. Marcus
1987 Harry G. Drickamer
1986 Yuan T. Lee
1985 Stuart A. Rice
1984 B. Seymour Rabinovitch
1983 George C. Pimentel
1982 Peter M. Rentzepis
1981 Richard B. Bernstein
1976 Robert W. Zwanzig
1975 Herbert S. Gutowsky
1974 Walter H. Stockmayer
1973 William N. Lipscomb, Jr.
1972 Clyde A. Hutchison, Jr.
1971 Norman Davidson
1970
1969 Paul J. Flory
1968 George B. Kistiakowsky
1967 Joseph E. Mayer
1966 Joseph O. Hirschfelder
1965 Lars Onsager
1964 Henry Eyring
1963 Robert S. Mulliken
1962 E. Bright Wilson, Jr.
See also
List of chemistry awards
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https://en.wikipedia.org/wiki/Haptic%20technology
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Haptic technology (also kinaesthetic communication or 3D touch) is technology that can create an experience of touch by applying forces, vibrations, or motions to the user. These technologies can be used to create virtual objects in a computer simulation, to control virtual objects, and to enhance remote control of machines and devices (telerobotics). Haptic devices may incorporate tactile sensors that measure forces exerted by the user on the interface. The word haptic, from the (haptikos), means "tactile, pertaining to the sense of touch". Simple haptic devices are common in the form of game controllers, joysticks, and steering wheels.
Haptic technology facilitates investigation of how the human sense of touch works by allowing the creation of controlled haptic virtual objects. Most researchers distinguish three sensory systems related to sense of touch in humans: cutaneous, kinaesthetic and haptic. All perceptions mediated by cutaneous and kinaesthetic sensibility are referred to as tactual perception. The sense of touch may be classified as passive and active, and the term "haptic" is often associated with active touch to communicate or recognize objects.
History
One of the earliest applications of haptic technology was in large aircraft that use servomechanism systems to operate control surfaces. In lighter aircraft without servo systems, as the aircraft approached a stall, the aerodynamic buffeting (vibrations) was felt in the pilot's controls. This was a useful warning of a dangerous flight condition. Servo systems tend to be "one-way," meaning external forces applied aerodynamically to the control surfaces are not perceived at the controls, resulting in the lack of this important sensory cue. To address this, the missing normal forces are simulated with springs and weights. The angle of attack is measured, and as the critical stall point approaches a stick shaker is engaged which simulates the response of a simpler control system. Alternatively, the serv
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https://en.wikipedia.org/wiki/Ontology%20language
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In computer science and artificial intelligence, ontology languages are formal languages used to construct ontologies. They allow the encoding of knowledge about specific domains and often include reasoning rules that support the processing of that knowledge. Ontology languages are usually declarative languages, are almost always generalizations of frame languages, and are commonly based on either first-order logic or on description logic.
Classification of ontology languages
Classification by syntax
Traditional syntax ontology languages
Common Logic - and its dialects
CycL
DOGMA (Developing Ontology-Grounded Methods and Applications)
F-Logic (Frame Logic)
FO-dot (First-order logic extended with types, arithmetic, aggregates and inductive definitions)
KIF (Knowledge Interchange Format)
Ontolingua based on KIF
KL-ONE
KM programming language
LOOM (ontology)
OCML (Operational Conceptual Modelling Language)
OKBC (Open Knowledge Base Connectivity)
PLIB (Parts LIBrary)
RACER
Markup ontology languages
These languages use a markup scheme to encode knowledge, most commonly with XML.
DAML+OIL
Ontology Inference Layer (OIL)
Web Ontology Language (OWL)
Resource Description Framework (RDF)
RDF Schema (RDFS)
SHOE
Controlled natural languages
Attempto Controlled English
Open vocabulary natural languages
Executable English
Classification by structure (logic type)
Frame-based
Three languages are completely or partially frame-based languages.
F-Logic
OKBC
KM
Description logic-based
Description logic provides an extension of frame languages, without going so far as to take the leap to first-order logic and support for arbitrary predicates.
KL-ONE
RACER
OWL.
Gellish is an example of a combined ontology language and ontology that is description logic based. It distinguishes between the semantic differences among others of:
relation types for relations between concepts (classes)
relation types for relations between individuals
relation types
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https://en.wikipedia.org/wiki/Hamartoma
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A hamartoma is a mostly benign, local malformation of cells that resembles a neoplasm of local tissue but is usually due to an overgrowth of multiple aberrant cells, with a basis in a systemic genetic condition, rather than a growth descended from a single mutated cell (monoclonality), as would typically define a benign neoplasm/tumor. Despite this, many hamartomas are found to have clonal chromosomal aberrations that are acquired through somatic mutations, and on this basis the term hamartoma is sometimes considered synonymous with neoplasm. Hamartomas are by definition benign, slow-growing or self-limiting, though the underlying condition may still predispose the individual towards malignancies.
Hamartomas are usually caused by a genetic syndrome that affects the development cycle of all or at least multiple cells. Many of these conditions are classified as overgrowth syndromes or cancer syndromes. Hamartomas occur in many different parts of the body and are most often asymptomatic incidentalomas (undetected until they are found incidentally on an imaging study obtained for another reason). Additionally, the definition of hamartoma versus benign neoplasm is often unclear, since both lesions can be clonal. Lesions such as adenomas, developmental cysts, hemangiomas, lymphangiomas and rhabdomyomas within the kidneys, lungs or pancreas are interpreted by some experts as hamartomas while others consider them true neoplasms. Moreover, even though hamartomas show a benign histology, there is a risk of some rare but life-threatening complications such as those found in neurofibromatosis type I and tuberous sclerosis.
It is different from choristoma, a closely related form of heterotopia. The two can be differentiated as follows: a hamartoma is an excess of normal tissue in a normal situation (e.g., a birthmark on the skin), while a choristoma is an excess of tissue in an abnormal situation (e.g., pancreatic tissue in the duodenum). The term hamartoma is from the Greek ἁ
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https://en.wikipedia.org/wiki/Hyperbolic%20space
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In mathematics, hyperbolic space of dimension n is the unique simply connected, n-dimensional Riemannian manifold of constant sectional curvature equal to -1. It is homogeneous, and satisfies the stronger property of being a symmetric space. There are many ways to construct it as an open subset of with an explicitly written Riemannian metric; such constructions are referred to as models. Hyperbolic 2-space, H2, which was the first instance studied, is also called the hyperbolic plane.
It is also sometimes referred to as Lobachevsky space or Bolyai–Lobachevsky space after the names of the author who first published on the topic of hyperbolic geometry. Sometimes the qualificative "real" is added to differentiate it from complex hyperbolic spaces, quaternionic hyperbolic spaces and the octononic hyperbolic plane which are the other symmetric spaces of negative curvature.
Hyperbolic space serves as the prototype of a Gromov hyperbolic space which is a far-reaching notion including differential-geometric as well as more combinatorial spaces via a synthetic approach to negative curvature. Another generalisation is the notion of a CAT(-1) space.
Formal definition and models
Definition
The -dimensional hyperbolic space or Hyperbolic -space, usually denoted , is the unique simply connected, -dimensional complete Riemannian manifold with a constant negative sectional curvature equal to -1. The unicity means that any two Riemannian manifolds which satisfy these properties are isometric to each other. It is a consequence of the Killing–Hopf theorem.
Models of hyperbolic space
To prove the existence of such a space as described above one can explicitly construct it, for example as an open subset of with a Riemannian metric given by a simple formula. There are many such constructions or models of hyperbolic space, each suited to different aspects of its study. They are isometric to each other according to the previous paragraph, and in each case an explicit isometry can
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https://en.wikipedia.org/wiki/HSPB7
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Heat Shock Protein Family B (small) member 7 (HSPB7) in humans is a protein encoded by a gene of the same name with four exons that is located on chromosome 1p36.13.,. HSPB7 contains 170 amino acids and has a molecular weight of 18,611Da. HSPB7 is a member of human small heat shock protein (HSPB) family, which contains eleven family members of chaperone proteins. HSPB7 and its gene pair SRARP are located 5 kb apart on the opposite strands of chromosome 1p36.13.
Expression and molecular function
HSPB7 is widely expressed throughout the body and its highest expression is observed in the cardiac tissue ,. HSPB protein family, including HSPB7, act protectively on aggregation of several proteins containing an extended polyglutamine (polyQ) stretch that are linked to a variety of neurodegenerative diseases. Among these proteins, HSPB7 is the most potent polyQ aggregation suppressor within the HSPB family of chaperones. In addition, HSPB7 protein contains a HSP20 domain and strongly interacts with the chaperone protein 14-3-3. An interaction with the 14-3-3 protein is a common molecular feature between HSPB7 and SRARP proteins ,
Role in cardiomyopathy and Cancer
HSPB7 has cardiac protective functions and mutations in this gene leads to cardiomyopathies. It has been suggested that HSPB7 cardioprotective function is mediated by facilitating sarcomeric proteostasis. Furthermore, HSPB7 is widely inactivated in malignancies by copy-number loss and epigenetic silencing and the overexpression of this protein results in a tumor suppressor function in multiple cancer cell lines,. The overexpression of HSPB7 and its gene pair SRARP lead to a reduction in the relative phosphorylation and/or expression of Akt and ERK in cancer cells. In addition, it has been suggested that HSBP7 is regulated by p53 tumor suppressor in renal cell carcinoma.
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https://en.wikipedia.org/wiki/Australian%20Dung%20Beetle%20Project
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The Australian Dung Beetle Project (1965–1985), conceived and led by Dr George Bornemissza of the Commonwealth Scientific and Industrial Research Organisation (CSIRO), was an international scientific research and biological control project with the primary goal to control the polluting effects of cattle dung.
Background and inception
Upon his arrival to Australia from Hungary in 1951, Dr Bornemissza, an entomologist and ecologist, noted that Australian farmland was covered in a large number of cattle dung pads. This was in contrast to the fields of Europe where the dung was removed and recycled back into the soil by various species of dung beetle (coprids). Native Australian species of beetle had co-evolved alongside marsupials such as the kangaroo and wombat, which produce small, hard, dry and fibrous pellets of dung. Cattle were relatively recently introduced to Australia by European settlers in the 1880s and produce large, soft, moist dung pads. Native beetles, with a few exceptions, are not adapted to utilise this type of dung as a food source or breeding ground and so without such fauna, the dung pads remain on the pasture and take months or even years to decompose. Cattle will not feed from the area of rank pasture surrounding the dung pad, and with the large quantity of dung produced (up to 12 pads per animal per day), this reduces the area of land available for cattle grazing by as much as per year. Cattle dung is also a primary breeding ground for several pestilent species of fly and parasitic worm. Bornemissza suggested in 1960 that the introduction to Australia of foreign dung beetle species, which had co-evolved alongside bovines and large herbivores, would be beneficial in removing the dung, thus improving cattle grazing and nutrient recycling and reducing the number of flies and worms.
Aims of the project
The overall aim of the Australian Dung Beetle Project was to establish a "minifauna", that is, a subsection of the natural dung beetle fauna, of
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https://en.wikipedia.org/wiki/Quantum%20radar
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Quantum radar is a speculative remote-sensing technology based on quantum-mechanical effects, such as the uncertainty principle or quantum entanglement. Broadly speaking, a quantum radar can be seen as a device working in the microwave range, which exploits quantum features, from the point of view of the radiation source and/or the output detection, and is able to outperform a classical counterpart. One approach is based on the use of input quantum correlations (in particular, quantum entanglement) combined with a suitable interferometric quantum detection at the receiver (strongly related to the protocol of quantum illumination).
Paving the way for a technologically-viable prototype of a quantum radar involves the resolution of a number of experimental challenges as discussed in some review articles, the latter of which pointed out "inaccurate reporting" in the media. Current experimental designs seem to be limited to very short ranges, of the order of one meter, suggesting that potential applications might instead be for near-distance surveillance or biomedical scanning.
Concept behind a microwave-range model
A microwave-range model of a quantum radar was proposed in 2015 by an international team and is based on the protocol of Gaussian quantum illumination. The basic concept is to create a stream of entangled visible-frequency photons and split it in half. One half, the "signal beam", goes through a conversion to microwave frequencies in a way that preserves the original quantum state. The microwave signal is then sent and received as in a normal radar system. When the reflected signal is received it is converted back into visible photons and compared with the other half of the original entangled beam, the "idler beam".
Although most of the original entanglement will be lost due to quantum decoherence as the microwaves travel to the target objects and back, enough quantum correlations will still remain between the reflected-signal and the idler beams. Using
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https://en.wikipedia.org/wiki/Dwarfism%20in%20chickens
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Dwarfism in chickens is an inherited condition found in chickens consisting of a significant delayed growth, resulting in adult individuals with a distinctive small size in comparison with normal specimens of the same breed or population.
The affected birds show no signs of dwarfism in the first weeks of age. Differences in size due to dwarfism appear slow and progressively along the growing stage. Poultry breeders begin to distinguish gradually dwarfs from normal birds by their shortest shanks and smallest body size. Depending on the breed, most types of dwarfism in chickens begin to be recognized when the birds reach 8–10 weeks of age, but classification is more precise when the chickens are five months old or more. At this point differences between normal and dwarf sibs is evident in all males and in 98% of the females. Dwarfs chickens reach sexual maturity and reproduce normally.
Dwarfism in chickens has been found to be controlled by several simple genetic factors. Some types are autosomic while others are sex-linked, but when poultry breeders make reference to 'dwarf chickens' they usually refer implicitly to sex-linked recessive dwarfism due to the recessive gene dw, located on the Z chromosome.
As sex-linked dwarf broiler breeder hens can bring about normal sized broiler chickens, sex-linked recessive dwarfism found application in poultry industry since the last decades of the 20th century.
These hens require less food and less housing space. Their feed intake do not need to be restricted. They also have more tolerance to heat (see: Advantages...). So the use of sex-linked dwarf broiler female parent stocks helps to save costs and to improve animal welfare and economic efficiency in European broiler industry (see: Use of...). But in spite of the proven advantages of raising dwarf breeder hens, their use is not generalized in broiler industry.
Autosomal types of dwarfism
Two different types of autosomal dwarfisms have been found in chickens. These ty
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https://en.wikipedia.org/wiki/Steve%20Schneider%20%28computer%20scientist%29
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Steve Schneider FBCS, CITP is an English computer scientist and Professor of Security. He is Director of the Surrey Centre for Cyber Security and Associate Dean (Research and Enterprise) at the University of Surrey.
Biography
Steve Schneider studied at Oxford University, joining the Oxford University Computing Laboratory (now the Oxford University Department of Computer Science) to study for a Doctorate on CSP, which was awarded in 1989, supervised by Mike Reed. He joined Royal Holloway, University of London as a lecturer in 1994, becoming a senior lecturer in 1999 and a professor in 2002. He moved to the University of Surrey in 2004, and was head of the Department of Computer Science from 2004 until 2010.
Schneider is an expert in formal methods, including Communicating Sequential Processes (CSP) and the B-Method, and computer security.
Selected books
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