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https://en.wikipedia.org/wiki/Advanced%20Amiga%20Architecture%20chipset
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The AAA chipset (Advanced Amiga Architecture) was intended to be the next-generation Amiga multimedia system designed by Commodore International. Initially begun as a secret project, the first design discussions were started in 1988, and after many revisions and redesigns the first silicon versions were fabricated in 1992–1993. The project was stymied in 1993 based on a lack of funds for chip revisions.
At the same time AAA started first silicon testing, the next generation Commodore chipset project was in progress. While AAA was a reinvention and huge upgrade of the Amiga architecture, project Hombre was essentially a clean slate. It took what was learned from Amiga and went in new directions, which included an on-chip CPU with a custom 3D instruction set, 16-bit and 24-bit chunky pixel display, and up to four 16-bit playfields running simultaneously. Hombre also embraced the PCI bus, which was seen as the future for main board interconnect and expansion going forward.
Design goals
AAA was slated to include numerous technologies.
32-bit CPU bus
32-bit and 64-bit graphics bus options.
256 deep CLUT entries 25-bit wide each (256 indirect colors indexed through 24-bit palette with extra genlock bit like AGA has). This mode runs in the native AmigaOS display.
Direct 16 bit-planes planar pixels without CLUT entries, since this mode doesn't contain a palette or a CLUT it requires some kind of ReTargetable Graphics (RTG) driver like chunky modes.
New Agnus/Alice replacement chip 'Andrea' with an updated 32-bit blitter and Copper which can handle chunky pixels.
A line-buffer chip with double buffering called 'Linda' provides higher resolution (up to 1280 x 1024). Linda also decompresses two new packed pixels (PACKLUT, PACKHY) on the fly.
Updated version of Paula called 'Mary' with 8 voices that can be assigned either to left or right channel; each channel has 16-bit resolution with up to 100 kHz sample rate; additionally it does 8-bit audio sampling input.
Dir
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https://en.wikipedia.org/wiki/Acoustic%20location
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Acoustic location is a method of determining the position of an object or sound source by using sound waves. Location can take place in gases (such as the atmosphere), liquids (such as water), and in solids (such as in the earth).
Location can be done actively or passively:
Active acoustic location involves the creation of sound in order to produce an echo, which is then analyzed to determine the location of the object in question.
Passive acoustic location involves the detection of sound or vibration created by the object being detected, which is then analyzed to determine the location of the object in question.
Both of these techniques, when used in water, are known as sonar; passive sonar and active sonar are both widely used.
Acoustic mirrors and dishes, when using microphones, are a means of passive acoustic localization, but when using speakers are a means of active localization. Typically, more than one device is used, and the location is then triangulated between the several devices.
As a military air defense tool, passive acoustic location was used from mid-World War I to the early years of World War II to detect enemy aircraft by picking up the noise of their engines. It was rendered obsolete before and during World War II by the introduction of radar, which was far more effective (but interceptable). Acoustic techniques had the advantage that they could 'see' around corners and over hills, due to sound diffraction.
Civilian uses include locating wildlife and locating the shooting position of a firearm.
Overview
Acoustic source localization is the task of locating a sound source given measurements of the sound field. The sound field can be described using physical quantities like sound pressure and particle velocity. By measuring these properties it is (indirectly) possible to obtain a source direction.
Traditionally sound pressure is measured using microphones. Microphones have a polar pattern describing their sensitivity as a function of the
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https://en.wikipedia.org/wiki/Net%20acid%20excretion
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In renal physiology, net acid excretion (NAE) is the net amount of acid excreted in the urine per unit time. Its value depends on urine flow rate, urine acid concentration, and the concentration of bicarbonate in the urine (the loss of bicarbonate, a buffering agent, is physiologically equivalent to a gain in acid). NAE is commonly expressed in units of milliliters per minute (ml/min) and is given by the following equation:
where
Pathology
Increased net acid excretion is a compensation for respiratory acidosis, while decreased net acid excretion is a compensation for respiratory alkalosis.
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https://en.wikipedia.org/wiki/Chu%20space
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Chu spaces generalize the notion of topological space by dropping the requirements that the set of open sets be closed under union and finite intersection, that the open sets be extensional, and that the membership predicate (of points in open sets) be two-valued. The definition of continuous function remains unchanged other than having to be worded carefully to continue to make sense after these generalizations.
The name is due to Po-Hsiang Chu, who originally constructed a verification of autonomous categories as a graduate student under the direction of Michael Barr in 1979.
Definition
Understood statically, a Chu space (A, r, X) over a set K consists of a set A of points, a set X of states, and a function r : A × X → K. This makes it an A × X matrix with entries drawn from K, or equivalently a K-valued binary relation between A and X (ordinary binary relations being 2-valued).
Understood dynamically, Chu spaces transform in the manner of topological spaces, with A as the set of points, X as the set of open sets, and r as the membership relation between them, where K is the set of all possible degrees of membership of a point in an open set. The counterpart of a continuous function from (A, r, X) to (B, s, Y) is a pair (f, g) of functions f : A → B, g : Y → X satisfying the adjointness condition s(f(a), y) = r(a, g(y)) for all a ∈ A and y ∈ Y. That is, f maps points forwards at the same time as g maps states backwards. The adjointness condition makes g the inverse image function f−1, while the choice of X for the codomain of g corresponds to the requirement for continuous functions that the inverse image of open sets be open. Such a pair is called a Chu transform or morphism of Chu spaces.
A topological space (X, T) where X is the set of points and T the set of open sets, can be understood as a Chu space (X,∈,T) over {0, 1}. That is, the points of the topological space become those of the Chu space while the open sets become states and the membership re
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https://en.wikipedia.org/wiki/Dehn%27s%20lemma
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In mathematics, Dehn's lemma asserts that a piecewise-linear map of a disk into a 3-manifold, with the map's singularity set in the disk's interior, implies the existence of another piecewise-linear map of the disk which is an embedding and is identical to the original on the boundary of the disk.
This theorem was thought to be proven by , but found a gap in the proof. The status of Dehn's lemma remained in doubt until using work by Johansson (1938) proved it using his "tower construction". He also generalized the theorem to the loop theorem and sphere theorem.
Tower construction
Papakyriakopoulos proved Dehn's lemma using a tower of covering spaces. Soon afterwards gave a substantially simpler proof, proving a more powerful result. Their proof used Papakyriakopoulos' tower construction, but with double covers, as follows:
Step 1: Repeatedly take a connected double cover of a regular neighborhood of the image of the disk to produce a tower of spaces, each a connected double cover of the one below it. The map from the disk can be lifted to all stages of this tower. Each double cover simplifies the singularities of the embedding of the disk, so it is only possible to take a finite number of such double covers, and the top level of this tower has no connected double covers.
Step 2. If the 3-manifold has no connected double covers then all its boundary components are 2-spheres. In particular the top level of the tower has this property, and in this case it is easy to modify the map from the disk so that it is an embedding.
Step 3. The embedding of the disk can now be pushed down the tower of double covers one step at a time, by cutting and pasting the 2-disk.
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https://en.wikipedia.org/wiki/Ekman%20layer
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The Ekman layer is the layer in a fluid where there is a force balance between pressure gradient force, Coriolis force and turbulent drag. It was first described by Vagn Walfrid Ekman. Ekman layers occur both in the atmosphere and in the ocean.
There are two types of Ekman layers. The first type occurs at the surface of the ocean and is forced by surface winds, which act as a drag on the surface of the ocean. The second type occurs at the bottom of the atmosphere and ocean, where frictional forces are associated with flow over rough surfaces.
History
Ekman developed the theory of the Ekman layer after Fridtjof Nansen observed that ice drifts at an angle of 20°–40° to the right of the prevailing wind direction while on an Arctic expedition aboard the Fram. Nansen asked his colleague, Vilhelm Bjerknes to set one of his students upon study of the problem. Bjerknes tapped Ekman, who presented his results in 1902 as his doctoral thesis.
Mathematical formulation
The mathematical formulation of the Ekman layer begins by assuming a neutrally stratified fluid, a balance between the forces of pressure gradient, Coriolis and turbulent drag.
where and are the velocities in the and directions, respectively, is the local Coriolis parameter, and is the diffusive eddy viscosity, which can be derived using mixing length theory. Note that is a modified pressure: we have incorporated the hydrostatic of the pressure, to take account of gravity.
There are many regions where an Ekman layer is theoretically plausible; they include the bottom of the atmosphere, near the surface of the earth and ocean, the bottom of the ocean, near the sea floor and at the top of the ocean, near the air-water interface. Different boundary conditions are appropriate for each of these different situations. Each of these situations can be accounted for through the boundary conditions applied to the resulting system of ordinary differential equations. The separate cases of top and bottom boundary l
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https://en.wikipedia.org/wiki/JEIDA%20memory%20card
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The JEIDA memory card standard is a popular memory card standard at the beginning of memory cards appearing on portable computers. JEIDA cards could be used to expand system memory or as a solid-state storage drive.
History
Before the advent of the JEIDA standard, laptops had proprietary cards that were not interoperable with other manufacturers laptops, other laptop lines, or even other models in the same line. The establishment of the JEIDA interface and cards across Japanese portables provoked a response from the US government, through SEMATECH, and thus PCMCIA was born. PCMCIA and JEIDA worked to solve this rift between the two competing standards, and merged into JEIDA 4.1 or PCMCIA 2.0 in 1991.
Usage
The JEIDA memory card was used in earlier ThinkPad models, where IBM branded them as IC DRAM Cards.
The interface has also been used for SRAM cards.
Versions
Version 1.0 is an 88-pin memory card. It has 2 rows of pin holes which are shifted against each other by half the pin spacing. The card is 3.3mm thick.
Version 2.0 is only mechanically compatible with the Version 1.0 card. Version 1.0 cards fail in devices designed for Version 2.0.
Version 3 is a 68-pin memory card. It is also used in the Neo Geo.
Version 4.0 corresponds with 68-pin PCMCIA 1.0 (1990).
Version 4.1 unified the PCMCIA and JEIDA standards as PCMCIA 2.0. v4.1 is the 16-bit PC Card standard that defines Type I, II, III, and IV card sizes.
Version 4.2 is the PCMCIA 2.1 standard, and introduced CardBus' 32-bit interface in an almost physically identical casing.
See also
Japan Electronic Industries Development Association
Japan Electronics and Information Technology Industries Association
Personal Computer Memory Card International Association
Compact Flash
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https://en.wikipedia.org/wiki/Triple-A%20syndrome
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Triple-A syndrome or AAA syndrome is a rare autosomal recessive congenital disorder. In most cases, there is no family history of AAA syndrome. The syndrome was first identified by Jeremy Allgrove and colleagues in 1978; since then just over 100 cases have been reported. The syndrome is called Triple-A due to the manifestation of the illness which includes achalasia (a dysfunction of the esophagus), addisonianism (adrenal insufficiency of primary type), and alacrima (insufficiency of tears). Alacrima is usually the earliest manifestation. Neurodegeneration or atrophy of the nerve cells and autonomic dysfunction may be seen in the disorder; therefore, some have suggested the disorder be called 4A syndrome. It is a progressive disorder that can take years to develop the full-blown clinical picture. The disorder also has variability and heterogeneity in presentation.
Presentation
Individuals affected by AAA have adrenal insufficiency/Addison's disease due to ACTH resistance, alacrima (absence of tear secretion), and achalasia (a failure of a ring of muscle fibers in the lower part of the esophagus to relax) called the lower esophageal sphincter at the cardia (very upper portion of the stomach). The esophagus is the tube that carries food from the mouth to the stomach. Achalasia delays food going to the stomach and causes dilation of the thoracic esophagus. There may also be signs of autonomic dysfunction, such as pupillary abnormalities, an abnormal reaction to intradermal histamine, abnormal sweating, orthostatic hypotension (low blood pressure with standing), and disturbances of the heart rate. Unexplained hypoglycemia (low blood sugar) is often mentioned as an early sign. The disorder has also been associated with mild mental retardation. The syndrome is highly variable. However, one of the most common findings in all patients are the lack of tears. Lack of tears with crying is often mentioned in hindsight after the diagnosis has been made. AAA syndrome may be d
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https://en.wikipedia.org/wiki/Blain%20%28animal%20disease%29
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Blain was an animal disease of unknown etiology that was well known in the 18th and 19th centuries. It is unclear whether it is still extant, or what modern disease it corresponds to.
According to Ephraim Chambers' 18th-century Cyclopaedia, or an Universal Dictionary of Arts and Sciences, blain was "a distemper" (in the archaic eighteenth-century sense of the word, meaning "disease") occurring in animals, consisting of a "Bladder growing on the Root of the Tongue against the Wind-Pipe", which "at length swelling, stops the Wind". It was thought to occur "by great chafing, and heating of the Stomach".
Blain is also mentioned in Cattle: Their Breeds, Management, and Diseases, published in 1836, where it is also identified as "gloss-anthrax". W. C. Spooner's 1888 book The History, Structure, Economy and Diseases of the Sheep also identifies blain as being the same as gloss-anthrax.
A description of blain is provided in the Horticulture column of the Monday Morning edition of the Belfast News-Letter, September 13, 1852. Headline: The Prevailing Epidemic Disease in Horned Cattle - The Mouth and Food Disease. "There are two diseases of the mouth - one of a very serious character, which is called blain (gloss anthrax) or inflammation of the tongue. This is a very virulent disease, and sometimes of a very rapid action, and which should be at once attended to, and not trifled with; but though it always exhibits itself in inflammation of the membranes of the mouth, beneath or above the tongue, and the sides of the tongue itself, it soon extends through the whole system, and, according to the best veterinarians, involves inflammation and gangrene of the oesophagus and intestines. The symptoms are many, the eyes are inflamed, and constantly weeping; swellings appear round the eyes and some other parts of the body; the pulse quick, heaving of the flanks, and the bowels sometimes constipated. Such are the general symptoms of this formidable disease, more or less aggravated by
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https://en.wikipedia.org/wiki/Bench-clearing%20brawl
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A bench-clearing brawl is a form of fighting that occurs in sports, most notably baseball and ice hockey, in which most or all players on both teams leave their dugouts, bullpens, or benches, and charge onto the playing area in order to fight one another or try to break up a fight. Penalties for leaving the bench can range from nothing to severe.
Baseball
In baseball, brawls are usually the result of escalating infractions or indignities, often stemming from a batter being hit by a pitch, especially if the batter then charges the mound. They may also be spurred by an altercation between a baserunner and fielder, such as excessive contact during an attempted tag out.
Few bench-clearing brawls result in serious injury, as in most cases, no punches are thrown, and the action is limited to pushing and shoving. Noteworthy is that players from opposing bullpens run onto the field—often side-by-side, depending on bullpen locations—to join the brawl (which is usually over by the time they arrive), rather than brawling among themselves, highlighting that the purpose of coming onto the field is as a show of support rather than to escalate the conflict.
Unlike most other team sports, in which teams usually have an equivalent number of players on the field at any given time, in baseball the hitting team is at a numerical disadvantage, with a maximum of five players (the batter, up to three runners, and an on-deck batter) and two base coaches on the field at any time, compared to the fielding team's nine players. For this reason, leaving the dugout to join a fight is generally considered acceptable in that it results in numerical equivalence on the field, a fairer fight, and a generally neutral outcome, as in most cases, managers and/or umpires will intervene to restore order and resume the game. In at least one case—the infamous Ten Cent Beer Night promotion—the home team (Cleveland Indians) left their dugout to defend the visiting team (Texas Rangers) from fans who had sto
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https://en.wikipedia.org/wiki/Cre-Lox%20recombination
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Cre-Lox recombination is a site-specific recombinase technology, used to carry out deletions, insertions, translocations and inversions at specific sites in the DNA of cells. It allows the DNA modification to be targeted to a specific cell type or be triggered by a specific external stimulus. It is implemented both in eukaryotic and prokaryotic systems. The Cre-lox recombination system has been particularly useful to help neuroscientists to study the brain in which complex cell types and neural circuits come together to generate cognition and behaviors. NIH Blueprint for Neuroscience Research has created several hundreds of Cre driver mouse lines which are currently used by the worldwide neuroscience community.
An important application of the Cre-lox system is excision of selectable markers in gene replacement. Commonly used gene replacement strategies introduce selectable markers into the genome to facilitate selection of genetic mutations that may cause growth retardation. However, marker expression can have polar effects on the expression of upstream and downstream genes. Removal of selectable markers from the genome by Cre-lox recombination is an elegant and efficient way to circumvent this problem and is therefore widely used in plants, mouse cell lines, yeast, etc.
The system consists of a single enzyme, Cre recombinase, that recombines a pair of short target sequences called the Lox sequences. This system can be implemented without inserting any extra supporting proteins or sequences. The Cre enzyme and the original Lox site called the LoxP sequence are derived from bacteriophage P1.
Placing Lox sequences appropriately allows genes to be activated, repressed, or exchanged for other genes. At a DNA level many types of manipulations can be carried out. The activity of the Cre enzyme can be controlled so that it is expressed in a particular cell type or triggered by an external stimulus like a chemical signal or a heat shock. These targeted DNA changes are us
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https://en.wikipedia.org/wiki/Relation%20algebra
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In mathematics and abstract algebra, a relation algebra is a residuated Boolean algebra expanded with an involution called converse, a unary operation. The motivating example of a relation algebra is the algebra 2 X 2 of all binary relations on a set X, that is, subsets of the cartesian square X2, with R•S interpreted as the usual composition of binary relations R and S, and with the converse of R as the converse relation.
Relation algebra emerged in the 19th-century work of Augustus De Morgan and Charles Peirce, which culminated in the algebraic logic of Ernst Schröder. The equational form of relation algebra treated here was developed by Alfred Tarski and his students, starting in the 1940s. Tarski and Givant (1987) applied relation algebra to a variable-free treatment of axiomatic set theory, with the implication that mathematics founded on set theory could itself be conducted without variables.
Definition
A relation algebra is an algebraic structure equipped with the Boolean operations of conjunction x∧y, disjunction x∨y, and negation x−, the Boolean constants 0 and 1, the relational operations of composition x•y and converse x˘, and the relational constant , such that these operations and constants satisfy certain equations constituting an axiomatization of a calculus of relations. Roughly, a relation algebra is to a system of binary relations on a set containing the empty (0), universal (1), and identity relations and closed under these five operations as a group is to a system of permutations of a set containing the identity permutation and closed under composition and inverse. However, the first-order theory of relation algebras is not complete for such systems of binary relations.
Following Jónsson and Tsinakis (1993) it is convenient to define additional operations x ◁ y = x • y˘, and, dually, x ▷ y = x˘ • y. Jónsson and Tsinakis showed that , and that both were equal to x˘. Hence a relation algebra can equally well be defined a
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https://en.wikipedia.org/wiki/Gene%20dosage
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Gene dosage is the number of copies of a particular gene present in a genome. Gene dosage is related to the amount of gene product (proteins or functional RNAs) the cell is able to express. Since a gene acts as a template, the number of templates in the cell contributes to the amount of gene product able to be produced. However, the amount of gene product produced in a cell is more commonly dependent on regulation of gene expression. The normal gene dosage is dependent on the species; humans generally have two doses -- one copy from the mother and one from the father. Changes in gene dosage can be a result of copy number variation (gene insertions or gene deletions), or aneuploidy (chromosome number abnormalities). These changes can have significant phenotypic consequences.
Ploidy
Ploidy refers to the number of complete sets of chromosomes in a cell.
Humans typically have a gene dosage of two. Because they are diploid, they have two sets of 23 different chromosomes. The number of copies of chromosomes generally correlates to the number of copies of a gene present in the genome. For example, the gene that codes for the beta-subunit of hemoglobin (HBB) is located on chromosome 11. Humans have 2 copies of chromosome 11, so they have 2 copies of the HBB gene.
Because humans are diploid -- getting one copy of each chromosome from either their mother or father -- different alleles can be inherited. Gene dosage can be affected if you present with two different alleles. Such as carriers for sickles cell anemia, who carry one disease allele and one normal allele for hemoglobin. As a result they only produce half normal hemoglobin, and the other half is diseased.
Aneuploidy
If an individual has an abnormal number of chromosomes, then it is called aneuploidy. Aneuploidy is very common in humans, with around 20-40% of all conceptions making a embryo displaying aneuploidy. Most aneuploidy events are fatal and lead to miscarriage. However, there are a few exceptions, inclu
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https://en.wikipedia.org/wiki/Fission%20products%20%28by%20element%29
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This page discusses each of the main elements in the mixture of fission products produced by nuclear fission of the common nuclear fuels uranium and plutonium. The isotopes are listed by element, in order by atomic number.
Neutron capture by the nuclear fuel in nuclear reactors and atomic bombs also produces actinides and transuranium elements (not listed here). These are found mixed with fission products in spent nuclear fuel and nuclear fallout.
Neutron capture by materials of the nuclear reactor (shielding, cladding, etc.) or the environment (seawater, soil, etc.) produces activation products (not listed here). These are found in used nuclear reactors and nuclear fallout. A small but non-negligible proportion of fission events produces not two, but three fission products (not counting neutrons or subatomic particles). This ternary fission usually produces a very light nucleus such as helium (about 80% of ternary fissions produce an alpha particle) or hydrogen (most of the rest produce tritium or to a lesser extent deuterium and protium) as the third product. This is the main source of tritium from light water reactors. Another source of tritium is Helium-6 which immediately decays to (stable) Lithium-6. Lithium-6 produces tritium when hit by neutrons and is one of the main sources of commercially or militarily produced tritium. If the first or only step of nuclear reprocessing is an aqueous solution (as is the case in PUREX) this poses a problem as tritium contamination cannot be removed from water other than by costly isotope separation. Furthermore a tiny fraction of the free neutrons involved in the operation of a nuclear reactor decay to a proton and a beta particle before they can interact with anything else. Given that protons from this source are indistinguishable from protons from ternary fission or radiolysis of coolant water, their overall proportion is hard to quantify.
Germanium-72, 73, 74, 76
If Germanium-75 is produced, it quickly decays to Ars
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https://en.wikipedia.org/wiki/Aberrant%20subclavian%20artery
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Aberrant subclavian artery, or aberrant subclavian artery syndrome, is a rare anatomical variant of the origin of the right or left subclavian artery. This abnormality is the most common congenital vascular anomaly of the aortic arch, occurring in approximately 1% of individuals.
Presentation
This condition is usually asymptomatic. The aberrant artery usually arises just distal to the left subclavian artery and crosses in the posterior part of the mediastinum on its way to the right upper extremity. In 80% of individuals it crosses behind the esophagus. Such course of this aberrant vessel may cause a vascular ring around the trachea and esophagus.
Dysphagia due to an aberrant right subclavian artery is termed dysphagia lusoria, although this is a rare complication. In addition to dysphagia, aberrant right subclavian artery may cause stridor, dyspnoea, chest pain, or fever. An aberrant right subclavian artery may compress the recurrent laryngeal nerve causing a palsy of that nerve, which is termed Ortner's syndrome.
The aberrant right subclavian artery frequently arises from a dilated segment of the proximal descending aorta, the so-called Diverticulum of Kommerell (which was named for the German radiologist Burkhard Friedrich Kommerell (1901–1990), who discovered it in 1936). It is alternatively known as a lusorian artery.
Pathophysiology
In the normal embryological development of the aortic arches, the right dorsal aorta regresses caudal to the origin of the 7th intersegmental artery which gives rise to the right subclavian artery. In formation of an aberrant right subclavian artery, the regression occurs instead between the 7th intersegmental artery and the right common carotid so that the right subclavian artery is then connected to the left dorsal aorta via the part of the right dorsal aorta which normally regresses. During growth, the origin of the right subclavian artery migrates until it is just distal to that of the left subclavian.
Diagnosis
Treatmen
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https://en.wikipedia.org/wiki/Horticultural%20therapy
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Horticultural therapy (also known as garden therapy or social and therapeutic horticulture or STH) is defined by the American Horticultural Therapy Association (AHTA) as the engagement of a person in gardening and plant-based activities, facilitated by a trained therapist, to achieve specific therapeutic treatment goals. Direct contact with plants is believed to guide a person's focus away from stress enhancing their overall quality of life. The AHTA believes that horticultural therapy is an active process which occurs in the context of an established treatment plan. Horticultural therapists are specially educated and trained members of rehabilitation teams (with doctors, psychiatrists, psychologists, occupational therapists and others) who involve the client in all phases of gardening, from propagation to selling products, as a means of bringing about improvement in their life.
History
The use of horticulture to calm the senses dates as far back as 2000 BC in ancient Mesopotamia, and around 500 BC, ancient Persians created gardens to soothe the senses by involving beauty, fragrance, flowing water, and cool temperatures. According to the American Horticultural Therapy Association, Ancient Egyptian physicians prescribed walks around a garden for patients with mental illness; which makes the first sign of the therapeutic process in Alexandria and Ancient Egypt through Renaissance Europe. During the Middle Ages, on the grounds of a monastery hospital, plants were used to express purpose of cheering up melancholy patients. Also, the gardens were used to treat both physical and mental ailments of sickness who visited them. The first modern documentation of horticulture being used as a treatment for mental health purposes was in the 1800s. Dr. Benjamin Rush was the first to suggest that field labor in a farm setting helped attain positive outcomes for clients with mental illness This discovery lead many hospitals in the western world to begin using horticulture as a m
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https://en.wikipedia.org/wiki/CellProfiler
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CellProfiler is free, open-source software designed to enable biologists without training in computer vision or programming to quantitatively measure phenotypes from thousands of images automatically. Advanced algorithms for image analysis are available as individual modules that can be placed in sequential order together to form a pipeline; the pipeline is then used to identify and measure
biological objects and features in images, particularly those obtained through fluorescence microscopy.
Distributions are available for Microsoft Windows, macOS, and Linux. The source code for CellProfiler is freely available. CellProfiler is developed by the Broad Institute's Imaging Platform.
Features
CellProfiler can read and analyze most common microscopy image formats. Biologists typically use CellProfiler to identify objects of interest (e.g. cells, colonies, C. elegans worms) and then measure their properties of interest. Specialized modules for illumination correction may be applied as pre-processing step to remove distortions due to uneven lighting. Object identification (segmentation) is performed through machine learning or image thresholding, recognition and division of clumped objects, and removal or merging of objects on the basis of size or shape. Each of these steps are customizable by the user for their unique image assay.
A wide variety of measurements can be generated for each identified cell or subcellular compartment, including morphology, intensity, and texture among others. These measurements are accessible by using built-in viewing and plotting data tools, exporting in a comma-delimited spreadsheet format, or importing into a MySQL or SQLite database.
CellProfiler interfaces with the high-performance scientific libraries NumPy and SciPy for many mathematical operations, the Open Microscopy Environment Consortium’s Bio-Formats library for reading more than 100 image file formats, ImageJ for use of plugins and macros, and ilastik for pixel-based classif
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https://en.wikipedia.org/wiki/Interosseous%20talocalcaneal%20ligament
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The interosseous talocalcaneal ligament forms the chief bond of union between the talus and calcaneus.
It is a portion of the united capsules of the talocalcaneonavicular and the talocalcaneal joints, and consists of two partially united layers of fibers, one belonging to the former and the other to the latter joint.
It is attached, above, to the groove between the articular facets of the under surface of the talus; below, to a corresponding depression on the upper surface of the calcaneus.
It is very thick and strong, being at least 2.5 cm. in breadth from side to side, and serves to bind the calcaneus and talus firmly together.
See also
Subtalar joint
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https://en.wikipedia.org/wiki/Anterior%20talocalcaneal%20ligament
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The anterior talocalcaneal ligament (anterior calcaneo-astragaloid ligament or anterior interosseous ligament) is a ligament in the foot.
The anterior talocalcaneal ligament extends from the front and lateral surface of the neck of the talus to the sinus tarsi of the calcaneus.
It forms the posterior boundary of the talocalcaneonavicular joint.
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https://en.wikipedia.org/wiki/Lateral%20talocalcaneal%20ligament
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The lateral talocalcaneal ligament (external calcaneo-astragaloid ligament) is a ligament in the ankle. It is a short, strong fasciculus, passing from the lateral surface of the talus, immediately beneath its fibular facet to the lateral surface of the calcaneus.
It is placed in front of, but on a deeper plane than, the calcaneofibular ligament, with the fibers of which it is parallel.
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https://en.wikipedia.org/wiki/Posterior%20talocalcaneal%20ligament
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The posterior talocalcaneal ligament (posterior calcaneo-astragaloid ligament) connects the lateral tubercle of the talus with the upper and medial part of the calcaneus; it is a short band, and its fibers radiate from their narrow attachment to the talus.
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https://en.wikipedia.org/wiki/Medial%20talocalcaneal%20ligament
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The medial talocalcaneal ligament (internal calcaneo-astragaloid ligament) connects the medial tubercle of the back of the talus with the back of the sustentaculum tali.
Its fibers blend with those of the plantar calcaneonavicular ligament.
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https://en.wikipedia.org/wiki/Calcaneofibular%20ligament
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The calcaneofibular ligament is a narrow, rounded cord, running from the tip of the lateral malleolus of the fibula downward and slightly backward to a tubercle on the lateral surface of the calcaneus. It is part of the lateral collateral ligament, which opposes the hyperinversion of the subtalar joint, as in a common type of ankle sprain.
It is covered by the tendons of the fibularis longus and brevis muscles.
Clinical significance
The calcaneofibular ligament is commonly sprained ligament in ankle injuries. It may be injured individually, or in combination with other ligaments such as the anterior talofibular ligament and the posterior talofibular ligament.
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https://en.wikipedia.org/wiki/Lov%C3%A1sz%20conjecture
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In graph theory, the Lovász conjecture (1969) is a classical problem on Hamiltonian paths in graphs. It says:
Every finite connected vertex-transitive graph contains a Hamiltonian path.
Originally László Lovász stated the problem in the opposite way, but
this version became standard. In 1996, László Babai published a conjecture sharply contradicting this conjecture, but both conjectures remain widely open. It is not even known if a single counterexample would necessarily lead to a series of counterexamples.
Historical remarks
The problem of finding Hamiltonian paths in highly symmetric graphs is quite old. As Donald Knuth describes it in volume 4 of The Art of Computer Programming, the problem originated in British campanology (bell-ringing). Such Hamiltonian paths and cycles are also closely connected to Gray codes. In each case the constructions are explicit.
Variants of the Lovász conjecture
Hamiltonian cycle
Another version of Lovász conjecture states that
Every finite connected vertex-transitive graph contains a Hamiltonian cycle except the five known counterexamples.
There are 5 known examples of vertex-transitive graphs with no Hamiltonian cycles (but with Hamiltonian paths): the complete graph , the Petersen graph, the Coxeter graph and two graphs derived from the Petersen and Coxeter graphs by replacing each vertex with a triangle.
Cayley graphs
None of the 5 vertex-transitive graphs with no Hamiltonian cycles is a Cayley graph. This observation leads to a weaker version of the conjecture:
Every finite connected Cayley graph contains a Hamiltonian cycle.
The advantage of the Cayley graph formulation is that such graphs correspond to a finite group and a
generating set . Thus one can ask for which and the conjecture holds rather than attack it in full generality.
Directed Cayley graph
For directed Cayley graphs (digraphs) the Lovász conjecture is false. Various counterexamples were obtained by Robert Alexander Rankin. Still, many of the belo
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https://en.wikipedia.org/wiki/Epoxyeicosatrienoic%20acid
|
The epoxyeicosatrienoic acids or EETs are signaling molecules formed within various types of cells by the metabolism of arachidonic acid by a specific subset of Cytochrome P450 enzymes termed cytochrome P450 epoxygenases. These nonclassic eicosanoids are generally short-lived, being rapidly converted from epoxides to less active or inactive dihydroxy-eicosatrienoic acids (diHETrEs) by a widely distributed cellular enzyme, Soluble epoxide hydrolase (sEH), also termed Epoxide hydrolase 2. The EETs consequently function as transiently acting, short-range hormones; that is, they work locally to regulate the function of the cells that produce them (i.e. they are autocrine agents) or of nearby cells (i.e. they are paracrine agents). The EETs have been most studied in animal models where they show the ability to lower blood pressure possibly by a) stimulating arterial vasorelaxation and b) inhibiting the kidney's retention of salts and water to decrease intravascular blood volume. In these models, EETs prevent arterial occlusive diseases such as heart attacks and brain strokes not only by their anti-hypertension action but possibly also by their anti-inflammatory effects on blood vessels, their inhibition of platelet activation and thereby blood clotting, and/or their promotion of pro-fibrinolytic removal of blood clots. With respect to their effects on the heart, the EETs are often termed cardio-protective. Beyond these cardiovascular actions that may prevent various cardiovascular diseases, studies have implicated the EETs in the pathological growth of certain types of cancer and in the physiological and possibly pathological perception of neuropathic pain. While studies to date imply that the EETs, EET-forming epoxygenases, and EET-inactivating sEH can be manipulated to control a wide range of human diseases, clinical studies have yet to prove this. Determination of the role of the EETS in human diseases is made particularly difficult because of the large number of
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https://en.wikipedia.org/wiki/International%20Joint%20Conference%20on%20Automated%20Reasoning
|
The International Joint Conference on Automated Reasoning (IJCAR) is a series of conferences on the topics of automated reasoning, automated deduction, and related fields. It is organized semi-regularly as a merger of other meetings. IJCAR replaces those independent conferences in the years it takes place. The conference is organized by CADE Inc., and CADE has always been one of the conferences partaking in IJCAR.
The first IJCAR was held in Siena, Italy in 2001 as a merger of CADE, FTP, and TABLEAUX.
The second IJCAR was held in Cork, Ireland in 2004 as a merger of CADE, FTP, TABLEAUX, FroCoS and CALCULEMUS.
The third IJCAR was held as an independent subconference of the fourth Federated Logic Conference in Seattle, United States, and merged CADE, FTP, TABLEAUX, FroCoS and TPHOLs.
The fourth IJCAR was held in Sydney, Australia in 2008, and merged CADE, FroCoS, FTP and TABLEAUX.
The fifth IJCAR was held in 2010 as an independent subconference of the fifth Federated Logic Conference in Edinburgh, UK, and merged CADE, FTP, TABLEAUX, and FroCoS.
The sixth IJCAR was held in Manchester, UK, as part of the Alan Turing Year 2012, and was collocated with the Alan Turing Centenary Conference. It again merged CADE, FTP, TABLEAUX, and FroCoS.
The seventh IJCAR was held in Vienna, Austria, as part of the Vienna Summer of Logic in 2014, and merged CADE, TABLEAUX, and FroCoS.
The eighth IJCAR was held in Coimbra, Portugal, in 2016, and merged CADE, TABLEAUX, and FroCoS.
External links
IJCAR Home Page
IJCAR-2006 Home Page
IJCAR-2008 Home Page
IJCAR 2016 Home Page
Theoretical computer science conferences
Logic conferences
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https://en.wikipedia.org/wiki/Marshall%20Fredericks
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Marshall Maynard Fredericks (January 31, 1908 – April 4, 1998) was an American sculptor known for such works as Fountain of Eternal Life, The Spirit of Detroit, Man and the Expanding Universe Fountain, and many others.
Early life and education
Fredericks was born of Scandinavian descent in Rock Island, Illinois, on January 31, 1908. His family moved to Florida for a short time and then settled in Cleveland, where he grew-up. He graduated from the Cleveland School of Art in 1930 and journeyed abroad on a fellowship to study with Carl Milles (1875–1955) in Sweden. After some months he studied in other academies and private studios in Denmark, Germany, France, and Italy, and traveled extensively in Europe and North Africa.
In 1932, Milles invited him to join the staffs of Cranbrook Academy of Art and Cranbrook and Kingswood School in Bloomfield Hills, Michigan, where he taught until he enlisted in the armed forces in 1942. In 1945, Fredericks was honorably discharged from the Air Force as a lieutenant colonel.
Career
In 1936, Fredericks won a competition to create the Levi L. Barbour Memorial Fountain on Belle Isle in Detroit. This was to be the first of many public monuments created by Fredericks. After World War II, the sculptor worked continuously on his numerous commissions for fountains, memorials, free-standing sculptures, reliefs, and portraits in bronze and other materials. Many of his works have spiritual intensity, lighthearted humor and a warm and gentle humanist spirit like that found in Fredericks himself.
Fredericks was the recipient of many American and foreign awards and decorations for his artistic and humanitarian achievements. He exhibited his work nationally and internationally and many of his works are in national, civic, and private collections. In 1957, he was elected into the National Academy of Design as an Associate member, and became a full Academician in 1961.
He resided in Birmingham, Michigan, with his wife Rosalind Cooke until his de
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https://en.wikipedia.org/wiki/Timeline%20of%20heat%20engine%20technology
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This timeline of heat engine technology describes how heat engines have been known since antiquity but have been made into increasingly useful devices since the 17th century as a better understanding of the processes involved was gained. A heat engine is any system that converts heat to mechanical energy, which can then be used to do mechanical work.They continue to be developed today.
In engineering and thermodynamics, a heat engine performs the conversion of heat energy to mechanical work by exploiting the temperature gradient between a hot "source" and a cold "sink". Heat is transferred to the sink from the source, and in this process some of the heat is converted into work.
A heat pump is a heat engine run in reverse. Work is used to create a heat differential. The timeline includes devices classed as both engines and pumps, as well as identifying significant leaps in human understanding.
Pre-17th century
Prehistory – The fire piston used by tribes in southeast Asia and the Pacific islands to kindle fire.
c. 450 BC – Archytas of Tarentum used a jet of steam to propel a toy wooden bird suspended on wire.
c. 50 AD – Hero of Alexandria's Engine, also known as Aeolipile. Demonstrates rotary motion produced by the reaction from jets of steam.
c. 10th century – China develops the earliest fire lances which were spear-like weapons combining a bamboo tube containing gunpowder and shrapnel like projectiles tied to a spear.
c 12th century – China, the earliest depiction of a gun showing a metal body and a tight-fitting projectile which maximises the conversion of the hot gases to forward motion.
1125 – Gerbert, a professor in the schools at Rheims designed and built an organ blown by air escaping from a vessel in which it was compressed by heated water.
1232 – First recorded use of a rocket. In a battle between the Chinese and the Mongols. ( see Timeline of rocket and missile technology for a view of rocket development through time.)
c. 1500 – Leonardo da Vinc
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https://en.wikipedia.org/wiki/Offshoot%20%28plant%29
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Offshoots are lateral shoots that are produced on the main stem of a plant. They may be known colloquially as "suckers", “pups” or “sister plants”
See also
Stolon or runners
Plant anatomy
Plant morphology
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https://en.wikipedia.org/wiki/Field%20specification
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A field specification or fspec defines a portion of a word in some programming language. It has the form "(L:R)" where "L" is the leftmost byte and "R" is the rightmost byte, and counting begins at zero. For example, the first three bytes of a word would have the fspec (0:2) for bytes numbered 0, 1, and 2.
Units of information
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https://en.wikipedia.org/wiki/Lepton%20epoch
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In cosmological models of the Big Bang, the lepton epoch was the period in the evolution of the early universe in which the leptons dominated the mass of the Universe. It started roughly 1 second after the Big Bang, after the majority of hadrons and anti-hadrons annihilated each other at the end of the hadron epoch. During the lepton epoch, the temperature of the Universe was still high enough to create neutrino and electron-positron pairs. Approximately 10 seconds after the Big Bang, the temperature of the universe had fallen to the point where electron-positron pairs were gradually annihilated. A small residue of electrons needed to charge-neutralize the Universe remained along with free streaming neutrinos: an important aspect of this epoch is the neutrino decoupling. The Big Bang nucleosynthesis epoch follows, overlapping with the photon epoch.
See also
Timeline of the early universe
Chronology of the universe
Cosmology
Big Bang
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https://en.wikipedia.org/wiki/Electroweak%20epoch
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In physical cosmology, the electroweak epoch was the period in the evolution of the early universe when the temperature of the universe had fallen enough that the strong force separated from the electroweak interaction, but was high enough for electromagnetism and the weak interaction to remain merged into a single electroweak interaction above the critical temperature for electroweak symmetry breaking (159.5±1.5 GeV
in the Standard Model of particle physics). Some cosmologists place the electroweak epoch at the start of the inflationary epoch, approximately 10−36 seconds after the Big Bang. Others place it at approximately 10−32 seconds after the Big Bang when the potential energy of the inflaton field that had driven the inflation of the universe during the inflationary epoch was released, filling the universe with a dense, hot quark–gluon plasma. Particle interactions in this phase were energetic enough to create large numbers of exotic particles, including W and Z bosons and Higgs bosons. As the universe expanded and cooled, interactions became less energetic and when the universe was about 10−12 seconds old, W and Z bosons ceased to be created at observable rates. The remaining W and Z bosons decayed quickly, and the weak interaction became a short-range force in the following quark epoch.
The electroweak epoch ended with an electroweak phase transition, the nature of which is unknown. If first order, this could source a gravitational wave background. The electroweak phase transition is also a potential source of baryogenesis, provided the Sakharov conditions are satisfied.
In the minimal Standard Model, the transition during the electroweak epoch was not a first- or a second-order phase transition but a continuous crossover, preventing any baryogenesis,
or the production of an observable gravitational wave background.
However many extensions to the Standard Model including supersymmetry and the two-Higgs-doublet model have a first-order electroweak phase tr
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https://en.wikipedia.org/wiki/Grand%20unification%20epoch
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In physical cosmology, assuming that nature is described by a Grand Unified Theory, the grand unification epoch was the period in the evolution of the early universe following the Planck epoch, starting at about 10−43 seconds after the Big Bang, in which the temperature of the universe was comparable to the characteristic temperatures of grand unified theories. If the grand unification energy is taken to be 1015 GeV, this corresponds to temperatures higher than 1027 K. During this period, three of the four fundamental interactions — electromagnetism, the strong interaction, and the weak interaction — were unified as the electronuclear force. Gravity had separated from the electronuclear force at the end of the Planck era. During the grand unification epoch, physical characteristics such as mass, charge, flavour and colour charge were meaningless.
The grand unification epoch ended at approximately 10−36 seconds after the Big Bang. At this point several key events took place. The strong force separated from the other fundamental forces.
It is possible that some part of this decay process violated the conservation of baryon number and gave rise to a small excess of matter over antimatter (see baryogenesis). This phase transition is also thought to have triggered the process of cosmic inflation that dominated the development of the universe during the following inflationary epoch.
See also
Big Bang
Chronology of the universe
Ultimate fate of the universe
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https://en.wikipedia.org/wiki/Fierz%20identity
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In theoretical physics, a Fierz identity is an identity that allows one to rewrite bilinears of the product of two spinors as a linear combination of products of the bilinears of the individual spinors. It is named after Swiss physicist Markus Fierz. The Fierz identities are also sometimes called the Fierz–Pauli–Kofink identities, as Pauli and Kofink described a general mechanism for producing such identities.
There is a version of the Fierz identities for Dirac spinors and there is another version for Weyl spinors. And there are versions for other dimensions besides 3+1 dimensions. Spinor bilinears in arbitrary dimensions are elements of a Clifford algebra; the Fierz identities can be obtained by expressing the Clifford algebra as a quotient of the exterior algebra.
When working in 4 spacetime dimensions the bivector may be decomposed in terms of the Dirac matrices that span the space:
.
The coefficients are
and are usually determined by using the orthogonality of the basis under the trace operation. By sandwiching the above decomposition between the desired gamma structures, the identities for the contraction of two Dirac bilinears of the same type can be written with coefficients according to the following table.
{| class="wikitable" style="text-align: center"
|-
! Product
! S
! V
! T
! A
! P
|-
| S × S =
| 1/4
| 1/4
| −1/4
| −1/4
| 1/4
|-
| V × V =
| 1
| −1/2
| 0
| −1/2
| −1
|-
| T × T =
| −3/2
| 0
| −1/2
| 0
| −3/2
|-
| A × A =
| −1
| −1/2
| 0
| −1/2
| 1
|-
| P × P =
| 1/4
| −1/4
| −1/4
| 1/4
| 1/4
|-
|}
where
The table is symmetric with respect to reflection across the central element.
The signs in the table correspond to the case of commuting spinors, otherwise, as is the case of fermions in physics, all coefficients change signs.
For example, under the assumption of commuting spinors, the V × V product can be expanded as,
Combinations of bilinears corresponding to the eigenvectors of the transpose matrix tra
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https://en.wikipedia.org/wiki/AES52
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AES52 is a standard first published by the Audio Engineering Society in March 2006 that specifies the insertion of unique identifiers into the AES3 digital audio transport structure.
Background
The AES3 transport stream continues to be used extensively in both discrete and network based audio systems alongside audio stored as files. Audio content is moving towards being handled by asset management systems and descriptive metadata is associated with that content is also being stored within systems. In order to provide a mechanism for AES3 transport streams to have similar abilities to work with content management systems, some form of unique label is required which can provide the link with these systems. One of the unique labels currently standardised in the media industry is the SMPTE UMID (SMPTE 330M-2004) while another commonly used in the Information Technology area is the International Electrotechnical Commission (IEC) UUID.
Operation
The standard specifies the method for inserting unique identifiers into the user data area of an AES3 stream. This specifically covers the use of UUID as well as a basic or extended SMPTE UMID but can be extended to embed other data types into the AES3 stream by registering these with the AES so the standard can be updated to include these by following AES due process.
External links
AES52-2006 from the AES standards web site
Audio engineering
Audio Engineering Society standards
Unique identifiers
Broadcasting standards
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https://en.wikipedia.org/wiki/Pelado
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In Mexican society, pelado is "a term said to have been invented to describe a certain class of urban 'bum' in Mexico in the 1920s."
It was used, however, much earlier. Lewis Garrard used it in his book, "Wah-to-yah and the Taos Trail," his first-hand account of crossing the Plains to Taos, published in 1850. He wrote: "This hos has feelin's hyar," slapping his breast, "for poor human natur in any fix, but for these palous (pelados) he doesn't care a cuss."
Historical background
Mexico has a long tradition of urban poverty, beginning with the léperos, a term referring to shiftless vagrants of various racial categories in the colonial hierarchical racial system, the sociedad de castas. They included mestizos, natives, and poor whites (españoles). Léperos were viewed as unrespectable people (el pueblo bajo) by polite society (la gente culta), who judged them as being morally and biologically inferior.
Léperos supported themselves as they could through petty commerce or begging, but many resorted to crime. A study of crime in eighteenth-century Mexico City based on arrest records indicates that they were "neither marginal types nor dregs of the lower classes. They consisted of both men and women; they were not particularly young; they were not mainly single and rootless; they were not merely Indian and casta; and they were not largely unskilled." None of the popular stereotypes of a young rootless, unskilled male is borne out by the arrest records. "The dangerous class existed only in the collective mind of the colonial elite."
They established a thieves' market across from the viceregal palace, which was later moved to the Tepito area of the working-class Colonia Guerrero. They spent much of their time in taverns, leading to the official promotion of theater as an alternative.
Initially, many of these plays were organized by the church, but the people soon set up their own theaters, where the humor of the taverns survived. The rowdy, often illegal stagings were
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https://en.wikipedia.org/wiki/Vine%20Linux
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is a Japanese Linux distribution sponsored by VineCaves. It has been a fork of Red Hat Linux 7.2 since Vine Linux 3.0. Work on Vine Linux was started in 1998.
All versions except Vine Seed have been announced to be discontinued from May 4, 2021.
Release history
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https://en.wikipedia.org/wiki/Unique%20Material%20Identifier
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The Unique Material Identifier (UMID) is a SMPTE standard for providing a stand-alone method for generating a unique label designed to be used to attach to media files and streams. The UMID is standardized in SMPTE 330M.
There are two types of UMID:
Basic UMID
contains the minimal components necessary for the unique identification (the essential metadata) The length of the basic UMID is 32 octets.
The Extended UMID
provides information on the creation time and date, recording location and the name of the organisation and the maker as well as the components of the Basic UMID. The length of the Extended UMID is 64 octets. This data may be parsed to extract specific information produced at the time it was generated or simply used as a unique label.
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https://en.wikipedia.org/wiki/Microtuner
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A microtuner or microtonal tuner is an electronic device or software program designed to modify and test the tuning of musical instruments (in particular synthesizers) with microtonal precision, allowing for the design and construction of microtonal scales and just intonation scales, and for tuning intervals that may differ from those of common Western equal temperament. The term also indicates a high-precision mechanical tuning device found on some vintage Conn brand brass and reed instruments (mostly cornets and alto saxophones). These were first introduced with their 1918 catalog and manufactured until about 1954. Such devices were also offered with some vintage saxophones manufactured in Europe by Beaugnier, Dolnet, Hüller, Keilwerth and other famous makers in the same period.
See also
Computer music
Electronic tuner
Microtonal music
MIDI Tuning Standard
Musical tuning
Scala (program)
Tuner (disambiguation)
Tuning (disambiguation)
Electronic music
Microtonality
Musical tuning
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https://en.wikipedia.org/wiki/Tiger%20bush
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Tiger bush, or brousse tigrée in the French language, is a patterned vegetation community and ground consisting of alternating bands of trees, shrubs, or grass separated by bare ground or low herb cover, that run roughly parallel to contour lines of equal elevation. The patterns occur on low slopes in arid and semi-arid regions, such as in Australia, Sahelian West Africa, and North America.
Due to the natural water harvesting capacity, many species in tiger bush usually occur only under a higher rainfall regime.
Formation
The alternating pattern arises from the interplay of hydrological, ecological, and erosional phenomena. In the regions where tiger bush is present, plant growth is water-limited - the shortage of rainfall prevents vegetation from covering the entire landscape. Instead, trees and shrubs are able to establish by either tapping soil moisture reserves laterally or by sending roots to deeper, wetter soil depths. By a combination of plant litter, root macropores, and increased surface roughness, infiltration into the soil around the base of these plants is enhanced. Surface runoff arriving at these plants will thus likely to become run-on, and infiltrate into the soil.
By contrast, the areas between these larger plants contain a greater portion of bare ground and herbaceous plants. Both bare soil, with its smoother surface and soil crusts, and herbaceous plants, with fewer macropores, inhibit infiltration. This causes much of the rainfall that falls in the inter-canopy areas to flow downslope, and infiltrate beneath the larger plants. The larger plants are in effect harvesting rainfall from the ground immediately up-slope.
Although these vegetation patterns may seem very stable through time, such patterning requires specific climatic conditions. For instance, a decrease in rainfall is able to trigger patterning in formerly homogeneous vegetation within a few decades.
More water will infiltrate at the up-slope edge of the canopies than down-slope. T
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https://en.wikipedia.org/wiki/Patterned%20vegetation
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Patterned vegetation is a vegetation community that exhibits distinctive and repetitive patterns. Examples of patterned vegetation include fir waves, tiger bush, and string bog. The patterns typically arise from an interplay of phenomena that differentially encourage plant growth or mortality. A coherent pattern arises because there is a strong directional component to these phenomena, such as wind in the case of fir waves, or surface runoff in the case of tiger bush.
The regular patterning of some types of vegetation is a striking feature of some landscapes. Patterns can include relatively evenly spaced patches, parallel bands or some intermediate between those two. These patterns in the vegetation can appear without any underlying pattern in soil types, and are thus said to “self-organize” rather than be determined by the environment.
Several of the mechanisms underlying patterning of vegetation have been known and studied since at least the middle of the 20th century, however, mathematical models replicating them have only been produced much more recently. Self-organization in spatial patterns is often a result of spatially uniform states becoming unstable through the monotonic growth and amplification of nonuniform perturbations. A well known instability of this kind leads to so-called Turing patterns. These patterns occur at many scales of life, from cellular development (where they were first proposed) to pattern formation on animal pelts to sand dunes and patterned landscapes (see also pattern formation). In their simplest form models that capture Turing instabilities require two interactions at differing scales: local facilitation and more distant competition. For example, when Sato and Iwasa produced a simple model of fir waves in the Japanese Alps, they assumed that trees exposed to cold winds would suffer mortality from frost damage, but upwind trees would protect nearby downwind trees from wind. Banding appears because the protective boundary layer crea
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https://en.wikipedia.org/wiki/Anatomically%20correct%20doll
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An anatomically correct doll or anatomically precise doll is a doll that depicts some of the primary and secondary sex characteristics of a human for educational purposes. A very detailed type of anatomically correct doll may be used in questioning children who may have been sexually abused. The use of dolls as interview aids has been criticized, and the validity of information obtained this way has been contested.
Overview
Some children's baby dolls and potty training dolls are anatomically correct for educational purposes. There are also dolls that are used as medical models, particularly in explaining medical procedures to child patients. These have a more detailed depiction of the human anatomy and may include features like removable internal organs. One notable anatomically correct doll was the "Archie Bunker's Grandson Joey Stivic" doll that was made by the Ideal Toy Co. in 1976. The doll, which was modeled after infant character Joey Stivic from the Television sitcom series All In The Family, was considered to be the first anatomically correct boy doll.
The dolls are also sometimes used by parents or teachers as sex education.
Forensic use
A particular type of anatomically correct dolls are used in law enforcement and therapy. These dolls have detailed depictions of all the primary and secondary sexual characteristics of a human: "oral and anal openings, ears, tongues, nipples, and hands with individual fingers" for all and a "vagina, clitoris and breasts" for each of the female dolls and a "penis and testicles" for each of the male dolls.
These dolls are used during interviews with children who may have been sexually abused. The dolls wear removable clothing, and the anatomically correct and similarly scaled body parts ensure that sexual activity can be simulated realistically.
There is some criticism with regard to using anatomically correct dolls to question victims of sexual abuse. Critics argue that because of the novelty of the dolls, children wil
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https://en.wikipedia.org/wiki/3T3%20cells
|
3T3 cells are several cell lines of mouse embryonic fibroblasts. The original 3T3 cell line (3T3-Swiss albino) was established in 1962 by two scientists then at the Department of Pathology in the New York University School of Medicine, George Todaro and Howard Green. Todaro and Green originally obtained their 3T3 cells from Swiss albino mouse embryo tissue. Later, as a principal investigator position at the National Cancer Institute in Bethesda, Maryland, Todaro repeated the isolation procedure from the NIH Swiss mouse embryo with his students and established NIH-3T3 cell line.
Nomenclature
The '3T3' designation refers to the abbreviation of "3-day transfer, inoculum cells." This cell line was originally established from the primary mouse embryonic fibroblast cells that were cultured by the designated protocol, so-called '3T3 protocol'. The primary mouse embryonic fibroblast cells were transferred (the "T") every 3 days (the first "3"), and inoculated at the rigid density of cells per 20 cm2 dish (the second "3") continuously. The spontaneously immortalized cells with stable growth rate were established after 20 to 30 generations in culture, and then named '3T3' cells. Since then, several cell lines have been established with this procotol:
3T3-Swiss albino, the original 1962 cell line
3T3-J2, a subclone of 3T3-Swiss albino, commonly used as feeders for keratinocyte cultures
3T3-L1, a subclone of 3T3-Swiss albino, used as a model of adipogenesis
NIH-3T3, also from Swiss albino mice
BALB/c-3T3 clone A31, from BALB/c mice
Characteristics
Swiss 3T3 can be inhibited by temazepam and other benzodiazepines. These cells are also contact inhibited. The cells are sensitive to sarcoma virus and leukemia virus focus formation. 3T3 cells can be transformed with SV40 and some other polyomaviruses.
Culture characteristics
Adherent cells grow as a monolayer. A confluent monolayer yields 40000 cells/cm2.
Expression
Lysophosphatidylcholine (lyso-PC) induces AP-1 activity a
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https://en.wikipedia.org/wiki/Signor%E2%80%93Lipps%20effect
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The Signor–Lipps effect is a paleontological principle proposed in 1982 by Philip W. Signor and Jere H. Lipps which states that, since the fossil record of organisms is never complete, neither the first nor the last organism in a given taxon will be recorded as a fossil. The Signor–Lipps effect is often applied specifically to cases of the youngest-known fossils of a taxon failing to represent the last appearance of an organism. The inverse, regarding the oldest-known fossils failing to represent the first appearance of a taxon, is alternatively called the Jaanusson effect after researcher Valdar Jaanusson, or the Sppil–Rongis effect (Signor–Lipps spelled backwards).
One famous example is the coelacanth, which was thought to have become extinct in the very late Cretaceous—until a live specimen was caught in 1938. The animals known as "Burgess Shale-type fauna" are best known from rocks of the Early and Middle Cambrian periods. Since 2006, though, a few fossils of similar animals have been found in rocks from the Ordovician, Silurian, and Early Devonian periods, in other words up to 100 million years after the Burgess Shale. The particular way in which such animals have been fossilized may depend on types of ocean chemistry that were present for limited periods of time.
But the Signor–Lipps effect is more important for the difficulties it raises in paleontology:
It makes it very difficult to be confident about the timing and speed of mass extinctions, and this makes it difficult to test theories about the causes of mass extinctions. For example, the extinction of the dinosaurs was long thought to be a gradual process, but evidence collected since the late 1980s suggests it was abrupt, which is consistent with the idea that an asteroid impact caused it.
The uncertainty about when a taxon first appeared makes it difficult to be confident about the ancestry of specific genera. For example, if the earliest-known fossil of genus X is much earlier than the earliest-kno
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https://en.wikipedia.org/wiki/Edgar%20Zilsel
|
Edgar Zilsel (August 11, 1891, Vienna, Austria-Hungary – March 11, 1944, Oakland, California) was an Austrian-American historian and philosopher of science.
He is best known for the Zilsel Thesis, a scientific proposal which traces the origins of western science to the interactions between scholars and skilled artisans. The proposal melded practical experimentation with analytical thought. As part of the left wing of the Vienna Circle (a group of early twentieth-century philosophers) he endorsed historical materialism, and sought to establish empirical laws in history and in society.
Zilsel was Jewish, and followed a Marxist political view. Both of which rendered him unable to pursue an academic career in Austria. Fleeing persecution, he escaped to the United States where he received a Rockefeller Fellowship Membership. During this time, he published many papers, such as the "Sociological Roots of Modern Science".
In 1943, he was invited to teach physics at Mills College in California, USA.
Edgar Zilsel passed away on March 11, 1944, from suicide.
Life
Edgar Zilsel was the youngest child of Jacob Zilsel, a lawyer, and Ina Kollmer. He had two older sisters, Wallie Zilsel and Irma Zilsel. He attended high school at the Franz-Joseph-Gymnasium between 1902 and 1910 and afterwards attended the University of Vienna where he studied philosophy, physics, and mathematics. In 1914, he also served in the military for four months and in 1915, he received his PhD while under the supervision of Heinrich Gomperz. His dissertation was entitled "A Philosophical Investigation of the Law of Large Numbers and Related Laws". After working as a mathematician at an insurance company for a few months, he found a position as a teacher on February 16, 1917. He passed his teacher's examination on November 18, 1918 in mathematics, physics, and natural history.
Although linked to the Vienna Circle, Zilsel critiqued the views of Circle members. He participated actively in working pe
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https://en.wikipedia.org/wiki/Artificial%20induction%20of%20immunity
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Artificial induction of immunity is immunization achieved by human efforts in preventive healthcare, as opposed to (and augmenting) natural immunity as produced by organisms' immune systems. It makes people immune to specific diseases by means other than waiting for them to catch the disease. The purpose is to reduce the risk of death and suffering, that is, the disease burden, even when eradication of the disease is not possible. Vaccination is the chief type of such immunization, greatly reducing the burden of vaccine-preventable diseases.
Immunity against infections that can cause serious illness is beneficial. Founded on a germ theory of infectious diseases, as demonstrated by Louis Pasteur's discoveries, modern medicine has provided means for inducing immunity against a widening range of diseases to prevent the associated risks from the wild infections. It is hoped that further understanding of the molecular basis of immunity will translate to improved clinical practice in the future.
Variolation and smallpox
The earliest recorded artificial induction of immunity in humans was by variolation or inoculation, which is the controlled infection of a subject with a less lethal natural form of smallpox (known as Variola Minor) to make him or her immune to re-infection with the more lethal natural form, Variola Major. This was practiced in ancient times in China and India, and imported into Europe, via Turkey, around 1720 by Lady Montagu and perhaps others. From England, the technique spread rapidly to the Colonies, and was also spread by African slaves arriving into Boston.
Variolation had the disadvantage that the inoculating agent used was still an active form of smallpox and, although less potent, could still kill the inoculee or spread in its full form to others nearby. However, as the risk of death from inoculation with Variola Minor was just 1% to 2%, as compared to the 20% risk of death from the natural form of smallpox, the risks of inoculation were ge
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https://en.wikipedia.org/wiki/Singmaster%27s%20conjecture
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Singmaster's conjecture is a conjecture in combinatorial number theory, named after the British mathematician David Singmaster who proposed it in 1971. It says that there is a finite upper bound on the multiplicities of entries in Pascal's triangle (other than the number 1, which appears infinitely many times). It is clear that the only number that appears infinitely many times in Pascal's triangle is 1, because any other number x can appear only within the first x + 1 rows of the triangle.
Statement
Let N(a) be the number of times the number a > 1 appears in Pascal's triangle. In big O notation, the conjecture is:
Known bound
Singmaster (1971) showed that
Abbot, Erdős, and Hanson (1974) (see References) refined the estimate to:
The best currently known (unconditional) bound is
and is due to Kane (2007). Abbot, Erdős, and Hanson note that conditional on Cramér's conjecture on gaps between consecutive primes that
holds for every .
Singmaster (1975) showed that the Diophantine equation
has infinitely many solutions for the two variables n, k. It follows that there are infinitely many triangle entries of multiplicity at least 6: For any non-negative i, a number a with six appearances in Pascal's triangle is given by either of the above two expressions with
where Fj is the jth Fibonacci number (indexed according to the convention that F0 = 0 and F1 = 1). The above two expressions locate two of the appearances; two others appear symmetrically in the triangle with respect to those two; and the other two appearances are at and
Elementary examples
2 appears just once; all larger positive integers appear more than once;
3, 4, 5 each appear two times; infinitely many appear exactly twice;
all odd prime numbers appear two times;
6 appears three times, as do all central binomial coefficients except for 1 and 2; (it is in principle not excluded that such a coefficient would appear 5, 7 or more times, but no such example is known)
all numbers of the form f
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https://en.wikipedia.org/wiki/Optical%20pumping
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Optical pumping is a process in which light is used to raise (or "pump") electrons from a lower energy level in an atom or molecule to a higher one. It is commonly used in laser construction to pump the active laser medium so as to achieve population inversion. The technique was developed by the 1966 Nobel Prize winner Alfred Kastler in the early 1950s.
Optical pumping is also used to cyclically pump electrons bound within an atom or molecule to a well-defined quantum state. For the simplest case of coherent two-level optical pumping of an atomic species containing a single outer-shell electron, this means that the electron is coherently pumped to a single hyperfine sublevel (labeled ), which is defined by the polarization of the pump laser along with the quantum selection rules. Upon optical pumping, the atom is said to be oriented in a specific sublevel, however, due to the cyclic nature of optical pumping, the bound electron will actually be undergoing repeated excitation and decay between the upper and lower state sublevels. The frequency and polarization of the pump laser determine the sublevel in which the atom is oriented.
In practice, completely coherent optical pumping may not occur due to power-broadening of the linewidth of a transition and undesirable effects such as hyperfine structure trapping and radiation trapping. Therefore the orientation of the atom depends more generally on the frequency, intensity, polarization, and spectral bandwidth of the laser as well as the linewidth and transition probability of the absorbing transition.
An optical pumping experiment is commonly found in physics undergraduate laboratories, using rubidium gas isotopes and displaying the ability of radiofrequency (MHz) electromagnetic radiation to effectively pump and unpump these isotopes.
See also
Atomic coherence
Laser pumping
Optical cavity
Rabi cycle
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https://en.wikipedia.org/wiki/Sphere%20theorem%20%283-manifolds%29
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In mathematics, in the topology of 3-manifolds, the sphere theorem of gives conditions for elements of the second homotopy group of a 3-manifold to be represented by embedded spheres.
One example is the following:
Let be an orientable 3-manifold such that is not the trivial group. Then there exists a non-zero element of having a representative that is an embedding .
The proof of this version of the theorem can be based on transversality methods, see .
Another more general version (also called the projective plane theorem, and due to David B. A. Epstein) is:
Let be any 3-manifold and a -invariant subgroup of . If is a general position map such that and is any neighborhood of the singular set , then there is a map satisfying
,
,
is a covering map, and
is a 2-sided submanifold (2-sphere or projective plane) of .
quoted in .
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https://en.wikipedia.org/wiki/Bali%20cattle
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The Bali cattle (Bos domesticus), also known as Balinese cattle, domestic banteng or Bali banteng, are a domesticated species of bovine which originated from the banteng (Bos javanicus). Bali cattle are an important source of meat and are used for plowing. They are thought to have originated in Bali.
History and range
The Bali cattle are one of the few species of true cattle that did not descend from the extinct aurochs. Their domestication occurred around 3500 BC, originating from banteng.
Bali cattle have been introduced to East Timor, Java, Malaysia and Australia as livestock, and account for about one fourth of the total cattle population of Indonesia. In eastern islands, they account for up to four-fifths of the cattle. In the Northern Territory of Australia, they have escaped from captivity and roam in large herds damaging crops.
Characteristics
Bali cattle have a hump, a white rump patch, white stockings, and white extending under the belly. Females are reddish-yellow, and males are reddish brown, turning to a dark brown with maturity. Compared to banteng, Bali cattle are smaller, demonstrate less obvious sexual dimorphism, have smaller horns, and have less developed withers. Body weights of males average from 335 to 363 kilograms, while females average from 211 kilograms to 242 kilograms.
Bali cattle are noted for their remarkable ability to grow on low-quality fodder and their high fertility.
Husbandry
The temperament of the Bali cattle is timid and deer-like, making them suitable for plowing rice paddy fields, but their hooves are too soft to pull cargo on paved roads. Mechanization and urbanization are making the cattle redundant as draft animals, however.
Meat from young Bali cattle is noted for being exceptionally tender.
Problems with the livestock include small birth and weaning weights, high calf mortality rates, slow growth rates, and low milk production.
Breeding
Artificial insemination was first introduced to Bali cattle in southern Su
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https://en.wikipedia.org/wiki/Eagle%2C%20Globe%2C%20and%20Anchor
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The Eagle, Globe, and Anchor (commonly referred to as an EGA) is the official emblem and insignia of the United States Marine Corps. The current emblem traces its roots in the designs and ornaments of the early Continental Marines as well as the United Kingdom's Royal Marines. The present emblem, adopted in 1955, differs from the emblem of 1868 only by a change in the eagle. Before that time many devices, ornaments, ribbons, and distinguishing marks followed one another as official badges of the corps.
History
In 1776, the device consisted of a fouled anchor (tangled in its rope) of silver or pewter. Changes were made in 1798, 1821, and 1824. In 1834, it was prescribed that a brass eagle be worn on the cover, the eagle to measure from wingtip to wingtip. An eagle clutching a fouled anchor with thirteen six-pointed stars above was used on uniform buttons starting in 1804. This same insignia is used today on the buttons of Marine dress and service uniforms, with the six-pointed stars changed to five-pointed stars.
During the early years numerous distinguishing marks were prescribed, including "black cockades", "scarlet plumes", and "yellow bands and tassels". In 1859, the first version of the present color scheme for the officer's dress uniform insignia appeared on an elaborate device of solid white metal and yellow metal. The design included a United States shield, half wreath, a bugle, and the letter "M."
In 1868, the USMC's commandant, Brigadier General Jacob Zeilin, appointed a board "to decide and report upon the various devices of cap ornaments of the Marine Corps." On November 13, 1868, the board recommended the modern insignia. It was approved by the commandant four days later, and by the Secretary of the Navy on November 19, 1868.
Design and symbolism
The emblem recommended by the 1868 board consisted of a globe (showing the continents of the Western Hemisphere) intersected by a fouled anchor, and surmounted by a spread eagle. On the emblem itself, the
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https://en.wikipedia.org/wiki/Spin%20ice
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A spin ice is a magnetic substance that does not have a single minimal-energy state. It has magnetic moments (i.e. "spin") as elementary degrees of freedom which are subject to frustrated interactions. By their nature, these interactions prevent the moments from exhibiting a periodic pattern in their orientation down to a temperature much below the energy scale set by the said interactions. Spin ices show low-temperature properties, residual entropy in particular, closely related to those of common crystalline water ice. The most prominent compounds with such properties are dysprosium titanate (Dy2Ti2O7) and holmium titanate (Ho2Ti2O7). The orientation of the magnetic moments in spin ice resembles the positional organization of hydrogen atoms (more accurately, ionized hydrogen, or protons) in conventional water ice (see figure 1).
Experiments have found evidence for the existence of deconfined magnetic monopoles in these materials, with properties resembling those of the hypothetical magnetic monopoles postulated to exist in vacuum.
Technical description
In 1935, Linus Pauling noted that the hydrogen atoms in water ice would be expected to remain disordered even at absolute zero. That is, even upon cooling to zero temperature, water ice is expected to have residual entropy, i.e., intrinsic randomness. This is due to the fact that the hexagonal crystalline structure of common water ice contains oxygen atoms with four neighboring hydrogen atoms. In ice, for each oxygen atom, two of the neighboring hydrogen atoms are near (forming the traditional H2O molecule), and two are further away (being the hydrogen atoms of two neighboring water molecules). Pauling noted that the number of configurations conforming to this "two-near, two-far" ice rule grows exponentially with the system size, and, therefore, that the zero-temperature entropy of ice was expected to be extensive. Pauling's findings were confirmed by specific heat measurements, though pure crystals of water ice
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https://en.wikipedia.org/wiki/Large%20countable%20ordinal
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In the mathematical discipline of set theory, there are many ways of describing specific countable ordinals. The smallest ones can be usefully and non-circularly expressed in terms of their Cantor normal forms. Beyond that, many ordinals of relevance to proof theory still have computable ordinal notations (see ordinal analysis). However, it is not possible to decide effectively whether a given putative ordinal notation is a notation or not (for reasons somewhat analogous to the unsolvability of the halting problem); various more-concrete ways of defining ordinals that definitely have notations are available.
Since there are only countably many notations, all ordinals with notations are exhausted well below the first uncountable ordinal ω1; their supremum is called Church–Kleene ω1 or ω (not to be confused with the first uncountable ordinal, ω1), described below. Ordinal numbers below ω are the recursive ordinals (see below). Countable ordinals larger than this may still be defined, but do not have notations.
Due to the focus on countable ordinals, ordinal arithmetic is used throughout, except where otherwise noted. The ordinals described here are not as large as the ones described in large cardinals, but they are large among those that have constructive notations (descriptions). Larger and larger ordinals can be defined, but they become more and more difficult to describe.
Generalities on recursive ordinals
Ordinal notations
Recursive ordinals (or computable ordinals) are certain countable ordinals: loosely speaking those represented by a computable function. There are several equivalent definitions of this: the simplest is to say that a computable ordinal is the order-type of some recursive (i.e., computable) well-ordering of the natural numbers; so, essentially, an ordinal is recursive when we can present the set of smaller ordinals in such a way that a computer (Turing machine, say) can manipulate them (and, essentially, compare them).
A different defin
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https://en.wikipedia.org/wiki/Long%20Josephson%20junction
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In superconductivity, a long Josephson junction (LJJ) is a Josephson junction which has one or more dimensions longer than the Josephson penetration depth . This definition is not strict.
In terms of underlying model a short Josephson junction is characterized by the Josephson phase , which is only a function of time, but not of coordinates i.e. the Josephson junction is assumed to be point-like in space. In contrast, in a long Josephson junction the Josephson phase can be a function of one or two spatial coordinates, i.e., or .
Simple model: the sine-Gordon equation
The simplest and the most frequently used model which describes the dynamics of the Josephson phase in LJJ is the so-called perturbed sine-Gordon equation. For the case of 1D LJJ it looks like:
where subscripts and denote partial derivatives with respect to and , is the Josephson penetration depth, is the Josephson plasma frequency, is the so-called characteristic frequency and is the bias current density normalized to the critical current density . In the above equation, the r.h.s. is considered as perturbation.
Usually for theoretical studies one uses normalized sine-Gordon equation:
where spatial coordinate is normalized to the Josephson penetration depth and time is normalized to the inverse plasma frequency . The parameter is the dimensionless damping parameter ( is McCumber-Stewart parameter), and, finally, is a normalized bias current.
Important solutions
Small amplitude plasma waves.
Soliton (aka fluxon, Josephson vortex):
Here , and are the normalized coordinate, normalized time and normalized velocity. The physical velocity is normalized to the so-called Swihart velocity , which represent a typical unit of velocity and equal to the unit of space divided by unit of time .
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https://en.wikipedia.org/wiki/Texture%20mapping%20unit
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In computer graphics, a texture mapping unit (TMU) is a component in modern graphics processing units (GPUs). They are able to rotate, resize, and distort a bitmap image to be placed onto an arbitrary plane of a given 3D model as a texture, in a process called texture mapping. In modern graphics cards it is implemented as a discrete stage in a graphics pipeline, whereas when first introduced it was implemented as a separate processor, e.g. as seen on the Voodoo2 graphics card.
Background and history
The TMU came about due to the compute demands of sampling and transforming a flat image (as the texture map) to the correct angle and perspective it would need to be in 3D space. The compute operation is a large matrix multiply, which CPUs of the time (early Pentiums) could not cope with at acceptable performance.
In 2013, TMUs are part of the shader pipeline and decoupled from the Render Output Pipelines (ROPs). For example, in AMD's Cypress GPU, each shader pipeline (of which there are 20) has four TMUs, giving the GPU 80 TMUs. This is done by chip designers to closely couple shaders and the texture engines they will be working with.
Geometry
3D scenes are generally composed of two things: 3D geometry, and the textures that cover that geometry. Texture units in a video card take a texture and 'map' it to a piece of geometry. That is, they wrap the texture around the geometry and produce textured pixels which can then be written to the screen.
Textures can be an actual image, a lightmap, or even normal maps for advanced surface lighting effects.
Texture fill rate
To render a 3D scene, textures are mapped over the top of polygon meshes. This is called texture mapping and is accomplished by texture mapping units (TMUs) on the videocard. Texture fill rate is a measure of the speed with which a particular card can perform texture mapping.
Though pixel shader processing is becoming more important, this number still holds some weight. Best example of this is the X1600
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https://en.wikipedia.org/wiki/Current%20limiting
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Current limiting is the practice of imposing a limit on the current that may be delivered to a load to protect the circuit generating or transmitting the current from harmful effects due to a short-circuit or overload. The term "current limiting" is also used to define a type of overcurrent protective device. According to the 2020 NEC/NFPA 70, a current-limiting overcurrent protective device is defined as, "A device that, when interrupting currents in its current-limiting range, reduces the current flowing in the faulted circuit to a magnitude substantially less than that obtainable in the same circuit if the device were replaced with a solid conductor having compatible impedance."
Inrush current limiting
An inrush current limiter is a device or devices combination used to limit inrush current. Passive resistive components such as resistors (with power dissipation drawback), or negative temperature coefficient (NTC) thermistors are simple options while the positive one (PTC) is used to limit max current afterward as the circuit has been operating (with cool-down time drawback on both). More complex solutions using active components can be used when more straightforward options are unsuitable.
In electronic power circuits
Some electronic circuits employ active current limiting since a fuse may not protect solid-state devices.
One style of current limiting circuit is shown in the image. The schematic represents a simple protection mechanism used in regulated DC supplies and class-AB power amplifiers.
Q1 is the pass or output transistor. Rsens is the load current sensing device. Q2 is the protection transistor which turns on as soon as the voltage across Rsens becomes about 0.65 V. This voltage is determined by the value of Rsens and the load current through it (Iload). When Q2 turns on, it removes the base current from Q1, thereby reducing the collector current of Q1, which is nearly the load current. Thus, Rsens fixes the maximum current to a value given by 0.6
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https://en.wikipedia.org/wiki/Abietoideae
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Abietoideae is a subfamily of the conifer family Pinaceae. The name is from the genus Abies (firs), which contains most of the species in the genus. Six genera are currently assigned to this subfamily: Abies, Cedrus, Keteleeria, Nothotsuga, Pseudolarix, and Tsuga.
The group was formerly treated as a separate family, the Abietaceae, by some plant taxonomy systems, such as the Wettstein system.
Genera and species
Abies - firs
Abies alba— silver fir
Abies amabilis—Pacific silver fir
Abies balsamea—balsam fir
Abies beshanzuensis—Baishanzu fir
Abies borisii-regis— Bulgarian fir
Abies bracteata—bristlecone fir
Abies cephalonica— Greek fir
Abies chensiensis—Shensi fir
Abies cilicica—Syrian fir
Abies concolor—white fir
Abies delavayi—Delavay's fir
Abies densa—Bhutan fir
Abies durangensis—Durango fir
Abies fabri—Faber's fir
Abies fanjingshanensis—Fanjingshan fir
Abies fargesii— Farges' fir
Abies firma—Momi fir
Abies flinckii—Jalisco fir
Abies forrestii—Forrest's fir
Abies fraseri—Fraser fir
Abies grandis— grand fir or giant fir
Abies guatemalensis—Guatemalan fir
Abies hickelii—Hickel's fir
Abies holophylla—Manchurian fir
Abies homolepis—Nikko fir
Abies kawakamii—Taiwan fir
Abies koreana—Korean fir
Abies lasiocarpa—subalpine fir
Abies magnifica—red fir
Abies mariesii—Maries' fir
Abies milleri—Early Eocene
Abies nebrodensis— Sicilian fir
Abies nephrolepis—Khinghan fir
Abies nordmanniana— Nordmann fir or Caucasian fir
Abies numidica—Algerian fir
Abies pindrow—Pindrow fir
Abies pinsapo—Spanish fir
Abies procera—noble fir
Abies recurvata—Min fir
Abies religiosa—sacred fir
Abies sachalinensis—Sakhalin fir
Abies sibirica—Siberian fir
Abies spectabilis—East Himalayan fir
Abies squamata—flaky fir
Abies veitchii—Veitch's fir
Abies vejarii
Abies yuanbaoshanensis—Yuanbaoshan fir
Abies ziyuanensis—Ziyuan fir
Cedrus
Cedrus atlantica
Cedrus brevifolia
Cedrus deodara
Cedrus libani
Keteleeria
Keteleeria davidiana
Keteleeria evelynian
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https://en.wikipedia.org/wiki/SSHFS
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In computing, SSHFS (SSH Filesystem) is a filesystem client to mount and interact with directories and files located on a remote server or workstation over a normal ssh connection. The client interacts with the remote file system via the SSH File Transfer Protocol (SFTP), a network protocol providing file access, file transfer, and file management functionality over any reliable data stream that was designed as an extension of the Secure Shell protocol (SSH) version 2.0.
The current implementation of SSHFS using FUSE is a rewrite of an earlier version. The rewrite was done by Miklos Szeredi, who also wrote FUSE.
Features
SFTP provides secure file transfer from a remote file system. While SFTP clients can transfer files and directories, they cannot mount the server's file system into the local directory tree. Using SSHFS, a remote file system may be treated in the same way as other volumes (such as hard drives or removable media).
Using the Unix command ls with sshfs will sometimes not list the owner of a file correctly, although it is possible to map them manually.
For distributed remote file systems with multiple users, protocols such as Apple Filing Protocol, Network File System and Server Message Block are more often used. SSHFS is an alternative to those protocols only in situations where users are confident that files and directories will not be targeted for writing by another user, at the same time.
The advantage of SSHFS when compared to other network file system protocols is that, given that a user already has SSH access to a host, it does not require any additional configuration work, or the opening of additional entry ports in a firewall.
See also
ExpanDrive
Files transferred over shell protocol (FISH)
FileZilla, a free software utility for multiple platforms.
FTPFS
GVfs
SSH file transfer protocol (SFTP)
Secure copy (SCP)
WinSCP
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https://en.wikipedia.org/wiki/Secondary%20fermentation%20%28wine%29
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Secondary fermentation is a process commonly associated with winemaking, which entails a second period of fermentation in a different vessel than the one used to start the fermentation process. An example of this would be starting fermentation in a carboy or stainless steel tank and then moving it over to oak barrels. Rather than being a separate, second fermentation, this is most often one single fermentation period that is conducted in multiple vessels. However, the term does also apply to procedures that could be described as a second and distinct fermentation period.
In wine production
In sparkling wine production, the secondary fermentation often takes places in the wine bottle that the wine will be sold in. This is most commonly known as the méthode champenoise or "Champagne method" after the region most noted for sparkling wine production. When the base wine (or cuvee) has been produced from single grape varietals or a blend, the wine is bottled with a mixture of yeast and fresh sugar known as the "liqueur de tirage". This secondary fermentation, also known as bottle fermentation, is the process that makes the wine "bubbly" due to the containment of carbon dioxide which is normally released as a by product in regular fermentation.
In still wine production, particularly of red wines and some white wines like Chardonnay, the secondary fermentation process can also usher in the use of malolactic fermentation (or MLF) where the hard, green apple-like malic acid is converted into softer, butter-like lactic acid. In the case of a stuck fermentation, a winemaker may wish to transfer the must to a second vessel and use stronger, more aggressive yeasts with high fermentation temperatures to re-initiate the fermentation process. A similar process known as governo has been used by Tuscan winemakers since the 14th century with the isolation after harvest of a batch of grapes that can be added later to the wine to help prevent (or recover from) a stuck fermentation.
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https://en.wikipedia.org/wiki/FpgaC
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FpgaC is a compiler for a subset of the C programming language, which produces digital circuits that will execute the compiled programs. The circuits may use FPGAs or CPLDs as the target processor for reconfigurable computing, or even ASICs for dedicated applications. FpgaC's goal is to be an efficient High Level Language (HLL) for reconfigurable computing, rather than a Hardware Description Language (HDL) for building efficient custom hardware circuits.
History
The historical roots of FpgaC are in the Transmogrifier C 3.1 (TMCC) HDL, a 1996 BSD licensed Open source offering from University of Toronto. TMCC is one of the first FPGA C compilers, with work starting in 1994 and presented at IEEE's FCCM95. This predated the evolution from the Handel language to Handel-C work done shortly afterward at Oxford University Computing Laboratory.
TMCC was renamed FpgaC for the initial SourceForge project release, with syntax modifications to start the evolution to ANSI C. Later development has removed all explicit HDL syntax from the language, and increased the subset of C supported. By capitalizing on ANSI C C99 extensions, the same functionality is now available by inference rather than non-standard language extensions. This shift away from non-standard HDL extensions was influenced in part by Streams-C from Los Alamos National Laboratory (now available commercially as Impulse C).
In the years that have followed, compiling ANSI C for execution as FPGA circuits has become a mainstream technology. Commercial FPGA C compilers are available from multiple vendors, and ANSI C based System Level Tools have gone mainstream for system description and simulation languages. FPGA based Reconfigurable Computing offerings from industry leaders like Altera, Silicon Graphics, Seymour Cray's SRC Computers, and Xilinx have capitalized on two decades of government and university reconfigurable computing research.
External links
Transmogrifier C Homepage
Oxford Handel-C
FPGA System Le
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https://en.wikipedia.org/wiki/London%20penetration%20depth
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In superconductors, the London penetration depth (usually denoted as or ) characterizes the distance to which a magnetic field penetrates into a superconductor and becomes equal to times that of the magnetic field at the surface of the superconductor. Typical values of λL range from 50 to 500 nm.
The London penetration depth results from considering the London equation and Ampère's circuital law. If one considers a superconducting half-space, i.e superconducting for x>0, and weak external magnetic field B0 applied along z direction in the empty space x<0, then inside the superconductor the magnetic field is given by
can be seen as the distance across in which the magnetic field becomes times weaker. The form of is found by this method to be
for charge carriers of mass , number density and charge .
The penetration depth is determined by the superfluid density, which is an important quantity that determines Tc in high-temperature superconductors. If some superconductors have some node in their energy gap, the penetration depth at 0 K depends on magnetic field because superfluid density is changed by magnetic field and vice versa. So, accurate and precise measurements of the absolute value of penetration depth at 0 K are very important to understand the mechanism of high-temperature superconductivity.
There are various experimental techniques to determine the London penetration depth, and in particular its temperature dependence. London penetration depth can be measured by muon spin spectroscopy when the superconductor does not have an intrinsic magnetic constitution. The penetration depth is directly converted from the depolarization rate of muon spin in relation which
σ(T) is proportional to λ2(T). The shape of σ(T) is different with the kind of superconducting energy gap in temperature, so that this immediately indicates the shape of energy gap and gives some clues about the origin of superconductivity to us.
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https://en.wikipedia.org/wiki/Commitment%20ordering
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Commitment ordering (CO) is a class of interoperable serializability techniques in concurrency control of databases, transaction processing, and related applications. It allows optimistic (non-blocking) implementations. With the proliferation of multi-core processors, CO has also been increasingly utilized in concurrent programming, transactional memory, and software transactional memory (STM) to achieve serializability optimistically. CO is also the name of the resulting transaction schedule (history) property, defined in 1988 with the name dynamic atomicity. In a CO compliant schedule, the chronological order of commitment events of transactions is compatible with the precedence order of the respective transactions. CO is a broad special case of conflict serializability and effective means (reliable, high-performance, distributed, and scalable) to achieve global serializability (modular serializability) across any collection of database systems that possibly use different concurrency control mechanisms (CO also makes each system serializability compliant, if not already).
Each not-CO-compliant database system is augmented with a CO component (the commitment order coordinator—COCO) which orders the commitment events for CO compliance, with neither data-access nor any other transaction operation interference. As such, CO provides a low overhead, general solution for global serializability (and distributed serializability), instrumental for global concurrency control (and distributed concurrency control) of multi-database systems and other transactional objects, possibly highly distributed (e.g., within cloud computing, grid computing, and networks of smartphones). An atomic commitment protocol (ACP; of any type) is a fundamental part of the solution, utilized to break global cycles in the conflict (precedence, serializability) graph. CO is the most general property (a necessary condition) that guarantees global serializability, if the database systems involved do n
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https://en.wikipedia.org/wiki/Condyloid%20process
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The condyloid process or condylar process is the process on the human and other mammalian species' mandibles that ends in a condyle, the mandibular condyle. It is thicker than the coronoid process of the mandible and consists of two portions: the condyle and the constricted portion which supports it, the neck.
Condyle
The most superior part of the mandible, the condyle presents an articular surface for articulation with the articular disk of the temporomandibular joint; it is convex from before backward and from side to side, and extends farther on the posterior than on the anterior surface.
Its long axis is directed medialward and slightly backward, and if prolonged to the middle line will meet that of the opposite condyle near the anterior margin of the foramen magnum.
At the lateral extremity of the condyle is a small tubercle for the attachment of the temporomandibular ligament.
The articular surface of the condyle is covered by fibrous tissue, and interfaces with an articular disk (or meniscus) of avascular, non-innervated fibrous tissue (collagen, fibroblasts). When the mouth is closed the meniscus is bordered medially and superiorly by the glenoid fossa of the petrous portion of the temporal bone. When the mouth is opened maximally, the meniscus is distracted anteriorly and inferiorly along the slope of the inferior portion of the temporal bone towards the tubercle, or articular eminence, in order to remain interposed between the condyle and the temporal bone in all jaw positions.
Neck
The neck of the process rises from the posterior of the ramus mandibulae. It is flattened from before backward, and strengthened by ridges which descend from the forepart and sides of the condyle.
Its posterior surface is convex; its anterior surface has a depression for the attachment of the lateral pterygoid muscle.
Fractures
Because the articular disk prevents the mandible from moving posteriorly, the condylar neck is often subject to fracturing when the jaw suffer
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https://en.wikipedia.org/wiki/Naming%20collision
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A naming collision is a circumstance where two or more identifiers in a given namespace or a given scope cannot be unambiguously resolved, and such unambiguous resolution is a requirement of the underlying system.
Example: XML element names
In XML, element names can be originated and changed to reflect the type of information contained in the document. This level of flexibility may cause problems if separate documents encode different kinds of information, but use the same identifiers for the element names.
For example, the following sample document defines the basic semantics for a "person" document and a "book" document. Both of these use a "title" element, but the meaning is not the same:
<root>
<person>
<fname>Nancy</fname>
<lname>Davolio</lname>
<title>Dr.</title>
<age>29</age>
</person>
<book>
<title>Harry Potter And The Cursed Child</title>
<isbn>ABCD1234567</isbn>
</book>
</root>
For an application to allow a user to correctly query for and retrieve the "title" element, it must provide a way to unambiguously specify which title element is being requested. Failure to do so would give rise to a naming collision on the title element (as well as any other elements that shared this unintended similarity).
In the preceding example, there is enough information in the structure of the document itself (which is specified by the "root" element) to provide a means of unambiguously resolving element names.
For example, using XPath:
//root/person/title ;; the formal title for a person
//root/book/title ;; the title of a book
Collision domain
The term collision domain may also be used to refer to a system in which a single name or identifier is open to multiple interpretations by different layers or processing. The notion of a namespace has been widely adopted as a software programming practice to avert undesired clashes. Note that its use in the networking field is
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https://en.wikipedia.org/wiki/BSSGP
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BSSGP is a protocol used in the GPRS mobile packet data system. It denotes Base Station System GPRS Protocol. It transfers information between two GPRS entities SGSN and BSS over a BSSGP Virtual Connection (BVC). This protocol provides radio-related quality of service and routing information that is required to transmit user data between a BSS and an SGSN. It does not carry out any form of error correction.
BSSGP is used to handle the flow control between SGSN and BSS. The flow control mechanism implemented in SGSN node, only for GSM, is used to prevent congestion and loss of data due to overload in the BSS. This mechanism controls the flow from the SGSN to the BSS but not in the uplink direction.
The primary functions of BSSGP include:
Provision by an SGSN to a BSS of a radio related information used by the RLC/MAC function in the download link.
Provision by a BSS to an SGSN of radio related information derived from the RLC/MAC function in the uplink.
Provision of functionality to enable two physically distinct nodes, an SGSN, a BSS, to operate node management control functions (QoS, flow control).
It is specified in 3GPP TS 48.018.
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https://en.wikipedia.org/wiki/Sphenoidal%20conchae
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The sphenoidal conchae (sphenoidal turbinated processes) are two thin, curved plates, situated at the anterior and lower part of the body of the sphenoid. An aperture of variable size exists in the anterior wall of each, and through this the sphenoidal sinus opens into the nasal cavity.
Each is irregular in form, and tapers to a point behind, being broader and thinner in front.
Its upper surface is concave, and looks toward the cavity of the sinus; its under surface is convex, and forms part of the roof of the corresponding nasal cavity.
Each bone articulates in front with the ethmoid, laterally with the palatine; its pointed posterior extremity is placed above the vomer, and is received between the root of the pterygoid process laterally and the rostrum of the sphenoid medially.
A small portion of the sphenoidal concha sometimes enters into the formation of the medial wall of the orbit, between the lamina papyracea of the ethmoid in front, the orbital plate of the palatine below, and the frontal bone above.
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https://en.wikipedia.org/wiki/Pterygoid%20processes%20of%20the%20sphenoid
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The pterygoid processes of the sphenoid (from Greek pteryx, pterygos, "wing"), one on either side, descend perpendicularly from the regions where the body and the greater wings of the sphenoid bone unite.
Each process consists of a medial pterygoid plate and a lateral pterygoid plate, the latter of which serve as the origins of the medial and lateral pterygoid muscles. The medial pterygoid, along with the masseter allows the jaw to move in a vertical direction as it contracts and relaxes. The lateral pterygoid allows the jaw to move in a horizontal direction during mastication (chewing). Fracture of either plate are used in clinical medicine to distinguish the Le Fort fracture classification for high impact injuries to the sphenoid and maxillary bones.
The superior portion of the pterygoid processes are fused anteriorly; a vertical groove, the pterygopalatine fossa, descends on the front of the line of fusion. The plates are separated below by an angular cleft, the pterygoid notch, the margins of which are rough for articulation with the pyramidal process of the palatine bone.
The two plates diverge behind and enclose between them a V-shaped fossa, the pterygoid fossa, which contains the medial pterygoid muscle and the tensor veli palatini.
Above this fossa is a small, oval, shallow depression, the scaphoid fossa, which gives origin to the tensor veli palatini.
The anterior surface of the pterygoid process is broad and triangular near its root, where it forms the posterior wall of the pterygopalatine fossa and presents the anterior orifice of the pterygoid canal.
In many mammals it remains as a separate bone called the pterygoid bone.
Its name is Greek for "resembling a fin or wing", from its shape.
Medial pterygoid plate
The medial pterygoid plate (or medial pterygoid lamina) of the sphenoid bone is a horse-shoe shaped process that arises from its underside.
It is narrower and longer than the lateral pterygoid plate and curves lateralward at its lower ext
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https://en.wikipedia.org/wiki/Greater%20wing%20of%20sphenoid%20bone
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The greater wing of the sphenoid bone, or alisphenoid, is a bony process of the sphenoid bone; there is one on each side, extending from the side of the body of the sphenoid and curving upward, laterally, and backward.
Structure
The greater wings of the sphenoid are two strong processes of bone, which arise from the sides of the body, and are curved upward, laterally, and backward; the posterior part of each projects as a triangular process that fits into the angle between the squamous and the petrous part of the temporal bone and presents at its apex a downward-directed process, the spine of sphenoid bone.
Cerebral surface
The superior or cerebral surface of each greater wing [Fig. 1] forms part of the middle cranial fossa; it is deeply concave, and presents depressions for the convolutions of the temporal lobe of the brain. It has a number of foramina (holes) in it:
The foramen rotundum is a circular aperture at its anterior and medial part; it transmits the maxillary nerve.
The foramen ovale is behind and lateral to this; it transmits the mandibular nerve, the accessory meningeal artery, and sometimes the lesser petrosal nerve.
The sphenoidal emissary foramen is occasionally present; it is a small aperture medial to the foramen ovale, opposite the root of the pterygoid process; it opens below near the scaphoid fossa, and transmits a small vein from the cavernous sinus.
The foramen spinosum, in the posterior angle near to and in front of the spine; it is a short canal that transmits the middle meningeal vessels and a recurrent branch from the mandibular nerve.
The foramen petrosum, a small occasional opening, between the foramen spinosum and foramen ovale, for transmission of the lesser petrosal nerve.
Lateral surface
The lateral surface [Fig. 2] is convex, and divided by a transverse ridge, the infratemporal crest, into two portions.
The superior temporal surface, convex from above downward, concave from before backward, forms a part of the tempor
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https://en.wikipedia.org/wiki/Lesser%20wing%20of%20sphenoid%20bone
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The lesser wings of the sphenoid or orbito-sphenoids are two thin triangular plates, which arise from the upper and anterior parts of the body, and, projecting lateralward, end in sharp points [Fig. 1].
In some animals they remain as separate bones called orbitosphenoids.
Structure
The main features of the lesser wing are the optic canal, the anterior clinoid process, and the superior orbital fissure.
Surfaces
The superior surface of each is flat, and supports part of the frontal lobe of the brain. The inferior surface forms the back part of the roof of the orbit, and the upper boundary of the superior orbital fissure.
This fissure is of a triangular form, and leads from the cavity of the cranium into that of the orbit: it is bounded medially by the body; above, by the small wing; below, by the medial margin of the orbital surface of the great wing; and is completed laterally by the frontal bone.
It transmits the oculomotor nerve, the trochlear nerve, and the abducent nerve, the three branches of the ophthalmic division of the trigeminal nerve, some filaments from the cavernous plexus of the sympathetic nervous system, the orbital branch of the middle meningeal artery, a recurrent branch from the lacrimal artery to the dura mater, and the ophthalmic vein.
Borders
The anterior border is serrated for articulation with the frontal bone.
The posterior border, smooth and rounded, is received into the lateral fissure of the brain; the medial end of this border forms the anterior clinoid process, which gives attachment to the tentorium cerebelli; it is sometimes joined to the middle clinoid process by a spicule of bone, and when this occurs the termination of the groove for the internal carotid artery is converted into a foramen (carotico-clinoid).
The lesser wing is connected to the body by two roots, the upper thin and flat, the lower thick and triangular; between the two roots is the optic foramen, for the transmission of the optic nerve and ophthalmic artery.
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https://en.wikipedia.org/wiki/Ethmoidal%20labyrinth
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The ethmoidal labyrinth or lateral mass of the ethmoid bone consists of a number of thin-walled cellular cavities, the ethmoid air cells, arranged in three groups, anterior, middle, and posterior, and interposed between two vertical plates of bone; the lateral plate forms part of the orbit, the medial plate forms part of the nasal cavity. In the disarticulated bone many of these cells are opened into, but when the bones are articulated, they are closed in at every part, except where they open into the nasal cavity.
Surfaces
The upper surface of the labyrinth presents a number of half-broken cells, the walls of which are completed, in the articulated skull, by the edges of the ethmoidal notch of the frontal bone. Crossing this surface are two grooves, converted into two openings by articulation with the frontal; they are the anterior and posterior ethmoidal foramina, and open on the inner wall of the orbit. The posterior surface presents large irregular cellular cavities, which are closed in by articulation with the sphenoidal concha and orbital process of palatine bone. The lateral surface is formed of a thin, smooth, oblong plate, the lamina papyracea (os planum), which covers in the middle and posterior ethmoidal cells and forms a large part of the medial wall of the orbit; it articulates above with the orbital plate of the frontal bone, below with the maxilla and orbital process of the palatine, in front with the lacrimal, and behind with the sphenoid.
In front of the lamina papyracea are some broken air cells which are overlapped and completed by the lacrimal bone and the frontal process of the maxilla. A curved lamina, the uncinate process, projects downward and backward from this part of the labyrinth; it forms a small part of the medial wall of the maxillary sinus, and articulates with the ethmoidal process of the inferior nasal concha.
The medial surface of the labyrinth forms part of the lateral wall of the corresponding nasal cavity. It consists of a t
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https://en.wikipedia.org/wiki/Perpendicular%20plate%20of%20ethmoid%20bone
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The perpendicular plate of the ethmoid bone (vertical plate) is a thin, flattened lamina, polygonal in form, which descends from the under surface of the cribriform plate, and assists in forming the septum of the nose; it is generally deflected a little to one or other side. The anterior border articulates with the spine of the frontal bone and the crest of the nasal bones.
The posterior border articulates by its upper half with the sphenoidal crest, by its lower with the vomer.
The inferior border is thicker than the posterior, and serves for the attachment of the septal nasal cartilage of the nose.
The surfaces of the plate are smooth, except above, where numerous grooves and canals are seen; these lead from the medial foramina on the cribriform plate and lodge filaments of the olfactory nerves.
Additional images
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https://en.wikipedia.org/wiki/Nuclear%20explosion
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A nuclear explosion is an explosion that occurs as a result of the rapid release of energy from a high-speed nuclear reaction. The driving reaction may be nuclear fission or nuclear fusion or a multi-stage cascading combination of the two, though to date all fusion-based weapons have used a fission device to initiate fusion, and a pure fusion weapon remains a hypothetical device. Nuclear explosions are used in nuclear weapons and nuclear testing.
Atmospheric nuclear explosions are associated with mushroom clouds, although mushroom clouds can occur with large chemical explosions. It is possible to have an air-burst nuclear explosion without those clouds. Nuclear explosions produce radiation and radioactive debris that is harmful to humans and can cause moderate to severe skin burns, eye damage, radiation sickness, radiation-induced cancer and possible death depending on how far a person is from the blast radius. Nuclear explosions can also have detrimental effects on the climate, lasting from months to years. In a 1983 article, Carl Sagan claimed that a small-scale nuclear war could release enough particles into the atmosphere to cause the planet to cool and cause crops, animals, and agriculture to disappear across the globe—an effect named nuclear winter.
History
The beginning (fission explosions)
The first manmade nuclear explosion occurred on July 16, 1945, at 5:50 am on the Trinity test site near Alamogordo, New Mexico, in the United States, an area now known as the White Sands Missile Range. The event involved the full-scale testing of an implosion-type fission atomic bomb. In a memorandum to the U.S. Secretary of War, General Leslie Groves describes the yield as equivalent to 15,000 to 20,000 tons of TNT. Following this test, a uranium-gun type nuclear bomb (Little Boy) was dropped on the Japanese city of Hiroshima on August 6, 1945, with a blast yield of 15 kilotons; and a plutonium implosion-type bomb (Fat Man) on Nagasaki on August 9, 1945, with a blast
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https://en.wikipedia.org/wiki/Leucanthemum%20%C3%97%20superbum
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Leucanthemum × superbum, the Shasta daisy, is a commonly grown flowering herbaceous perennial plant with the classic daisy appearance of white petals (ray florets) around a yellow disc, similar to the oxeye daisy Leucanthemum vulgare Lam, but larger.
It originated as a hybrid produced in 1890 by the American horticulturist Luther Burbank from a number of daisies. First, he crossed Leucanthemum vulgare with Leucanthemum maximum; this double hybrid was itself crossed with Leucanthemum lacustre. The resulting Leucanthemum triple hybrid was crossed with Nipponanthemum nipponicum, creating an intergeneric cross of species from three continents. It was named after Mount Shasta, because its petals were the color of the snow. Some members of the genus are considered noxious weeds, but the Shasta daisy remains a favorite garden plant.
Many cultivars are suitable for cut flowers, such as 'Becky', 'Esther Read', 'Silberprinzesschen' (), 'Snow Lady', 'Tinkerbell', 'Wirral Pride', 'Wirral Supreme'. The cultivars 'T.E. Killin' and 'Wirral Supreme' have gained the Royal Horticultural Society's Award of Garden Merit.
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https://en.wikipedia.org/wiki/Inferior%20orbital%20fissure
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The inferior orbital fissure is a gap between the greater wing of sphenoid bone, and the maxilla. It connects the orbit (anteriorly) with the infratemporal fossa and pterygopalatine fossa (posteriorly).
Anatomy
The medial end of the inferior orbital fissure diverges laterally from the medial end of the superior orbital fissure. It is situated between the lateral wall of the orbit and the floor of the orbit.
Contents
The fissure gives passage to multiple structures, including:
Infraorbital nerve, artery and vein
Inferior ophthalmic vein
Zygomatic nerve
Orbital branches of the pharyngeal nerve
Additional images
See also
Foramina of skull
Superior orbital fissure
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https://en.wikipedia.org/wiki/Remote%20Initial%20Program%20Load
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Remote Initial Program Load (RIPL or RPL) is a protocol for starting a computer and loading its operating system from a server via a network. Such a server runs a network operating system such as LAN Manager, LAN Server, Windows NT Server, Novell NetWare, LANtastic, Solaris or Linux.
RIPL is similar to Preboot Execution Environment (PXE), but it uses the Novell NetWare-based boot method. It was originally developed by IBM.
IBM LAN Server
IBM LAN Server enables clients (RIPL requesters) to load the operating systems DOS or OS/2 via the 802.2/DLC-protocol from the LAN (often Token Ring). Therefore, the server compares the clients' requests with entries in its RPL.MAP table. Remote booting DOS workstations via boot images was supported as early as 1990 by IBM LAN Server 1.2 via its PCDOSRPL protocol. IBM LAN Server 2.0 introduced remote booting of OS/2 stations (since OS/2 1.30.1) in 1992.
RPL and DOS
For DOS remote boot to work, the RPL boot loader is loaded into the client's memory over the network before the operating system starts. Without special precautions the operating system could easily overwrite the RPL code during boot, since the RPL code resides in unallocated memory (typically at the top of the available conventional memory). The RPL code hides and thereby protects itself from being overwritten by hooking INT 12h and reducing the memory reported by this BIOS service by its own size. INT 12h is used by DOS to query the amount of available memory when initializing its own real-mode memory allocation scheme. This causes problems on more modern DOS systems, where free real-mode address ranges may be utilized by the operating system in order to relocate parts of itself and load drivers high, so that the amount of available conventional memory is maximized. Typically, various operating system vendor and version specific "dirty tricks" had to be used by the RPL code in order to survive this very dynamic boot process and let DOS regain control over the memor
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https://en.wikipedia.org/wiki/Semantic%20integration
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Semantic integration is the process of interrelating information from diverse sources, for example calendars and to do lists, email archives, presence information (physical, psychological, and social), documents of all sorts, contacts (including social graphs), search results, and advertising and marketing relevance derived from them. In this regard, semantics focuses on the organization of and action upon information by acting as an intermediary between heterogeneous data sources, which may conflict not only by structure but also context or value.
Applications and methods
In enterprise application integration (EAI), semantic integration can facilitate or even automate the communication between computer systems using metadata publishing. Metadata publishing potentially offers the ability to automatically link ontologies. One approach to (semi-)automated ontology mapping requires the definition of a semantic distance or its inverse, semantic similarity and appropriate rules. Other approaches include so-called lexical methods, as well as methodologies that rely on exploiting the structures of the ontologies. For explicitly stating similarity/equality, there exist special properties or relationships in most ontology languages. OWL, for example has "owl:equivalentClass", "owl:equivalentProperty" and "owl:sameAs".
Eventually system designs may see the advent of composable architectures where published semantic-based interfaces are joined together to enable new and meaningful capabilities. These could predominately be described by means of design-time declarative specifications, that could ultimately be rendered and executed at run-time.
Semantic integration can also be used to facilitate design-time activities of interface design and mapping. In this model, semantics are only explicitly applied to design and the run-time systems work at the syntax level. This "early semantic binding" approach can improve overall system performance while retaining the benefits of se
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https://en.wikipedia.org/wiki/Virtual%20COM%20port
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A virtual serial port is a software representation of a serial port that either does not connect to a real serial port, or adds functionality to a real serial port through software extension.
Software virtual ports
A software-based virtual serial port presents one or more virtual serial port identifiers on a PC which other applications can see and interact with as if they were real hardware ports, but the data sent and received to these virtual devices is handled by software that manipulates the transmitted and received data to grant greater functionality.
Operating systems usually do not provide virtual serial port capability. Third-party applications can add this ability, such as the open-source com0com, freeware HW VSP3, or the commercial Virtual Serial Port Driver.
Some virtual serial ports emulate all hardware serial port functionality, including all signal pin states, and permit a large number of virtual ports in any desired configuration. Others provide a limited set of capabilities and do not fully emulate the hardware.
This technique can be used either to extend the capabilities of software that cannot be updated to use newer communication technologies, such as by transmitting serial data over modern networks, or to achieve data flows that are not normally possible due to software limitations, such as splitting serial port output.
Port sharing
A serial port typically can only be monitored or transmitted to by one device at a time under the constraints of most operating systems, but a virtual serial port program can create two virtual ports, allowing two separate applications to monitor the same data. For instance, a GPS device which outputs location data to a PCs serial port may be of interest to multiple applications at once.
Network transmission
Another option is to communicate with another serial device via internet or LAN as if they were locally connected, using serial over LAN. This allows software intended to interface with a device over a lo
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https://en.wikipedia.org/wiki/Energy%20Sciences%20Network
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The Energy Sciences Network (ESnet) is a high-speed computer network serving United States Department of Energy (DOE) scientists and their collaborators worldwide. It is managed by staff at the Lawrence Berkeley National Laboratory.
More than 40 DOE Office of Science labs and research sites are directly connected to this network. The ESnet network also connects research and commercial networks, allowing DOE researchers to collaborate with scientists around the world.
Overview
The Energy Sciences Network (ESnet) is the Office of Science's network user facility, delivering data transport capabilities for the requirements of large-scale science. Formed in 1986, combining the operations of earlier DOE networking projects known as HEPnet (for high-energy physics) and MFEnet (for magnetic fusion energy research), ESnet is stewarded by the Scientific Computing Research Program, managed and operated by the Scientific Networking Division at Lawrence Berkeley National Laboratory and is used to enable the DOE science mission.
ESnet interconnects the DOE's national laboratory system, dozens of other DOE sites, research and commercial networks around the world, enabling scientists at DOE laboratories and academic institutions across the country to transfer data streams and access remote research resources in real time.
ESnet provides the networking infrastructure and services required by the national laboratories, large science collaborations, and the DOE research community. ESnet services aim to provide bandwidth connections to enable scientists to collaborate across a range of research areas across the USA and, since December 2014, Europe with a view to enhancing collaboration.
According to ESnet's own figures, during the period 1990 to 2019, average traffic volumes have grown by a factor of 10 every 47 months.
In 2009, ESnet received $62 million in American Research and Recovery Act (ARRA) funding from the DOE Office of Science to invest in its infrastructure to prov
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https://en.wikipedia.org/wiki/Supercurrent
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A supercurrent is a superconducting current, that is, electric current which flows without dissipation in a superconductor. Under certain conditions, an electric current can also flow without dissipation in microscopically small non-superconducting metals. However, currents in such perfect conductors are not called supercurrents, but persistent currents.
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https://en.wikipedia.org/wiki/Kapla
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Kapla is a construction set for children and adults. The sets consist only of identical wood planks measuring 11.7 cm x 2.34 cm x 0.78 cm. This 15:3:1 ratio of length:width:thickness is different than the dimensions used for traditionally proportioned building blocks (such as unit blocks), and are used for building features such as lintels, roofs and floors. They are known for their stability in the absence of fastening devices.
Name origin
"KAPLA" is an abbreviated form of the Dutch phrase "kabouter plankjes," which means "Gnome Planks."
History
KAPLA was invented in 1987 by Dutchman Tom van der Bruggen. A student of art history, Van der Bruggen had hopes of building a castle from an early age. Inspired by an old abandoned farm on the river Tarn in the South of France, Van der Bruggen converted the farm into his dream castle, complete with carriage entrance, fountains, and towers. To help him visualize the finished construction of his castle, Tom van der Bruggen used wooden blocks, but soon realized that they would not be suitable for certain aspects of the construction, such as the lintels, roofs and floors.
Assembly
KAPLA requires no glue, screws or clips to fix the planks. Each plank is placed one on top of the other, and held in place by weight and balance alone.
There are 3 possible ways to use Kapla planks:
Flat
On the side
Standing up (vertically)
Also, similar KAPLA constructions can create different assemblages:
Piled up as bricks: embedding
Piled up as spiral stairs: stacking
KAPLA is intended for children to safely build, create and experiment by using their imagination.
Varieties
KAPLA bricks are made of pine wood and are available in many different colors. They are sold in sets ranging in size from 40 to 1000 pieces.
Construction and art
KAPLA has created four educational art books, intended to inspire children who use their products.
They are meant to encourage the use of geometry, physics and technology, while exposing children to the w
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https://en.wikipedia.org/wiki/Post-Newtonian%20expansion
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In general relativity, post-Newtonian expansions (PN expansions) are used for finding an approximate solution of Einstein field equations for the metric tensor. The approximations are expanded in small parameters that express orders of deviations from Newton's law of universal gravitation. This allows approximations to Einstein's equations to be made in the case of weak fields. Higher-order terms can be added to increase accuracy, but for strong fields sometimes it is preferable to solve the complete equations numerically. This method is a common mark of effective field theories. In the limit, when the small parameters are equal to 0, the post-Newtonian expansion reduces to Newton's law of gravity.
Expansion in 1/c2
The post-Newtonian approximations are expansions in a small parameter, which is the ratio of the velocity of the matter that creates the gravitational field, to the speed of light, which in this case is more precisely called the speed of gravity. In the limit, when the fundamental speed of gravity becomes infinite, the post-Newtonian expansion reduces to Newton's law of gravity. A systematic study of post-Newtonian expansions within hydrodynamic approximations was developed by Subrahmanyan Chandrasekhar and his colleagues in the 1960s.
Expansion in h
Another approach is to expand the equations of general relativity in a power series in the deviation of the metric from its value in the absence of gravity.
To this end, one must choose a coordinate system in which the eigenvalues of all have absolute values less than 1.
For example, if one goes one step beyond linearized gravity to get the expansion to the second order in h:
Expansions based only on the metric, independently from the speed, are called post-Minkowskian expansions (PM expansions).
Uses
The first use of a PN expansion (to first order) was made by Albert Einstein in calculating the perihelion precession of Mercury's orbit. Today, Einstein's calculation is recognized as a common exampl
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https://en.wikipedia.org/wiki/Tunica%20albuginea%20of%20testis
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The tunica albugine is a dense, blue-white layer of fibrous tissue surrounding the testis. It is the middle of three enveloppes forming the capsule of the testis; it is deep to the visceral layer of tunica vaginalis, and superficial to the tunica vasculosa testis (vascular layer of testis).
The connective tissue of the tunica albuginea testis extends into the substance of the testis to form fibrous partitions - the septa testis. At the posterior aspect of the testis (where the serosa of testis is deficient to allow for the attachment of the epididymis), the tunica albuginea extends into the testis to form the mediastinum testis.
Anatomy
It is thicker than the tunica albuginea of the ovary.
Histology
It is composed of bundles of white fibrous connective tissue (from which it derives its name albuginea) which interlace in every direction.
Additional images
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https://en.wikipedia.org/wiki/Shide%20%28Shinto%29
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are zigzag-shaped paper streamers, often seen attached to or to demarcate holy spaces, and used in Shinto rituals in Japan. They are usually found adorning doorways, shrine buildings, and kamidana.
The origins of shide are traced to the yūshide, a thread made from the bark of Broussonetia x kazinoki mentioned in the Kojiki. There are different styles of folding shide. One method requires placing the paper zigzags in a cut slit on a stick, creating a ritual object known as a gohei or heihaku. A gohei is an offering to kami that can be seen on kamidana altars and inside the main building of a Shinto shrine.
A common purification ritual uses a , a wooden stick with linen or paper shide attached at the top. A Shinto priest waves the over a person, item, or newly bought property, such as a building or a car. The wand is waved at a slow and rhythmic pace, but with a little force so that the strips make a rustling noise on each pass of the wand. For new properties, a similar ritual known as (lit. "calming the land") is performed with a within an enclosed part of the land (enclosed by ).
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https://en.wikipedia.org/wiki/Robert%20S.%20Boyer
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Robert Stephen Boyer is an American retired professor of computer science, mathematics, and philosophy at The University of Texas at Austin. He and J Strother Moore invented the Boyer–Moore string-search algorithm, a particularly efficient string searching algorithm, in 1977. He and Moore also collaborated on the Boyer–Moore automated theorem prover, Nqthm, in 1992. Following this, he worked with Moore and Matt Kaufmann on another theorem prover called ACL2.
Publications
Boyer has published extensively, including the following books:
A Computational Logic Handbook, with J S. Moore. Second Edition. Academic Press, London, 1998.
Automated Reasoning: Essays in Honor of Woody Bledsoe, editor. Kluwer Academic, Dordrecht, The Netherlands, 1991.
A Computational Logic Handbook, with J S. Moore. Academic Press, New York, 1988.
The Correctness Problem in Computer Science, editor, with J S. Moore. Academic Press, London, 1981.
A Computational Logic, with J S. Moore. Academic Press, New York, 1979.
See also
Boyer–Moore majority vote algorithm
QED manifesto
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https://en.wikipedia.org/wiki/Speaker%20terminal
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A speaker terminal is a type of electrical connector often used for interconnecting speakers and audio power amplifiers.
The terminals are used in pairs with each of the speaker cable's two wires being connected to one terminal in the pair. Since speaker connections are polarized, the terminals are typically color-coded so that the positive wire connects to the red and the negative to the black terminal.
The terminal consists of a spring-loaded metallic pincher that opens when the lever is pressed, and when released will tightly grip the conductor which has been inserted into it. This type of terminal is popular because it does not require any special connector to be applied to the end of the wire; instead, the wire is simply stripped of insulation on its end and inserted into the terminal. This terminal may be used with a variety of wire gauges as well as with either solid core or stranded wires.
DIY projects sometimes reuse speaker terminals for other applications using bare wire leads.
See also
Banana connector
Binding post
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https://en.wikipedia.org/wiki/Iliolumbar%20artery
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The iliolumbar artery is the first branch of the posterior trunk of the internal iliac artery.
Structure
The iliolumbar artery is the first branch of the posterior trunk of the internal iliac artery. It turns upward behind the obturator nerve and the external iliac artery and vein, to the medial border of the psoas major muscle, behind which it divides into:
Lumbar branch of iliolumbar artery
Iliac branch of iliolumbar artery
Anastomoses
1. Last lumbar→iliolumbar
2. Lateral sacral↔lateral sacral
3. Middle sacral→lateral sacral
4. Superior hemorrhoidal→middle hemorrhoidal
5. Medial femoral circumflex→inferior gluteal
6. Medial femoral circumflex↔obturator
7. Lateral femoral circumflex→superior gluteal
8. Deep iliac circumflex→superior gluteal
9. Deep iliac circumflex→external iliac
10. Last lumbar→superior gluteal
11. Last lumbar→deep iliac circumflex
12. Iliolumbar→deep iliac circumflex.
Additional Images
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https://en.wikipedia.org/wiki/Superior%20gluteal%20artery
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The superior gluteal artery is the terminal branch of the posterior division of the internal iliac artery. It exits the pelvis through the greater sciatic foramen before splitting into a superficial branch and a deep branch.
Structure
Origin
The superior gluteal artery is the largest and final branch of the internal iliac artery. It branches from the posterior division of the internal iliac artery; it represents the continuation of the posterior division.
Course, relations and branches
It is a short artery. It passes posterior-ward between the lumbosacral trunk and the first sacral nerve (S1). Within the pelvis, it gives branches to the iliacus, piriformis, and obturator internus muscles. Just prior to exiting the pelvic cavity, it also gives off a nutrient artery which enters the ilium.
It exits the pelvis through the greater sciatic foramen superior to the piriformis muscle, then promptly divides into a superficial branch and a deep branch.
Superficial branch
The superficial branch passes over the piriformis muscle. It enters the deep surface of the gluteus maximus muscle, and divides into numerous branches. Some branches supply the muscle and anastomose with the inferior gluteal artery, while others perforate its tendinous origin, and supply the integument covering the posterior surface of the sacrum, anastomosing with the posterior branches of the lateral sacral arteries. The superficial branch also supplies the skin over the origin of the gluteus maximus muscle.
Deep branch
The deep branch passes deep to the gluteus medius. It almost immediately subdivides into the superior and inferior divisions.
The deep branch supplies the gluteus medius, gluteus minimus, and tensor fasciae latae muscles, as well as the hip joint.
Superior division
The superior division continues the original course of the vessel, passing along the superior border of the gluteus minimus muscle to the anterior superior spine of the ilium (ASIS), anastomosing with the deep iliac c
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https://en.wikipedia.org/wiki/Site-specific%20recombinase%20technology
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Site-specific recombinase technologies are genome engineering tools that depend on recombinase enzymes to replace targeted sections of DNA.
History
In the late 1980s gene targeting in murine embryonic stem cells (ESCs) enabled the transmission of mutations into the mouse germ line, and emerged as a novel option to study the genetic basis of regulatory networks as they exist in the genome. Still, classical gene targeting proved to be limited in several ways as gene functions became irreversibly destroyed by the marker gene that had to be introduced for selecting recombinant ESCs. These early steps led to animals in which the mutation was present in all cells of the body from the beginning leading to complex phenotypes and/or early lethality. There was a clear need for methods to restrict these mutations to specific points in development and specific cell types. This dream became reality when groups in the USA were able to introduce bacteriophage and yeast-derived site-specific recombination (SSR-) systems into mammalian cells as well as into the mouse.
Classification, properties and dedicated applications
Common genetic engineering strategies require a permanent modification of the target genome. To this end great sophistication has to be invested in the design of routes applied for the delivery of transgenes. Although for biotechnological purposes random integration is still common, it may result in unpredictable gene expression due to variable transgene copy numbers, lack of control about integration sites and associated mutations. The molecular requirements in the stem cell field are much more stringent. Here, homologous recombination (HR) can, in principle, provide specificity to the integration process, but for eukaryotes it is compromised by an extremely low efficiency. Although meganucleases, zinc-finger- and transcription activator-like effector nucleases (ZFNs and TALENs) are actual tools supporting HR, it was the availability of site-specific recombina
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https://en.wikipedia.org/wiki/Lateral%20sacral%20artery
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The lateral sacral arteries is an artery in the pelvis that arises from the posterior division of the internal iliac artery. It later splits into two smaller branches, a superior and an inferior.
Structure
The lateral sacral artery is the second branch of the posterior division of the internal iliac artery. It is a parietal branch.
Superior
The superior, of large size, passes medialward, and, after anastomosing with branches from the middle sacral, enters the first or second anterior sacral foramen, supplies branches to the contents of the sacral canal, and, escaping by the corresponding posterior sacral foramen, is distributed to the skin and muscles on the dorsum of the sacrum, anastomosing with the superior gluteal.
Inferior
The inferior runs obliquely across the front of the piriformis and the sacral nerves to the medial side of the anterior sacral foramina, descends on the front of the sacrum, and anastomoses over the coccyx with the middle sacral and opposite lateral sacral artery.
In its course it gives off branches, which enter the anterior sacral foramina; these, after supplying the contents of the sacral canal, escapes by the posterior sacral foramina, and are distributed to the muscles and skin on the dorsal surface of the sacrum, anastomosing with the gluteal arteries.
Function
The lateral sacral arteries supplies oxygenated blood to the cauda equina.
See also
Median sacral artery
Additional images
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https://en.wikipedia.org/wiki/Vaginal%20artery
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The vaginal artery is an artery in females that supplies blood to the vagina and the base of the bladder.
Structure
The vaginal artery is usually a branch of the internal iliac artery. Some sources say that the vaginal artery can arise from the uterine artery, but the phrase vaginal branches of uterine artery is the term for blood supply to the vagina coming from the uterine artery.
The vaginal artery is frequently represented by two or three branches. These descend to the vagina, supplying its mucous membrane. They anastomose with branches from the uterine artery. It can send branches to the bulb of the vestibule, the fundus of the bladder, and the contiguous part of the rectum.
Function
The vaginal artery supplies oxygenated blood to the muscular wall of the vagina, along with the uterine artery and the internal pudendal artery. It also supplies the cervix, along with the uterine artery.
Other animals
In horses, the vaginal artery may haemorrhage after birth, which can cause death.
See also
Uterine artery
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https://en.wikipedia.org/wiki/Inferior%20gluteal%20artery
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The inferior gluteal artery (sciatic artery) is a terminal branch of the anterior trunk of the internal iliac artery. It exits the pelvis through the greater sciatic foramen. It is distributed chiefly to the buttock and the back of the thigh.
Anatomy
Origin
It is the smaller of the two terminal branches of the anterior trunk of the internal iliac artery.
Course
It passes posterior-ward within parietal pelvic fascia. It travels in between the S1 nerve and S2 (or S2-S3) nerve(s). It descends upon the nerves of the sacral plexus and the piriformis muscle, posterior to the internal pudendal artery. It passes through the inferior part of the greater sciatic foramen. It exits the pelvis inferior to the piriformis muscle, between piriformis muscle and coccygeus muscle.
It then descends in the interval between the greater trochanter of the femur and tuberosity of the ischium. It is accompanied by the sciatic nerve and the posterior femoral cutaneous nerves, and covered by the gluteus maximus. It is situated medial to the sciatic nerve. It continues down the back of the thigh, supplying the skin, and anastomosing with branches of the perforating arteries.
Distribution
The inferior gluteal artery provides arterial supply to the gluteus maximus, obturator internus, quadratus femoris, and (the superior parts of) the hamstring muscles (semimembranosus, semitendinosus, and biceps femoris muscles).
Anastomoses
It forms anastomoses with the superior gluteal artery. It frequently participates in the formation of the cruciate anastomosis of the thigh.
Additional images
See also
Superior gluteal artery
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https://en.wikipedia.org/wiki/Obturator%20artery
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The obturator artery is a branch of the internal iliac artery that passes antero-inferiorly (forwards and downwards) on the lateral wall of the pelvis, to the upper part of the obturator foramen, and, escaping from the pelvic cavity through the obturator canal, it divides into an anterior branch and a posterior branch.
Structure
In the pelvic cavity this vessel is in relation, laterally, with the obturator fascia; medially, with the ureter, ductus deferens, and peritoneum; while a little below it is the obturator nerve.
The obturator artery usually arises from the internal iliac artery. Inside the pelvis the obturator artery gives off iliac branches to the iliac fossa, which supply the bone and the Iliacus, and anastomose with the ilio-lumbar artery; a vesical branch, which runs backward to supply the bladder; and a pubic branch, which is given off from the vessel just before it leaves the pelvic cavity.
The pubic branch ascends upon the back of the pubis, communicating with the corresponding vessel of the opposite side, and with the inferior epigastric artery.
After passing through the obturator canal and outside of the pelvis, the obturator artery divides at the upper margin of the obturator foramen, into an anterior branch and a posterior branch of the obturator artery which encircle the foramen under cover of the obturator externus.
Anterior branch
The anterior branch of the obturator artery is a small artery in the thigh and runs forward on the outer surface of the obturator membrane and then curves downward along the anterior margin of the obturator foramen.
It distributes branches to the obturator externus, pectineus, adductors, and gracilis muscle, and anastomoses with the posterior branch and with the medial femoral circumflex artery.
Posterior branch
The posterior branch of the obturator artery is a small artery in the thigh and follows the posterior margin of the foramen and turns forward on the inferior ramus of the ischium, where it anastomoses
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https://en.wikipedia.org/wiki/Superior%20vesical%20artery
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The superior vesical artery supplies numerous branches to the upper part of the bladder. This artery often also gives branches to the vas deferens and can provide minor collateral circulation for the testicles.
Anatomy
The superior vesical artery is a branch of the umbilical artery. The vesiculo-prostatic artery usually arises from the superior vesical artery in men.
Distribution
Other branches supply the ureter.
Variation
The middle vesical artery, usually a branch of the superior vesical artery, is distributed to the fundus of the bladder and the seminal vesicles. This artery is not usually described in modern anatomy textbooks. Instead, it is described that the superior vesical artery may exist as multiple vessels that arise from a common origin.
Development
The first part of the superior vesical artery represents the terminal section of the previous portion of the umbilical artery (fetal hypogastric artery).
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https://en.wikipedia.org/wiki/Prairie%20restoration
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Prairie restoration is a conservation effort to restore prairie lands that were destroyed due to industrial, agricultural, commercial, or residential development. The primary aim is to return areas and ecosystems to their previous state before their depletion.
In the United States, after the Black Hawk War had subsided in the mid-1830s, settlers from northern Europe and north east of the US made a home for themselves. They plowed up the tallgrasses and wild flowers in the area. By 1849 most specie of prairie grass had disappeared to make room for crops (i.e.: soybeans, corn, etc.). Restored prairies and the grasses that survived the 1800 plowing represent only a fragment of the abundant verdure that once covered he midsection of North America from western Ohio to the Rockies and from southern Canada to Texas. As an example, the U.S. state of Illinois alone once held over 35,000 square miles (91,000 km2) of prairie land and now just 3 square miles (7.8 km2) of that original prairie land is left. The over farming of this land as well as periods of drought and its exposure to the elements (no longer bound together by the tall grasses) was responsible for the Dust Bowls in the 1930s.
Issues of erosion, and waning biodiversity have arisen in areas once populated by prairie grass species. So in efforts of restoration, in Europe, when restoring previous crop land with prairie grasses, the most frequently used techniques involve: spontaneous succession, sowing seed mixtures, transfer of plant material, topsoil removal and transfer. When maintaining these tall grasses, prescribed fire is a popular method. It encourages taller and stronger regrowth as well as the recycling of nutrients in the soil.
Although not fully able to restore the full diversity of an area, restoration efforts aid the thriving of the natural ecosystems. This is further improved by the specific reintroduction of key organisms from the native plants microbiome. Prairie soil also effectively stores carb
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https://en.wikipedia.org/wiki/Perineal%20artery
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The perineal artery (superficial perineal artery) arises from the internal pudendal artery, and turns upward, crossing either over or under the superficial transverse perineal muscle, and runs forward, parallel to the pubic arch, in the interspace between the bulbospongiosus and ischiocavernosus muscles, both of which it supplies, and finally divides into several posterior scrotal branches which are distributed to the skin and dartos tunic of the scrotum.
As it crosses the superficial transverse perineal muscle it gives off the transverse perineal artery which runs transversely on the cutaneous surface of the muscle, and anastomoses with the corresponding vessel of the opposite side and with the perineal and inferior hemorrhoidal arteries.
It supplies the transverse perineal muscles and the structures between the anus and the urethral bulb.
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https://en.wikipedia.org/wiki/Wi-Fi%20calling
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Wi-Fi calling refers to mobile phone voice calls and data that are made over IP networks using Wi-Fi, instead of the cell towers provided by cellular networks. Using this feature, compatible handsets are able to route regular cellular calls through a wireless LAN (Wi-Fi) network with broadband Internet, while seamlessly change connections between the two where necessary. This feature makes use of the Generic Access Network (GAN) protocol, also known as Unlicensed Mobile Access (UMA).
Essentially, GAN/UMA allows cell phone packets to be forwarded to a network access point over the internet, rather than over-the-air using GSM/GPRS, UMTS or similar. A separate device known as a "GAN Controller" (GANC) receives this data from the Internet and feeds it into the phone network as if it were coming from an antenna on a tower. Calls can be placed from or received to the handset as if it were connected over-the-air directly to the GANC's point of presence; the system is essentially invisible to the network as a whole. This can be useful in locations with poor cell coverage where some other form of internet access is available, especially at the home or office. The system offers seamless handoff, so the user can move from cell to Wi-Fi and back again with the same invisibility that the cell network offers when moving from tower to tower.
Since the GAN system works over the internet, a UMA-capable handset can connect to their service provider from any location with internet access. This is particularly useful for travellers, who can connect to their provider's GANC and make calls into their home service area from anywhere in the world. This is subject to the quality of the internet connection, however, and may not work well over limited bandwidth or long-latency connection. To improve quality of service (QoS) in the home or office, some providers also supply a specially programmed wireless access point that prioritizes UMA packets. Another benefit of Wi-Fi calling is that mob
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https://en.wikipedia.org/wiki/Inferior%20rectal%20artery
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The inferior rectal artery (inferior hemorrhoidal artery) is an artery that supplies blood to the lower third of the anal canal below the pectinate line.
Structure
The inferior rectal artery arises from the internal pudendal artery as it passes above the ischial tuberosity.
Piercing the wall of the pudendal canal, it divides into two or three branches which cross the ischioanal fossa, and are distributed to the muscles and integument of the anal region, and send offshoots around the lower edge of the gluteus maximus to the skin of the buttock.
They anastomose with the corresponding vessels of the opposite side, with the superior and middle rectal arteries, and with the perineal artery.
Function
The inferior rectal artery supplies oxygenated blood to the anal sphincter and the lower third of the anal canal below the pectinate line.
Additional images
See also
Superior rectal artery
Middle rectal artery
Inferior rectal nerve
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https://en.wikipedia.org/wiki/Urethral%20artery
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The urethral artery arises from the internal pudendal artery a branch of the internal iliac artery. The internal pudendal artery has numerous branches including the artery of the bulb of the penis immediately before the urethral and the dorsal artery of the penis more distally.
In the male it penetrates the perineal membrane and provides blood to the urethra and nearby erectile tissue to the glans. In the female, the urethral artery serves the analogous structures. Because the female urethra is so much shorter than the male, this structure is often impossible to find on a female cadaver.
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https://en.wikipedia.org/wiki/History%20of%20gravitational%20theory
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In physics, theories of gravitation postulate mechanisms of interaction governing the movements of bodies with mass. There have been numerous theories of gravitation since ancient times. The first extant sources discussing such theories are found in ancient Greek philosophy. This work was furthered through the Middle Ages by Indian, Islamic, and European scientists, before gaining great strides during the Renaissance and Scientific Revolution—culminating in the formulation of Newton's law of gravity. This was superseded by Albert Einstein's theory of relativity in the early 20th century.
Greek philosopher Aristotle () found that objects immersed in a medium tend to fall at speeds proportional to their weight. Vitruvius () understood that objects fall based on their specific gravity. In the 6th century CE, Byzantine Alexandrian scholar John Philoponus modified the Aristotelian concept of gravity with the theory of impetus. In the 7th century, Indian astronomer Brahmagupta spoke of gravity as an attractive force. In the 14th century, European philosophers Jean Buridan and Albert of Saxony—who were influenced by certain Islamic scholars—developed the theory of impetus and linked it to the acceleration and mass of objects. Albert also developed a law of proportion regarding the relationship between the speed of an object in free fall and the time elapsed.
Italians of the 16th century found that objects in free fall tend to accelerate equally. In 1632, Galileo Galilei put forth the basic principle of relativity. The existence of the gravitational constant was explored by various researchers from the mid-17th century, helping Isaac Newton formulate his law of universal gravitation. Newton's classical mechanics were superseded in the early 20th century, when Einstein developed the special and general theories of relativity. The hypothetical force carrier of gravity remains an outlier in the search for a theory of everything, for which various models of quantum gravity ar
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https://en.wikipedia.org/wiki/Atom%20optics
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Atom optics (or atomic optics) "refers to techniques to manipulate the trajectories and exploit the wave properties
of neutral atoms". Typical experiments employ beams of cold, slowly moving neutral atoms, as a special case of a particle beam.
Like an optical beam, the atomic beam may exhibit diffraction and interference, and can be focused with a Fresnel zone plate or a concave atomic mirror.
For comprehensive overviews of atom optics, see the 1994 review by Adams, Sigel, and Mlynek or the 2009 review by Cronin, Jörg, and Pritchard. More bibliography about Atom Optics can be found at the Resource Letter. For quantum atom optics see the 2018 review by Pezzè Smerzi Oberthaler Schmied.
History
Interference of atom matter waves was first observed by Esterman and Stern in 1930, when a Na beam was diffracted off a surface of NaCl. The short de Broglie wavelength of atoms prevented progress for many years until two technological breakthroughs revived interest: microlithography allowing precise small devices and laser cooling allowing atoms to be slowed, increasing their de Broglie wavelength.
Until 2006, the resolution of imaging systems based on atomic beams was not better than that of an optical microscope,
mainly due to the poor performance of the focusing elements. Such elements use small numerical aperture;
usually, atomic mirrors use grazing incidence, and the reflectivity drops drastically with increase of the
grazing angle; for efficient normal reflection, atoms should be ultracold, and
dealing with such atoms usually involves magnetic, magneto-optical or optical traps.
Recent scientific publications about Atom Nano-Optics, evanescent field lenses
and ridged mirrors
show significant improvement since the beginning of the 21st century. In particular, an
atomic hologram can be realized.
See also
Atomic nanoscope
Electron microscope
Quantum reflection
Atom interferometer
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