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Transversal (combinatorics)-Relation to matching and covering-One can construct a bipartite graph in which the vertices on one side are the sets, the vertices on the other side are the elements, and the edges connect a set to the elements it contains. Then, a transversal (defined as a system of distinct representatives...
milkshake721/2.1M-wiki-STEM
Transversal (combinatorics)-Examples-In group theory, given a subgroup H of a group G, a right (respectively left) transversal is a set containing exactly one element from each right (respectively left) coset of H. In this case, the "sets" (cosets) are mutually disjoint, i.e. the cosets form a partition of the group. A...
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Transversal (combinatorics)-Examples-Another instance of a partition-based transversal occurs when one considers the equivalence relation known as the (set-theoretic) kernel of a function, defined for a function f with domain X as the partition of the domain ker := {{y∈X∣f(x)=f(y)}∣x∈X} . which partitions the domain ...
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Transversal (combinatorics)-Common Transversals-A common transversal of the collections A and B (where |A|=|B|=n ) is a set that is a transversal of both A and B. The collections A and B have a common transversal if and only if, for all I,J⊂{1,...,n} ,|(⋃i∈IAi)∩(⋃j∈JBj)|≥|I|+|J|−n
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Transversal (combinatorics)-Generalizations-A partial transversal is a set containing at most one element from each member of the collection, or (in the stricter form of the concept) a set with an injection from the set to C. The transversals of a finite collection C of finite sets form the basis sets of a matroid, the...
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Transversal (combinatorics)-Category theory-In the language of category theory, a transversal of a collection of mutually disjoint sets is a section of the quotient map induced by the collection.
milkshake721/2.1M-wiki-STEM
Transversal (combinatorics)-Computational complexity-The computational complexity of computing all transversals of an input family of sets has been studied, in particular in the framework of enumeration algorithms.
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Statistical assumption-Statistical assumption-Statistics, like all mathematical disciplines, does not infer valid conclusions from nothing. Inferring interesting conclusions about real statistical populations almost always requires some background assumptions. Those assumptions must be made carefully, because incorrect...
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Statistical assumption-Classes of assumptions-There are two approaches to statistical inference: model-based inference and design-based inference. Both approaches rely on some statistical model to represent the data-generating process. In the model-based approach, the model is taken to be initially unknown, and one of ...
milkshake721/2.1M-wiki-STEM
Statistical assumption-Classes of assumptions-Statistical assumptions can be put into two classes, depending upon which approach to inference is used. Model-based assumptions. These include the following three types: Distributional assumptions. Where a statistical model involves terms relating to random errors, assumpt...
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Statistical assumption-Checking assumptions-Given that the validity of any conclusion drawn from a statistical inference depends on the validity of the assumptions made, it is clearly important that those assumptions should be reviewed at some stage. Some instances—for example where data are lacking—may require that re...
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Addressable heap-Addressable heap-In computer science, an addressable heap is an abstract data type. Specifically, it is a mergeable heap supporting access to the elements of the heap via handles (also called references). It allows the key of the element referenced by a particular handle to be removed or decreased.
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Addressable heap-Definition-An addressable heap supports the following operations: Make-Heap(), creating an empty heap. Insert(H,x), inserting an element x into the heap H, and returning a handle to it. Min(H), returning a handle to the minimum element, or Nil if no such element exists. Extract-Min(H), extracting and r...
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Addressable heap-Examples-Examples of addressable heaps include: Fibonacci heaps Binomial heapsA more complete list with performance comparisons can be found here.
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Zeugma and syllepsis-Zeugma and syllepsis-In rhetoric, zeugma ( (listen); from the Ancient Greek ζεῦγμα, zeûgma, lit. "a yoking together") and syllepsis (; from the Ancient Greek σύλληψις, sullēpsis, lit. "a taking together") are figures of speech in which a single phrase or word joins different parts of a sentence.
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Zeugma and syllepsis-Definition-In current usage, there are multiple and sometimes conflicting definitions for zeugma and syllepsis. This article categorizes these two figures of speech into four types, based on four definitions: Type 1 Grammatical syllepsis (sometimes also called zeugma): where a single word is used i...
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Zeugma and syllepsis-Definition-"He works his work, I mine"This quote from Alfred Tennyson's poem "Ulysses" is ungrammatical from a grammarian's viewpoint, because "works" does not grammatically agree with "I": the sentence "I works mine" would be ungrammatical. On the other hand, Tennyson's two sentences could be take...
milkshake721/2.1M-wiki-STEM
Zeugma and syllepsis-Definition-Type 2 Zeugma (often also called syllepsis, or semantic syllepsis): a single word is used with two other parts of a sentence but must be understood differently in relation to each. Example: "He took his hat and his leave." The type of figure is grammatically correct but creates its effec...
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Zeugma and syllepsis-Definition-"Here Thou, great Anna! whom three Realms obey,Dost sometimes Counsel take – and sometimes Tea." (Alexander Pope, The Rape of the Lock, Canto III) "Miss Bolo [...] went straight home, in a flood of tears and a sedan-chair." (Charles Dickens, The Pickwick Papers, Chapter 35) “They sought ...
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Zeugma and syllepsis-Definition-"He watches afternoon repeats and the food he eats." (Blur, "Country House") "You held your breath and the door for me." (Alanis Morissette, "Head Over Feet") "I took the podium and my second trophy of the evening." (Samuel R. Delany, "Racism and Science Fiction") “My blood sugar fell dr...
milkshake721/2.1M-wiki-STEM
Zeugma and syllepsis-Definition-"The boy swallowed milk and kisses," as contrasted with "The boy swallowed kisses and milk".The opposite process, in which the first noun expresses a figurative meaning and the second a more literal meaning, tends to create a comic effect: "and she feeds me love and tenderness and macaro...
milkshake721/2.1M-wiki-STEM
Zeugma and syllepsis-Definition-Vicit pudorem libido timorem audacia rationem amentia. (Cicero, Pro Cluentio, VI.15) "Lust conquered shame; audacity, fear; madness, reason."The more usual way of phrasing this would be "Lust conquered shame, audacity conquered fear, and madness conquered reason." The sentence consists o...
milkshake721/2.1M-wiki-STEM
Zeugma and syllepsis-Definition-Histories make men wise; poets, witty; the mathematics, subtle; natural philosophy, deep; moral, grave; logic and rhetoric, able to contend. (Francis Bacon).The more usual way of phrasing this would be "Histories make men wise, poets make them witty, mathematics make them subtle, natural...
milkshake721/2.1M-wiki-STEM
Zeugma and syllepsis-Definition-Type 4 A special case of semantic syllepsis occurs when a word or phrase is used both in its figurative and literal sense at the same time. Then, it is not necessary for the governing phrase to relate to two other parts of the sentence. One example is in an advertisement for a transport ...
milkshake721/2.1M-wiki-STEM
Zeugma and syllepsis-Other types and related figures-There are several other definitions of zeugma that encompass other ways in which one word in a sentence can relate to two or more others. Even a simple construction like "this is easy and comprehensible" has been called a "zeugma without complication" because "is" go...
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Zeugma and syllepsis-Other types and related figures-Populus Romanus Numantiam delevit Kartaginem sustulit Corinthum disiecit Fregellas evertit. (Anon. Rhetorica ad Herennium. IV. xxvii.) The Roman people destroyed Numantia, razed Carthage, demolished Corinth, and overthrew Fregellae.
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Zeugma and syllepsis-Other types and related figures-"We shall pay any price, bear any burden, meet any hardship, support any friend, oppose any foe to assure the survival and the success of liberty." (Inaugural address of John F. Kennedy) Hypozeugma Hypozeugma or "adjunctions" (adiunctio) is used in a construction con...
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Zeugma and syllepsis-Other types and related figures-Assure yourself that Damon to his Pythias, Pylades to his Orestes, Titus to his Gysippus, Theseus to his Pyrothus, Scipio to his Laelius, was never found more faithful than Euphues will be to his Philautus. (John Lyly, Euphues) Prozeugma A prozeugma,synezeugmenon, or...
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Abney effect-Abney effect-The Abney effect or the purity-on-hue effect describes the perceived hue shift that occurs when white light is added to a monochromatic light source.The addition of white light will cause a desaturation of the monochromatic source, as perceived by the human observer. However, a less intuitive ...
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Abney effect-Abney effect-This variance of hue as a result of the addition of white light was first described by the English chemist and physicist Sir William de Wiveleslie Abney in 1909, although the date is commonly reported as 1910. A white light source can be created by the combination of red, blue, and green light...
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Abney effect-Chromaticity diagrams-Chromaticity diagrams are two-dimensional diagrams that plot the projection of the International Commission on Illumination (CIE) XYZ color space onto the (x, y) plane. The X, Y, Z values (or tristimulus values) are simply used as weightings to create new colors from the primary color...
milkshake721/2.1M-wiki-STEM
Abney effect-Physiology-The opponent process model of the visual system is composed of two chromatic neural channels and one achromatic neural channel. The chromatic channels consist of a red-green channel and a yellow-blue channel and transmit color information. The achromatic channel is responsible for luminance, or ...
milkshake721/2.1M-wiki-STEM
Abney effect-Colorimetric purity-The saturation, or degree of paleness of a color, is related to colorimetric purity. The equation for colorimetric purity is: P = L/(Lw + L). In this equation, L equals the luminance of the colored light stimulus, Lw is the luminance of the white light stimulus to be mixed with the colo...
milkshake721/2.1M-wiki-STEM
Abney effect-Hue discrimination-The term hue discrimination is used to describe the change in wavelength that must be obtained in order for the eye to detect a shift in hue. An expression λ + Δλ defines the required wavelength adjustment that must take place. A small (< 2 nm) change in wavelength causes most spectral c...
milkshake721/2.1M-wiki-STEM
Abney effect-History-The original article describing the Abney effect was published by Sir William de Wiveleslie Abney in Proceedings of the Royal Society of London, Series A in December 1909. He decided to do quantitative research following the discovery that the visual observations of color did not match the dominant...
milkshake721/2.1M-wiki-STEM
Abney effect-History-A color-measuring apparatus commonly used in experiments in the 1900s was used in conjunction with partially silvered mirrors to split one beam of light into two beams. This resulted in two beams of light parallel to one another having the same intensity and color. The beams of light were projected...
milkshake721/2.1M-wiki-STEM
Abney effect-Similar effect of bandwidth-While the nonlinearity of neural color-coding, as evidenced by the classical understanding of the Abney effect and its use of white light to particular wavelengths of light, has been thoroughly studied in the past, a new method was undertaken by researchers at the University of ...
milkshake721/2.1M-wiki-STEM
Abney effect-Miscellaneous facts-A patent for a color printer that claims to compensate for the Abney effect was published in 1995.The Abney effect must be taken into account when designing the cockpit for modern fighter planes. The colors viewed on the screen become desaturated when white light strikes the screen, so ...
milkshake721/2.1M-wiki-STEM
Abney effect-Modeling-The Abney effect is rarely described by known color appearance models. Of the many models Fairchild reviewed in Color Appearance Models (3 ed.), only the Hunt and ATD models predict the Abney effect.
milkshake721/2.1M-wiki-STEM
Precordium-Precordium-In anatomy, the precordium or praecordium is the portion of the body over the heart and lower chest.Defined anatomically, it is the area of the anterior chest wall over the heart. It is therefore usually on the left side, except in conditions like dextrocardia, where the individual's heart is on t...
milkshake721/2.1M-wiki-STEM
Precordium-Precordium-The precordium is naturally a cardiac area of dullness. During examination of the chest, the percussion note will therefore be dull. In fact, this area only gives a resonant percussion note in hyperinflation, emphysema or tension pneumothorax. Precordial chest pain can be an indication of a variet...
milkshake721/2.1M-wiki-STEM
Amantadine-Amantadine-Amantadine, sold under the brand name Gocovri among others, is a medication used to treat dyskinesia associated with parkinsonism and influenza caused by type A influenzavirus, though its use for the latter is no longer recommended due to widespread drug resistance. It acts as a nicotinic antagoni...
milkshake721/2.1M-wiki-STEM
Amantadine-Amantadine-Amantadine has a mild side effect profile. Common neurological side effects include drowsiness, light headedness, dizziness, and confusion. Due to its effects on the central nervous system, it is only with caution that it should be combined with additional CNS stimulants or anticholinergic drugs. ...
milkshake721/2.1M-wiki-STEM
Amantadine-Chemical structure-Amantadine (brand names Gocovri, Symadine, and Symmetrel) is the organic compound 1-adamantylamine or 1-aminoadamantane, which consists of an adamantane backbone with an amino group substituted at one of the four methyne positions. Rimantadine is a closely related adamantane derivative wit...
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Amantadine-Mechanism of action-Parkinson's disease The mechanism of its antiparkinsonian effect is poorly understood. Amantadine is a weak antagonist of the NMDA-type glutamate receptor, increases dopamine release, and blocks dopamine reuptake. Amantadine probably does not inhibit monoamine oxidase (MAO) enzyme. Moreov...
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Amantadine-Mechanism of action-Influenza The mechanisms for amantadine's antiviral and antiparkinsonian effects are unrelated. Amantadine targets the influenza A M2 ion channel protein. The M2 protein's function is to allow the intracellular virus to replicate (M2 also functions as a proton channel for hydrogen ions to...
milkshake721/2.1M-wiki-STEM
Amantadine-Pharmacokinetics-Amantadine is well absorbed orally. The onset of action is usually within 48 hours when used for parkinsonian syndromes, including dyskinesia. As plasma concentrations of amantadine increase, there is a greater risk for toxicity.Half-life elimination averages eight days in patients with end-...
milkshake721/2.1M-wiki-STEM
Amantadine-Medical uses-Parkinson's disease Amantadine is used to treat Parkinson's disease-related dyskinesia and drug-induced parkinsonism syndromes. Amantadine may be used alone or in combination with another anti-Parkinson's or anticholinergic drug. The specific symptoms targeted by amantadine therapy are dyskinesi...
milkshake721/2.1M-wiki-STEM
Amantadine-Medical uses-Influenza A Amantadine is not recommended for treatment or prophylaxis of influenza A in the United States. Amantadine has no effect preventing or treating influenza B infections. The US Centers for Disease Control and Prevention found 100% of seasonal H3N2 and 2009 pandemic flu samples were res...
milkshake721/2.1M-wiki-STEM
Amantadine-Medical uses-Extra-pyramidal side effects An extended release formulation is used to treat levodopa-induced dyskinesia in patients with Parkinson's disease. The WHO recommends the use of amantadine as a combination therapy to reduce levodopa side effects.
milkshake721/2.1M-wiki-STEM
Amantadine-Medical uses-Off-label uses Fatigue in multiple sclerosis A 2007 Cochrane literature review concluded that there was no overall evidence supporting the use of amantadine in treating fatigue in patients with MS. A follow-up 2012 Cochrane review stated that there may be some amantadine-induced improvement in f...
milkshake721/2.1M-wiki-STEM
Amantadine-Medical uses-Awareness in patients with disorders of consciousness Disorders of consciousness (DoC) include coma, vegetative state (VS), and minimally conscious state (MCS). Amantadine has been shown to increase the rate of emergence from a MCS, defined by consistent demonstration of interactive communicatio...
milkshake721/2.1M-wiki-STEM
Amantadine-Medical uses-Neuroplasticity and overall functional recovery in patients with brain injury In various studies, amantadine and memantine have been shown to accelerate the rate of recovery from a brain injury. The time-limited window following a brain injury is characterized by neuroplasticity, or the capacity...
milkshake721/2.1M-wiki-STEM
Amantadine-Medical uses-Attention deficit hyperactivity disorder A 2010 randomized clinical trial showed similar improvements in ADHD symptoms in children treated with amantadine as in those treated with methylphenidate, with less frequent side effects. A 2021 retrospective study showed that amantadine may serve as an ...
milkshake721/2.1M-wiki-STEM
Amantadine-Adverse effects-Amantadine is generally well tolerated and has a mild side-effect profile.
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Amantadine-Adverse effects-Neurological Side effects include drowsiness (especially while driving), lightheadedness, falls, and dizziness. Patients on amantadine should avoid combination with other central nervous system (CNS) depressing agents, such as alcohol. Excessive alcohol usage may increase the potential for CN...
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Amantadine-Adverse effects-Cardiovascular Amantadine may cause orthostatic hypotension, syncope, and peripheral edema. Gastrointestinal Amantadine has also been associated with dry mouth and constipation. Skin Rare cases of skin rashes, such as Stevens–Johnson syndrome and livedo reticularis have also been reported in ...
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Amantadine-Adverse effects-Kidney Amantadine inhibits the kidney's active-transport removal and transfer of creatinine from blood to urine, which normally occurs in the proximal tubules of the nephrons. The active-transport removal mechanism accounts for about fifteen percent of creatinine clearance. Therefore, amantad...
milkshake721/2.1M-wiki-STEM
Amantadine-Adverse effects-Pregnancy and lactation Amantadine is Food and Drug Administration category C for pregnancy. Teratogenic effects have been observed in humans (case reports) and animal reproduction studies. Amantadine may also be present in breast milk and negatively alter breast milk production or excretion....
milkshake721/2.1M-wiki-STEM
Amantadine-Interactions-Amantadine may affect the central nervous system due to dopaminergic and anticholinergic properties. The mechanisms of action are not fully known. Because of the CNS effects, caution is required when prescribing additional CNS stimulants or anticholinergic drugs. Thus, concurrent use of alcohol ...
milkshake721/2.1M-wiki-STEM
Amantadine-Contraindications-Amantadine is contraindicated in persons with end stage kidney disease. The drug is renally cleared.Amantadine may have anticholinergic side effects. Thus, patients with an enlarged prostate or glaucoma should use with caution.Live attenuated vaccines are contraindicated while taking amanta...
milkshake721/2.1M-wiki-STEM
Amantadine-History-Influenza A Antiviral properties were first reported in 1963 at the University of Illinois Hospital in Chicago. In this amantadine trial study volunteer college students were exposed to a viral challenge. The group that received amantadine (100 milligrams 18 hours before viral challenge) had less Asi...
milkshake721/2.1M-wiki-STEM
Amantadine-History-Parkinson's disease An incidental finding in 1969 prompted investigations about amantadine's effectiveness for treating symptoms of Parkinson's disease. A woman with Parkinson's disease was prescribed amantadine to treat her influenza infection and reported her cogwheel rigidity and tremors improved....
milkshake721/2.1M-wiki-STEM
Amantadine-Veterinary misuse-In 2005, Chinese poultry farmers were reported to have used amantadine to protect birds against avian influenza. In Western countries and according to international livestock regulations, amantadine is approved only for use in humans. Chickens in China have received an estimated 2.6 billion...
milkshake721/2.1M-wiki-STEM
Plen-Plen-PLEN is a small desktop toy humanoid robot that can replicate complex human movements. It is controlled remotely by use of a Bluetooth enabled phone. When programmed, it is able to use a skateboard, rollerskates, pick up, kick and throw small things, and stand up if he tumbles to the floor. It does not featur...
milkshake721/2.1M-wiki-STEM
Plen-Plen-Videos of PLEN are being widely distributed and featured on sites such as YouTube, notably for its ability to perform roller skating and skateboard stunts. It performs these feats in a very lifelike fashion.
milkshake721/2.1M-wiki-STEM
Plen-Plen-PLEN is 9 inches (22.8 cm) tall, weighs 696 grams and is equipped with a 3 axis accelerometer to assist in balancing. It has 18 degrees of freedom and a 32bit ARM7 CPU. PLEN is powered by 6V-950mA NiMH rechargeable battery. The battery pack is on the robot's back and resembles a backpack. Its central position...
milkshake721/2.1M-wiki-STEM
Veress needle-Veress needle-A Veress needle or Veres needle is a spring-loaded needle used to create pneumoperitoneum for laparoscopic surgery. Of the three general approaches to laparoscopic access, the Veress needle technique is the oldest and most traditional.
milkshake721/2.1M-wiki-STEM
Veress needle-History-The tool was first developed in 1932 by János Veres(s) (1903–1979), a Hungarian internist working with tuberculosis patients. At the time, one of the mainstays of treatment was to collapse an infected lung and allow lesions to heal. The needle was introduced as a safer technique to give patients s...
milkshake721/2.1M-wiki-STEM
Veress needle-Description-Modern needles are 12 to 15 cm long, with an external diameter of 2 mm. The outer cannula consists of a beveled needle point for cutting through tissues of the abdominal wall. A spring-loaded, inner stylet is positioned within the outer cannula. This inner stylet has a dull tip to protect any ...
milkshake721/2.1M-wiki-STEM
Veress needle-Use-In a large survey of 155,987 gynecologic procedures and 17,216 general surgery procedures, the Veress needle technique was used in 78% of them. Gynecologists (81%) used the tool more often than general surgeons (48%) who are far more likely to use the open access technique.
milkshake721/2.1M-wiki-STEM
Veress needle-Iatrogenics-Several studies have pointed out that for various laparoscopic surgical applications (such as cholecystectomy, groin hernia repairs and appendectomies), creating pneumoperitoneum by using a Veress needle is not always as safe and effective as other techniques (e.g. direct trocar insertion (DTI...
milkshake721/2.1M-wiki-STEM
Veress needle-Iatrogenics-Between the complications associated to this instrument it can be found: Injury to hollow viscous Bleeding Failure to achieve pneumoperitoneum Prepneumoperitoneum Biloma due to liver puncture. Vascular injury
milkshake721/2.1M-wiki-STEM
Ambiguous grammar-Ambiguous grammar-In computer science, an ambiguous grammar is a context-free grammar for which there exists a string that can have more than one leftmost derivation or parse tree. Every non-empty context-free language admits an ambiguous grammar by introducing e.g. a duplicate rule. A language that o...
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Ambiguous grammar-Ambiguous grammar-For computer programming languages, the reference grammar is often ambiguous, due to issues such as the dangling else problem. If present, these ambiguities are generally resolved by adding precedence rules or other context-sensitive parsing rules, so the overall phrase grammar is un...
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Ambiguous grammar-Examples-Trivial language The simplest example is the following ambiguous grammar (with start symbol A) for the trivial language that consists of only the empty string: A → A | ε…meaning that the nonterminal A can be derived to either itself again, or to the empty string. Thus the empty string has lef...
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Ambiguous grammar-Examples-This language also has an unambiguous grammar, consisting of a single production rule: A → ε…meaning that the unique production can produce only the empty string, which is the unique string in the language. In the same way, any grammar for a non-empty language can be made ambiguous by adding ...
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Ambiguous grammar-Examples-Unary string The regular language of unary strings of a given character, say 'a' (the regular expression a*), has the unambiguous grammar: A → aA | ε…but also has the ambiguous grammar: A → aA | Aa | εThese correspond to producing a right-associative tree (for the unambiguous grammar) or allo...
milkshake721/2.1M-wiki-STEM
Ambiguous grammar-Examples-Addition and subtraction The context free grammar A → A + A | A − A | ais ambiguous since there are two leftmost derivations for the string a + a + a: As another example, the grammar is ambiguous since there are two parse trees for the string a + a − a: The language that it generates, however...
milkshake721/2.1M-wiki-STEM
Ambiguous grammar-Examples-Concretely, in many languages one may write conditionals in two valid forms: the if-then form, and the if-then-else form – in effect, making the else clause optional:In a grammar containing the rules Statement → if Condition then Statement | if Condition then Statement else Statement | ... Co...
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Ambiguous grammar-Examples-some ambiguous phrase structures can appear. The expression if a then if b then s else s2 can be parsed as either if a then begin if b then s end else s2 or as if a then begin if b then s else s2 end depending on whether the else is associated with the first if or second if.
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Ambiguous grammar-Examples-This is resolved in various ways in different languages. Sometimes the grammar is modified so that it is unambiguous, such as by requiring an endif statement or making else mandatory. In other cases the grammar is left ambiguous, but the ambiguity is resolved by making the overall phrase gram...
milkshake721/2.1M-wiki-STEM
Ambiguous grammar-Examples-An unambiguous grammar with multiple derivations The existence of multiple derivations of the same string does not suffice to indicate that the grammar is ambiguous; only multiple leftmost derivations (or, equivalently, multiple parse trees) indicate ambiguity.
milkshake721/2.1M-wiki-STEM
Ambiguous grammar-Examples-For example, the simple grammar S → A + A A → 0 | 1 is an unambiguous grammar for the language { 0+0, 0+1, 1+0, 1+1 }. While each of these four strings has only one leftmost derivation, it has two different derivations, for example S ⇒ A + A ⇒ 0 + A ⇒ 0 + 0 and S ⇒ A + A ⇒ A + 0 ⇒ 0 + 0 Only ...
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Ambiguous grammar-Recognizing ambiguous grammars-The decision problem of whether an arbitrary grammar is ambiguous is undecidable because it can be shown that it is equivalent to the Post correspondence problem. At least, there are tools implementing some semi-decision procedure for detecting ambiguity of context-free ...
milkshake721/2.1M-wiki-STEM
Ambiguous grammar-Inherently ambiguous languages-While some context-free languages (the set of strings that can be generated by a grammar) have both ambiguous and unambiguous grammars, there exist context-free languages for which no unambiguous context-free grammar can exist. Such languages are called inherently ambigu...
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Ambiguous grammar-Inherently ambiguous languages-The union of {anbmcmdn∣n,m>0} with {anbncmdm∣n,m>0} is inherently ambiguous. This set is context-free, since the union of two context-free languages is always context-free. But Hopcroft & Ullman (1979) give a proof that any context-free grammar for this union language ...
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Interference filter-Interference filter-An interference filter or dichroic filter is an optical filter that reflects one or more spectral bands or lines and transmits others, while maintaining a nearly zero coefficient of absorption for all wavelengths of interest. An interference filter may be high-pass, low-pass, ban...
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Interference filter-Interference filter-An interference filter consists of multiple thin layers of dielectric material having different refractive indices. There also may be metallic layers. In its broadest meaning, interference filters comprise also etalons that could be implemented as tunable interference filters. In...
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Interference filter-Additional sources-This article incorporates public domain material from Federal Standard 1037C. General Services Administration. Archived from the original on 2022-01-22. M. Bass, Handbook of Optics (2nd ed.) pp. 42.89-42.90 (1995)
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Hydrogen dehydrogenase-Hydrogen dehydrogenase-In enzymology, a hydrogen dehydrogenase (EC 1.12.1.2) is an enzyme that catalyzes the chemical reaction H2 + NAD+ ⇌ H+ + NADHThus, the two substrates of this enzyme are H2 and NAD+, whereas its two products are H+ and NADH.
milkshake721/2.1M-wiki-STEM
Hydrogen dehydrogenase-Hydrogen dehydrogenase-This enzyme belongs to the family of oxidoreductases, specifically those acting on hydrogen as donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is hydrogen:NAD+ oxidoreductase. Other names in common use include H2:NAD+ oxidoreductase, NAD+-link...
milkshake721/2.1M-wiki-STEM
Multi Protocol File System-Multi Protocol File System-The Multi Protocol File System (MPFS) is a multi-path network filesystem technology developed and sold by EMC Corporation. MPFS is intended to allow hundreds to thousands of client computer nodes to access shared computer data with higher performance than convention...
milkshake721/2.1M-wiki-STEM
Multi Protocol File System-Description-MPFS technology is intended for HPC (High Performance Computing) environments in which multiple compute nodes require concurrent access to data sets. This technology can be used to store and access data for grid computing, where the individual computing power of many systems is co...
milkshake721/2.1M-wiki-STEM
Capital region-Capital region-A capital region, also called a capital district or capital territory, is a region or district surrounding the country's capital city. It is not always the official term for the region, but may sometimes be used as an informal synonym. Capital regions can exist for either national or subna...
milkshake721/2.1M-wiki-STEM
Douglas Wahlsten-Douglas Wahlsten-Douglas Leon Wahlsten (born October 13, 1943) is a Canadian neuroscientist, psychologist, and behavior geneticist. He is a professor emeritus of psychology at the University of Alberta. As of 2011, he was also a visiting professor at the University of North Carolina at Greensboro in No...
milkshake721/2.1M-wiki-STEM
U2 spliceosomal RNA-U2 spliceosomal RNA-U2 spliceosomal snRNAs are a species of small nuclear RNA (snRNA) molecules found in the major spliceosomal (Sm) machinery of virtually all eukaryotic organisms. In vivo, U2 snRNA along with its associated polypeptides assemble to produce the U2 small nuclear ribonucleoprotein (s...
milkshake721/2.1M-wiki-STEM
U2 spliceosomal RNA-U2 snRNA Recognition Elements-In Saccharomyces cerevisiae the U2 snRNA is associated with 18 polypeptides, seven of which are structural proteins common to all Sm class snRNPs. These non-specific structural proteins associate with Sm snRNAs through a highly conserved recognition sequence (AUnG,n = 4...
milkshake721/2.1M-wiki-STEM
U2 spliceosomal RNA-Primary and Secondary Structure-Although the sequence length of U2 snRNAs can vary by up to an order of magnitude across all eukaryotic organisms, all U2 snRNAs contain many phylogenetically constant regions particularly within the first 80 nucleotides downstream of the 5´ end where 85% of the posit...
milkshake721/2.1M-wiki-STEM
U2 spliceosomal RNA-Conformational Dynamics-The spliceosome is a dynamic molecular machine that undergoes several conformational rearrangements throughout assembly and splicing. Although many of the biochemical details surrounding spliceosomal rearrangements remains unclear, recent studies have visualized the formation...
milkshake721/2.1M-wiki-STEM