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https://en.wikipedia.org/wiki/Gahnite
Gahnite, ZnAl2O4, is a rare mineral belonging to the spinel group. It forms octahedral crystals which may be green, blue, yellow, brown or grey. It often forms as an alteration product of sphalerite in altered massive sulphide deposits such as at Broken Hill, Australia. Other occurrences include Falun, Sweden where it is found in pegmatites and skarns; and, in the United States, Charlemont, Massachusetts; Spruce Pine, North Carolina; White Picacho district, Arizona; Topsham, Maine; and Franklin, New Jersey. It was first described in 1807 for an occurrence in the Falu mine, Falun, Dalarna, Sweden, and named after the Swedish chemist, Johan Gottlieb Gahn (1745–1818), the discoverer of the element manganese. It is sometimes called zinc spinel. See also List of minerals named after people References Zinc minerals Aluminium minerals Spinel group Cubic minerals Minerals in space group 227 Minerals described in 1807
https://en.wikipedia.org/wiki/North%20New%20Guinea%20languages
The North New Guinea languages of Papua New Guinea and Indonesia form a possible linkage of Western Oceanic languages. They have been in heavy contact with Papuan languages. Classification According to Lynch, Ross, & Crowley (2002), the structure of the family is as follows: ? Sarmi–Jayapura family Schouten linkage Huon Gulf family Ngero–Vitiaz linkage The center of dispersal was evidently near the Vitiaz Strait between New Britain and the New Guinea mainland. The inclusion of Sarmi and Jayapura Bay is uncertain, and it may constitute a separate branch of Western Oceanic. References Ross, Malcolm (1988). Proto Oceanic and the Austronesian languages of western Melanesia. Canberra: Pacific Linguistics. Western Oceanic languages Languages of Papua New Guinea Languages of western New Guinea Papua (province) culture
https://en.wikipedia.org/wiki/Pohlig%E2%80%93Hellman%20algorithm
In group theory, the Pohlig–Hellman algorithm, sometimes credited as the Silver–Pohlig–Hellman algorithm, is a special-purpose algorithm for computing discrete logarithms in a finite abelian group whose order is a smooth integer. The algorithm was introduced by Roland Silver, but first published by Stephen Pohlig and Martin Hellman (independent of Silver). Groups of prime-power order As an important special case, which is used as a subroutine in the general algorithm (see below), the Pohlig–Hellman algorithm applies to groups whose order is a prime power. The basic idea of this algorithm is to iteratively compute the -adic digits of the logarithm by repeatedly "shifting out" all but one unknown digit in the exponent, and computing that digit by elementary methods. (Note that for readability, the algorithm is stated for cyclic groups — in general, must be replaced by the subgroup generated by , which is always cyclic.) Input. A cyclic group of order with generator and an element . Output. The unique integer such that . Initialize Compute . By Lagrange's theorem, this element has order . For all , do: Compute . By construction, the order of this element must divide , hence . Using the baby-step giant-step algorithm, compute such that . It takes time . Set . Return . Assuming is much smaller than , the algorithm computes discrete logarithms in time complexity , far better than the baby-step giant-step algorithm's . The general algorithm In this section, we
https://en.wikipedia.org/wiki/Spectral%20resolution
The spectral resolution of a spectrograph, or, more generally, of a frequency spectrum, is a measure of its ability to resolve features in the electromagnetic spectrum. It is usually denoted by , and is closely related to the resolving power of the spectrograph, defined as where is the smallest difference in wavelengths that can be distinguished at a wavelength of . For example, the Space Telescope Imaging Spectrograph (STIS) can distinguish features 0.17 nm apart at a wavelength of 1000 nm, giving it a resolution of 0.17 nm and a resolving power of about 5,900. An example of a high resolution spectrograph is the Cryogenic High-Resolution IR Echelle Spectrograph (CRIRES+) installed at ESO's Very Large Telescope, which has a spectral resolving power of up to 100,000. Doppler effect The spectral resolution can also be expressed in terms of physical quantities, such as velocity; then it describes the difference between velocities that can be distinguished through the Doppler effect. Then, the resolution is and the resolving power is where is the speed of light. The STIS example above then has a spectral resolution of 51 km/s. IUPAC definition IUPAC defines resolution in optical spectroscopy as the minimum wavenumber, wavelength or frequency difference between two lines in a spectrum that can be distinguished. Resolving power, R, is given by the transition wavenumber, wavelength or frequency, divided by the resolution. See also Angular resolution Resolution (mass spe
https://en.wikipedia.org/wiki/Purex
Purex may refer to: PUREX (plutonium uranium reduction extraction), a reprocessing process for spent nuclear fuel Purex (laundry detergent), a brand of detergent Purex Crystals, a laundry fragrance booster Toilet tissue brand by Kruger Inc.
https://en.wikipedia.org/wiki/Grain%20boundary
In materials science, a grain boundary is the interface between two grains, or crystallites, in a polycrystalline material. Grain boundaries are two-dimensional defects in the crystal structure, and tend to decrease the electrical and thermal conductivity of the material. Most grain boundaries are preferred sites for the onset of corrosion and for the precipitation of new phases from the solid. They are also important to many of the mechanisms of creep. On the other hand, grain boundaries disrupt the motion of dislocations through a material, so reducing crystallite size is a common way to improve mechanical strength, as described by the Hall–Petch relationship. High and low angle boundaries It is convenient to categorize grain boundaries according to the extent of misorientation between the two grains. Low-angle grain boundaries (LAGB) or subgrain boundaries are those with a misorientation less than about 15 degrees. Generally speaking they are composed of an array of dislocations and their properties and structure are a function of the misorientation. In contrast the properties of high-angle grain boundaries, whose misorientation is greater than about 15 degrees (the transition angle varies from 10–15 degrees depending on the material), are normally found to be independent of the misorientation. However, there are 'special boundaries' at particular orientations whose interfacial energies are markedly lower than those of general high-angle grain boundaries. The simplest
https://en.wikipedia.org/wiki/List%20of%20environmental%20dates
This is a list of environmental dates which are designated for creating awareness of environmental issues. Species awareness days highlight biodiversity, with the aim of increasing understanding and appreciation of the subject. Some of these days have been shown to cause a rise in information-seeking behaviour, and may lead to an increase in conservation fundraising by charities and advocacy groups. Hours Earth Hour - 8:30pm (local time), next one will take place on 23 March 2024. Days of environment Weeks Years Agriculture Decades See also Index of environmental articles List of environmental issues Index of conservation articles List of conservation issues List of international environmental agreements List of awareness days International observance List of commemorative days List of commemorative months References External links News & Events - UN Days, Weeks and Years - World Plantation Day, Great Kashmir - Save your water - EDU Green Environmental
https://en.wikipedia.org/wiki/Nucleation
In thermodynamics, nucleation is the first step in the formation of either a new thermodynamic phase or structure via self-assembly or self-organization within a substance or mixture. Nucleation is typically defined to be the process that determines how long an observer has to wait before the new phase or self-organized structure appears. For example, if a volume of water is cooled (at atmospheric pressure) below 0°C, it will tend to freeze into ice, but volumes of water cooled only a few degrees below 0°C often stay completely free of ice for long periods (supercooling). At these conditions, nucleation of ice is either slow or does not occur at all. However, at lower temperatures nucleation is fast, and ice crystals appear after little or no delay. Nucleation is a common mechanism which generates first-order phase transitions, and it is the start of the process of forming a new thermodynamic phase. In contrast, new phases at continuous phase transitions start to form immediately. Nucleation is often very sensitive to impurities in the system. These impurities may be too small to be seen by the naked eye, but still can control the rate of nucleation. Because of this, it is often important to distinguish between heterogeneous nucleation and homogeneous nucleation. Heterogeneous nucleation occurs at nucleation sites on surfaces in the system. Homogeneous nucleation occurs away from a surface. Characteristics Nucleation is usually a stochastic (random) process, so even in t
https://en.wikipedia.org/wiki/Cytochrome%20b6f%20complex
The cytochrome b6f complex (plastoquinol—plastocyanin reductase; ) is an enzyme found in the thylakoid membrane in chloroplasts of plants, cyanobacteria, and green algae, that catalyzes the transfer of electrons from plastoquinol to plastocyanin. The reaction is analogous to the reaction catalyzed by cytochrome bc1 (Complex III) of the mitochondrial electron transport chain. During photosynthesis, the cytochrome b6f complex is one step along the chain that transfers electrons from Photosystem II to Photosystem I, and at the same time pumps protons into the thylakoid space, contributing to the generation of an electrochemical (energy) gradient that is later used to synthesize ATP from ADP. Enzyme structure The cytochrome b6f complex is a dimer, with each monomer composed of eight subunits. These consist of four large subunits: a 32 kDa cytochrome f with a c-type cytochrome, a 25 kDa cytochrome b6 with a low- and high-potential heme group, a 19 kDa Rieske iron-sulfur protein containing a [2Fe-2S] cluster, and a 17 kDa subunit IV; along with four small subunits (3-4 kDa): PetG, PetL, PetM, and PetN. The total molecular weight is 217 kDa. The crystal structures of cytochrome b6f complexes from Chlamydomonas reinhardtii, Mastigocladus laminosus, and Nostoc sp. PCC 7120 have been determined. The core of the complex is structurally similar to the cytochrome bc1 core. Cytochrome b6 and subunit IV are homologous to cytochrome b, and the Rieske iron-sulfur proteins of the two com
https://en.wikipedia.org/wiki/Microtubule-associated%20protein
In cell biology, microtubule-associated proteins (MAPs) are proteins that interact with the microtubules of the cellular cytoskeleton. MAPs are integral to the stability of the cell and its internal structures and the transport of components within the cell. Function MAPs bind to the tubulin subunits that make up microtubules to regulate their stability. A large variety of MAPs have been identified in many different cell types, and they have been found to carry out a wide range of functions. These include both stabilizing and destabilizing microtubules, guiding microtubules towards specific cellular locations, cross-linking microtubules and mediating the interactions of microtubules with other proteins in the cell. Within the cell, MAPs bind directly to the tubulin dimers of microtubules. This binding can occur with either polymerized or depolymerized tubulin, and in most cases leads to the stabilization of microtubule structure, further encouraging polymerization. Usually, it is the C-terminal domain of the MAP that interacts with tubulin, while the N-terminal domain can bind with cellular vesicles, intermediate filaments or other microtubules. MAP-microtubule binding is regulated through MAP phosphorylation. This is accomplished through the function of the microtubule-affinity-regulating-kinase (MARK) protein. Phosphorylation of the MAP by the MARK causes the MAP to detach from any bound microtubules. This detachment is usually associated with a destabilization of the mic
https://en.wikipedia.org/wiki/Crystal%20twinning
Crystal twinning occurs when two or more adjacent crystals of the same mineral are oriented so that they share some of the same crystal lattice points in a symmetrical manner. The result is an intergrowth of two separate crystals that are tightly bonded to each other. The surface along which the lattice points are shared in twinned crystals is called a composition surface or twin plane. Crystallographers classify twinned crystals by a number of twin laws. These twin laws are specific to the crystal structure. The type of twinning can be a diagnostic tool in mineral identification. Deformation twinning, in which twinning develops in a crystal in response to a shear stress, is an important mechanism for permanent shape changes in a crystal. Definition Twinning is a form of symmetrical intergrowth between two or more adjacent crystals of the same mineral. It differs from the ordinary random intergrowth of mineral grains in a mineral deposit, because the relative orientations of the two crystal segments show a fixed relationship that is characteristic of the mineral structure. The relationship is defined by a symmetry operation called a twin operation. The twin operation is not one of the normal symmetry operations of the untwinned crystal structure. For example, the twin operation may be reflection across a plane that is not a symmetry plane of the single crystal. On the microscopic level, the twin boundary is characterized by a set of atomic positions in the crystal latt
https://en.wikipedia.org/wiki/Indirect%20utility%20function
In economics, a consumer's indirect utility function gives the consumer's maximal attainable utility when faced with a vector of goods prices and an amount of income . It reflects both the consumer's preferences and market conditions. This function is called indirect because consumers usually think about their preferences in terms of what they consume rather than prices. A consumer's indirect utility can be computed from his or her utility function defined over vectors of quantities of consumable goods, by first computing the most preferred affordable bundle, represented by the vector by solving the utility maximization problem, and second, computing the utility the consumer derives from that bundle. The resulting indirect utility function is The indirect utility function is: Continuous on Rn+ × R+ where n is the number of goods; Decreasing in prices; Strictly increasing in income; Homogenous with degree zero in prices and income; if prices and income are all multiplied by a given constant the same bundle of consumption represents a maximum, so optimal utility does not change; quasi-convex in (p,w). Moreover, Roy's identity states that if v(p,w) is differentiable at and , then Indirect utility and expenditure The indirect utility function is the inverse of the expenditure function when the prices are kept constant. I.e, for every price vector and utility level : Example Let's say the utility function is the Cobb-Douglas function which has the Marshallian
https://en.wikipedia.org/wiki/Dopamine%20receptor%20D4
{{DISPLAYTITLE:Dopamine receptor D4}} The dopamine receptor D4 is a dopamine D2-like G protein-coupled receptor encoded by the gene on chromosome 11 at 11p15.5. The structure of DRD4 was recently reported in complex with the antipsychotic drug nemonapride. As with other dopamine receptor subtypes, the D4 receptor is activated by the neurotransmitter dopamine. It is linked to many neurological and psychiatric conditions including schizophrenia and bipolar disorder, ADHD, addictive behaviors, Parkinson's disease, and eating disorders such as anorexia nervosa. A weak association has been drawn between DRD4 and borderline personality disorder. It is also a target for drugs which treat schizophrenia and Parkinson's disease. The D4 receptor is considered to be D2-like in which the activated receptor inhibits the enzyme adenylate cyclase, thereby reducing the intracellular concentration of the second messenger cyclic AMP. Genetics The human protein is coded by the DRD4 on chromosome 11 located in 11p15.5. There are slight variations (mutations/polymorphisms) in the human gene: A 48-base pair VNTR in exon 3 C-521T in the promoter 13-base pair deletion of bases 235 to 247 in exon 1 12 base pair repeat in exon 1 Val194Gly A polymorphic tandem duplication of 48 bp Mutations in this gene have been associated with various behavioral phenotypes, including autonomic nervous system dysfunction, attention deficit/hyperactivity disorder, schizophrenia and the personality trait
https://en.wikipedia.org/wiki/Turbomachinery
Turbomachinery, in mechanical engineering, describes machines that transfer energy between a rotor and a fluid, including both turbines and compressors. While a turbine transfers energy from a fluid to a rotor, a compressor transfers energy from a rotor to a fluid. These two types of machines are governed by the same basic relationships including Newton's second Law of Motion and Euler's pump and turbine equation for compressible fluids. Centrifugal pumps are also turbomachines that transfer energy from a rotor to a fluid, usually a liquid, while turbines and compressors usually work with a gas. History The first turbomachines could be identified as water wheels, which appeared between the 3rd and 1st centuries BCE in the Mediterranean region. These were used throughout the medieval period and began the first Industrial Revolution. When steam power started to be used, as the first power source driven by the combustion of a fuel rather than renewable natural power sources, this was as reciprocating engines. Primitive turbines and conceptual designs for them, such as the smoke jack, appeared intermittently but the temperatures and pressures required for a practically efficient turbine exceeded the manufacturing technology of the time. The first patent for gas turbines were filed in 1791 by John Barber. Practical hydroelectric water turbines and steam turbines did not appear until the 1880s. Gas turbines appeared in the 1930s. The first impulse type turbine was created by Ca
https://en.wikipedia.org/wiki/Simplesse
Simplesse is a multi-functional dairy ingredient made from whey protein concentrate used as a fat substitute in low-calorie foods. Originally brought to market in 1988, the manufacturer, CP Kelco (a former NutraSweet subsidiary), sells Simplesse to food processors as a "microparticulated whey protein concentrate" in dry powder form, and recommends that it be labelled as dairy protein on food labels. Older versions of the product also contain egg whites. The protein is partially coagulated by heat, creating a micro dispersion, in a process known as microparticulation. It is due to the small particle size of the protein that the dispersion is perceivable as a fluid with similar creaminess and richness of fat. History Simplesse began in 1979 as "a substance that gelled like egg white but crumbled like Styrofoam." At that time, Shoji Yamamoto, an associate of Norman S. Singer at Canadian beer company John Labatt Ltd. in London, Ontario, brought Singer the whey protein substance. After sensing that it gave the taste texture of cream cheese, another scientist put a sample under a powerful microscope and saw "tiny spheres of protein rolling over each other" about a tenth the size of particles of powdered sugar. It was this particle rolling action that gave a smooth creaminess sensation. Another associate of Singer, scientist Nina Davis, worked for three years with Simplesse (then called microcurd) to adapt it to and incorporate it into many different food products. After Singer's
https://en.wikipedia.org/wiki/Sub-bass
Sub-bass sounds are the deep, low-register pitches below approximately 70 Hz (C2 in scientific pitch notation) and extending downward to include the lowest frequency humans can hear, approximately 20 Hz (E0). In this range, human hearing is less sensitive, so these notes tend to be felt more than heard. The low E-string on a bass guitar is usually tuned to 41.2 Hz, while the lowest note on a standard piano is A at 27.5 Hz. Sound reinforcement systems and PA systems often use one or more subwoofer loudspeakers to amplify sounds in the sub-bass range. Sounds below sub-bass are infrasound. Hearing and usage 20 Hz is considered the normal low-frequency limit of human hearing. When pure sine waves are reproduced under ideal conditions and at very high decibels, a human listener will be able to identify tones as low as 12 Hz (G–1). Audio tracks known as bass tests use sub-bass frequencies which are used to test or to demonstrate the capabilities of audio equipment. High-end subwoofers can accurately reproduce sound to about 18 Hz ±2 dB. Sub-bass energy is popular in dance music, where the low frequencies involve energy from the kick drum (bass drum), the bass guitar and electronic synthesizers and drum machines. Particular genres such as house music, drum and bass and dubstep often feature a bassline that consists mainly of sub-bass frequencies. Much experimental music uses sub-bass, in particular drone music, where the majority of the sound can often be in the sub-bass range.
https://en.wikipedia.org/wiki/Min-conflicts%20algorithm
In computer science, the min-conflicts algorithm is a search algorithm or heuristic method to solve constraint satisfaction problems. Given an initial assignment of values to all the variables of a constraint satisfaction problem, the algorithm randomly selects a variable from the set of variables with conflicts violating one or more its constraints. Then it assigns to this variable the value that minimizes the number of conflicts. If there is more than one value with a minimum number of conflicts, it chooses one randomly. This process of random variable selection and min-conflict value assignment is iterated until a solution is found or a pre-selected maximum number of iterations is reached. Because a constraint satisfaction problem can be interpreted as a local search problem when all the variables have an assigned value (called a complete state), the min conflicts algorithm can be seen as a repair heuristic that chooses the state with the minimum number of conflicts. Algorithm algorithm MIN-CONFLICTS is input: console.csp, A constraint satisfaction problem. max_steps, The number of steps allowed before giving up. current_state, An initial assignment of values for the variables in the csp. output: A solution set of values for the variable or failure. for i ← 1 to max_steps do if current_state is a solution of csp then return current_state set var ← a randomly chosen variable from the set of conflic
https://en.wikipedia.org/wiki/Null%20allele
A null allele is a nonfunctional allele (a variant of a gene) caused by a genetic mutation. Such mutations can cause a complete lack of production of the associated gene product or a product that does not function properly; in either case, the allele may be considered nonfunctional. A null allele cannot be distinguished from deletion of the entire locus solely from phenotypic observation. A mutant allele that produces no RNA transcript is called an RNA null (shown by Northern blotting or by DNA sequencing of a deletion allele), and one that produces no protein is called a protein null (shown by Western blotting). A genetic null or amorphic allele has the same phenotype when homozygous as when heterozygous with a deficiency that disrupts the locus in question. A genetic null allele may be both a protein null and an RNA null, but may also express normal levels of a gene product that is nonfunctional due to mutation. Null alleles can have lethal effects depending on the importance of the mutated gene. For example, mice homozygous for a null allele for insulin die 48 to 72 hours after birth. Null alleles can also have beneficial effects, such as the elevated harvest index of semi-dwarf rice of the green revolution caused by null alleles in GA20ox-2. Evidence Polymerase chain reaction (PCR) A microsatellite null allele is an allele at a microsatellite locus that does not amplify to detectable levels in a polymerase chain reaction test. Microsatellite regions are usually chara
https://en.wikipedia.org/wiki/Solutions%20of%20the%20Einstein%20field%20equations
Solutions of the Einstein field equations are metrics of spacetimes that result from solving the Einstein field equations (EFE) of general relativity. Solving the field equations gives a Lorentz manifold. Solutions are broadly classed as exact or non-exact. The Einstein field equations are where is the Einstein tensor, is the cosmological constant (sometimes taken to be zero for simplicity), is the metric tensor, is a constant, and is the stress–energy tensor. The Einstein field equations relate the Einstein tensor to the stress–energy tensor, which represents the distribution of energy, momentum and stress in the spacetime manifold. The Einstein tensor is built up from the metric tensor and its partial derivatives; thus, given the stress–energy tensor, the Einstein field equations are a system of ten partial differential equations in which the metric tensor can be solved for. Where appropriate, this article will use the abstract index notation. Solving the equations It is important to realize that the Einstein field equations alone are not enough to determine the evolution of a gravitational system in many cases. They depend on the stress–energy tensor, which depends on the dynamics of matter and energy (such as trajectories of moving particles), which in turn depends on the gravitational field. If one is only interested in the weak field limit of the theory, the dynamics of matter can be computed using special relativity methods and/or Newtonian laws of gravity and
https://en.wikipedia.org/wiki/Electric-field%20integral%20equation
The electric-field integral equation is a relationship that allows the calculation of an electric field () generated by an electric current distribution (). Derivation When all quantities in the frequency domain are considered, a time-dependency that is suppressed throughout is assumed. Beginning with the Maxwell equations relating the electric and magnetic field, and assuming a linear, homogeneous media with permeability and permittivity : Following the third equation involving the divergence of by vector calculus we can write any divergenceless vector as the curl of another vector, hence where A is called the magnetic vector potential. Substituting this into the above we get and any curl-free vector can be written as the gradient of a scalar, hence where is the electric scalar potential. These relationships now allow us to write where , which can be rewritten by vector identity as As we have only specified the curl of , we are free to define the divergence, and choose the following: which is called the Lorenz gauge condition. The previous expression for now reduces to which is the vector Helmholtz equation. The solution of this equation for is where is the three-dimensional homogeneous Green's function given by We can now write what is called the electric field integral equation (EFIE), relating the electric field to the vector potential A We can further represent the EFIE in the dyadic form as where here is the dyadic homogeneous Green's Function gi
https://en.wikipedia.org/wiki/Magnesium%20silicide
Magnesium silicide, Mg2Si, is an inorganic compound consisting of magnesium and silicon. As-grown Mg2Si usually forms black crystals; they are semiconductors with n-type conductivity and have potential applications in thermoelectric generators. Crystal structure Mg2Si crystallizes in the antifluorite structure. In the face-centered cubic lattice Si centers occupy the corners and face-centered positions of the unit cell and Mg centers occupy eight tetrahedral sites in the interior of the unit cell. The coordination numbers of Si and Mg are eight and four, respectively. Synthesis It can be produced by heating silicon dioxide, SiO2, found in sand, with excess magnesium. The process first forms silicon metal and magnesium oxide, and, if an excess of SiO2 is used, then elemental silicon is formed: 2 Mg + SiO2 → 2 MgO + Si If an excess of Mg is present, Mg2Si is formed from the reaction of the remaining magnesium with the silicon: 2 Mg + Si → Mg2Si These reactions proceed exothermically, even explosively. Reactions Magnesium silicide can be viewed as consisting of Si4− ions. As such it is reactive toward acids. Thus, when magnesium silicide is treated with hydrochloric acid, silane (SiH4) and magnesium chloride are produced: Mg2Si + 4 HCl → SiH4 + 2 MgCl2 Sulfuric acid can be used as well. These protonolysis reactions are typical of a Group 2 alkaline earth metal and Group 1 alkali metal silicides. The early development of silicon hydrides relied on t
https://en.wikipedia.org/wiki/Leukemoid%20reaction
The term leukemoid reaction describes an increased white blood cell count (> 50,000 cells/μL), which is a physiological response to stress or infection (as opposed to a primary blood malignancy, such as leukemia). It often describes the presence of immature cells such as myeloblasts or red blood cells with nuclei in the peripheral blood. It may be lymphoid or myeloid. Causes As noted above, a leukemoid reaction is typically a response to an underlying medical issue. Causes of leukemoid reactions include: Severe hemorrhage (retroperitoneal hemorrhage) Drugs Use of sulfa drugs Use of dapsone Use of glucocorticoids Use of G-CSF or related growth factors All-trans retinoic acid (ATRA) Ethylene glycol intoxication Infections Clostridium difficile Tuberculosis Pertussis Infectious mononucleosis (lymphocyte predominant) Visceral larva migrans (eosinophil predominant) Asplenia Diabetic ketoacidosis Organ necrosis Hepatic necrosis Ischemic colitis As a feature of trisomy 21 in infancy (incidence of ~10%) As a paraneoplastic phenomenon (rare) Diagnosis Conventionally, a leukocytosis exceeding 50,000 WBC/mm3 with a significant increase in early neutrophil precursors is referred to as a leukemoid reaction. The peripheral blood smear may show myelocytes, metamyelocytes, promyelocytes, and rarely myeloblasts; however, there is a mixture of early mature neutrophil precursors, in contrast to the immature forms typically seen in acute leukemia. Serum leukocyte alkal
https://en.wikipedia.org/wiki/Solid-state%20nuclear%20magnetic%20resonance
Solid-state NMR (ssNMR) spectroscopy is a technique for characterizing atomic level structure in solid materials e.g. powders, single crystals and amorphous samples and tissues using nuclear magnetic resonance (NMR) spectroscopy. The anisotropic part of many spin interactions are present in solid-state NMR, unlike in solution-state NMR where rapid tumbling motion averages out many of the spin interactions. As a result, solid-state NMR spectra are characterised by larger linewidths than in solution state NMR, which can be utilized to give quantitative information on the molecular structure, conformation and dynamics of the material. Solid-state NMR is often combined with magic angle spinning to remove anisotropic interactions and improve the resolution as well as the sensitivity of the technique. Nuclear spin interactions The resonance frequency of a nuclear spin depends on the strength of the magnetic field at the nucleus, which can be modified by isotropic (e.g. chemical shift, isotropic J-coupling) and anisotropic interactions (e.g. chemical shift anisotropy, dipolar interactions). In a classical liquid-state NMR experiment, molecular tumbling coming from Brownian motion averages anisotropic interactions to zero and they are therefore not reflected in the NMR spectrum. However, in media with no or little mobility (e.g. crystalline powders, glasses, large membrane vesicles, molecular aggregates), anisotropic local fields or interactions have substantial influence on the beh
https://en.wikipedia.org/wiki/Councilman%20body
In pathology, a Councilman body, also known as a Councilman hyaline body or apoptotic body, is an eosinophilic globule of apoptotic hepatocyte cell fragments. Ultimately, the fragments are taken up by macrophages or adjacent parenchymal cells. They are found in the liver of individuals suffering from acute viral hepatitis, yellow fever, and other viral syndromes. Associated conditions Councilman bodies were first identified in yellow fever, which characteristically shows a midzonal hepatic necrosis on biopsy. Similar inclusions are observed in other viral hemorrhagic fevers and all of the viral hepatitides. Liver biopsy of acute viral hepatitis shows panlobular lymphocytic infiltrates with ballooning hepatocytes. Eponym Councilman bodies are named after American pathologist William Thomas Councilman (1854–1933), who discovered them. See also Ballooning degeneration Feathery degeneration Mallory body References Hepatology
https://en.wikipedia.org/wiki/Boron%20trioxide
Boron trioxide or diboron trioxide is the oxide of boron with the formula . It is a colorless transparent solid, almost always glassy (amorphous), which can be crystallized only with great difficulty. It is also called boric oxide or boria. It has many important industrial applications, chiefly in ceramics as a flux for glazes and enamels and in the production of glasses. Structure Boron trioxide has three known forms, one amorphous and two crystalline. Amorphous form The amorphous form (g-) is by far the most common. It is thought to be composed of boroxol rings which are six-membered rings composed of alternating 3-coordinate boron and 2-coordinate oxygen. Because of the difficulty of building disordered models at the correct density with many boroxol rings, this view was initially controversial, but such models have recently been constructed and exhibit properties in excellent agreement with experiment. It is now recognized, from experimental and theoretical studies, that the fraction of boron atoms belonging to boroxol rings in glassy is somewhere between 0.73 and 0.83, with 0.75 = 3/4 corresponding to a 1:1 ratio between ring and non-ring units. The number of boroxol rings decays in the liquid state with increasing temperature. Crystalline α form The crystalline form (α-) is exclusively composed of BO3 triangles. It crystal structure was initially believed to be the enantiomorphic space groups P31(#144) and P32(#145), like γ-glycine; but was later revised to the e
https://en.wikipedia.org/wiki/Photovoltaic%20effect
The photovoltaic effect is the generation of voltage and electric current in a material upon exposure to light. It is a physical and chemical phenomenon. The photovoltaic effect is closely related to the photoelectric effect. For both phenomena, light is absorbed, causing excitation of an electron or other charge carrier to a higher-energy state. The main distinction is that the term photoelectric effect is now usually used when the electron is ejected out of the material (usually into a vacuum) and photovoltaic effect used when the excited charge carrier is still contained within the material. In either case, an electric potential (or voltage) is produced by the separation of charges, and the light has to have a sufficient energy to overcome the potential barrier for excitation. The physical essence of the difference is usually that photoelectric emission separates the charges by ballistic conduction and photovoltaic emission separates them by diffusion, but some "hot carrier" photovoltaic devices concepts blur this distinction. History The first demonstration of the photovoltaic effect, by Edmond Becquerel in 1839, used an electrochemical cell. He explained his discovery in Comptes rendus de l'Académie des sciences, "the production of an electric current when two plates of platinum or gold immersed in an acid, neutral, or alkaline solution are exposed in an uneven way to solar radiation." The first solar cell, consisting of a layer of selenium covered with a thin film o
https://en.wikipedia.org/wiki/The%20Book%20of%20the%20New%20Sun
The Book of the New Sun (1980–1983) is a four-volume science fantasy novel written by the American author Gene Wolfe. It inaugurated the "Solar Cycle" that Wolfe continued by setting other works in the same universe (The Urth of the New Sun, The Book of the Long Sun series, and The Book of the Short Sun series). Gene Wolfe had originally intended the story to be a 40,000-word novella called "The Feast of Saint Catherine", meant to be published in one of the Orbit anthologies, but during the writing, it continued to grow. Despite being published with a year between each book, all four books were written and completed during his free time without anyone's knowledge when he was still an editor of Plant Engineering, allowing him to write at his own pace and take his time. The tetralogy chronicles the journey of Severian, a journeyman torturer who is disgraced and forced to wander. It is a first-person narrative, ostensibly translated by Wolfe into contemporary English, set in a distant future when the Sun has dimmed and Earth is cooler (a "Dying Earth" story). Severian lives in a nation called the Commonwealth, ruled by the Autarch, in the Southern Hemisphere. It is at war with Ascia, its totalitarian northern neighbor. In a 1998 poll of its subscribers, Locus magazine ranked the tetralogy number three among 36 all-time best fantasy novels before 1990. Plot summary The Shadow of the Torturer Severian, an apprentice in the torturers' guild, barely survives a swim in the Riv
https://en.wikipedia.org/wiki/Plant%20Proteome%20Database
The Plant Proteome Database is a National Science Foundation-funded project to determine the biological function of each protein in plants. It includes data for two plants that are widely studied in molecular biology, Arabidopsis thaliana and maize (Zea mays). Initially the project was limited to plant plastids, under the name of the Plastid PDB, but was expanded and renamed Plant PDB in November 2007. See also Proteome References External links Plant Proteome Database home page Plant physiology Government databases in the United States Biological databases
https://en.wikipedia.org/wiki/Nuclear%20matrix
In biology, the nuclear matrix is the network of fibres found throughout the inside of a cell nucleus after a specific method of chemical extraction. According to some it is somewhat analogous to the cell cytoskeleton. In contrast to the cytoskeleton, however, the nuclear matrix has been proposed to be a dynamic structure. Along with the nuclear lamina, it supposedly aids in organizing the genetic information within the cell. The exact function of this structure is still disputed, and its very existence has been called into question. Evidence for such a structure was recognised as long ago as 1948, and consequently many proteins associated with the matrix have been discovered. The presence of intra-cellular proteins is common ground, and it is agreed that proteins such as the Scaffold, or Matrix Associated Proteins (SAR or MAR) have some role in the organisation of chromatin in the living cell. There is evidence that the nuclear matrix is involved in regulation of gene expression in Arabidopsis thaliana. Whenever a similar structure can actually be found in living cells remains a topic of discussion. According to some sources, most, if not all proteins found in nuclear matrix are the aggregates of proteins of structures that can be found in the nucleus of living cells. Such structures are nuclear lamina, which consist of proteins termed lamins which can be also found in the nuclear matrix. Validity of nuclear matrix For a long time the question whether a polymer meshwork,
https://en.wikipedia.org/wiki/Tarsem%20Singh
Tarsem Singh Dhandwar (born 26 May 1961), known professionally as Tarsem, is an Indian director who has worked on films, music videos, and commercials. He directed The Cell (2000), The Fall (2006, also screenwriter and producer), Immortals (2011), Mirror Mirror (2012), and Self/less (2015). Early life Tarsem was born in Jalandhar, Punjab to a Punjabi Sikh family. His father was an aircraft engineer. He attended Bishop Cotton School in Shimla, Hans Raj College in Delhi, and is a graduate of the Art Center College of Design in Pasadena, California. Career Tarsem began his career by directing music videos, including those of "Hold On" by En Vogue, "Sweet Lullaby" by Deep Forest and R.E.M.'s "Losing My Religion", the latter of which won Best Music Video, Short Form at the 1992 Grammy Awards. He has directed commercials for brands such as Nike and Coca-Cola. Tarsem's feature film directorial debut was The Cell (2000), starring Jennifer Lopez. In 2003, Tarsem directed one of the most elaborate Pepsi commercials to date. It combined a gladiator theme with Queen's "We Will Rock You". The commercial starred Enrique Iglesias in the version of the commercial aired in Europe and North America and Amr Diab in the version aired in the Arab world. Tarsem's second film, The Fall, debuted at the 2006 Toronto International Film Festival and was released in theatres in the United States in 2008. His third film was 2011's Immortals. He directed an adaptation of the Brothers Grimm story of
https://en.wikipedia.org/wiki/FINO
In computer science, FINO is a humorous scheduling algorithm. It is an acronym for first in, never out as opposed to traditional first in, first out (FIFO) and last in, first out (LIFO) algorithms. A similar acronym is "FISH", for first in, still here. FINO works by withholding all scheduled tasks permanently. No matter how many tasks are scheduled at any time, no task ever actually takes place. A stateful FINO queue can be used to implement a memory leak. The first mention of FINO appears in the Signetics 25120 write-only memory joke datasheet. See also Bit bucket Black hole (networking) Null route Write-only memory References Scheduling algorithms Computer humor
https://en.wikipedia.org/wiki/Enterochromaffin%20cell
Enterochromaffin (EC) cells (also known as Kulchitsky cells) are a type of enteroendocrine cell, and neuroendocrine cell. They reside alongside the epithelium lining the lumen of the digestive tract and play a crucial role in gastrointestinal regulation, particularly intestinal motility and secretion. They were discovered by Nikolai Kulchitsky. EC cells modulate neuron signalling in the enteric nervous system (ENS) via the secretion of the neurotransmitter serotonin and other peptides. As enteric afferent and efferent nerves do not protrude into the intestinal lumen, EC cells act as a form of sensory transduction. Serotonin in the ENS acts in synergy with other digestive hormones to regulate sensory and motor gastrointestinal reflexes. EC cells respond to both chemical and neurological stimuli. They are also reactive to mechanosensation, which is the case in the peristaltic reflex of the gut, and can be stimulated by a bolus moving through the bowel. Upon activation, EC cells release serotonin to act upon serotonin receptors on ENS neurons. Dependent on concentration, serotonin can then modulate peristaltic contraction and secretion through activation of smooth muscle and glands, respectively. Pulmonary neuroendocrine cells in the respiratory tract are known as bronchial Kulchitsky cells. Structure EC cells are small polygonal cells located in the crypts between intestinal villi. They are discriminated from other cells of the gastrointestinal epithelial crypts by the pre
https://en.wikipedia.org/wiki/Neuregulin
Neuregulins are a family of four structurally related proteins that are part of the EGF family of proteins. These proteins have been shown to have diverse functions in the development of the nervous system and play multiple essential roles in vertebrate embryogenesis including: cardiac development, Schwann cell and oligodendrocyte differentiation, some aspects of neuronal development, as well as the formation of neuromuscular synapses. Included in the family are heregulin; neu differentiation factor; acetylcholine receptor synthesis stimulator; glial growth factor; and sensory and motor-neuron derived factor. Multiple family members are generated by alternate splicing or by use of several cell type-specific transcription initiation sites. In general, they bind to and activate the erbB family of receptor tyrosine kinases (erbB2 (HER2), erbB3 (HER3), and erbB4 (HER4)), functioning both as heterodimers and homodimers. Neuregulin family members The neuregulin family includes: Neuregulin 1 (NRG1), with numerous discovered isoforms stemming from alternative splicing: Type I NRG1; alternative names: Heregulin, NEU differentiation factor (NDF), or acetylcholine receptor inducing activity (ARIA) Type II NRG1; alternative name: Glial Growth Factor-2 (GGF2); Type III NRG1; alternative name: Sensory and motor neuron-derived factor (SMDF); Type IV NRG1; Type V NRG1; Type VI NRG1; Types IV-VI are proteins with 3 novel N-terminal domains identified in 2004. Neuregulin 2 (NRG2); N
https://en.wikipedia.org/wiki/David%20Lee%20%28physicist%29
David Morris Lee (born January 20, 1931) is an American physicist who shared the 1996 Nobel Prize in Physics with Robert C. Richardson and Douglas Osheroff "for their discovery of superfluidity in helium-3." Lee is professor emeritus of physics at Cornell University and distinguished professor of physics at Texas A&M University. Personal life Lee was born and raised in Rye, New York. His parents, Annette (Franks), a teacher, and Marvin Lee, an electrical engineer, were children of Jewish immigrants from England and Lithuania. He graduated from Harvard University in 1952 and then joined the U.S. Army for 22 months. After being discharged from the army, he obtained a master's degree from the University of Connecticut. In 1955 Lee entered the Ph.D. program at Yale University where he worked under Henry A. Fairbank in the low-temperature physics group, doing experimental research on liquid 3He. After graduating from Yale in 1959, Lee took a job at Cornell University, where he was responsible for setting up the new Laboratory of Atomic and Solid State Physics. Shortly after arriving at Cornell he met his future wife, Dana, then a PhD student in another department; the couple went on to have two sons. Lee moved his laboratory from Cornell to Texas A&M University on November 16, 2009. Work The work that led to Lee's Nobel Prize was performed in the early 1970s. Lee, together with Robert C. Richardson and graduate student, Doug Osheroff used a Pomeranchuk cell to investigate t
https://en.wikipedia.org/wiki/Neural%20crest
Neural crest cells are a temporary group of cells that arise from the embryonic ectoderm germ layer, and in turn give rise to a diverse cell lineage—including melanocytes, craniofacial cartilage and bone, smooth muscle, peripheral and enteric neurons and glia. After gastrulation, neural crest cells are specified at the border of the neural plate and the non-neural ectoderm. During neurulation, the borders of the neural plate, also known as the neural folds, converge at the dorsal midline to form the neural tube. Subsequently, neural crest cells from the roof plate of the neural tube undergo an epithelial to mesenchymal transition, delaminating from the neuroepithelium and migrating through the periphery where they differentiate into varied cell types. The emergence of neural crest was important in vertebrate evolution because many of its structural derivatives are defining features of the vertebrate clade. Underlying the development of neural crest is a gene regulatory network, described as a set of interacting signals, transcription factors, and downstream effector genes that confer cell characteristics such as multipotency and migratory capabilities. Understanding the molecular mechanisms of neural crest formation is important for our knowledge of human disease because of its contributions to multiple cell lineages. Abnormalities in neural crest development cause neurocristopathies, which include conditions such as frontonasal dysplasia, Waardenburg–Shah syndrome, and
https://en.wikipedia.org/wiki/Pseudorandom%20binary%20sequence
A pseudorandom binary sequence (PRBS), pseudorandom binary code or pseudorandom bitstream is a binary sequence that, while generated with a deterministic algorithm, is difficult to predict and exhibits statistical behavior similar to a truly random sequence. PRBS generators are used in telecommunication, such as in analog-to-information conversion, but also in encryption, simulation, correlation technique and time-of-flight spectroscopy. The most common example is the maximum length sequence generated by a (maximal) linear feedback shift register (LFSR). Other examples are Gold sequences (used in CDMA and GPS), Kasami sequences and JPL sequences, all based on LFSRs. In telecommunications, pseudorandom binary sequences are known as pseudorandom noise codes (PN or PRN codes) due to their application as pseudorandom noise. Details A binary sequence (BS) is a sequence of bits, i.e. for . A BS consists of ones and zeros. A BS is a pseudorandom binary sequence (PRBS) if its autocorrelation function, given by has only two values: where is called the duty cycle of the PRBS, similar to the duty cycle of a continuous time signal. For a maximum length sequence, where , the duty cycle is 1/2. A PRBS is 'pseudorandom', because, although it is in fact deterministic, it seems to be random in a sense that the value of an element is independent of the values of any of the other elements, similar to real random sequences. A PRBS can be stretched to infinity by repeating it af
https://en.wikipedia.org/wiki/Rapakivi%20granite
Rapakivi granite is a hornblende-biotite granite containing large round crystals of orthoclase each with a rim of oligoclase (a variety of plagioclase). The name has come to be used most frequently as a textural term where it implies plagioclase rims around orthoclase in plutonic rocks. Rapakivi is a Finnish compound of "rapa" (meaning "mud" or "sand") and "kivi" (meaning "rock"), because the different heat expansion coefficients of the component minerals make exposed rapakivi crumble easily into sand. Rapakivi was first described by Finnish petrologist Jakob Sederholm in 1891. Since then, southern Finland's rapakivi granite intrusions have been the type locality of this variety of granite. Occurrence Rapakivi is a fairly uncommon type of granite, but has been described from localities in North and South America (Illescas Batholith, Uruguay, Rondônia, Brazil) parts of the Baltic Shield, southern Greenland, southern Africa, India and China. Most of these examples are found within Proterozoic metamorphic belts, although both Archaean and Phanerozoic examples are known. Formation Rapakivi granites have formation ages from Archean to recent and are usually attributed to anorogenic tectonic settings. They have formed in shallow (a few km deep) sills of up to 10 km thickness. Rapakivi granites are often found associated with intrusions of anorthosite, norite, charnockite and mangerite. It has been suggested that the entire suite results from the fractional crystallization of
https://en.wikipedia.org/wiki/Structural%20equation%20modeling
Structural equation modeling (SEM) is a diverse set of methods used by scientists doing both observational and experimental research. SEM is used mostly in the social and behavioral sciences but it is also used in epidemiology, business, and other fields. A definition of SEM is difficult without reference to technical language, but a good starting place is the name itself. SEM involves a model representing how various aspects of some phenomenon are thought to causally connect to one another. Structural equation models often contain postulated causal connections among some latent variables (variables thought to exist but which can't be directly observed). Additional causal connections link those latent variables to observed variables whose values appear in a data set. The causal connections are represented using equations but the postulated structuring can also be presented using diagrams containing arrows as in Figures 1 and 2. The causal structures imply that specific patterns should appear among the values of the observed variables. This makes it possible to use the connections between the observed variables' values to estimate the magnitudes of the postulated effects, and to test whether or not the observed data are consistent with the requirements of the hypothesized causal structures. The boundary between what is and is not a structural equation model is not always clear but SE models often contain postulated causal connections among a set of latent variables (variable
https://en.wikipedia.org/wiki/Quark%20model
In particle physics, the quark model is a classification scheme for hadrons in terms of their valence quarks—the quarks and antiquarks that give rise to the quantum numbers of the hadrons. The quark model underlies "flavor SU(3)", or the Eightfold Way, the successful classification scheme organizing the large number of lighter hadrons that were being discovered starting in the 1950s and continuing through the 1960s. It received experimental verification beginning in the late 1960s and is a valid effective classification of them to date. The model was independently proposed by physicists Murray Gell-Mann, who dubbed them "quarks" in a concise paper, and George Zweig, who suggested "aces" in a longer manuscript. André Petermann also touched upon the central ideas from 1963 to 1965, without as much quantitative substantiation. Today, the model has essentially been absorbed as a component of the established quantum field theory of strong and electroweak particle interactions, dubbed the Standard Model. Hadrons are not really "elementary", and can be regarded as bound states of their "valence quarks" and antiquarks, which give rise to the quantum numbers of the hadrons. These quantum numbers are labels identifying the hadrons, and are of two kinds. One set comes from the Poincaré symmetry—JPC, where J, P and C stand for the total angular momentum, P-symmetry, and C-symmetry, respectively. The other set is the flavor quantum numbers such as the isospin, strangeness, charm, and
https://en.wikipedia.org/wiki/The%20Crystal%20Prison
The Crystal Prison is a dark fantasy novel for children by British author Robin Jarvis. It is the second book in The Deptford Mice trilogy, first published in the United Kingdom in 1989 by Macdonald & Company, London. In 2001, it was published by SeaStar Books in the United States. The book continues the story of the young house mouse Audrey after she and her friends have defeated the evil cat Jupiter, lord of the sewer rats. Plot The story picks up shortly after the last book left off. Albino mouse Oswald Chitter is deathly ill, having caught an infection during his time in the Deptford sewers battling the villainous cat Jupiter with his friends. In caring for him, Oswald's parents have become sick as well. They are now being tended to by their friends the Browns, city mouse Piccadilly, and Oswald's fieldmouse cousin Twit. Midshipmouse Thomas Triton arrives with news that the Starwife, the wise and ancient queen of the squirrels, has summoned Audrey to her chambers so she can hear the story of Jupiter's downfall firsthand. While there, the Starwife reveals the main reason for summoning Audrey: the rat Madame Akkikuyu was found wandering aimlessly in Greenwich Park by her sentries. A phony fortune teller who once served Jupiter, Akkikuyu lost her mind when she discovered he was a cat. Now she is harmless, and the Starwife believes it best if Audrey, whom Akkikuyu considers her close friend, accompanies the rat to Twit's home of Fennywolde, a rural field. There she can live o
https://en.wikipedia.org/wiki/Expression%20cassette
An expression cassette is a distinct component of vector DNA consisting of a gene and regulatory sequence to be expressed by a transfected cell. In each successful transformation, the expression cassette directs the cell's machinery to make RNA and protein(s). Some expression cassettes are designed for modular cloning of protein-encoding sequences so that the same cassette can easily be altered to make different proteins. An expression cassette is composed of one or more genes and the sequences controlling their expression. An expression cassette comprises three components: a promoter sequence, an open reading frame, and a 3' untranslated region that, in eukaryotes, usually contains a polyadenylation site. Different expression cassettes can be transfected into different organisms including bacteria, yeast, plants, and mammalian cells as long as the correct regulatory sequences are used. See also Expression vector Gene cassette References DNA
https://en.wikipedia.org/wiki/PHF
PHF is a three letter acronym meaning: Paired Helical Filaments, a term for aggregations of protein in the brain, in conditions such as Alzheimer's disease The Pakistan Hockey Federation, national governing body for field hockey Patrick Henry Field, the IATA code for the Newport News/Williamsburg International Airport Peak Hour Factor, a traffic flow characteristic Perfect Hair Forever, an American animated television comedy Perfect Hair Forever (band), an alternative rock band from Auckland, New Zealand Perfect hash function, a set of hash functions which generate no collisions. Potentially Hazardous Food, a food safety classification Potomac Horse Fever, an illness affecting horses caused by Neorickettsia risticii. Premier Hockey Federation, a professional women's ice hockey league located in the United States & Canada. Public Health Foundation Putting Hartlepool First, a localist English political party based in Hartlepool.
https://en.wikipedia.org/wiki/Regularization%20%28mathematics%29
In mathematics, statistics, finance, computer science, particularly in machine learning and inverse problems, regularization is a process that changes the result answer to be "simpler". It is often used to obtain results for ill-posed problems or to prevent overfitting. Although regularization procedures can be divided in many ways, the following delineation is particularly helpful: Explicit regularization is regularization whenever one explicitly adds a term to the optimization problem. These terms could be priors, penalties, or constraints. Explicit regularization is commonly employed with ill-posed optimization problems. The regularization term, or penalty, imposes a cost on the optimization function to make the optimal solution unique. Implicit regularization is all other forms of regularization. This includes, for example, early stopping, using a robust loss function, and discarding outliers. Implicit regularization is essentially ubiquitous in modern machine learning approaches, including stochastic gradient descent for training deep neural networks, and ensemble methods (such as random forests and gradient boosted trees). In explicit regularization, independent of the problem or model, there is always a data term, that corresponds to a likelihood of the measurement and a regularization term that corresponds to a prior. By combining both using Bayesian statistics, one can compute a posterior, that includes both information sources and therefore stabilizes the est
https://en.wikipedia.org/wiki/Lithium%20acetate
Lithium acetate (CH3COOLi) is a salt of lithium and acetic acid. It is often abbreviated as LiOAc. Uses Lithium acetate is used in the laboratory as buffer for gel electrophoresis of DNA and RNA. It has a lower electrical conductivity and can be run at higher speeds than can gels made from TAE buffer (5-30V/cm as compared to 5-10V/cm). At a given voltage, the heat generation and thus the gel temperature is much lower than with TAE buffers, therefore the voltage can be increased to speed up electrophoresis so that a gel run takes only a fraction of the usual time. Downstream applications, such as isolation of DNA from a gel slice or Southern blot analysis, work as expected when using lithium acetate gels. Lithium boric acid or sodium boric acid are usually preferable to lithium acetate or TAE when analyzing smaller fragments of DNA (less than 500 bp) due to the higher resolution of borate-based buffers in this size range as compared to acetate buffers. Lithium acetate is also used to permeabilize the cell wall of yeast for use in DNA transformation. It is believed that the beneficial effect of LiOAc is caused by its chaotropic effect; denaturing DNA, RNA and proteins. References Acetates Lithium salts Organolithium compounds
https://en.wikipedia.org/wiki/List%20of%20British%20weapon%20L%20numbers
The L number ("L" standing for Land Service) or weapon identity number system is a numerical designation system used for the type classification of British Army weapons and related stores. The L number in isolation is not a unique identifier; the L1 designation alone is used for a rifle and its corresponding bayonet and blank-firing attachment, a machine gun, a tank gun, a sighting telescope, an anti-riot grenade, three separate rocket systems, a necklace demolition charge, a hand-thrown flare, a fuze setter head, and two separate types of user-filled demolition charge among other stores, while the L10 designation was used for three separate calibres of blank cartridge. Rather, the number is used in conjunction with a description, e.g. "Rifle, 7.62mm, L1A1" or "L1A1 7.62mm Rifle". The A number following the L number refers to the particular version of a piece of equipment; unlike some similar designation systems used by other countries where an A number is only used for subsequent versions of equipment, an A1 designation is always used for the first version to be officially adopted. Stores coming into Army service began receiving Land Service designations in 1954, replacing the old number-and-mark system of designations. Some weapons such as the AR-15 and M16A2 rifles, C3 Non-Metallic Anti-Personnel Mine, M18A1 Anti-Personnel Mine, M79 grenade launcher, M6-895 and M6-640 mortars, were not given L numbers and are referred to in official documentation by their manufacturer's d
https://en.wikipedia.org/wiki/Ceiling%20effect%20%28statistics%29
The "ceiling effect" is one type of scale attenuation effect; the other scale attenuation effect is the "floor effect". The ceiling effect is observed when an independent variable no longer has an effect on a dependent variable, or the level above which variance in an independent variable is no longer measurable. The specific application varies slightly in differentiating between two areas of use for this term: pharmacological or statistical. An example of use in the first area, a ceiling effect in treatment, is pain relief by some kinds of analgesic drugs, which have no further effect on pain above a particular dosage level (see also: ceiling effect in pharmacology). An example of use in the second area, a ceiling effect in data-gathering, is a survey that groups all respondents into income categories, not distinguishing incomes of respondents above the highest level measured in the survey instrument. The maximum income level able to be reported creates a "ceiling" that results in measurement inaccuracy, as the dependent variable range is not inclusive of the true values above that point. The ceiling effect can occur any time a measure involves a set range in which a normal distribution predicts multiple scores at or above the maximum value for the dependent variable. Data-gathering A ceiling effect in data-gathering, when variance in a dependent variable is not measured or estimated above a certain level, is a commonly encountered practical issue in gathering data in man
https://en.wikipedia.org/wiki/Sodium%20perchlorate
Sodium perchlorate is the inorganic compound with the chemical formula NaClO4. It is a white crystalline, hygroscopic solid that is highly soluble in water and in alcohol. It is usually encountered as the monohydrate. The compound is noteworthy as the most water-soluble of the common perchlorate salts. Sodium perchlorate and other perchlorates has been found on the planet Mars, first detected by the NASA probe Phoenix in 2009. This was later confirmed by spectral analysis by the Mars Reconnaissance Orbiter in 2015 of what is thought to be brine seeps which may be the first evidence of flowing liquid water containing hydrated salts on Mars. Selected properties Its heat of formation is −382.75 kJ/mol, i.e. it is thermally stable up to high temperatures. At 490 °C it undergoes thermal decomposition, producing sodium chloride and dioxygen. It crystallizes in the rhombic crystal system. Uses Sodium perchlorate is the precursor to many other perchlorate salts, often taking advantage of their low solubility relative to NaClO4 (209 g/100 mL at 25 °C). Perchloric acid is made by treating NaClO4 with HCl. Ammonium perchlorate and potassium perchlorate, of interest in rocketry and pyrotechnics, are prepared by double decomposition from a solution of sodium perchlorate and ammonium chloride or potassium chloride, respectively. Laboratory applications Solutions of NaClO4 are often used as an unreactive electrolyte. It is used in standard DNA extraction and hybridization reactions
https://en.wikipedia.org/wiki/One-pass%20compiler
In computer programming, a one-pass compiler is a compiler that passes through the parts of each compilation unit only once, immediately translating each part into its final machine code. This is in contrast to a multi-pass compiler which converts the program into one or more intermediate representations in steps between source code and machine code, and which reprocesses the entire compilation unit in each sequential pass. This refers to the logical functioning of the compiler, not to the actual reading of the source file once only. For instance, the source file could be read once into temporary storage but that copy could then be scanned many times. The IBM 1130 Fortran compiler stored the source in memory and used many passes; by contrast the assembler, on systems lacking a disc storage unit, required that the source deck of cards be presented twice to the card reader/punch. Properties One-pass compilers are smaller and faster than multi-pass compilers. One-pass compilers are unable to generate as efficient programs as multi-pass compilers due to the limited scope of available information. Many effective compiler optimizations require multiple passes over a basic block, loop (especially nested loops), subroutine, or entire module. Some require passes over an entire program. Some programming languages simply cannot be compiled in a single pass, as a result of their design. For example PL/I allows data declarations to be placed anywhere within a program, specifically
https://en.wikipedia.org/wiki/Football%20records%20and%20statistics%20in%20Sweden
This article lists various Swedish football records for the various Swedish football leagues and competitions and the Sweden national team. National team Men's national team Largest victory: 12–0 vs. Latvia, 29 May 1927 Largest loss: 1–12 vs. England Amateur, 20 October 1908 Most appearances, career: 148 Anders Svensson (1999–2013) Most appearances, consecutive: 45 Orvar Bergmark (1956–62) Most goals scored, career: 62 Zlatan Ibrahimović (2001–16) Most penalty goals scored, career: 7 Bo Larsson (1964–74) Most hat-tricks, career: 9 Taym Aljumailie (1924–32) Fastest goal: 11 seconds Hjalmar Lorichs vs. Finland, 27 June 1912 Swedish Champions Most championships: 22 Malmö FF 1943–44, 1948–49, 1949–50, 1950–51, 1952–53, 1965, 1967, 1970, 1971, 1974, 1975, 1977, 1986, 1988, 2004, 2010, 2013, 2014, 2016, 2017, 2020, 2021 Most championships, consecutive: 4 Örgryte IS 1896, 1897, 1898, 1899 1904, 1905, 1906, 1907 IFK Norrköping 1944–45, 1945–46, 1946–47, 1947–48 IFK Göteborg 1993, 1994, 1995, 1996 Allsvenskan Most championships: 25 Malmö FF 1943–44, 1948–49, 1949–50, 1950–51, 1952–53, 1965, 1967, 1970, 1971, 1974, 1975, 1977, 1985, 1986, 1987, 1988, 1989, 2004, 2010, 2013, 2014, 2016, 2017, 2020, 2021 Most championships, consecutive: 5 Malmö FF 1985, 1986, 1987, 1988, 1989 Most wins, season: 21 Malmö FF (2010) Played 30, won 21, drew 4, lost 5 Fewest wins, season: 0 Billingsfors IK Played 22, won 0, drew 3, lost 19 Wins, consecutive: 23 Malmö FF (1949–
https://en.wikipedia.org/wiki/Exact%20differential%20equation
In mathematics, an exact differential equation or total differential equation is a certain kind of ordinary differential equation which is widely used in Physics and engineering. Definition Given a simply connected and open subset D of and two functions I and J which are continuous on D, an implicit first-order ordinary differential equation of the form is called an exact differential equation if there exists a continuously differentiable function F, called the potential function, so that and An exact equation may also be presented in the following form: where the same constraints on I and J apply for the differential equation to be exact. The nomenclature of "exact differential equation" refers to the exact differential of a function. For a function , the exact or total derivative with respect to is given by Example The function given by is a potential function for the differential equation First order exact differential equations Identifying first order exact differential equations Let the functions , , , and , where the subscripts denote the partial derivative with respect to the relative variable, be continuous in the region . Then the differential equation is exact if and only if That is, there exists a function , called a potential function, such that So, in general: Proof The proof has two parts. First, suppose there is a function such that It then follows that Since and are continuous, then and are also continuous which guarantees their eq
https://en.wikipedia.org/wiki/Load%20cell
A load cell converts a force such as tension, compression, pressure, or torque into a signal (electrical, pneumatic or hydraulic pressure, or mechanical displacement indicator) that can be measured and standardized. It is a force transducer. As the force applied to the load cell increases, the signal changes proportionally. The most common types of load cells are pneumatic, hydraulic, and strain gauge types for industrial applications. Typical non-electronic bathroom scales are a widespread example of a mechanical displacement indicator where the applied weight (force) is indicated by measuring the deflection of springs supporting the load platform, technically a "load cell". Strain gauge load cell Strain gauge load cells are the kind most often found in industrial settings. It is ideal as it is highly accurate, versatile, and cost-effective. Structurally, a load cell has a metal body to which strain gauges have been secured.  The body is usually made of aluminum, alloy steel, or stainless steel which makes it very sturdy but also minimally elastic. This elasticity gives rise to the term "spring element", referring to the body of the load cell.  When force is exerted on the load cell, the spring element is slightly deformed, and unless overloaded, always returns to its original shape. As the spring element deforms, the strain gauges also change shape. The resulting alteration to the resistance in the strain gauges can be measured as voltage. The change in voltage is proporti
https://en.wikipedia.org/wiki/Pin%20Oak%20Fountain
The Pin Oak Fountain was built in the U.S. state of West Virginia by the West Virginia State Road Commission and local artisans in 1932 on land given by H.R. Edeburn. The crystal quartz used in construction was quarried from behind nearby Bloomery Iron Furnace on Diamond Ridge, and the stone from the hillside behind the fountain. The fountain's spring water is gravity fed from the hill above and continues to supply area residents and travelers. The fountain is a popular site for picnics, dances, courting, and auctions. Pin Oak Fountain was restored in 1988 and is maintained by the Pin Oak Extension Homemakers Club. The fountain and its historical marker are located on West Virginia Route 29, eight miles southeast of Paw Paw in the community of Pin Oak. It was listed on the National Register of Historic Places in 2016. Image gallery External links Tourist attractions in Hampshire County, West Virginia Landmarks in West Virginia Natural history of West Virginia Buildings and structures in Hampshire County, West Virginia National Register of Historic Places in Hampshire County, West Virginia
https://en.wikipedia.org/wiki/Lockhart%E2%80%93Martinelli%20parameter
The Lockhart–Martinelli parameter () is a dimensionless number used in internal two-phase flow calculations. It expresses the liquid fraction of a flowing fluid. Its main application is in two-phase pressure drop and boiling/condensing heat transfer calculations. It is defined as: where is the liquid phase mass flowrate; is the gas phase mass flowrate; is the gas density; is the liquid density. See also Wet gas References Dimensionless numbers
https://en.wikipedia.org/wiki/The%20Dancers%20at%20the%20End%20of%20Time
The Dancers at the End of Time is a series of science fiction novels and short stories written by Michael Moorcock, the setting of which is the End of Time, an era "where entropy is king and the universe has begun collapsing upon itself". The inhabitants of this era are immortal decadents, who create flights of fancy via the use of power rings that draw on energy devised and stored by their ancestors millions of years prior. Time travel is possible, and throughout the series various points in time are visited and revisited. Space travellers are also common, but most residents of the End of Time find leaving the planet distasteful and clichéd. The title of the series is itself taken from a poem by a fictitious 19th-century poet, Ernest Wheldrake, which Mrs. Amelia Underwood quotes in The End of All Songs. "Ernest Wheldrake" had been a pseudonym used by Algernon Charles Swinburne. The original trilogy (An Alien Heat, The Hollow Lands, and The End of All Songs) was published between 1972 and 1976. The trilogy purports to tell the last love story in human history. Other stories in this sequence include The Transformation of Miss Mavis Ming (also known as A Messiah at the End of Time) which is a rewrite of the novella Constant Fire. Several short stories, some of which were included in the collection Legends from the End of Time, were published in New Worlds 7–10 (the paperback revival of the magazine). Short stories featuring Elric ("Elric at the End of Time"), and Jerry Corneli
https://en.wikipedia.org/wiki/Solar%20analog
Solar-type stars, solar analogs (also analogues), and solar twins are stars that are particularly similar to the Sun. The stellar classification is a hierarchy with solar twin being most like the Sun followed by solar analog and then solar-type. Observations of these stars are important for understanding better the properties of the Sun in relation to other stars and the habitability of planets. By similarity to the Sun Defining the three categories by their similarity to the Sun reflects the evolution of astronomical observational techniques. Originally, solar-type was the closest that similarity to the Sun could be defined. Later, more precise measurement techniques and improved observatories allowed for greater precision of key details like temperature, enabling the creation of a solar analog category for stars that were particularly similar to the Sun. Later still, continued improvements in precision allowed for the creation of a solar-twin category for near-perfect matches. Similarity to the Sun allows for checking derived quantities—such as temperature, which is derived from the color index—against the Sun, the only star whose temperature is confidently known. For stars that are not similar to the Sun, this cross-checking cannot be done. Solar-type These stars are broadly similar to the Sun. They are main-sequence stars with a B−V color between 0.48 and 0.80, the Sun having a B−V color of 0.65. Alternatively, a definition based on spectral type can be used, such a
https://en.wikipedia.org/wiki/Tryptase
Tryptase (, ) is the most abundant secretory granule-derived serine proteinase contained in mast cells and has been used as a marker for mast cell activation. Club cells contain tryptase, which is believed to be responsible for cleaving the hemagglutinin surface protein of influenza A virus, thereby activating it and causing the symptoms of flu. Nomenclature Tryptase is also known by mast cell tryptase, mast cell protease II, skin tryptase, lung tryptase, pituitary tryptase, mast cell neutral proteinase, mast cell serine proteinase II, mast cell proteinase II, mast cell serine proteinase tryptase, rat mast cell protease II, and tryptase M. Clinical use Serum levels are normally less than 11.5 ng/mL. Elevated levels of serum tryptase occur in both anaphylactic and anaphylactoid reactions, but a negative test does not exclude anaphylaxis. Tryptase is less likely to be elevated in food allergy reactions as opposed to other causes of anaphylaxis. Serum tryptase levels are also elevated in and used as one indication suggesting the presence of eosinophilic leukemias due to genetic mutations resulting in the formation of FIP1L1-PDGFRA fusion genes or the presence of systemic mastocytosis. Physiology Tryptase is involved with allergenic response and is suspected to act as a mitogen for fibroblast lines. Tryptase may use the morpheein model of allosteric regulation. Mast cell tryptase-6 is involved in Trichinella spiralis infection in mice through linking adaptive and innate
https://en.wikipedia.org/wiki/Two-hybrid%20screening
Two-hybrid screening (originally known as yeast two-hybrid system or Y2H) is a molecular biology technique used to discover protein–protein interactions (PPIs) and protein–DNA interactions by testing for physical interactions (such as binding) between two proteins or a single protein and a DNA molecule, respectively. The premise behind the test is the activation of downstream reporter gene(s) by the binding of a transcription factor onto an upstream activating sequence (UAS). For two-hybrid screening, the transcription factor is split into two separate fragments, called the DNA-binding domain (DBD or often also abbreviated as BD) and activating domain (AD). The BD is the domain responsible for binding to the UAS and the AD is the domain responsible for the activation of transcription. The Y2H is thus a protein-fragment complementation assay. History Pioneered by Stanley Fields and Ok-Kyu Song in 1989, the technique was originally designed to detect protein–protein interactions using the Gal4 transcriptional activator of the yeast Saccharomyces cerevisiae. The Gal4 protein activated transcription of a gene involved in galactose utilization, which formed the basis of selection. Since then, the same principle has been adapted to describe many alternative methods, including some that detect protein–DNA interactions or DNA-DNA interactions, as well as methods that use different host organisms such as Escherichia coli or mammalian cells instead of yeast. Basic premise The ke
https://en.wikipedia.org/wiki/Improved%20Touring
Improved Touring is a category of classifications for cars in amateur road racing defined by the Sports Car Club of America. The class is used by other sanctioning bodies with compatible rules, such as the International Conference of Sports Car Clubs. The classifications within the Improved Touring group define cars that will run together competitively in a road race. While cars in different classifications may be on the track simultaneously, the only positioning that matters is between cars of the same classification. The rules for the class include the General Competition Rules (GCR), a section of the SCCA rulebook that defines the basic setup and preparation for cars in any class of SCCA racing. Improved Touring cars are also subject to the rules in the Improved Touring Category Section (ITCS) of the rulebook, which define the specific classes and provide the class-specific rules. GCR Rules The rules from the GCR applying to Improved Touring cars mostly involve safety and basic setup. The GCR specifies the construction, fabrication, and material used in installing a roll-cage, for example. It also explains the rules of the road during racing events, including the flags and right of way rules for passing maneuvers. Improved Touring is intended to provide a low barrier to entry by using a set of rules which limit modification of the cars while keeping the cars safe for competition. To this end, the cars are production-based models built after 1964 with a reasonable amou
https://en.wikipedia.org/wiki/Autoantibody
An autoantibody is an antibody (a type of protein) produced by the immune system that is directed against one or more of the individual's own proteins. Many autoimmune diseases (notably lupus erythematosus) are associated with such antibodies. Production Antibodies are produced by B cells in two ways: (i) randomly, and (ii) in response to a foreign protein or substance within the body. Initially, one B cell produces one specific kind of antibody. In either case, the B cell is allowed to proliferate or is killed off through a process called clonal deletion. Normally, the immune system is able to recognize and ignore the body's own healthy proteins, cells, and tissues, and to not overreact to non-threatening substances in the environment, such as foods. Sometimes, the immune system ceases to recognize one or more of the body's normal constituents as "self", leading to production of pathological autoantibodies. Autoantibodies may also play a nonpathological role; for instance they may help the body to destroy cancers and to eliminate waste products. The role of autoantibodies in normal immune function is also a subject of scientific research. Cause The causes of autoantibody production are varied and not well understood. It is thought that some autoantibody production is due to a genetic predisposition combined with an environmental trigger, such as a viral illness or a prolonged exposure to certain toxic chemicals. There is generally not a direct genetic link however. Whi
https://en.wikipedia.org/wiki/Factor%20graph
A factor graph is a bipartite graph representing the factorization of a function. In probability theory and its applications, factor graphs are used to represent factorization of a probability distribution function, enabling efficient computations, such as the computation of marginal distributions through the sum–product algorithm. One of the important success stories of factor graphs and the sum–product algorithm is the decoding of capacity-approaching error-correcting codes, such as LDPC and turbo codes. Factor graphs generalize constraint graphs. A factor whose value is either 0 or 1 is called a constraint. A constraint graph is a factor graph where all factors are constraints. The max-product algorithm for factor graphs can be viewed as a generalization of the arc-consistency algorithm for constraint processing. Definition A factor graph is a bipartite graph representing the factorization of a function. Given a factorization of a function , where , the corresponding factor graph consists of variable vertices , factor vertices , and edges . The edges depend on the factorization as follows: there is an undirected edge between factor vertex and variable vertex if . The function is tacitly assumed to be real-valued: . Factor graphs can be combined with message passing algorithms to efficiently compute certain characteristics of the function , such as the marginal distributions. Examples Consider a function that factorizes as follows: , with a corresponding factor
https://en.wikipedia.org/wiki/Rieske%20protein
Rieske proteins are iron–sulfur protein (ISP) components of cytochrome bc1 complexes and cytochrome b6f complexes and are responsible for electron transfer in some biological systems. John S. Rieske and co-workers first discovered the protein and in 1964 isolated an acetylated form of the bovine mitochondrial protein. In 1979 Trumpower's lab isolated the "oxidation factor" from bovine mitochondria and showed it was a reconstitutively-active form of the Rieske iron-sulfur protein It is a unique [2Fe-2S] cluster in that one of the two Fe atoms is coordinated by two histidine residues rather than two cysteine residues. They have since been found in plants, animals, and bacteria with widely ranging electron reduction potentials from -150 to +400 mV. Biological function Ubiquinol-cytochrome-c reductase (also known as bc1 complex or complex III) is an enzyme complex of bacterial and mitochondrial oxidative phosphorylation systems. It catalyses the oxidation-reduction reaction of the mobile components ubiquinol and cytochrome c, contributing to an electrochemical potential difference across the mitochondrial inner or bacterial membrane, which is linked to ATP synthesis. The complex consists of three subunits in most bacteria, and nine in mitochondria: both bacterial and mitochondrial complexes contain cytochrome b and cytochrome c1 subunits, and an iron–sulfur 'Rieske' subunit, which contains a high potential 2Fe-2S cluster. The mitochondrial form also includes six other subuni
https://en.wikipedia.org/wiki/Ventrolateral%20preoptic%20nucleus
The ventrolateral preoptic nucleus (VLPO), also known as the intermediate nucleus of the preoptic area (IPA), is a small cluster of neurons situated in the anterior hypothalamus, sitting just above and to the side of the optic chiasm in the brain of humans and other animals. The brain's sleep-promoting nuclei (e.g., the VLPO, parafacial zone, nucleus accumbens core, and lateral hypothalamic MCH neurons), together with the ascending arousal system which includes components in the brainstem, hypothalamus and basal forebrain, are the interconnected neural systems which control states of arousal, sleep, and transitions between these two states. The VLPO is active during sleep, particularly during non-rapid eye movement sleep (NREM sleep), and releases inhibitory neurotransmitters, mainly GABA and galanin, which inhibit neurons of the ascending arousal system that are involved in wakefulness and arousal. The VLPO is in turn innervated by neurons from several components of the ascending arousal system. The VLPO is activated by the endogenous sleep-promoting substances adenosine and prostaglandin D2. The VLPO is inhibited during wakefulness by the arousal-inducing neurotransmitters norepinephrine and acetylcholine. The role of the VLPO in sleep and wakefulness, and its association with sleep disorders – particularly insomnia and narcolepsy – is a growing area of neuroscience research. Structure At least 80% of neurons in the VLPO that project to the ascending arousal system are GA
https://en.wikipedia.org/wiki/National%20Biodiversity%20Conservation%20Area
A National Biodiversity Conservation Area (NBCA) is an environmentally protected area in Laos. There are all together 21 different NBCAs in Laos, protecting 29,775 square kilometers. Another 10 NBCAs have been proposed, many of them being treated by authorities as though they were already officially protected. List of NBCAs Corridor Nakai - Nam Theun and Phou Hin Poun National Biodiversity Conservation Area Dong Ampham National Biodiversity Conservation Area Dong Hua Sao National Protected Area Dong Phou Vieng National Protected Area Hin Nam No National Biodiversity Conservation Area Houei Nhang Conservation Area Khammouane Limestone National Biodiversity Conservation Area Nakai - Nam Theun National Biodiversity Conservation Area Nam Chuane Conservation Area Nam Et National Biodiversity Conservation Area Nam Ha National Protected Area Nam Kading National Protected Area Nam Kan Nam Phouy National Biodiversity Conservation Area Nam Theun Ext. National Biodiversity Conservation Area Nam Xam National Biodiversity Conservation Area Phou Den Din National Biodiversity Conservation Area Phou Kateup (Bolovens Northeast) Phou Kathong Phou Khao Khoay National Biodiversity Conservation Area Phou Louey National Biodiversity Conservation Area Phou Phanang National Biodiversity Conservation Area Phou Theung Phou Xang He National Protected Area Phou Xieng Thong National Protected Area Phu Luang (Boloven SW) Xe Bang Nouan National Biodiversity Conservati
https://en.wikipedia.org/wiki/Least%20mean%20squares%20filter
Least mean squares (LMS) algorithms are a class of adaptive filter used to mimic a desired filter by finding the filter coefficients that relate to producing the least mean square of the error signal (difference between the desired and the actual signal). It is a stochastic gradient descent method in that the filter is only adapted based on the error at the current time. It was invented in 1960 by Stanford University professor Bernard Widrow and his first Ph.D. student, Ted Hoff. Problem formulation The picture shows the various parts of the filter. is the input signal, which is then transformed by an unknown filter that we wish to match using . The output from the unknown filter is , which is then interfered with a noise signal , producing . Then the error signal is computed, and it is fed back to the adaptive filter, to adjust its parameters in order to minimize the mean square of the error signal . Relationship to the Wiener filter The realization of the causal Wiener filter looks a lot like the solution to the least squares estimate, except in the signal processing domain. The least squares solution for input matrix and output vector is The FIR least mean squares filter is related to the Wiener filter, but minimizing the error criterion of the former does not rely on cross-correlations or auto-correlations. Its solution converges to the Wiener filter solution. Most linear adaptive filtering problems can be formulated using the block diagram above. That is,
https://en.wikipedia.org/wiki/Recursive%20least%20squares%20filter
Recursive least squares (RLS) is an adaptive filter algorithm that recursively finds the coefficients that minimize a weighted linear least squares cost function relating to the input signals. This approach is in contrast to other algorithms such as the least mean squares (LMS) that aim to reduce the mean square error. In the derivation of the RLS, the input signals are considered deterministic, while for the LMS and similar algorithms they are considered stochastic. Compared to most of its competitors, the RLS exhibits extremely fast convergence. However, this benefit comes at the cost of high computational complexity. Motivation RLS was discovered by Gauss but lay unused or ignored until 1950 when Plackett rediscovered the original work of Gauss from 1821. In general, the RLS can be used to solve any problem that can be solved by adaptive filters. For example, suppose that a signal is transmitted over an echoey, noisy channel that causes it to be received as where represents additive noise. The intent of the RLS filter is to recover the desired signal by use of a -tap FIR filter, : where is the column vector containing the most recent samples of . The estimate of the recovered desired signal is The goal is to estimate the parameters of the filter , and at each time we refer to the current estimate as and the adapted least-squares estimate by . is also a column vector, as shown below, and the transpose, , is a row vector. The matrix product (which is the do
https://en.wikipedia.org/wiki/Aseptic%20meningitis
Aseptic meningitis is the inflammation of the meninges, a membrane covering the brain and spinal cord, in patients whose cerebral spinal fluid test result is negative with routine bacterial cultures. Aseptic meningitis is caused by viruses, mycobacteria, spirochetes, fungi, medications, and cancer malignancies. The testing for both meningitis and aseptic meningitis is mostly the same. A cerebrospinal fluid sample is taken by lumbar puncture and is tested for leukocyte levels to determine if there is an infection and goes on to further testing to see what the actual cause is. The symptoms are the same for both meningitis and aseptic meningitis but the severity of the symptoms and the treatment can depend on the certain cause. The most common cause of aseptic meningitis is by viral infection. Other causes may include side-effects from drugs and connective tissue disorders. Signs and symptoms Aseptic meningitis is a disease that can depend on the patient's age, however, research has shown some distinct symptoms that indicate the possibility of aseptic meningitis. A variety of patients notice a change in body temperatures (higher than normal temperatures 38-40 °C), marked with the possibility of vomiting, headaches, firm neck pain, and even lack of appetite. In younger patients, like babies, a meningeal inflammation can be noticed along with the possibility of hepatic necrosis and myocarditis. In serious cases, a multiple organ failure can also signal aseptic meningitis and
https://en.wikipedia.org/wiki/Glycal
Glycal is a name for cyclic enol ether derivatives of sugars having a double bond between carbon atoms 1 and 2 of the ring. The term "glycal" should not be used for an unsaturated sugar that has a double bond in any position other than between carbon atoms 1 and 2. History The first glycal was synthesized by Hermann Emil Fischer and Karl Zach in 1913. They synthesized this 1,2-unsaturated sugar from D-glucose and named their product D-glucal. Fischer believed he had synthesized an aldehyde, and therefore he gave the product a name that suggested this. By the time he discovered his mistake, the name "glycal" was adopted as a general name for all sugars with a double bond between carbon atoms 1 and 2. Conformation Glycals can be formed as pyranose (six-membered) or furanose (five-membered) rings, depending on the monosaccharide used as a starting material to synthesize the glycal. Glycals can also be classified as endo-glycals or exo-glycals. A glycal is an endo-glycal when the double bond is within the ring. If the hydroxyl group on carbon 1 has been replaced with another carbon atom, a double bond can also form outside the ring between carbon 1 and this new carbon. In this case, the product is called an exo-glycal. The glycal conformation that has been studied in most depth is that of the pyranose endo-glycal. The favoured conformation of this glycal is the half-chair, a result which has been confirmed by quantum mechanical calculations. Synthesis The original Fisch
https://en.wikipedia.org/wiki/The%20Street%20with%20No%20Name
The Street with No Name is a 1948 American film noir directed by William Keighley. A follow-up to The House on 92nd Street (1945), it tells the story of an undercover FBI agent, Gene Cordell (Mark Stevens), who infiltrates a deadly crime gang. Cordell's superior, FBI Inspector George A. Briggs (Lloyd Nolan), also appears in The House on 92nd Street. The film, shot in a semidocumentary style, takes place in the Skid Row section of fictional (actually Los Angeles) "Center City." Plot A crime wave, including a holdup at a nightclub that ends in a murder and a bank robbery in which a guard is killed, has hit Center City. A squad of FBI agents headed by inspector George A. Briggs meets with local FBI field officer Richard Atkins, police chief Bernard Harmatz and Police Commissioner Ralph Demory. After Briggs interrogates suspect Robert Danker, who claims he was not involved in either killing and that he has been framed, various tests are run at the FBI laboratory in Washington that exonerate Danker. Later Danker, who has been bailed out by "John Smith," is found stabbed to death. At the FBI Academy in Quantico, Virginia, Briggs briefs agent Gene Cordell, who is going undercover in Center City to try to infiltrate the gang Briggs thinks is responsible for all three killings. Cordell takes a bus into Center City and rents a room at the same "Skid Row" hotel in which Danker had been living. Fellow agent Cy Gordon is in a similar hotel across the street from him. Using the name Georg
https://en.wikipedia.org/wiki/Amacrine%20cell
Amacrine cells are interneurons in the retina. They are named from the Greek roots a– ("non"), makr– ("long") and in– ("fiber"), because of their short neuronal processes. Amacrine cells are inhibitory neurons, and they project their dendritic arbors onto the inner plexiform layer (IPL), they interact with retinal ganglion cells, and bipolar cells or both of these. Structure Amacrine cells operate at inner plexiform layer (IPL), the second synaptic retinal layer where bipolar cells and retinal ganglion cells form synapses. There are at least 33 different subtypes of amacrine cells based just on their dendrite morphology and stratification. Like horizontal cells, amacrine cells work laterally, but whereas horizontal cells are connected to the output of rod and cone cells, amacrine cells affect the output from bipolar cells, and are often more specialized. Each type of amacrine cell releases one or several neurotransmitters where it connects with other cells. They are often classified by the width of their field of connection, which layer(s) of the stratum in the IPL they are in, and by neurotransmitter type. Most are inhibitory using either gamma-Aminobutyric acid or glycine as neurotransmitters. Types As mentioned above, there are several different ways to divide the many different types of amacrine cells into subtypes. GABAergic, glycinergic, or neither: Amacrine cells can be either GABAergic, glycinergic or neither depending on what inhibitory neurotransmitter they ex
https://en.wikipedia.org/wiki/Retina%20horizontal%20cell
Horizontal cells are the laterally interconnecting neurons having cell bodies in the inner nuclear layer of the retina of vertebrate eyes. They help integrate and regulate the input from multiple photoreceptor cells. Among their functions, horizontal cells are believed to be responsible for increasing contrast via lateral inhibition and adapting both to bright and dim light conditions. Horizontal cells provide inhibitory feedback to rod and cone photoreceptors. They are thought to be important for the antagonistic center-surround property of the receptive fields of many types of retinal ganglion cells. Other retinal neurons include photoreceptor cells, bipolar cells, amacrine cells, and retinal ganglion cells. Structure Depending on the species, there are typically one or two classes of horizontal cells, with a third type sometimes proposed. Horizontal cells span across photoreceptors and summate inputs before synapsing onto photoreceptor cells. Horizontal cells may also synapse onto bipolar cells, but this remains uncertain. There is a greater density of horizontal cells towards the central region of the retina. In the cat, it is observed that A-type horizontal cells have a density of 225 cells/mm2 near the center of the retina and a density of 120 cells/mm2 in more peripheral retina. Horizontal cells and other retinal interneuron cells are less likely to be near neighbours of the same subtype than would occur by chance, resulting in ‘exclusion zones’ that separate t
https://en.wikipedia.org/wiki/APX
In computational complexity theory, the class APX (an abbreviation of "approximable") is the set of NP optimization problems that allow polynomial-time approximation algorithms with approximation ratio bounded by a constant (or constant-factor approximation algorithms for short). In simple terms, problems in this class have efficient algorithms that can find an answer within some fixed multiplicative factor of the optimal answer. An approximation algorithm is called an -approximation algorithm for input size if it can be proven that the solution that the algorithm finds is at most a multiplicative factor of times worse than the optimal solution. Here, is called the approximation ratio. Problems in APX are those with algorithms for which the approximation ratio is a constant . The approximation ratio is conventionally stated greater than 1. In the case of minimization problems, is the found solution's score divided by the optimum solution's score, while for maximization problems the reverse is the case. For maximization problems, where an inferior solution has a smaller score, is sometimes stated as less than 1; in such cases, the reciprocal of is the ratio of the score of the found solution to the score of the optimum solution. A problem is said to have a polynomial-time approximation scheme (PTAS) if for every multiplicative factor of the optimum worse than 1 there is a polynomial-time algorithm to solve the problem to within that factor. Unless P = NP there exist p
https://en.wikipedia.org/wiki/KIR
KIR, Kir or kir may refer to: Biology Inward-rectifier potassium channel Kir Killer-cell immunoglobulin-like receptor, a receptor protein expressed on the surface of natural killer cells and some T-cells Bodies of water Kir (river), in northern Albania Kir Lake, near Dijon, France People Kir Fard, Armenian nobleman of the 12th–13th centuries Kir Nesis (1934–2003), Russian biologist Kir Bulychev, Russian writer Félix Kir (1876–1968), priest in the French Resistance Kir, a character in Detective Conan Places Republic of Kiribati in the central Pacific (ISO code: KIR) Kir of Moab, biblical stronghold Land of Kir, biblical location Transport Katihar Junction railway station, Bihar; station code KIR Kerry Airport, Ireland (IATA code: KIR) Kirkby railway station, Merseyside, England; National Rail station code KIR Other Kir (cocktail), alcoholic beverage Kyrgyz language (ISO code: kir) Krajowa Izba Rozliczeniowa, an automated clearing house in Poland See also Kirs (disambiguation) Kyr
https://en.wikipedia.org/wiki/SWiSH%20Max
SWiSH Max is a Flash, Dynamic HTML and vector graphic creation tool that is commonly used to create interactive and cross-platform movies, animations, and presentations. It was developed and distributed by Swishzone.com Pty Ltd, based in Sydney, Australia. In October 2016, Swishzone.com posted a message on their website indicating that Swishzone.com was closed and their products were removed from distribution. A software key generated was made available for download from their home page. SWiSH Max primarily outputs to the .swf format, which is currently under control of Adobe Systems. SWiSH Max was designed for the Windows operating system. SWiSH Max3 added features such as a knife drawing tool, advanced shape operations, and ActionScript 2.0 classes. Graphics SWiSH Max is generally considered to be a simpler and less costly Flash creation tool in comparison with Adobe Flash. SWiSH Max does not support some Adobe Flash features such as ActionScript 3.0, shape tweens, and bitmap drawing capabilities. It does, however, include general Flash creation features such as vector drawing, motion tweens, and symbol editing. In addition, SWiSH Max incorporates a number of automated effects and transitions, which make building certain Flash elements such as buttons, advanced transition effects, and interactive Flash sites simpler. One drawback of SWiSH Max is its inability to open or save .fla files, which limits exchanges between other programs to final .swf files. Scripting The scr
https://en.wikipedia.org/wiki/Vapor%20pressures%20of%20the%20elements%20%28data%20page%29
Vapor pressure Notes Values are given in terms of temperature necessary to reach the specified pressure. Valid results within the quoted ranges from most equations are included in the table for comparison. A conversion factor is included into the original first coefficients of the equations to provide the pressure in pascals (CR2: 5.006, SMI: -0.875). Ref. SMI uses temperature scale ITS-48. No conversion was done, which should be of little consequence however. The temperature at standard pressure should be equal to the normal boiling point, but due to the considerable spread does not necessarily have to match values reported elsewhere. log refers to log base 10 (T/K) refers to temperature in Kelvin (K) (P/Pa) refers to pressure in Pascal (Pa) References CRC.a-m David R. Lide (ed), CRC Handbook of Chemistry and Physics, 84th Edition. CRC Press. Boca Raton, Florida, 2003; Section 6, Fluid Properties; Vapor Pressure Uncertainties of several degrees should generally be assumed. (e) Indicates extrapolated values beyond the region of experimental data, subject to greater uncertainty. (i) Indicates values calculated from ideal gas thermodynamic functions. (s) Indicates the substance is solid at this temperature. As quoted from these sources: a - Lide, D.R., and Kehiaian, H.V., CRC Handbook of Thermophysical and Thermochemical Data, CRC Press, Boca Raton, Florida, 1994. b - Stull, D., in American Institute of Physics Handbook, Third Edition, Gray, D.E., Ed., McGraw Hill, New Yo
https://en.wikipedia.org/wiki/Frequency%20grid
For telecommunications, a frequency grid is a table of all the central frequencies (and corresponding wavelengths) of channels allowed in a communications system. The most common frequency grid used for fiber-optic communication is that used for channel spacing in Dense Wavelength Division Multiplexing (DWDM) at wavelengths around 1550 nm and defined by ITU-T G.694.1. The grid is defined relative to 193.1 THz and extends from 191.7 THz to 196.1 THz with 100 GHz spacing. While defined in frequency, the grid is often expressed in terms of wavelength, in which case it covers the wavelength range of 1528.77 nm to 1563.86 nm with approximately a 0.8 nm channel spacing. For practical purposes, the grid has been extended to cover 186 THz to 201 THz and subdivided to provide 50 GHz and 25 GHz spaced grids. References External links Complete ITU grid table for 100 Ghz spacing International Standardization Activities on Optical Interfaces Multiplexing ITU-T recommendations ITU-T G Series Recommendations
https://en.wikipedia.org/wiki/Pulmonary%20surfactant
Pulmonary surfactant is a surface-active complex of phospholipids and proteins formed by type II alveolar cells. The proteins and lipids that make up the surfactant have both hydrophilic and hydrophobic regions. By adsorbing to the air-water interface of alveoli, with hydrophilic head groups in the water and the hydrophobic tails facing towards the air, the main lipid component of surfactant, dipalmitoylphosphatidylcholine (DPPC), reduces surface tension. As a medication, pulmonary surfactant is on the WHO Model List of Essential Medicines, the most important medications needed in a basic health system. Function To increase pulmonary compliance. To prevent atelectasis (collapse of the alveoli or atriums) at the end of expiration. To facilitate recruitment of collapsed airways. Alveoli can be compared to gas in water, as the alveoli are wet and surround a central air space. The surface tension acts at the air-water interface and tends to make the bubble smaller (by decreasing the surface area of the interface). The gas pressure (P) needed to keep an equilibrium between the collapsing force of surface tension (γ) and the expanding force of gas in an alveolus of radius r is expressed by the Young–Laplace equation: Compliance Compliance is the ability of lungs and thorax to expand. Lung compliance is defined as the volume change per unit of pressure change across the lung. Measurements of lung volume obtained during the controlled inflation/deflation of a normal lung sh
https://en.wikipedia.org/wiki/G%20protein-gated%20ion%20channel
G protein-gated ion channels are a family of transmembrane ion channels in neurons and atrial myocytes that are directly gated by G proteins. Overview of mechanisms and function Generally, G protein-gated ion channels are specific ion channels located in the plasma membrane of cells that are directly activated by a family of associated proteins. Ion channels allow for the selective movement of certain ions across the plasma membrane in cells. More specifically, in nerve cells, along with ion transporters, they are responsible for maintaining the electrochemical gradient across the cell. G proteins are a family of intracellular proteins capable of mediating signal transduction pathways. Each G protein is a heterotrimer of three subunits: α-, β-, and γ- subunits. The α-subunit (Gα) typically binds the G protein to a transmembrane receptor protein known as a G protein-coupled receptor, or GPCR. This receptor protein has a large, extracellular binding domain which will bind its respective ligands (e.g. neurotransmitters and hormones). Once the ligand is bound to its receptor, a conformational change occurs. This conformational change in the G protein allows Gα to bind GTP. This leads to yet another conformational change in the G protein, resulting in the separation of the βγ-complex (Gβγ) from Gα. At this point, both Gα and Gβγ are active and able to continue the signal transduction pathway. Different classes of G protein-coupled receptors have many known functions i
https://en.wikipedia.org/wiki/Tin%28II%29%20chloride
Tin(II) chloride, also known as stannous chloride, is a white crystalline solid with the formula . It forms a stable dihydrate, but aqueous solutions tend to undergo hydrolysis, particularly if hot. SnCl2 is widely used as a reducing agent (in acid solution), and in electrolytic baths for tin-plating. Tin(II) chloride should not be confused with the other chloride of tin; tin(IV) chloride or stannic chloride (SnCl4). Chemical structure SnCl2 has a lone pair of electrons, such that the molecule in the gas phase is bent. In the solid state, crystalline SnCl2 forms chains linked via chloride bridges as shown. The dihydrate has three coordinates as well, with one water on the tin and another water on the first. The main part of the molecule stacks into double layers in the crystal lattice, with the "second" water sandwiched between the layers. Chemical properties Tin(II) chloride can dissolve in less than its own mass of water without apparent decomposition, but as the solution is diluted, hydrolysis occurs to form an insoluble basic salt: SnCl2 (aq) + H2O (l) Sn(OH)Cl (s) + HCl (aq) Therefore, if clear solutions of tin(II) chloride are to be used, it must be dissolved in hydrochloric acid (typically of the same or greater molarity as the stannous chloride) to maintain the equilibrium towards the left-hand side (using Le Chatelier's principle). Solutions of SnCl2 are also unstable towards oxidation by the air: 6 SnCl2 (aq) + O2 (g) + 2 H2O (l) → 2 SnCl4 (aq) + 4 Sn(OH)Cl (s)
https://en.wikipedia.org/wiki/Crystallophone
A crystallophone is a musical instrument that produces sound from glass. One of the best known crystallophones is the glass harmonica, a set of rotating glass bowls which produce eerie, clear tones when rubbed with a wet finger. Musical glasses, the glass harp, were documented in Persia in the 14th century. The "ethereal" quality of instruments such as the glass harmonica exemplified the and for a while, "the instrument was extraordinarily popular...[but] About 1830 the instrument fell into oblivion." The glasschord (or glasscord) resembles the celesta (a struck plaque idiophone operated by a keyboard) but uses keyboard-driven hammers to strike glass bars instead of metal bars. The glass marimba is similar to the marimba (a stick percussion instrument with a keyboard layout), but has bars of glass instead of wood. The bars, which the performer strikes with padded sticks, are perched on a glass box to provide the necessary resonance. A rare Thai instrument called (; literally "glass xylophone") has been used by the Thai music ensemble Fong Naam; it appears on their 1992 CD The Sleeping Angel: Thai Classical Music. In popular culture In Lydia Syson's biography, Doctor of Love: James Graham and his Celestial Bed, sexologist James Graham uses the glass harmonica for musical therapy purposes. Benjamin Franklin was inspired to create his glass harmonica in 1763 after attending a recital performed on musical glasses in London in 1761. See also Lithophone Verrophone Refer
https://en.wikipedia.org/wiki/Bortezomib
Bortezomib, sold under the brand name Velcade among others, is an anti-cancer medication used to treat multiple myeloma and mantle cell lymphoma. This includes multiple myeloma in those who have and have not previously received treatment. It is generally used together with other medications. It is given by injection. Common side effects include nausea, diarrhea, tiredness, low platelets, fever, numbness, low white blood cells, shortness of breath, rash and abdominal pain. Other severe side effects include low blood pressure, tumour lysis syndrome, heart failure, and reversible posterior leukoencephalopathy syndrome. It is in the class of medications known as proteasome inhibitor. It works by inhibiting proteasomes, cellular complexes that break down proteins. Bortezomib was approved for medical use in the United States in 2003 and in the European Union in 2004. It is on the World Health Organization's List of Essential Medicines. It is available as a generic medication. Medical use Two open-label trials established the efficacy of bortezomib (with or without dexamethasone) on days 1,4,8, and 11 of a 21-day cycle for a maximum of eight cycles in heavily pretreated people with relapsed/refractory multiple myeloma. The phase III demonstrated the superiority of bortezomib over a high-dose dexamethasone regimen (e.g. median TTP 6.2 vs 3.5 months, and 1-year survival 80% vs 66%). New studies show that bortezomib may potentially help recover from vincristine treatment in treating
https://en.wikipedia.org/wiki/Glasschord
The glasschord (French: fortepiano à cordes de verre) is a struck crystallophone resembling the celesta, invented circa 1785 by physicist M. Beyer of Paris. It creates sound by using cloth covered wooden hammers to strike glass tubes laid on a cloth strip, with no dampeners. The instrument has a range of three octaves, in various models from c' to c'', f' to f'', and g' to g''. The instrument was largely inspired by the glass harmonica created by Benjamin Franklin, and was given the name glasschord by him. On 6 July 1785, Thomas Jefferson that Franklin carried a version of the instrument with him, describing it as a sticcado. Beyer originally presented the instrument on 19 January 1785, in a presentation at the French Academy of Sciences, while the instrument still was nameless, with the instrument being publicised in the Journal de Paris multiple times through the same year. Many glasschords were built by Chappell & Co., until around 1815. The instrument was used in some scores, most notable by Hector Berlioz, who wrote the first version of La Tempête, and Camille Saint-Saëns who used the instrument in L'aquarium. References Keyboard instruments Crystallophones Stick percussion idiophones
https://en.wikipedia.org/wiki/Likely
Likely may refer to: Probability Likelihood function Likely (surname) Likely, British Columbia, Canada, a community Likely, California, United States, a census-designated place Likely McBrien (1892-1956), leading Australian rules football administrator in the Victorian Football League In the nomenclature of political forecasting, a "likely" seat is one that is predicted, but not definitively, to probably be won by a particular political party See also Likely Airport (disambiguation)
https://en.wikipedia.org/wiki/Tight%20junction
Tight junctions, also known as occluding junctions or zonulae occludentes (singular, zonula occludens), are multiprotein junctional complexes whose canonical function is to prevent leakage of solutes and water and seals between the epithelial cells. They also play a critical role maintaining the structure and permeability of endothelial cells. Tight junctions may also serve as leaky pathways by forming selective channels for small cations, anions, or water. The corresponding junctions that occur in invertebrates are septate junctions. Structure Tight junctions are composed of a branching network of sealing strands, each strand acting independently from the others. Therefore, the efficiency of the junction in preventing ion passage increases exponentially with the number of strands. Each strand is formed from a row of transmembrane proteins embedded in both plasma membranes, with extracellular domains joining one another directly. There are at least 40 different proteins composing the tight junctions. These proteins consist of both transmembrane and cytoplasmic proteins. The three major transmembrane proteins are occludin, claudins, and junction adhesion molecule (JAM) proteins. These associate with different peripheral membrane proteins such as ZO-1 located on the intracellular side of plasma membrane, which anchor the strands to the actin component of the cytoskeleton. Thus, tight junctions join together the cytoskeletons of adjacent cells. Transmembrane proteins: Occ
https://en.wikipedia.org/wiki/Kremersite
Kremersite is a rare mineral which is a hydrated multiple chloride of iron, ammonium and potassium with the formula: (NH4,K)2FeCl5·H2O. Kremersite is a brown-red to orange mineral that crystallizes in the orthorhombic system. It is a water-soluble mineral that is found around volcanic fumaroles. Occurs at Vesuvius, Italy and Mount Etna, Sicily. It was discovered in 1853 and named for the German chemist, Peter Kremers (born 1827). References Mindat Webmineral Potassium minerals Halide minerals Iron(III) minerals Orthorhombic minerals Minerals in space group 62
https://en.wikipedia.org/wiki/Polybrominated%20biphenyl
Polybrominated biphenyls (PBBs), also called brominated biphenyls or polybromobiphenyls, are a group of manufactured chemicals that consist of polyhalogenated derivatives of a biphenyl core. Their chlorine analogs are the PCBs. While once widely used commercially, PBBs are now controlled substances under the Restriction of Hazardous Substances Directive, which limits their use in electrical and electronic products sold in the EU. Characteristics PBBs usually exist as colorless to off-white solids. PBBs soften at 72 degrees Celsius and decompose above 300 degrees Celsius. They have low vapor pressure, are very soluble in benzene and toluene, and insoluble in water. They are degraded by UV light. Application PBBs are used as flame retardants of the brominated flame retardant group. They are added to plastics used in products such as home electrical appliances, textiles, plastic foams, laptop cabinets, etc. to make them difficult to burn. A number of substituted PBBs found application in medicine, namely bromophene and bromofenofos. Health hazards Exposure to the coplanar stereoisomer 3,3',4,4',5,5'-hexabromobiphenyl (but not the non-coplanar stereoisomer) in genetically susceptible mice is known to cause immunotoxicity and disorders related to the central nervous system, and even at doses as low as 2.5 mg/kg, excess neonatal fatalities are observed (LD50 is from 5–10 mg/kg). The mechanism of toxicity is cellular oxidative stress by aryl hydrocarbon receptor activation.
https://en.wikipedia.org/wiki/Bernard%20Koopman
Bernard Osgood Koopman (January 19, 1900 – August 18, 1981) was a French-born American mathematician, known for his work in ergodic theory, the foundations of probability, statistical theory and operations research. Education and work After living in France and Italy, Koopman emigrated to the United States in 1915. Koopman was a student of George David Birkhoff and his initial work concentrated on dynamical systems and mathematical physics. In 1931/1932, Koopman and John von Neumann proposed a Hilbert space formulation of classical mechanics, known as the Koopman–von Neumann classical mechanics. During World War II, he joined the Anti-Submarine Warfare Operations Research Group (ASWORG, later ORG) in Washington, D.C., directed by Philip M. Morse, to work for the U.S. Navy. The work of Koopman and his colleagues at ASWORG concerned the development of techniques for the US Navy to hunt U-boats. The theoretical work laid the foundations for search theory which subsequently became a field of its own within operations research. Their results remained classified Confidential for many years after the war; after 1955 Koopman set out to publish three articles on easily declassifiable portions of the work in the Journal of the Operations Research Society of America. He wrote down the results in detailed form in the book Search and Screening which was declassified in 1958. A large part of his work is a systematization of the work performed by his group at ASWORG; the portions on opt
https://en.wikipedia.org/wiki/Crystal%20Hunt
Crystal Clarese Hunt (born February 5, 1985) is an American actress and producer. She is known for playing Lizzie Spaulding on the CBS soap opera Guiding Light (2003–06) and Stacy Morasco on the ABC soap opera One Life to Live (2009–10, 2012). Life and career Hunt was born in Clearwater, Florida. She started her career as a child performer, notable appearing the film Problem Child 2 (1991). Hunt has starred in many commercials, including one for The Walt Disney Company's 25th anniversary celebration and an anti-drug advertisement with *NSYNC. In 2003, she was cast as Lizzie Spaulding, the troubled daughter of the long-suffering couple Philip and Beth Raines, on the CBS soap opera Guiding Light, which she played from 2003 to 2006. She received a Daytime Emmy Award nomination in 2005 for Outstanding Younger Actress in a Drama Series for the role. Hunt appeared in the 2005 film The Derby Stallion, and appeared in the 2007 Universal Pictures film Sydney White as Demetria "Dinky" Rosemead Hodgekiss. She joined ABC soap opera One Life to Live in February 2009, playing Stacy Morasco. She left the show on February 16, 2010. She returned to the show as the ghostly Stacy in March 2010, and in Clint Buchanan's vision of Hell in January 2012. Hunt starred in the 2015 reality series Queens of Drama, and later in the Pureflix soap opera, Hilton Head Island. In 2019, she starred, created and produced web-series Mood Swings. Filmography Film Television References External links Cryst
https://en.wikipedia.org/wiki/Nanodomain
A nanodomain is a nanometer-sized cluster of proteins found in a cell membrane. They are associated with the signal which occurs when a single calcium ion channel opens on a cell membrane, allowing an influx of calcium ions (Ca) which extend in a plume a few tens of nanometres from the channel pore. In a nanodomain, the coupling distance, that is, the distance between the calcium-binding proteins which sense the calcium, and the calcium channel, is very small, less than , which allows rapid signalling. The formation of a nanodomain signal is virtually instantaneous following the opening of the calcium channel, as calcium ions move rapidly into the cell along a steep concentration gradient. The nanodomain signal collapses just as quickly when the calcium channel closes, as the ions rapidly diffuse away from the pore. Formation of a nanodomain signal requires the influx of only approximately 1000 calcium ions. Coupling distances greater than , mediated by a larger number of channels, are referred to as microdomains. nanodomain Properties Nanodomain signals are thought to improve the temporal precision of fast exocytosis of vesicles due to two specific properties: The peak concentration of calcium ions will be reached incredibly quick (within a microsecond) and maintained as long as the channel is open. Closure of the channel leads to a rapid collapse of the domain due to lateral diffusion away from the pore (the site of entry). The lateral diffusion of microdomains additi
https://en.wikipedia.org/wiki/Lexical%20diffusion
Lexical diffusion is the hypothesis that a sound change is an abrupt change that spreads gradually across the words in a language to which it is applicable. It contrasts with the Neogrammarian view that a sound change results from phonetically-conditioned articulatory drift acting uniformly on all applicable words, which implies that sound changes are regular, with exceptions attributed to analogy and dialect borrowing. Similar views were expressed by Romance dialectologists in the late 19th century but were reformulated and renamed by William Wang and coworkers studying varieties of Chinese in the 1960s and the 1970s. William Labov found evidence for both processes but argued that they operate at different levels. Neogrammarians A key assumption of historical linguistics is that sound change is regular. The principle was summarized by the Neogrammarians in the late 19th century in the slogan "sound laws suffer no exceptions" and forms the basis of the comparative method of reconstruction and the tree model of linguistic evolution. Inspired by the Uniformitarian Principle of geology, Neogrammarians such as Hermann Paul described regularity as a consequence of the operation of sound change as an imperceptible articulatory drift conditioned by the phonetic environment. Leonard Bloomfield later summarized this view: He summarized the mechanism as "phonemes change". Despite the unequivocal form in which these slogans are often quoted, the Neogrammarians admitted two exceptio
https://en.wikipedia.org/wiki/British%20Rail%20Class%2043%20%28HST%29
The British Rail Class 43 (HST) is the TOPS classification used for the InterCity 125 High Speed Train (formerly Classes 253 and 254) diesel-electric power cars, built by British Rail Engineering Limited from 1975 to 1982, and in service in the UK since 1976. The class is officially the fastest diesel locomotive in the world, with an absolute maximum speed of , and a regular service speed of . The record run was led by 43102 (43302) and trailed by 43159. History and background In the early 1970s, the British Railways Board made the decision to replace its main-line express diesel traction. Financial limitations were tight, so mass electrification was not possible. As a result, a new generation of high-speed diesel trains had to be developed. Experience with the high-speed Class 55 Deltic locomotives had shown that a low axle weight was essential to avoid damage to the track at sustained high speed, and that high-speed engines were the only way to provide a good enough power-to-weight ratio for diesels. To power the HST at up to , each power car had a new diesel engine, the 12-cylinder Paxman Valenta, running at 1,500rpm and developing . The 70-tonne weight of the power car gave it a 17.5-tonne axle loading. Development and design Prototype The prototype set was developed at the Railway Technical Centre, Derby, the power cars having been constructed by British Rail Engineering Limited's (BREL) Crewe Works and the British Rail Mark 3 passenger cars by BREL's Derby Litchur
https://en.wikipedia.org/wiki/British%20Rail%20Class%2043%20%28Warship%20Class%29
The British Rail Class 43 diesel-hydraulic locomotives were built by the North British Locomotive Company (NBL) from 1960 to 1962. They were numbered D833–D865. Classification The D800 series diesel-hydraulic 'Warship Class', of B-B wheel arrangement, was constructed by two different builders. Those locomotives built by British Railways at Swindon Works were originally numbered D800-D832 and D866-D870. They were allocated Class 42 under the 1968 classification system, while those built by the North British Locomotive Company (NBL) were originally numbered D833-D865 and allocated Class 43. Because of their early withdrawal dates, neither the Swindon- nor the NBL-built locomotives carried TOPS numbers. More detail on factors common to both types can be found in the article on the Swindon-built British Rail Class 42. Mechanical details The NBL-built D800s differed mechanically from the Swindon-built batch: the Swindon locomotives used Maybach engines connected to Mekydro hydraulic transmissions whereas the NBL-built examples used MAN engines and Voith transmissions. NBL had entered into an arrangement with the German company MAN AG in the early 1950s to market MAN's engine designs in the UK: NBL was anxious to enter the diesel locomotive market, especially once it became apparent that British Railways would be seeking large quantities of such locomotives when the "Modernisation Plan" was announced. MAN were equally keen to obtain a slice of the UK market for themselves.
https://en.wikipedia.org/wiki/Alloxan
Alloxan, sometimes referred to as alloxan hydrate, is the name of the organic compound with the formula OC(N(H)CO)2C(OH)2. It is classified as a derivative of pyrimidine. The anhydrous derivative OC(N(H)CO)2CO is also known, as well as a dimeric derivative. These are some of the earliest known organic compounds. They exhibit a variety of biological activities. History and literature The compound was discovered by Justus von Liebig and Friedrich Wöhler. It is one of the oldest named organic compounds. It was originally prepared in 1818 by Luigi Valentino Brugnatelli (1761-1818) and was named in 1838 by Wöhler and Liebig. The name "Alloxan" emerged from an amalgamation of the words "allantoin" and "Oxalsäure" (oxalic acid). The alloxan model of diabetes was first described in rabbits by Dunn, Sheehan and McLetchie in 1943. The name is derived from allantoin, a product of uric acid excreted by the fetus into the allantois, and oxaluric acid derived from oxalic acid and urea, found in urine. Alloxan was used in the production of the purple dye murexide, discovered by Carl Wilhelm Scheele in 1776. Murexide is the product of the complex in-situ multistep reaction of alloxantin and gaseous ammonia. Murexide results from the condensation of the unisolated intermediate uramil with alloxan, liberated during the course of the reaction. Scheele sourced uric acid from human calculi (such as kidney stones) and called the compound lithic acid. William Prout investigated the compoun
https://en.wikipedia.org/wiki/Keikogi
(, "practice", , "dress or "clothes"), also known as or , is a traditional uniform worn for training in Japanese martial arts and their derivatives. Emerging in the late 19th century, the was developed by judo founder Kanō Jigorō. Origin Japanese martial arts historian Dave Lowry speculates that Kanō derived the uniform's design from the uniforms of Japanese firefighters' heavy hemp jackets, . By 1920, the as it exists today was worn by Kanō's students for judo practice; a photo displayed in the Kodokan (judo headquarters) taken in 1920 shows Kanō himself wearing a modern . Until the 1920s, Okinawan karate practice was usually performed in everyday clothes. Given the social climate between the Japanese and Okinawans during this time, karate was seen as brutish compared to Japanese martial arts, which had their roots in samurai culture, such as jujutsu. To help market karate to the Japanese, Gichin Funakoshi – the founder of Shotokan karate and the instructor responsible for importing karate to mainland Japan – adopted a uniform style similar to Kanō's design. Construction Over time, karate practitioners modified the for karate by lightening the weave of the fabric, and adding strings to the inside of the jacket, tied to keep the jacket closed. The jacket is also held closed by a belt or . The top part of the is called the . The trousers of the are called , or . In modern times, white, black, blue and indigo are the most common colours of . In competitive judo, one
https://en.wikipedia.org/wiki/Entropic%20force
In physics, an entropic force acting in a system is an emergent phenomenon resulting from the entire system's statistical tendency to increase its entropy, rather than from a particular underlying force on the atomic scale. Mathematical formulation In the canonical ensemble, the entropic force associated to a macrostate partition is given by where is the temperature, is the entropy associated to the macrostate , and is the present macrostate. Examples Pressure of an ideal gas The internal energy of an ideal gas depends only on its temperature, and not on the volume of its containing box, so it is not an energy effect that tends to increase the volume of the box as gas pressure does. This implies that the pressure of an ideal gas has an entropic origin. What is the origin of such an entropic force? The most general answer is that the effect of thermal fluctuations tends to bring a thermodynamic system toward a macroscopic state that corresponds to a maximum in the number of microscopic states (or micro-states) that are compatible with this macroscopic state. In other words, thermal fluctuations tend to bring a system toward its macroscopic state of maximum entropy. Brownian motion The entropic approach to Brownian movement was initially proposed by R. M. Neumann. Neumann derived the entropic force for a particle undergoing three-dimensional Brownian motion using the Boltzmann equation, denoting this force as a diffusional driving force or radial force. In
https://en.wikipedia.org/wiki/Shell%20theorem
In classical mechanics, the shell theorem gives gravitational simplifications that can be applied to objects inside or outside a spherically symmetrical body. This theorem has particular application to astronomy. Isaac Newton proved the shell theorem and stated that: A spherically symmetric body affects external objects gravitationally as though all of its mass were concentrated at a point at its center. If the body is a spherically symmetric shell (i.e., a hollow ball), no net gravitational force is exerted by the shell on any object inside, regardless of the object's location within the shell. A corollary is that inside a solid sphere of constant density, the gravitational force within the object varies linearly with distance from the center, becoming zero by symmetry at the center of mass. This can be seen as follows: take a point within such a sphere, at a distance from the center of the sphere. Then you can ignore all of the shells of greater radius, according to the shell theorem (2). But the point can be considered to be external to the remaining sphere of radius r, and according to (1) all of the mass of this sphere can be considered to be concentrated at its centre. The remaining mass is proportional to (because it is based on volume). The gravitational force exerted on a body at radius r will be proportional to (the inverse square law), so the overall gravitational effect is proportional to so is linear in These results were important to Newton's analysis
https://en.wikipedia.org/wiki/Hyperbolic%20secant%20distribution
In probability theory and statistics, the hyperbolic secant distribution is a continuous probability distribution whose probability density function and characteristic function are proportional to the hyperbolic secant function. The hyperbolic secant function is equivalent to the reciprocal hyperbolic cosine, and thus this distribution is also called the inverse-cosh distribution. Generalisation of the distribution gives rise to the Meixner distribution, also known as the Natural Exponential Family - Generalised Hyperbolic Secant or NEF-GHS distribution. Definitions Probability density function A random variable follows a hyperbolic secant distribution if its probability density function can be related to the following standard form of density function by a location and shift transformation: where "sech" denotes the hyperbolic secant function. Cumulative distribution function The cumulative distribution function (cdf) of the standard distribution is a scaled and shifted version of the Gudermannian function, where "arctan" is the inverse (circular) tangent function. Johnson et al. (1995) places this distribution in the context of a class of generalized forms of the logistic distribution, but use a different parameterisation of the standard distribution compared to that here. Ding (2014) shows three occurrences of the Hyperbolic secant distribution in statistical modeling and inference. Properties The hyperbolic secant distribution shares many properties with the
https://en.wikipedia.org/wiki/Incoherent%20scatter
Incoherent scattering is a type of scattering phenomenon in physics. The term is most commonly used when referring to the scattering of an electromagnetic wave (usually light or radio frequency) by random fluctuations in a gas of particles (most often electrons). The most well known practical application is known as incoherent scatter radar theory, a ground-based technique for studying the Earth's ionosphere first proposed by Professor William E. Gordon in 1958. A radar beam scattering off electrons in the ionospheric plasma creates an incoherent scatter return. When an electromagnetic wave is transmitted through the atmosphere, each of the electrons in the ionospheric plasma essentially acts as an antenna excited by the incoming wave, and the wave is re-radiated from the electron. Since the electrons are all moving at varying speeds as a result of ionospheric dynamics and random thermal motion, the reflection from each electron is also Doppler shifted. The receiver on the ground then receives a signal composed of the superposition of the re-radiated waves from all the electrons in the path of the incoming wave. Since the positively-charged ions also present in the ionosphere are orders of magnitude more massive, they are not as readily excited by the incoming electromagnetic wave in the way that the electrons are, so they do not re-radiate the signal. However, the electrons tend to remain close to the positively-charged ions. As a result, the distribution function of t
https://en.wikipedia.org/wiki/Stentz
Stentz may refer to: Zack Stentz, one of the scriptwriters of 2003 film Agent Cody Banks Stentz is an official codename for Fedora Core release 4 Stentz's Algorithm German-language surnames
https://en.wikipedia.org/wiki/Fas%20ligand
Fas ligand (FasL or CD95L or CD178) is a type-II transmembrane protein expressed on cytotoxic T lymphocytes and natural killer (NK) cells. Its binding with Fas receptor (FasR) induces programmed cell death in the FasR-carrying target cell. Fas ligand/receptor interactions play an important role in the regulation of the immune system and the progression of cancer. Structure Fas ligand or FasL is a homotrimeric type II transmembrane protein that belongs to the tumor necrosis factor (TNF) family. It signals through trimerization of FasR, which spans the membrane of the target cell. This trimerization usually leads to apoptosis, or programmed cell death. Soluble Fas ligand is generated by cleaving membrane-bound FasL at a conserved cleavage site by the external matrix metalloproteinase MMP-7. Receptors FasR: The Fas receptor (FasR), or CD95, is the most intensely studied member of the death receptor family. The gene is situated on chromosome 10 in humans and 19 in mice. Previous reports have identified as many as eight splice variants, which are translated into seven isoforms of the protein. Many of these isoforms are rare haplotypes that are usually associated with a state of disease. Apoptosis-inducing Fas receptor is dubbed isoform 1 and is a type 1 transmembrane protein. It consists of three cysteine-rich pseudorepeats, a transmembrane domain, and an intracellular death domain. DcR3: Decoy receptor 3 (DcR3) is a recently discovered decoy receptor of the tumor necrosis
https://en.wikipedia.org/wiki/List%20of%20films%20set%20in%20Houston
Part or all of these movies/shows either take place, or are set, in Houston, Texas or the surrounding area: The Houston Story (1956) - starring Gene Barry and Barbara Hale (of Perry Mason) Hellfighters (1968) - with John Wayne Brewster McCloud (1970) – first film to be filmed inside the Astrodome The Getaway (1972) – filmed in Huntsville, Texas The Thief Who Came to Dinner (1973) – set and filmed in Houston Sugar Hill (1974) - set and filmed in Houston Together Brothers (1974) - filmed in Galveston, Texas Rollerball (1975) – set in Houston but filmed in Bavaria, Germany Futureworld (1976) – filmed at the Johnson Space Center facilities and Jones Hall Logan's Run (1976) – filmed inside the Houston Hyatt Regency The Bad News Bears in Breaking Training (1977) - filmed in the Astrodome as well as Bayland Park on 6400 Bissonnet Murder at the World Series (1977) – made-for-TV film Telefon (1977) – set in Houston but filmed on a Hollywood backlot, parts of Los Angeles and inside the Hyatt Regency at 5 Embarcadero in San Francisco FM (1978) – filmed at Greenway Plaza in Houston The Swarm (1978) - second unit scenes filmed on Memorial Drive, Astrodome, Interstate 45 South/McKinney Street Exit ramp, and the main lobby of 2 Houston Center Texas (1980–1982) – daytime soap opera, a spin-off of Another World Urban Cowboy (1980) - Filmed at the old Gilley's in Pasadena, Texas. Murder in Texas (1981) – made-for-TV film Student Bodies (1981) The Best Little Whorehouse in Texas (1982) – char