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https://en.wikipedia.org/wiki/Time%20deviation
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Time deviation (TDEV), also known as , is the time stability of phase x versus observation interval τ of the measured clock source. The time deviation thus forms a standard deviation type of measurement to indicate the time instability of the signal source. This is a scaled variant of frequency stability of Allan deviation. It is commonly defined from the modified Allan deviation, but other estimators may be used.
Time variance (TVAR) also known as is the time stability of phase versus observation interval tau. It is a scaled variant of modified Allan variance.
TDEV is a metric often used to determine an aspect of the quality of timing signals in telecommunication applications and is a statistical analysis of the phase stability of a signal over a given period. Measurements of a reference timing signal will refer to its TDEV and maximum time interval error (MTIE) values, comparing them to specified masks or goals.
Definition
The most common estimator uses the modified Allan variance
where . The 3 in the denominator normalizes TVAR to be equal to the classical variance if the deviations in x are random and uncorrelated (white-noise).
or TDEV, which is the square-root of TVAR, may be derived from MDEV modified Allan deviation
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https://en.wikipedia.org/wiki/Premature%20oxidation
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Premature oxidation, (sometimes shortened to premox, or POx) is a flaw that occurs in white wines, when the presumably ageworthy wine is expected to be in good condition yet is found to be oxidised and often undrinkable. In particular the affliction has received attention in connection to incidents of whites produced in Burgundy. The afflicted vintages are predominantly from the late 1990s, and in particular those of 96, 97 and 98, until 2002. There have also been reports of premature oxidation occurring in wines from Australia, Alsace, Germany, and Bordeaux.
Hypotheses
Clive Coates, MW has stated that "Poorly-performing corks are the main culprits behind prematurely aged white Burgundy", while Pierre Rovani of The Wine Advocate has stated the contrary, "corks are not the issue". Allen Meadows has speculated that "based on what we know today, the most likely source of the problem is cork-related, though it appears this has been exacerbated by generally lower levels of SO2", while Steve Tanzer believes it to be a combination of several factors that involve corks, global warming resulting in overripe fruit, excessive stirring of the lees, and insufficient use of sulfur dioxide. Roger Boulton, professor of UC Davis, agreed with the probability of multifactorial causality, stating, "there are likely to be both closure issues and wine chemistry issues, so looking for the [single] answer will be like missing the bus".
The French oenologists Denis Dubourdieu and Valérie Lavigne-Cruege launched a theory that with the recent trends of abstaining from the use of herbicides and letting grass grow freely in the vineyards of Burgundy, the grass competing with vines for water in conjunction with a warm vintage may cause the vines to endure extreme stress. As a result, grapes grown on highly stressed vines may have insufficient quantities of glutathione, a compound that functions as an essential antioxidant during the fermentation process.
According to Michel Bettane, Burgundy
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https://en.wikipedia.org/wiki/5-HT1%20receptor
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{{DISPLAYTITLE:5-HT1 receptor}}
The 5-HT1 receptors are a subfamily of the 5-HT serotonin receptors that bind to the endogenous neurotransmitter serotonin (also known as 5-hydroxytryptamine, or 5-HT). The 5-HT1 subfamily consists of five G protein-coupled receptors (GPCRs) that share 40% to 63% overall sequence homology, including 5-HT1A, 5-HT1B, 5-HT1D, 5-HT1E, and 5-HT1F. Receptors of the 5-HT1 type, specifically, the 5-HT1A and 5-HT1D receptor subtypes, are present on the cell bodies. Receptors of the 5-HT1 type, specifically, the 5-HT1B and 5-HT1D receptor subtypes, are also present on the nerve terminals. These receptors are broadly distributed throughout the brain and are recognized to play a significant part in regulating synaptic levels of 5-HT.
The receptor subfamily is coupled to Gi/Go and mediate inhibitory neurotransmission by inhibiting the function of adenylate cyclase and modulating downstream ionic effects. This R-coupling to Gi/Go proteins leads to a reduction in local concentrations of cAMP, proving that 5-HT1 are primarily inhibitory. There is no 5-HT1C receptor, as it was reclassified as the 5-HT2C receptor. For more information, please see the respective main articles of the individual subtypes:
See also
5-HT2 receptor
5-HT3 receptor
5-HT4 receptor
5-HT5 receptor
5-HT6 receptor
5-HT7 receptor
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https://en.wikipedia.org/wiki/Semelparity%20and%20iteroparity
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Semelparity and iteroparity are two contrasting reproductive strategies available to living organisms. A species is considered semelparous if it is characterized by a single reproductive episode before death, and iteroparous if it is characterized by multiple reproductive cycles over the course of its lifetime. Iteroparity can be further divided into continuous iteroparity (primates including humans and chimpanzees) and seasonal iteroparity (birds, dogs, etc.) Some botanists use the parallel terms monocarpy and polycarpy. (See also plietesials.)
In truly semelparous species, death after reproduction is part of an overall strategy that includes putting all available resources into maximizing reproduction, at the expense of future life (see § Trade-offs). In any iteroparous population there will be some individuals who die between their first and second reproductive episodes, but unless this is part of a syndrome of programmed death after reproduction, this would not be called semelparity.
This distinction is also related to the difference between annual and perennial plants. An annual is a plant that completes its life cycle in a single season, and is usually semelparous. Perennials live for more than one season and are usually (but not always) iteroparous.
Semelparity and iteroparity are not, strictly speaking, alternative strategies, but extremes along a continuum of possible modes of reproduction. Many organisms considered to be semelparous can, under certain conditions, separate their single bout of reproduction into two or more episodes.
Overview
Semelparity
The word semelparity was coined by evolutionary biologist Lamont Cole, and comes from the Latin semel 'once, a single time' and pario 'to beget'. This differs from iteroparity in that iteroparous species are able to have multiple reproductive cycles and therefore can mate more than once in their lifetime. Semelparity is also known as "big bang" reproduction, since the single reproductive event of sem
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https://en.wikipedia.org/wiki/Rotation%20formalisms%20in%20three%20dimensions
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In geometry, various formalisms exist to express a rotation in three dimensions as a mathematical transformation. In physics, this concept is applied to classical mechanics where rotational (or angular) kinematics is the science of quantitative description of a purely rotational motion. The orientation of an object at a given instant is described with the same tools, as it is defined as an imaginary rotation from a reference placement in space, rather than an actually observed rotation from a previous placement in space.
According to Euler's rotation theorem, the rotation of a rigid body (or three-dimensional coordinate system with a fixed origin) is described by a single rotation about some axis. Such a rotation may be uniquely described by a minimum of three real parameters. However, for various reasons, there are several ways to represent it. Many of these representations use more than the necessary minimum of three parameters, although each of them still has only three degrees of freedom.
An example where rotation representation is used is in computer vision, where an automated observer needs to track a target. Consider a rigid body, with three orthogonal unit vectors fixed to its body (representing the three axes of the object's local coordinate system). The basic problem is to specify the orientation of these three unit vectors, and hence the rigid body, with respect to the observer's coordinate system, regarded as a reference placement in space.
Rotations and motions
Rotation formalisms are focused on proper (orientation-preserving) motions of the Euclidean space with one fixed point, that a rotation refers to. Although physical motions with a fixed point are an important case (such as ones described in the center-of-mass frame, or motions of a joint), this approach creates a knowledge about all motions. Any proper motion of the Euclidean space decomposes to a rotation around the origin and a translation. Whichever the order of their composition will be,
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https://en.wikipedia.org/wiki/Darboux%20frame
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In the differential geometry of surfaces, a Darboux frame is a natural moving frame constructed on a surface. It is the analog of the Frenet–Serret frame as applied to surface geometry. A Darboux frame exists at any non-umbilic point of a surface embedded in Euclidean space. It is named after French mathematician Jean Gaston Darboux.
Darboux frame of an embedded curve
Let S be an oriented surface in three-dimensional Euclidean space E3. The construction of Darboux frames on S first considers frames moving along a curve in S, and then specializes when the curves move in the direction of the principal curvatures.
Definition
At each point of an oriented surface, one may attach a unit normal vector in a unique way, as soon as an orientation has been chosen for the normal at any particular fixed point. If is a curve in , parametrized by arc length, then the Darboux frame of is defined by
(the unit tangent)
(the unit normal)
(the tangent normal)
The triple defines a positively oriented orthonormal basis attached to each point of the curve: a natural moving frame along the embedded curve.
Geodesic curvature, normal curvature, and relative torsion
Note that a Darboux frame for a curve does not yield a natural moving frame on the surface, since it still depends on an initial choice of tangent vector. To obtain a moving frame on the surface, we first compare the Darboux frame of γ with its Frenet–Serret frame. Let
(the unit tangent, as above)
(the Frenet normal vector)
(the Frenet binormal vector).
Since the tangent vectors are the same in both cases, there is a unique angle α such that a rotation in the plane of N and B produces the pair t and u:
Taking a differential, and applying the Frenet–Serret formulas yields
where:
κg is the geodesic curvature of the curve,
κn is the normal curvature of the curve, and
τr is the relative torsion (also called geodesic torsion) of the curve.
Darboux frame on a surface
This section spec
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https://en.wikipedia.org/wiki/Oblique%20vein%20of%20the%20left%20atrium
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The oblique vein of the left atrium (oblique vein of Marshall) is a small vein which descends obliquely on the back of the left atrium and ends in the coronary sinus near its left extremity; it is continuous above with the ligament of the left vena cava (vestigial fold of Marshall), and the two structures form the remnant of the left Cuvierian duct. This obscure region of cardiac perfusion adjacent to the SA node rocks back and forth under systole and diastole thus further influencing cardiac autonomic innervation. Ablation of this channel seems reasonable to many observers.
Additional images
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https://en.wikipedia.org/wiki/Human-guided%20migration
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Human-guided migration or human-led migration is a method of restoring migratory routes of birds bred by humans for their reintroduction into the wild.
It is a technique especially used for endangered species in which the loss of individuals and territories has caused the disappearance of their migratory routes. To prevent their extinction, captive breeding has been needed, so their subsequent release into the wild requires teaching these routes to the juveniles.
Hand-reared juveniles have been imprinted on their adoptive parents, whom they follow. After a period of flight training and adaptation to the aircraft and its noise, the juveniles accompany their adoptive parents by flying to their wintering grounds.
This technique has been used in birds such as the northern bald ibis or the whooping crane, among other species.
See also
Cross-fostering
Fostering (falconry)
Hack (falconry)
Hand-rearing
Puppet-rearing
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https://en.wikipedia.org/wiki/PUBG%3A%20Battlegrounds
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PUBG: Battlegrounds (previously known as PlayerUnknown's Battlegrounds) is a battle royale game developed by PUBG Studios and published by Krafton. The game, which was inspired by the Japanese film Battle Royale (2000), is based on previous mods created by Brendan "PlayerUnknown" Greene for other games, and expanded into a standalone game under Greene's creative direction. It is the first game in the PUBG Universe series.
The game is played from either a third-person or first-person perspective. In the game, up to one hundred players parachute onto an island where they scavenge for weapons and equipment to kill other players while avoiding getting killed themselves. The available safe area of the game's map decreases in size over time, directing surviving players into an ever tightening space to force encounters. The last surviving player (or team) wins the round.
It was first released for Windows via Steam's early access beta program in March 2017, with a full release in December 2017. The game was also released by Microsoft Studios for the Xbox One via its Xbox Game Preview program that same month, and officially released in September 2018. PUBG Mobile, a free-to-play mobile game version for Android and iOS, was released in 2018, in addition to a port for the PlayStation 4. A version for the Stadia streaming platform was released in April 2020, with Xbox Series X/S and PlayStation 5 versions being released in November 2020. The game has been free-to-play for all platforms since January 12, 2022.
The game received positive reviews from critics, who found that while the game had some technical flaws, it presented new types of gameplay that could be easily approached by players of any skill level and was highly replayable. The game was credited with popularizing the battle royale genre, with a number of unofficial Chinese clones also being produced following its success. The game received several Game of the Year nominations and set seven Guinness World Records, a
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https://en.wikipedia.org/wiki/Translational%20glycobiology
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Translational glycobiology or applied glycobiology is the branch of glycobiology and glycochemistry that focuses on developing new pharmaceuticals through glycomics and glycoengineering. Although research in this field presents many difficulties, translational glycobiology presents applications with therapeutic glycoconjugates, with treating various bone diseases, and developing therapeutic cancer vaccines and other targeted therapies. Some mechanisms of action include using the glycan for drug targeting, engineering protein glycosylation for better efficacy, and glycans as drugs themselves.
Background
Glycans, or polysaccharides, are instrumental in many facets of biology, from decorations on cell membranes being involved in cell signaling and interaction to post-translational modifications on proteins warranting function. Yet even though sugars are the most abundant class of organic molecules found on earth, the study of their structure and function are not as well known as other biological molecules such as proteins and ribonucleic acids. This is partly due to the fact that glycans have no direct biosynthetic template in the genome, as opposed to protein, and thus have not been as effectively elucidated by the age of genomics. Furthermore, the polymeric nature of glycans presents a challenge to study, as there are plethora of combinations of linkages (unlike in DNA and protein) and many different types of monosaccharides and isomers.
Seeing as glycans play a key role in the biology of organisms, translational glycobiology thus aims to utilize them both as targets for drugs or as drugs themselves. New or improved glycan products arise as more is learned about the complex biological and chemical roles glycans play, paralleled by advancements in the carbohydrate synthesis toolbox.
Therapeutic uses
Since glycans play an important role in intercellular interactions and protein, they serve as viable targets for various therapeutic interactions. Multiple current th
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https://en.wikipedia.org/wiki/Aurora%20%28supercomputer%29
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Aurora is a planned supercomputer, originally contracted to be completed by 2018 but through a series of delays at the prime contractor, Intel Corporation, now planned to be completed in 2023. It was originally planned be the worlds’ fastest supercomputer with over 2 exaflops, however a series of delays have cast that into doubt. It is sponsored by the United States Department of Energy (DOE) and designed by Intel and Cray for the Argonne National Laboratory. It will have 2 exaFLOPS in computing power which is approximately a quintillion (260 or 1018) calculations per second and will have an expected cost of US$500 million. It will follow Frontier, which was the world's first exascale supercomputer in 2022 and as of June 2023 the world's fastest. Olivier Franza is the chief architect and principal investigator of this design.
History
In 2013 DOE presented their exascale vision of one exaFLOP at 20 MW by 2020. Aurora was first announced in 2015 and to be finished in 2018. It was expected to have a speed of 180 petaFLOPS which would be around the speed of Summit. Aurora was meant to be the most powerful supercomputer at the time of its launch and to be built by Cray with Intel processors. Later, in 2017, Intel announced that Aurora would be delayed to 2021 but scaled up to 1 exaFLOP. In March 2019, DOE said that it would build the first supercomputer with a performance of one exaFLOP in the United States in 2021. In October 2020, DOE said that Aurora would be delayed again for a further 6 months and would no longer be the first exascale computer in the US. In late October 2021 Intel announced Aurora would now exceed 2 exaFLOPS in peak double-precision compute. The system has been fully installed.
Planned usage
Planned functions include research on nuclear fusion, low carbon technologies, subatomic particles, cancer and cosmology. It will also develop new materials that will be useful for batteries and more efficient solar cells. It is to be available to the ge
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https://en.wikipedia.org/wiki/207%20%28number%29
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207 (two hundred [and] seven) is the natural number following 206 and preceding 208. It is an odd composite number with a prime factorization of .
In Mathematics
207 is a Wedderburn-Etherington number. There are exactly 207 different matchstick graphs with eight edges. 207 is also a deficient number, as 207's proper divisors (divisors not including the number itself) only add up to 105:
See also
Peugeot 207
List of highways numbered 207
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https://en.wikipedia.org/wiki/Heberden%27s%20node
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Heberden's nodes are hard or bony swellings that can develop in the distal interphalangeal joints (DIP) (the joints closest to the end of the fingers and toes). They are a sign of osteoarthritis and are caused by formation of osteophytes (calcific spurs) of the articular (joint) cartilage in response to repeated trauma at the joint.
Heberden's nodes typically develop in middle age, beginning either with a chronic swelling of the affected joints or the sudden painful onset of redness, numbness, and loss of manual dexterity. This initial inflammation and pain eventually subsides, and the patient is left with a permanent bony outgrowth that often skews the fingertip sideways. Bouchard's nodes may also be present; these are similar bony growths in the proximal interphalangeal (PIP) joints (middle joints of the fingers), and are also associated with osteoarthritis.
Heberden's nodes are more common in women than in men, and there seems to be a genetic component involved in predisposition to the condition.
They are named after William Heberden (1710–1801).
See also
Bouchard's nodes Also present in martial artists, in particular judoka and Brazilian jiu-jitsu practitioners.
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https://en.wikipedia.org/wiki/Internet%20Storage%20Name%20Service
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In computing, the proposed Internet Storage Name Service (iSNS) protocol allows automated discovery, management and configuration of iSCSI and Fibre Channel devices (using iFCP gateways) on a TCP/IP network.
Features
iSNS provides management services similar to those found in Fibre Channel networks, allowing a standard IP network to operate in much the same way that a Fibre Channel storage area network does. Because iSNS is able to emulate Fibre Channel fabric services and manage both iSCSI and Fibre Channel devices, an iSNS server can be used as a consolidated configuration point for an entire storage network. However, the use of iSNS is optional for iSCSI while it is required for iFCP. Additionally, an iSNS implementation is not required by the standard to provide support for both of these protocols.
Components
The iSNS standard defines four components:
The iSNS Protocol iSNSP is a protocol that specifies how iSNS clients and servers communicate. It is intended to be used by various platforms, including switches and targets as well as server hosts.
iSNS Clients iSNS clients are part of iSNSP aware storage devices. iSNS clients initiate transactions with iSNS servers using the iSNSP, register device attribute information in a common Discovery Domain (DD), download information about other registered clients and receive asynchronous notification of events that occur in their DD(s).
iSNS Servers iSNS servers respond to iSNS protocol queries and requests made by iSNS clients using the iSNSP. iSNS servers initiate iSNSP State Change Notifications and store properly authenticated information submitted by a registration request in an iSNS database.
iSNS Databases iSNS databases are the information repositories for iSNS server(s). They maintain information about iSNS client attributes; while implementations will vary, a directory-enabled implementation of iSNS, for example, might store client attributes in an LDAP directory.
Services
An iSNS implementation
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https://en.wikipedia.org/wiki/The%20Hermit%20%28tarot%20card%29
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The Hermit (IX) is the ninth trump or Major Arcana card in most traditional tarot decks. It is used in game playing as well as in divination.
Description
The Rider–Waite version of the card shows an old man, standing on a mountain peak, carrying a staff in one hand and a lit lantern containing a six-pointed star in the other. In the background is a mountain range.
According to Eden Gray, his lantern is the Lamp of Truth, used to guide the unknowing, his patriarch's staff helps him navigate narrow paths as he seeks enlightenment and his cloak is a form of discretion.
Interpretation
According to A.E. Waite's 1910 book Pictorial Key to the Tarot, the Hermit card carries several divinatory associations:
9. THE HERMIT. Prudence, circumspection; also and especially treason, dissimulation, roguery, corruption. Reversed: Concealment, disguise, policy fear, unreasoned caution.
The card is usually thought to connote aspects of healing/recovery, particularly the kind that happens over time. In that regard, The Hermit is sometimes considered the mature and wiser version of The Magician. As such, both cards represent the astrological sign of Virgo. The Hermit is the "withdrawal from events and relationship to introspect and gather strength". Seeking the inner voice or calling upon vision from within. A need of understanding and advice, or a wise person who will offer knowing guidance. A card of personal experience and thoughtful temperance.
Examples
In other media
A version of Pamela Colman Smith's Hermit designed by Barrington Colby is depicted on the inner jacket sleeve of Led Zeppelin IV.
In the X/1999 tarot version made by CLAMP, The Hermit is Satsuki Yatouji.
JoJo's Bizarre Adventure: Stardust Crusaders uses tarot cards to name character's Stands. Joseph Joestar has the Stand Hermit Purple, with abilities inspired by thoughtography.
The Binding of Isaac utilizes tarot cards as pickups that can be used to gain/activate in-game abilities, the Hermit warping the pla
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https://en.wikipedia.org/wiki/G%C3%B6del%20numbering%20for%20sequences
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In mathematics, a Gödel numbering for sequences provides an effective way to represent each finite sequence of natural numbers as a single natural number. While a set theoretical embedding is surely possible, the emphasis is on the effectiveness of the functions manipulating such representations of sequences: the operations on sequences (accessing individual members, concatenation) can be "implemented" using total recursive functions, and in fact by primitive recursive functions.
It is usually used to build sequential “data types” in arithmetic-based formalizations of some fundamental notions of mathematics. It is a specific case of the more general idea of Gödel numbering. For example, recursive function theory can be regarded as a formalization of the notion of an algorithm, and can be regarded as a programming language to mimic lists by encoding a sequence of natural numbers in a single natural number.
Gödel numbering
Besides using Gödel numbering to encode unique sequences of symbols into unique natural numbers (i.e. place numbers into mutually exclusive or one-to-one correspondence with the sequences), we can use it to encode whole “architectures” of sophisticated “machines”. For example, we can encode Markov algorithms, or Turing machines into natural numbers and thereby prove that the expressive power of recursive function theory is no less than that of the former machine-like formalizations of algorithms.
Accessing members
Any such representation of sequences should contain all the information as in the original sequence—most importantly, each individual member must be retrievable. However, the length does not have to match directly; even if we want to handle sequences of different length, we can store length data as a surplus member, or as the other member of an ordered pair by using a pairing function.
We expect that there is an effective way for this information retrieval process in form of an appropriate total recursive function. We want to find
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https://en.wikipedia.org/wiki/Unused%20drug
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An unused drug or leftover drug is the medicine which remains after the consumer has quit using it. Individual patients may have leftover medicines at the end of their treatment. Health care organizations may keep larger amounts of drugs as part of providing care to a community, and may have unused drugs for a range of reasons. The unused drugs should be destroyed utterly to eliminate the toxic effects of undisposed drugs on flora and fauna. The improper disposal of unused drugs could be the reason for the contamination of Surface, Ground and Drinking Water. Discharge of unused antibiotics and disinfectants in the sewage system may ruin the aquatic life or contamination of drinking water.
The determination of appropriate ways for disposal
of unused medications can predict the number of contamination problems of the environment. There are several studies which evidence the toxic effects of medications on the environment which are disposed of inappropriately.
Causes
Various circumstances may cause a consumer to have unused drugs. The consumer might find that their medication is ineffective and quit taking it. The medicine might be effective, but the consumer might not adhere to their treatment and fail to take it for any reason. A patient might die, leaving their medications behind. A patient might move, such as from a hospital to their home, and somehow leave their unused drugs behind with the health care provider.
Some medical professional practices lead to patients having unused drugs. Physicians may prescribe more than they should. Physicians and patients might see each other less often than they should, and the physician might agree to prescribe medication for a longer period of time than is best. The physician might neglect to review what medications a patient already has, and recommend more. The medical office might have confused records about what drugs a patient has, especially for offices without full computer records. Also a physician might provide drug
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https://en.wikipedia.org/wiki/NSP2%20%28rotavirus%29
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NSP2 (NS35), is a rotavirus nonstructural RNA-binding protein that accumulates in cytoplasmic inclusions (viroplasms) and is required for genome replication. NSP2 is closely associated in vivo with the viral replicase. The non-structural protein NSP5 plays a role in the structure of viroplasms mediated by its interaction with NSP2.
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https://en.wikipedia.org/wiki/Aubin%E2%80%93Lions%20lemma
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In mathematics, the Aubin–Lions lemma (or theorem) is the result in the theory of Sobolev spaces of Banach space-valued functions, which provides a compactness criterion that is useful in the study of nonlinear evolutionary partial differential equations. Typically, to prove the existence of solutions one first constructs approximate solutions (for example, by a Galerkin method or by mollification of the equation), then uses the compactness lemma to show that there is a convergent subsequence of approximate solutions whose limit is a solution.
The result is named after the French mathematicians Jean-Pierre Aubin and Jacques-Louis Lions. In the original proof by Aubin, the spaces X0 and X1 in the statement of the lemma were assumed to be reflexive, but this assumption was removed by Simon, so the result is also referred to as the Aubin–Lions–Simon lemma.
Statement of the lemma
Let X0, X and X1 be three Banach spaces with X0 ⊆ X ⊆ X1. Suppose that X0 is compactly embedded in X and that X is continuously embedded in X1. For , let
(i) If then the embedding of into is compact.
(ii) If and then the embedding of into is compact.
See also
Lions–Magenes lemma
Notes
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https://en.wikipedia.org/wiki/Centrality
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In graph theory and network analysis, indicators of centrality assign numbers or rankings to nodes within a graph corresponding to their network position. Applications include identifying the most influential person(s) in a social network, key infrastructure nodes in the Internet or urban networks, super-spreaders of disease, and brain networks. Centrality concepts were first developed in social network analysis, and many of the terms used to measure centrality reflect their sociological origin.
Definition and characterization of centrality indices
Centrality indices are answers to the question "What characterizes an important vertex?" The answer is given in terms of a real-valued function on the vertices of a graph, where the values produced are expected to provide a ranking which identifies the most important nodes.
The word "importance" has a wide number of meanings, leading to many different definitions of centrality. Two categorization schemes have been proposed. "Importance" can be conceived in relation to a type of flow or transfer across the network. This allows centralities to be classified by the type of flow they consider important. "Importance" can alternatively be conceived as involvement in the cohesiveness of the network. This allows centralities to be classified based on how they measure cohesiveness. Both of these approaches divide centralities in distinct categories. A further conclusion is that a centrality which is appropriate for one category will often "get it wrong" when applied to a different category.
Many, though not all, centrality measures effectively count the number of paths (also called walks) of some type going through a given vertex; the measures differ in how the relevant walks are defined and counted. Restricting consideration to this group allows for taxonomy which places many centralities on a spectrum from those concerned with walks of length one (degree centrality) to infinite walks (eigenvector centrality). Other centralit
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https://en.wikipedia.org/wiki/IEEE%20802.1
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IEEE 802.1 is a working group of the IEEE 802 project of the IEEE Standards Association.
It is concerned with:
802 LAN/MAN architecture
internetworking among 802 LANs, MANs and wide area networks
802 Link Security
802 overall network management
protocol layers above the MAC and LLC layers
LAN/MAN bridging and management. Covers management and the lower sub-layers of OSI Layer 2,
IEEE 802.1 standards
The IEEE 802 LAN/MAN Standards Committee makes current standards freely available, after a six-month delay, through their Get IEEE 802.1 program.
Other recent 802.1 standards are available through the IEEE for a fee.
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https://en.wikipedia.org/wiki/Costly%20state%20verification
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Costly State Verification (CSV) is an approach in contract theory that considers a contract design problem in which verification (or disclosure) of enterprise performance is costly and a lender has to pay a monitoring cost.
A central result of CSV approach is that it is generally optimal to commit to a partial, state-contingent disclosure rule. Robert M. Townsend (1979) has shown that under few strong assumptions the optimal financing mechanism is a standard debt contract for which there is no disclosure of the debtor's performance as long as debt is honored, but there is full disclosure (verification) in case of default.
Viewed from the CSV perspective, the main function of bankruptcy institutions is to establish a clear inventory of all assets and liabilities and to assess the net value of the firm.
The standard setup for financial contracting problems in CSV framework involves two risk-neutral agents, a wealth-constrained entrepreneur with an investment project, and a wealthy investor with capital available. The fixed capital invested in the project generates random cash flow at future time t with probability distribution over the possible range of profits. The entrepreneur has private information about realized cash flows from the project, but it can credibly disclose them to the investor by incurring certain cost.
The solution to this problem should provide ex-ante optimal contract structure which specify in which scenario realized cash flow should be audited and certified.
With no audit the entrepreneur would never be able to raise any money from investor since rational investor anticipates that the entrepreneur will lie about realized profit to avoid paying back to the investor.
However, in CSV framework regulated mandatory periodic disclosure of entrepreneurial performance is not efficient and imposes excessive disclosure costs.
The optimal financial contract in CSV model gives the creditor the right to all assets of the project in the event of def
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https://en.wikipedia.org/wiki/Symbolic-numeric%20computation
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In mathematics and computer science, symbolic-numeric computation is the use of software that combines symbolic and numeric methods to solve problems.
Background
Computational Algebraic Geometry
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https://en.wikipedia.org/wiki/Squalamine
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Squalamine is a steroid-polyamine conjugate compound with broad spectrum antimicrobial activity and anti-angiogenic activity. It was studied as a potential cancer drug and as a potential treatment for wet macular degeneration but as of 2018 had not succeeded in Phase III trials for any use.
Pharmacology
Squalamine disrupts microbial membranes; the exact mechanism is not known.
Squalamine appears to have an anti-angiogenic effect in mammalian cells by binding to calmodulin once it is taken up by the cell; this prevents signal transduction downstream of pro-angiogenic factors like VEGF.
Chemistry
Squalamine is a steroid-polyamine conjugate.
It was first isolated from the liver of sharks of the genus Squalus but methods to make it synthetically have been subsequently developed.
Research
Squalamine was studied as a potential drug to treat several forms of cancer and wet macular degeneration by scientists at Magainin Pharmaceuticals (subsequently called Genaera), but the company ran out of money and closed in 2009. Squalamine and some other drug assets were sold to Ohr Pharmaceutical for $200,000 by Genaera's liquidator.
It was studied in an eye drop formulation as a potential way to treat wet macular degeneration in combination with ranibizumab by Ohr Pharmaceuticals. A Phase II trial failed in 2015, but Ohr said a subpopulation with choroidal neovascularization responded well enough to justify a Phase III trial. Ohr announced that the Phase III trial had failed in January 2018.
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https://en.wikipedia.org/wiki/See-through%20display
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A see-through display or transparent display is an electronic display that allows the user to see what is shown on the screen while still being able to see through it. The main applications of this type of display are in head-up displays, augmented reality systems, digital signage, and general large-scale spatial light modulation. They should be distinguished from image-combination systems which achieve visually similar effects by optically combining multiple images in the field of view. Transparent displays embed the active matrix of the display in the field of view, which generally allows them to be more compact than combination-based systems.
Broadly, there are two types of underlying transparent display technology, absorptive (chiefly LCDs) and emissive (chiefly electroluminescent, including LEDs and "high-field" emitters). Absorptive devices work by selectively reducing the intensity of the light passing through the display, while emissive devices selectively add to the light passing through the display. Some display systems combine both absorptive and emissive devices to overcome the limitations inherent to either one. Emissive display technologies achieve partial transparency either by interspersing invisibly small opaque emitter elements with transparent areas or by being partially transparent.
History
The development of practical transparent displays accelerated rapidly around the end of first decade of the 21st century. An early commercial transparent display was the Sony Ericsson Xperia Pureness released in 2009, although it did not succeed in the market due to the screen not being visible outside or in brightly lit rooms.
Samsung released their first transparent LCD in late 2011, and Planar published a report on a prototype electroluminescent transparent display in 2012.
Not long after, UK-based Crystal Display Systems began to sell transparent LCDs remanufactured from conventional LCD displays. LG demonstrated a transparent LCD in 2015.
In the late
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https://en.wikipedia.org/wiki/Cyanoboletus%20pulverulentus
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Cyanoboletus pulverulentus, commonly known as the ink stain bolete, is an edible bolete mushroom. It is found in deciduous and mixed forests, particularly on moist soil on slopes and under beech and oak trees. A common species, it is found in northern Asia, Europe, North Africa, Central and northern South America, and eastern North America. All parts of the mushroom will stain dark bluish-black after handling. A recent study has revealed this mushroom hyperaccumulates arsenic and therefore it's consumption should be limited.
Taxonomy
Boletus pulverulentus was first described by German mycologist Wilhelm Opatowski in 1836. The specific epithet pulverulentus means "covered with powder" and refers to the somewhat dry powdery surface of the young cap and stalk. The fungus was transferred to the newly created genus Cyanoboletus in 2014, where it is the type species. Based on the 28S rDNA, North American collection of this fungus reported in the Genbank database (accession number KF030313) does not match that from Europe.
Description
The cap is convex, flat when old, dark reddish-brown becoming lighter with age, and grows up to in diameter. The flesh is yellow, with a mild taste and immediately turns blackish-blue when handled. The spore print colour is olive brown, and the stalk is long and slender, bright yellow to orange yellow at the top, and reddish-brown at the base. The mushrooms are edible, but not particularly desirable. Spores are smooth, fusoid (fuse shaped) to elliptical, and measure 11–15 by 4–6 µm. The basidia (spore-bearing cells) measure 22–35 by 6–9 µm. The cap cuticle comprises a tissue layer of undifferentiated hyphae measuring 3–7 µm wide.
Similar species
The eastern North American lookalike Boletus oliveisporus can be distinguished from C. pulverulentus by the pink to reddish colour in the center section of its stipe.
Habitat and distribution
An ectomycorrhizal species, Cyanoboletus pulverulentus forms associations with coniferous and deciduous
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https://en.wikipedia.org/wiki/The%20Racah%20Institute%20of%20Physics
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The Racah Institute of Physics () is an institute at the Hebrew University of Jerusalem, part of the faculty of Mathematics and Natural Sciences on the Edmund J. Safra Campus in the Givat Ram neighborhood of Jerusalem.
The institute is the center for all research and teaching in the various fields of physics at the Hebrew University. These include astrophysics, high energy physics, quantum physics, nuclear physics, solid state physics, laser and plasma physics, biophysics, non-linear and statistical physics, and nanophysics. Both experimental and theoretical research is carried on in these fields.
History
In 1913, before the opening of the Hebrew University, first steps towards physics research in Jerusalem were taken by Chaim Weizmann. Weizmann, the president of the Zionist Organisation, and the major figure in the planning and founding of the Hebrew University contacted Leonard Ornstein, the known physicist from Utrecht, the Netherlands, to prepare plans for physics research at the upcoming university. After the university was officially opened, he became the chairman of the physics group for several years, acting from his seat at Utrecht.
In the year 1923, two years before its official opening, Albert Einstein gave a talk on Mount Scopus, the first campus of the university, on his theory of relativity. This talk was considered by many as the opening talk of the Hebrew University.
Einstein, who supported actively the foundation and development of the Hebrew University in Jerusalem since 1919 and throughout his entire life, was particularly active in helping to establish a good physics institute.
The known mathematician, Abraham Fraenkel, who was on the governing board and served later as dean and rector of the university, invested great efforts looking for an excellent physicist to take the chair of theoretical physics in Jerusalem. He corresponded extensively with Einstein on this matter, seeking advice on the various possible candidates.
The first experim
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https://en.wikipedia.org/wiki/Membranome%20database
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Membranome database provides structural and functional information about more than 6000 single-pass (bitopic) transmembrane proteins from Homo sapiens, Arabidopsis thaliana, Dictyostelium discoideum, Saccharomyces cerevisiae, Escherichia coli and Methanocaldococcus jannaschii. Bitopic membrane proteins consist of a single transmembrane alpha-helix connecting water-soluble domains of the protein situated at the opposite sides of a biological membrane. These proteins are frequently involved in the signal transduction and communication between cells in multicellular organisms.
The database provides information about the individual proteins including computationally generated three-dimensional models of their transmembrane alpha-helices spatially arranged in the membrane, topology, intracellular localizations, amino acid sequences, domain architecture, functional annotation and available experimental structures from the Protein Data Bank. It also provides a classification of bitopic proteins into 15 functional classes, more than 700 structural superfamilies and 1400 families, along with 3D structures of bitopic protein complexes which are also classified to different families.
The second Membranome version provides 3D models of more than 2000 parallel homodimers formed by TM α-helices of bitopic proteins from different organisms which were generated using TMDOCK program. The models of the homodimers were verified through comparison with available experimental data for nearly 600 proteins. The database includes downloadable coordinate files of transmembrane helices and their homodimers with calculated membrane boundaries. Membranome 3.0 version incorporates models generated by AlphaFold 2.
The database website provides access to related webservers, FMAP and TMDOCK which have been developed for modeling individual alpha-helices and their dimeric complexes in membranes. The database and webservers were used in experimental and bioinformatics studies of bitopic membrane
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https://en.wikipedia.org/wiki/Ptenodactylus
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Ptenodactylus is a scientific name which has been used for several distinct genera of animals. It may refer to:
Ptenodactylus (Gray, 1845): A junior synonym of the lizard genus Pristidactylus
"Ptenodactylus" (Seeley, 1869): A nomen nudum which in the 19th century was used to refer to at least 21 species of pterosaur including:
"Ptenodactylus" brachyrhinus: A synonym of Ornithocheirus brachyrhinus (nomen dubium)
"Ptenodactylus" capito: A synonym of Ornithocheirus capito
"Ptenodactylus" colorhinus: A synonym of Camposipterus colorhinus.
"Ptenodactylus" crassidens: A synonym of Ornithocheirus crassidens. (nomen dubium)
"Ptenodactylus" cuvieri: A synonym of Cimoliopterus cuvieri.
"Ptenodactylus" dentatus: A synonym of Ornithocheirus dentatus. (nomen dubium)
"Ptenodactylus" enchorhynchus: A synonym of Ornithocheirus enchorhynchus (nomen dubium)
"Ptenodactylus" eurygnathus: A synonym of Ornithocheirus eurygnathus. (nomen dubium)
"Ptenodactylus" fittoni: A synonym of Pterodactylus fittoni (nomen dubium)
"Ptenodactylus" machaerorhynchus: A synonym of Lonchodraco machaerorhynchus
"Ptenodactylus macrorhinus": A nomen nudum
"Ptenodactylus" microdon: A synonym of Lonchodraco microdon
"Ptenodactylus" nasutus: A synonym of Camposipterus nasutus
"Ptenodactylus" oweni: A synonym of Lonchodraco microdon
"Ptenodactylus" oxyrhinus: A synonym of Ornithocheirus oxyrhinus (nomen dubium)
"Ptenodactylus" platystomus: A synonym of Ornithocheirus platystomus.
"Ptenodactylus" polyodon: A synonym of Ornithocheirus polyodon
"Ptenodactylus" scaphorhynchus: A synonym of Ornithocheirus scaphorhynchus. (nomen dubium)
"Ptenodactylus" sedgwicki: A synonym of Camposipterus sedgwickii.
"Ptenodactylus" tenuirostris: A synonym of Ornithocheirus tenuirostris (nomen dubium)
"Ptenodactylus" woodwardi: A synonym of Pterodactylus woodwardi (nomen dubium)
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https://en.wikipedia.org/wiki/Promoter%20bashing
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Promoter bashing is a technique used in molecular biology to identify how certain regions of a DNA strand, commonly promoters, affect the transcription of downstream genes. Under normal circumstances, proteins bind to the promoter and activate or repress transcription. In a promoter bashing assay, specific point mutations or deletions are made in specific regions of the promoter and the transcription of the gene is then measured. The contribution of a region of the promoter can be observed by the level of transcription. If a mutation or deletion changes the level of transcription, then it is known that that region of the promoter may be a binding site or other regulatory element.
Promoter bashing is often done with deletions from either the 5' or 3' end of the DNA strand; this assay is easier to perform based on repeated restriction digestion and gel-purifying fragments of specific sizes. It is often easiest to ligate the promoter into the reporter, generate a large amount of the reporter construct using PCR or growth in bacteria, and then perform serial restriction digests on this sample. The ability of upstream promoters can be easily assayed by removing segments from the 5' end, and the same for the 3' end of the strand for downstream promoters.
As the promoter commonly contains binding sequences for proteins affecting transcription, those proteins are also necessary when testing the effects of the promoter. Proteins which associate with the promoter can be identified using an electrophoretic mobility shift assay (EMSA), and the effects of inclusion or exclusion of the proteins with the mutagenized promoters can be assessed in the assay. This allows the use of promoter bashing to not only discover the location on the DNA strand which affects transcription, but also the proteins which affect that strand. The effects of protein interactions with each other as well as the binding sites can also be assayed in this way; candidate proteins must instead be identified
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https://en.wikipedia.org/wiki/Chemogenomics
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Chemogenomics, or chemical genomics, is the systematic screening of targeted chemical libraries of small molecules against individual drug target families (e.g., GPCRs, nuclear receptors, kinases, proteases, etc.) with the ultimate goal of identification of novel drugs and drug targets. Typically some members of a target library have been well characterized where both the function has been determined and compounds that modulate the function of those targets (ligands in the case of receptors, inhibitors of enzymes, or blockers of ion channels) have been identified. Other members of the target family may have unknown function with no known ligands and hence are classified as orphan receptors. By identifying screening hits that modulate the activity of the less well characterized members of the target family, the function of these novel targets can be elucidated. Furthermore, the hits for these targets can be used as a starting point for drug discovery. The completion of the human genome project has provided an abundance of potential targets for therapeutic intervention. Chemogenomics strives to study the intersection of all possible drugs on all of these potential targets.
A common method to construct a targeted chemical library is to include known ligands of at least one and preferably several members of the target family. Since a portion of ligands that were designed and synthesized to bind to one family member will also bind to additional family members, the compounds contained in a targeted chemical library should collectively bind to a high percentage of the target family.
Strategy
Chemogenomics integrates target and drug discovery by using active compounds, which function as ligands, as probes to characterize proteome functions. The interaction between a small compound and a protein induces a phenotype. Once the phenotype is characterized, we could associate a protein to a molecular event. Compared with genetics, chemogenomics techniques are able to m
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https://en.wikipedia.org/wiki/Ethylenediaminetetraacetic%20acid
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Ethylenediaminetetraacetic acid (EDTA), also called edetic acid after its own abbreviation, is an aminopolycarboxylic acid with the formula [CH2N(CH2CO2H)2]2. This white, water-soluble solid is widely used to bind to iron (Fe2+/Fe3+) and calcium ions (Ca2+), forming water-soluble complexes even at neutral pH. It is thus used to dissolve Fe- and Ca-containing scale as well as to deliver iron ions under conditions where its oxides are insoluble. EDTA is available as several salts, notably disodium EDTA, sodium calcium edetate, and tetrasodium EDTA, but these all function similarly.
Uses
Textiles and paper
In industry, EDTA is mainly used to sequester (bind or confine) metal ions in aqueous solution. In the textile industry, it prevents metal ion impurities from modifying colours of dyed products. In the pulp and paper industry, EDTA inhibits the ability of metal ions, especially Mn2+, from catalysing the disproportionation of hydrogen peroxide, which is used in chlorine-free bleaching.
Food
In a similar manner, EDTA is added to some food as a preservative or stabiliser to prevent catalytic oxidative decolouration, which is catalysed by metal ions. In soft drinks containing ascorbic acid and sodium benzoate, EDTA mitigates formation of benzene (a carcinogen).
Water softener
The reduction of water hardness in laundry applications and the dissolution of scale in boilers both rely on EDTA and related complexants to bind Ca2+, Mg2+, as well as other metal ions. Once bound to EDTA, these metal complexes are less likely to form precipitates or to interfere with the action of the soaps and detergents. For similar reasons, cleaning solutions often contain EDTA. In a similar manner EDTA is used in the cement industry for the determination of free lime and free magnesia in cement and clinkers.
The solubilisation of Fe3+ ions at or below near neutral pH can be accomplished using EDTA. This property is useful in agriculture including hydroponics. However, given the p
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https://en.wikipedia.org/wiki/Warthin%E2%80%93Finkeldey%20cell
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A Warthin–Finkeldey cell is a type of giant multinucleate cell found in hyperplastic lymph nodes early in the course of measles and also in HIV-infected individuals, as well as in Kimura disease, and more rarely in a number of neoplastic (e.g. lymphoma) and non-neoplastic lymph node disorders. Their origin is uncertain, but they have previously been shown to stain with markers similar to those of follicular dendritic cells, including CD21. Under the light microscope, these cells consist of a large, grape-like cluster of nuclei.
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https://en.wikipedia.org/wiki/Round-robin%20DNS
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Round-robin DNS is a technique of load distribution, load balancing, or fault-tolerance provisioning multiple, redundant Internet Protocol service hosts, e.g., Web server, FTP servers, by managing the Domain Name System's (DNS) responses to address requests from client computers according to an appropriate statistical model.
In its simplest implementation, round-robin DNS works by responding to DNS requests not only with a single potential IP address, but with a list of potential IP addresses corresponding to several servers that host identical services. The order in which IP addresses from the list are returned is the basis for the term round robin. With each DNS response, the IP address sequence in the list is permuted. Traditionally, IP clients initially attempt connections with the first address returned from a DNS query, so that on different connection attempts, clients would receive service from different providers, thus distributing the overall load among servers.
Some resolvers attempt to re-order the list to give priority to numerically "closer" networks. This behaviour was standardized during the definition of IPv6, and has been blamed for defeating round-robin load-balancing. Some desktop clients do try alternate addresses after a connection timeout of up to 30 seconds.
Round-robin DNS is often used to load balance requests among a number of Web servers. For example, a company has one domain name and three identical copies of the same web site residing on three servers with three IP addresses. The DNS server will be set up so that domain name has multiple A records, one for each IP address. When one user accesses the home page it will be sent to the first IP address. The second user who accesses the home page will be sent to the next IP address, and the third user will be sent to the third IP address. In each case, once the IP address is given out, it goes to the end of the list. The fourth user, therefore, will be sent to the first IP address, and
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https://en.wikipedia.org/wiki/Sociophysiology
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Sociophysiology is the "interplay between society and physical functioning" (Freund 1988: 856) involving "collaboration of two neighboring sciences: physiology and sociology" (Mauss 1936: 373). In other words, sociophysiology is physiological sociology, a special science that studies the physiological side of human (and other animals') interrelations (Zeliony 1912: 405–406).
Interdisciplinary field of research
In addition to having been termed an "interdisciplinary area for research, an area which demonstrates the concomitant relationship between physiology and social behavior" (Di Mascio et al. 1955: 4), sociophysiology may also be described as "social ethology" and "social energetics" (Waxweiler 1906: 62). That is, the "physiology of reactive phenomena caused by the mutual excitations of individuals of the same species" (Waxweiler 1906: 62).
The interdisciplinary nature of sociophysiology largely entails a "synthesis of psychophysiology and social interaction" (Adler 2002: 884) such that a "socio-psycho-biological study" (Mauss 1936: 386) of "biologico-sociological phenomena" (Mauss 1936: 385) may ensue. Such "socio-psycho-biological study" has uncovered a "sharing of physiology between people involved in a meaningful interaction" (Adler 2002: 884), as well as "mutually responsive physiologic engagement having normative function in maintaining social cohesion and well-being in higher social animals" (Adler 2002: 885). This "mutually responsive physiologic engagement" brings into play the "close links uniting social phenomena to the biological phenomena from which they immediately derive" (Solvay 1906: 26).
Interpersonal physiology
Furthermore, sociophysiology explores the "intimate relationship and mutual regulation between social and physiological systems that is especially vital in human groups" (Barchas 1986: 210). In other words, sociophysiology studies the "physio- and psycho-energetic phenomena at the basis of social groupings" (Solvay 1906: 25). Along th
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https://en.wikipedia.org/wiki/TOPSIS
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The Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) is a multi-criteria decision analysis method, which was originally developed by Ching-Lai Hwang and Yoon in 1981 with further developments by Yoon in 1987, and Hwang, Lai and Liu in 1993.
TOPSIS is based on the concept that the chosen alternative should have the shortest geometric distance from the positive ideal solution (PIS) and the longest geometric distance from the negative ideal solution (NIS). A dedicated book in the fuzzy context was published in 2021
Description
It is a method of compensatory aggregation that compares a set of alternatives, normalising scores for each criterion and calculating the geometric distance between each alternative and the ideal alternative, which is the best score in each criterion. The weights of the criteria in TOPSIS method can be calculated using Ordinal Priority Approach, Analytic hierarchy process, etc. An assumption of TOPSIS is that the criteria are monotonically increasing or decreasing.
Normalisation is usually required as the parameters or criteria are often of incongruous dimensions in multi-criteria problems. Compensatory methods such as TOPSIS allow trade-offs between criteria, where a poor result in one criterion can be negated by a good result in another criterion. This provides a more realistic form of modelling than non-compensatory methods, which include or exclude alternative solutions based on hard cut-offs. An example of application on nuclear power plants is provided in.
TOPSIS method
The TOPSIS process is carried out as follows:
Step 1 Create an evaluation matrix consisting of m alternatives and n criteria, with the intersection of each alternative and criteria given as , we therefore have a matrix .
Step 2 The matrix is then normalised to form the matrix
, using the normalisation method
Step 3 Calculate the weighted normalised decision matrix
where so that , and is the original weight given to the indicator
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https://en.wikipedia.org/wiki/Timeline%20of%20operating%20systems
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This article presents a timeline of events in the history of computer operating systems from 1951 to the current day. For a narrative explaining the overall developments, see the History of operating systems.
1950s
1951
LEO I 'Lyons Electronic Office' was the commercial development of EDSAC computing platform, supported by British firm J. Lyons and Co.
1955
MIT's Tape Director operating system made for UNIVAC 1103
1955
General Motors Operating System made for IBM 701
1956
GM-NAA I/O for IBM 704, based on General Motors Operating System
1957
Atlas Supervisor (Manchester University) (Atlas computer project start)
BESYS (Bell Labs), for IBM 704, later IBM 7090 and IBM 7094
1958
University of Michigan Executive System (UMES), for IBM 704, 709, and 7090
1959
SHARE Operating System (SOS), based on GM-NAA I/O
1960s
1960
IBSYS (IBM for its 7090 and 7094)
1961
CTSS demonstration (MIT's Compatible Time-Sharing System for the IBM 7094)
MCP (Burroughs Master Control Program)
1962
Atlas Supervisor (Manchester University) (Atlas computer commissioned)
BBN Time-Sharing System
GCOS (GE's General Comprehensive Operating System, originally GECOS, General Electric Comprehensive Operating Supervisor)
1963
AN/FSQ-32, another early time-sharing system begun
CTSS becomes operational (MIT's Compatible Time-Sharing System for the IBM 7094)
JOSS, an interactive time-shared system that did not distinguish between operating system and language
Titan Supervisor, early time-sharing system begun
1964
Berkeley Timesharing System (for Scientific Data Systems' SDS 940)
Dartmouth Time Sharing System (Dartmouth College's DTSS for GE computers)
EXEC 8 (UNIVAC)
KDF9 Timesharing Director (English Electric) – an early, fully hardware secured, fully pre-emptive process switching, multi-programming operating system for KDF9 (originally announced in 1960)
OS/360 (IBM's primary OS for its S/360 series) (announced)
PDP-6 Monitor (DEC) descendant renamed TOPS-10 in 1970
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https://en.wikipedia.org/wiki/DcGO
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dcGO is a comprehensive ontology database for protein domains. As an ontology resource, dcGO integrates Open Biomedical Ontologies from a variety of contexts, ranging from functional information like Gene Ontology to others on enzymes and pathways, from phenotype information across major model organisms to information about human diseases and drugs. As a protein domain resource, dcGO includes annotations to both the individual domains and supra-domains (i.e., combinations of two or more successive domains).
Concepts
There are two key concepts behind dcGO. The first concept is to label protein domains with ontology, for example, with Gene Ontology. That is why it is called dcGO, domain-centric Gene Ontology. The second concept is to use ontology-labeled protein domains for, for example, protein function prediction. Put it in a simple way, the first concept is about how to create dcGO resource, and the second concept is about how to use dcGO resource.
Timelines
In 2010, the algorithm behind the dcGO was initially published as an improvement to the SUPERFAMILY database.
In 2011, the 'dcGO Predictor' was ranked 10th in the 2011 CAFA competition when applied to Gene Ontology. This predictor is only domain-based method without machine learning.
In 2012, the database was officially released, published in NAR database issue.
In 2013, the webserver was improved to support many analyses using dcGO resource.
In the early 2014, the 'dcGO Predictor' was submitted for both function and phenotype predictions, ranked top in 4th in CAFA phenotype prediction.
In the late 2014, an open-source R package dcGOR was developed to help analyse ontologies and protein domain annotations.
Webserver
Recent use of dcGO is to build a domain network from a functional perspective for cross-ontology comparisons, and to combine with species tree of life (sTOL) to provide a phylogenetic context to function and phenotype.
Software
Open-source software dcGOR is developed using R programmi
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https://en.wikipedia.org/wiki/David%20Wolfe%20%28mathematician%29
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David Wolfe is a mathematician and amateur Go player.
Education and career
Wolfe graduated from Cornell University in 1985, with a bachelor's degree in electrical engineering. He obtained a Ph.D. in computer science from the University of California, Berkeley in 1994, with a dissertation Mathematics of Go: Chilling Corridors combining both subjects and supervised by Elwyn Berlekamp.
After working as a lecturer at the University of California, Berkeley from 1991 to 1996, as an associate professor at Gustavus Adolphus College from 1996 to 2008, and then as an adjunct faculty member at Dalhousie University, he moved from academia to the software industry. Wolfe was a fan of Martin Gardner and in 2009 he teamed up with Tom M. Rodgers to edit a Gardner tribute book.
Books
Wolfe is the author of books on combinatorial game theory, including:
Mathematical Go: Chilling Gets the Last Point (with Elwyn Berlekamp, A K Peters, 1994; also published as Mathematical Go Endgames: Nightmares for the Professional Go Player, Ishi Press, 1994)
Lessons in Play: An Introduction to Combinatorial Game Theory (with Michael H. Albert and Richard Nowakowski, A K Peters, 2007; 2nd ed., CRC Press, 2019)
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https://en.wikipedia.org/wiki/Hydrometeorology
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Hydrometeorology is a branch of meteorology and hydrology that studies the transfer of water and energy between the land surface and the lower atmosphere. Hydrologists often use data provided by meteorologists. As an example, a meteorologist might forecast of rain in a specific area, and a hydrologist might then forecast what the specific impact of that rain would be on the local terrain.
UNESCO has several programs and activities in place that deal with the study of natural hazards of hydrometeorological origin and the mitigation of their effects. Among these hazards are the results of natural processes and atmospheric, hydrological, or oceanographic phenomena such as floods, tropical cyclones, drought, and desertification. Many countries have established an operational hydrometeorological capability to assist with forecasting, warning, and informing the public of these developing hazards.
Hydrometeorological forecasting
One of the more significant aspects of hydrometeorology involves predictions about and attempts to mitigate the effects of high precipitation events. There are three primary ways to model meteorological phenomena in weather forecasting, including nowcasting, numerical weather prediction, and statistical techniques. Nowcasting is good for predicting events a few hours out, utilizing observations and live radar data to combine them with numerical weather prediction models. The primary technique used to forecast weather, numerical weather prediction uses mathematical models to account for the atmosphere, ocean, and many other variables when producing forecasts. These forecasts are generally used to predict events days or weeks out. Finally, statistical techniques use regressions and other statistical methods to create long-term projections that go out weeks and months at a time. These models allow scientists to visualize how a multitude of different variables interact with one another, and they illustrate one grand picture of how the Earth's clim
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https://en.wikipedia.org/wiki/Ternary%20Golay%20code
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In coding theory, the ternary Golay codes are two closely related error-correcting codes.
The code generally known simply as the ternary Golay code is an -code, that is, it is a linear code over a ternary alphabet; the relative distance of the code is as large as it possibly can be for a ternary code, and hence, the ternary Golay code is a perfect code.
The extended ternary Golay code is a [12, 6, 6] linear code obtained by adding a zero-sum check digit to the [11, 6, 5] code.
In finite group theory, the extended ternary Golay code is sometimes referred to as the ternary Golay code.
Properties
Ternary Golay code
The ternary Golay code consists of 36 = 729 codewords.
Its parity check matrix is
Any two different codewords differ in at least 5 positions.
Every ternary word of length 11 has a Hamming distance of at most 2 from exactly one codeword.
The code can also be constructed as the quadratic residue code of length 11 over the finite field F3 (i.e., the Galois Field GF(3) ).
Used in a football pool with 11 games, the ternary Golay code corresponds to 729 bets and guarantees exactly one bet with at most 2 wrong outcomes.
The set of codewords with Hamming weight 5 is a 3-(11,5,4) design.
The generator matrix given by Golay (1949, Table 1.) is
The automorphism group of the (original) ternary Golay code is the Mathieu group M11, which is the smallest of the sporadic simple groups.
Extended ternary Golay code
The complete weight enumerator of the extended ternary Golay code is
The automorphism group of the extended ternary Golay code is 2.M12, where M12 is the Mathieu group M12.
The extended ternary Golay code can be constructed as the span of the rows of a Hadamard matrix of order 12 over the field F3.
Consider all codewords of the extended code which have just six nonzero digits. The sets of positions at which these nonzero digits occur form the Steiner system S(5, 6, 12).
A generator matrix for the extended ternary Golay code is
The corresponding par
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https://en.wikipedia.org/wiki/Soler%20model
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The soler model is a quantum field theory model of Dirac fermions interacting via four fermion interactions in 3 spatial and 1 time dimension. It was introduced in 1938 by Dmitri Ivanenko
and re-introduced and investigated in 1970 by Mario Soler as a toy model of self-interacting electron.
This model is described by the Lagrangian density
where is the coupling constant,
in the Feynman slash notations, .
Here , , are Dirac gamma matrices.
The corresponding equation can be written as
,
where , ,
and are the Dirac matrices.
In one dimension,
this model is known as the massive Gross–Neveu model.
Generalizations
A commonly considered generalization is
with , or even
,
where is a smooth function.
Features
Internal symmetry
Besides the unitary symmetry U(1),
in dimensions 1, 2, and 3
the equation has SU(1,1) global internal symmetry.
Renormalizability
The Soler model is renormalizable by the power counting for and in one dimension only,
and non-renormalizable for higher values of and in higher dimensions.
Solitary wave solutions
The Soler model admits solitary wave solutions
of the form
where is localized (becomes small when is large)
and is a real number.
Reduction to the massive Thirring model
In spatial dimension 2, the Soler model coincides with the massive Thirring model,
due to the relation
,
with
the relativistic scalar
and
the charge-current density.
The relation follows from the identity
,
for any .
See also
Dirac equation
Gross–Neveu model
Nonlinear Dirac equation
Thirring model
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https://en.wikipedia.org/wiki/Joseph%20G.%20McKenna
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Joseph Gonzaga McKenna, CFC (1922 – July 28, 1973) was an American educator and member of the Congregation of Christian Brothers, a Roman Catholic religious institute. He served as the fifth president of Iona College in New Rochelle, New York.
Early life and education
McKenna was born in 1922 in New York City, where he was raised with a sister, Mary. He joined the Congregation of Christian Brothers in 1936 at the age of 14.
In 1951 he graduated from Fordham University with a master's degree, and received a PhD in 1955 from Columbia University. He additionally earned a bachelor's degree and a second master's.
Academic career
After graduating college, Brother McKenna began teaching at All Hallows Institute in 1942, and later taught at Rice High School, Iona Preparatory School, and Power Memorial Academy over the next eight years. In 1950, he became a mathematics professor at Iona College, and two years later was appointed dean of the college.
He served in that capacity until 1957, when he left New York to found Catholic Memorial High School in West Roxbury, Boston, Massachusetts, the first Christian Brothers school in New England. He served as principal there until 1963.
President of Iona College
McKenna returned to Iona College in 1963, and served there as vice president until 1965, when he became the college's 5th president. Under his leadership, the college notably changed from an all-male institution to a coeducational college. The decision, made by the college's board of trustees, was announced by McKenna in November 1968. The change in policy, which would take effect with the first female students entering Iona as freshmen in September 1969, was explained by McKenna in a press release:The change is not as drastic as one may assume. The entrance of women into the other divisions of Iona that took place during the past four years was preparing the college, whether we realized it or not, for the recent decision of the board."The decision for Iona to adopt c
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https://en.wikipedia.org/wiki/Task%20skipping
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Task skipping is an approximate computing technique that allows to skip code blocks according to a specific boolean condition to be checked at run-time.
This technique is usually applied on the most computational-intensive section of the code.
It relies on the fact that a tuple of values sequentially computed are going to be useful only if the whole tuple meet certain conditions. Knowing that a value of the tuple invalides or probably will invalidate the whole tuple, it is possible to avoid the computation of the rest of the tuple.
Code example
The example that follows provides the result of task skipping applied on this C-like source code
for (int i = 0; i < N; i++) {
value_1 = compute_1(i);
value_2 = compute_2(i);
}
Skipping a task
for (int i = 0; i < N; i++) {
value_1 = compute_1(i);
if (value_1 >= fixed_threshold) {
value_2 = compute_2(i);
}
}
See also
Loop perforation
Memoization
Software optimization
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https://en.wikipedia.org/wiki/PC%C2%B2
|
PC² is the Programming Contest Control System developed at California State University, Sacramento in support of Computer Programming Contest activities of the ACM, and in particular the ACM International Collegiate Programming Contest. It was used to conduct the ACM ICPC World Finals in 1990 and from 1994 through 2009. In 2010, the ACM ICPC World Finals switched to using Kattis, the KTH automated teaching tool; however, PC2 continues to be used for a large number of ICPC Regional Contests around the world.
Computer programming contests and PC²
Computer programming contest have rules and methods for judging submissions. The following describes in a general way a contest where PC2 is used.
A computer programming contest is a competition where teams submit (computer program) solutions to judges. The teams
are given a set of problems to solve in a limited amount of time (for example 8-13 problems in 5 hours).
The judges then give pass/fail judgements to the submitted solutions. Team rankings are computed based on the solutions, when the solutions were submitted and how many attempts were made to solve the problem. The judges test in a Black box testing where the teams do not have access to the judges' test data.
PC2 manages single or multi-site programming contests. It provides a team a way to log in, test solutions, submit solutions and view judgements from judges. PC2 provides judges a way to request team solutions (from a PC2 server) run/execute the solution and enter a judgment. The PC2 scoreboard module computes and creates standings and statistics web pages (HTML/XML). PC2 is easy to install on Linux/Linux-like systems and MS Windows and does not require super-user (root) access to install it or use it: this makes it an attractive choice for users who may not have super-user access.
Usage and User Experiences
PC2 was used for the ACM International Collegiate Programming Contest World Finals from 1994 to 2009. It has also been used in hundreds of ICPC Regio
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https://en.wikipedia.org/wiki/List%20of%20meteor%20showers
|
Named meteor showers recur at approximately the same dates each year. They appear to radiate from a certain point in the sky, known as the radiant, and vary in the speed, frequency and brightness of the meteors. As of November 2019, there are 112 established meteor showers.
Table of meteor showers
Dates are given for 2023. The dates will vary from year to year due to the leap year cycle. This list includes showers with radiants in both the northern and southern hemispheres. There is some overlap, but generally showers whose radiants have positive declinations are best seen from the northern hemisphere, and those with negative declinations are best observed from the southern hemisphere.
See also
Lists of astronomical objects
Sources
This list of meteor streams and peak activity times is based on data from the International Meteor Organization while most of the parent body associations are from Gary W. Kronk book, Meteor Showers: A Descriptive Catalog, Enslow Publishers, New Jersey, , and from Peter Jenniskens's book, "Meteor Showers and Their Parent Comets", Cambridge University Press, Cambridge UK, .
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https://en.wikipedia.org/wiki/Concurrent%20hash%20table
|
A concurrent hash table or concurrent hash map is an implementation of hash tables allowing concurrent access by multiple threads using a hash function.
Concurrent hash tables represent a key concurrent data structure for use in concurrent computing which allow multiple threads to more efficiently cooperate for a computation among shared data.
Due to the natural problems associated with concurrent access - namely contention - the way and scope in which the table can be concurrently accessed differs depending on the implementation. Furthermore, the resulting speed up might not be linear with the amount of threads used as contention needs to be resolved, producing processing overhead. There exist multiple solutions to mitigate the effects of contention, that each preserve the correctness of operations on the table.
As with their sequential counterpart, concurrent hash tables can be generalized and extended to fit broader applications, such as allowing more complex data types to be used for keys and values. These generalizations can however negatively impact performance and should thus be chosen in accordance to the requirements of the application.
Concurrent hashing
When creating concurrent hash tables, the functions accessing the table with the chosen hashing algorithm need to be adapted for concurrency by adding a conflict resolution strategy. Such a strategy requires managing accesses in a way such that conflicts caused by them do not result in corrupt data, while ideally increasing their efficiency when used in parallel.
Herlihy and Shavit describe how the accesses to a hash table without such a strategy - in its example based on a basic implementation of the Cuckoo hashing algorithm - can be adapted for concurrent use. Fan et al.
further describe a table access scheme based on cuckoo hashing that is not only concurrent, but also keeps the space efficiency of its hashing function while also improving cache locality as well as the throughput of insertions.
Wh
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https://en.wikipedia.org/wiki/Multiplication%20operator
|
In operator theory, a multiplication operator is an operator defined on some vector space of functions and whose value at a function is given by multiplication by a fixed function . That is,
for all in the domain of , and all in the domain of (which is the same as the domain of ).
This type of operator is often contrasted with composition operators. Multiplication operators generalize the notion of operator given by a diagonal matrix. More precisely, one of the results of operator theory is a spectral theorem that states that every self-adjoint operator on a Hilbert space is unitarily equivalent to a multiplication operator on an L2 space.
Example
Consider the Hilbert space of complex-valued square integrable functions on the interval . With , define the operator
for any function in . This will be a self-adjoint bounded linear operator, with domain all of and with norm . Its spectrum will be the interval (the range of the function defined on ). Indeed, for any complex number , the operator is given by
It is invertible if and only if is not in , and then its inverse is
which is another multiplication operator.
This can be easily generalized to characterizing the norm and spectrum of a multiplication operator on any Lp space.
See also
Translation operator
Shift operator
Transfer operator
Decomposition of spectrum (functional analysis)
Notes
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https://en.wikipedia.org/wiki/Spectral%20power%20distribution
|
In radiometry, photometry, and color science, a spectral power distribution (SPD) measurement describes the power per unit area per unit wavelength of an illumination (radiant exitance). More generally, the term spectral power distribution can refer to the concentration, as a function of wavelength, of any radiometric or photometric quantity (e.g. radiant energy, radiant flux, radiant intensity, radiance, irradiance, radiant exitance, radiosity, luminance, luminous flux, luminous intensity, illuminance, luminous emittance).
Knowledge of the SPD is crucial for optical-sensor system applications. Optical properties such as transmittance, reflectivity, and absorbance as well as the sensor response are typically dependent on the incident wavelength.
Physics
Mathematically, for the spectral power distribution of a radiant exitance or irradiance one may write:
where M(λ) is the spectral irradiance (or exitance) of the light (SI units: W/m2 = kg·m−1·s−3); Φ is the radiant flux of the source (SI unit: watt, W); A is the area over which the radiant flux is integrated (SI unit: square meter, m2); and λ is the wavelength (SI unit: meter, m). (Note that it is more convenient to express the wavelength of light in terms of nanometers; spectral exitance would then be expressed in units of W·m−2·nm−1.) The approximation is valid when the area and wavelength interval are small.
Relative SPD
The ratio of spectral concentration (irradiance or exitance) at a given wavelength to the concentration of a reference wavelength provides the relative SPD. This can be written as:
For instance, the luminance of lighting fixtures and other light sources are handled separately, a spectral power distribution may be normalized in some manner, often to unity at 555 or 560 nanometers, coinciding with the peak of the eye's luminosity function.
Responsivity
The SPD can be used to determine the response of a sensor at a specified wavelength. This compares the output power of the sensor to the
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https://en.wikipedia.org/wiki/MBOAT
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The MBOAT (membrane bound O-acyl transferase) family of membrane proteins is a family of various acyltransferase enzymes. All family members contain multiple transmembrane domains and most carry two conserved residues, a conserved histidine (His) embedded in a hydrophobic stretch of residues and an asparagine (Asn) or histidine within a more hydrophilic region some 30-50 residues upstream.
MBOAT enzymes catalyze the transfer of an acyl group from an acyl-coenzyme or accessory protein to one of several different substrates. The family is found from bacteria to eukaryotes.
The family may be grouped into three categories, according to function:
enzymes involved in neutral lipid biosynthesis;
enzymes involved in protein/peptide acylation;
enzymes involved in phospholipid re-modelling.
Structure
The structure for one MBOAT protein, DltB from Streptococcus thermophilus (), has been solved. DltB performs D-alanylation of cell-wall teichoic acid. It contains a ring of 11 transmembrane helices surrounding a tunnel that goes through the biological membrane. The tunnel connects to a partner, DltC, which carries the D-alanine to the conserved histidine residue of DltB MBOAT located at the bottom of the funnel. A computational model of human ghrelin O-acyltransferase (GOAT) (Q96T53) revealed a transmembrane channel that facilitates octanoylation of the peptide hormone ghrelin. DltB and GOAT share structural similarities in their homologous regions, suggesting a common core fold for MBOAT family members.
Human proteins with this domain
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https://en.wikipedia.org/wiki/Maamar%20Bettayeb
|
Maamar Bettayeb (born 7 June 1953) is a control theorist, educator and inventor. He is the author of publications on understanding the singular value decomposition and model order reduction. Bettayeb is also a promoter of scientific research.
Early years
Bettayeb continued his elementary and middle studies in Beni Amrane before joining the polyvalent high school of Tizi Ouzou in 1969 to follow his secondary studies in the Mathematics sector. After obtaining his baccalaureate in 1972 with a first class honors, he obtained a scholarship from the Algerian state to continue his university studies in the United States at the University of Southern California in Los Angeles.
He obtained his bachelor's degree in automatic control in 1976, then his master's degree in 1978.
Bettayeb obtained his PhD degree in 1981 following his defense of his thesis at the University of Southern California in the Department of Electrical Engineering, and whose title was "Approximation of Linear Systems: New Approaches Based on Singular Value Decomposition", under the supervision of Professor Emeritus Leonard M. Silverman.
Career
He worked as a research scientist for a year in Houston, Texas until 1982 in the Bellaire Research Center at Shell Oil Development Company, in the development of seismic signal processing deconvolution algorithms for the purpose of Gas and Oil exploration. Back in Algeria, he was recruited by the Center for Development of Advanced Technologies (CDTA) where he headed the instrumentation and control department from 1982 until 1988, and he led various research and development projects in the field of modeling, simulation, and control design of large scale energy systems with applications to nuclear, solar, wind and electric power systems.
He then emigrated to Saudi Arabia where he joined King Fahd University of Petroleum and Minerals in Dhahran where he worked for two years until 1990.
During the year 2000 he joined the staff of the University of Sharjah as a prof
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https://en.wikipedia.org/wiki/Track%20Imaging%20Cherenkov%20Experiment
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The Track Imaging Cherenkov Experiment (TrICE) is a ground-based cosmic ray telescope located at Argonne National Laboratory near Chicago, IL. The telescope, which contains a Fresnel lens, eight spherical mirrors, and a camera with 16 multianode photomultiplier tubes, uses the atmospheric Cherenkov imaging technique to detect Cherenkov radiation produced when cosmic rays interact with particles in the Earth's atmosphere.
The telescope is primarily a research and development tool for improving photomultiplier tube cameras and electronic systems for future gamma and cosmic ray telescopes. It is also used to study the energy and composition of cosmic rays in the TeV–PeV range, and the collaboration is currently conducting pioneering work in detecting direct Cherenkov signals from cosmic rays.
The TrICE Collaboration
Argonne National Laboratory
University of Chicago
University of Utah
Cosmic-ray telescopes
Astroparticle physics
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https://en.wikipedia.org/wiki/Split-intein%20circular%20ligation%20of%20peptides%20and%20proteins
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Split-intein circular ligation of peptides and proteins (SICLOPPS) is a biotechnology technique that permits the creation of cyclic peptides. These peptides are produced by ribosomal protein synthesis, followed by an intein-like event that splices the protein into a loop. By contrast with the nonribosomal peptide synthetases that produces some cyclic peptides like gramicidin S, SICLOPPS offers the advantage that the peptides' structure can be encoded by DNA in a simple manner according to the genetic code, but for this reason it imposes limitations on the types of amino acids incorporated that are comparable to those that apply to ordinary proteins. As implemented there is also some constraint on the peptide sequence of the cyclic sequence; for example, libraries may use the sequence SGXX..XXPL to increase the efficiency of circularization of the peptide. SICLOPPS is frequently used with a library of randomized DNA sequence that permits the simultaneous production and screening of large numbers of constructs at once, followed by the recovery of the DNA sequences responsible for the activity of the clone of interest.
A number of natural antimicrobial peptides are cyclic, and the products of SICLOPPS are "increasingly viewed as ideal backbones for modulation of protein-protein interactions." Circular peptides tend to be resistant to protease activity, and may be suitable for use as orally administered drugs. Once a cyclic peptide is identified with a biological activity of interest, it may also be possible to identify the target of the peptide (a gene that encodes a protein with which it interacts) by functional complementation, facilitating a better understanding of its mechanism of action.
See also
combinatorial chemistry
exon shuffling - note that although introns are conceptually analogous to inteins, they apply to a different molecule (RNA) and are processed by RNA splicing at a different time and location within the cell.
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https://en.wikipedia.org/wiki/Milan%20school%20of%20physics
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The Milan school of physics indicates the tradition of research in the field of physics in Milan, with particular reference to the first and second half of the 20th century, when under the impulse of Orso Mario Corbino and Antonio Garbasso, and with the chair of theoretical physics by Aldo Pontremoli, the so-called Institute of Complementary Physics of Milan was formed at the University of Milan.
History
Until the eighteenth century, the teaching of physics in Milan and generically in Italy, developed significantly in the confessional institutes, which represented, to some extent, the secular thought on the one hand and the religious tradition on the other, to then follow in the Twentieth century the events of the University. The first signs of studies, mainly based on astronomy, took place in 1764, when the Brera Astronomical Observatory was founded within the Jesuit College of Milan with the help of La Grange and subsequently of Ruggero Boscovich. It was then with Schiaparelli, a pupil of Quintino Sella and Luigi Menabrea, that the foundations were laid for modern astronomy that made Milan an astronomical center of world excellence.
First half of the 20th century (1900-1948)
In 1924 the first three absolute chairs of theoretical physics were assigned in Italy. The competition was won by Enrico Fermi, Aldo Pontremoli and Enrico Persico, who were appointed to the three chairs of some of the most prestigious Italian universities. This led Pontremoli himself to be assigned to the Lombard university, where he formed the so-called Institute of Complementary Physics, which he founded and directed, from 1924 to 1928, with the aim of founding a pole that would respond to the needs of science and technology, such as it suited the greatest Italian industrial center. Having had a part of the school building in via Sacchini available, he took care of the adaptation and the fixed installations so that the new Institute could carry out scientific and didactic activities eff
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https://en.wikipedia.org/wiki/Pancreatic%20veins
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In human anatomy, the pancreatic veins consist of several small blood vessels which drain the body and tail of the pancreas, and open into the trunk of the great pancreatic vein.
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https://en.wikipedia.org/wiki/Instructions%20per%20cycle
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In computer architecture, instructions per cycle (IPC), commonly called instructions per clock, is one aspect of a processor's performance: the average number of instructions executed for each clock cycle. It is the multiplicative inverse of cycles per instruction.
Explanation
While early generations of CPUs carried out all the steps to execute an instruction sequentially, modern CPUs can do many things in parallel. As it is impossible to just keep doubling the speed of the clock, instruction pipelining and superscalar processor design have evolved so CPUs can use a variety of execution units in parallel - looking ahead through the incoming instructions in order to optimise them. This leads to the instructions per cycle completed being much higher than 1 and is responsible for much of the speed improvements in subsequent CPU generations.
Calculation of IPC
The calculation of IPC is done through running a set piece of code, calculating the number of machine-level instructions required to complete it, then using high-performance timers to calculate the number of clock cycles required to complete it on the actual hardware. The final result comes from dividing the number of instructions by the number of CPU clock cycles.
The number of instructions per second and floating point operations per second for a processor can be derived by multiplying the number of instructions per cycle with the clock rate (cycles per second given in Hertz) of the processor in question. The number of instructions per second is an approximate indicator of the likely performance of the processor.
The number of instructions executed per clock is not a constant for a given processor; it depends on how the particular software being run interacts with the processor, and indeed the entire machine, particularly the memory hierarchy. However, certain processor features tend to lead to designs that have higher-than-average IPC values; the presence of multiple arithmetic logic units (an ALU is
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https://en.wikipedia.org/wiki/Louis-Jeantet%20Prize%20for%20Medicine
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Established in 1986, the Louis-Jeantet Prizes are funded by the Fondation Louis-Jeantet and awarded each year to experienced researchers who have distinguished themselves in the field of biomedical research in one of the member states of the Council of Europe. They are not intended solely as the recognition of work that has been completed, but also to encourage the continuation of innovative research projects. The prizes are awarded to fully active researchers whose scientific efforts are focused on biomedical research. When the research being recognised is close to practical applications for combating illnesses affecting humankind, one of the Louis-Jeantet Prizes converts into a Jeantet-Collen Prize for Translational Medicine, supported by generous donations from the Désiré Collen Stichting.
The particular research domains in which prizes have been awarded are physiology, biophysics, structural biology, biochemistry, cellular and molecular biology, developmental biology and genetics; prize-winners have worked in immunology, virology, bacteriology, neurobiology, clinical epidemiology and structural biochemistry.
The Prize is endowed with 1.4 million Swiss francs. The sum available to each prize-winner amounts to 500'000 francs, of which 450'000 francs are to be used for financing ongoing research and 50'000 francs are given to the researcher personally.
Prize winners
List of winners:
See also
Latsis Foundation
List of medicine awards
Louis-Jeantet Foundation
Marcel Benoist Prize
Prizes named after people
Notes and references
External links
Official website
Medicine awards
Awards established in 1986
Swiss awards
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https://en.wikipedia.org/wiki/Formate%20dehydrogenase
|
Formate dehydrogenases are a set of enzymes that catalyse the oxidation of formate to carbon dioxide, donating the electrons to a second substrate, such as NAD+ in formate:NAD+ oxidoreductase () or to a cytochrome in formate:ferricytochrome-b1 oxidoreductase (). This family of enzymes has attracted attention as inspiration or guidance on methods for the carbon dioxide fixation, relevant to global warming.
Function
NAD-dependent formate dehydrogenases are important in methylotrophic yeast and bacteria, being vital in the catabolism of C1 compounds such as methanol. The cytochrome-dependent enzymes are more important in anaerobic metabolism in prokaryotes. For example, in E. coli, the formate:ferricytochrome-b1 oxidoreductase is an intrinsic membrane protein with two subunits and is involved in anaerobic nitrate respiration.
NAD-dependent reaction
Formate + NAD+ CO2 + NADH + H+
Cytochrome-dependent reaction
Formate + 2 ferricytochrome b1 CO2 + 2 ferrocytochrome b1 + 2 H+
Molybdopterin, molybdenum and selenium dependence
The metal-dependent Fdh's feature Mo or W at their active sites. These active sites resemble the motif seen in DMSO reductase, with two molybdopterin cofactors bound to Mo/W in a bidentate fashion. The fifth and sixth ligands are sulfide and either cysteinate or selenocysteinate.
The mechanism of action appears to involve 2e redox of the metal centers, induced by hydride transfer from formate and release of carbon dioxide:
In this scheme, represents the four thiolate-like ligands provided by the two dithiolene cofactors, the molybdopterins. The dithiolene and cysteinyl/selenocysteinyl ligands are redox-innocent. In terms of the molecular details, the mechanism remains uncertain, despite numerous investigations. Most mechanisms assume that formate does not coordinate to Mo/W, in contrast to typical Mo/W oxo-transferases (e.g., DMSO reductase). A popular mechanistic proposal entails transfer of H- from formate to the Mo/WVI=S group.
T
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https://en.wikipedia.org/wiki/Evolutionary%20algorithm
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In computational intelligence (CI), an evolutionary algorithm (EA) is a subset of evolutionary computation, a generic population-based metaheuristic optimization algorithm. An EA uses mechanisms inspired by biological evolution, such as reproduction, mutation, recombination, and selection. Candidate solutions to the optimization problem play the role of individuals in a population, and the fitness function determines the quality of the solutions (see also loss function). Evolution of the population then takes place after the repeated application of the above operators.
Evolutionary algorithms often perform well approximating solutions to all types of problems because they ideally do not make any assumption about the underlying fitness landscape. Techniques from evolutionary algorithms applied to the modeling of biological evolution are generally limited to explorations of microevolutionary processes and planning models based upon cellular processes. In most real applications of EAs, computational complexity is a prohibiting factor. In fact, this computational complexity is due to fitness function evaluation. Fitness approximation is one of the solutions to overcome this difficulty. However, seemingly simple EA can solve often complex problems; therefore, there may be no direct link between algorithm complexity and problem complexity.
Implementation
The following is an example of a generic single-objective genetic algorithm.
Step One: Generate the initial population of individuals randomly. (First generation)
Step Two: Repeat the following regenerational steps until termination:
Evaluate the fitness of each individual in the population (time limit, sufficient fitness achieved, etc.)
Select the fittest individuals for reproduction. (Parents)
Breed new individuals through crossover and mutation operations to give birth to offspring.
Replace the least-fit individuals of the population with new individuals.
Types
Similar techniques differ in genetic representati
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https://en.wikipedia.org/wiki/Tiabendazole
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Tiabendazole (INN, BAN), also known as thiabendazole (AAN, USAN) or TBZ and the trade names Mintezol, Tresaderm, and Arbotect, is a preservative, an antifungal agent, and an antiparasitic agent.
Uses
Preservative
Tiabendazole is used primarily to control mold, blight, and other fungal diseases in fruits (e.g. oranges) and vegetables; it is also used as a prophylactic treatment for Dutch elm disease.
Tiabendazole is also used as a food additive, a preservative with E number E233 (INS number 233). For example, it is applied to bananas to ensure freshness, and is a common ingredient in the waxes applied to the skins of citrus fruits. It is not approved as a food additive in the EU, Australia and New Zealand.
Use in treatment of aspergillosis has been reported.
It is also used in anti-fungal wallboards as a mixture with azoxystrobin.
Parasiticide
As an antiparasitic, tiabendazole is able to control roundworms (such as those causing strongyloidiasis), hookworms, and other helminth species which infect wild animals, livestock, and humans.
Other
In dogs and cats, tiabendazole is used to treat ear infections.
Tiabendazole is also a chelating agent, which means it is used medicinally to bind metals in cases of metal poisoning, such as lead, mercury, or antimony poisoning.
Research
Genes responsible for the maintenance of cell walls in yeast have been shown to be responsible for angiogenesis in vertebrates. Tiabendazole serves to block angiogenesis in both frog embryos and human cells. It has also been shown to serve as a vascular disrupting agent to reduce newly established blood vessels. Tiabendazole has been shown to effectively do this in certain cancer cells.
Pharmacodynamics
Tiabendazole works by inhibition of the mitochondrial, helminth-specific enzyme, fumarate reductase, with possible interaction with endogenous quinone.
Safety
The substance appears to have a slight toxicity in higher doses, with effects such as liver and intestinal disorders at h
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https://en.wikipedia.org/wiki/Inpainting
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Inpainting is a conservation process where damaged, deteriorated, or missing parts of an artwork are filled in to present a complete image. This process is commonly used in image restoration. It can be applied to both physical and digital art mediums such as oil or acrylic paintings, chemical photographic prints, sculptures, or digital images and video.
With its roots in physical artwork, such as painting and sculpture, traditional inpainting is performed by a trained art conservator who has carefully studied the artwork to determine the mediums and techniques used in the piece, potential risks of treatments, and ethical appropriateness of treatment.
History
The modern use of inpainting can be traced back to Pietro Edwards (1744–1821), Director of the Restoration of the Public Pictures in Venice, Italy. Using a scientific approach, Edwards focused his restoration efforts on the intentions of the artist.
It was during the 1930 International Conference for the Study of Scientific Methods for the Examination and Preservation of Works of Art, that the modern approach to inpainting was established. Helmut Ruhemann (1891–1973), a German restorer and conservator, led the discussions on the use of inpainting in conservation. Helmut Ruhemann was a leading figure in modernizing restoration and conservation. His greatest contribution to the field of conservation "was his insistence on following the methods of the original painter exactly, and on understanding the painter's artistic intention". After his career of over 40 years as a conservator, Ruhemann published his treatise The Cleaning of Paintings: Problems & Potentialities in 1968. In describing his method, Ruhemann states that "The surface [of the fill] should be slightly lower than that of the surrounding paint to allow for the thickness of the inpainting...Inpainting medium should look and behave like the original medium, but must not darken with age." Cesare Brandi (1906–1988) developed the teoria del restauro,
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https://en.wikipedia.org/wiki/Asynchronous%20communication
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In telecommunications, asynchronous communication is transmission of data, generally without the use of an external clock signal, where data can be transmitted intermittently rather than in a steady stream. Any timing required to recover data from the communication symbols is encoded within the symbols.
The most significant aspect of asynchronous communications is that data is not transmitted at regular intervals, thus making possible variable bit rate, and that the transmitter and receiver clock generators do not have to be exactly synchronized all the time. In asynchronous transmission, data is sent one byte at a time and each byte is preceded by start and stop bits.
Physical layer
In asynchronous serial communication in the physical protocol layer, the data blocks are code words of a certain word length, for example octets (bytes) or ASCII characters, delimited by start bits and stop bits. A variable length space can be inserted between the code words. No bit synchronization signal is required. This is sometimes called character oriented communication. Examples include MNP2 and modems older than V.2.
Data link layer and higher
Asynchronous communication at the data link layer or higher protocol layers is known as statistical multiplexing, for example Asynchronous Transfer Mode (ATM). In this case, the asynchronously transferred blocks are called data packets, for example ATM cells. The opposite is circuit switched communication, which provides constant bit rate, for example ISDN and SONET/SDH.
The packets may be encapsulated in a data frame, with a frame synchronization bit sequence indicating the start of the frame, and sometimes also a bit synchronization bit sequence, typically 01010101, for identification of the bit transition times. Note that at the physical layer, this is considered as synchronous serial communication. Examples of packet mode data link protocols that can be/are transferred using synchronous serial communication are the HDLC, Ethernet
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https://en.wikipedia.org/wiki/OpenQASM
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Open Quantum Assembly Language (OpenQASM; pronounced open kazm) is a programming language designed for describing quantum circuits and algorithms for execution on quantum computers. It is designed to be an intermediate representation that can be used by higher-level compilers to communicate with quantum hardware, and allows for the description of a wide range of quantum operations, as well as classical feed-forward flow control based on measurement outcomes.
The language includes a mechanism for describing explicit timing of instructions, and allows for the attachment of low-level definitions to gates for tasks such as calibration. OpenQASM is not intended for general-purpose classical computation, and hardware implementations of the language may not support the full range of data manipulation described in the specification. Compilers for OpenQASM are expected to support a wide range of classical operations for compile-time constants, but the support for these operations on runtime values may vary between implementations.
The language was first described in a paper published in July 2017, and a reference source code implementation was released as part of IBM's Quantum Information Software Kit (Qiskit) for use with their IBM Quantum Experience cloud quantum computing platform. The language has similar qualities to traditional hardware description languages such as Verilog.
OpenQASM defines its version at the head of a source file as a number, as in the declaration: OPENQASM 3;
The level of OpenQASM's original published implementations is OpenQASM 2.0. Version 3.0 of the specification is the current one and can be viewed at the OpenQASM repository on GitHub.
Examples
The following is an example of OpenQASM source code from the official library. The program adds two four-bit numbers.
/*
* quantum ripple-carry adder
* Cuccaro et al, quant-ph/0410184
*/
OPENQASM 3;
include "stdgates.inc";
gate majority a, b, c {
cx c, b;
cx c, a;
ccx a, b, c;
}
ga
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https://en.wikipedia.org/wiki/Superstructure%20%28condensed%20matter%29
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In solid state physics, a superstructure is some additional structure that is superimposed on a higher symmetry crystalline structure. A typical and important example is ferromagnetic ordering.
In a wider sense, the term "superstructure" is applied to polymers and proteins to describe ordering on a length scale larger than that of monomeric segments.
In crystals
In a crystal, a superstructure manifests itself through additional reflections in diffraction patterns, e.g., in low energy electron diffraction (LEED) or X-ray diffraction experiments. Often a set of weak diffraction spots appears between the stronger spots belonging to what is referred to as the substructure. In some cases a phase transition occurs, e.g., at higher temperatures, where the superstructure disappears and the material reverts to the simpler substructure. Not all compounds exhibit a superstructure.
The superspots in diffraction patterns represent a modulation of the substructure that causes the inherent translation symmetry of the (substructure) lattice to be violated slightly or the size of the repeat motif of the structure to be increased. One could speak of symmetry breaking of the translation symmetry of the lattice, although rotational symmetry may be lost simultaneously.
Commensurate cases
If the superspots are located at simple fractions of the vectors of the reciprocal lattice of the substructure, e.g., at q=(½,0,0), the resulting broken symmetry is a multiple of the unit cell along that axis. Such a modulation is called a commensurate superstructure.
Incommensurate cases
In some materials, superspots will occur at positions that do not represent a simple fraction, say q=(0.5234,0,0). In this case the structure strictly speaking has lost all translational symmetry in a particular direction. This is called an incommensurate structure.
Causes
There are basically three types of superstructures in crystals:
Magnetic superstructures
When a crystalline material that contains atoms wi
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https://en.wikipedia.org/wiki/Self-limiting%20%28biology%29
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In biology and medicine, the term self-limiting may describe a medical condition, or it may describe an organism or colony.
Self-limiting organisms and colonies
A self-limiting organism or colony of organisms limits its own growth by its actions. For example, a single organism may have a maximum size determined by genetics, or a colony of organisms may release waste which is ultimately toxic to the colony once it exceeds a certain population. In some cases, the self-limiting nature of a colony may be advantageous to the continued survival of the colony, such as in the case of parasites. If their numbers became too high, they would kill the host, and thus themselves. In other cases, self-limitation restricts the viability of predators, thus ensuring the long-term survival of rare species.
Self-limiting medical conditions
When referring to a medical condition the term may imply that a condition would run its course without the need of external influence, especially any medical treatment. However, the fact that a condition may be self-limiting does not mean that medical treatment would not bring the condition or its symptoms to an end more quickly, or that such medical attention would be unnecessary in severe cases.
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https://en.wikipedia.org/wiki/MacOS%20Ventura
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macOS Ventura (version 13) is the nineteenth major release of macOS, Apple's operating system for Macintosh computers. The successor to macOS Monterey, it was announced at WWDC 2022 on June 6, 2022, and launched on October 24, 2022. macOS Ventura is succeeded by macOS Sonoma, which was released on September 26, 2023.
It is named after Ventura County and is the tenth macOS release to bear a name from the company's home state of California. The macOS 13 Ventura logo, official graphics and default wallpaper resemble an abstract California poppy.
macOS Ventura is the last version of macOS supporting Macs without Retina display, especially the 21.5-inch 2017 iMac and the 12-inch MacBook, as its successor, macOS Sonoma, drops support for those models.
History
New features
macOS Ventura includes changes, many related to productivity, and adds two apps from iOS and iPadOS: Weather and Clock. Freeform was added in an update to all three operating systems.
New system features
Stage Manager, which provides an alternative interface for multitasking, in addition to the previous Mission Control.
New apps
Weather: shows detailed weather forecasts. Clicking on the Weather widget now opens this app, not The Weather Channel's website.
Clock: displays world time and manages alarms, stopwatches, and timers. Clicking on the Clock widget now opens this app, not the Date & Time section of System Preferences.
Freeform, a whiteboard app that supports real-time collaboration (added in version 13.1).
Changes
Mail adds "send later" and "undo send" options and includes improvements to search, email organization, and formatting.
Spotlight produces richer search results; with Live Text, it can return pictures that contain the queried text.
Safari adds Shared Tab Groups and Passkeys, uses WebAuthn for password-less account management, gets a redesigned sidebar, and gains AVIF support.
Messages now allows the user to edit and unsend recent iMessages, similar to iOS and iPadOS 16.
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https://en.wikipedia.org/wiki/Chemometrics
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Chemometrics is the science of extracting information from chemical systems by data-driven means. Chemometrics is inherently interdisciplinary, using methods frequently employed in core data-analytic disciplines such as multivariate statistics, applied mathematics, and computer science, in order to address problems in chemistry, biochemistry, medicine, biology and chemical engineering. In this way, it mirrors other interdisciplinary fields, such as psychometrics and econometrics.
Background
Chemometrics is applied to solve both descriptive and predictive problems in experimental natural sciences, especially in chemistry. In descriptive applications, properties of chemical systems are modeled with the intent of learning the underlying relationships and structure of the system (i.e., model understanding and identification). In predictive applications, properties of chemical systems are modeled with the intent of predicting new properties or behavior of interest. In both cases, the datasets can be small but are often large and complex, involving hundreds to thousands of variables, and hundreds to thousands of cases or observations.
Chemometric techniques are particularly heavily used in analytical chemistry and metabolomics, and the development of improved chemometric methods of analysis also continues to advance the state of the art in analytical instrumentation and methodology. It is an application-driven discipline, and thus while the standard chemometric methodologies are very widely used industrially, academic groups are dedicated to the continued development of chemometric theory, method and application development.
Origins
Although one could argue that even the earliest analytical experiments in chemistry involved a form of chemometrics, the field is generally recognized to have emerged in the 1970s as computers became increasingly exploited for scientific investigation. The term 'chemometrics' was coined by Svante Wold in a 1971 grant application, and
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https://en.wikipedia.org/wiki/Modern%20Hopfield%20network
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Modern Hopfield networks (also known as Dense Associative Memories) are generalizations of the classical Hopfield networks that break the linear scaling relationship between the number of input features and the number of stored memories. This is achieved by introducing stronger non-linearities (either in the energy function or neurons’ activation functions) leading to super-linear (even an exponential) memory storage capacity as a function of the number of feature neurons. The network still requires a sufficient number of hidden neurons.
The key theoretical idea behind the Modern Hopfield networks is to use an energy function and an update rule that is more sharply peaked around the stored memories in the space of neuron’s configurations compared to the classical Hopfield network.
Classical Hopfield networks
Hopfield networks are recurrent neural networks with dynamical trajectories converging to fixed point attractor states and described by an energy function. The state of each model neuron is defined by a time-dependent variable , which can be chosen to be either discrete or continuous. A complete model describes the mathematics of how the future state of activity of each neuron depends on the known present or previous activity of all the neurons.
In the original Hopfield model of associative memory, the variables were binary, and the dynamics were described by a one-at-a-time update of the state of the neurons. An energy function quadratic in the was defined, and the dynamics consisted of changing the activity of each single neuron only if doing so would lower the total energy of the system. This same idea was extended to the case of being a continuous variable representing the output of neuron , and being a monotonic function of an input current. The dynamics became expressed as a set of first-order differential equations for which the "energy" of the system always decreased. The energy in the continuous case has one term which is quadratic in the (a
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https://en.wikipedia.org/wiki/Self-domestication
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Self-domestication is a scientific hypothesis that suggests that, similar to domesticated animals, there has been a process of artificial selection among members of the human species conducted by humans themselves. In this way, during the process of hominization, a preference for individuals with collaborative and social behaviors would have been shown to optimize the benefit of the entire group: docility, language, and emotional intelligence would have been enhanced during this process of artificial selection. The hypothesis is raised that this is what differentiated Homo sapiens from Homo neanderthalensis and Homo erectus.
Origin and status of the hypothesis
In general, domesticated animals possess common characteristics that differentiate them from their non-domesticated counterparts (for example, in the case of Canis familiaris compared to their relatives, Canis lupus, among many other cases): they tend to be more docile and playful, exhibit less aggressive behavior, and show marked neoteny, often resulting in a smaller body, a slightly smaller brain and skull, as well as shorter teeth and snout.
One of the first to scientifically observe that humans present similar traits was the naturalist, anthropologist, and physician Johann Friedrich Blumenbach around 1800. The author of the thesis "De generis humani varietate nativa" ('On the natural variations in the human lineage') consequently proposed the hypothesis that humans could have been domesticated.
A few years later, Charles Darwin addressed the topic using the theory of evolution, which already considered the process of artificial selection in animals. Unable to explain the concept of human domestication from an exclusively scientific perspective (the question of who domesticated humans could only be answered in religious or theistic terms), he eventually dismissed the hypothesis.
However, the studies of Dimitri Beliayev in the 20th century were important for the proposal: research on the silver fox demo
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https://en.wikipedia.org/wiki/NTSC-C
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NTSC-C is a regional lockout created in 2003 by Sony Computer Entertainment for the official launch of its PlayStation 2 gaming system into the mainland Chinese market.
Mainland Chinese market
The system's original model, then called PlayStation 2, was launched throughout 2000, 2001 and 2002 in Japan, North America, Europe, Oceania and Southeast Asia, but it was not introduced in mainland China because of rampant piracy. In November 2003, Sony China Chairman Hiroshi Soda explained the situation:
However the situation changed in November 2003 as Sony China announced the PlayStation 2 (SCPH-50009 "Satin Silver" type) was planned to be launched in mainland China for Christmas, official release date December 20, 2003. Sales would be first limited to five large industrialized cities Beijing, Shanghai, Guangzhou, Shenzhen and Chengdu, then distribution would start in the whole country. However, on the eve of Christmas, arguing an "unfavorable environment," Sony China delayed the mainland release to next year with the system's new "slimline" type PS2 and sales limited to Shanghai and Guangzhou. Meanwhile, Kenichi Fukunaga, a Sony Japan spokesman in Tokyo, reportedly declared "the company simply had not prepared in time for the China launch."
The "NTSC/C" regional lockout for mainland China was specially created as the system is also a home NTSC DVD player with its specific Zone 6 regional code which is not compatible with the bordering countries (Japan is Zone 2; South Korea, Hong Kong, and Taiwan are all Zone 3, etc.)
The first batch of NTSC/C games was released in December 2005. Along with Sony Computer Entertainment Japan, third-party publishers included local branches of Bandai and Namco among others. The model types of NTSC-C PS2 for mainland China were SCPH-70006 CB, SCPH-75006 CB, SCPH-77006 CB, and SCPH-90006 CB.
Marketing definition
"C" stands for China. However Hong Kong, Macau and Taiwan are part of the NTSC-J region which was initially created for Japan.
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https://en.wikipedia.org/wiki/Pseudo%20Stirling%20cycle
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The pseudo Stirling cycle, also known as the adiabatic Stirling cycle, is a thermodynamic cycle with an adiabatic working volume and isothermal heater and cooler, in contrast to the ideal Stirling cycle with an isothermal working space. The working fluid has no bearing on the maximum thermal efficiencies of the pseudo Stirling cycle.
Practical Stirling engines usually use a adiabatic Stirling cycle as the ideal Stirling cycle can not be practically implemented.
Nomenclature (practical engines and ideal cycle are both named Stirling) and lack in specificity (omitting ideal or adiabatic Stirling cycle) can cause confusion.
History
The pseudo Stirling cycle was designed to address predictive shortcomings in the ideal isothermal Stirling cycle. Specifically, the ideal cycle does not give usable figures or criteria for judging the performance of real-world Stirling engines.
See also
Stirling engine
Stirling cycle
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https://en.wikipedia.org/wiki/Current%20yield
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The current yield, interest yield, income yield, flat yield, market yield, mark to market yield or running yield is a financial term used in reference to bonds and other fixed-interest securities such as gilts. It is the ratio of the annual interest (coupon) payment and the bond's price:
According to Investopedia, the clean market price of the bond should be the denominator in this calculation.
Example
The current yield of a bond with a face value (F) of $100 and a coupon rate (r) of 5.00% that is selling at $95.00 (clean; not including accrued interest) (P) is calculated as follows.
Shortcomings of current yield
The current yield refers only to the yield of the bond at the current moment. It does not reflect the total return over the life of the bond, or the factors affecting total return, such as:
the length of time over which the bond produces cash flows for the investor (the maturity date of the bond),
interest earned on reinvested coupon payments, or reinvestment risk (the uncertainty about the rate at which future cash flows can be reinvested), and
fluctuations in the market price of a bond prior to maturity.
Relationship between yield to maturity and coupon rate
The concept of current yield is closely related to other bond concepts, including yield to maturity (YTM), and coupon yield. When a coupon-bearing bond sells at;
a discount: YTM > current yield > coupon yield
a premium: coupon yield > current yield > YTM
par: YTM = current yield = coupon yield.
For zero-coupon bonds selling at a discount, the coupon yield and current yield are zero, and the YTM is positive.
See also
Adjusted current yield
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https://en.wikipedia.org/wiki/IEEEXtreme
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IEEEXtreme (often abbreviated as Xtreme) is an annual hackathon and competitive programming challenge in which teams of IEEE Student members, often supported by an IEEE Student Branch and proctored by an IEEE member, compete in a 24-hour time span against each other to solve a set of programming problems. The competition is underwritten and coordinated by IEEE's Membership and Geographic Activities department, and is often supported by partnering sponsors, like IEEE Computer Society.
History
IEEEXtreme was created in 2006 by Marko Delimar and Ricardo Varela who, at the time, were with the IEEE Student Activities Committee. The first instance of IEEEXtreme was held in 2006 with a global participation of 44 teams and 150 contestants. The numbers more than tripled the second time it was held, in 2008, to 130 teams with 500 participants. The iteration of IEEEXtreme in 2015, enjoyed the registration of over 2,300 teams, participation of over 1,900 teams, 5,500+ student competitors, 600+ proctors, and 100+ volunteers around the world.
Competition rules
Teams of up to three student IEEE members receive sets of programming problems over 24 hours, starting at 0:00 UTC on the competition date. All teams receive the same problems to solve and are expected to solve the problems without direct outside consultation. Teams don’t need to tackle every problem, but the more they solve, the more points they score. Students submit their solutions using an online tool, which has been HackerRank in recent years. Points are awarded based on how the problem was solved, the time it took, and its difficulty. Higher-grade IEEE members serve as judges and proctors for the competition.
The competition is free, but IEEE Student Membership is required to participate. Students - undergraduate and graduate - are welcome to register as IEEE Student Members and participants in IEEEXtreme on the same day. The cost of IEEE Student Membership varies from country to country.
Yearly results
IEEEXt
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https://en.wikipedia.org/wiki/Pierce%20oscillator
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The Pierce oscillator is a type of electronic oscillator particularly well-suited for use in piezoelectric crystal oscillator circuits. Named for its inventor, George W. Pierce (1872–1956), the Pierce oscillator is a derivative of the Colpitts oscillator. Virtually all digital IC clock oscillators are of Pierce type, as the circuit can be implemented using a minimum of components: a single digital inverter, one resistor, two capacitors, and the quartz crystal, which acts as a highly selective filter element. The low manufacturing cost of this circuit and the outstanding frequency stability of the quartz crystal give it an advantage over other designs in many consumer electronics applications.
Operation
If the circuit consists of perfect lossless components, the signal on C1 and C2 will be proportional to the impedance of each, and the ratio of the signal voltages at C1 and C2 will be C2/C1. With C1 and C2 equal size (a common configuration), the current in C1 to C2 would be exactly equal, but out of phase, requiring no current from the amplifier or voltage gain from the amplifier, and allowing a high output impedance amplifier, or the use of an isolating series resistance in the amplifier output. Normal crystals are lossless enough to make this a reasonable approximation: the amplifier does not drive the resonant circuit, but merely stays in sync with it, providing enough power to match losses.
A series resistor is occasionally shown in the amplifier output. When used, a series resistor reduces loop gain, and amplifier gain must be increased to restore total loop gain to unity. The purpose of using such a resistor in the amplifier circuit is to increase phase shift at startup, or when the crystal circuit is pulled out of phase by loading, and to eliminate the effects of amplifier non-linearity and of crystal overtones or spurious modes. It is not part of the basic operation of the Pierce topology.
Biasing resistor
R1 acts as a feedback resistor, biasing the i
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https://en.wikipedia.org/wiki/Bioelectrochemistry
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Bioelectrochemistry is a branch of electrochemistry and biophysical chemistry concerned with electrophysiological topics like cell electron-proton transport, cell membrane potentials and electrode reactions of redox enzymes.
History
The beginnings of bioelectrochemistry, as well as those of electrochemistry, are closely related to physiology through the works of Luigi Galvani and then Alessandro Volta.
The first modern work in this field is considered that of the German physiologist Julius Bernstein (1902) concerning the source of biopotentials due to different ion concentration through the cell's membrane.
The domain of bioelectrochemistry has grown considerably over the past century, maintaining the close connections to various medical and biological and engineering disciplines like electrophysiology, biomedical engineering, and enzyme kinetics. The achievements in this field have been awarded several Nobel prizes for Physiology or Medicine. Among prominent electrochemists who have contributed to this field one could mention John Bockris.
See also
Biomedical engineering
Bioelectronics
Bioelectrochemical reactor
Biomagnetism
Enzymatic biofuel cell
Protein Film Voltammetry
Saltatory conduction
Notes
External links
Johann Wilhelm Ritter contribution to the field
Electrochemistry
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https://en.wikipedia.org/wiki/KIX%20domain
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In biochemistry, the KIX domain (kinase-inducible domain (KID) interacting domain) or CREB binding domain is a protein domain of the eukaryotic transcriptional coactivators CBP and P300. It serves as a docking site for the formation of heterodimers between the coactivator and specific transcription factors. Structurally, the KIX domain is a globular domain consisting of three α-helices and two short 310-helices.
The KIX domain was originally discovered in 1996 as the specific and minimal region in CBP that binds and interacts with phosphorylated CREB to activate transcription. It was thus first termed CREB-binding domain. However, when it was later discovered that it also binds many other proteins, the more general name KIX domain became favoured. The KIX domain contains two separate binding sites: the "c-Myb site", named after the oncoprotein c-Myb, and the "MLL site", named after the proto-oncogene MLL (Mixed Lineage Leukemia, KMT2A).
The paralogous coactivators CBP (CREBBP) and P300 (EP300) are recruited to DNA-bound transcription factors to activate transcription. Coactivators can associate with promoters and enhancers in the DNA only indirectly through protein-protein contacts with transcription factors. CBP and P300 activate transcription synergistically in two ways: first, by remodelling and relaxing chromatin through their intrinsic histone acetyltransferase activity, and second, by recruiting the basal transcription machinery, such as RNA polymerase II.
The KIX domain belongs to the proposed GACKIX domain superfamily. GACKIX comprises structurally and functionally highly homologous domains in related proteins. It is named after the protein GAL11 / ARC105 (MED15), the plant protein CBP-like, and the KIX domain from CBP and P300. Additional instances include RECQL5 and related plant proteins. All of these contain a KIX domain or KIX-related domain that interacts with the transactivation domain of many different transcription factors. The distinction betwee
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https://en.wikipedia.org/wiki/Galaksija%20BASIC
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Galaksija BASIC was the BASIC interpreter of the Galaksija build-it-yourself home computer from Yugoslavia. While being partially based on code taken from TRS-80 Level 1 BASIC, which the creator believed to have been a Microsoft BASIC, the extensive modifications of Galaksija BASIC—such as to include rudimentary array support, video generation code (as the CPU itself did it in absence of dedicated video circuitry) and generally improvements to the programming language—is said to have left not much more than flow-control and floating point code remaining from the original.
The core implementation of the interpreter was fully contained in the 4 KiB ROM "A" or "1". The computer's original mainboard had a reserved slot for an extension ROM "B" or "2" that added more commands and features such as a built-in Zilog Z80 assembler.
ROM "A"/"1" symbols and keywords
The core implementation, in ROM "A" or "1", contained 3 special symbols and 32 keywords:
begins a comment (equivalent of standard BASIC REM command)
Equivalent of standard BASIC DATA statement
prefix for hex numbers
Allocates an array of strings, like DIM, but can allocate only array with name A$
serves as PEEK when used as a function (e.g. PRINT BYTE(11123)) and POKE when used as a command (e.g. BYTE 11123,123).
Calls BASIC subroutine as GOSUB in most other BASICs (e.g. CALL 100+4*X)
converts an ASCII numeric code into a corresponding character (string)
draws (command) or inspects (function) a pixel at given coordinates (0<=x<=63, 0<=y<=47).
displays the clock or time controlled by content of Y$ variable. Not in standard ROM
causes specified program line to be edited
standard part of IF-ELSE construct (Galaksija did not use THEN)
compare alphanumeric values X$ and Y$
standard FOR loop
standard GOTO command
equivalent of standard BASIC CLS command - clears the screen
protects n characters from the top of the screen from being scrolled away
standard part of IF-EL
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https://en.wikipedia.org/wiki/T.%20R.%20Ramadas
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Trivandrum Ramakrishnan "T. R." Ramadas (born 30 March 1955) is an Indian mathematician who specializes in algebraic and differential geometry, and mathematical physics. He was awarded the Shanti Swarup Bhatnagar Prize for Science and Technology in 1998, the highest science award in India, in the mathematical sciences category.
He studied engineering in IIT Kanpur then joined TIFR as a graduate student in physics finally changing to mathematics after his interactions with M S Narasimhan.
He is currently a professor at Chennai Mathematical Institute, Chennai, Tamil Nadu.
Selected publications
"The "Harder-Narasimhan Trace" and Unitarity of the KZ/Hitchin Connection: genus 0", Ann. of Math. 169, 1–39 (2009).
(With V.B. Mehta) "Moduli of vector bundles, Frobenius splitting, and invariant theory", Ann. of Math. 144, 269–313 (1996).
"Factorisation of generalised theta functions II", Topology 35, 641–654 (1996).
(With M.S. Narasimhan) "Factorisation of generalised theta functions I", Invent. Math. 114, 565–624 (1993).
(With I.M. Singer and J. Weitsman) "Some comments on Chern Simons gauge theory", Commun. Math. Phys. 126, 409–420 (1989).
(With P.K. Mitter) "The two-dimensional O(N) nonlinear =E5 model: renormalisation and effective actions", Commun. Math. Phys. 122, 575–596 (1989).
(With M.S. Narasimhan) "Geometry of SU(2) gauge fields", Commun. Math. Phys. 67, 121–136 (1979).
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https://en.wikipedia.org/wiki/Uroguanylin
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Uroguanylin is a 16 amino acid peptide that is secreted by enterochromaffin cells in the duodenum and proximal small intestine. Guanylin acts as an agonist of the guanylyl cyclase receptor guanylate cyclase 2C (GC-C), and regulates electrolyte and water transport in intestinal and renal epithelia. By agonizing this guanylyl cyclase receptor, uroguanylin and guanylin cause intestinal secretion of chloride and bicarbonate to dramatically increase; this process is helped by the second messenger cGMP. Its sequence is H-Asn-Asp-Asp-Cys(1)-Glu-Leu-Cys(2)-Val-Asn-Val-Ala-Cys(1)-Thr-Gly-Cys(2)-Leu-OH.
In humans, the uroguanylin peptide is encoded by the GUCA2B gene. Uroguanylin may be involved in appetite and perceptions of 'fullness' after eating meals, as suggested by a study into mice.
See also
Natriuretic peptide
Plecanatide – a medication structurally related to uroguanylin
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https://en.wikipedia.org/wiki/Fermentative%20hydrogen%20production
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Fermentative hydrogen production is the fermentative conversion of organic substrates to H2. Hydrogen produced in this manner is often called biohydrogen. The conversion is effected by bacteria and protozoa, which employ enzymes. Fermentative hydrogen production is one of several anaerobic conversions.
Dark vs photofermentation
Dark fermentation reactions do not require light energy. These are capable of constantly producing hydrogen from organic compounds throughout the day and night. Typically these reactions are coupled to the formation of carbon dioxide or formate. Important reactions that result in hydrogen production start with glucose, which is converted to acetic acid:
C6H12O6 + 2 H2O → 2 CH3CO2H + 2 CO2 + 4 H2
A related reaction gives formate instead of carbon dioxide:
C6H12O6 + 2 H2O → 2 CH3CO2H + 2 HCO2H + 2 H2
These reactions are exergonic by 216 and 209 kcal/mol, respectively.
Using synthetic biology, bacteria can be genetically altered to enhance this reaction.
Photofermentation differs from dark fermentation, because it only proceeds in the presence of light. Electrohydrogenesis is used in microbial fuel cells.
Bacteria strains
For example, photo-fermentation with Rhodobacter sphaeroides SH2C can be employed to convert small molecular fatty acids into hydrogen.
Enterobacter aerogenes is an outstanding hydrogen producer. It is an anaerobic facultative and mesophilic bacterium that is able to consume different sugars and in contrast to cultivation of strict anaerobes, no special operation is required to remove all oxygen from the fermenter. E. aerogenes has a short doubling time and high hydrogen productivity and evolution rate. Furthermore, hydrogen production by this bacterium is not inhibited at high hydrogen partial pressures; however, its yield is lower compared to strict anaerobes like Clostridia. A theoretical maximum of 4 mol H2/mol glucose can be produced by strict anaerobic bacteria. Facultative anaerobic bacteria s
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https://en.wikipedia.org/wiki/Glossary%20of%20tensor%20theory
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This is a glossary of tensor theory. For expositions of tensor theory from different points of view, see:
Tensor
Tensor (intrinsic definition)
Application of tensor theory in engineering science
For some history of the abstract theory see also multilinear algebra.
Classical notation
Ricci calculus
The earliest foundation of tensor theory – tensor index notation.
Order of a tensor
The components of a tensor with respect to a basis is an indexed array. The order of a tensor is the number of indices needed. Some texts may refer to the tensor order using the term degree or rank.
Rank of a tensor
The rank of a tensor is the minimum number of rank-one tensor that must be summed to obtain the tensor. A rank-one tensor may be defined as expressible as the outer product of the number of nonzero vectors needed to obtain the correct order.
Dyadic tensor
A dyadic tensor is a tensor of order two, and may be represented as a square matrix. In contrast, a dyad is specifically a dyadic tensor of rank one.
Einstein notation
This notation is based on the understanding that whenever a multidimensional array contains a repeated index letter, the default interpretation is that the product is summed over all permitted values of the index. For example, if aij is a matrix, then under this convention aii is its trace. The Einstein convention is widely used in physics and engineering texts, to the extent that if summation is not to be applied, it is normal to note that explicitly.
Kronecker delta
Levi-Civita symbol
Covariant tensor
Contravariant tensor
The classical interpretation is by components. For example, in the differential form aidxi the components ai are a covariant vector. That means all indices are lower; contravariant means all indices are upper.
Mixed tensor
This refers to any tensor that has both lower and upper indices.
Cartesian tensor
Cartesian tensors are widely used in various branches of continuum mechanics, such as fluid mechanics and elasticity. In cl
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https://en.wikipedia.org/wiki/Philips%20SAA1099
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The Philips SAA1099 sound generator is a 6-voice sound chip used by some 1980s devices.
It can produce several different waveforms by locking the volume envelope generator to the frequency generator, and also has a noise generator with 3 preset frequencies which can be locked to the frequency generator for greater range. It can output audio in fully independent stereo.
Uses
The following sound cards and computers used the SAA1099:
Silicon Graphics IRIS Professional 4D and IRIS Power 4D machines, released in 1987 and 1988, used the SAA1099 on the IO2 and IO3 board for sound generation. Although this feature was almost never documented or used, the chip is present and usable if addressed directly.
The Creative Music System (C/MS) by Creative Labs, released in 1987, and also marketed at RadioShack as the Game Blaster, released in 1988. These devices contain two SAA1099 chips, for twelve voices.
The Creative Sound Blaster 1.0 card released in 1989 (and 1.5 and 2.0 as an optional addon), included the SAA1099 chips, in addition to the OPL2 chip (aka YM3812), which became much more popular.
The British-made SAM Coupé computer released in 1989, with a single SAA1099 on the motherboard.
Various arcade games and the System 5 family used the SAA1099.
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https://en.wikipedia.org/wiki/Assignment%20of%20copyright%20in%20software%20under%20Indian%20Copyright%20Act
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Ownership and assignment of copyright for computer software in India was addressed by the Delhi High Court in a judgment on Pine Labs Private Limited vs Gemalto Terminals India Private Limited and others (FAO 635 of 2009 and FAO 636 of 2009).
Justice A.K. Sikri and Justice Suresh Kait upheld Pine Labs' contention that the assignment of copyright in software developed by it for Gemalto came to an end after 5 years and thereafter, the copyright reverted to Pine Labs.
Facts
Gemalto had engaged Pine Labs for the development of software for various programs including the one for the IOCL Fleet Card Program. A master service agreement (MSA) was signed in June 2004. Clause 7 of the MSA provided that Pine Labs " assigns" all copyright to Gemalto. Pursuant to the MSA, Pine Labs authored a computer program known as the Version 1.03 for the IOCL Fleet Card Program and a complete version of the same was provided to Gemalto in August 2004. Thereafter, certain other functionalities were added to the program and subsequent versions were also provided from time to time. In 2009, Pine Labs filed a suit in the Delhi high Court claiming that copyright had reverted to it as the assignment had expired by virtue of section 19(5) and 19(6) of the Indian Copyright Act.
Section 19(5) and 19(6) provide that:
19(5) If the period of assignment is not stated, it shall be deemed to be five years from the date of assignment.
19 (6) If the territorial extent of assignment of the rights is not specified, it shall be presumed to extend within India.
Injunction
Ex parte injunction was granted by the Single judge but was later vacated after hearing arguments. Pine Labs filed an appeal before the Division Bench. Division Bench initially granted interim stay and vide judgment dated 3 August 2011 ruled in favour of Pine Labs.
Judgment
The bench observed that:
The Bench relied upon section 19(5) and 19(6) of the Copyright Act and came to the conclusion that:
Gemalto contended that the MSA was on
|
https://en.wikipedia.org/wiki/FIGlet
|
FIGlet is a computer program that generates text banners, in a variety of typefaces, composed of letters made up of conglomerations of smaller ASCII characters (see ASCII art). The name derives from "Frank, Ian and Glenn's letters".
Being free software, FIGlet is commonly included as part of many Unix-like operating systems (Linux, BSD, etc.) distributions, but it has been ported to other platforms as well. The official FIGlet FTP site includes precompiled ports for the Acorn, Amiga, Apple II, Atari ST, BeOS, Mac, MS-DOS, NeXTSTEP, OS/2, and Microsoft Windows, as well as a reimplementation in Perl (Text::FIGlet). There are third-party reimplementations of FIGlet in Java (including one embedded in the JavE ASCII art editor), JavaScript, PHP, Python, and Go.
Behavior
FIGlet can read from standard input or accept a message as part of the command line. It prints to standard output. Some common arguments (options) are:
-f to select a font file. (font files are available here)
-d to change the directory for fonts.
-c centers the output.
-l left-aligns the output.
-r right-aligns the output.
-t sets the output width to the terminal width.
-w specifies a custom output width.
-k enables kerning, printing each letter of the message individually, instead of merged into the adjacent letters.
Sample usage
An example of output generated by FIGlet is shown below.
[user@hostname ~]$ figlet Wikipedia
__ ___ _ _ _ _
\ \ / (_) | _(_)_ __ ___ __| (_) __ _
\ \ /\ / /| | |/ / | '_ \ / _ \/ _` | |/ _` |
\ V V / | | <| | |_) | __/ (_| | | (_| |
\_/\_/ |_|_|\_\_| .__/ \___|\__,_|_|\__,_|
|_|
The following command:
[user@hostname ~]$ figlet -ct -f roman Wikipedia
generates this output:
oooooo oooooo oooo o8o oooo o8o .o8 o8o
`888. `888. .8' `"' `888 `"' "888 `"'
`88
|
https://en.wikipedia.org/wiki/Decoy%20cells
|
Decoy cells are virally infected epithelial cells that can be found in the urine. Decoy cells owe their name to their strong resemblance to cancer cells, and may as such confuse the diagnosis of either viral infection or urothelial malignancy. During 1950s, cytotechnologist Andrew Ricci observed cells mimicking cancer cells by they were not, in a group of persons working in some kinds of industries - they were referred to as “decoy cells”, analogous to “decoy ducks” used in hunting wild ducks, by Andrew Ricci, a cytotechnologist working renown cytopathologist Dr. Leopold G. Koss.
Epidemiology and presentation
Decoy cells are mostly prevalent in immunocompromised individuals, such as transplant recipients who are treated with immunosuppressive medication in order for their immune system not to reject the foreign transplanted organ. Several viruses mediated the emergence of decoy cells, amongst which cytomegalovirus and polyomavirus. Decoy cells are virus infected urothelial cells with a distinct morphology of enlarged nuclei and intranuclear inclusions. In renal transplant recipients, such cells may be found in up to 40 percent of cases. Decoy cells are clinically relevant since they may be used as a prognostic marker for clinical conditions such as polyomavirus BK-induced nephropathy in renal transplant recipients, and haemorrhagic cystitis in haematopoietic stem cell transplant recipients.
Diagnosis
Decoy cells can be seen in a urine sample through Papanicolaou staining or phase-contrast microscopy. By Papanicolaou stain, most decoy cells have an enlarged nucleus that bears a basophilic inclusion which is surrounded by chromatin that confers a ground-glass or gelatinous appearance. Sometimes the nuclear inclusion has a vesicular aspect, the chromatin may be clumped, and it may be surrounded by a halo. When decoy cells derive from the urothelium, the heavily enlarged and altered nuclei as well as the irregular shape of the cell body can mimic the changes observed
|
https://en.wikipedia.org/wiki/Unit%20type
|
In the area of mathematical logic and computer science known as type theory, a unit type is a type that allows only one value (and thus can hold no information). The carrier (underlying set) associated with a unit type can be any singleton set. There is an isomorphism between any two such sets, so it is customary to talk about the unit type and ignore the details of its value. One may also regard the unit type as the type of 0-tuples, i.e. the product of no types.
The unit type is the terminal object in the category of types and typed functions. It should not be confused with the zero or bottom type, which allows no values and is the initial object in this category. Similarly, the Boolean is the type with two values.
The unit type is implemented in most functional programming languages. The void type that is used in some imperative programming languages serves some of its functions, but because its carrier set is empty, it has some limitations (as detailed below).
In programming languages
Several computer programming languages provide a unit type to specify the result type of a function with the sole purpose of causing a side effect, and the argument type of a function that does not require arguments.
In Haskell, Rust, and Elm, the unit type is called () and its only value is also (), reflecting the 0-tuple interpretation.
In ML descendants (including OCaml, Standard ML, and F#), the type is called unit but the value is written as ().
In Scala, the unit type is called Unit and its only value is written as ().
In Common Lisp the type named is a unit type which has one value, namely the symbol . This should not be confused with the type, which is the bottom type.
In Python, there is a type called NoneType which allows the single value of None.
In Swift, the unit type is called Void or () and its only value is also (), reflecting the 0-tuple interpretation.
In Java, the unit type is called Void and its only value is null.
In Go, the unit type is written struct
|
https://en.wikipedia.org/wiki/Undertone%20series
|
In music, the undertone series or subharmonic series is a sequence of notes that results from inverting the intervals of the overtone series. While overtones naturally occur with the physical production of music on instruments, undertones must be produced in unusual ways. While the overtone series is based upon arithmetic multiplication of frequencies, resulting in a harmonic series, the undertone series is based on arithmetic division.
Terminology
The hybrid term subharmonic is used in music in a few different ways. In its pure sense, the term subharmonic refers strictly to any member of the subharmonic series (, , , , etc.). When the subharmonic series is used to refer to frequency relationships, it is written with f representing some highest known reference frequency (, , , , etc.). As such, one way to define subharmonics is that they are "... integral submultiples of the fundamental (driving) frequency". The complex tones of acoustic instruments do not produce partials that resemble the subharmonic series, unless they are played or designed to induce non-linearity. However, such tones can be produced artificially with audio software and electronics. Subharmonics can be contrasted with harmonics. While harmonics can "... occur in any linear system", there are "... only fairly restricted conditions" that will lead to the "nonlinear phenomenon known as subharmonic generation".
In a second sense, subharmonic does not relate to the subharmonic series, but instead describes an instrumental technique for lowering the pitch of an acoustic instrument below what would be expected for the resonant frequency of that instrument, such as a violin string that is driven and damped by increased bow pressure to produce a fundamental frequency lower than the normal pitch of the same open string. The human voice can also be forced into a similar driven resonance, also called “undertone singing” (which similarly has nothing to do with the undertone series), to extend the range of
|
https://en.wikipedia.org/wiki/List%20of%20botanists%20by%20author%20abbreviation%20%28W%E2%80%93Z%29
|
A–V
To find entries for A–V, use the table of contents above.
W
W.A.Archer – William Andrew Archer (1894–1973)
W.A.Bell – Walter Andrew Bell (1889–1969)
W.A.Clark – William Andrew Clark (1911–1983)
W.A.Clarke – William Ambrose Clarke (1841–1911)
Waddell – Coslett Herbert Waddell (1858–1919)
Wade – Walter Wade (1760–1825)
Wadhwa – Brij Mohan Wadhwa (1933–2009)
Wad.Khan – M. A. Wadood Khan (1944–2023)
Waga – Jakub Ignacy Waga (1800–1872)
Wagenitz – (1927–2017)
Wagstaff – Steven J. Wagstaff (fl. 1998)
Wahl – Herbert Alexander Wahl (1900–1975)
Wahlenb. – Göran Wahlenberg (1780–1851)
Waisb. – Anton Waisbecker (1835–1916)
Waldst. – Franz de Paula Adam von Waldstein (1759–1823)
Wall. – Nathaniel Wallich (1786–1854)
Wallace – Alfred Russel Wallace (1823–1913)
Wallander – Eva Wallander (born 1968)
Wallays – Antoine Charles François Wallays (1812–1888)
Wallenwein – Fritz Wallenwein (fl. 2012)
Wallerius – Johan Gottschalk Wallerius (1709–1785)
Walleyn – Ruben Walleyn (1966–2008)
Wallis – Gustav Wallis (1830–1878)
Wallman – Johan Haquin Wallman (1792–1853)
Walln. – Anton Wallnöfer (fl. 1888)
Wallner – Joseph Wallner (1909–1935)
Wallossek – Christoph Wallossek (fl. 1999)
Wallr. – Karl Friedrich Wilhelm Wallroth (1792–1857)
Wallwork – H. Wallwork (fl. 1988)
Walp. – Wilhelm Gerhard Walpers (1816–1853)
Walter – Thomas Walter (1740–1789)
Walters – Stuart Max Walters (1920–2005)
W.Anderson – William Anderson (1750–1778)
Wangenh. – Friedrich Adam Julius von Wangenheim (1749–1800)
Wangerin – Walther Wangerin (1884–1938)
Wanggai – Jack Wanggai (fl. 2000)
Wapstra – Mark Wapstra (born 1971)
Warb. – Otto Warburg (1859–1938)
W.Archer – William Archer (1830–1897)
W.Archer bis – William Archer (1820–1874)
Ward – Lester Frank Ward (1841–1913)
Ward.-Johnson – Greg Wardell-Johnson (fl. 1996)
Warder – John Aston Warder (1812–1883)
Wardle – Peter Wardle (1931–2008)
Warion – (Jean Pierre) Adrien Warion (1837–1880)
Warm. – Johannes Eugenius Bülo
|
https://en.wikipedia.org/wiki/SHARC%20molecular%20dynamics%20software
|
SHARC (Surface Hopping including ARbitrary Couplings) is an ab initio molecular dynamics program suite primarily dedicated to study the excited-state dynamics of molecules. It is free for academic use, open source released under the GNU General Public License.
History
The SHARC software suite was made publicly available in October 2014. It is developed by the SHARC development team in the group of Prof. Leticia_González at the Institute of Theoretical Chemistry at the University of Vienna, Austria.
Features
The SHARC molecular dynamics software can treat non-adiabatic couplings at conical intersections, intersystem crossing induced by spin-orbit coupling, and laser couplings on an equal footing. It has interfaces to the ab initio software packages MOLPRO, MOLCAS, ORCA_(quantum_chemistry_program), Gaussian_(software), TURBOMOLE, COLUMBUS (needs MOLCAS), BAGEL and to user-created LVC (linear vibronic coupling) models, to machine learning properties via the SchNarc approach, as well as to a tool for analytical potentials. Furthermore, it includes auxiliary Python scripts for setup, maintenance and analysis of ensembles of trajectories.
Applications
The underlying methodology is based on Surface hopping, a semiclassical technique in computational chemistry. SHARC extends this method to treat spin-orbit couplings and laser interactions on an equal footing in addition to the originally included non-adiabatic effects. It has been applied to study strong laser interactions in the IBr molecule. Further applications, deal with photorelaxation in SO2, cytosine, and uracil
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https://en.wikipedia.org/wiki/Lists%20of%20flags
|
This is a collection of lists of flags, including the flags of states or territories, groups or movements and individual people.
There are also lists of historical flags and military flag galleries. Many of the flag images are on Wikimedia Commons.
In Wikipedia
Gallery of sovereign state flags
List of country subdivision flags
Lists of city flags
List of flags by design
List of national flags by design
List of national flags by aspect ratio
List of flags by color
List of flags by number of colors
Gallery of flags of dependent territories
Flags of country subdivisions
Timeline of national flags
International maritime signal flags
Lists of naval flags
In Wikimedia Commons
Gallery of flags by design
Category:Flags
Index of country subdivisions
Index of historical flags by year
States or territories
Extinct states flags
City flags
Capital city flags
Astronomical flags
Unrecognized states flags
Categories about Flags
Flags by content
Flags by country
Flag divisions
Flag elements
Country subdivision flags
Historical flags
State flags
State flags and ensigns
Special and fictional flags
Army and Ground Force flags
Air Force Ensigns
Border and Coast Guard Force Ensigns
Ministry of Defense flags
Naval Jacks
Nautical flags
Police Flags
Civil air ensigns
Civil and Merchant Navy Flags
Pilot boat flags and ensigns
Yacht flags and ensigns
Flags of international organizations
Groups or movements
Cultural and ethnic flags
Flags of active autonomist and secessionist movements
Flags of Native Americans in the United States
Flags of Aboriginal peoples of Canada
Flags of French-speaking people of North America
Political flags
Religious flags
International flags
Sexual identity symbols (including flags)
Flags of micronations
Personal standards
Head of state standards
Historical flags
Historical flags
Flags of Yugoslavia
Soviet Republic flags
Historical flags by country
Military flag galleries
Flags of the United State
|
https://en.wikipedia.org/wiki/Lambda%20diode
|
A lambda diode is an electronic circuit that combines a complementary pair of junction gated field effect transistors into a two-terminal device that exhibits an area of differential negative resistance much like a tunnel diode. The term refers to the shape of the V–I curve of the device, which resembles the Greek letter λ (lambda).
Lambda diodes work at higher voltage than tunnel diodes. Whereas a typical tunnel diode may exhibit negative differential resistance approximately between 70 mV and 350 mV, this region occurs approximately between 1.5 V and 6 V in a lambda diode due to the higher pinch-off voltages of typical JFET devices. A lambda diode therefore cannot replace a tunnel diode directly.
Moreover, in a tunnel diode the current reaches a minimum of about 20% of the peak current before rising again towards higher voltages. The lambda diode current approaches zero as voltage increases, before rising quickly again at a voltage high enough to cause gate–source Zener breakdown in the FETs.
It is also possible to construct a device similar to a lambda diode by combining an n-channel JFET with a PNP bipolar transistor.
A suggested modulatable variant but is a bit more difficult to build uses a PNP based optocoupler and can be tweaked by using its IR diode. This has the advantage that its properties can be fine tuned with a simple bias driver and used for high sensitivity radio applications, sometimes a modified open can PNP transistor with IR LED can be used instead.
Applications
Like the tunnel diode, the negative resistance aspect of the lambda diode lends itself naturally to application in oscillator circuits and amplifiers. In addition, bistable circuits such as memory cells have been described.
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https://en.wikipedia.org/wiki/Cyclic%20order
|
In mathematics, a cyclic order is a way to arrange a set of objects in a circle. Unlike most structures in order theory, a cyclic order is not modeled as a binary relation, such as "". One does not say that east is "more clockwise" than west. Instead, a cyclic order is defined as a ternary relation , meaning "after , one reaches before ". For example, [June, October, February], but not [June, February, October], cf. picture. A ternary relation is called a cyclic order if it is cyclic, asymmetric, transitive, and connected. Dropping the "connected" requirement results in a partial cyclic order.
A set with a cyclic order is called a cyclically ordered set or simply a cycle. Some familiar cycles are discrete, having only a finite number of elements: there are seven days of the week, four cardinal directions, twelve notes in the chromatic scale, and three plays in rock-paper-scissors. In a finite cycle, each element has a "next element" and a "previous element". There are also cyclic orders with infinitely many elements, such as the oriented unit circle in the plane.
Cyclic orders are closely related to the more familiar linear orders, which arrange objects in a line. Any linear order can be bent into a circle, and any cyclic order can be cut at a point, resulting in a line. These operations, along with the related constructions of intervals and covering maps, mean that questions about cyclic orders can often be transformed into questions about linear orders. Cycles have more symmetries than linear orders, and they often naturally occur as residues of linear structures, as in the finite cyclic groups or the real projective line.
Finite cycles
A cyclic order on a set with elements is like an arrangement of on a clock face, for an -hour clock. Each element in has a "next element" and a "previous element", and taking either successors or predecessors cycles exactly once through the elements as .
There are a few equivalent ways to state this definition. A cyclic
|
https://en.wikipedia.org/wiki/Paromomycin
|
Paromomycin is an antimicrobial used to treat a number of parasitic infections including amebiasis, giardiasis, leishmaniasis, and tapeworm infection. It is a first-line treatment for amebiasis or giardiasis during pregnancy. Otherwise, it is generally a second line treatment option. It is taken by mouth, applied to the skin, or by injection into a muscle.
Common side effects when taken by mouth include loss of appetite, vomiting, abdominal pain, and diarrhea. When applied to the skin side effects include itchiness, redness, and blisters. When given by injection there may be fever, liver problems, or hearing loss. Use during breastfeeding appears to be safe. Paromomycin is in the aminoglycoside family of medications and causes microbe death by stopping the creation of bacterial proteins.
Paromomycin was discovered in the 1950s from a type of streptomyces and came into medical use in 1960. It is on the World Health Organization's List of Essential Medicines. Paromomycin is available as a generic medication.
Medical uses
It is an antimicrobial used to treat intestinal parasitic infections such as cryptosporidiosis and amoebiasis, and other diseases such as leishmaniasis.
Paromomycin was demonstrated to be effective against cutaneous leishmaniasis in clinical studies in the USSR in the 1960s, and in trials with visceral leishmaniasis in the early 1990s.
The route of administration is intramuscular injection and capsule.
Paromomycin topical cream with or without gentamicin is an effective treatment for ulcerative cutaneous leishmaniasis, according to the results of a phase-3, randomized, double-blind, parallel group–controlled trial.
Pregnancy and breastfeeding
The medication is poorly absorbed. The effect it may have on the baby is still unknown.
There is limited data regarding the safety of taking paromomycin while breastfeeding but because the drug is poorly absorbed minimal amounts of drug will be secreted in breastmilk.
HIV/AIDS
There is limited evidence t
|
https://en.wikipedia.org/wiki/Terradynamics
|
Terradynamics is the study of forces and movement during terrestrial locomotion (particularly that using legs) on ground that can flow such as sand and soil. The term "terradynamics" is used in analogy to aerodynamics for flying in the air and hydrodynamics for swimming in water. Terradynamics has been used "to predict a small legged robot’s locomotion on granular media".
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https://en.wikipedia.org/wiki/Pre-B%C3%B6tzinger%20complex
|
The preBötzinger complex, often abbreviated as preBötC, is a functionally and anatomically specialized site in the ventral-lateral region of the lower medulla oblongata (i.e., lower brainstem). The preBötC is part of the ventral respiratory group of respiratory related interneurons. Its foremost function is to generate the inspiratory breathing rhythm in mammals. In addition, the preBötC is widely and paucisynaptically connected to higher brain centers that regulate arousal and excitability more generally such that respiratory brain function is intimately connected with many other rhythmic and cognitive functions of the brain and central nervous system. Further, the preBötC receives mechanical sensory information from the airways that encode lung volume as well as pH, oxygen, and carbon dioxide content of circulating blood and the cerebrospinal fluid.
The preBötC is approximately colocated with the hypoglossal (XII) cranial motor nucleus as well as the ‘loop’ portion of the inferior olive in the anterior-posterior axis. The caudal border of the preBötC is slightly caudal to the obex, where the brainstem merges with the cervical spinal cord.
Discovery
The initial description of the preBötC was widely disseminated in a 1991 paper in Science, but its discovery predates that paper by one year. The team was led by Jack L. Feldman and Jeffrey C. Smith at the University of California, Los Angeles (UCLA), but the Science paper also included UCLA coauthor Howard Ellenberger, as well as Klaus Ballanyi and Diethelm W. Richter from Göttingen University in Germany. The region derives its name from a neighboring medullary region involved in expiratory breathing rhythm dubbed Bötzinger complex, which was named after the Silvaner (Bötzinger) variety of wine, featured at the conference at which that region was named (click here to hear a BBC interview with Jack Feldman on the topic of Bötzinger / preBötzinger nomenclature).
Functional definition of the preBötC
The first defini
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https://en.wikipedia.org/wiki/Binomial%20approximation
|
The binomial approximation is useful for approximately calculating powers of sums of 1 and a small number x. It states that
It is valid when and where and may be real or complex numbers.
The benefit of this approximation is that is converted from an exponent to a multiplicative factor. This can greatly simplify mathematical expressions (as in the example below) and is a common tool in physics.
The approximation can be proven several ways, and is closely related to the binomial theorem. By Bernoulli's inequality, the left-hand side of the approximation is greater than or equal to the right-hand side whenever and .
Derivations
Using linear approximation
The function
is a smooth function for x near 0. Thus, standard linear approximation tools from calculus apply: one has
and so
Thus
By Taylor's theorem, the error in this approximation is equal to for some value of that lies between 0 and . For example, if and , the error is at most . In little o notation, one can say that the error is , meaning that .
Using Taylor series
The function
where and may be real or complex can be expressed as a Taylor series about the point zero.
If and , then the terms in the series become progressively smaller and it can be truncated to
This result from the binomial approximation can always be improved by keeping additional terms from the Taylor series above. This is especially important when starts to approach one, or when evaluating a more complex expression where the first two terms in the Taylor series cancel (see example).
Sometimes it is wrongly claimed that is a sufficient condition for the binomial approximation. A simple counterexample is to let and . In this case but the binomial approximation yields . For small but large , a better approximation is:
Example
The binomial approximation for the square root, , can be applied for the following expression,
where and are real but .
The mathematical form for the binomial approximation
|
https://en.wikipedia.org/wiki/The%20Plant%20List
|
The Plant List was a list of botanical names of species of plants created by the Royal Botanic Gardens, Kew and the Missouri Botanical Garden and launched in 2010. It was intended to be a comprehensive record of all known names of plant species over time, and was produced in response to Target 1 of the 2002–2010 Global Strategy for Plant Conservation (GSP C), to produce "An online flora of all known plants". It has not been updated since 2013, and has been superseded by World Flora Online.
World Flora Online
In October 2012, the follow-up project World Flora Online was launched with the aim to publish an online flora of all known plants by 2020. This is a project of the United Nations Convention on Biological Diversity, with the aim of halting the loss of plant species worldwide by 2020. It is developed by a collaborative group of institutions around the world response to the 2011-2020 GSPC's updated Target 1. This aims to achieve an online Flora of all known plants by 2020. It was conceived in 2012 by an initial group of four institutions; the Missouri Botanical Garden, the New York Botanical Garden, the Royal Botanic Garden Edinburgh and the Royal Botanic Gardens, Kew.
There is a complementary project called the International Plant Names Index, in which Kew is also involved. The IPNI aims to provide details of publication and does not aim to determine which are accepted species names. Newly published names are automatically added from IPNI to the World Checklist of Selected Plant Families, a database which underlies the Plant List.
Findings
The Plant List has 1,064,035 scientific plant names of species rank, of which 350,699 are accepted species names, belonging to 642 plant families and 17,020 plant genera.
The Plant List accepts approximately 350,699 unique species, with 470,624 synonyms for those species, which suggests that many species have been referred to under more than one name. , The Plant List has determined that another 243,000 names are "unresolved
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https://en.wikipedia.org/wiki/Lock%26Stock
|
Lock&Stock is a mobile application in the educational sector intended at helping students by discouraging the use of mobile phones during classes. They aim to reduce the use of cell phones by students and encourage their digital wellbeing by providing rewards and points when they stay off their phones. 67,500 students have currently registered for the app and the total number of time spent offline amounts to over 841 years. The application has 1,181 university partners and has dispersed over AED 3 million scholarships in 2020.
History
The Lock&Stock app was founded in 2017 and is headquartered in Dubai, UAE. Craig Fernandes, a former student at the University of Iowa in the United States founded the Lock&Stock app along with his father Ian Fernandes as co-founder and COO, and with Hussain Ali Asgar, joining as Chief Marketing Officer. It was founded to counter the menace of digital addiction, with students wasting approximately 20% of their time on mobile phones during classes. According to new research from the United Arab Emirates University, almost 30 percent of young Emiratis might be addicted to their phones.
Features
Lock&Stock is a free to use mobile app for students that allows them to earn keys each time their phones are locked. A student earns one key for every minute they are away from their phones. The longer time the student's phone is locked, the more rewards he earns. The app is programmed to only work on campuses. Students can use their rewards to get discounts from brands and to secure scholarships. Once the student leaves the marked radius, they can no longer collect rewards. Lock&Stock recently launched SecureMyScholarship, a website that allows students to secure scholarships from over 1,000 universities.
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https://en.wikipedia.org/wiki/Mrs.%20Met
|
Mrs. Met (previously referred to as Lady Met) is an official mascot of Major League Baseball's New York Mets. She is the female counterpart to Mr. Met and among the oldest of the MLB's mascots.
Origin and early years
Lady Met was introduced by the Mets organization in the mid-1960s, soon after the Mets’ inaugural season. She is one of Major League Baseball's oldest mascots. Like her male counterpart, Lady Met was a human with a large baseball head. Unlike Mr. Met, however, Lady Met had hair. She appeared in print advertisements and pennants in cartoon form, and she also took the form of various toys and trinkets, including small figurines, pins, and cloth dolls. She would sometimes appear with three “little Mets.”
In the 1970s, the Mets organization started referring to Lady Met as Mrs. Met, and she appeared as a live mascot at home games at Shea Stadium. Her head at the time was a plaster-of-paris ball that a character actor would wear around the stadium during the singing of the National Anthem and in the 5th and 7th innings.
Mr. and Mrs. Met were both phased out by the Mets in the 1980s. Mr. Met came back to the team in 1994, but Mrs. Met would remain out of the public eye for some years to come.
Revival
In the early 2000s Mrs. Met re-appeared in the media with a spot on a commercial for the ESPN news show, SportsCenter. Mrs. Met was seen in the front passenger seat of a sports utility vehicle as the Met family left a Mets game. While she spoke to Mr. Met (in subtitles), three little Met children sat in the second row.
The Mets organization reportedly revived Mrs. Met very briefly in 2005. But it wasn't until 2013 that the team brought Mrs. Met back to Queens in earnest. That year, the Mets were set to host the Major League Baseball All-Star Game at Citi Field. A few weeks before the game, the Mets announced that a new Mrs. Met mascot would meet with fans and appear during the All-Star Game festivities. A senior Mets official reported that Mrs. Met h
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https://en.wikipedia.org/wiki/Touschek%20effect
|
The Touschek effect describes the scattering and loss of charged particles in a storage ring. It was discovered by Bruno Touschek.
It is determined by the average of the scattering rate around the ring
In fact, since the momentum acceptance for scattering with energy gain may be different from that for scattering with energy loss, the lifetime must be computed by taking into account the positive and negative momentum acceptances, i.e.
A formula for the local scattering rate, given by Bruck, is
Here, is the classical particle radius, c is the speed of light, N is the number of particles, is the relativistic gamma factor, is the momentum acceptance, are the RMS horizontal, vertical, and bunch sizes, respectively.
where the function F is given by
A more accurate formula, valid in a wider range of conditions is derived by Piwinski.
Momentum acceptance calculation
The standard procedure for computing the momentum acceptance via a tracking code was defined in the paper by Belgroune et al. from the SOLEIL synchrotron.
Calculation in beam dynamics codes
In order to compute the Touschek lifetime for a real storage ring, one needs a beam dynamics code. The Piwinski formula may be used together with the Elegant code for example.
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