source stringlengths 31 227 | text stringlengths 9 2k |
|---|---|
https://en.wikipedia.org/wiki/Allylic%20strain | Allylic strain (also known as A1,3 strain, 1,3-allylic strain, or A-strain) in organic chemistry is a type of strain energy resulting from the interaction between a substituent on one end of an olefin (a synonym for an alkene) with an allylic substituent on the other end. If the substituents (R and R') are large enough in size, they can sterically interfere with each other such that one conformer is greatly favored over the other. Allylic strain was first recognized in the literature in 1965 by Johnson and Malhotra. The authors were investigating cyclohexane conformations including endocyclic and exocylic double bonds when they noticed certain conformations were disfavored due to the geometry constraints caused by the double bond. Organic chemists capitalize on the rigidity resulting from allylic strain for use in asymmetric reactions.
Quantifying allylic strain energy
The "strain energy" of a molecule is a quantity that is difficult to precisely define, so the meaning of this term can easily vary depending on one's interpretation. Instead, an objective way to view the allylic strain of a molecule is through its conformational equilibrium. Comparing the heats of formation of the involved conformers, an overall ΔHeq can be evaluated. This term gives information about the relative stabilities of the involved conformers and the effect allylic strain has one equilibrium. Heats of formation can be determined experimentally though calorimetric studies; however, calculated enthalpies are more commonly used due to the greater ease of acquisition.
Different methods utilized to estimate conformational equilibrium enthalpy include: the Westheimer method, the homomorph method, and more simply—using estimated enthalpies of nonbonded interactions within a molecule. Because all of these methods are approximations, reported strain values for the same molecule can vary and should be used only to give a general idea of the strain energy.
Olefins
The simplest type of molecules |
https://en.wikipedia.org/wiki/Divided%20power%20structure | In mathematics, specifically commutative algebra, a divided power structure is a way of making expressions of the form meaningful even when it is not possible to actually divide by .
Definition
Let A be a commutative ring with an ideal I. A divided power structure (or PD-structure, after the French puissances divisées) on I is a collection of maps for n = 0, 1, 2, ... such that:
and for , while for n > 0.
for .
for .
for , where is an integer.
for and , where is an integer.
For convenience of notation, is often written as when it is clear what divided power structure is meant.
The term divided power ideal refers to an ideal with a given divided power structure, and divided power ring refers to a ring with a given ideal with divided power structure.
Homomorphisms of divided power algebras are ring homomorphisms that respects the divided power structure on its source and target.
Examples
The free divided power algebra over on one generator:
If A is an algebra over then every ideal I has a unique divided power structure where Indeed, this is the example which motivates the definition in the first place.
If M is an A-module, let denote the symmetric algebra of M over A. Then its dual has a canonical structure of divided power ring. In fact, it is canonically isomorphic to a natural completion of (see below) if M has finite rank.
Constructions
If A is any ring, there exists a divided power ring
consisting of divided power polynomials in the variables
that is sums of divided power monomials of the form
with . Here the divided power ideal is the set of divided power polynomials with constant coefficient 0.
More generally, if M is an A-module, there is a universal A-algebra, called
with PD ideal
and an A-linear map
(The case of divided power polynomials is the special case in which M is a free module over A of finite rank.)
If I is any ideal of a ring A, there is a universal construction which extends A with divided powers of el |
https://en.wikipedia.org/wiki/Peter%20Cameron%20%28mathematician%29 | Peter Jephson Cameron FRSE (born 23 January 1947) is an Australian mathematician who works in group theory, combinatorics, coding theory, and model theory. He is currently half-time Professor of Mathematics at the University of St Andrews, and Emeritus Professor at Queen Mary University of London.
Cameron received a B.Sc. from the University of Queensland and a D.Phil. in 1971 from the University of Oxford as a Rhodes Scholar, with Peter M. Neumann as his supervisor. Subsequently, he was a Junior Research Fellow and later a Tutorial Fellow at Merton College, Oxford, and also lecturer at Bedford College, London.
Work
Cameron specialises in algebra and combinatorics; he has written books about combinatorics, algebra, permutation groups, and logic, and has produced over 350 academic papers. In 1988, he posed the Cameron–Erdős conjecture with Paul Erdős.
Honours and awards
He was awarded the London Mathematical Society's Whitehead Prize in 1979 and is joint winner of the 2003 Euler Medal. In 2008, he was selected as the Forder Lecturer of the LMS and New Zealand Mathematical Society. In 2018 he was elected a Fellow of the Royal Society of Edinburgh.
Books
Notes |
https://en.wikipedia.org/wiki/The%20Journey%20of%20Man | The Journey of Man: A Genetic Odyssey is a 2002 book by Spencer Wells, an American geneticist and anthropologist, in which he uses techniques and theories of genetics and evolutionary biology to trace the geographical dispersal of early human migrations out of Africa. The book was made into a TV documentary in 2003.
Synopsis
According to the recent single-origin hypothesis, human ancestors originated in Africa, and eventually made their way out to the rest of the world. Analysis of the Y chromosome is one of the methods used in tracing the history of early humans. Thirteen genetic markers on the Y-chromosome differentiate populations of human beings.
It is believed, on the basis of genetic evidence, that all human beings in existence now descend from one single man who lived in Africa about 60,000 years ago. The earliest groups of humans are believed to find their present-day descendants among the San people, a group that is now found in western southern Africa. The San are smaller than the Bantu. They have lighter skins, more tightly curled hair, and they share the epicanthal fold with the people of Central and South East Asia.
Southern and eastern Africa are believed to originally have been populated by people akin to the San. Since that early time much of their range has been taken over by the Bantu. Skeletal remains of these ancestral people are found in Paleolithic sites in Somalia and Ethiopia. There are also peoples in east Africa today who speak substantially different languages that nevertheless share the archaic characteristics of the San language, with its distinctive repertoire of click and pop sounds. These are the only languages in the entire world that use these sounds in speech.
As humans migrated out of Africa, they all carried a genetic marker on the Y chromosome known as M168 (Haplogroup CT (Y-DNA)).
The first wave of migration out of Africa stayed close to the oceans shores, tracing a band along the coastal areas of the Indian Ocean in |
https://en.wikipedia.org/wiki/Subacromial%20bursitis | Subacromial bursitis is a condition caused by inflammation of the bursa that separates the superior surface of the supraspinatus tendon (one of the four tendons of the rotator cuff) from the overlying coraco-acromial ligament, acromion, and coracoid (the acromial arch) and from the deep surface of the deltoid muscle. The subacromial bursa helps the motion of the supraspinatus tendon of the rotator cuff in activities such as overhead work.
Musculoskeletal complaints are one of the most common reasons for primary care office visits, and rotator cuff disorders are the most common source of shoulder pain.
Primary inflammation of the subacromial bursa is relatively rare and may arise from autoimmune inflammatory conditions such as rheumatoid arthritis, crystal deposition disorders such as gout or pseudogout, calcific loose bodies, and infection. More commonly, subacromial bursitis arises as a result of complex factors, thought to cause shoulder impingement symptoms. These factors are broadly classified as intrinsic (intratendinous) or extrinsic (extratendinous). They are further divided into primary or secondary causes of impingement. Secondary causes are thought to be part of another process such as shoulder instability or nerve injury.
In 1983 Neer described three stages of impingement syndrome. He noted that "the symptoms and physical signs in all three stages of impingement are almost identical, including the 'impingement sign'..., arc of pain, crepitus, and varying weakness". The Neer classification did not distinguish between partial-thickness and full-thickness rotator cuff tears in stage III. This has led to some controversy about the ability of physical examination tests to accurately diagnose between bursitis, impingement, impingement with or without rotator cuff tear and impingement with partial versus complete tears.
In 2005, Park et al. published their findings which concluded that a combination of clinical tests were more useful than a single physical e |
https://en.wikipedia.org/wiki/Davis%27s%20law | Davis's law is used in anatomy and physiology to describe how soft tissue models along imposed demands. It is similar to Wolff's law, which applies to osseous tissue. It is a physiological principle stating that soft tissue heal according to the manner in which they are mechanically stressed.
It is also an application of the Mechanostat model of Harold Frost which was originally developed to describe the adaptational response of bones; however – as outlined by Harold Frost himself – it also applies to fibrous collagenous connective tissues, such as ligaments, tendons and fascia. The "stretch-hypertrophy rule" of that model states: "Intermittent stretch causes collagenous tissues to hypertrophy until the resulting increase in strength reduces elongation in tension to some minimum level". Similar to the behavior of bony tissues this adaptational response occurs only if the mechanical strain exceeds a certain threshold value. Harold Frost proposed that for dense collagenous connective tissues the related threshold values are around 23 Newton/mm2 or 4% strain elongation.
Origin
The term Davis's law is named after Henry Gassett Davis, an American orthopedic surgeon known for his work in developing traction methods. Its earliest known appearance is in John Joseph Nutt's 1913 book Diseases and Deformities of the Foot, where Nutt outlines the law by quoting a passage from Davis's 1867 book, Conservative Surgery:
"Ligaments, or any soft tissue, when put under even a moderate degree of tension, if that tension is unremitting, will elongate by the addition of new material; on the contrary, when ligaments, or rather soft tissues, remain uninterruptedly in a loose or lax state, they will gradually shorten, as the effete material is removed, until they come to maintain the same relation to the bony structures with which they are united that they did before their shortening. Nature never wastes her time and material in maintaining a muscle or ligament at its original length w |
https://en.wikipedia.org/wiki/Random%20phase%20approximation | The random phase approximation (RPA) is an approximation method in condensed matter physics and in nuclear physics. It was first introduced by David Bohm and David Pines as an important result in a series of seminal papers of 1952 and 1953. For decades physicists had been trying to incorporate the effect of microscopic quantum mechanical interactions between electrons in the theory of matter. Bohm and Pines' RPA accounts for the weak screened Coulomb interaction and is commonly used for describing the dynamic linear electronic response of electron systems.
In the RPA, electrons are assumed to respond only to the total electric potential V(r) which is the sum of the external perturbing potential Vext(r) and a screening potential Vsc(r). The external perturbing potential is assumed to oscillate at a single frequency ω, so that the model yields via a self-consistent field (SCF) method a dynamic dielectric function denoted by εRPA(k, ω).
The contribution to the dielectric function from the total electric potential is assumed to average out, so that only the potential at wave vector k contributes. This is what is meant by the random phase approximation. The resulting dielectric function, also called the Lindhard dielectric function, correctly predicts a number of properties of the electron gas, including plasmons.
The RPA was criticized in the late 1950s for overcounting the degrees of freedom and the call for justification led to intense work among theoretical physicists. In a seminal paper Murray Gell-Mann and Keith Brueckner showed that the RPA can be derived from a summation of leading-order chain Feynman diagrams in a dense electron gas.
The consistency in these results became an important justification and motivated a very strong growth in theoretical physics in the late 50s and 60s.
Applications
Ground state of an interacting bosonic system
The RPA vacuum for a bosonic system can be expressed in terms of non-correlated bosonic vacuum and original boson |
https://en.wikipedia.org/wiki/Phase-contrast%20microscopy |
Phase-contrast microscopy (PCM) is an optical microscopy technique that converts phase shifts in light passing through a transparent specimen to brightness changes in the image. Phase shifts themselves are invisible, but become visible when shown as brightness variations.
When light waves travel through a medium other than a vacuum, interaction with the medium causes the wave amplitude and phase to change in a manner dependent on properties of the medium. Changes in amplitude (brightness) arise from the scattering and absorption of light, which is often wavelength-dependent and may give rise to colors. Photographic equipment and the human eye are only sensitive to amplitude variations. Without special arrangements, phase changes are therefore invisible. Yet, phase changes often convey important information.
Phase-contrast microscopy is particularly important in biology.
It reveals many cellular structures that are invisible with a bright-field microscope, as exemplified in the figure.
These structures were made visible to earlier microscopists by staining, but this required additional preparation and death of the cells.
The phase-contrast microscope made it possible for biologists to study living cells and how they proliferate through cell division. It is one of the few methods available to quantify cellular structure and components that does not use fluorescence.
After its invention in the early 1930s, phase-contrast microscopy proved to be such an advancement in microscopy that its inventor Frits Zernike was awarded the Nobel Prize in Physics in 1953.
Working principle
The basic principle to make phase changes visible in phase-contrast microscopy is to separate the illuminating (background) light from the specimen-scattered light (which makes up the foreground details) and to manipulate these differently.
The ring-shaped illuminating light (green) that passes the condenser annulus is focused on the specimen by the condenser. Some of the illuminating light |
https://en.wikipedia.org/wiki/Pulse%20shaping | In electronics and telecommunications, pulse shaping is the process of changing a transmitted pulses' waveform to optimize the signal for its intended purpose or the communication channel. This is often done by limiting the bandwidth of the transmission and filtering the pulses to control intersymbol interference. Pulse shaping is particularly important in RF communication for fitting the signal within a certain frequency band and is typically applied after line coding and modulation.
Need for pulse shaping
Transmitting a signal at high modulation rate through a band-limited channel can create intersymbol interference. The reason for this are Fourier correspondences (see Fourier transform). A bandlimited signal corresponds to an infinite time signal, that causes neighbouring pulses to overlap. As the modulation rate increases, the signal's bandwidth increases. As soon as the spectrum of the signal is a sharp rectangular, this leads to a sinc shape in the time domain. This happens if the bandwidth of the signal is larger than the channel bandwidth, leading to a distortion. This distortion usually manifests itself as intersymbol interference (ISI). Theoretically for sinc shaped pulses, there is no ISI, if neighbouring pulses are perfectly aligned, i.e. in the zero crossings of each other. But this requires a very good synchronization and precise/stable sampling without jitters. As a practical tool to determine ISI, one uses the Eye pattern, that visualizes typical effects of the channel and the synchronization/frequency stability.
The signal's spectrum is determined by the modulation scheme and data rate used by the transmitter, but can be modified with a pulse shaping filter. This pulse shaping will make the spectrum smooth, leading to a time limited signal again. Usually the transmitted symbols are represented as a time sequence of dirac delta pulses multiplied with the symbol. This is the formal transition from the digital to the analog domain. At this point, th |
https://en.wikipedia.org/wiki/Second%20voyage%20of%20HMS%20Beagle | The second voyage of HMS Beagle, from 27 December 1831 to 2 October 1836, was the second survey expedition of HMS Beagle, under captain Robert FitzRoy, who had taken over command of the ship on its first voyage after the previous captain, Pringle Stokes, committed suicide. FitzRoy had thought of the advantages of having someone onboard who could investigate geology, and sought a naturalist to accompany them as a supernumerary. At the age of 22, the graduate Charles Darwin hoped to see the tropics before becoming a parson, and accepted the opportunity. He was greatly influenced by reading Charles Lyell's Principles of Geology during the voyage. By the end of the expedition, Darwin had made his name as a geologist and fossil collector, and the publication of his journal (later known as The Voyage of the Beagle) gave him wide renown as a writer.
Beagle sailed across the Atlantic Ocean, and then carried out detailed hydrographic surveys around the coasts of southern South America, returning via Tahiti and Australia, after having circumnavigated the Earth. The initial offer to Darwin told him the voyage would last two years; it lasted almost five.
Darwin spent most of this time exploring on land: three years and three months land, 18 months at sea. Early in the voyage, Darwin decided that he could write a geology book, and he showed a gift for theorising. At Punta Alta in Argentina, he made a major find of gigantic fossils of extinct mammals, then known from very few specimens. He collected and made detailed observations of plants and animals. His findings undermined his belief in the doctrine that species are fixed, and provided the basis for ideas which came to him when back in England, leading to his theory of evolution by natural selection.
Aims of the expedition
When the Napoleonic Wars ended in 1815, the Pax Britannica saw seafaring nations competing in colonisation and rapid industrialisation. The logistics of supply and growing commerce needed reliable inform |
https://en.wikipedia.org/wiki/Tafel%20equation | The Tafel equation is an equation in electrochemical kinetics relating the rate of an electrochemical reaction to the overpotential. The Tafel equation was first deduced experimentally and was later shown to have a theoretical justification. The equation is named after Swiss chemist Julius Tafel." It describes how the electrical current through an electrode depends on the voltage difference between the electrode and the bulk electrolyte for a simple, unimolecular redox reaction ".
Where an electrochemical reaction occurs in two half reactions on separate electrodes, the Tafel equation is applied to each electrode separately. On a single electrode the Tafel equation can be stated as:
where
the plus sign under the exponent refers to an anodic reaction, and a minus sign to a cathodic reaction,
: overpotential, V
: "Tafel slope", V
: current density, A/m2
: "exchange current density", A/m2.
A verification plus further explanation for this equation can be found here. The Tafel equation is an approximation of the Butler-Volmer equation in the case of . "[ The Tafel equation ] assumes that the concentrations at the electrode are practically equal to the concentrations in the bulk electrolyte, allowing the current to be expressed as a function of potential only. In other words, it assumes that the electrode mass transfer rate is much greater than the reaction rate, and that the reaction is dominated by the slower chemical reaction rate ". Also, at a given electrode the Tafel equation assumes that the reverse half reaction rate is negligible compared to the forward reaction rate.
Overview of the terms
The exchange current is the current at equilibrium, i.e. the rate at which oxidized and reduced species transfer electrons with the electrode. In other words, the exchange current density is the rate of reaction at the reversible potential (when the overpotential is zero by definition). At the reversible potential, the reaction is in equilibrium meaning that the |
https://en.wikipedia.org/wiki/Schafer%20automation%20system | The first Schafer Automation System, installed at KGEE(AM) in Bakersfield, California in 1956, was dubbed the "blue-wire job" because all of the wiring in it was blue, its inventor, Paul Schafer said. "The owner wanted to program his station all night long without a person being there. I used a couple of Seeburg record player changers to play 45s and several Ampex reel decks for commercials and we were in business," Schafer said.
In the beginning
Originally, commercials had to be dubbed sequentially to play back in the right order. Before long, Schafer, with the help of Chief Engineer Jim Harford, designed a better system. The "spotter" used Ampex reel-to-reel tape decks that could fast forward and rewind to count windows cut from the tape in order to locate specific commercials. "We removed about an inch of the oxide from the tape every minute. The 'windows' were then counted by the automation system as they passed between a lamp and a photocell to find the right commercial to play," Schafer said.
The Schafer Automation System used a series of relays and stepping switches and a clock that allowed programmers to back-time music to join network newscasts without having to fade the music. Schafer said the automation system consisted of two racks: one held the "brain," another contained three tape reel-to-reel decks. The Seeburg record player changers held 100 records each.
Programming the system was limited at the beginning. The front control panel consisted of a series of pins to allow programmers to change a sequence or repeat it, Schafer said. "They could set up a pattern by screwing pins into any of the many holes in the clock. Typically this would be each 15 or 30 minutes to play station breaks," Schafer said.
Silence trigger
In the original Schafer Automation System, the switching from one event to the next was triggered by silence. "Whenever silence was sensed the system would step to the next event. There would be the occasional record with a pause that |
https://en.wikipedia.org/wiki/Superior%20fascia%20of%20the%20urogenital%20diaphragm | The superior fascia of the urogenital diaphragm is continuous with the obturator fascia and stretches across the pubic arch.
Structure
If the obturator fascia be traced medially after leaving the Obturator internus muscle, it will be found attached by some of its deeper or anterior fibers to the inner margin of the pubic arch, while its superficial or posterior fibers pass over this attachment to become continuous with the superior fascia of the urogenital diaphragm.
Behind, this layer of the fascia is continuous with the inferior fascia and with the fascia of Colles; in front it is continuous with the fascial sheath of the prostate, and is fused with the inferior fascia to form the transverse ligament of the pelvis.
Controversy
Some sources dispute that this structure exists. However, whether this layer is real or imagined, it still serves to describe a division of the contents of the perineum in many modern anatomy resources. |
https://en.wikipedia.org/wiki/Modal%20analysis%20using%20FEM | The goal of modal analysis in structural mechanics is to determine the natural mode shapes and frequencies of an object or structure during free vibration. It is common to use the finite element method (FEM) to perform this analysis because, like other calculations using the FEM, the object being analyzed can have arbitrary shape and the results of the
calculations are acceptable. The types of equations which arise from modal analysis are those seen in eigensystems. The physical interpretation of the eigenvalues and eigenvectors which come from solving the system are that
they represent the frequencies and corresponding mode shapes. Sometimes, the only desired modes are the lowest frequencies because they can be the most prominent modes at which the object will vibrate, dominating all the higher frequency
modes.
It is also possible to test a physical object to determine its natural frequencies and mode shapes. This is called an Experimental Modal Analysis. The results of the physical test can be used to calibrate a finite element model to determine if the underlying assumptions made were correct (for example, correct material properties and boundary conditions were used).
FEA eigensystems
For the most basic problem involving a linear elastic material which obeys Hooke's Law,
the matrix equations take the form of a dynamic three-dimensional spring mass system.
The generalized equation of motion is given as:
where is the mass matrix,
is the 2nd time derivative of the displacement
(i.e., the acceleration),
is the velocity, is a damping matrix,
is the stiffness matrix, and
is the force vector. The general problem, with nonzero damping, is a quadratic eigenvalue problem. However, for vibrational modal analysis, the damping is generally ignored, leaving only the 1st and 3rd terms on the left hand side:
This is the general form of the eigensystem encountered in structural
engineering using the FEM. To represent the free-vibration solutions of the structu |
https://en.wikipedia.org/wiki/Fibonacci%20numbers%20in%20popular%20culture | The Fibonacci numbers are a sequence of integers, starting with 0, 1 and continuing 1, 2, 3, 5, 8, 13, ..., each new number being the sum of the previous two. The Fibonacci numbers, often presented in conjunction with the golden ratio, are a popular theme in culture. They have been mentioned in novels, films, television shows, and songs. The numbers have also been used in the creation of music, visual art, and architecture.
Architecture
The sequence has been used in the design of a building, the Core, at the Eden Project, near St Austell, Cornwall, England.
Cinema
In The Phantom Tollbooth (1970), Milo (Butch Patrick) is given a set of numbers to identify in order to gain entry to the "Numbers Mine", and correctly answers noting that it is the Fibonacci sequence.
Along with the golden rectangle and golden spiral, the Fibonacci sequence is mentioned in Darren Aronofsky's independent film Pi (1998). They are used to find the name of God.
In The Da Vinci Code (2006), the numbers are used to unlock a safe. They are also placed out of order in a message to indicate that the message is also out of order (anagram).
In Mr. Magorium's Wonder Emporium (2007), Magorium hires accountant Henry Weston (Jason Bateman) after an interview in which he demonstrates knowledge of Fibonacci numbers.
In L: Change the World (2008), Near is seen arranging sugar cubes in a Fibonacci sequence.
In 21 (2008), the first seven numbers in the Fibonacci Sequence are drawn in icing on Ben's (Jim Sturgess) Birthday cake. The 8th term, 21, is left out. Ben and Miles (Josh Gad) quickly figure it out.
In Nymphomaniac (2013), the character Seligman (Stellan Skarsgård) notes that when Joe (Charlotte Gainsbourg) loses her virginity, the boy who deflowers her does so in a sequence of thrusts that are Fibonacci numbers.
In Arrival (2016), character Ian Donnelly (Jeremy Renner) checks if the aliens have communicated with humans in any of the following approaches: "shapes, patterns, numbers, fibonacc |
https://en.wikipedia.org/wiki/Tricholoma%20argyraceum | Tricholoma argyraceum is a grey-capped mushroom of the large genus Tricholoma. It has been often confused with the similar-looking Tricholoma scalpturatum.
Taxonomy
French mycologist Pierre Bulliard described this species as Agaricus argyraceus in 1779, before his countryman Claude Casimir Gillet gave it its current name in 1874. The generic name derives from the Greek trichos/τριχος 'hair' and loma/λωμα 'hem', 'fringe' or 'border'. It lies within the section Terrea within the subgenus Tricholoma within the genus Tricholoma.
Description
The cap is conical initially and flattening to a convex shape, with a prominent boss. Measuring in diameter, it is covered with greyish scales, paler than other grey-capped tricholomas, and the crowded gills are white or pale grey and emarginate or adnate in cross section. They sometimes stain yellowish when bruised. The thin flesh is cream or white and has a farinaceous (floury) and somewhat rancid taste and smell. The whitish stipe is high and wide and has no ring and a tapering base.
The poisonous T. pardinum is similar in appearance but with coarser scales on its cap. T.scalpturatum has a darker cap without a boss.
Distribution and habitat
Tricholoma argyraceum occurs across Europe but is uncommon overall. The fruit bodies appear from June to December (occasionally earlier in Spring). The species has an ectomycorrhizal association with a number of genera – birch (Betula), Carpinus, oak (Quercus) and Tilia.
Synonyms
Obsolete synonyms for Tricholoma argyraceum include:
Agaricus argyraceus Bull. 1779
Agaricus myomyces var. argyraceus (Bull.) Pers. 1801
Tricholoma argyraceum f. inocybeoides (A. Pearson) Mort. Chr. & Noordel. 1999
Tricholoma argyraceum var. inocybeoides (A. Pearson) Krieglst. 1991
Tricholoma inocybeoides A. Pearson 1938
Tricholoma myomyces var. argyraceum (Bull.) J.E. Lange 1933
Tricholoma scalpturatum var. argyraceum (Bull.) Kühner & Romagn. 1953
Tricholoma terreum var. argyraceum (Bull.) P. Kumm. 1871
Edib |
https://en.wikipedia.org/wiki/Tricholoma%20sulphureum | Tricholoma sulphureum, also known as the stinker, sulphur knight or gas agaric, is an inedible or mildly poisonous mushroom found in woodlands in Europe. It has a distinctive bright yellow colour and an unusual smell likened to coal gas. It occurs in deciduous woodlands in Europe from spring to autumn.
Taxonomy
Tricholoma sulphureum was first described in 1784 by the French botanist Pierre Bulliard and given the name Agaricus sulphureus, before being placed in the genus Tricholoma by German mycologist Paul Kummer in 1871. The specific epithet sulfǔrěus derived from the Latin 'of or pertaining to sulfur'. It belongs to a complex of similar foul-smelling species such as the very similar Tricholoma inamoenum. Another related species, T. bufonium, may be an intraspecific variant.
Description
It has a convex cap with a vague umbo up to across, sulphur yellow in colour. The thick, sinuate gills, stipe and flesh are similarly bright yellow. The smell, caused by the chemical skatole, is enough to distinguish it from other yellow fungi. John Ramsbottom reports that it has a complex smell that has been likened variously to Jasmine, Narcissus, Hyacinth, Hemerocallis flava, Lilac, Tagetes, decayed hemp or coal gas, as well as described as nauseating or foetid. The taste is bitter.
It could be confused with the darker T. equestre, though the latter has a sticky cap, white flesh, thin crowded gills, and a mealy smell. However this latter species which was formerly considered a good edible mushroom, would have itself caused sporadic cases of poisoning.
Distribution and habitat
Tricholoma sulphureum is found in deciduous woods, particularly beech, and can occur anytime from spring until autumn. It is found across Europe and has been confirmed as far east as China. It is also distributed in North America, where it grows also with conifers. It is commonly known as the "Stinker" or "Sulfur Trich". In Turkey, it is considered critically endangered.
Toxicity
The fungus is usually |
https://en.wikipedia.org/wiki/Gerschenkron%20effect | The Gerschenkron effect, developed by Alexander Gerschenkron, claims that changing the base year for an index determines the growth rate of the index. This effect is applicable only to aggregation method using reference price structure (meaning, each country’s quantities are valued by uniform set of prices to obtain volume) or reference volume structure (meaning, obtaining Purchasing power parity via valuation of uniform set of quantities by each country’s price). However, if production is measured by "real" tearms, this effect does not exist.
This description is from the OECD website:
Simply, put the “Gerschenkron effect” measures the difference between Paasche and Laspeyres indices. That means that “early-weighted” aggregate will grow faster than “late-weighted.” Negative correlation is due to relatively rapid technical progress and falling relative price benefit from cost-reducing substitution. Or it can be vice versa; slow technical progress, increasing relative price suffer from cost-reducing substitution. In other words, this effect arises when activities whose relative prices are falling tend to increase their volume shares of total production and vice versa. Which is exactly what happened during industrial revolution when manufacturing expanded is produced volume.
After revision by Jonas and Sardy in 1970, properties of the Gerschenkron effect were further developed. In addition to originally stated upward bias of base-year indices and reasoning behind that, it was shown that the movement in relative quantities is usually larger than the movement in relative prices and that the weighted correlation of those effects decreases over time with further development.
History
What is now called the “Gerschenkron effect” have first appeared in 1947 and was further explained and used in a study A Dollar Index of Soviet Machinery Output in 1951 by Alexander Gerschenkron. Using actual data of United States machinery output in different years, it, empirically, sh |
https://en.wikipedia.org/wiki/Costa%27s%20minimal%20surface | In mathematics, Costa's minimal surface, is an embedded minimal surface discovered in 1982 by the Brazilian mathematician Celso José da Costa. It is also a surface of finite topology, which means that it can be formed by puncturing a compact surface. Topologically, it is a thrice-punctured torus.
Until its discovery, the plane, helicoid and the catenoid were believed to be the only embedded minimal surfaces that could be formed by puncturing a compact surface. The Costa surface evolves from a torus, which is deformed until the planar end becomes catenoidal. Defining these surfaces on rectangular tori of arbitrary dimensions yields the Costa surface. Its discovery triggered research and discovery into several new surfaces and open conjectures in topology.
The Costa surface can be described using the Weierstrass zeta and the Weierstrass elliptic functions. |
https://en.wikipedia.org/wiki/MODELLER | Modeller, often stylized as MODELLER, is a computer program used for homology modeling to produce models of protein tertiary structures and quaternary structures (rarer). It implements a method inspired by nuclear magnetic resonance spectroscopy of proteins (protein NMR), termed satisfaction of spatial restraints, by which a set of geometrical criteria are used to create a probability density function for the location of each atom in the protein. The method relies on an input sequence alignment between the target amino acid sequence to be modeled and a template protein which structure has been solved.
The program also incorporates limited functions for ab initio structure prediction of loop regions of proteins, which are often highly variable even among homologous proteins and thus difficult to predict by homology modeling.
Modeller was originally written and is currently maintained by Andrej Sali at the University of California, San Francisco. It runs on the operating systems Unix, Linux, macOS, and Windows. It is freeware for academic use. Graphical user interfaces (GUIs) and commercial versions are distributed by Accelrys. The ModWeb comparative protein structure modeling webserver is based on Modeller and other tools for automatic protein structure modeling, with an option to deposit the resulting models into ModBase. Due to Modeller's popularity, several third party GUIs for MODELLER are available:
EasyModeller is freeware and is one of the earliest third party GUIs for Modeller. Recent version (EasyModeller 4.0) supports Linux and Windows operating system.
UCSF Chimera has a simple interface to Modeller.
PyMod is a free and open-source plugin for PyMOL and has a comprehensive interface for Modeller. It supports Linux, Windows and macOS.
MaxMod is a standalone GUI for MODELLER on Windows.
See also
List of protein structure prediction software |
https://en.wikipedia.org/wiki/Low-energy%20adaptive%20clustering%20hierarchy | Low-energy adaptive clustering hierarchy ("LEACH") is a TDMA-based MAC protocol which is integrated with clustering and a simple routing protocol in wireless sensor networks (WSNs). The goal of LEACH is to lower the energy consumption required to create and maintain clusters in order to improve the life time of a wireless sensor network.
Protocol
LEACH is a hierarchical protocol in which most nodes transmit to cluster heads, and the cluster heads aggregate and compress the data and forward it to the base station (sink). Each node uses a stochastic algorithm at each round to determine whether it will become a cluster head in this round. LEACH assumes that each node has a radio powerful enough to directly reach the base station or the nearest cluster head, but that using this radio at full power all the time would waste energy.
Nodes that have been cluster heads cannot become cluster heads again for P rounds, where P is the desired percentage of cluster heads. Thereafter, each node has a 1/P probability of becoming a cluster head again. At the end of each round, each node that is not a cluster head selects the closest cluster head and joins that cluster. The cluster head then creates a schedule for each node in its cluster to transmit its data.
All nodes that are not cluster heads only communicate with the cluster head in a TDMA fashion, according to the schedule created by the cluster head. They do so using the minimum energy needed to reach the cluster head, and only need to keep their radios on during their time slot.
LEACH also uses CDMA so that each cluster uses a different set of CDMA codes, to minimize interference between clusters.
Properties
Properties of this algorithm include:
Cluster based
Random cluster head selection each round with rotation. Or cluster head selection based on sensor having highest energy
Cluster membership adaptive
Data aggregation at cluster head
Cluster head communicate directly with sink or user
Communication done with cl |
https://en.wikipedia.org/wiki/Sclerochronology | Sclerochronology is the study of periodic physical and chemical features in the hard tissues of animals that grow by accretion, including invertebrates and coralline red algae, and the temporal context in which they formed. It is particularly useful in the study of marine paleoclimatology. The term was coined in 1974 following pioneering work on nuclear test atolls by Knutson and Buddemeier and comes from the three Greek words skleros (hard), chronos (time) and logos (science), which together refer to the use of the hard parts of living organisms to order events in time. It is, therefore, a form of stratigraphy. Sclerochronology focuses primarily upon growth patterns reflecting annual, monthly, fortnightly, tidal, daily, and sub-daily (ultradian) increments of time.
The regular time increments are controlled by biological clocks, which, in turn, are caused by environmental and astronomical pacemakers.
Familiar examples include:
annual bandings in reef coral skeletons
annual, fortnightly, daily and ultradian growth increments in mollusk shells
annual bandings in the ear bones of fish, called otoliths.
Sclerochronology is analogous to dendrochronology, the study of annual rings in trees, and equally seeks to deduce organismal life history traits as well as to reconstruct records of environmental and climatic change through space and time.
Use in paleoclimatic study
The science of sclerochronology as applied to hard parts of various organism groups is now routinely used for paleoceanographic and paleoclimate reconstructions. The study includes isotopic and elemental proxies, sometimes termed sclerochemistry.
Improvements in imaging techniques have now realised the potential to decipher coral banding at daily resolution, although biological 'vital' effects may blur the climate signal at such a high resolution.
See also
Paleoceanography |
https://en.wikipedia.org/wiki/Perso-Arabic%20Script%20Code%20for%20Information%20Interchange | Perso-Arabic Script Code for Information Interchange (PASCII) is one of the Indian government standards for encoding languages using writing systems based on Perso-Arabic alphabet, in particular Kashmiri, Persian, Sindhi and Urdu. The ISCII encoding was originally intended to cover both the Brahmi-derived writing systems of India and the Arabic-based systems, but it was subsequently decided to encode the Arabic-based writing systems separately.
PASCII has not been widely used outside certain government institutions and has now been rendered largely obsolete by Unicode. Unicode uses a separate block for each writing system and largely preserves the PASCII layout within each block.
Codepage layout
The following table shows the character set for PASCII. Each character is shown with its decimal code and its Unicode equivalent. |
https://en.wikipedia.org/wiki/Mixmaster%20universe | The Mixmaster universe (named after Sunbeam Mixmaster, a brand of Sunbeam Products electric kitchen mixer) is a solution to Einstein field equations of general relativity studied by Charles Misner in an effort to better understand the dynamics of the early universe. He hoped to solve the horizon problem in a natural way by showing that the early universe underwent an oscillatory, chaotic epoch.
Discussion
The model is similar to the closed Friedmann–Lemaître–Robertson–Walker universe, in that spatial slices are positively curved and are topologically three-spheres . However, in the FRW universe, the can only expand or contract: the only dynamical parameter is overall size of the , parameterized by the scale factor . In the Mixmaster universe, the can expand or contract, but also distort anisotropically. Its evolution is described by a scale factor as well as by two shape parameters . Values of the shape parameters describe distortions of the that preserve its volume and also maintain a constant Ricci curvature scalar. Therefore, as the three parameters assume different values, homogeneity but not isotropy is preserved.
The model has a rich dynamical structure. Misner showed that the shape parameters act like the coordinates of a point mass moving in a triangular potential with steeply rising walls with friction. By studying the motion of this point, Misner showed that the physical universe would expand in some directions and contract in others, with the directions of expansion and contraction changing repeatedly. Because the potential is roughly triangular, Misner suggested that the evolution is chaotic.
Metric
The metric studied by Misner (very slightly modified from his notation) is given by,
where
and the , considered as differential forms, are defined by
In terms of the coordinates . These satisfy
where is the exterior derivative and the wedge product of differential forms. The 1-forms form a left-invariant co-frame on the Lie group SU(2), whic |
https://en.wikipedia.org/wiki/Lindel%C3%B6f%27s%20theorem | In mathematics, Lindelöf's theorem is a result in complex analysis named after the Finnish mathematician Ernst Leonard Lindelöf. It states that a holomorphic function on a half-strip in the complex plane that is bounded on the boundary of the strip and does not grow "too fast" in the unbounded direction of the strip must remain bounded on the whole strip. The result is useful in the study of the Riemann zeta function, and is a special case of the Phragmén–Lindelöf principle. Also, see Hadamard three-lines theorem.
Statement of the theorem
Let be a half-strip in the complex plane:
Suppose that is holomorphic (i.e. analytic) on and that there are constants
, , and such that
and
Then is bounded by on all of :
Proof
Fix a point inside . Choose , an integer and large enough such that
. Applying maximum modulus principle to the function and
the rectangular area we obtain , that is, . Letting yields
as required. |
https://en.wikipedia.org/wiki/Critical%20mass%20%28sociodynamics%29 | In social dynamics, critical mass is a sufficient number of adopters of a new idea, technology or innovation in a social system so that the rate of adoption becomes self-sustaining and creates further growth. The point at which critical mass is achieved is sometimes referred to as a threshold within the threshold model of statistical modeling.
The term critical mass is borrowed from nuclear physics, where it refers to the amount of a substance needed to sustain a chain reaction. Within social sciences, critical mass has its roots in sociology and is often used to explain the conditions under which reciprocal behavior is started within collective groups, and how reciprocal behavior becomes self-sustaining. Recent technology research in platform ecosystems shows that apart from the quantitative notion of a “sufficient number”, critical mass is also influenced by qualitative properties such as reputation, interests, commitments, capabilities, goals, consensuses, and decisions, all of which are crucial in determining whether reciprocal behavior can be started to achieve sustainability to a commitment such as an idea, new technology, or innovation.
Other social factors that are important include the size of; and inter-dependencies and level of communication in a society or one of its subcultures. Another is social stigma, or the possibility of public advocacy due to such a factor. Critical mass is a concept used in a variety of contexts, including physics, group dynamics, politics, public opinion, and technology.
History
The concept of critical mass was originally created by game theorist Thomas Schelling and sociologist Mark Granovetter to explain the actions and behaviors of a wide range of people and phenomenon. The concept was first established (although not explicitly named) in Schelling's essay about racial segregation in neighborhoods, "Dynamic models of segregation", published in 1971 in the Journal of Mathematical Sociology, and later refined in his book, Mi |
https://en.wikipedia.org/wiki/Orienting%20system | The brain pathway that orients visual attention to a stimulus is referred to as the orienting system. There are two main types of visual orientations, covert (exogenous) which occurs when a salient environmental change causes a shift in attention and overt (endogenous) which occurs when the individual makes a conscious decision to orient attention to a stimuli During a covert orientation of attention, the individual does not physically move, and during an overt orientation of attention the individual's eyes and head physically move in the direction of the stimulus.
Information acquired through covert and overt visual orientations travels through the norepinephrine system, indirectly effecting the ventral visual pathway. The four specific brain regions involved in this process are the frontal eye field, the temporoparietal junction, the pulvinar, and the superior colliculus. The frontal eye field is involved in goal-driven eye movements and can inhibit stimulus driven eye movements. The temporoparietal junction appears to be involved location-cueing tasks, and individuals with lesions in this area have difficulty with attentional reorienting. The pulvinar is located posterior to the thalamus and its role in the orientating system is still being researched; however it is thought to be involved in covert orienting. Finally, the superior colliculus provides information about the location of the stimuli to which attention is directed. |
https://en.wikipedia.org/wiki/Monadic%20predicate%20calculus | In logic, the monadic predicate calculus (also called monadic first-order logic) is the fragment of first-order logic in which all relation symbols in the signature are monadic (that is, they take only one argument), and there are no function symbols. All atomic formulas are thus of the form , where is a relation symbol and is a variable.
Monadic predicate calculus can be contrasted with polyadic predicate calculus, which allows relation symbols that take two or more arguments.
Expressiveness
The absence of polyadic relation symbols severely restricts what can be expressed in the monadic predicate calculus. It is so weak that, unlike the full predicate calculus, it is decidable—there is a decision procedure that determines whether a given formula of monadic predicate calculus is logically valid (true for all nonempty domains). Adding a single binary relation symbol to monadic logic, however, results in an undecidable logic.
Relationship with term logic
The need to go beyond monadic logic was not appreciated until the work on the logic of relations, by Augustus De Morgan and Charles Sanders Peirce in the nineteenth century, and by Frege in his 1879 Begriffsschrifft. Prior to the work of these three men, term logic (syllogistic logic) was widely considered adequate for formal deductive reasoning.
Inferences in term logic can all be represented in the monadic predicate calculus. For example the argument
All dogs are mammals.
No mammal is a bird.
Thus, no dog is a bird.
can be notated in the language of monadic predicate calculus as
where , and denote the predicates of being, respectively, a dog, a mammal, and a bird.
Conversely, monadic predicate calculus is not significantly more expressive than term logic. Each formula in the monadic predicate calculus is equivalent to a formula in which quantifiers appear only in closed subformulas of the form
or
These formulas slightly generalize the basic judgements considered in term logic. For example, this |
https://en.wikipedia.org/wiki/The%20Design%20of%20an%20Optimizing%20Compiler | The Design of an Optimizing Compiler (Elsevier Science Ltd, 1980, ), by William Wulf, Richard K. Johnson, Charles B. Weinstock, Steven O. Hobbs, and Charles M. Geschke, was published in 1975 by Elsevier. It describes the BLISS optimizing compiler for the PDP-11, written at Carnegie Mellon University in the early 1970s. The compiler ran on a PDP-10 and was one of the first to produce well-optimized code for a minicomputer. Because of its elegant design and the quality of the generated code, the compiler and book remain classics in the compiler field.
Although the original book has been out of print for many years, a print on demand version remains available from University Microfilms International.
Reception
Software: Practice and Experience said compiling experts would benefit the most with The Design of an Optimizing Compiler. |
https://en.wikipedia.org/wiki/George%20B.%20Thomas | George Brinton Thomas Jr. (January 11, 1914 – October 31, 2006) was an American mathematician and professor of mathematics at MIT. Internationally, he is best known for being the author of the widely used calculus textbook Calculus and Analytical Geometry, known today as Thomas' Calculus.
Early life
Born in Boise, Idaho, Thomas' early years were difficult. His father, George Brinton Thomas Sr., was a bank employee, and his mother, Georgia Fay Thomas (née Goin), died in the 1919 Influenza Epidemic, just eight days before his fifth birthday. His father remarried shortly thereafter, to Lena Steward. They lived in a tent with a wooden floor and a coal stove.
After his stepmother Lena died from complications due to childbirth, the father and son moved to the Spokane Valley in Washington State, where they both attended Spokane University. George Thomas Sr. married again, to Gertrude Alice Johnson. Thomas began attending Washington State College (now Washington State University), after Spokane University went bankrupt. There, he earned a B.A. in 1934 and an M.A. in 1936, both in mathematics and mathematics education.
On August 15, 1936, Thomas married Jane Heath at her family's home in South Bend, Washington. The couple lived in Pullman, Washington for a year; Thomas worked at a local shoe store to save money for further graduate education.
In 1937, Thomas was accepted into the graduate mathematics program at Cornell University. At Cornell, Thomas worked as an instructor while pursuing his research in number theory.
Academic career
Thomas finished his doctoral work in 1940 and was immediately hired by MIT for a one-year teaching appointment. He was well liked at MIT, and was invited to join the faculty after his teaching fellowship ended.
During the Second World War, Thomas was involved in early computation systems and programmed the differential analyzer to calculate firing tables for the Navy.
In 1952, George and Jane Thomas moved into the Conantum comm |
https://en.wikipedia.org/wiki/Gliotoxin | Gliotoxin is a sulfur-containing mycotoxin that belongs to a class of naturally occurring 2,5-diketopiperazines produced by several species of fungi, especially those of marine origin. It is the most prominent member of the epipolythiopiperazines, a large class of natural products featuring a diketopiperazine with di- or polysulfide linkage. These highly bioactive compounds have been the subject of numerous studies aimed at new therapeutics. Gliotoxin was originally isolated from Gliocladium fimbriatum, and was named accordingly. It is an epipolythiodioxopiperazine metabolite that is one of the most abundantly produced metabolites in human invasive Aspergillosis (IA).
Occurrence
The compound is produced by human pathogens such as Aspergillus fumigatus, and also by species of Trichoderma and Penicillium. Gliotoxin has also been reported from yeasts of the genus Candida, but results from other studies have cast doubt on the production of this metabolite by Candida fungi. Gliotoxin is not produced by nonpathogenic A. fischeri although A.fischeri contains a gene cluster that is homologous to the gliotoxin gene cluster found in the pathogenic A. fumigatus. Gliotoxin contributes to the pathogenicity of opportunistic fungi by suppressing the immune system response of its host. Gliotoxin additionally possesses fungicidal and bacteriostatic properties, which indicates that it likely plays an important self defense role against bacteria and other fungi for the fungi that produce gliotoxin. Exposure of A. fumigatus to exogenous gliotoxin resulted in aberrant protein expression, especially in those strains that lacked the self-protection protein GliT. There is additional evidence for differential gliotoxin sensitivities amongst fungi including Aspergillus flavus, Fusarium graminearum, and Aspergillus oryzae.
Discovery
Gliotoxin was first described in 1936 by Weindling and Emerson as a metabolic product from the fungus Trichoderma lignorum. However, afterwards Weindling |
https://en.wikipedia.org/wiki/Moore%20space%20%28topology%29 | In mathematics, more specifically point-set topology, a Moore space is a developable regular Hausdorff space. That is, a topological space X is a Moore space if the following conditions hold:
Any two distinct points can be separated by neighbourhoods, and any closed set and any point in its complement can be separated by neighbourhoods. (X is a regular Hausdorff space.)
There is a countable collection of open covers of X, such that for any closed set C and any point p in its complement there exists a cover in the collection such that every neighbourhood of p in the cover is disjoint from C. (X is a developable space.)
Moore spaces are generally interesting in mathematics because they may be applied to prove interesting metrization theorems. The concept of a Moore space was formulated by R. L. Moore in the earlier part of the 20th century.
Examples and properties
Every metrizable space, X, is a Moore space. If {A(n)x} is the open cover of X (indexed by x in X) by all balls of radius 1/n, then the collection of all such open covers as n varies over the positive integers is a development of X. Since all metrizable spaces are normal, all metric spaces are Moore spaces.
Moore spaces are a lot like regular spaces and different from normal spaces in the sense that every subspace of a Moore space is also a Moore space.
The image of a Moore space under an injective, continuous open map is always a Moore space. (The image of a regular space under an injective, continuous open map is always regular.)
Both examples 2 and 3 suggest that Moore spaces are similar to regular spaces.
Neither the Sorgenfrey line nor the Sorgenfrey plane are Moore spaces because they are normal and not second countable.
The Moore plane (also known as the Niemytski space) is an example of a non-metrizable Moore space.
Every metacompact, separable, normal Moore space is metrizable. This theorem is known as Traylor’s theorem.
Every locally compact, locally connected normal Moore space is metrizable. |
https://en.wikipedia.org/wiki/Symmetry%20element | In chemistry and crystallography, a symmetry element is a point, line, or plane about which symmetry operations can take place. In particular, a symmetry element can be a mirror plane, an axis of rotation (either proper and improper), or a center of inversion. For an object such as a molecule or a crystal, a symmetry element corresponds to a set of symmetry operations, which are the rigid transformations employing the symmetry element that leave the object unchanged. The set containing these operations form one of the symmetry groups of the object. The elements of this symmetry group should not be confused with the "symmetry element" itself. Loosely, a symmetry element is the geometric set of fixed points of a symmetry operation. For example, for rotation about an axis, the points on the axis do not move and in a reflection the points that remain unchanged make up a plane of symmetry.
Identity
The identity symmetry element is found in all objects and is denoted E. It corresponds to an operation of doing nothing to the object. Because every molecule is indistinguishable from itself if nothing is done to it, every object possesses at least the identity element. An object having no symmetry elements other than E is called asymmetric. Such an object is necessarily chiral.
Mirror planes
Mirror planes are denoted by σ. In a molecule that also has an axis of symmetry, a mirror plane that includes the axis is called a vertical mirror plane and is labeled σ , while one perpendicular to the axis is called a horizontal mirror plane and is labeled σ . A vertical mirror plane that bisects the angle between two C2 axes is called a dihedral mirror plane, σ .
Rotational symmetry
Rotational symmetry, also known as radial symmetry, is represented by an axis about which the object rotates in its corresponding symmetry operation. A group of proper rotations is denoted as C, where the degrees of rotation that restore the object is 360/n (C= 180º rotation, C= 120º rotation, C= 9 |
https://en.wikipedia.org/wiki/Uterosacral%20ligament | The uterosacral ligaments (or rectouterine ligaments) are major ligaments of uterus that extend posterior-ward from the cervix to attach onto the (anterior aspect of the) sacrum.
Anatomy
Microanatomy/histology
The uterosacral ligaments consist of fibrous connective tissue, and smooth muscle tissue.
Relations
The uterosacral ligaments pass inferior to the peritoneum. They embrace the rectouterine pouch, and rectum. The pelvic splanchnic nerves run on top of the ligament.
Function
The uterosacral ligaments pull the cervix posterior-ward, counteracting the anterior-ward pull exerted by the round ligament of uterus upon the fundus of the uterus, thus maintaining anteversion of the body of the uterus.
Clinical significance
The uterosacral ligaments may be palpated during a rectal examination, but not during pelvic examination. |
https://en.wikipedia.org/wiki/L-arabinose%20operon | The L-arabinose operon, also called the ara or araBAD operon''', is an operon required for the breakdown of the five-carbon sugar L-arabinose in Escherichia coli. The L-arabinose operon contains three structural genes: araB, araA, araD (collectively known as araBAD), which encode for three metabolic enzymes that are required for the metabolism of L-arabinose. AraB (ribulokinase), AraA (an isomerase), and AraD (an epimerase) produced by these genes catalyse conversion of L-arabinose to an intermediate of the pentose phosphate pathway, D-xylulose-5-phosphate.
The structural genes of the L-arabinose operon are transcribed from a common promoter into a single transcript, a mRNA. The expression of the L-arabinose operon is controlled as a single unit by the product of regulatory gene araC and the catabolite activator protein (CAP)-cAMP complex. The regulator protein AraC is sensitive to the level of arabinose and plays a dual role as both an activator in the presence of arabinose and a repressor in the absence of arabinose to regulate the expression of araBAD. AraC protein not only controls the expression of araBAD but also auto-regulates its own expression at high AraC levels.
Structure
L-arabinose operon is composed of structural genes and regulatory regions including the operator region (araO1, araO2) and the initiator region (araI1, araI2). The structural genes, araB, araA and araD, encode enzymes for L-arabinose catabolism. There is also a CAP binding site where CAP-cAMP complex binds to and facilitates catabolite repression, and results in positive regulation of araBAD when the cell is starved of glucose.
The regulatory gene, araC, is located upstream of the L-arabinose operon and encodes the arabinose-responsive regulatory protein AraC. Both araC and araBAD have a discrete promoter where RNA polymerase binds and initiates transcription. araBAD and araC are transcribed in opposite directions from the araBAD promoter (PBAD) and araC promoter (PC) respectively.
|
https://en.wikipedia.org/wiki/Continuous%20knapsack%20problem | In theoretical computer science, the continuous knapsack problem (also known as the fractional knapsack problem) is an algorithmic problem in combinatorial optimization in which the goal is to fill a container (the "knapsack") with fractional amounts of different materials chosen to maximize the value of the selected materials. It resembles the classic knapsack problem, in which the items to be placed in the container are indivisible; however, the continuous knapsack problem may be solved in polynomial time whereas the classic knapsack problem is NP-hard. It is a classic example of how a seemingly small change in the formulation of a problem can have a large impact on its computational complexity.
Problem definition
An instance of either the continuous or classic knapsack problems may be specified by the numerical capacity of the knapsack, together with a collection of materials, each of which has two numbers associated with it: the weight of material that is available to be selected and the total value of that material. The goal is to choose an amount of each material, subject to the capacity constraint
and maximizing the total benefit
In the classic knapsack problem, each of the amounts must be either zero or ; the continuous knapsack problem differs by allowing to range continuously from zero to .
Some formulations of this problem rescale the variables to be in the range from 0 to 1. In this case the capacity constraint becomes
and the goal is to maximize the total benefit
Solution technique
The continuous knapsack problem may be solved by a greedy algorithm, first published in 1957 by George Dantzig, that considers the materials in sorted order by their values per unit weight. For each material, the amount xi is chosen to be as large as possible:
If the sum of the choices made so far equals the capacity W, then the algorithm sets xi = 0.
If the difference d between the sum of the choices made so far and W is smaller than wi, then the algorithm sets |
https://en.wikipedia.org/wiki/Isobutyraldehyde | Isobutyraldehyde is the chemical compound with the formula (CH3)2CHCHO. It is an aldehyde, isomeric with n-butyraldehyde (butanal). Isobutyraldehyde is made, often as a side-product, by the hydroformylation of propene. Its odour is described as that of wet cereal or straw. It undergoes the Cannizaro reaction even though it has alpha hydrogen atom. It is a colorless volatile liquid.
Synthesis
Isobutyraldehyde is produced industrially by the hydroformylation of propene. Several million tons are produced annually.
Biological routes
In the context of butanol fuel, isobutyraldehyde is of interest as a precursor to isobutanol. E. coli as well as several other organisms has been genetically modified to produce isobutanol. α-Ketoisovalerate, derived from oxidative deamination of valine, is prone to decarboxylation to give isobutyraldehyde, which is susceptible to reduction to the alcohol:
(CH3)2CHC(O)CO2H → (CH3)2CHCHO + CO2
(CH3)2CHCHO + NADH + H+ → (CH3)2CHCH2OH + NAD+
Other routes
It can also be produced using engineered bacteria.
Strong mineral acids catalyse the rearrangement of methallyl alcohol to isobutyraldehyde.
Reactions
Hydrogenation of the aldehyde gives isobutanol. Oxidation gives methacrolein or methacrylic acid. Condensation with formaldehyde gives hydroxypivaldehyde. The latter is a precursor to vitamin B5. |
https://en.wikipedia.org/wiki/Borirane | Borirane is a heterocyclic organic compound with the formula C2H4BH. This colourless, flammable gas is the simplest borirane, a three-membered ring consisting of two carbon and one boron atom. It can be viewed as a structural analog of aziridine, with boron replacing the nitrogen atom of aziridine. Borirane is isomeric with ethylideneborane.
This compound has five isomers. |
https://en.wikipedia.org/wiki/Extendible%20hashing | Extendible hashing is a type of hash system which treats a hash as a bit string and uses a trie for bucket lookup. Because of the hierarchical nature of the system, re-hashing is an incremental operation (done one bucket at a time, as needed). This means that time-sensitive applications are less affected by table growth than by standard full-table rehashes.
Extendible hashing was described by Ronald Fagin in 1979. Practically all modern filesystems use either extendible hashing or B-trees. In particular, the Global File System, ZFS, and the SpadFS filesystem use extendible hashing.
Example
Assume that the hash function returns a string of bits. The first i bits of each string will be used as indices to figure out where they will go in the "directory" (hash table). Additionally, i is the smallest number such that the index of every item in the table is unique.
Keys to be used:
Let's assume that for this particular example, the bucket size is 1. The first two keys to be inserted, k1 and k2, can be distinguished by the most significant bit, and would be inserted into the table as follows:
Now, if k3 were to be hashed to the table, it wouldn't be enough to distinguish all three keys by one bit (because both k3 and k1 have 1 as their leftmost bit). Also, because the bucket size is one, the table would overflow. Because comparing the first two most significant bits would give each key a unique location, the directory size is doubled as follows:
And so now k1 and k3 have a unique location, being distinguished by the first two leftmost bits. Because k2 is in the top half of the table, both 00 and 01 point to it because there is no other key to compare to that begins with a 0.
The above example is from .
Further detail
Now, k4 needs to be inserted, and it has the first two bits as 01..(1110), and using a 2 bit depth in the directory, this maps from 01 to Bucket A. Bucket A is full (max size 1), so it must be split; because there is more than one pointer to Bucke |
https://en.wikipedia.org/wiki/Functional%20response | A functional response in ecology is the intake rate of a consumer as a function of food density (the amount of food available in a given ecotope). It is associated with the numerical response, which is the reproduction rate of a consumer as a function of food density. Following C. S. Holling, functional responses are generally classified into three types, which are called Holling's type I, II, and III.
Type I
The type I functional response assumes a linear increase in intake rate with food density, either for all food densities, or only for food densities up to a maximum, beyond which the intake rate is constant. The linear increase assumes that the time needed by the consumer to process a food item is negligible, or that consuming food does not interfere with searching for food. A functional response of type I is used in the Lotka–Volterra predator–prey model. It was the first kind of functional response described and is also the simplest of the three functional responses currently detailed.
Type II
The type II functional response is characterized by a decelerating intake rate, which follows from the assumption that the consumer is limited by its capacity to process food. Type II functional response is often modeled by a rectangular hyperbola, for instance as by Holling's disc equation, which assumes that processing of food and searching for food are mutually exclusive behaviors. The equation is
where f denotes intake rate and R denotes food (or resource) density. The rate at which the consumer encounters food items per unit of food density is called the attack rate, a. The average time spent on processing a food item is called the handling time, h. Similar equations are the Monod equation for the growth of microorganisms and the Michaelis–Menten equation for the rate of enzymatic reactions.
In an example with wolves and caribou, as the number of caribou increases while holding wolves constant, the number of caribou kills increases and then levels off. This |
https://en.wikipedia.org/wiki/Pararectal%20lymph%20nodes | The pararectal lymph nodes are lymph nodes that are in contact with the muscular coat of the rectum.
Structure
The pararectal lymph nodes are located on the left and right of the rectum. Their efferent lymph ducts pass to the pre-aortic lymph nodes.
Function
The pararectal lymph nodes drain the descending iliac and sigmoid parts of the large intestine, and the upper part of the rectum.
See also
Pectinate line |
https://en.wikipedia.org/wiki/Retroaortic%20lymph%20nodes | The retroaortic lymph nodes (or postaortic lymph nodes) are placed below the cisterna chyli, on the bodies of the third and fourth lumbar vertebrae.
They receive lymphatic trunks from the lateral and preaortic glands, while their efferents end in the cisterna chyli. |
https://en.wikipedia.org/wiki/Preaortic%20lymph%20nodes | The preaortic lymph nodes lie in front of the aorta, and may be divided into celiac lymph nodes, superior mesenteric lymph nodes, and inferior mesenteric lymph nodes groups, arranged around the origins of the corresponding arteries.
The celiac lymph nodes are grouped into three sets: the gastric, hepatic and splenic lymph nodes. These groups also form their own subgroups.
The superior mesenteric lymph nodes are grouped into three sets: the mesenteric, ileocolic and mesocolic lymph nodes.
The inferior mesenteric lymph nodes have a subgroup of pararectal lymph nodes.
The preaortic lymph nodes receive a few vessels from the lateral aortic lymph nodes, but their principal afferents are derived from the organs supplied by the three arteries with which they are associated–the celiac, superior and inferior mesenteric arteries.
Some of their efferents pass to the retroaortic lymph nodes, but the majority unite to form the intestinal lymph trunk, which enters the cisterna chyli.
Additional images |
https://en.wikipedia.org/wiki/Global%20Historical%20Climatology%20Network | The Global Historical Climatology Network (GHCN) is a data set of temperature, precipitation and pressure records managed by the National Climatic Data Center (NCDC), Arizona State University and the Carbon Dioxide Information Analysis Center.
The aggregate data are collected from many continuously reporting fixed stations at the Earth's surface. In 2012, there were 25,000 stations within 180 countries and territories. Some examples of monitoring variables are the total daily precipitation and maximum and minimum temperature. A caveat to this is 66% of the stations report only the daily precipitation.
The original idea for the application of the GHCN-M data was to provide climatic analysis for data sets that require daily monitoring. Its purpose is to create a global base-line data set that can be compiled from stations worldwide.
This work has often been used as a foundation for reconstructing past global temperatures, and was used in previous versions of two of the best-known reconstructions, that prepared by the NCDC, and that prepared by NASA as its Goddard Institute for Space Studies (GISS) temperature set. The average temperature record is 60 years long with ~1650 records greater than 100 years and ~220 greater than 150 years (based on GHCN v2 in 2006). The earliest data included in the database were collected in 1697.
History
The initial version of Global Historical Climatology Network was developed in the summer of 1992. This first version, known as Version 1 was a collaboration between research stations and data sets alike to the World Weather Records program and the World Monthly Surface Station Climatology from the National Center for Atmospheric Research. Within the stations, all of them have at least 10 years of data, 2/5 have more than 50 years of data, and 1/10 have 100 years of data. Version 1, or more commonly notated as V1 was the collection of monthly mean temperatures from 6,000 stations. There were, as of 2022, 3 subsequent versions of the |
https://en.wikipedia.org/wiki/Inferior%20mesenteric%20lymph%20nodes | The inferior mesenteric lymph nodes consist of:
(a) small glands on the branches of the left colic and sigmoid arteries
(b) a group in the sigmoid mesocolon, around the superior hemorrhoidal artery
(c) a pararectal group in contact with the muscular coat of the rectum
Structure
The inferior mesenteric lymph nodes are lymph nodes present throughout the hindgut.
Afferents
The inferior mesenteric lymph nodes drain structures related to the hindgut; they receive lymph from the descending colon, sigmoid colon, and proximal part of the rectum.
Efferents
They drain into the superior mesenteric lymph nodes and ultimately to the preaortic lymph nodes. Lymph nodes surrounding the inferior mesenteric artery drain directly into the preaortic nodes.
Clinical significance
Colorectal cancer may metastasise to the inferior mesenteric lymph nodes. For this reason, the inferior mesenteric artery may be removed in people with lymph node-positive cancer. This has been proposed since at least 1908, by surgeon William Ernest Miles.
Additional images |
https://en.wikipedia.org/wiki/Internal%20iliac%20lymph%20nodes | The internal iliac lymph nodes (or hypogastric) surround the internal iliac artery and its branches (the hypogastric vessels), and receive the lymphatics corresponding to the distribution of the branches of it, i. e., they receive lymphatics from all the pelvic viscera, from the deeper parts of the perineum, including the membranous and cavernous portions of the urethra, and from the buttock and back of the thigh. The internal iliac lymph nodes also drain the superior half of the rectum, above the pectinate line.
It does not receive lymph from the ovary or testis, which drain to the paraaortic lymph nodes.
Additional images
See also
External iliac lymph nodes
pararectal lymph nodes |
https://en.wikipedia.org/wiki/Dermatophyte%20test%20medium | Dermatophyte test medium (DTM) is a specialized agar used in medical mycology. It is based on Sabouraud's dextrose agar with added cycloheximide to inhibit saprotrophic growth, antibiotic to inhibit bacterial growth, and phenol red a pH indicator. The pH indicator is useful in distinguishing a dermatophyte fungus, which utilizes nitrogenous material for preferred metabolism, producing alkaline by-products, imparting a red color change to the medium. Typical saprotrophic fungi utilize carbohydrates in the medium producing acidic by-products and no red color change. |
https://en.wikipedia.org/wiki/Rhythm%20of%20the%20Rain | "Rhythm of the Rain" is a song performed by The Cascades, released in November 1962. It was written by Cascades band member John Claude Gummoe. On March 9, 1963, it rose to number 3 on the Billboard Hot 100, and spent two weeks at number 1 on Billboards Easy Listening chart. Billboard ranked the record as the number 4 song of 1963.
In March 1963, the song was a top 5 hit in the United Kingdom and, in May that same year, was a number 1 single in Ireland. In Australia it rose to number 2. In Canada, the song was on the CHUM Chart for a total of 12 weeks and reached number 1 in March 1963. In 1999 BMI listed the song as the 9th most performed song on radio/TV in the 20th century.
The Cascades' recording was used in the soundtrack of the 1979 film Quadrophenia, and included in its soundtrack album.
The song arrangement features distinctive use of a celesta played by arranger, Perry Botkin Jr.
The sound of rain and thunder are heard at the beginning and at the end of the song.
Theme
The lyrics are sung by a man whose lover has left him; the rain falling reminds him 'what a fool' he has been. He rhetorically asks the rain for answers, but ultimately he wishes it would 'go away' and let him cry alone.
Chart performance
Weekly charts
Year-end charts
Sylvie Vartan version (in French)
The song was adapted into French (under the title "En écoutant la pluie", meaning "Listening to the Rain") by Richard Anthony. It was recorded by Sylvie Vartan, who released it as a single in 1963.
According to the charts published by the U.S. magazine Billboard (in its "Hits of the World" section), the song "En écoutant la pluie" reached number one in France.
Track listings
7-inch single RCA Victor 45.277 (1963, France)
A. "En écoutant la pluie" (Rhythm of the Rain)
B. "Jamais" (Late Date Baby)
7-inch EP Sylvie à l'Olympia RCA 86.007 (1963, France)
A1. "En écoutant la pluie"
A2. "Jamais"
B1. "Avec moi"
B2. "Mon ami"
Charts
Other charting versions
Dutch teen idol Rob de Ni |
https://en.wikipedia.org/wiki/Dependency%20%28UML%29 | In the Unified Modeling Language (UML), a Dependency is a relationship that shows that an element, or set of elements, requires other model elements for their specification or implementation. The element is dependent upon the independent element, called the supplier. Two or more elements in this relationship are called tuples.
In the UML, this is indicated by a dashed line pointing from the dependent (or client) to the independent (or supplier) element. The arrow representing a Dependency specifies the direction of a relationship, not the direction of a process.
Standard predefined dependencies
UML - defined dependencies include :
«call2» UML2: The client (an operation) may call the supplier (an operation)
«create» UML2: The client (a classifier) may create instances of the supplier (a classifier)
«derive» UML2: The client (e.g., attribute value, link) may be computed from the supplier(s)
«instantiate» UML2: Operations of the client (a classifier) may create instances of the supplier (a classifier)
«permit» UML2: Obsolete
«realize» UML2: Obsolete
«refine» UML2: The client element(s) are at a "later" semantic level than the supplier(s)
«send» UML2: The client (an operation) sends the supplier (a signal)
«substitute» UML2: The client element can replace (under some circumstances) the supplier
«trace» UML2: The client elements "trace" to the suppliers. Typically used for levels of requirements
«use» UML2: The client element somehow "uses" the supplier
Differences with UML link
A UML link is run-time relationship between instances of classifiers, while a dependency is a model-time relationship between definitions.
A typical uni-directional link requires the one instance to know about, and thus depend, upon the other, but this is not required. A uni-directional link only requires the possibility of navigation not dependency.
Likewise, a bi-directional link requires that both inst |
https://en.wikipedia.org/wiki/Alexander%20Adams%20%28sailor%29 | Captain Alexander Adams (1780–1871) was a Scotsman who served in the British Royal Navy and then came to the Hawaiian islands and served in the navy of the Kingdom of Hawaii. Known to the Hawaiians as Alika Napunako Adams.
Britain
Adams was born December 27, 1780, in Arbroath, Angus, Scotland. He said his father was John Fyfe, who he said was the "Earl of Fyfe", born in Arbroath c. 1754. His mother was Jean Adams, born in Arbroath c. 1758.
Leaving Scotland in 1792, he worked 4 years aboard Zephyr belonging to Husson & Co. out of Newcastle upon Tyne, England. In 1796, he left Zephyr, and joined Calcutta out of Lancaster for two trips. He was drafted into naval service aboard after the Battle of Trafalgar in the Napoleonic Wars.
Hawaii
He arrived in Hawaii some time between 1809 and 1811 on the American trading ship Albatross from Boston.
He met King Kamehameha I and joined English sailor John Young, who had arrived in 1790, to command the navy of the Kingdom of Hawaii. He was awarded control of over in the Niu Valley, including control over the Kupapa Fishpond, which he later filled in for purposes of growing sweet potatoes. (east of Honolulu, coordinates ).
In April 1816 at Kawaihae Bay, Adams negotiated to buy a ship called Forester under Captain John Ebbetts which had been owned by American John Jacob Astor.
Prince Liholiho (soon to become King Kamehameha II) purchased the ship with sandalwood (Santalum ellipticum), and changed its name to Kaahumanu after his powerful stepmother Queen Kaahumanu. A condition of the deal was for Adams to take command of the ship. It was a small two-masted trading ship called a brig.
On March 7, 1817, the Kingdom of Hawaii sent Adams to China on his ship to sell sandalwood. To enter the harbor, the ship paid $3000 in port charges, making it not a financial success. Upon returning October 5, 1817, at Hilo and hearing of the amount Adams had to pay, King Kamehameha decided Hawaii should also generate revenue from port charges.
|
https://en.wikipedia.org/wiki/Qwerty%20effect | The QWERTY effect (or qwerty effect) emphasizes ways that modern keyboard layouts have influenced human language, naming preferences and behavior.
The Wubi effect references the same process of influence driven by autocomplete, Chinese input methods for computers (such as the Wubi method), and real time input suggestions from search engines based on current events. |
https://en.wikipedia.org/wiki/Cardinal%20ligament | The cardinal ligament (also transverse cervical ligament, lateral cervical ligament, or Mackenrodt's ligament) is a major ligament of the uterus formed as a thickening of connective tissue of the base of the broad ligament of the uterus. It extends laterally (on either side) from the cervix and vaginal fornix to attach onto the lateral wall of the pelvis. The female ureter, uterine artery, and inferior hypogastric (nervous) plexus course within the cardinal ligament. The cardinal ligament supports the uterus.
Structure
The cardinal ligament is a paired structure on the lateral side of the uterus. It originates from the lateral part of the cervix.
Attachments
It attaches the cervix to the lateral pelvic wall by its attachment to the obturator fascia of the obturator internus muscle. It attaches to the uterosacral ligament.
Relations
It is continuous externally with the fibrous tissue surrounding the pelvic blood vessels.
Function
The cardinal ligament supports the uterus, providing lateral stability to the cervix.
Clinical significance
The cardinal ligament may be affected in hysterectomy. Due to its proximity to the ureters, it can get damaged during ligation of the ligament. It is routinely cut during some uterine operations, although this can have side effects.
See also
Pelvic splanchnic nerves |
https://en.wikipedia.org/wiki/Fiocruz%20Genome%20Comparison%20Project | The Fiocruz Genome Comparison Project is a collaborative effort involving Brazil's Oswaldo Cruz Institute and IBM's World Community Grid, designed to produce a database comparing the genes from many genomes with each other using SSEARCH. The program SSEARCH performs a rigorous Smith–Waterman alignment between a protein sequence and another protein sequence, a protein database, a DNA or a DNA library.
The nature of the computation in the project allows it to easily take advantage of volunteer computing. This, along with the likely humanitarian benefits of the research, has led the World Community Grid (a volunteer computing grid that uses idle computer clock time) to run the Fiocruz project. All products are in the public domain by contract with WCG.
Description
The problem is that a very large information body (structural, functional, cross-references, etc.) is attached to protein database entries. Once entered the information is rarely updated or corrected. This annotation of predicted protein function is often incomplete, uses non-standard nomenclature or can be incorrect when cross referenced from previous sometimes incorrectly annotated sequences. Additionally, many proteins composed of several structural and/or functional domains are overlooked by automated systems. The comparative information today is huge when compared to the early days of genomics. A single error is compounded and then made complex.
The Genome Comparison Project performs a complete pairwise comparison between all predicted protein sequences, obtaining indices used (together with standardized Gene Ontology) as a reference repository for the annotator community. The project provides invaluable data sources for biologists. The sequence similarity comparison program used in the Genome Comparison Project is called SSEARCH. This program mathematically finds best local alignment between sequence pairs, and is a freely available implementation of the Smith–Waterman algorithm.
SSEARCH's use makes |
https://en.wikipedia.org/wiki/Dynamic%20carrier%20control | Dynamic carrier control (DCC) is a method of reducing power consumption in radio transmitters during periods of low audio activity or silence. It is a type of Modulation-Dependent Carrier Level control, or MDCL. All modern high-power (>50 kW) shortwave radio transmitters incorporate DCC of some kind, as well as some mediumwave (MW) transmitters.
DCC causes the carrier wave level to be automatically reduced when the audio is very weak or no audio is present. During periods of silence (no audio), the carrier power is reduced by 50%, so the 250 kW transmitter is putting out a carrier of 125 kW during audio pauses. This carrier power reduction saves electricity.
History
This amplitude modulation (and vestigial SSB modulation) energy-saving mode was devised in the late 1930s. The system was originally referred to as the Hapsburg Carrier System. DCC was not implemented in transmitter designs until the 1980s, because of some of the complexities of the control circuit.
DCC's development is linked to NATO nations trying to save energy as a result of the ripple effects of OPEC related oil supply crises.
DCC is still an option on all shortwave transmitters sold on the open market today, since it is almost universally mandated by the purchasers of shortwave transmitters.
Eastern European manufacturers of shortwave transmitters tended not to adopt DCC because Russia in particular had no energy crises, due to its abundant supply of oil.
MDCL methods
There are two types of Modulation-Dependent Carrier Level (MDCL) control methods: DCC, as discussed above, and Amplitude Modulation Companding (AMC), developed by the BBC. The AMC design achieves the opposite effect of the original DCC system: the carrier is at maximum when no audio is present, and is reduced by up to 75% when the audio is loudest. The system uses the carrier to quieten the channel when no audio is present, while still realizing power savings. Both DCC and AMC have been a staple in European MW broadcasting fo |
https://en.wikipedia.org/wiki/Cryptlib | cryptlib is an open-source cross-platform software security toolkit library. It is distributed under the Sleepycat License, a free software license compatible with the GNU General Public License. Alternatively, cryptlib is available under a proprietary license for those preferring to use it under proprietary terms.
Features
cryptlib is a security toolkit library that allows programmers to incorporate encryption and authentication services to software. It provides a high-level interface so strong security capabilities can be added to an application without needing to know many of the low-level details of encryption or authentication algorithms. It comes with an over 400 page programming manual.
At the highest level, cryptlib provides implementations of complete security services such as S/MIME and PGP/OpenPGP secure enveloping, SSL/TLS and SSH secure sessions, CA services such as CMP, SCEP, RTCS, and OCSP, and other security operations such as secure timestamping. Since cryptlib uses industry-standard X.509, S/MIME, PGP/OpenPGP, and SSH/SSL/TLS data formats, the resulting encrypted or signed data can be easily transported to other systems and processed there, and cryptlib itself runs on many operating systems—all Windows versions and most Unix/Linux systems. This allows email, files, and EDI transactions to be authenticated with digital signatures and encrypted in an industry-standard format.
cryptlib provides other capabilities including full X.509/PKIX certificate handling (all X.509 versions from X.509v1 to X.509v4) with support for SET, Microsoft AuthentiCode, Identrus, SigG, S/MIME, SSL, and Qualified certificates, PKCS #7 certificate chains, handling of certification requests and CRLs (certificate revocation lists) including automated checking of certificates against CRLs and online checking using RTCS and OCSP, and issuing and revoking certificates using CMP and SCEP. It also implements a full range of certification authority (CA) functions provides complet |
https://en.wikipedia.org/wiki/Systematic%20evolution%20of%20ligands%20by%20exponential%20enrichment | Systematic evolution of ligands by exponential enrichment (SELEX), also referred to as in vitro selection or in vitro evolution, is a combinatorial chemistry technique in molecular biology for producing oligonucleotides of either single-stranded DNA or RNA that specifically bind to a target ligand or ligands. These single-stranded DNA or RNA are commonly referred to as aptamers.
Although SELEX has emerged as the most commonly used name for the procedure, some researchers have referred to it as SAAB (selected and amplified binding site) and CASTing (cyclic amplification and selection of targets) SELEX was first introduced in 1990. In 2015, a special issue was published in the Journal of Molecular Evolution in the honor of quarter century of the discovery of SELEX.
The process begins with the synthesis of a very large oligonucleotide library, consisting of randomly generated sequences of fixed length flanked by constant 5' and 3' ends. The constant ends serve as primers, while a small number of random regions are expected to bind specifically to the chosen target. For a randomly generated region of length n, the number of possible sequences in the library using conventional DNA or RNA is 4n (n positions with four possibilities (A,T,C,G) at each position). The sequences in the library are exposed to the target ligand - which may be a protein or a small organic compound - and those that do not bind the target are removed, usually by affinity chromatography or target capture on paramagnetic beads. The bound sequences are eluted and amplified by PCR to prepare for subsequent rounds of selection in which the stringency of the elution conditions can be increased to identify the tightest-binding sequences. A caution to consider in this method is that the selection of extremely high, sub-nanomolar binding affinity entities may not in fact improve specificity for the target molecule. Off-target binding to related molecules could have significant clinical effects.
SELEX has |
https://en.wikipedia.org/wiki/Amanita%20verna | Amanita verna, commonly known as the fool's mushroom or the spring destroying angel (see destroying angel), is a deadly poisonous basidiomycete fungus, one of many in the genus Amanita. Occurring in Europe in spring, A. verna associates with various deciduous and coniferous trees. The caps, stipes and gills are all white in colour.
Taxonomy
Amanita verna was first mentioned in the scientific literature by French mycologist Jean Bulliard in 1780 as form vernus of Agaricus bulbosus. Bulliard warned that it could be easily confused with the edible field mushroom (Agaricus campestris), and that remedies for those who had eaten it included putting vitriolic ether in wine or crushed garlic in milk. The species name verna is derived from the Latin word for "spring". Three years later, Jean-Baptiste Lamarck gave it distinct species status in his Encyclopédie Méthodique, Botanique.
The fool's mushroom (Amanita verna), also known as the spring destroying angel or death angel, is a close relative of Amanita phalloides, the death cap, and a member of the mushroom genus Amanita. Amanita verna, like its close relative, belongs to the subfamily Phalloideae.
Description
The fool's mushroom is pure white, all the way to the gills and the stipe. This fungus, like many but not all amanitas, has a volva. The fool's mushroom's cap is wide, and is about the same height.
This mushroom's lamellae are free and white, and the volva is bag-like and large. Its annulus is white and membranous, and A. verna react yellow with 20% potassium hydroxide solution, unlike its relative Amanita phalloides var. alba while Amanita virosa gets an orange-yellow reaction. The mushroom's spores are smooth and elliptical.
Habitat and season
The fool's mushroom grows in European woodlands and hardwood forests in springtime as the fungus' Latin name (Amanita verna or spring destroying angel) suggests.
Unlike various closely related poisonous amanitas, this mushroom is not known to occur in North America. |
https://en.wikipedia.org/wiki/Unidirectional%20Lightweight%20Encapsulation | The Unidirectional Lightweight Encapsulation (ULE) is a Data link layer protocol for the transportation of network layer packets over MPEG transport streams.
Because of the very low protocol overhead, it is especially suited for IP over Satellite services (where every bit counts). Such a system is for example DVB-S. However, ULE can also be used in the context of DVB-C and DVB-T, theoretically in every system which is based on MPEG transport streams (e.g., ATSC).
ULE has been engineered by the IP over DVB (ipdvb) working group of the Internet Engineering Task Force (IETF) and has been standardized in RFC 4326.
Another encapsulation method is Multiprotocol Encapsulation (MPE) which was developed and standardized by the DVB project.
See also
MPEG-2
Generic Stream Encapsulation (GSE)
Multiprotocol Encapsulation (MPE)
Datacasting
Internet Protocol Datacasting (IPDC) for DVB-H
UDcast
Interactive television
Implementations
Software:
Linux Kernel,
ulenet for Windows XP,
The ipdvb Working Group maintains a list of ULE implementations. |
https://en.wikipedia.org/wiki/Differentiated%20security | Differentiated security is a form of computer security that deploys a range of different security policies and mechanisms according to the identity and context of a user or transaction.
This makes it much more difficult to scale or replicate attacks, since each cluster/individual has a different security profile and there should be no common weaknesses.
One way of achieving this is by subdividing the population into small differentiated clusters. At the extreme, each individual belongs to a different class.
See also
Differentiated service (design pattern)
Separation of protection and security
External links
Differentiated security in wireless networks Andreas Johnsson, 2002.
Computer security procedures |
https://en.wikipedia.org/wiki/Lindstr%C3%B6m%20quantifier | In mathematical logic, a Lindström quantifier is a generalized polyadic quantifier. Lindström quantifiers generalize first-order quantifiers, such as the existential quantifier, the universal quantifier, and the counting quantifiers. They were introduced by Per Lindström in 1966. They were later studied for their applications in logic in computer science and database query languages.
Generalization of first-order quantifiers
In order to facilitate discussion, some notational conventions need explaining. The expression
for A an L-structure (or L-model) in a language L, φ an L-formula, and a tuple of elements of the domain dom(A) of A. In other words, denotes a (monadic) property defined on dom(A). In general, where x is replaced by an n-tuple of free variables, denotes an n-ary relation defined on dom(A). Each quantifier is relativized to a structure, since each quantifier is viewed as a family of relations (between relations) on that structure. For a concrete example, take the universal and existential quantifiers ∀ and ∃, respectively. Their truth conditions can be specified as
where is the singleton whose sole member is dom(A), and is the set of all non-empty subsets of dom(A) (i.e. the power set of dom(A) minus the empty set). In other words, each quantifier is a family of properties on dom(A), so each is called a monadic quantifier. Any quantifier defined as an n > 0-ary relation between properties on dom(A) is called monadic. Lindström introduced polyadic ones that are n > 0-ary relations between relations on domains of structures.
Before we go on to Lindström's generalization, notice that any family of properties on dom(A) can be regarded as a monadic generalized quantifier. For example, the quantifier "there are exactly n things such that..." is a family of subsets of the domain of a structure, each of which has a cardinality of size n. Then, "there are exactly 2 things such that φ" is true in A iff the set of things that are such that φ is |
https://en.wikipedia.org/wiki/Paroophoron | The paroophoron (of Johnson) consists of a few scattered rudimentary tubules, best seen in a child, situated in the broad ligament between the epoöphoron and the uterus. Named for the Welsh anatomist David Johnson who originally described the structure at the University of Wales, Aberystwyth.
It is a remnant of the mesonephric tubules.
See also
Epoophoron |
https://en.wikipedia.org/wiki/Saprotrophic%20nutrition | Saprotrophic nutrition or lysotrophic nutrition is a process of chemoheterotrophic extracellular digestion involved in the processing of decayed (dead or waste) organic matter. It occurs in saprotrophs, and is most often associated with fungi (for example Mucor) and soil bacteria. Saprotrophic microscopic fungi are sometimes called saprobes. Saprotrophic plants or bacterial flora are called saprophytes (sapro- 'rotten material' + -phyte 'plant'), although it is now believed that all plants previously thought to be saprotrophic are in fact parasites of microscopic fungi or other plants. The process is most often facilitated through the active transport of such materials through endocytosis within the internal mycelium and its constituent hyphae.
Various word roots relating to decayed matter (detritus, sapro-), eating and nutrition (-vore, -phage), and plants or life forms (-phyte, -obe) produce various terms, such as detritivore, detritophage, saprotroph, saprophyte, saprophage, and saprobe; their meanings overlap, although technical distinctions (based on physiologic mechanisms) narrow the senses. For example, usage distinctions can be made based on macroscopic swallowing of detritus (as an earthworm does) versus microscopic lysis of detritus (as a mushroom does).
Process
As matter decomposes within a medium in which a saprotroph is residing, the saprotroph breaks such matter down into its composites.
Proteins are broken down into their amino acid composites through the breaking of peptide bonds by proteases.
Lipids are broken down into fatty acids and glycerol by lipases.
Starch is broken down into pieces of simple disaccharides by amylases.
Cellulose, a major portion of plant cells, and therefore a major constituent of decaying matter is broken down into glucose
These products are re-absorbed into the hypha through the cell wall by endocytosis and passed on throughout the mycelium complex. This facilitates the passage of such materials throughout the orga |
https://en.wikipedia.org/wiki/Computer-on-module | A computer-on-module (COM) is a type of single-board computer (SBC), a subtype of an embedded computer system. An extension of the concept of system on chip (SoC) and system in package (SiP), COM lies between a full-up computer and a microcontroller in nature. It is very similar to a system on module (SOM).
Design
COMs are complete embedded computers built on a single circuit board. The design is centered on a microprocessor with RAM, input/output controllers and all other features needed to be a functional computer on the one board. However, unlike a single-board computer, the COM usually lacks the standard connectors for any input/output peripherals to be attached directly to the board.
The module usually needs to be mounted on a carrier board (or "baseboard") which breaks the bus out to standard peripheral connectors. Some COMs also include peripheral connectors. Some can be used without a carrier.
A COM solution offers a dense package computer system for use in small or specialized applications requiring low power consumption or small physical size as is needed in embedded systems. As a COM is very compact and highly integrated, even complex CPUs, including multi-core technology, can be realized on a COM.
Some devices also incorporate field-programmable gate array (FPGA) components. FPGA-based functions can be added as IP cores to the COM itself or to the carrier card. Using FPGA IP cores adds to the modularity of a COM concept because I/O functions can be adapted to special needs without extensive rewiring on the printed circuit board.
A "computer-on-module" is also called a "system-on-module" (SOM).
History
The terms "Computer-on-Module" and "COM" were coined by VDC Research Group, Inc. (formerly Venture Development Corporation) to describe this class of embedded computer boards.
Dr. Gordon Kruberg, founder and CEO of Gumstix, is credited for creating the first COM, predating the next recognizable COM entries by almost 18 months.
Gumstix ARM Linux |
https://en.wikipedia.org/wiki/Relaxase | A relaxase is a single-strand DNA transesterase enzyme produced by some prokaryotes and viruses. Relaxases are responsible for site- and strand-specific nicks in unwound double-stranded DNA . Known relaxases belong to the rolling circle replication (RCR) initiator superfamily of enzymes and fall into two broad classes: replicative (Rep) and mobilization (Mob). The nicks produced by Rep relaxases initiate plasmid or virus RCR. Mob relaxases nick at origin of transfer (oriT) to initiate the process of DNA mobilization and transfer known as bacterial conjugation. Relaxases are so named because the single-stranded DNA nick that they catalyze lead to relaxation of helical tension.
Structure and mechanism
Known relaxases are metal ion dependent tyrosine transesterases. This means that they use a metal ion to aid the transfer of an ester bond from the DNA phosphodiester backbone to a catalytic tyrosine side chain, resulting in a long-lived covalent phosphotyrosine intermediate that essentially unified the nicked DNA strand and the enzyme as one molecule. Preliminary reports of relaxase inhibition by small molecules that mimic intermediates of this reaction were first reported in 2007. Such inhibition has implications related to preventing the propagation of antibiotic resistance in clinical settings.
The first relaxase x-ray crystal and NMR structures – of Rep relaxases from tomato yellow leaf curl virus (TYLCV) and adeno associated virus serotype 5 (AAV-5) – were solved in 2002. These revealed compact molecules composed of five-stranded, antiparallel beta sheet cores and peripheral alpha helices. A histidine-rich motif, previously identified by sequence conservation, was shown to be a metal ion binding site located on the beta sheet core, nearby the carboxy-terminal catalytic tyrosine residue. Later structures of the Mob relaxases TrwC from plasmid R388 and TraI from the F-plasmid confirmed that the Mob and Rep classes are evolutionarily related to one another through c |
https://en.wikipedia.org/wiki/Language%20equation | Language equations are mathematical statements that resemble numerical equations, but the variables assume values of formal languages rather than numbers. Instead of arithmetic operations in numerical equations, the variables are joined by language operations. Among the most common operations on two languages A and B are the set union A ∪ B, the set intersection A ∩ B, and the concatenation A⋅B. Finally, as an operation taking a single operand, the set A* denotes the Kleene star of the language A. Therefore language equations can be used to represent formal grammars, since the languages generated by the grammar must be the solution of a system of language equations.
Language equations and context-free grammars
Ginsburg and Rice
gave an alternative definition of context-free grammars by language equations. To every context-free grammar , is associated a system of equations in variables . Each variable is an unknown language over and is defined by the equation where , ..., are all productions for . Ginsburg and Rice used a fixed-point iteration argument to show that a solution always exists, and proved that i.e. any other solution must be a of this one.
For example, the grammar
corresponds to the equation system
which has as solution every superset of .
Language equations with added intersection analogously correspond to conjunctive grammars.
Language equations and finite automata
Brzozowski and Leiss studied left language equations where every concatenation is with a singleton constant language on the left, e.g. with variable , but not nor . Each equation is of the form with one variable on the right-hand side. Every nondeterministic finite automaton has such corresponding equation using left-concatenation and union, see Fig. 1. If intersection operation is allowed, equations correspond to alternating finite automata.
Baader and Narendran studied equations using left-concatenation and union and proved that their satisfiability problem is EXPTIME-c |
https://en.wikipedia.org/wiki/Astilbe%20Arendsii%20Group | Astilbe Arendsii Group (Astilbe × arendsii) is a cultivar group of complex hybrids with A. astilboides, A. chinensis, A. japonica, A. thunbergii and others. They are all perennial, herbaceous plants with flowers in various shades from white to purplish red.
Numerous cultivars exist, a majority of them produced by breeders in Germany and Holland. The name is derived from the surname of German horticulturist Georg Arends who was responsible for nearly all hybrid cultivars sold in North America.
Invalid names:
Astilbe ×arendsii Arends
Astilbe ×hybrida Ievinya & Lusinya |
https://en.wikipedia.org/wiki/Radeon%20HD%204000%20series | The Radeon R700 is the engineering codename for a graphics processing unit series developed by Advanced Micro Devices under the ATI brand name. The foundation chip, codenamed RV770, was announced and demonstrated on June 16, 2008 as part of the FireStream 9250 and Cinema 2.0 initiative launch media event, with official release of the Radeon HD 4800 series on June 25, 2008. Other variants include enthusiast-oriented RV790, mainstream product RV730, RV740 and entry-level RV710.
Its direct competition was nVidia's GeForce 200 series, which launched in the same month.
Architecture
This article is about all products under the brand "Radeon HD 4000 Series". All products implement TeraScale 1 microarchitecture.
Execution units
The RV770 extends the R600's unified shader architecture by increasing the stream processing unit count to 800 units (up from 320 units in the R600), which are grouped into 10 SIMD cores composed of 16 shader cores containing 4 FP MADD/DP ALUs and 1 MADD/transcendental ALU. The RV770 retains the R600's 4 Quad ROP cluster count, however, they are faster and now have dedicated hardware-based AA resolve in addition to the shader-based resolve of the R600 architecture. The RV770 also has 10 texture units, each of which can handle 4 addresses, 16 FP32 samples, and 4 FP32 filtering functions per clock cycle.
Memory and internal buses
RV770 features a 256-bit memory controller and is the first GPU to support GDDR5 memory, which runs at 900 MHz giving an effective transfer rate of 3.6 GHz and memory bandwidth of up to 115 GB/s. The internal ring bus from the R520 and R600 has been replaced by the combination of a crossbar and an internal hub.
Video acceleration
The SIP block UVD 2.0-2.2 implemented on the dies of all Radeon HD 4000 Series Desktop gpus, 48xx series is using uvd 2.0, 47xx-46xx-45xx-43xx series is using uvd 2.2.
Support is available for Microsoft Windows at release, for Linux with Catalyst 8.10. The free and open-source driver requires Li |
https://en.wikipedia.org/wiki/Gyne | The gyne (, from Greek γυνή, "woman") is the primary reproductive female caste of social insects (especially ants, wasps, and bees of order Hymenoptera, as well as termites). Gynes are those destined to become queens, whereas female workers are typically barren and cannot become queens. Having a queen is what makes a "queenright" hive, nest, or colony of eusocial insects. A colony with multiple queens is said to be a polygyne form, whereas one with only one is a monogyne form.
The red imported fire ant is known to have colonies in both polygyne and monogyne forms.
The small red ant, Leptothorax acervorum, has colonies that switch from monogyny to polygyny as a result of seasonal fluctuations.
The little fire ant Wasmannia auropunctata produces unique kinds of meiotic oocytes with a drastic reduction in recombination. These oocytes may either fuse together for gyne production (automictic parthenogenesis with central fusion) or be fertilized by male gametes for the production of workers.
In the wasp species Apoica flavissima queens display distinct morphological differences from the sterile worker class. In Ropalidia plebeiana, gynes do not stay in the nest after they emerge as adults, but may spend their winters in their maternal nests.
In species lacking morphological castes (i.e., where "workers" may not be sterile), the term "gyne" is usually reserved for those females whose entire life is spent as a reproductive or potential reproductive, as opposed to those who start life as a worker and subsequently attain reproductive status (often called a "replacement queen" or a "laying worker"). These can be seen in certain species of stingless bee like the Plebeia remota where both gynes and workers are capable of reproducing. In most species with annual colony cycles, only gynes can enter diapause and overwinter, while workers – both non-reproductive and reproductive – die off. In some groups, such as paper wasps, gynes join with other gynes at the time of nest |
https://en.wikipedia.org/wiki/Sacrovertebral%20angle | The sacrum is curved upon itself and placed very obliquely, its base projecting forward and forming the prominent sacrovertebral angle when articulated with the last lumbar vertebra.
It is also known as the "lumbosacral angle".
See also
Sacral promontory
Pelvic inlet |
https://en.wikipedia.org/wiki/Vlaams%20Instituut%20voor%20Biotechnologie | VIB is a research institute located in Flanders, Belgium. It was founded by the Flemish government in 1995, and became a full-fledged institute on 1 January 1996. The main objective of VIB is to strengthen the excellence of Flemish life sciences research and to turn the results into new economic growth. VIB spends almost 80% of its budget on research activities, while almost 12% is spent on technology transfer activities and stimulating the creation of new businesses, in addition VIB spends approximately 2% on socio-economic activities. VIB is member of EU-LIFE, an alliance of leading life sciences research centres in Europe.
The institute is led by Christine Durinx and Jérôme Van Biervliet. Ajit Shetty is chairman of the board of directors.
Goals
VIB's mission is to conduct frontline biomolecular research in life sciences for the benefit of scientific progress and the benefit of society. The strategic goals of the VIB are:
Strategic basic research
Technology transfer policy to transfer the inventions to consumers and patients
Scientific information for the general public
Research Centers
The VIB scientist works on the normal and abnormal or pathological processes occurring in a cell, an organ and an organism (humans, plants, micro organisms). Instead of relocating scientists to a new campus, the VIB researchers work in research departments on six Flemish campuses: Ghent University, KU Leuven, University of Antwerp, Vrije Universiteit Brussel, IMEC and Hasselt University.
Ghent University:
VIB Inflammation Research Center, UGent (Bart Lambrecht)
VIB Center for Plant Systems Biology, UGent (Dirk Inzé)
VIB Medical Biotechnology Center, UGent (Nico Callewaert)
Institute of Plant Biotechnology Outreach (IPBO), UGent (Marc Van Montagu)
KU Leuven:
VIB Center for Cancer Biology, KU Leuven (Scientific directors: Diether Lambrechts and Chris Marine)
VIB Center for Brain & Disease Research, KU Leuven (Scientific directors: Patrik Verstreken and Joris de Wit)
VIB Center |
https://en.wikipedia.org/wiki/Analytic%20space | An analytic space is a generalization of an analytic manifold that allows singularities. An analytic space is a space that is locally the same as an analytic variety. They are prominent in the study of several complex variables, but they also appear in other contexts.
Definition
Fix a field k with a valuation. Assume that the field is complete and not discrete with respect to this valuation. For example, this includes R and C with respect to their usual absolute values, as well as fields of Puiseux series with respect to their natural valuations.
Let U be an open subset of kn, and let f1, ..., fk be a collection of analytic functions on U. Denote by Z the common vanishing locus of f1, ..., fk, that is, let Z = { x | f1(x) = ... = fk(x) = 0 }. Z is an analytic variety.
Suppose that the structure sheaf of U is . Then Z has a structure sheaf , where is the ideal generated by f1, ..., fk. In other words, the structure sheaf of Z consists of all functions on U modulo the possible ways they can differ outside of Z.
An analytic space is a locally ringed space such that around every point x of X, there exists an open neighborhood U such that is isomorphic (as locally ringed spaces) to an analytic variety with its structure sheaf. Such an isomorphism is called a local model for X at x.
An analytic mapping or morphism of analytic spaces is a morphism of locally ringed spaces.
This definition is similar to the definition of a scheme. The only difference is that for a scheme, the local models are spectra of rings, whereas for an analytic space, the local models are analytic varieties. Because of this, the basic theories of analytic spaces and of schemes are very similar. Furthermore, analytic varieties have much simpler behavior than arbitrary commutative rings (for example, analytic varieties are defined over fields and are always finite-dimensional), so analytic spaces behave very similarly to finite-type schemes over a field.
Basic results
Every point |
https://en.wikipedia.org/wiki/MicroID | MicroID is a decentralized identity protocol. It was originally developed in 2005 by Jeremie Miller . A MicroID is a simple identifier comprising a hashed communication/identity URI (e.g. email, OpenID, and/or Yadis) and claimed URL. Together, the two elements create a hash that can be claimed by third-party services.
Ben Laurie demonstrated privacy problems with it in 2006
, as did Chris Erway in a Brown CS Technical Report in 2008
MicroID exchange
Here is an example of a MicroID hash, in pseudocode:
MicroID = sha1( sha1("mailto:user@example.com") + sha1("http://example.net/") );
The computed MicroID would then be placed on a web page to be claimed. A verifier, which would independently generate the MicroID, would then visit the page to see if the generated MicroID is the same as the MicroID on the page. If they are the same, a claim exists.
MicroID is based on a communication URI. Since both the MicroID provider and verifier can verify the communication URI, a proper MicroID implementation allows for trusted identity claims.
Security limitations
A MicroID is essentially a content URI signed with an email address or other attribution. Since the content URI is known for comparison purposes, a MicroID claim can be forged by anybody who knows the communication URI (e.g. email address) associated with the identity.
In particular, since a verifier must generate the MicroID in order to compare it, it follows that any party who is trusted to verify a user's MicroID must also be trusted to generate new authorship claims with it.
So if you can verify - you can forge.
Or in other words anyone (e.g. Alice) who can verify someone (e.g. Bob) their MicroID on a resource 'X' can also generate (spoof) a MicroID on any other document (e.g. Alice can generate a valid MicroID for a document Y, not equal to X, in Bob's name).
Assuming the identity is not known (e.g. 1) the publisher has chosen to remain anonymous and 2) denies others the ability to verify the Micro |
https://en.wikipedia.org/wiki/Amplidyne | An amplidyne is an obsolete electromechanical amplifier invented prior to World War II by Ernst Alexanderson. It consists of an electric motor driving a DC generator. The signal to be amplified is applied to the generator's field winding, and its output voltage is an amplified copy of the field current. The amplidyne was used in industry in high power servo and control systems, to amplify low power control signals to control powerful electric motors, for example. It is now mostly obsolete.
How an amplidyne works
An amplidyne comprises an electric motor which turns a generator on the same shaft. Unlike an ordinary motor-generator, the purpose of an amplidyne is not to generate a steady voltage but to generate a voltage proportional to an input current, to amplify the input in applications where high output power is required. The motor provides the power, turning the generator at a constant speed, and the signal to be amplified is applied to the generator's field winding. The higher the current applied to the winding, the stronger the magnetic field and thus the higher the output voltage of the generator. So the output voltage of the generator is an amplified copy of the current waveform applied to the field winding. In a typical generator, the load brushes are positioned perpendicular to the magnetic field flux. To convert a generator to an amplidyne, what would normally be the load brushes are connected together and the output is taken from another set of brushes that are parallel with the field. The perpendicular brushes are now called the 'quadrature' brushes. This simple change can increase the gain by a factor of 10,000 or more.
The amplidyne's frequency response is limited to low frequencies, it cannot even handle audio frequencies, so its use is limited to amplifying low frequency control signals in industrial processes.
Historically, amplidynes were one of the first amplifiers to generate very high power (tens of kilowatts), allowing precise feedback contr |
https://en.wikipedia.org/wiki/Simon%20Gosling | Simon "Goose" Gosling (born 9 April 1969) is a British designer and builder of special effects models and props. He is best known for his work on the Millennium Falcon cockpit for Star Wars: The Force Awakens in 2014. Also his work on commercials featuring stop-frame animation for Brisk, Apple Jacks and Chips Ahoy in America, and the Windy Miller adverts for Quaker Oats in Britain.
Gosling was born in Shrewsbury, Shropshire, a town he lived in until 1994.
Gosling has created props and models for films including The Brothers Grimm (2005), The Hitchhiker's Guide to the Galaxy (2005) and Stormbreaker (2006). In 2006, he supervised the building of Hex during the Sky One production of Hogfather, an adaptation of the Discworld novel by author Terry Pratchett.
On 22 April 2007, Hogfather won the BAFTA Television Craft Award for best special effects.
Gosling is also a musician, appearing on the soundtrack of the PlayStation videogame Croc 2.
Selected filmography
Star Wars: Episode I – The Phantom Menace (1997) Assistant prop maker
Les Visiteurs 2 (1998) Prosthetic technician
Band of Brothers (2000) Miniature model maker
Dinotopia (2002) Miniature Modeller
The Brothers Grimm (2003) Prop Modeller
The Hitch Hikers Guide To The Galaxy (2004) Prop Modeller
Stormbreaker (2005) Electronic prop Modeller
Terry Pratchett's Hogfather (2006) Prop Modeller
I Want Candy (2006) Prop Modeller
Babylon A.D. (2007) Prop Modeller
The Colour of Magic (2007) Supervising Prop Modeller
Dread (2009) Special effects technician
Gulliver's Travels (2010) Concept model maker
Captain America: The First Avenger (2011) Prop Modeller
Prometheus (2012) Prop Modeller
Snow White & the Huntsman (2012) Prop Modeller
Fast & Furious 6 (2013) Prop Modeller
Jupiter Ascending (2014) Prop Modeller
Kingsman: The Secret Service (2014) Prop Modeller
Pan (2015) Prop Modeller
Star Wars: The Force Awakens (2015) Senior Prop Modeller |
https://en.wikipedia.org/wiki/Half-metal | A half-metal is any substance that acts as a conductor to electrons of one spin orientation, but as an insulator or semiconductor to those of the opposite orientation. Although all half-metals are ferromagnetic (or ferrimagnetic), most ferromagnets are not half-metals. Many of the known examples of half-metals are oxides, sulfides, or Heusler alloys. Types of half-metallic compounds theoretically predicted so far include some Heusler alloys, such as Co2FeSi, NiMnSb, and PtMnSb; some Si-containing half–Heusler alloys with Curie temperatures over 600K, such as NiCrSi and PdCrSi; some transition-metal oxides, including rutile structured CrO2; some perovskites, such as LaMnO3 and SeMnO3; and a few more simply structured zincblende(ZB) compounds, including CrAs and superlattices. NiMnSb and CrO2 have been experimentally determined to be half-metals at very low temperatures.
In half-metals, the valence band for one spin orientation is partially filled while there is a gap in the density of states for the other spin orientation. This results in conducting behavior for only electrons in the first spin orientation. In some half-metals, the majority spin channel is the conducting one while in others the minority channel is.
Half-metals were first described in 1983, as an explanation for the electrical properties of manganese-based Heusler alloys.
Some notable half-metals are chromium(IV) oxide, magnetite, and lanthanum strontium manganite (LSMO), as well as chromium arsenide. Half-metals have attracted some interest for their potential use in spintronics. |
https://en.wikipedia.org/wiki/Even%E2%80%93odd%20rule | The even–odd rule is an algorithm implemented in vector-based graphic software, like the PostScript language and Scalable Vector Graphics (SVG), which determines how a graphical shape with more than one closed outline will be filled. Unlike the nonzero-rule algorithm, this algorithm will alternatively color and leave uncolored shapes defined by nested closed paths irrespective of their winding.
The SVG defines the even–odd rule by saying:
The rule can be seen in effect in many vector graphic programs (such as Freehand or Illustrator), where a crossing of an outline with itself causes shapes to fill in strange ways.
On a simple curve, the even–odd rule reduces to a decision algorithm for the point in polygon problem.
The SVG computer graphics vector standard may be configured to use the even–odd rule when drawing polygons, though it uses the non-zero rule by default.
Implementation
Below is a partial example implementation in Python:
def is_point_in_path(x: int, y: int, poly) -> bool:
# Determine if the point is on the path, corner, or boundary of the polygon
#
# Args:
# x -- The x coordinates of point.
# y -- The y coordinates of point.
# poly -- a list of tuples [(x, y), (x, y), ...]
#
# Returns:
# True if the point is in the path or is a corner or on the boundary
num = len(poly)
j = num - 1
c = False
for i in range(num):
if (x == poly[i][0]) and (y == poly[i][1]):
# point is a corner
return True
if ((poly[i][1] > y) != (poly[j][1] > y)):
slope = (x-poly[i][0])*(poly[j][1]-poly[i][1])-(poly[j][0]-poly[i][0])*(y-poly[i][1])
if slope == 0:
# point is on boundary
return True
if (slope < 0) != (poly[j][1] < poly[i][1]):
c = not c
j = i
return c
See also
Nonzero-rule
Jordan curve theorem
Complex polyg |
https://en.wikipedia.org/wiki/PIC%20%28markup%20language%29 | In computing, Pic is a domain-specific programming language by Brian Kernighan for specifying line diagrams.
The language contains predefined basic linear objects: line, move, arrow, and spline, the planar
objects box, circle, ellipse, arc, and definable composite elements.
Objects are placed with respect to other objects or absolute coordinates.
A liberal interpretation of the input invokes
default parameters when objects are incompletely specified.
An interpreter translates this description into
concrete drawing commands in a variety of possible output formats.
Pic is a procedural programming language, with variable assignment, macros, conditionals, and looping. The language is an example of a little language originally intended for the comfort of non-programmers in the Unix environment (Bentley 1988).
History
Pic was implemented using Yacc compiler-compiler.
Implementations
Pic was first implemented as a preprocessor in the troff document processing system but is now often used with LaTeX. The pic preprocessor filters a source document, replacing diagram descriptions by drawing commands in a specified format, and passing the rest of the document through without change. Alternatively, diagram source is passed through the preprocessor to produce a file for insertion into the
document source.
A version of pic is included in groff, the GNU version of troff. GNU pic can also act as a preprocessor for TeX documents, emitting its own tpic DVI specials, which aren't as widely supported as those of other TeX graphic facilities. Arbitrary diagram text can be included for formatting by the word processor to which the pic output is directed, and arbitrary graphic processor commands can also be included.
DPIC
Dwight Aplevich's implementation, DPIC, can also generate pdf, postscript, svg, and other images by itself, as well as act as a preprocessor producing several LaTeX-compatible output formats. The three principal sources of pic processors are GNU pic, found on m |
https://en.wikipedia.org/wiki/Ecosystem%20model | An ecosystem model is an abstract, usually mathematical, representation of an ecological system (ranging in scale from an individual population, to an ecological community, or even an entire biome), which is studied to better understand the real system.
Using data gathered from the field, ecological relationships—such as the relation of sunlight and water availability to photosynthetic rate, or that between predator and prey populations—are derived, and these are combined to form ecosystem models. These model systems are then studied in order to make predictions about the dynamics of the real system. Often, the study of inaccuracies in the model (when compared to empirical observations) will lead to the generation of hypotheses about possible ecological relations that are not yet known or well understood. Models enable researchers to simulate large-scale experiments that would be too costly or unethical to perform on a real ecosystem. They also enable the simulation of ecological processes over very long periods of time (i.e. simulating a process that takes centuries in reality, can be done in a matter of minutes in a computer model).
Ecosystem models have applications in a wide variety of disciplines, such as natural resource management, ecotoxicology and environmental health, agriculture, and wildlife conservation. Ecological modelling has even been applied to archaeology with varying degrees of success, for example, combining with archaeological models to explain the diversity and mobility of stone tools.
Types of models
There are two major types of ecological models, which are generally applied to different types of problems: (1) analytic models and (2) simulation / computational models. Analytic models are typically relatively simple (often linear) systems, that can be accurately described by a set of mathematical equations whose behavior is well-known. Simulation models on the other hand, use numerical techniques to solve problems for which analytic solutio |
https://en.wikipedia.org/wiki/Protofection | Protofection is a protein-mediated transfection of foreign mitochondrial DNA (mtDNA) into the mitochondria of cells in a tissue to supplement or replace the native mitochondrial DNA already present. The complete mtDNA genome or just fragments of mtDNA generated by polymerase chain reaction can be transferred into the target mitochondria through the technique.
Scientists have hypothesized for the last couple of decades that protofection can be beneficial for patients with mitochondrial diseases. This technique is a recent development and is continuously being improved. As mitochondrial DNA becomes progressively more damaged with age, this may provide a method of at least partially rejuvenating mitochondria in old tissue, restoring them to their original, youthful function.
Method
Protofection is a developing technique and is continuously being improved. A specific protein transduction system has been created that is complexed with mtDNA, which enables the mtDNA to move across the targeted cell's membrane and specifically target mitochondria. The transduction system used consists of a protein transduction domain, mitochondrial localization sequences, and mitochondrial transcription factor A. Each of these play a specific role in protofection:
A protein transduction domain is needed because they are small regions of proteins that can cross the cell membrane of cells, independently.
A specific mitochondrial localization sequences is used for protofection because it permits mtDNA to enter the mitochondria.
Mitochondrial transcription factor A is used because it unwinds the mtDNA that enters the mitochondria, which is critical for mtDNA replication.
This process can lead to an increase in the amount of mtDNA present in the mitochondria of the target cells.
The transduction system has been tweaked and modified, since the first use of protofection. To shorten the name of the complex, which was previously called PTD-MLS-TFAM complex, it is now named MTD-TFAM. MTD |
https://en.wikipedia.org/wiki/Hollywood%20%28graphics%20chip%29 | Hollywood is the name of the graphics processing unit (GPU) used in Nintendo's Wii video game console. It was designed by ATI (now AMD), and is manufactured using the same 90 nm or 65 nm (depending on the hardware revision) CMOS process as Broadway, the Wii's central processing unit. Very few official details about Hollywood were released to the public by Nintendo, ATI, or any other company involved in the Wii's development. The Hollywood GPU is reportedly based on the GameCube's Flipper GPU and is clocked 50% higher at 243 MHz, though these clock rates have never been officially confirmed.
Hollywood is a multi-chip module (MCM) package containing three dies under the cover in the Hollywood-A revision. The first of these three dies, codenamed Napa, controls the I/O functions, RAM access, the Audio DSP, and the actual GPU with its embedded DRAM, and measures 8 × 9 mm. The other, codenamed Vegas, holds 24 MB of "internal" 1T-SRAM and measures 13.5 × 7 mm. A third, tiny die contains EEPROM. The Hollywood-1 revision was fabricated on a 65 nm node and merges Napa and Vegas into a single die, resulting in a two-die MCM.
Hardware capabilities
243 MHz graphics chip
3MB embedded GPU memory (eDRAM)
2MB dedicated to Z-buffer and framebuffer
1MB texture cache
24MB 1T-SRAM @ 486 MHz (3.9GB/s) directly accessible for textures and other video data
Fixed function pipeline (no support for programmable vertex or pixel shaders in hardware)
Texture Environment Unit (TEV) - capable of combining up to 8 textures in up to 16 stages or "passes"
~30GB/s internal bandwidth^
~18 million polygons/second^
972Mpixels/sec peak pixel fillrate
Note: ^ denotes speculation: using confirmed AMD GameCube data x 1.5, a crude but likely accurate way of calculating the Wii's results based on clock speeds and identical architecture.
Texture Environment Unit
The Texture Environment Unit (TEV) is a unique piece of hardware exclusive to the GameCube and Wii. The Wii inherited the TEV from Flip |
https://en.wikipedia.org/wiki/Framework-specific%20modeling%20language | A framework-specific modeling language (FSML) is a kind of domain-specific modeling language which is designed for an object-oriented application framework.
FSMLs define framework-provided abstractions as FSML concepts and decompose the abstractions into features. The features represent implementation steps or choices.
A FSML concept can be configured by selecting features and providing values for features.
Such a concept configuration represents how the concept should be implemented in the code. In other words, concept configuration describes how the framework should be completed in order to create the implementation of the concept.
Applications
FSMLs are used in model-driven development for creating models or specifications of software to be built.
FSMLs enable
the creation of the models from the framework completion code (that is, automated reverse engineering)
the creation of the framework completion code from the models (that is, automated forward engineering)
code verification through constraint checking on the model
automated round-trip engineering
Examples
Eclipse Workbench Part Interaction FSML
An example FSML for modeling Eclipse Parts (that is, editors and views) and Part Interactions (for example listens to parts, requires adapter, provides selection).
The prototype implementation supports automated round-trip engineering of Eclipse plug-ins that implement workbench parts and part interactions.
See also
General-purpose modeling (GPM)
Model-driven engineering (MDE)
Domain-specific language (DSL)
Model-driven architecture (MDA)
Meta-Object Facility (MOF) |
https://en.wikipedia.org/wiki/Molecular%20cytogenetics | Molecular cytogenetics combines two disciplines, molecular biology and cytogenetics, and involves the analysis of chromosome structure to help distinguish normal and cancer-causing cells. Human cytogenetics began in 1956 when it was discovered that normal human cells contain 46 chromosomes. However, the first microscopic observations of chromosomes were reported by Arnold, Flemming, and Hansemann in the late 1800s. Their work was ignored for decades until the actual chromosome number in humans was discovered as 46. In 1879, Arnold examined sarcoma and carcinoma cells having very large nuclei. Today, the study of molecular cytogenetics can be useful in diagnosing and treating various malignancies such as hematological malignancies, brain tumors, and other precursors of cancer. The field is overall focused on studying the evolution of chromosomes, more specifically the number, structure, function, and origin of chromosome abnormalities. It includes a series of techniques referred to as fluorescence in situ hybridization, or FISH, in which DNA probes are labeled with different colored fluorescent tags to visualize one or more specific regions of the genome. Introduced in the 1980s, FISH uses probes with complementary base sequences to locate the presence or absence of the specific DNA regions. FISH can either be performed as a direct approach to metaphase chromosomes or interphase nuclei. Alternatively, an indirect approach can be taken in which the entire genome can be assessed for copy number changes using virtual karyotyping. Virtual karyotypes are generated from arrays made of thousands to millions of probes, and computational tools are used to recreate the genome in silico.
Common techniques
Fluorescence in situ hybridization (FISH)
Fluorescence In Situ Hybridization maps out single copy or repetitive DNA sequences through localization labeling of specific nucleic acids. The technique utilizes different DNA probes labeled with fluorescent tags that bind to one |
https://en.wikipedia.org/wiki/AY-3-8500 | The AY-3-8500 "Ball & Paddle" integrated circuit was the first in a series of ICs from General Instrument designed for the consumer video game market. These chips were designed to output video to an RF modulator, which would then display the game on a domestic television set. The AY-3-8500 contained six selectable games — tennis (a.k.a. Pong), hockey (or soccer), squash, practice, and two shooting games. The AY-3-8500 was the 625-line PAL version and the AY-3-8500-1 was the 525-line NTSC version. It was introduced in 1976, Coleco becoming the first customer having been introduced to the IC development by Ralph H. Baer. A minimum number of external components were needed to build a complete system.
The AY-3-8500 was the first version. It played seven Pong variations. The video was in black-and-white, although it was possible to colorize the game by using an additional chip, such as the AY-3-8515.
Games
Six selectable games for one or two players were included:
In addition, a seventh undocumented game could be played when none of the previous six was selected: Handicap, a hockey variant where the player on the right has a third paddle. This game was implemented on very few systems.
Usage
The AY-3-8500 was designed to be powered by six 1.5 V cells (9 V). Its specified operation is at 6-7 V and a maximum of 12 V instead of the 5 V standard for logic. The nominal clock was 2.0 MHz, yielding a 500 ns pixel width. One way to generate such a clock is to divide a 14.31818 MHz 4 × colorburst clock by 7, producing 2.04545 MHz. It featured independent video outputs for left player, right player, ball, and playground+counter, that were summed using resistors, allowing designers to use a different luminance for each one. It was housed in a standard 28-pin DIP.
Applications
Some of the dedicated consoles employing the AY-3-8500 (there are at least two hundred different consoles using this chip):
Sears Hockey Pong
Coleco Telstar series (Coleco Telstar, Coleco Telstar Clas |
https://en.wikipedia.org/wiki/Preservation%20breeding | Preservation breeding is an attempt by many plant and animal breeders to preserve bloodlines of species, either of a rare breed, or of rare pedigrees within a breed.
Purpose
Preservation breeding can have several purposes:
Protection of genetic diversity within a species or a breed;
Preservation of valuable genetic traits that may not be popular or in fashion in the present, but may be of great value in the future;
Population or re-population of an area where a species previously existed;
Support of a wild population that is defective or infected, by breeding healthy individuals and releasing them into the population in order to strengthen the overall health of the population.
Mechanism
Preservation breeding can take the following forms:
Selective breeding of rare breeds and rare pedigrees, particularly monitoring breeding genetics in small populations to ensure diversity is maintained as much as possible;
Rare breeds that suffer life-threatening genetic deficiencies can be intentionally cross-bred with other breeds that have the critical gene, in order to preserve the rare breed into the future;
History
The term preservation breeding was first used by notable American Kennel Club Judges Douglas Johnson and Bill Shelton in breeder seminars for dog breeders in the early 2000s. The preservation of dog breeds and the conservancy of canine genetics started gaining more traction in the mid-2010s.
See also
Breeding back
Conservation genetics |
https://en.wikipedia.org/wiki/West%20number | The West number is an empirical parameter used to characterize the performance of Stirling engines and other Stirling systems. It is very similar to the Beale number where a larger number indicates higher performance; however, the West number includes temperature compensation. The West number is often used to approximate of the power output of a Stirling engine. The average value is (0.25) for a wide variety of engines, although it may range up to (0.35), particularly for engines operating with a high temperature differential.
The West number may be defined as:
where:
Wn is the West number
Wo is the power output of the engine (watts)
P is the mean average gas pressure (Pa) or (MPa, if volume is in cm3)
V is swept volume of the expansion space (m3, or cm³, if pressure is in MPa)
f is the engine cycle frequency (Hz)
TH is the absolute temperature of the expansion space or heater (kelvins)
TK is the absolute temperature of the compression space or cooler (kelvins)
Bn is the Beale number for an engine operating between temperatures TH and TK
When the Beale number is known, but the West number is not known, it is possible to calculate it. First calculate the West number at the temperatures TH and TK for which the Beale number is known, and then use the resulting West number to calculate output power for other temperatures.
To estimate the power output of a new engine design, nominal values are assumed for the West number, pressure, swept volume and frequency, and the power is calculated as follows:
For example, with an absolute temperature ratio of 2, the portion of the equation representing temperature correction equals 1/3. With a temperature ratio of 3, the temperature term is 1/2. This factor accounts for the difference between the West equation, and the Beale equation in which this temperature term is taken as a constant. Thus, the Beale number is typically in the range of 0.10 to 0.15, which is about 1/3 to 1/2 the value of the West number. |
https://en.wikipedia.org/wiki/Mediated%20VPN | A mediated VPN is a virtual private network topology where two or more participants connect to a central switchboard server managed typically by a third party in order to create a virtual private network between them, as distinct from a typical VPN arrangement whereby clients of an organisation connect to a VPN concentrator managed by the same organization.
Typically a switchboard server (referred to as a mediator) will manage several VPNs, identifying each individually by authentication credentials (such as username, network name and passwords). The mediator's role is to assign IP addresses to each participant in a VPN, and to encrypt data through the switchboard server in order to keep it secure from other participants in other VPNs.
See also
Virtual private network
Virtual Private LAN Service
Point-to-point (telecommunications) |
https://en.wikipedia.org/wiki/3DO%20Blaster | The 3DO Blaster is an add-on produced by Creative Labs and designed to allow compatible Windows-based PCs to play games for the 3DO Interactive Multiplayer. It is a full-sized ISA compatibility card, and unlike other such add-ons, it does not emulate a 3DO system, but rather the whole system's logic board is included, with the input (controllers) and output (video & audio) redirected to the PC.
The product was marketed as a single board for CD-ROM drive owners (but only drives with a Panasonic interface) or bundled with the necessary CD-ROM drive. The software drivers allowed for Windows (3.1) based gameplay, which featured real-time stretching of the game window and screenshot capturing. As graphics boards of the time (1994) were not up to par with the system's needs, a pass-through using a VGA feature connector link was used, thus reserving an area on screen to be used by the 3DO Blaster card's output. Thus, there was no impact on the CPU. As with the first 3DO system from Panasonic (REAL FZ-1) an FMV daughter-card enabling Video CD playback was planned, but since the 3DO Blaster failed to achieve momentum, it was never released. Saved games were stored in NVRAM on the card.
Bundle contents
The card was sold with the cables needed, a 3DO controller by Logitech, and two 3DO games on CD: Shock Wave from Electronic Arts and Gridders from Tetragon. Despite showing the 'long boxes' of the two games on the back of the packing box, they were included in jewel cases only. A third CD, containing demos of popular 3DO games was also included. Not included was software from Aldus; Aldus Photostyler SE and Aldus Gallery Effects Vol. 1, but pictures of both titles can be seen on the back of the 3DO Blaster packing box.
Hardware requirements
Intel or compatible PC with 80386 CPU and Microsoft Windows
Any of these Sound Blaster cards: Sound Blaster Pro, Sound Blaster 16 or Sound Blaster AWE32
A CD-ROM drive with a Panasonic interface
A free ISA slot
A VGA graphics card wi |
https://en.wikipedia.org/wiki/Uteroglobin | Uteroglobin, or blastokinin, also known as secretoglobin family 1A member 1 (SCGB1A1), is a protein that in humans is encoded by the SCGB1A1 gene.
SCGB1A1 is the founding member of the secretoglobin family of small, secreted, disulfide-bridged dimeric proteins found only in mammals. This antiparallel disulfide linked homodimeric protein is multifunctional and found in various tissues in various names such as: uteroglobin (UG, UGB), uteroglobin-like antigen (UGL), blastokinin, club-cell secretory protein (CCSP), Clara-cell 16 kD protein (17 in rat/mice), club-cell-specific 10 kD protein (CC10), human protein 1, urine protein 1 (UP-1), polychlorinated biphenyl-binding protein (PCB-BP), human club cell phospholipid-binding protein (hCCPBP), secretoglobin 1A member 1 (SCGB1A1).
This protein is specifically expressed in club cells in the lungs.
Function
The precise physiological role of uteroglobin is not yet known. Putative functions are:
Immunomodulation
Progesterone binding: weak in some animals, especially weak in humans. (Note: UGB is itself progesterone induced gene in the endometrium in Lagomorphs)
Inhibits phospholipase A2 in vitro
Binds phosphatidylcholine, phosphatidylinositol
Binds to fibronectin: The uteroglobulin knockout mice on the inbred C57Bl6 strain develop Goodpasture's syndrome like glomerulopathy due to fibronectin binding of IgA which might potentially be prevented by uteroglobin replacement. However contrary to the animal model claims, human genetic data might suggest that the effect may be indirect
Uteroglobin knockout mice on the inbred 129 strain appear to have healthy phenotype (no glomerulopathy development), but show physiological differences in their responses to respiratory challenges. The phenotype exhibited by these mice are; decreased bioaccumulation of biphenyls, susceptibility and increased IL-13, and IL-6 following hyperoxic challenge, and changes in the club cell morphology.
Target of polychlorinated biphenyl (pcb) bindin |
https://en.wikipedia.org/wiki/Bilinear%20program | In mathematics, a bilinear program is a nonlinear optimization problem whose objective or constraint functions are bilinear. An example is the pooling problem. |
https://en.wikipedia.org/wiki/Cholesterol%207%20alpha-hydroxylase | Cholesterol 7 alpha-hydroxylase also known as cholesterol 7-alpha-monooxygenase or cytochrome P450 7A1 (CYP7A1) is an enzyme that in humans is encoded by the gene which has an important role in cholesterol metabolism. It is a cytochrome P450 enzyme, which belongs to the oxidoreductase class, and converts cholesterol to 7-alpha-hydroxycholesterol, the first and rate limiting step in bile acid synthesis.
The inhibition of cholesterol 7-alpha-hydroxylase (CYP7A1) represses bile acid biosynthesis.
Evolution
Sequence comparisons indicated a huge similarity between cytochromes P450 identified in man and bacteria, and suggested that the superfamily cytochrome P450 first originated from a common ancestral gene some three billion years ago.
The superfamily cytochrome P450 was named in 1961, because of the 450-nm spectral peak pigment that cytochrome P450 has when reduced and bound to carbon monoxide. In the early 1960s, P450 was thought to be one enzyme, and by the mid 1960s it was associated with drug and steroid metabolism.
However, the membrane-associated and hydrophobic nature of the enzyme system impeded purification, and the number of proteins involved could not be accurately counted. Advances in mRNA purification in the early 1980s allowed to isolate the first cDNA encoding a complete cytochrome P450 (CYP) protein, and thereafter, results of many cloning studies have revealed a large number of different enzymes.
Advances in molecular biology and genomics facilitated the biochemical characterisation of individual P450 enzymes:
The cytochromes P450 act on many endogenous substrates, introducing oxidative, peroxidative, and reductive changes into small molecules of widely different chemical structures. Substrates identified to date include saturated and unsaturated fatty acids, eicosanoids, sterols and steroids, bile acids, vitamin D3 derivatives, retinoids, and uroporphyrinogens.
Many cytochrome P450 enzymes can metabolise various exogenous compounds including |
https://en.wikipedia.org/wiki/House%20call | A house call is medical consultation performed by a doctor or other healthcare professionals visiting the home of a patient or client, instead of the patient visiting the doctor's clinic or hospital. In some locations, families used to pay dues to a particular practice to underwrite house calls.
History
In the early 1930s, house calls by doctors were 40% of doctor-patient meetings. By 1980, it was only 0.6%. Reasons include increased specialization and technology. In the 1990s, team home care, including physician visits, was a small but growing field in health care, for frail older people with chronic illnesses.
The reasons for fewer house calls include concerns about providing low-overhead care in the home, time inefficiency, and inconvenience. Yet, there are more and more doctors who like the idea of no office overhead. Also, it can provide safe access to care by people who are ill. Today, house calls may be making a revival among the wealthy through concierge telemedicine and mobile apps.
Canada
In 2012 as part of its Action Plan for Healthcare the province of Ontario actively expanded funding for access to house calls with its primary focus being on seniors and those with physical limitations making it difficult for travel outside the home. Residents of Ontario with valid Ontario Health Insurance Plan cards are able to take advantage of the house call system, and arrange for appointments with physicians at their home. Currently, this service is only available in Toronto.
United States
In the United States, leadership such as George Washington were known to receive house calls. Upon his deathbed in 1799, President Washington received a house call prior to his passing. Presently, the United States' leadership retain a Physician to the President on staff.
Midwifery
The US rate of out-of-hospital birth has remained steady at 1% of all births since 1989, with data from 2007 showing that 27.3% of the home births since 1989 took place in a free-standing birt |
https://en.wikipedia.org/wiki/MAC%20filtering | In computer networking, MAC address filtering is a security access control method whereby the MAC address assigned to each network interface controller is used to determine access to the network.
MAC addresses are uniquely assigned to each card, so using MAC filtering on a network permits and denies network access to specific devices through the use of blacklists and whitelists. While the restriction of network access through the use of lists is straightforward, an individual person is not identified by a MAC address, rather a device only, so an authorized person will need to have a whitelist entry for each device that they would like to access the network.
While giving a network some additional protection, MAC filtering can be circumvented by using a packet analyzer to find a valid MAC and then using MAC spoofing to access the network using that address. MAC address filtering can be considered as security through obscurity because the effectiveness is based on "the secrecy of the implementation or its components".
Port security
Many devices that support MAC filtering do so on a device basis. Whitelisted MAC addresses are allowed through any port on the device and blacklisted MAC addresses are blocked on all ports. Other devices, such as Cisco Catalyst switches, support MAC filtering on a port-by-port basis. This is referred to as port security. Port security may be configured statically with a list, dynamically based on the first given number of addresses detected, or a combination of these two methods. When port security is configured, the default settings are to allow only one MAC address per port, and to shut down the port if the allowed number of addresses is exceeded.
See also
Access-control list
IP address blocking
Private VLAN |
https://en.wikipedia.org/wiki/Secretoglobin | Secretoglobins (SCGBs) are a family of small, alpha-helical, disulfide linked, dimeric proteins found only in mammals. This family was formerly known as the Uteroglobin/Clara cell 10-kDa family, after the two aliases of its founding member Uteroglobin.
Structure and function
The proteins are mostly alpha-helical, and the dimer is formed in an antiparallel way. The dimer interface features a cavity formed across the two monomers, which can accommodate small to medium sized ligands like steroids and phospholipids. The binding and release may be coupled with the redox state of the cystines, i.e. the presence of these disulfide bonds.
Many have regulatory functions.
Classification
The family was classified by sequence homology into 6 subfamilies in 2006. The human and mouse genomes only contain the first three families, per an 2011 update. Not every family is monophyletic.
Rat prostatein (rat prostatic steroid binding protein) is a three component, tetrameric protein complex built from three lipophilin-like genes in groups 2 and 3. Some sources describe it as the ortholog of lipophilin.
Extra subfamilies
Subfamilies 4 and 6 were originally described as found in human and mice, but they are now treated as duplicates of existing groups. Subfamily 5 is found in neither to begin with.
Subfamily 4 formerly included what is now known as group 1B and 2B as group 4A. Pairs of 1B/2B (ABP) genes are arranged head-to-head on the chromosome into "modules" that have been independently duplicated.
Subfamily 6 was supposed to include human and rat RYD5, now reassigned Scgb1c1.
Fel d 1 was supposed to be put into two subfamilies: chain 1 in subfamily 4, and chain 2 in subfamily 5. Although it is not mentioned in the 2011 update, InterPro matches suggest that CH1 is similar to 1B and CH2 is similar to 2B. Extra computational research confirms the similarity, invalidating subfamilies 4 and 5 fully. |
https://en.wikipedia.org/wiki/Ambulatory%20blood%20pressure | Ambulatory blood pressure monitoring (ABPM) measures blood pressure at regular intervals. It is believed to be able to reduce the white coat hypertension effect in which a patient's blood pressure is elevated during the examination process due to nervousness and anxiety caused by being in a clinical setting. ABPM can also detect the reverse condition, masked hypertension, where the patient has normal blood pressure during the examination but uncontrolled blood pressure outside the clinical setting, masking a high 24-hour average blood pressure. Out-of-office measurements are highly recommended as an adjunct to office measurements by almost all hypertension organizations.
Blood pressure variability
24-hour, non-invasive ambulatory blood pressure (BP) monitoring allows estimates of cardiac risk factors including excessive BP variability or patterns of circadian variability known to increase risks of a cardiovascular event.
Nocturnal hypertension
Ambulatory blood pressure monitoring allows blood pressure to be intermittently monitored during sleep and is useful to determine whether the patient is a "dipper" or "non-dipper"—that is to say, whether or not blood pressure falls at night compared to daytime values. A nighttime fall is normal and desirable. It correlates with relationship depth, and also other factors such as sleep quality, age, hypertensive status, marital status, and social network support. Absence of a nighttime dip is associated with poorer health outcomes; a 2011 study found increased mortality. Nocturnal hypertension is also associated with end organ damage, and is a much better indicator than the daytime blood pressure reading.
Target organ damage
Readings revealing possible hypertension-related end organ damage, such as left ventricular hypertrophy or narrowing of the retinal arteries, are more likely to be obtained through ambulatory blood pressure monitoring than through clinical blood pressure measurement. Isolated clinical BP measurements are |
https://en.wikipedia.org/wiki/Group%20of%20pictures | In video coding, a group of pictures, or GOP structure, specifies the order in which intra- and inter-frames are arranged. The GOP is a collection of successive pictures within a coded video stream. Each coded video stream consists of successive GOPs, from which the visible frames are generated. Encountering a new GOP in a compressed video stream means that the decoder doesn't need any previous frames in order to decode the next ones, and allows fast seeking through the video.
Description
A GOP can contain the following picture types:
I picture or I frame (intra coded picture, also called keyframe or i-frame) – a picture that is coded independently of all other pictures. Each GOP begins (in decoding order) with this type of picture.
P picture or P frame (predictive coded picture) – contains motion-compensated difference information relative to previously decoded pictures. In older designs such as MPEG-1, H.262/MPEG-2 and H.263, each P picture can only reference one picture, and that picture must precede the P picture in display order as well as in decoding order and must be an I or P picture. These constraints do not apply in the newer standards H.264/MPEG-4 AVC and HEVC.
B picture or B frame (bipredictive coded picture) – contains motion-compensated difference information relative to previously decoded pictures. In older designs such as MPEG-1 and H.262/MPEG-2, each B picture can only reference two pictures, the one which precedes the B picture in display order and the one which follows, and all referenced pictures must be I or P pictures. These constraints do not apply in newer standards H.264/MPEG-4 AVC and HEVC.
D picture or D frame (DC direct coded picture) – serves as a fast-access representation of a picture for loss robustness or fast-forward. D pictures are only used in MPEG-1 video.
An I frame indicates the beginning of a GOP. Afterwards several P and B frames follow. In older designs, the allowed ordering and referencing structure is relatively con |
https://en.wikipedia.org/wiki/Nuts%20%26%20Milk | is a puzzle-platform game developed and published by Japanese software developer Hudson Soft in 1983. The game was released for the FM-7, MSX, NEC PC-8801, NEC PC-6001, and later to the Famicom in Japan. Along with Lode Runner, it was the first third-party video game to be released on a Nintendo console.
Gameplay
Both versions of Nuts & Milk involve the player moving through various levels while collecting an assortment of fruit scattered throughout each of them. By gathering all the fruit on a particular screen, the player will gain access to a previously unopened house door containing Milk's fiancée, Yogurt. When the player makes contact with the female blob, they are advanced to the next level to start the process anew. Movement through these levels is accomplished by using the directional pad or keyboard to move Milk across the stage while avoiding pitfalls and other obstacles, most notably the character's rival, Nuts. If contact is made at any time during game play with Nuts or other harmful objects such as miniature blimps, the player will lose a life and have to restart the current level, with all fruit reset back to their initial positions. Once all three of Milk's lives are lost in this fashion, the game ends.
In the Famicom version, Milk can jump a short distance vertically or horizontally, allowing him to traverse pits or quickly gain access to an adjacent platform. If the player falls from too great a distance, Milk will become momentarily dazed and unable to move until the player joggles him awake with the jump button. Rope bridges are suspended in mid-air on most levels, and by using the directional pad, the player can climb them up or down as well as walk across them once they reach the top. In all, 50 individual levels exist on the Famicom version, and each one can be skipped freely by pressing the select button. Once a player has cycled through all fifty of them, he will return to the first level and restart the sequence until all of Milk's lives |
https://en.wikipedia.org/wiki/Hamming%20graph | Hamming graphs are a special class of graphs named after Richard Hamming and used in several branches of mathematics (graph theory) and computer science. Let be a set of elements and a positive integer. The Hamming graph has vertex set , the set of ordered -tuples of elements of , or sequences of length from . Two vertices are adjacent if they differ in precisely one coordinate; that is, if their Hamming distance is one. The Hamming graph is, equivalently, the Cartesian product of complete graphs .
In some cases, Hamming graphs may be considered more generally as the Cartesian products of complete graphs that may be of varying sizes. Unlike the Hamming graphs , the graphs in this more general class are not necessarily distance-regular, but they continue to be regular and vertex-transitive.
Special cases
, which is the generalized quadrangle
, which is the complete graph
, which is the lattice graph and also the rook's graph
, which is the singleton graph
, which is the hypercube graph . Hamiltonian paths in these graphs form Gray codes.
Because Cartesian products of graphs preserve the property of being a unit distance graph, the Hamming graphs and are all unit distance graphs.
Applications
The Hamming graphs are interesting in connection with error-correcting codes and association schemes, to name two areas. They have also been considered as a communications network topology in distributed computing.
Computational complexity
It is possible in linear time to test whether a graph is a Hamming graph, and in the case that it is, find a labeling of it with tuples that realizes it as a Hamming graph. |
https://en.wikipedia.org/wiki/Thermosynthesis | Thermosynthesis is a theoretical mechanism proposed by Anthonie Muller for biological use of the free energy in a temperature gradient to drive energetically uphill anabolic reactions. It makes use of this thermal gradient, or the dissipative structure of convection in this gradient, to drive a microscopic heat engine that performs condensation reactions. Thus negative entropy is generated. The components of the biological thermosynthesis machinery concern progenitors of today's ATP synthase, which functions according to the binding change mechanism, driven by chemiosmosis. Resembling primitive free energy generating physico-chemical processes based on temperature-dependent adsorption to inorganic materials such as clay, this simple type of energy conversion is proposed to have sustained the origin of life, including the emergence of the RNA World. For this RNA World it gives a model that describes the stepwise acquisition of the set of transfer RNAs that sustains the Genetic code. The phylogenetic tree of extant transfer RNAs is consistent with the idea.
Thermosynthesis may still occur in some terrestrial
and extraterrestrial environments. However, no organisms are known at present that use thermosynthesis as a source of energy, although it is possible that it might occur in extraterrestrial environments where no light is available, such as on the subsurface ocean that may exist on the moon Europa. Thermosynthesis also permits a simple model for the origin of photosynthesis. It has moreover been used to explain the origin of animals by symbiogenesis of benthic sessile thermosynthesizers at hydrothermal vents during the Snowball Earths of the Precambrian. Preliminary experiments have started to attempt to isolate thermosynthetic organisms.
Muller's Biothermosynthesis
A Dutch biochemist and physicist Anthonie Muller[1] wrote many papers on thermosynthesis since 1983.
He defined thermosynthesis as:
"Biological heat engines working on thermal cycling."
also as:
"Th |
https://en.wikipedia.org/wiki/Hemerocallis%20middendorffii | Hemerocallis middendorffii, known as Amur daylily, is a plant species in the subfamily Hemerocallidoideae of the family Asphodelaceae of the order Asparagales. It is native to the Russian Far East, northwest China, Korea, and Japan. It grows in meadows, mountain slopes, open woods, and scrub. It is cultivated in Asia for its edible flowers.
Description
Herbaceous perennial with linear arching leaves to . Flower scapes . Flowers 5–6, golden yellow to clear orange, large in a terminal head. Flowers in July for 2–3 weeks and often reblooms in September.
Four varieties are recognized:
H. middendorffii var. middendorfii: To . Flowers orange, odorless with elliptic to spathulate tepals. Bracts ovate, . The range of the species.
H. middendorffii var. esculenta (Koidz.) Ohwi: Japan
H. middendorffii var. exaltata (Stout) M.Hotta: Japan
H. middendorffii var. longibracteata Xiong: . Flowers yellow, fragrant with lanceolate tepals. Bracts ovate-lanceolate, . Endemic to China.
Cultivation
Easily cultivated on moist soil in a sunny site, but can tolerate poor soil and partial shade. Propagated by division and by seed. Takes 2–3 years to flower from seed.
Plants prefer a neutral to slightly acid soil and will suffer in very acid or alkaline soils. Generally free from pests and diseases. Hardy to USDA zone 4. |
https://en.wikipedia.org/wiki/Conservation%20in%20Papua%20New%20Guinea | Papua New Guinea together with the West Papua region of Indonesia (New Guinea) make up a major tropical wilderness area that still contains 5% of the original and untouched tropical high-biodiversity terrestrial ecosystems. PNG in itself contains over 5% of the world's biodiversity in less than 1% of the world's total land area. The flora of New Guinea is unique because it has two sources of origin; the Gondwana flora from the south and flora with Asian origin from the west. As a result, New Guinea shares major family and genera with Australia and the East Asia, but is rich in local endemic species. The endemicity is a result of mountainous isolation, topographic and soil habitat heterogeneity, high forest disturbance rates and abundant aseasonal rainfall year round. PNG boasts some 15–21,000 higher plants, 3,000 species of orchids, 800 species of coral, 600 species of fish, 250 species of mammals and 760 species of birds and 8 species of tree-kangaroos out of which 84 genera of animals are endemic. Ecosystems range from lowland forests to montane forests, alpine flora down to coastal areas which contains some of the most extensive pristine mangrove areas in the world. Much of this biodiversity has remained intact for thousands of years because the ruggedness of the terrain made the interior lands inaccessible; furthermore low population density and restrictions on the effectiveness of traditional tools, ensured that these biodiversity was never overexploited.
Biodiversity value
Even though this biodiversity is on just 1% of the world land mass, it has both global and local value. Most of the ecosystem service provided by the forests and oceans (e.g. water cycling, carbon cycling) is impartial to political boundaries. New Guinea was identified as the world's most floristically diverse island in the world, with 13,634 known species of vascular plants.
Within the country, about 79% of the PNG population depend on the biological resource to sustain their physical, s |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.