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https://en.wikipedia.org/wiki/Sound%20%28nautical%29
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In nautical terms, the word sound is used to describe the process of determining the depth of water in a tank or under a ship. Tanks are sounded to determine if they are full (for cargo tanks) or empty (to determine if a ship has been holed) and for other reasons. Soundings may also be taken of the water around a ship if it is in shallow water to aid in navigation.
Methods
Tanks may be sounded manually or with electronic or mechanical automated equipment. Manual sounding is undertaken with a sounding line- a rope with a weight on the end. Per the Code of Federal Regulations, most steel vessels with integral tanks are required to have sounding tubes and reinforcing plates under the tubes which the weight strikes when it reaches the bottom of the tank. Sounding tubes are steel pipes which lead upwards from the ships' tanks to a place on deck.
Electronic and mechanical automated sounding may be undertaken with a variety of equipment including float level sensors, capacitance sensors, sonar, etc.
See also
Depth sounding
Sources
Code of Federal Regulations, Title 46
Nautical terminology
Navigational aids
Oceanography
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https://en.wikipedia.org/wiki/Figments%20of%20Reality
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Figments of Reality: The Evolution of the Curious Mind (1997) is a book about the evolution of the intelligent and conscious human mind by biologist Jack Cohen and mathematician Ian Stewart.
Overview
In this book Cohen and Stewart give their ideas on how the sentient human being evolved. Various chapters discuss scientific and
philosophical ideas such as emergence and chaos, free will, perception versus reality, objectivity versus subjectivity, self-awareness, the ego and id, groupthink, and extelligence. A theme is that the traditional reductionist approach of trying to understand things as interaction of simpler things can not alone explain such complex concepts as intelligence or culture. To better understand them one has to consider also the context in which they have evolved and the fact that the evolution is a recursive process, often changing the context so that previously unseen evolutionary paths became available. The authors claim that intelligence is an inevitable result of letting evolution progress for long enough.
Topics are illustrated with humorous science fiction snippets dealing with a hypothetical alien intelligence, the Zarathustrians, whom Cohen and Stewart use as metaphors of the human mind itself, an alternative evolution story, and various philosophical concepts.
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https://en.wikipedia.org/wiki/Jean%20Gallier
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Jean Henri Gallier (born 1949) is a researcher in computational logic at the University of Pennsylvania, where he holds appointments in the Computer and Information Science Department and the Department of Mathematics.
Biography
Gallier was born January 5, 1949, in Nancy, France, and holds dual French and American citizenship. He earned his baccalauréat at the Lycée de Sèvres in 1966, and a degree in civil engineering at the École Nationale des Ponts et Chaussées in 1972.
He then moved to the University of California, Los Angeles for his graduate studies, earning a Ph.D. in computer science in 1978 under the joint supervision of Sheila Greibach and Emily Perlinski Friedman. His dissertation was entitled Semantics and Correctness of Classes of Deterministic and Nondeterministic Recursive Programs.
After postdoctoral study at the University of California, Santa Barbara, he joined the University of Pennsylvania Department of Computer and Information Science in 1978. At Pennsylvania, he was promoted to full professor in 1990, gained a secondary appointment to the Department of Mathematics in 1994, and directed the French Institute of Culture and Technology from 2001 to 2004.
Contributions
Gallier's most heavily cited research paper, with his student William F. Dowling, gives a linear time algorithm for Horn-satisfiability.
This is a variant of the Boolean satisfiability problem: its input is a Boolean formula in conjunctive normal form with at most one positive literal per clause, and the goal is to assign truth values to the variables of the formula to make the whole formula true. Solving Horn-satisfiability problems is the central computational paradigm in the Prolog programming language.
Gallier is also the author of five books in computational logic,
computational geometry,
low-dimensional topology,
and discrete mathematics.
Selected publications
Research papers
Books
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https://en.wikipedia.org/wiki/Free%20flight%20%28model%20aircraft%29
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Free flight is the segment of model aviation involving aircraft with no active external control after launch. Free Flight is the original form of hobby aeromodeling, with the competitive objective being to build and launch a self controlling aircraft that will consistently achieve the longest flight duration over multiple competition rounds, within various class parameters.
Description
The essence of free-flight is that the aircraft have no need for external control, for instance by radio. Aircraft of this type have been flown for over two centuries. They are designed to be inherently stable in flight; if disturbed by a gust of wind or a thermal current they will return automatically to stable flight. Their stability is achieved by a combination of design and trim, - the relationship between centre of gravity, wing and tailplane incidence and rudder setting.
With their much lower wing loading, free-flight aircraft fly much more slowly than the engine-powered radio-controlled aircraft that many people first think of when ‘model aircraft’ is mentioned. Most of them glide at little more than walking pace and few weigh more than 500 grams.
Usually the sole objective of free-flight competition is flight duration, and one of the sport’s fascinations and challenges is to design the most efficient aircraft within the various competition limits on parameters such as minimum weight, maximum wing area, and motive power.
Types
Free flight models may be broadly divided into four categories:
Gliders (towline and hand-launched)
Rubber-powered (pure duration, and scale with duration)
Power (CO2, methanol-fueled glow engine, or electric)
Indoor (pure duration, and scale with duration)
When flown competitively, the usual aim is maximum flight duration. In the case of models flown outdoors, the modeler attempts to launch the model into arising column of air, a thermal. These outdoor free flight models tend to be designed for two very different flying modes: climbing ra
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https://en.wikipedia.org/wiki/Subclavius%20muscle
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The subclavius is a small triangular muscle, placed between the clavicle and the first rib. Along with the pectoralis major and pectoralis minor muscles, the subclavius muscle makes up the anterior axioappendicular muscles, also known as anterior wall of the axilla.
Structure
It arises by a short, thick tendon from the first rib and its cartilage at their junction, in front of the costoclavicular ligament.
The fleshy fibers proceed obliquely superolaterally, to be inserted into the groove on the under surface of the clavicle.
Innervation
The nerve to subclavius (or subclavian nerve) innervates the muscle. This arises from the junction of the fifth and sixth cervical nerves, from the superior/upper trunk of the brachial plexus.
Variation
Insertion into coracoid process instead of clavicle or into both clavicle and coracoid process. Sternoscapular fasciculus to the upper border of scapula. Sternoclavicularis from manubrium to clavicle between pectoralis major and coracoclavicular fascia. Rarely, the subclavius may be missing entirely.
Function
It depresses the lateral clavicle, acts to stabilize the clavicle while the shoulder moves the arm. It also raises the first rib while lowering the clavicle during breathing.
The subclavius protects the underlying brachial plexus and subclavian vessels from a broken clavicle - the most frequently broken long bone.
Additional images
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https://en.wikipedia.org/wiki/Non-standard%20model%20of%20arithmetic
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In mathematical logic, a non-standard model of arithmetic is a model of first-order Peano arithmetic that contains non-standard numbers. The term standard model of arithmetic refers to the standard natural numbers 0, 1, 2, …. The elements of any model of Peano arithmetic are linearly ordered and possess an initial segment isomorphic to the standard natural numbers. A non-standard model is one that has additional elements outside this initial segment. The construction of such models is due to Thoralf Skolem (1934).
Non-standard models of arithmetic exist only for the first-order formulation of the Peano axioms; for the original second-order formulation, there is, up to isomorphism, only one model: the natural numbers themselves.
Existence
There are several methods that can be used to prove the existence of non-standard models of arithmetic.
From the compactness theorem
The existence of non-standard models of arithmetic can be demonstrated by an application of the compactness theorem. To do this, a set of axioms P* is defined in a language including the language of Peano arithmetic together with a new constant symbol x. The axioms consist of the axioms of Peano arithmetic P together with another infinite set of axioms: for each numeral n, the axiom x > n is included. Any finite subset of these axioms is satisfied by a model that is the standard model of arithmetic plus the constant x interpreted as some number larger than any numeral mentioned in the finite subset of P*. Thus by the compactness theorem there is a model satisfying all the axioms P*. Since any model of P* is a model of P (since a model of a set of axioms is obviously also a model of any subset of that set of axioms), we have that our extended model is also a model of the Peano axioms. The element of this model corresponding to x cannot be a standard number, because as indicated it is larger than any standard number.
Using more complex methods, it is possible to build non-standard models that
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https://en.wikipedia.org/wiki/Walter%20Dubislav
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Walter Dubislav (20 September 1895 – 17 September 1937) was a German logician and philosopher of science (Wissenschaftstheoretiker).
Biography
After studying mathematics and philosophy, Dubislav attained a doctorate in 1922 with "Contributions to the theories of definition and proof within mathematical logic" (Beiträge zur Lehre von der Definition und vom Beweis vom Standpunkt der mathematischen Logik aus). In 1928 he became a private lecturer in philosophy of mathematics and the natural sciences at the Technical University of Berlin and from 1931 was Professor Extraordinarius (außerordentlicher Professor, ao. Prof.). In 1936 he emigrated to Prague.
He was joint founder (with Hans Reichenbach and Kurt Grelling) of the 'Berlin Society for Empirical (later: Scientific) Philosophy' (Berliner Gesellschaft für empirische Philosophie), which, along with the Vienna Circle, is one of the points of origin of logical empiricism. The founding members of the Berlin Circle were listed as sympathisers within the Vienna Circle.
Dubislav focused on a logical and mechanistic foundation of mathematics and physics, influenced by Bernard Bolzano's "Theory of Science" (Wissenschaftslehre). He presented a formalised account of Gottlob Frege's theory of definitions.
Publications
With Claubberg, K.W.: "A Systematic Dictionary of Philosophy" (Systematisches Wörterbuch der Philosophie). Felix Meiner, Leipzig 1923.
"On Definitions" (Über die Definition). Weiss, Berlin 1926; 2nd edition published 1927; "Definition" (Die Definition), revised and augmented 3rd edition, Felix Meiner, Leipzig 1931; 4th edition, with an introduction by Wilhelm K. Essler, published by Meiner, Hamburg 1981 .
"On the so-called analytic and synthetic judgements" (Über die sogennanten analytischen und synthetischen Urteile). Weiss, Berlin 1926.
"Fries' Theory of Meaning" (Die Friessche Lehre von der Begründung) in "Representation and Criticism" (Darstellung und Kritik), E. Mattig, Dömitz 1926.
"On the Theory of
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https://en.wikipedia.org/wiki/Popeye%20protein%20conserved%20region
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Popeye protein conserved region is common to a family of evolutionarily related proteins, the Popeye domain containing (POPDC) family of proteins, which is found in many animal phyla (vertebrates, lower chordates, arthropodes, mollusca and some protostomia).
In vertebrates it is preferentially expressed in developing and adult striated muscle (heart and skeletal muscle). It is represented by a conserved region, the Popeye domain, which functions as a cAMP-binding domain. All POPDC proteins also have three potential transmembrane domains. The strong conservation of POPDC genes during evolution and their preferential expression in heart and skeletal muscle suggest that these proteins may have an important function in these tissues in vertebrates.
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https://en.wikipedia.org/wiki/Multidimensional%20signal%20restoration
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In multidimensional signal processing, Multidimensional signal restoration refers to the problem of estimating the original input signal from observations of the distorted or noise contaminated version of the original signal using some prior information about the input signal and /or the distortion process. Multidimensional signal processing systems such as audio, image and video processing systems often receive as input, signals that undergo distortions like blurring, band-limiting etc. during signal acquisition or transmission and it may be vital to recover the original signal for further filtering. Multidimensional signal restoration is an inverse problem, where only the distorted signal is observed and some information about the distortion process and/or input signal properties is known. A general class of iterative methods have been developed for the multidimensional restoration problem with successful applications to multidimensional deconvolution, signal extrapolation and denoising.
Definition
In general, the multidimensional signal restoration problem can be represented by an equation of the form,
where represents the observed m-dimensional distorted output signal, represents the m-dimensional undistorted input signal and represents the distortion operator acting upon the input signal. can be used to model a wide range of transformations such as blurring, additive noise, time limiting, band limiting etc. of multidimensional signals.
A simple straightforward solution to above equation is of the form,
where is the inverse distortion operator.
However, in most cases of practical use, it may be extremely difficult to implement the inverse distortion operator or the such an inverse distortion operator may not exist and even in situations where the distortion operator is known and its inverse can be approximately implemented, the resultant reconstructed signal can have very large reconstruction errors due to the inaccuracies present in the estimation
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https://en.wikipedia.org/wiki/Future%20Knight
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Future Knight is a 2D, flip screen platform game released by Gremlin Graphics in 1986 for the Amstrad CPC, Commodore 64, MSX, and ZX Spectrum. The player must guide Randolph through twenty levels of hostile robots and aliens before defeating Spegbott and rescuing Amelia.
Plot
The space cruiser S.S. Rustbucket has crashed on Planet 2749 of the Zragg System, and its passengers been taken hostage by Spegbott the Terrible and his minions. Among them is the Princess Amelia, beloved of the Future Knight Randolph, who has now teleported into the wreck of the Rustbucket to defeat Spegbott and rescue her.
Gameplay
An undocumented level editor is included in the Spectrum version which can be accessed from the main menu by pressing the key combination EDIT-F-K.
Reception
Sinclair User:
The game was reviewed in 1990 in Dragon #158 by Hartley, Patricia, and Kirk Lesser in "The Role of Computers" column, as part of the Mastertronic MEGA Pack of 10 games previously released in Europe. The reviewers gave the game 1 out of 5 stars, stating "You’re inside a spaceship trying to find a princess in distress; a really dumb game".
Reviews
Jeux & Stratégie #43
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https://en.wikipedia.org/wiki/Permease%20of%20phosphotransferase%20system
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Permease of phosphotransferase system (or PTS-AG superfamily according to TCDB) is a superfamily of phosphotransferase enzymes that facilitate the transport of L-ascorbate (A) and galactitol (G). Classification has been established through phylogenic analysis and bioinformatics.
The bacterial phosphoenolpyruvate:sugar phosphotransferase system (PTS) transports and phosphorylates its sugar substrates in a single energy-coupled step. This transport process is dependent on several cytoplasmic phosphoryl transfer proteins - Enzyme I (I), HPr, Enzyme IIA (IIA), and Enzyme IIB (IIB)) as well as the integral membrane sugar permease (IIC). The PTS Enzyme II complexes are derived from independently evolving 4 PTS Enzyme II complex superfamilies, that include the (1) Glucose (Glc),(2) Mannose (Man), (3) Ascorbate-Galactitol (Asc-Gat) and (4) Dihydroxyacetone (Dha) superfamilies.
The four families that make up the PTS-GFL superfamily include:
4.A.5 – The PTS Galactitol (Glc) Family
4.A.7 – The PTS L-Ascorbate (L-Asc) Family
See also
Phosphotransferases system
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https://en.wikipedia.org/wiki/Evolvability%20%28computer%20science%29
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The term evolvability is used for a recent framework of computational learning introduced by Leslie Valiant in his paper of the same name and described below. The aim of this theory is to model biological evolution and categorize which types of mechanisms are evolvable. Evolution is an extension of PAC learning and learning from statistical queries.
General framework
Let and be collections of functions on variables. Given an ideal function , the goal is to find by local search a representation that closely approximates . This closeness is measured by the performance of with respect to .
As is the case in the biological world, there is a difference between genotype and phenotype. In general, there can be multiple representations (genotypes) that correspond to the same function (phenotype). That is, for some , with , still for all . However, this need not be the case. The goal then, is to find a representation that closely matches the phenotype of the ideal function, and the spirit of the local search is to allow only small changes in the genotype. Let the neighborhood of a representation be the set of possible mutations of .
For simplicity, consider Boolean functions on , and let be a probability distribution on . Define the performance in terms of this. Specifically,
Note that In general, for non-Boolean functions, the performance will not correspond directly to the probability that the functions agree, although it will have some relationship.
Throughout an organism's life, it will only experience a limited number of environments, so its performance cannot be determined exactly. The empirical performance is defined by
where is a multiset of independent selections from according to . If is large enough, evidently will be close to the actual performance .
Given an ideal function , initial representation , sample size , and tolerance , the mutator is a random variable defined as follows. Each is classified as beneficial, neutral, or deleteriou
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https://en.wikipedia.org/wiki/Dispersal%20of%20invasive%20species%20by%20ballast%20water
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The dispersal of invasive species by ballast water refers to the unintentional introduction of invasive species to new habitats via the ballast water carried by commercial shipping vessels. Ballast water spreads an estimated 7000 living species to new habitats across the globe. These species can affect the ecological balance of their new regions by outcompeting native species or otherwise impacting native ecosystems.
Ballast water
The purpose of ballast water is to provide transverse stability, improve propulsion and maneuverability, and to compensate for weight loss due to fuel and water consumption. Approximately 10 billion tons of ballast water is transported each year, accounting for 90% of our world trade. Typically, ballast water discharge contains a variety of biological materials including non-native, invasive, and exotic species that can cause extensive ecological and economic damage to aquatic ecosystems.
Throughout this process, large ships withdraw up to 20 million gallons of water at their specific loading ports. Including native species; both plant and animal, before disposing them at their next destination. However, when these invasive species are unloaded, specific conditions like temperature, salinity, lack of resources, and predator-to-prey competition affects how foreign species survive in non-native habitats. These factors cause stress within the ecosystems, throwing off ecological and environmental balance.
As new species are introduced to non-native ecosystems, interspecific competition often becomes more intense. If native species are outcompeted by invasive species, it can affect the established predator-prey relationships within that region, possibly having disruptive effects on the wider food web.
Invasive species
Freshwater zebra mussel
Dreissena polymorpha, commonly known as the zebra mussel, live in freshwater and are native to southern lakes in Russia and Ukraine. The zebra mussel has become an invasive species that is frequen
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https://en.wikipedia.org/wiki/Ittiam%20Systems
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Ittiam Systems is a venture capital funded technology company founded by ex-Managing Director of Texas Instruments' India Srini Rajam in 2001. It is headquartered in Bangalore, India and has marketing offices in the United States, UK, France, Japan, Mainland China, Singapore and Taiwan.
Ittiam Systems is India's first technology firm to be based on licensing of intellectual property (IP). Revenue is mainly generated through licensing of its DSP intellectual property and reference designs.
One of its early United States customers was e.Digital Corporation, a San Diego-based company that developed the digEplayer portable audio/video in-flight entertainment device under contract by Tacoma, Washington-based APS, now named digEcor.
Ittiam Systems demonstrated its HEVC and VP9 implementations accelerated using ARM Mali-T600 GPU Compute technology at CES 2014 and MWC 2014.
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https://en.wikipedia.org/wiki/Bioconvergence
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Bioconvergence is a multidisciplinary method in life science. It uses the synergy between biotech, engineering and computerized systems to address unresolved challenges, like speeding up diagnostic processes, creating more advanced materials, or advancing drug development.
Along with healthcare, bioconvergence assists in the improvement of various sectors such as agriculture, energy, food, security, climate, etc. McKinsey research predicts that more than half of the impact of bioconvergence will be outside of healthcare, in areas such as agriculture, aquaculture and food, consumer products and services (such as DNA and microbiome testing), novel materials, chemistry and energy. According to McKinsey, bioconvergence solutions currently being developed could have an economic impact of up to per year over the next 10 to 20 years.
Implications
Bioconvergence uses methods from disciplines such as biology, chemistry, physics, engineering, medicine, mathematics, agriculture, computational sciences and artificial intelligence (AI), in order to solve challenges across several sectors.
Healthcare
Bioconvergence technologies in healthcare include translational medicine, enabling the extraction of hidden insights from massive data sets; neuromorphic computing, who seeks to emulate the biological neural structure of the brain to achieve unparalleled levels of processing performance and energy efficiency; creation of digital twins for clinical trials; and biochips such as organ on a chip" (OOC). Other implications of bioconvergence include new methods ot using nanorobotics for drug delivery, regenerative medicine, diagnostics and biological sensors, optogenetics, bioelectronics, engineered "living" materials, and more. According to Belén Garijo, CEO of Merck, bioconvergence can also bring about the potential of personalized medicine".
Food and agriculture
Traditional agriculture relies on land, water, and a suitable climate. In the future, based on bioconvergence led resea
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https://en.wikipedia.org/wiki/H%20square
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In mathematics and control theory, H2, or H-square is a Hardy space with square norm. It is a subspace of L2 space, and is thus a Hilbert space. In particular, it is a reproducing kernel Hilbert space.
On the unit circle
In general, elements of L2 on the unit circle are given by
whereas elements of H2 are given by
The projection from L2 to H2 (by setting an = 0 when n < 0) is orthogonal.
On the half-plane
The Laplace transform given by
can be understood as a linear operator
where is the set of square-integrable functions on the positive real number line, and is the right half of the complex plane. It is more; it is an isomorphism, in that it is invertible, and it isometric, in that it satisfies
The Laplace transform is "half" of a Fourier transform; from the decomposition
one then obtains an orthogonal decomposition of into two Hardy spaces
This is essentially the Paley-Wiener theorem.
See also
H∞
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https://en.wikipedia.org/wiki/Sequent
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In mathematical logic, a sequent is a very general kind of conditional assertion.
A sequent may have any number m of condition formulas Ai (called "antecedents") and any number n of asserted formulas Bj (called "succedents" or "consequents"). A sequent is understood to mean that if all of the antecedent conditions are true, then at least one of the consequent formulas is true. This style of conditional assertion is almost always associated with the conceptual framework of sequent calculus.
Introduction
The form and semantics of sequents
Sequents are best understood in the context of the following three kinds of logical judgments:
<li>Unconditional assertion. No antecedent formulas.
Example: ⊢ B
Meaning: B is true.
<li>Conditional assertion. Any number of antecedent formulas.
<li>Simple conditional assertion. Single consequent formula.
Example: A1, A2, A3 ⊢ B
Meaning: IF A1 AND A2 AND A3 are true, THEN B is true.
<li>Sequent. Any number of consequent formulas.
Example: A1, A2, A3 ⊢ B1, B2, B3, B4
Meaning: IF A1 AND A2 AND A3 are true, THEN B1 OR B2 OR B3 OR B4 is true.
Thus sequents are a generalization of simple conditional assertions, which are a generalization of unconditional assertions.
The word "OR" here is the inclusive OR. The motivation for disjunctive semantics on the right side of a sequent comes from three main benefits.
The symmetry of the classical inference rules for sequents with such semantics.
The ease and simplicity of converting such classical rules to intuitionistic rules.
The ability to prove completeness for predicate calculus when it is expressed in this way.
All three of these benefits were identified in the founding paper by .
Not all authors have adhered to Gentzen's original meaning for the word "sequent". For example, used the word "sequent" strictly for simple conditional assertions with one and only one consequent formula. The same single-consequent definition for a sequent is given by .
Syntax details
In a gene
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https://en.wikipedia.org/wiki/Periodic%20short-interval%20diffuse%20discharges
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Periodic short-interval diffuse discharges are a type of EEG abnormality with periodicity less than 4.0 seconds. They can consist of sharp waves or spikes, spike and wave, polyspikes or triphasics with background attenuation in between transients.
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https://en.wikipedia.org/wiki/Precancerous%20condition
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A precancerous condition is a condition, tumor or lesion involving abnormal cells which are associated with an increased risk of developing into cancer. Clinically, precancerous conditions encompass a variety of abnormal tissues with an increased risk of developing into cancer. Some of the most common precancerous conditions include certain colon polyps, which can progress into colon cancer, monoclonal gammopathy of undetermined significance, which can progress into multiple myeloma or myelodysplastic syndrome. and cervical dysplasia, which can progress into cervical cancer. Bronchial premalignant lesions can progress to squamous cell carcinoma of the lung.
Pathologically, precancerous tissue can range from benign neoplasias, which are tumors which don't invade neighboring normal tissues or spread to distant organs, to dysplasia, a collection of highly abnormal cells which, in some cases, has an increased risk of progressing to anaplasia and invasive cancer which is life-threatening. Sometimes, the term "precancer" is also used for carcinoma in situ, which is a noninvasive cancer that has not grown and spread to nearby tissue, unlike the invasive stage. As with other precancerous conditions, not all carcinoma in situ will become an invasive disease but is at risk of doing so.
Classification
The term precancerous or premalignant condition may refer to certain conditions, such as monoclonal gammopathy of unknown significance, or to certain lesions, such as colorectal adenoma (colon polyps), which have the potential to progress into cancer (see: Malignant transformation). Premalignant lesions are morphologically atypical tissue which appear abnormal when viewed under the microscope, and which are more likely to progress to cancer than normal tissue. Precancerous conditions and lesions affect a variety of organ systems, including the skin, oral cavity, stomach, colon, lung, and hematological system. Some authorities also refer to hereditary genetic conditions which p
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https://en.wikipedia.org/wiki/Macadamia%20oil
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Macadamia oil (or macadamia nut oil) is the non-volatile oil collected from the nuts of the macadamia (Macadamia integrifolia), a native Australian plant. It is used in food as a frying or salad oil, and in cosmetic formulations as an emollient or fragrance fixative.
Description
Fruits
Macadamia integrifolia is an Australian tree with holly-like leaves that grows well in a moist organic soil and can withstand temperatures as low as −4.4 °C (24 °F). Seedlings bear in 5–7 years. The fruit is borne in a case enclosing an extremely hard spherical nut. The kernel is whitish, sweet and eaten raw or roasted. The flowers are white to cream and the leaves are in whorls of three. Propagation is by seed, grafting or air layering. It is grown commercially.
Common names of the trees are the Australian nut or the Queensland nut. Species that are “smooth shelled macadamia” are called Macadamia integrifolia and “rough shelled macadamia” are called Macadamia tetraphylla. Macadamia ternifolia is also the name used for M. integrifolia. Macadamia integrifolia is native to Australia where it grows in rain forests and close to streams. Macadamia tetraphylla is native to Southeastern Queensland and Northeastern New South Wales.
Oil
The oil content ranges from 65% to 75% and sugar content ranges from 6% to 8%. These factors result in variable colors and texture when the nuts are roasted under the same conditions.
Macadamia oil is liquid at room temperature. The refined oil is clear, lightly amber-colored with a slightly nutty smell. It has a specific gravity of 900–920 and a flash point of over 300 °C (572 °F).
Oil accumulation does not commence until the nuts are fully grown and the shell hardens. It accumulates rapidly in the kernel during late summer when the reducing sugar content decreases. The composition of mature, roasted and salted macadamia nuts is shown. As with many oil seeds, the protein is low in methionine. Fresh kernels contain up to 4.6% sugar, mostly non-reducing
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https://en.wikipedia.org/wiki/Body%20of%20penis
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The body or shaft of the penis is the free portion of the human penis that is located outside of the pelvic cavity. It is the continuation of the internal root which is embedded in the pelvis and extends to the glans behind which lies the neck of the penis. It is made up of the two corpora cavernosa and the corpus spongiosum on the underside. The corpora cavernosa are intimately bound to one another with a dorsally fenestrated septum which becomes a complete one before the penile crura. The body of the penis is homologous to the female clitoral body.
Anatomy
The body of the penis is suspended from the pubic symphysis. It has two surfaces; the dorsal and the ventral or urethral. The penile raphe runs on its ventral surface.
The body is surrounded by a bi-layered model of tunica albuginea in which a distal ligament buttresses the glans penis and plays an integral role to the penile fibroskeleton, and the structure is called "os analog", a term coined by Geng Long Hsu in the Encyclopedia of Reproduction. This indispensable structure is a continuation of the body of the human penis, differing from other mammalian penises, in that it has no baculum (or erectile bone) and instead relies exclusively on engorgement with blood to reach its erect state. It is a remnant of baculum evolved likely due to change in mating practice.
A shallow groove which marks their junction on the upper surface lodges the deep dorsal vein of the penis which is flanked by a pair of cavernosal veins of the penis, while a deeper and wider groove between them on the surface below contains the corpus spongiosum. The body is ensheathed by fascia which includes tunica albuginea, Buck's fascia, dermis, and skin.
See also
Root of penis
Additional Images
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https://en.wikipedia.org/wiki/Roll%27s%20critique
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Roll's critique is a famous analysis of the validity of empirical tests of the capital asset pricing model (CAPM) by Richard Roll. It concerns methods to formally test the statement of the CAPM, the equation
This equation relates an asset's expected return to the asset's sensitivity to the market portfolio return . The market return is defined as the wealth-weighted sum of all investment returns in the economy.
Roll's critique makes two statements regarding the market portfolio:
1. Mean-variance tautology: Any mean-variance efficient portfolio satisfies the CAPM equation exactly:
.
(A portfolio is mean-variance efficient if there is no portfolio that has a higher return and lower risk than those for the efficient portfolio.) Mean-variance efficiency of the market portfolio is equivalent to the CAPM equation holding. This statement is a mathematical fact, requiring no model assumptions.
Given a proxy for the market portfolio, testing the CAPM equation is equivalent to testing mean-variance efficiency of the portfolio. The CAPM is tautological if the market is assumed to be mean-variance efficient.
2. The market portfolio is unobservable: The market portfolio in practice would necessarily include every single possible available asset, including real estate, precious metals, stamp collections, jewelry, and anything with any worth.
The returns on all possible investments opportunities are unobservable.
From statement 1, validity of the CAPM is equivalent to the market being mean-variance efficient with respect to all investment opportunities. Without observing all investment opportunities, it is not possible to test whether this portfolio, or indeed any portfolio, is mean-variance efficient. Consequently, it is not possible to test the CAPM.
Relationship to the APT
The mean-variance tautology argument applies to the arbitrage pricing theory and all asset-pricing models of the form
where are unspecified factors. If the factors are returns on a mean-var
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https://en.wikipedia.org/wiki/William%20Fogg%20Osgood
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William Fogg Osgood (March 10, 1864 – July 22, 1943) was an American mathematician.
Education and career
William Fogg Osgood was born in Boston on March 10, 1864. In 1886, he graduated from Harvard, where, after studying at the universities of Göttingen (1887–1889) and Erlangen (Ph.D., 1890), he was instructor (1890–1893), assistant professor (1893–1903), and thenceforth professor of mathematics. From 1918 to 1922, he was chairman of the department of mathematics at Harvard. He became professor emeritus in 1933. From 1934 to 1936, he was visiting professor of mathematics at Peking University.
From 1899 to 1902, he served as editor of the Annals of Mathematics, and in 1905–1906 was president of the American Mathematical Society, whose Transactions he edited in 1909–1910.
Contributions
The works of Osgood dealt with complex analysis, in particular conformal mapping and uniformization of analytic functions, and calculus of variations. He was invited by Felix Klein to write an article on complex analysis in the Enzyklopädie der mathematischen Wissenschaften which was later expanded in the book Lehrbuch der Funktionentheorie.
Osgood curves – Jordan curves with positive area – are named after Osgood, who published a paper proving their existence in 1903.
Besides his research on analysis, Osgood was also interested in mathematical physics and wrote on the theory of the gyroscope.
Awards and honors
In 1904, he was elected to the National Academy of Sciences.
Personal life
Osgood's cousin, Louise Osgood, was the mother of Bernard Koopman.
William Fogg Osgood died at his home in Belmont, Massachusetts on July 22, 1943.
Selected publications
Osgood's books include:
Introduction to Infinite Series (Harvard University Press 1897; third edition, 1906)
Lehrbuch der Funktionentheorie (Teubner, Berlin, 1907; second edition, 1912)
First Course in Differential and Integral Calculus (1907; revised edition, 1909)
(with W. C. Graustein) Plane and Solid Analytic Geometry
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https://en.wikipedia.org/wiki/Plastic%20pollution%20in%20the%20Mediterranean%20sea
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The Mediterranean Sea has been defined as one of the seas most affected by marine plastic pollution.
It has concentrations of microplastics which are estimated to be higher than those on average found at the global level. Studies conducted within the WWF Mediterranean Marine Initiative of 2019 have estimated that 0.57 million metric tons of plastic enter the Mediterranean Sea every year; this quantity corresponds to the dumping of 33.800 bottles made of plastic into waters every minute, representing important risks for marine ecosystems, human health, but also for the blue economy of the area, whose coastal zones are very densely populated and among the first tourist destinations worldwide.
Marine plastic pollution was found in Mediterranean waters in amounts similar to those present in the ocean gyres (Indian Ocean Gyre, North Atlantic Gyre, North Pacific Gyre, South Atlantic Gyre, South Pacific Gyre). Therefore, the Mediterranean Sea is oftentimes being defined as the "world's sixth greatest accumulation zone" for marine plastic litter or as an invisible "sixth garbage patch", primarily composed of microplastics. This is an invisible garbage patch as there is no trace of permanent litter accumulation areas in the Mediterranean Sea, primarily because of the semi-enclosed shape of its basin, the cyclonic circulation and the currents present in the region.
The Mediterranean Sea receives waste from coastal areas and from waters, such as rivers (like in the case of the Nile river, which, as of 2017, brought around 200 tonnes of plastic waste into the Mediterranean basin yearly).
A World Wide Fund for Nature report of 2019 estimates that, considering the Mediterranean countries, around 70% of plastic pollution coming from water-based sources comes from three areas: Egypt (41.3%), Turkey (19.1%) and Italy (7.6%). Plastic litter originating from land-based sources is instead estimated to be coming from, in decreasing order: Turkey, Morocco, Israel, Spain, France, Syria
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https://en.wikipedia.org/wiki/Left%20axis%20deviation
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In electrocardiography, left axis deviation (LAD) is a condition wherein the mean electrical axis of ventricular contraction of the heart lies in a frontal plane direction between −30° and −90°. This is reflected by a QRS complex positive in lead I and negative in leads aVF and II.
There are several potential causes of LAD. Some of the causes include normal variation, thickened left ventricle, conduction defects, inferior wall myocardial infarction, pre-excitation syndrome, ventricular ectopic rhythms, congenital heart disease, high potassium levels, emphysema, mechanical shift, and paced rhythm.
Symptoms and treatment of left axis deviation depend on the underlying cause.
Defining left axis deviation
Cardiac axis in electrocardiography represents the sum of depolarization vectors generated by individual cardiac myocytes. To interpret the cardiac axis, one has to determine the relationship between the QRS axis and limb leads of the ECG. Usually, left ventricles makes up most of the heart muscles, so a normal cardiac axis is directed downward and slightly to the left. In a normal axis, QRS is between -30° and +90°. In contrast to that, left axis deviation (LAD) is defined as QRS axis between −30° and −90°, and right axis deviation is defined as QRS axis greater than +90°, while extreme axis deviation occurs when QRS axis is between -90° and 180°.
Determining left axis deviation
Determining the electrical axis can provide insight into underlying disease states and help steer the differential diagnosis. There are several methods to determining the ECG axis. The easiest method is the quadrant method, where one looks at lead I and lead aVF. First, examine the QRS complex in both leads I and avF and determine if the QRS complex is positive (height of R wave > S wave), equiphasic (R wave = S wave), or negative (R wave < S wave). If lead I is positive and lead aVF is negative, then this is a possible LAD. To determine a true LAD, examine QRS in lead II. If the QRS com
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https://en.wikipedia.org/wiki/Bailey%E2%80%93Borwein%E2%80%93Plouffe%20formula
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The Bailey–Borwein–Plouffe formula (BBP formula) is a formula for . It was discovered in 1995 by Simon Plouffe and is named after the authors of the article in which it was published, David H. Bailey, Peter Borwein, and Plouffe. Before that, it had been published by Plouffe on his own site. The formula is
The BBP formula gives rise to a spigot algorithm for computing the nth base-16 (hexadecimal) digit of (and therefore also the 4nth binary digit of ) without computing the preceding digits. This does not compute the nth decimal of (i.e., in base 10). But another formula discovered by Plouffe in 2022 allows extracting the nth digit of in decimal. BBP and BBP-inspired algorithms have been used in projects such as PiHex for calculating many digits of using distributed computing. The existence of this formula came as a surprise. It had been widely believed that computing the nth digit of is just as hard as computing the first n digits.
Since its discovery, formulas of the general form
have been discovered for many other irrational numbers , where and are polynomials with integer coefficients and is an integer base.
Formulas of this form are known as BBP-type formulas. Given a number , there is no known systematic algorithm for finding appropriate , , and ; such formulas are discovered experimentally.
Specializations
A specialization of the general formula that has produced many results is
where s, b, and m are integers, and is a sequence of integers.
The P function leads to a compact notation for some solutions. For example, the original BBP formula
can be written as
Previously known BBP-type formulae
Some of the simplest formulae of this type that were well known before BBP and for which the P function leads to a compact notation, are:
(In fact, this identity holds true for a > 1:
.)
Plouffe was also inspired by the arctan power series of the form (the P notation can be also generalized to the case where b is not an integer):
The search for
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https://en.wikipedia.org/wiki/Kama%20%28food%29
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Kama (in Estonian) or talkkuna (in Finnish) or tolokno (in Russian: толокно), talqan (in Turkic languages) is a traditional Estonian, Finnish, Russian, Turkic finely milled flour mixture. The kama or talkkuna powder is a mixture of roasted barley, rye, oat and pea flour. The oat flour may be completely replaced by wheat flour, or kibbled black beans may be added to the mixture. In Finland talkkuna is made by first steaming grains, then grinding them up and finally roasting them into talkkuna.
"Historically kama was a non-perishable, easy-to-carry food that could be quickly fashioned into a stomach-filling snack by rolling it into butter or lard; it did not require baking, as it was already roasted".
Nowadays it is used for making some desserts. It is mostly enjoyed for breakfast mixed with milk, buttermilk or kefir as mush. It is frequently sweetened with sugar and especially with blueberry, more rarely with other fruits or honey or served unsweetened. It is also used for milk or sour desserts, together with the forest berries typical in Estonia and Finland.
Kama can be bought as a souvenir in Estonia, where it is a distinctive national food.
A similar product is skrädmjöl, a flour consisting exclusively of roasted oats which is traditionally made in the Swedish province of Värmland. It was brought there by Forest Finns.
In Turkic languages, it is called talqan. It is made of coarse or finely milled flour from roasted barley or wheat. It is common in the cuisine of Altay people, Nogays, Bashkirs, Kazakhs, Tatars, Tuvans, Uzbeks, Khakas.
See also
Gofio
Misutgaru
Rubaboo
Tsampa
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https://en.wikipedia.org/wiki/Global%20Biodiversity%20Information%20Facility
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The Global Biodiversity Information Facility (GBIF) is an international organisation that focuses on making scientific data on biodiversity available via the Internet using web services. The data are provided by many institutions from around the world; GBIF's information architecture makes these data accessible and searchable through a single portal. Data available through the GBIF portal are primarily distribution data on plants, animals, fungi, and microbes for the world, and scientific names data.
The mission of the GBIF is to facilitate free and open access to biodiversity data worldwide to underpin sustainable development. Priorities, with an emphasis on promoting participation and working through partners, include mobilising biodiversity data, developing protocols and standards to ensure scientific integrity and interoperability, building an informatics architecture to allow the interlinking of diverse data types from disparate sources, promoting capacity building and catalysing development of analytical tools for improved decision-making.
GBIF strives to form informatics linkages among digital data resources from across the spectrum of biological organisation, from genes to ecosystems, and to connect these to issues important to science, society and sustainability by using georeferencing and GIS tools. It works in partnership with other international organisations such as the Catalogue of Life partnership, Biodiversity Information Standards, the Consortium for the Barcode of Life (CBOL), the Encyclopedia of Life (EOL), and GEOSS. The biodiversity data available through the GBIF has increased by more than 1,150% in the past decade, partially due to the participation of citizen scientists.
From 2002 to 2014, GBIF awarded a prestigious annual global award in the area of biodiversity informatics, the Ebbe Nielsen Prize, valued at €30,000. , the GBIF Secretariat presents two annual prizes: the GBIF Ebbe Nielsen Challenge and the Young Researchers Award.
See al
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https://en.wikipedia.org/wiki/Buchanan%20Medal
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The Buchanan Medal is awarded by the Royal Society "in recognition of distinguished contribution to the medical sciences generally". The award was created in 1897 from a fund to the memory of London physician Sir George Buchanan (1831–1895). It was to be awarded once every five years, but since 1990 the medal has been awarded every two years.
Since its creation, it has been awarded 28 times, and unlike other Royal Society medals such as the Royal Medal, it has never been awarded to the same individual multiple times. As a result of the criteria for the medal, most of the winners have been doctors or other medical professionals; an exception was Frederick Warner, an engineer who won the medal in 1982 "for his important role in reducing pollution of the River Thames and of his significant contributions to risk assessment".
Two winners have also won a Nobel Prize. The first, Barry Marshall, who was awarded the Buchanan Medal in 1998 "in recognition of his work on discovering the role of Helicobacter pylori as a cause of diseases such as duodenal ulcer, gastric ulcer, gastric cancer and gastritis-associated dyspepsia" and won the Nobel Prize in Physiology or Medicine in 2005. The second, Peter Ratcliffe, won the medal in 2017 "for his ground-breaking research on oxygen sensing and signalling pathways mediating cellular responses to hypoxia", and was awarded the Nobel Prize in 2019.
The first winner of the Buchanan Medal was John Simon, who won his medal in 1897 "for his distinguished services as an organizer of medical sanitary administration in this country, and as a promoter of scientific research relating to public health".
List of recipients
Source: Royal Society
See also
List of medicine awards
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https://en.wikipedia.org/wiki/Microsoft%20Forefront%20Unified%20Access%20Gateway
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Microsoft Forefront Unified Access Gateway (UAG) is a discontinued software suite that provides secure remote access to corporate networks for remote employees and business partners. Its services include reverse proxy, virtual private network (VPN), DirectAccess and Remote Desktop Services. UAG was released in 2010, and is the successor for Microsoft Intelligent Application Gateway (IAG) which was released in 2007. UAG is part of the Microsoft Forefront offering. Microsoft discontinued the product in 2014, although the Web Application Proxy feature of Windows Server 2012 R2 and later offers some of its functionalities.
History
Unified Access Gateway was originally developed by a startup company named Whale Communications in Rosh HaAyin, Israel. Whale's initial product, e-Gap, was designed to create physical separation between networks of disparate trust levels. It consisted of an appliance housing a 512k memory chip that toggled connections between two servers via a SCSI bus. The product was originally built to offer sneaker-net services and shortly thereafter features to enable HTTP connections were added. In the 90's and early 2000's, e-Gap was enhanced to provide comprehensive reverse proxy features that included in-depth filtering of inbound traffic to ensure the security of the web servers and applications it protected. As adoption grew, the product pivoted to focus more specifically on Remote Access use-cases and additional features and licensing options were added to provide employee and contractor remote access across a range of connectivity options. In 2002, the market evolved into offering more comprehensive SSL VPN features. Whale's uniqueness was in its ability to granularly filter and alter the flow of traffic to enable a path of least access and protect from both known and unknown attacks/vulnerabilities using an application specific positive logic filtering engine.
On 18 May 2006, Microsoft announced that it would be acquiring Whale Communications
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https://en.wikipedia.org/wiki/American%20Society%20of%20Botanical%20Artists
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The American Society of Botanical Artists (ASBA) is the principal United States society for those who practice and appreciate contemporary botanical art. Since its founding by Diane Bouchier in 1994, ASBA has grown to nearly 2000 individual members in 39 countries and more than 40 institutional members from around the world.
ASBA members include botanical artists at all levels from beginners to masters, instructors, collectors, curators, botanical gardens, museums, academic institutions, and libraries.
Definition
The Society defines "botanical art" as
Having an aesthetic appeal, exhibiting the elements and principles of artistic design
Made to intent of elicit an intellectual or emotional response
To scale (actual size or scaled enlargement or reduction)
Free of animals except those that are interdependent with the plant and depicted subordinated to the plant
Free of backgrounds except for solid colors, textured substrates, or the natural habitat of the plant portrayed subordinate to the plant
Journals
ASBA publishes The Botanical Artist quarterly journal.
Exhibitions and awards
The ASBA organizes an Annual International Juried Exhibition in conjunction with the Horticultural Society of New York. At this annual exhibition, it awards the Diana Bouchier Artist Award for Excellence in Botanical Art, the James White Service Award for Dedication to Botanical Art, and the Botanical Illustrator Award for Excellence in Scientific Botanical Art.
2010 through 2014 - 13th, 14th, 15th, 16th, 17th International ASBA Botanical Art Exhibition at the Horticultural Society of New York
2015 through 2017 - 18th, 19th, 20th Annual International Exhibit at The New York Design Center
Fall 2018 - 21st Annual International Exhibit at Wave Hill
Fall 2019 - 22nd Annual International Exhibit at Marin Art & Garden Center, Ross, CA
Fall 2020 - 23rd Annual International Exhibit at Wave Hill
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https://en.wikipedia.org/wiki/MIPS-X
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MIPS-X is a reduced instruction set computer (RISC) microprocessor and instruction set architecture (ISA) developed as a follow-on project to the MIPS project at Stanford University by the same team that developed MIPS. The project, supported by the Defense Advanced Research Projects Agency (DARPA), began in 1984, and its final form was described in a set of papers released in 1986–87. Unlike its older cousin, MIPS-X was never commercialized as a workstation central processing unit (CPU), and has mainly been seen in embedded system designs based on chips designed by Integrated Information Technology (IIT) for use in digital video applications.
MIPS-X, while designed by the same team and architecturally very similar, is instruction-set incompatible with the mainline MIPS architecture R-series processors. The MIPS-X processor is obscure enough that, as of November 20, 2005, support for it is provided only by specialist developers (such as Green Hills Software), and is notably missing from the GNU Compiler Collection (GCC).
MIPS-X has become important among DVD player firmware hackers, since many DVD players (especially low-end devices) use chips based on the IIT design (and produced by ESS Technology), as their central processor. Devices such as the ESS VideoDrive system on a chip (SoC) also include a digital signal processor (DSP) (coprocessor) for decoding MPEG audio and video streams.
External links
The original MIPS-X paper from Stanford
Instruction set architectures
MIPS architecture
Stanford University
32-bit microprocessors
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https://en.wikipedia.org/wiki/Fixed-target%20experiment
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A fixed-target experiment in particle physics is an experiment in which a beam of accelerated particles is collided with a stationary target. The moving beam (also known as a projectile) consists of charged particles such as electrons or protons and is accelerated to relativistic speed. The fixed target can be a solid block or a liquid or a gaseous medium. These experiments are distinct from the collider-type experiments in which two moving particle beams are accelerated and collided. The famous Rutherford gold foil experiment, performed between 1908 and 1913, was one of the first fixed-target experiments, in which the alpha particles were targeted at a thin gold foil.
Explanation
The energy involved in a fixed target experiment is 4 times smaller compared to that in collider with the dual beams of same energy. More over in collider experiments energy of two beams is available to produce new particles, while in fixed target case a lot of energy is just expended in giving velocities to the newly created particles. This clearly implies that fixed target experiments are not helpful when it comes to increasing the energy scales of experiments. The targeted source also wears down with number of strikes and usually require a regular replacement. Current day fixed-target experiments try to use highly resistant materials but the damage cannot be avoided entirely.
The fixed target experiments have a significant advantage for experiments that require higher luminosity (rate of interaction). The High Luminosity Large Hadron Collider, which is an upcoming upgraded version of the Large Hadron Collider (LHC) at CERN, will attain total integrated luminosity of around in its run. While luminosity scale of about have already been approached by older fixed target experiments such at the E288 lead by Leon Lederman at Fermilab. Another advantage for fixed-target experiments is that they are easier and cheaper to build compared to the collider accelerators.
Experimental facilities
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https://en.wikipedia.org/wiki/Cellular%20adaptation
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In cell biology and pathophysiology, cellular adaptation refers to changes made by a cell in response to adverse or varying environmental changes. The adaptation may be physiologic (normal) or pathologic (abnormal).
Morphological adaptations observed at the cellular level include atrophy, hypertrophy, hyperplasia, and metaplasia. In the medical context, outside of specialized branches of biomedicine, morphological adaptations are not always referenced to the fundamental cellular level, but are observed and assessed at the level of tissues and organs. Dysplasia is a process of cell change associated with cellular abnormality, which is not considered adaptive in the positive sense of adaptation.
Atrophy
Cellular atrophy is a decrease in cell size. If enough cells in an organ undergo atrophy the entire organ will decrease in size. Thymus atrophy during early human development (childhood) is an example of physiologic atrophy. Skeletal muscle atrophy is a common pathologic adaptation to skeletal muscle disuse (commonly called "disuse atrophy"). Tissue and organs especially susceptible to atrophy include skeletal muscle, cardiac muscle, secondary sex organs, and the brain.
Hypertrophy
Cellular hypertrophy is an increase in cell size and volume. If enough cells of an organ hypertrophy the whole organ will increase in size. Hypertrophy may involve an increase in intracellular protein as well as cytosol (intracellular fluid) and other cytoplasmic components. For example, adipocytes (fat cells) may expand in size by depositing more lipid within cytoplasmic vesicles. Thus in human adults, increases in body fat tissue occurs mostly by increases in the size of adipocytes, not by increases in the number of adipocytes. Hypertrophy may be caused by mechanical signals (e.g., stretch) or trophic signals (e.g., growth factors). An example of physiologic hypertrophy is in skeletal muscle with sustained weight bearing exercise. An example of pathologic hypertrophy is in cardia
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https://en.wikipedia.org/wiki/Low%20copy%20repeats
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Low copy repeats (LCRs), also known as segmental duplications (SDs), are DNA sequences present in multiple locations within a genome that share high levels of sequence identity.
Repeats
The repeats, or duplications, are typically 10–300 kb in length, and bear greater than 95% sequence identity. Though rare in most mammals, LCRs comprise a large portion of the human genome owing to a significant expansion during primate evolution. In humans, chromosomes Y and 22 have the greatest proportion of SDs: 50.4% and 11.9% respectively.
Misalignment of LCRs during non-allelic homologous recombination (NAHR) is an important mechanism underlying the chromosomal microdeletion disorders as well as their reciprocal duplication partners. Many LCRs are concentrated in "hotspots", such as the 17p11-12 region, 27% of which is composed of LCR sequence. NAHR and non-homologous end joining (NHEJ) within this region are responsible for a wide range of disorders, including Charcot–Marie–Tooth syndrome type 1A, hereditary neuropathy with liability to pressure palsies, Smith–Magenis syndrome, and Potocki–Lupski syndrome.
Detection
The two widely accepted methods for SD detection are:
1. Whole-genome assembly comparison (WGAC), in which regions of homology within the assembly are identified.
2. Whole-genome shotgun sequence detection (WSSD), in which the duplication of regions is inferred by increased read coverage at the site of segmental duplication.
See also
Pseudogenes
Molecular evolution
Comparative genomics
Inparanoid
Tandem exon duplication
1q21.1 copy number variations
Segmental duplication on the human Y chromosome
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https://en.wikipedia.org/wiki/Timeline%20of%20the%20nuclear%20program%20of%20Iran
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This is the timeline of the nuclear program of Iran.
1956–1979
1957: The United States and Iran sign a civil nuclear co-operation agreement as part of the U.S. Atoms for Peace program.
August 9, 1963: Iran signs the Partial nuclear test ban treaty (PTBT) and ratifies it on December 23, 1963.
1967: The Tehran Nuclear Research Centre is built and run by the Atomic Energy Organization of Iran (AEOI).
September 1967: The United States supplies 5.545 kg of enriched uranium, of which 5.165 kg contain fissile isotopes for fuel in a research reactor. The United States also supplies 112 g of plutonium, of which 104 g are fissile isotopes, for use as start-up sources for research reactor.
July 1968: Iran signs the Nuclear Non-Proliferation Treaty and ratifies it. It goes into effect on March 5, 1970.
1970s: Under the rule of Mohammad Reza Shah Pahlavi, plans are made to construct up to 20 nuclear power stations across the country with U.S. support and backing. Numerous contracts are signed with various Western firms, and the West German firm Kraftwerk Union (a subsidiary of Siemens AG) begins construction on the Bushehr power plant in 1974.
1974: the Atomic Energy Act of Iran was promulgated. The Act covers the activities for which the Atomic Energy Organization of Iran was established at that period. These activities included using atomic energy and radiation in industry, agriculture and service industries, setting up atomic power stations and desalination factories, producing source materials needed in atomic industries. This creates the scientific and technical infrastructure required for carrying out the said projects, as well as co-ordinating and supervising all matters pertaining to atomic energy in the country.
1974: The Shah lent $1 billion to the French Atomic Energy Commission to help build the Eurodif uranium processing company in Europe. In exchange, Iran received rights to 10% of the enriched uranium product, a right Iran never exercised. After a bitter
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https://en.wikipedia.org/wiki/Physical%20design%20%28electronics%29
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In integrated circuit design, physical design is a step in the standard design cycle which follows after the circuit design. At this step, circuit representations of the components (devices and interconnects) of the design are converted into geometric representations of shapes which, when manufactured in the corresponding layers of materials, will ensure the required functioning of the components. This geometric representation is called integrated circuit layout. This step is usually split into several sub-steps, which include both design and verification and validation of the layout.
Modern day Integrated Circuit (IC) design is split up into Front-end Design using HDLs and Back-end Design or Physical Design. The inputs to physical design are (i) a netlist, (ii) library information on the basic devices in the design, and (iii) a technology file containing the manufacturing constraints. Physical design is usually concluded by Layout Post Processing, in which amendments and additions to the chip layout are performed. This is followed by the Fabrication or Manufacturing Process where designs are transferred onto silicon dies which are then packaged into ICs.
Each of the phases mentioned above has design flows associated with them. These design flows lay down the process and guide-lines/framework for that phase. The physical design flow uses the technology libraries that are provided by the fabrication houses. These technology files provide information regarding the type of silicon wafer used, the standard-cells used, the layout rules (like DRC in VLSI), etc.
Divisions
Typically, the IC physical design is categorized into full custom and semi-custom design.
Full-Custom: Designer has full flexibility on the layout design, no predefined cells are used.
Semi-Custom: Pre-designed library cells (preferably tested with DFM) are used, designer has flexibility in placement of the cells and routing.
One can use ASIC for Full Custom design and FPGA for Semi-Custom design
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https://en.wikipedia.org/wiki/KMCI-TV
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KMCI-TV (channel 38) is an independent television station licensed to Lawrence, Kansas, United States, serving the Kansas City metropolitan area. It is owned by the E. W. Scripps Company alongside NBC affiliate KSHB-TV (channel 41). Both stations share studios on Oak Street in Kansas City, Missouri, while KMCI-TV's transmitter is located at the Blue River Greenway in the city's Hillcrest section. Despite Lawrence being KMCI-TV's city of license, the station maintains no physical presence there.
History
The station first signed on the air on February 1, 1988. Founded by Miller Broadcasting, it originally served as an affiliate of the Home Shopping Network (HSN).
In March 1996, KSHB owner Scripps Howard Broadcasting reached a deal to manage KMCI under a local marketing agreement. That August, KMCI then dropped much of its home shopping programming and rebranded as "38 Family Greats", with a family-oriented general entertainment format from 6:00 a.m. to midnight, with HSN programming being relegated to the overnight hours. The new KMCI lineup included an inventory of programs that KSHB owned but had not had time to air after it switched to NBC in 1994.
Exercising an option from the 1996 pact with Miller, Scripps bought KMCI outright for $14.6 million in 2000, forming a legal duopoly with KSHB. In 2002, KMCI dropped the "Family Greats" branding and simply branded by its channel number. In July 2003, coinciding with the move of its transmitter site from Lawrence toward Kansas City, the station officially became known as "38 the Spot".
Programming
Syndicated programs broadcast on KMCI as of September 2020 include Mike & Molly, Last Man Standing, Family Guy, Divorce Court and 2 Broke Girls, among others. KMCI features hosts that promote the station's programming, as well as local events during commercial breaks. Taunia Hottman was the first spokesperson for KMCI as "38 the Spot". Meredith Hoenes (who became a traffic reporter for KSHB-TV around this time) replaced Hott
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https://en.wikipedia.org/wiki/Renal%20blood%20flow
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In the physiology of the kidney, renal blood flow (RBF) is the volume of blood delivered to the kidneys per unit time. In humans, the kidneys together receive roughly 25% of cardiac output, amounting to 1.2 - 1.3 L/min in a 70-kg adult male.
It passes about 94% to the cortex. RBF is closely related to renal plasma flow (RPF), which is the volume of blood plasma delivered to the kidneys per unit time.
While the terms generally apply to arterial blood delivered to the kidneys, both RBF and RPF can be used to quantify the volume of venous blood exiting the kidneys per unit time. In this context, the terms are commonly given subscripts to refer to arterial or venous blood or plasma flow, as in RBFa, RBFv, RPFa, and RPFv. Physiologically, however, the differences in these values are negligible so that arterial flow and venous flow are often assumed equal.
Renal plasma flow
Renal plasma flow is the volume of plasma that reaches the kidneys per unit time. Renal plasma flow is given by the Fick principle:
This is essentially a conservation of mass equation which balances the renal inputs (the renal artery) and the renal outputs (the renal vein and ureter). Put simply, a non-metabolizable solute entering the kidney via the renal artery has two points of exit, the renal vein and the ureter. The mass entering through the artery per unit time must equal the mass exiting through the vein and ureter per unit time:
where Pa is the arterial plasma concentration of the substance, Pv is its venous plasma concentration, Ux is its urine concentration, and V is the urine flow rate. The product of flow and concentration gives mass per unit time.
As mentioned previously, the difference between arterial and venous blood flow is negligible, so RPFa is assumed to be equal to RPFv, thus
Rearranging yields the previous equation for RPF:
Measuring
Values of Pv are difficult to obtain in patients. In practice, PAH clearance is used instead to calculate the effective renal plasma flow (
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https://en.wikipedia.org/wiki/GridFTP
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GridFTP is an extension of the File Transfer Protocol (FTP) for grid computing. The protocol was defined within the GridFTP working group of the Open Grid Forum. There are multiple implementations of the protocol; the most widely used is that provided by the Globus Toolkit.
The aim of GridFTP is to provide a more reliable and high performance file transfer, for example to enable the transmission of very large files. GridFTP is used extensively within large science projects such as the Large Hadron Collider and by many supercomputer centers and other scientific facilities.
GridFTP also addresses the problem of incompatibility between storage and access systems. Previously, each data provider would make their data available in their own specific way, providing a library of access functions. This made it difficult to obtain data from multiple sources, requiring a different access method for each, and thus dividing the total available data into partitions. GridFTP provides a uniform way of accessing the data, encompassing functions from all the different modes of access, building on and extending the universally accepted FTP standard. FTP was chosen as a basis for it because of its widespread use, and because it has a well defined architecture for extensions to the protocol (which may be dynamically discovered).
Numerous GridFTP clients have been developed. The Globus Online software-as-a-service system is particularly popular.
Features of GridFTP
GridFTP integrates with the Grid Security Infrastructure, which provides authentication and encryption to file transfers, with user-specified levels of confidentiality and data integrity, also for cross-server transfers (what FTP calls the File eXchange Protocol, FXP).
GridFTP achieves much greater use of bandwidth than conventional data stream technology by using multiple simultaneous TCP streams. Files can be downloaded in pieces simultaneously from multiple sources; or even in separate parallel streams from the s
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https://en.wikipedia.org/wiki/Pomeranchuk%20Prize
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The Pomeranchuk Prize is an international award for theoretical physics, awarded annually since 1998 by the Institute for Theoretical and Experimental Physics (ITEP) from Moscow. It is named after Russian physicist Isaak Yakovlevich Pomeranchuk, who together with Landau established the Theoretical Physics Department of the Institute.
Laureates
2023 Yakir Aharonov and Arkady Tseytlin
2022 Luciano Maiani and Irina Aref'eva
2021 Larry McLerran and Alexei Starobinsky
2020 Sergio Ferrara and Mikhail Andrejewitsch Vasiliev
2019 Roger Penrose and Vladimir S. Popov
2018 Giorgio Parisi and Lev Pitaevskii
2017 Igor Klebanov and Juri Moissejewitsch Kagan
2016 Curtis J. Callan and Yuri A. Simonov
2015 Stanley J. Brodsky and Victor Fadin
2014 Leonid Keldysh and Alexander Zamolodchikov
2013 Mikhail Shifman and Andrei Slavnov
2012 Juan Martín Maldacena and Spartak Belyaev
2011 Heinrich Leutwyler and Semyon Gershtein
2010 André Martin and Valentine Zakharov
2009 Nicola Cabibbo and Boris Ioffe
2008 Leonard Susskind and Lev Okun
2007 Alexander Belavin and Yoichiro Nambu
2006 Vadim Kuzmin and Howard Georgi
2005 Iosif Khriplovich and Arkady Vainshtein
2004 Alexander F. Andreev and Alexander Polyakov
2003 Valery Rubakov and Freeman Dyson
2002 Ludvig Faddeev and Bryce Seligman DeWitt
2001 Lev Lipatov and Tullio Regge
2000 Evgenii Feinberg and James Daniel Bjorken
1999 Karen Ter-Martirosian and Gabriele Veneziano
1998 Aleksander Ilyich Akhiezer and Sidney Drell
See also
List of physics awards
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https://en.wikipedia.org/wiki/Carapace
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A carapace is a dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tortoises, the underside is called the plastron.
Crustaceans
In crustaceans, the carapace functions as a protective cover over the cephalothorax (i.e., the fused head and thorax, as distinct from the abdomen behind). Where it projects forward beyond the eyes, this projection is called a rostrum. The carapace is calcified to varying degrees in different crustaceans.
Zooplankton within the phylum Crustacea also have a carapace. These include Cladocera, ostracods, and isopods, but isopods only have a developed "cephalic shield" carapace covering the head.
Arachnids
In arachnids, the carapace is formed by the fusion of prosomal tergites into a single plate which carries the eyes, ocularium, ozopores (a pair of openings of the scent gland of Opiliones) and diverse phaneres.
In a few orders, such as Solifugae and Schizomida, the carapace may be subdivided. In Opiliones, some authors prefer to use the term carapace interchangeably with the term cephalothorax, which is incorrect usage, because carapace refers only to the dorsal part of the exoskeleton of the cephalothorax.
Alternative terms for the carapace of arachnids and their relatives, which avoids confusion with crustaceans, are prosomal dorsal shield and peltidium.
Turtles and tortoises
The carapace is the dorsal (back) convex part of the shell structure of a turtle, consisting primarily of the animal's rib cage, dermal armor, and scutes.
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https://en.wikipedia.org/wiki/Malaspina%20Expedition%202010
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The Malaspina circumnavigation expedition was an interdisciplinary research project to assess the impact of global change on the oceans and explore their biodiversity. The 250 scientists on board the Hespérides and Sarmiento de Gamboa embarked on an eight-month expedition (starting in December 2010) scientific research with training for young researchers - advancing marine science and fostering the public understanding of science.
The project was under the umbrella of the Spanish Ministry of Science and Innovation's Consolider – Ingenio 2010 programme and was led by the Spanish National Research Council (CSIC) with the support of the Spanish Navy. It is named after the original scientific Malaspina Expedition between 1789 and 1794, that was commanded by Alejandro Malaspina. Due to Malaspina's involvement in a conspiracy to overthrow the Spanish government, he was jailed upon his return and a large part of the expedition's reports and collections were put away unpublished, not to see the light again until late in the 20th century.
Objectives
Assessing the impact of global change on the oceans
Global change relates to the impact of human activities on the functioning of the biosphere. These include activities which, although performed locally, have effects on the functioning of the earth's system as a whole.
The ocean plays a central role in regulating the planet's climate and is its biggest sink of and other substances
produced by human activity.
The project will put together Colección Malaspina 2010, a collection of environmental and biological data and samples which will be available to the scientific community for it to evaluate the impacts of future global changes. This will be particularly valuable, for example, when new technologies allow levels of pollutants below current thresholds of detection to be evaluated.
Exploring the biodiversity of the deep ocean
Half the Earth's surface is covered by oceans over 3,000 metres deep, making them the biggest
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https://en.wikipedia.org/wiki/Point%20in%20polygon
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In computational geometry, the point-in-polygon (PIP) problem asks whether a given point in the plane lies inside, outside, or on the boundary of a polygon. It is a special case of point location problems and finds applications in areas that deal with processing geometrical data, such as computer graphics, computer vision, geographic information systems (GIS), motion planning, and computer-aided design (CAD).
An early description of the problem in computer graphics shows two common approaches (ray casting and angle summation) in use as early as 1974.
An attempt of computer graphics veterans to trace the history of the problem and some tricks for its solution can be found in an issue of the Ray Tracing News.
Ray casting algorithm
One simple way of finding whether the point is inside or outside a simple polygon is to test how many times a ray, starting from the point and going in any fixed direction, intersects the edges of the polygon.
If the point is on the outside of the polygon the ray will intersect its edge an even number of times. If the point is on the inside of the polygon then it will intersect the edge an odd number of times. The status of a point on the edge of the polygon depends on the details of the ray intersection algorithm.
This algorithm is sometimes also known as the crossing number algorithm or the even–odd rule algorithm, and was known as early as 1962. The algorithm is based on a simple observation that if a point moves along a ray from infinity to the probe point and if it crosses the boundary of a polygon, possibly several times, then it alternately goes from the outside to inside, then from the inside to the outside, etc. As a result, after every two "border crossings" the moving point goes outside. This observation may be mathematically proved using the Jordan curve theorem.
Limited precision
If implemented on a computer with finite precision arithmetics, the results may be incorrect if the point lies very close to that boundary, bec
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https://en.wikipedia.org/wiki/Pressure%20exchanger
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A pressure exchanger transfers pressure energy from a high pressure fluid stream to a low pressure fluid stream. Many industrial processes operate at elevated pressures and have high pressure waste streams. One way of providing a high pressure fluid to such a process is to transfer the waste pressure to a low pressure stream using a pressure exchanger.
One particularly efficient type of pressure exchanger is a rotary pressure exchanger. This device uses a cylindrical rotor with longitudinal ducts parallel to its rotational axis. The rotor spins inside a sleeve between two end covers. Pressure energy is transferred directly from the high pressure stream to the low pressure stream in the ducts of the rotor. Some fluid that remains in the ducts serves as a barrier that inhibits mixing between the streams. This rotational action is similar to that of an old fashioned machine gun firing high pressure bullets and it is continuously refilled with new fluid cartridges. The ducts of the rotor charge and discharge as the pressure transfer process repeats itself.
The performance of a pressure exchanger is measured by the efficiency of the energy transfer process and by the degree of mixing between the streams. The energy of the streams is the product of their flow volumes and pressures. Efficiency is a function of the pressure differentials and the volumetric losses (leakage) through the device computed with the following equation:
where Q is flow, P is pressure, L is leakage flow, HDP is high pressure differential, LDP is low pressure differential, the subscript B refers to the low pressure feed to the device and the subscript G refers to the high pressure feed to the device.
Mixing is a function of the concentrations of the species in the inlet streams and the ratio of flow volumes to the device.
Reverse osmosis
One application in which pressure exchangers are widely used is reverse osmosis (RO). In an RO system, pressure exchangers are used as energy recovery dev
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https://en.wikipedia.org/wiki/Robotic%20magnetic%20navigation
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Robotic magnetic navigation (RMN) (also called remote magnetic navigation) uses robotic technology to direct magnetic fields which control the movement of magnetic-tipped endovascular catheters into and through the chambers of the heart during cardiac catheterization procedures.
Devices
Because the human heart beats during ablation procedures, catheter stability can be affected by navigation technique. Magnetic fields created by RMN technology guide the tip of a catheter using a “pull” mechanism of action (as opposed to “push” with manual catheter navigation). Magnetic catheter navigation has been associated with greater catheter stability.
Medical use
Atrial fibrilation
As of 2015 there were two robotic catheterization systems on the market for atrial fibrilation; one of them used magnetic guidance.
After long-term follow up, RMN navigation has been associated with better procedural and clinical outcomes for AF ablation when compared with manual catheter navigation for cardiac ablation.
Ventricular tachycardia
RMN has been shown to be safe and effective for cardiac catheter ablation in various patient populations with ventricular tachycardia.
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https://en.wikipedia.org/wiki/Comparison%20of%20programming%20languages%20%28basic%20instructions%29
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This article compares a large number of programming languages by tabulating their data types, their expression, statement, and declaration syntax, and some common operating-system interfaces.
Conventions of this article
Generally, var, , or is how variable names or other non-literal values to be interpreted by the reader are represented. The rest is literal code. Guillemets ( and ) enclose optional sections. indicates a necessary (whitespace) indentation.
The tables are not sorted lexicographically ascending by programming language name by default, and that some languages have entries in some tables but not others.
Type identifiers
Integers
The standard constants and can be used to determine how many s and s can be usefully prefixed to and . The actual sizes of , , and are available as the constants , , and etc.
Commonly used for characters.
The ALGOL 68, C and C++ languages do not specify the exact width of the integer types , , , and (C99, C++11) , so they are implementation-dependent. In C and C++ , , and types are required to be at least 16, 32, and 64 bits wide, respectively, but can be more. The type is required to be at least as wide as and at most as wide as , and is typically the width of the word size on the processor of the machine (i.e. on a 32-bit machine it is often 32 bits wide; on 64-bit machines it is sometimes 64 bits wide). C99 and C++11 also define the exact-width types in the stdint.h header. See C syntax#Integral types for more information. In addition the types and are defined in relation to the address size to hold unsigned and signed integers sufficiently large to handle array indices and the difference between pointers.
Perl 5 does not have distinct types. Integers, floating point numbers, strings, etc. are all considered "scalars".
PHP has two arbitrary-precision libraries. The BCMath library just uses strings as datatype. The GMP library uses an internal "resource" type.
The value of is provided by the i
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https://en.wikipedia.org/wiki/C%20parity
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In physics, the C parity or charge parity is a multiplicative quantum number of some particles that describes their behavior under the symmetry operation of charge conjugation.
Charge conjugation changes the sign of all quantum charges (that is, additive quantum numbers), including the electrical charge, baryon number and lepton number, and the flavor charges strangeness, charm, bottomness, topness and Isospin (I3). In contrast, it doesn't affect the mass, linear momentum or spin of a particle.
Formalism
Consider an operation that transforms a particle into its antiparticle,
Both states must be normalizable, so that
which implies that is unitary,
By acting on the particle twice with the operator,
we see that and . Putting this all together, we see that
meaning that the charge conjugation operator is Hermitian and therefore a physically observable quantity.
Eigenvalues
For the eigenstates of charge conjugation,
.
As with parity transformations, applying twice must leave the particle's state unchanged,
allowing only eigenvalues of the so-called C-parity or charge parity of the particle.
Eigenstates
The above implies that for eigenstates, . Since antiparticles and particles have charges of opposite sign, only states with all quantum charges equal to zero, such as the photon and particle–antiparticle bound states like the neutral pion, η or positronium, are eigenstates of .
Multiparticle systems
For a system of free particles, the C parity is the product of C parities for each particle.
In a pair of bound mesons there is an additional component due to the orbital angular momentum. For example, in a bound state of two pions, π+ π− with an orbital angular momentum L, exchanging π+ and π− inverts the relative position vector, which is identical to a parity operation. Under this operation, the angular part of the spatial wave function contributes a phase factor of (−1)L, where L is the angular momentum quantum number associated with L.
.
With a two-ferm
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https://en.wikipedia.org/wiki/Graph%20algebra%20%28social%20sciences%29
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Graph algebra is systems-centric modeling tool for the social sciences. It was first developed by Sprague, Pzeworski, and Cortes as a hybridized version of engineering plots to describe social phenomena.
Notes and references
Algebra
Social science methodology
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https://en.wikipedia.org/wiki/Demand%20optimization
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Demand optimization is the application of processes and tools to maximize return on sales. This usually involves the application of mathematical modeling techniques using computer software.
It has particular applications in retail, where merchants wish to identify the best combination of price and promotion to achieve desired sales, gross margin, inventory or market share objectives.
The methods used are similar to those applied in the related field of supply chain optimization, where mathematical algorithms are applied to large databases of sales data to help predict future outcomes. In the case of demand optimization, as well as in house sales history, there may be competitive pricing information.
Because it is still a new field, authoritative data on the benefits of demand optimization is not widely available, although suppliers offer case studies of early adopters which claim rapid return on investment, especially in the optimization of the timing and level of price markdowns.
See also
Demand shortfall
Price
Profit maximization
Yield management
Price discrimination
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https://en.wikipedia.org/wiki/Cauchy%27s%20integral%20formula
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In mathematics, Cauchy's integral formula, named after Augustin-Louis Cauchy, is a central statement in complex analysis. It expresses the fact that a holomorphic function defined on a disk is completely determined by its values on the boundary of the disk, and it provides integral formulas for all derivatives of a holomorphic function. Cauchy's formula shows that, in complex analysis, "differentiation is equivalent to integration": complex differentiation, like integration, behaves well under uniform limits – a result that does not hold in real analysis.
Theorem
Let be an open subset of the complex plane , and suppose the closed disk defined as
is completely contained in . Let be a holomorphic function, and let be the circle, oriented counterclockwise, forming the boundary of . Then for every in the interior of ,
The proof of this statement uses the Cauchy integral theorem and like that theorem, it only requires to be complex differentiable. Since can be expanded as a power series in the variable
it follows that holomorphic functions are analytic, i.e. they can be expanded as convergent power series.
In particular is actually infinitely differentiable, with
This formula is sometimes referred to as Cauchy's differentiation formula.
The theorem stated above can be generalized. The circle can be replaced by any closed rectifiable curve in which has winding number one about . Moreover, as for the Cauchy integral theorem, it is sufficient to require that be holomorphic in the open region enclosed by the path and continuous on its closure.
Note that not every continuous function on the boundary can be used to produce a function inside the boundary that fits the given boundary function. For instance, if we put the function , defined for , into the Cauchy integral formula, we get zero for all points inside the circle. In fact, giving just the real part on the boundary of a holomorphic function is enough to determine the function up to an imaginary con
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https://en.wikipedia.org/wiki/Second%20wind%20%28sleep%29
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Second wind (or third wind, fourth wind, etc.), a colloquial name for the scientific term wake maintenance zone, is a sleep phenomenon in which a person, after a prolonged period of staying awake, temporarily ceases to feel drowsy, often making it difficult to fall asleep when exhausted. They are the result of circadian rhythms cycling into a phase of wakefulness. For example, many people experience the effects of a second wind in the early morning even after an entire night without sleep because it is the time when they would normally wake up.
While most "winds" coincide with the 24-hour cycle, those experiencing extended sleep deprivation over multiple days have been known to experience a "fifth day turning point".
Characteristics
The "second wind" phenomenon may have evolved as a survival mechanism as part of the fight-or-flight response, allowing sleep-deprived individuals briefly to function at a higher level than they would without sleep deprivation.
Performance enhancement
One study presented a series of tasks of increasing difficulty to 16 young adults who had not slept in 35 hours and observed heightened activity in several brain regions using magnetic resonance imaging. Researcher Sean P.A. Drummond commented that the ability to summon a second wind allowed them to "call on cognitive resources they have that they normally don't need to use to do a certain task". (He also noted that their performance, though an improvement considering their state of sleep deprivation, were below what it would be had they slept.)
Another study found significant improvement in the performance of 31 adults on various neurobehavioral tests after the onset of the wake maintenance zone as compared to their performance just three hours prior, despite the fact that the subjects had been awake longer. The improvement as test subjects caught another wind was even more pronounced on the second day of extended wakefulness. A later study reproduced similar results.
Duration
The wak
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https://en.wikipedia.org/wiki/Mir-282%20microRNA%20precursor%20family
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In molecular biology, mir-282 microRNA is a short RNA molecule. MicroRNAs function to regulate the expression levels of other genes by several mechanisms.
See also
MicroRNA
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https://en.wikipedia.org/wiki/Austin%20moving-knife%20procedures
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The Austin moving-knife procedures are procedures for equitable division of a cake. To each of n partners, they allocate a piece of the cake which this partner values as exactly of the cake. This is in contrast to proportional division procedures, which give each partner at least of the cake, but may give more to some of the partners.
When , the division generated by Austin's procedure is an exact division and it is also envy-free. Moreover, it is possible to divide the cake to any number k of pieces which both partners value as exactly 1/k. Hence, it is possible to divide the cake between the partners in any fraction (e.g. give 1/3 to Alice and 2/3 to George).
When , the division is neither exact nor envy-free, since each partner only values his own piece as , but may value other pieces differently.
The main mathematical tool used by Austin's procedure is the intermediate value theorem (IVT).
Two partners and half-cakes
The basic procedures involve partners who want to divide a cake such that each of them gets exactly one half.
Two knives procedure
For the sake of description, call the two players Alice and George, and assume the cake is rectangular.
Alice places one knife on the left of the cake and a second parallel to it on the right where she judges it splits the cake in two.
Alice moves both knives to the right in a way that the part between the two knives always contains half of the cake's value in her eyes (while the physical distance between the knives may change).
George says "stop!" when he thinks that half the cake is between the knives. How can we be sure that George can say "stop" at some point? Because if Alice reaches the end, she must have her left knife positioned where the right knife started. The IVT establishes that George must be satisfied the cake is halved at some point.
A coin is tossed to select between two options: either George receives the piece between the knives and Alice receives the two pieces at the flanks, or vice ver
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https://en.wikipedia.org/wiki/Elongated%20triangular%20bipyramid
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In geometry, the elongated triangular bipyramid (or dipyramid) or triakis triangular prism is one of the Johnson solids (), convex polyhedra whose faces are regular polygons. As the name suggests, it can be constructed by elongating a triangular bipyramid () by inserting a triangular prism between its congruent halves.
The nirrosula, an African musical instrument woven out of strips of plant leaves, is made in the form of a series of elongated bipyramids with non-equilateral triangles as the faces of their end caps.
Formulae
The following formulae for volume (), surface area () and height () can be used if all faces are regular, with edge length a:
Dual polyhedron
The dual of the elongated triangular bipyramid is called a triangular bifrustum and has 8 faces: 6 trapezoidal and 2 triangular.
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https://en.wikipedia.org/wiki/Medial%20pterygoid%20muscle
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The medial pterygoid muscle (or internal pterygoid muscle), is a thick, quadrilateral muscle of the face. It is supplied by the mandibular branch of the trigeminal nerve (V). It is important in mastication (chewing).
Structure
The medial pterygoid muscle consists of two heads. The bulk of the muscle arises as a deep head from just above the medial surface of the lateral pterygoid plate. The smaller, superficial head originates from the maxillary tuberosity and the pyramidal process of the palatine bone.
Its fibers pass downward, lateral, and posterior, and are inserted, by a strong tendinous lamina, into the lower and back part of the medial surface of the ramus and angle of the mandible, as high as the mandibular foramen. The insertion joins the masseter muscle to form a common tendinous sling which allows the medial pterygoid and masseter to be powerful elevators of the jaw.
Nerve supply
The medial pterygoid muscle is supplied by the medial pterygoid nerve, a branch of the mandibular nerve, itself a branch of the trigeminal nerve (V). This also supplies the tensor tympani muscle and the tensor veli palatini muscle. The medial pterygoid nerve is a main trunk from the mandibular nerve, before the division of the trigeminal nerve - this is unlike the lateral pterygoid muscle, and all other muscles of mastication which are supplied by the anterior division of the mandibular nerve.
Function
The medial pterygoid muscle has functions including elevating the mandible (closing the mouth), protruding the mandible, mastication (especially for when the maxillary teeth and the mandibular teeth are close together), and excursing the mandible (contralateral excursion occurs with unilateral contraction).
Additional images
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https://en.wikipedia.org/wiki/Hyperprosociality
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Hyperprosociality is extremely altruistic behavior towards unrelated individuals that has been described as a trait unique to Homo sapiens.
Definition
The term was introduced in 2015 by Curtis Marean as "extremely cooperative behavior with unrelated individuals, often for the benefit of others or society without expectation of payoff". Although originating from an evolutionary anthropological perspective, hyperprosociality has been utilized in modern pedagogy and psychology.
Perspectives
Archeological and anthropological perspective
The high level of cooperation utilized by modern Homo sapiens is unique to our species. It has been argued that this must have evolutionary origins. Explanations for our level of hyperprosociality vary, from food and hunting to cooperative breeding. To keep a gene pool diverse, interchanges between human tribes must have taken place, requiring stronger relationships. Similarly, warfare had the potential to unite some groups and create far-reaching social bonds that connected tribes. Apart from uniting to be able to stand stronger against other enemies, strategies and culture were shared as well. ‘willingness to take mortal risks as a fighter is not the only form of altruism that contributes to prevailing in intergroup contests; more altruistic and hence more cooperative groups may be more productive and sustain healthier, stronger, or more numerous members, for example, or make more effective use of information.’
It remains unclear whether one of the mentioned origins is the driving one. It is clear, however, that extreme social behaviors are from other kinds of different cultures. Hyperprosociality does not make groups interwoven to a set extend. It can come in many degrees, depending on the setting. The only clear distinction that can be made is the difference between basic sociality and far-reaching hyperprosociality, sometimes altruistic behavior. At the most basic level of sociality, we take care of our sick, injured, old, and
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https://en.wikipedia.org/wiki/Tensor%20algebra
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In mathematics, the tensor algebra of a vector space V, denoted T(V) or T(V), is the algebra of tensors on V (of any rank) with multiplication being the tensor product. It is the free algebra on V, in the sense of being left adjoint to the forgetful functor from algebras to vector spaces: it is the "most general" algebra containing V, in the sense of the corresponding universal property (see below).
The tensor algebra is important because many other algebras arise as quotient algebras of T(V). These include the exterior algebra, the symmetric algebra, Clifford algebras, the Weyl algebra and universal enveloping algebras.
The tensor algebra also has two coalgebra structures; one simple one, which does not make it a bialgebra, but does lead to the concept of a cofree coalgebra, and a more complicated one, which yields a bialgebra, and can be extended by giving an antipode to create a Hopf algebra structure.
Note: In this article, all algebras are assumed to be unital and associative. The unit is explicitly required to define the coproduct.
Construction
Let V be a vector space over a field K. For any nonnegative integer k, we define the kth tensor power of V to be the tensor product of V with itself k times:
That is, TkV consists of all tensors on V of order k. By convention T0V is the ground field K (as a one-dimensional vector space over itself).
We then construct T(V) as the direct sum of TkV for k = 0,1,2,…
The multiplication in T(V) is determined by the canonical isomorphism
given by the tensor product, which is then extended by linearity to all of T(V). This multiplication rule implies that the tensor algebra T(V) is naturally a graded algebra with TkV serving as the grade-k subspace. This grading can be extended to a Z-grading by appending subspaces for negative integers k.
The construction generalizes in a straightforward manner to the tensor algebra of any module M over a commutative ring. If R is a non-commutative ring, one can still perform the co
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https://en.wikipedia.org/wiki/Edmonds%27%20algorithm
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In graph theory, Edmonds' algorithm or Chu–Liu/Edmonds' algorithm is an algorithm for finding a spanning arborescence of minimum weight (sometimes called an optimum branching).
It is the directed analog of the minimum spanning tree problem.
The algorithm was proposed independently first by Yoeng-Jin Chu and Tseng-Hong Liu (1965) and then by Jack Edmonds (1967).
Algorithm
Description
The algorithm takes as input a directed graph where is the set of nodes and is the set of directed edges, a distinguished vertex called the root, and a real-valued weight for each edge .
It returns a spanning arborescence rooted at of minimum weight, where the weight of an arborescence is defined to be the sum of its edge weights, .
The algorithm has a recursive description.
Let denote the function which returns a spanning arborescence rooted at of minimum weight.
We first remove any edge from whose destination is .
We may also replace any set of parallel edges (edges between the same pair of vertices in the same direction) by a single edge with weight equal to the minimum of the weights of these parallel edges.
Now, for each node other than the root, find the edge incoming to of lowest weight (with ties broken arbitrarily).
Denote the source of this edge by .
If the set of edges does not contain any cycles, then .
Otherwise, contains at least one cycle.
Arbitrarily choose one of these cycles and call it .
We now define a new weighted directed graph in which the cycle is "contracted" into one node as follows:
The nodes of are the nodes of not in plus a new node denoted .
If is an edge in with and (an edge coming into the cycle), then include in a new edge , and define .
If is an edge in with and (an edge going away from the cycle), then include in a new edge , and define .
If is an edge in with and (an edge unrelated to the cycle), then include in a new edge , and define .
For each edge in , we remember which edge in it corresponds to.
Now
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https://en.wikipedia.org/wiki/Gyroelongated%20pentagonal%20pyramid
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In geometry, the gyroelongated pentagonal pyramid is one of the Johnson solids (). As its name suggests, it is formed by taking a pentagonal pyramid and "gyroelongating" it, which in this case involves joining a pentagonal antiprism to its base.
It can also be seen as a diminished icosahedron, an icosahedron with the top (a pentagonal pyramid, ) chopped off by a plane. Other Johnson solids can be formed by cutting off multiple pentagonal pyramids from an icosahedron: the pentagonal antiprism and metabidiminished icosahedron (two pyramids removed), and the tridiminished icosahedron (three pyramids removed).
Dual polyhedron
The dual of the gyroelongated pentagonal pyramid has 11 faces: 5 kites, 1 regular pentagonal and 5 irregular pentagons.
External links
Johnson solids
Pyramids and bipyramids
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https://en.wikipedia.org/wiki/Wine%20Museum%2C%20Ehnen
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The Wine Museum (Musée du Vin), located in Ehnen on the Luxembourg side of the Moselle, illustrates the art of wine-making with exhibits of traditional vintner's tools and bottling equipment together with old documents and photographs. The property was acquired by the state in 1974 and opened as a museum in 1978. It occupies the home of a former vintner with winemaking antiques and furnishings.
The museum
Standing close to the banks of the river, the 18th-century house belonged to the prosperous Wellenstein family. The premises also house a cooperage showing how barrels were made, a large wine press, a smithy and the former Ehnen office of weights and measures. The museum exhibits demonstrate the process of wine-making from growing the grapes to bottling the wine. Many of the items in the museum have been donated by local vintners. There is also a small vineyard with all the local grape varieties. As these grapes are grown on government land, the wine made from them is served at official functions such as embassy dinners.
The museum is open from April through October, and is one of the main sites of the annual Riesling Open wine festival.
See also
List of museums in Luxembourg
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https://en.wikipedia.org/wiki/Camfrog
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Camfrog is a video chat and instant messaging client that was created by Camshare in October 2003. The app allows users to contact others worldwide and find or create chat rooms to gather communities that share similar interests.
History
On October 19, 2010, it was announced that Paltalk acquired Camfrog.
In 2015, A new software called Ribbit was introduced, which allows users to meet others by swiping through live videos.
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https://en.wikipedia.org/wiki/Electron%20crystallography
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Electron crystallography is a method to determine the arrangement of atoms in solids using a transmission electron microscope (TEM). It can involve the use of high-resolution transmission electron microscopy images, electron diffraction patterns including convergent-beam electron diffraction or combinations of these. It has been successful in determining some bulk structures, and also surface structures. Two related methods are low-energy electron diffraction which has solved the structure of many surfaces, and reflection high-energy electron diffraction which is used to monitor surfaces often during growth.
Comparison with X-ray crystallography
It can complement X-ray crystallography for studies of very small crystals (<0.1 micrometers), both inorganic, organic, and proteins, such as membrane proteins, that cannot easily form the large 3-dimensional crystals required for that process. Protein structures are usually determined from either 2-dimensional crystals (sheets or helices), polyhedrons such as viral capsids, or dispersed individual proteins. Electrons can be used in these situations, whereas X-rays cannot, because electrons interact more strongly with atoms than X-rays do. Thus, X-rays will travel through a thin 2-dimensional crystal without diffracting significantly, whereas electrons can be used to form an image. Conversely, the strong interaction between electrons and protons makes thick (e.g. 3-dimensional > 1 micrometer) crystals impervious to electrons, which only penetrate short distances.
One of the main difficulties in X-ray crystallography is determining phases in the diffraction pattern. Because of the complexity of X-ray lenses, it is difficult to form an image of the crystal being diffracted, and hence phase information is lost. Fortunately, electron microscopes can resolve atomic structure in real space and the crystallographic structure factor phase information can be experimentally determined from an image's Fourier transform. The Fourier
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https://en.wikipedia.org/wiki/Contagium%20vivum%20fluidum
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Contagium vivum fluidum (Latin: "contagious living fluid") was a phrase first used to describe a virus, and underlined its ability to slip through the finest ceramic filters then available, giving it almost liquid properties. Martinus Beijerinck (1851–1931), a Dutch microbiologist and botanist, first used the term when studying the tobacco mosaic virus, becoming convinced that the virus had a liquid nature.
The word "virus", from the Latin for "poison", was originally used to refer to any infectious agent, and gradually became used to refer to infectious particles. Bacteria could be seen under microscope, and cultured on agar plates. In 1890, Louis Pasteur declared "tout virus est un microbe": "all infectious diseases are caused by microbes".
In 1892, Dmitri Ivanovsky discovered that the cause of tobacco mosaic disease could pass through Chamberland's porcelain filter. Infected sap, passed through the filter, retained its infectious properties. Ivanovsky thought the disease was caused by an extremely small bacteria, too small to see under microscope, which secreted a toxin. It was this toxin, he thought, which passed through the filter. However, he was unable to culture the purported bacteria.
In 1898, Beijerinck independently found the cause of the disease could pass through porcelain filters. He disproved Ivanovsky's toxin theory by demonstrating infection in series. He found that although he could not culture the infectious agent, it would diffuse through an agar gel. This diffusion inspired him to put forward the idea of a non-cellular "contagious living fluid", which he called a "virus". This was somewhere between a molecule and a cell.
Ivanovsky, irked that Beijerinck had not cited him, demonstrated that particles of ink could also diffuse through agar gel, thus leaving the particulate or fluid nature of the pathogen unresolved. Beijerinck's critics including Ivanovsky argued that the idea of a "contagious living fluid" was a contradiction in terms. Howeve
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https://en.wikipedia.org/wiki/Spin%20network
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In physics, a spin network is a type of diagram which can be used to represent states and interactions between particles and fields in quantum mechanics. From a mathematical perspective, the diagrams are a concise way to represent multilinear functions and functions between representations of matrix groups. The diagrammatic notation can thus greatly simplify calculations.
Roger Penrose described spin networks in 1971. Spin networks have since been applied to the theory of quantum gravity by Carlo Rovelli, Lee Smolin, Jorge Pullin, Rodolfo Gambini and others.
Spin networks can also be used to construct a particular functional on the space of connections which is invariant under local gauge transformations.
Definition
Penrose's definition
A spin network, as described in Penrose (1971), is a kind of diagram in which each line segment represents the world line of a "unit" (either an elementary particle or a compound system of particles). Three line segments join at each vertex. A vertex may be interpreted as an event in which either a single unit splits into two or two units collide and join into a single unit. Diagrams whose line segments are all joined at vertices are called closed spin networks. Time may be viewed as going in one direction, such as from the bottom to the top of the diagram, but for closed spin networks the direction of time is irrelevant to calculations.
Each line segment is labelled with an integer called a spin number. A unit with spin number n is called an n-unit and has angular momentum nħ/2, where ħ is the reduced Planck constant. For bosons, such as photons and gluons, n is an even number. For fermions, such as electrons and quarks, n is odd.
Given any closed spin network, a non-negative integer can be calculated which is called the norm of the spin network. Norms can be used to calculate the probabilities of various spin values. A network whose norm is zero has zero probability of occurrence. The rules for calculating norms and probabil
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https://en.wikipedia.org/wiki/Inverse%20dynamics
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Inverse dynamics is an inverse problem. It commonly refers to either inverse rigid body dynamics or inverse structural dynamics. Inverse rigid-body dynamics is a method for computing forces and/or moments of force (torques) based on the kinematics (motion) of a body and the body's inertial properties (mass and moment of inertia). Typically it uses link-segment models to represent the mechanical behaviour of interconnected segments, such as the limbs of humans or animals or the joint extensions of robots, where given the kinematics of the various parts, inverse dynamics derives the minimum forces and moments responsible for the individual movements. In practice, inverse dynamics computes these internal moments and forces from measurements of the motion of limbs and external forces such as ground reaction forces, under a special set of assumptions.
Applications
The fields of robotics and biomechanics constitute the major application areas for inverse dynamics.
Within robotics, inverse dynamics algorithms are used to calculate the torques that a robot's motors must deliver to make the robot's end-point move in the way prescribed by its current task. The "inverse dynamics problem" for robotics was solved by Eduardo Bayo in 1987. This solution calculates how each of the numerous electric motors that control a robot arm must move to produce a particular action. Humans can perform very complicated and precise movements, such as controlling the tip of a fishing rod well enough to cast the bait accurately. Before the arm moves, the brain calculates the necessary movement of each muscle involved and tells the muscles what to do as the arm swings. In the case of a robot arm, the "muscles" are the electric motors which must turn by a given amount at a given moment. Each motor must be supplied with just the right amount of electric current, at just the right time. Researchers can predict the motion of a robot arm if they know how the motors will move. This is known as the forw
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https://en.wikipedia.org/wiki/Circuit%20diagram
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A circuit diagram (or: wiring diagram, electrical diagram, elementary diagram, electronic schematic) is a graphical representation of an electrical circuit. A pictorial circuit diagram uses simple images of components, while a schematic diagram shows the components and interconnections of the circuit using standardized symbolic representations. The presentation of the interconnections between circuit components in the schematic diagram does not necessarily correspond to the physical arrangements in the finished device.
Unlike a block diagram or layout diagram, a circuit diagram shows the actual electrical connections. A drawing meant to depict the physical arrangement of the wires and the components they connect is called artwork or layout, physical design, or wiring diagram.
Circuit diagrams are used for the design (circuit design), construction (such as PCB layout), and maintenance of electrical and electronic equipment.
In computer science, circuit diagrams are useful when visualizing expressions using Boolean algebra.
Symbols
Circuit diagrams are pictures with symbols that have differed from country to country and have changed over time, but are now to a large extent internationally standardized. Simple components often had symbols intended to represent some feature of the physical construction of the device. For example, the symbol for a resistor dates back to the time when that component was made from a long piece of wire wrapped in such a manner as to not produce inductance, which would have made it a coil. These wirewound resistors are now used only in high-power applications, smaller resistors being cast from carbon composition (a mixture of carbon and filler) or fabricated as an insulating tube or chip coated with a metal film. The internationally standardized symbol for a resistor is therefore now simplified to an oblong, sometimes with the value in ohms written inside, instead of the zig-zag symbol. A less common symbol is simply a series of peaks o
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https://en.wikipedia.org/wiki/Binary%20splitting
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In mathematics, binary splitting is a technique for speeding up numerical evaluation of many types of series with rational terms. In particular, it can be used to evaluate hypergeometric series at rational points.
Method
Given a series
where pn and qn are integers, the goal of binary splitting is to compute integers P(a, b) and Q(a, b) such that
The splitting consists of setting m = [(a + b)/2] and recursively computing P(a, b) and Q(a, b) from P(a, m), P(m, b), Q(a, m), and Q(m, b). When a and b are sufficiently close, P(a, b) and Q(a, b) can be computed directly from pa...pb and qa...qb.
Comparison with other methods
Binary splitting requires more memory than direct term-by-term summation, but is asymptotically faster since the sizes of all occurring subproducts are reduced. Additionally, whereas the most naive evaluation scheme for a rational series uses a full-precision division for each term in the series, binary splitting requires only one final division at the target precision; this is not only faster, but conveniently eliminates rounding errors. To take full advantage of the scheme, fast multiplication algorithms such as Toom–Cook and Schönhage–Strassen must be used; with ordinary O(n2) multiplication, binary splitting may render no speedup at all or be slower.
Since all subdivisions of the series can be computed independently of each other, binary splitting lends well to parallelization and checkpointing.
In a less specific sense, binary splitting may also refer to any divide and conquer algorithm that always divides the problem in two halves.
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https://en.wikipedia.org/wiki/List%20of%20formulas%20in%20Riemannian%20geometry
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This is a list of formulas encountered in Riemannian geometry. Einstein notation is used throughout this article. This article uses the "analyst's" sign convention for Laplacians, except when noted otherwise.
Christoffel symbols, covariant derivative
In a smooth coordinate chart, the Christoffel symbols of the first kind are given by
and the Christoffel symbols of the second kind by
Here is the inverse matrix to the metric tensor . In other words,
and thus
is the dimension of the manifold.
Christoffel symbols satisfy the symmetry relations
or, respectively, ,
the second of which is equivalent to the torsion-freeness of the Levi-Civita connection.
The contracting relations on the Christoffel symbols are given by
and
where |g| is the absolute value of the determinant of the metric tensor . These are useful when dealing with divergences and Laplacians (see below).
The covariant derivative of a vector field with components is given by:
and similarly the covariant derivative of a -tensor field with components is given by:
For a -tensor field with components this becomes
and likewise for tensors with more indices.
The covariant derivative of a function (scalar) is just its usual differential:
Because the Levi-Civita connection is metric-compatible, the covariant derivatives of metrics vanish,
as well as the covariant derivatives of the metric's determinant (and volume element)
The geodesic starting at the origin with initial speed has Taylor expansion in the chart:
Curvature tensors
Definitions
(3,1) Riemann curvature tensor
(3,1) Riemann curvature tensor
Ricci curvature
Scalar curvature
Traceless Ricci tensor
(4,0) Riemann curvature tensor
(4,0) Weyl tensor
Einstein tensor
Identities
Basic symmetries
The Weyl tensor has the same basic symmetries as the Riemann tensor, but its 'analogue' of the Ricci tensor is zero:
The Ricci tensor, the Einstein tensor, and the traceless Ricci tensor are symmetric 2-tensors:
First Bianch
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https://en.wikipedia.org/wiki/Non-covalent%20interaction
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In chemistry, a non-covalent interaction differs from a covalent bond in that it does not involve the sharing of electrons, but rather involves more dispersed variations of electromagnetic interactions between molecules or within a molecule. The chemical energy released in the formation of non-covalent interactions is typically on the order of 1–5 kcal/mol (1000–5000 calories per 6.02 molecules). Non-covalent interactions can be classified into different categories, such as electrostatic, π-effects, van der Waals forces, and hydrophobic effects.
Non-covalent interactions are critical in maintaining the three-dimensional structure of large molecules, such as proteins and nucleic acids. They are also involved in many biological processes in which large molecules bind specifically but transiently to one another (see the properties section of the DNA page). These interactions also heavily influence drug design, crystallinity and design of materials, particularly for self-assembly, and, in general, the synthesis of many organic molecules.
The non-covalent interactions may occur between different parts of the same molecule (e.g. during protein folding) or between different molecules and therefore are discussed also as intermolecular forces.
Electrostatic interactions
Ionic
Ionic interactions involve the attraction of ions or molecules with full permanent charges of opposite signs. For example, sodium fluoride involves the attraction of the positive charge on sodium (Na+) with the negative charge on fluoride (F−). However, this particular interaction is easily broken upon addition to water, or other highly polar solvents. In water ion pairing is mostly entropy driven; a single salt bridge usually amounts to an attraction value of about ΔG =5 kJ/mol at an intermediate ion strength I, at I close to zero the value increases to about 8 kJ/mol. The ΔG values are usually additive and largely independent of the nature of the participating ions, except for transition metal io
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https://en.wikipedia.org/wiki/Chamaenerion%20latifolium
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Chamaenerion latifolium (formerly Epilobium latifolium, also called Chamerion latifolium) is a species of flowering plant in the evening primrose family known by the English common names dwarf fireweed and river beauty willowherb. It has a circumboreal distribution, appearing throughout the northern regions of the Northern Hemisphere, including subarctic and Arctic areas such as snowmelt-flooded gravel bars and talus, in a wide range of elevations. This is a perennial herb growing in clumps of leaves variable in size, shape, and texture above a woody caudex. The leaves are 1 to 10 centimeters long, lance-shaped to oval, pointed or rounded at the tips, and hairy to hairless and waxy. The inflorescence is a rough-haired raceme of nodding flowers with bright to deep pink, and occasionally white, petals up to 3 centimeters long. Behind the opened petals are pointed sepals. The fruit is an elongated capsule which may exceed 10 centimeters in length.
This arctic plant provides valuable nutrition for the Inuit, who eat the leaves raw, boiled with fat, or steeped in water for tea, the flowers and fruits raw, and as a salad with meals of seal and walrus blubber. The leaves and shoots are edible, tasting much like spinach, and is also known in the Canadian tundra as River Beauty.
It is the national flower of Greenland with the Greenlandic name niviarsiaq ("young girl").
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https://en.wikipedia.org/wiki/Integral%20Equations%20and%20Operator%20Theory
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Integral Equations and Operator Theory is a journal dedicated to operator theory and its applications to engineering and other mathematical sciences. As some approaches to the study of integral equations (theoretically and numerically) constitute a subfield of operator theory, the journal also deals with the theory of integral equations and hence of differential equations. The journal consists of two sections: a main section consisting of refereed papers and a second consisting of short announcements of important results, open problems, information, etc. It has been published monthly by Springer-Verlag since 1978. The journal is also available online by subscription.
The founding editor-in-chief of the journal, in 1978, was Israel Gohberg. Its current editor-in-chief is Christiane Tretter.
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https://en.wikipedia.org/wiki/Pseudodeficiency%20alleles
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A pseudodeficiency allele or pseudodeficiency mutation is a mutation that alters the protein product or changes the gene's expression, but without causing disease. For example, in the lysosomal storage diseases, patients with a pseudodeficiency allele show greatly reduced enzyme activity, yet they remain clinically healthy.
In medical genetics, a false positive result occurs in an enzyme assay test when test results are positive, but disease or morbidity is not present. One possible cause of false positive results is a pseudodeficiency allele. Disease may also be present, but at a subclinical level.
Examples
Tay–Sachs disease. Enzyme assay testing was especially effective among Ashkenazi Jews because fewer pseudodeficiency alleles are found in this population, as compared with the general population. Carrier screening has not been as reliable in the general population.
Metachromatic leukodystrophy. Low arylsulphatase A activity can occur in healthy individuals. This poses a challenge in genetic testing, making it difficult to distinguish between patients who are at risk of developing the disease and those who are healthy carriers of a pseudodeficiency mutation. Metachromatic leukodystrophy is a classic example of the difficulties caused by pseudodeficiency in carrier screening, because very high pseudodeficiency carrier frequencies have been detected in some populations.
Implications
A pseudodeficiency allele may indicate a deficiency of the enzyme assay method, or it may reflect incomplete understanding of the enzyme's activity.
The enzyme assay may be invalid because of differences between the natural substrate and an artificial substrate used in testing.
The gene may be expressed differently in different tissues, causing a positive result in the tissue that is tested even though no disease is present. Blood serum is often used for enzyme assay testing because it can be sampled inexpensively. Testing with other tissue types may produce more reliable res
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https://en.wikipedia.org/wiki/Cabibbo%E2%80%93Kobayashi%E2%80%93Maskawa%20matrix
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In the Standard Model of particle physics, the Cabibbo–Kobayashi–Maskawa matrix, CKM matrix, quark mixing matrix, or KM matrix is a unitary matrix which contains information on the strength of the flavour-changing weak interaction. Technically, it specifies the mismatch of quantum states of quarks when they propagate freely and when they take part in the weak interactions. It is important in the understanding of CP violation. This matrix was introduced for three generations of quarks by Makoto Kobayashi and Toshihide Maskawa, adding one generation to the matrix previously introduced by Nicola Cabibbo. This matrix is also an extension of the GIM mechanism, which only includes two of the three current families of quarks.
The matrix
Predecessor – the Cabibbo matrix
In 1963, Nicola Cabibbo introduced the Cabibbo angle () to preserve the universality of the weak interaction.
Cabibbo was inspired by previous work by Murray Gell-Mann and Maurice Lévy,
on the effectively rotated nonstrange and strange vector and axial weak currents, which he references.
In light of current concepts (quarks had not yet been proposed), the Cabibbo angle is related to the relative probability that down and strange quarks decay into up quarks ( || and || , respectively). In particle physics jargon, the object that couples to the up quark via charged-current weak interaction is a superposition of down-type quarks, here denoted by .
Mathematically this is:
or using the Cabibbo angle:
Using the currently accepted values for || and || (see below), the Cabibbo angle can be calculated using
When the charm quark was discovered in 1974, it was noticed that the down and strange quark could decay into either the up or charm quark, leading to two sets of equations:
or using the Cabibbo angle:
This can also be written in matrix notation as:
or using the Cabibbo angle
where the various || represent the probability that the quark of flavor decays into a quark of flavor . This 2×2 r
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https://en.wikipedia.org/wiki/Discrete%20modelling
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Discrete modelling is the discrete analogue of continuous modelling. In discrete modelling, formulae are fit to discrete data—data that could potentially take on only a countable set of values, such as the integers, and which are not infinitely divisible. A common method in this form of modelling is to use recurrence relations.
Applied mathematics
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https://en.wikipedia.org/wiki/Elevator%20algorithm
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The elevator algorithm, or SCAN, is a disk-scheduling algorithm to determine the motion of the disk's arm and head in servicing read and write requests.
This algorithm is named after the behavior of a building elevator, where the elevator continues to travel in its current direction (up or down) until empty, stopping only to let individuals off or to pick up new individuals heading in the same direction.
From an implementation perspective, the drive maintains a buffer of pending read/write requests, along with the associated cylinder number of the request, in which lower cylinder numbers generally indicate that the cylinder is closer to the spindle, and higher numbers indicate the cylinder is farther away.
Description
When a new request arrives while the drive is idle, the initial arm/head movement will be in the direction of the cylinder where the data is stored, either in or out. As additional requests arrive, requests are serviced only in the current direction of arm movement until the arm reaches the edge of the disk. When this happens, the direction of the arm reverses, and the requests that were remaining in the opposite direction are serviced, and so on.
Variations
One variation of this method ensures all requests are serviced in only one direction, that is, once the head has arrived at the outer edge of the disk, it returns to the beginning and services the new requests in this one direction only (or vice versa). This is known as the "Circular Elevator Algorithm" or C-SCAN. Although the time of the return seek is wasted, this results in more equal performance for all head positions, as the expected distance from the head is always half the maximum distance, unlike in the standard elevator algorithm where cylinders in the middle will be serviced as much as twice as often as the innermost or outermost cylinders.
Other variations include:
FSCAN
LOOK
C-LOOK
N-Step-SCAN
Example
The following is an example of how to calculate average disk seek ti
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https://en.wikipedia.org/wiki/OwnCloud
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ownCloud is an open-source software product for sharing and syncing of files in distributed and federated enterprise scenarios. It allows companies and remote end-users to organize their documents on servers, computers and mobile devices and work with them collaboratively, while keeping a centrally organized and synchronized state. ownCloud supports extensions like online document editing (Collabora, OnlyOffice, Microsoft 365 and Microsoft Online Office) and synchronization of calendars and contacts. Users can access data and documents through a web browser or a variety of client apps.
ownCloud 10 requires PHP v7.4, an older version that is no longer supported. The newer ownCloud Infinite Scale platform is compatible with more recent server software versions, however it may be incompatible with shared hosting environments.
History
ownCloud is a company from Nürnberg, Germany, focused on enterprise users of its software. The ownCloud project was started in January 2010 and the company was founded in 2011.
In 2016 one of the founders left the company, creating the fork Nextcloud. ownCloud GmbH continued operations, and in July 2016 secured financing from new investors and took over the business of the American company ownCloud Inc.
The current versions of ownCloud 10 have been built on PHP 7.4, whose support ended in November 2022. Thus, since December 2022, ownCloud has been maintaining an updated version of PHP 7.4 in its distribution, both for enterprise and community users.
In 2021, ownCloud published "Infinite Scale", developed with help from the European Organization for Nuclear Research (CERN), which is a complete rewrite in Go. CERN uses ownCloud with its EOS filesystem to handle () "12 petabytes of data in 1.4 billion files". In its third version, ownCloud Infinite Scale brings GDPR data export, compliance with accessibility standards of the WCAG, a file firewall that allows admins to block content from uploading, and an Antivirus API to the ICAP
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https://en.wikipedia.org/wiki/Immunostaining
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In biochemistry, immunostaining is any use of an antibody-based method to detect a specific protein in a sample. The term "immunostaining" was originally used to refer to the immunohistochemical staining of tissue sections, as first described by Albert Coons in 1941. However, immunostaining now encompasses a broad range of techniques used in histology, cell biology, and molecular biology that use antibody-based staining methods.
Techniques
Immunohistochemistry
Immunohistochemistry or IHC staining of tissue sections (or immunocytochemistry, which is the staining of cells), is perhaps the most commonly applied immunostaining technique. While the first cases of IHC staining used fluorescent dyes (see immunofluorescence), other non-fluorescent methods using enzymes such as peroxidase (see immunoperoxidase staining) and alkaline phosphatase are now used. These enzymes are capable of catalysing reactions that give a coloured product that is easily detectable by light microscopy. Alternatively, radioactive elements can be used as labels, and the immunoreaction can be visualized by autoradiography.
Tissue preparation or fixation is essential for the preservation of cell morphology and tissue architecture. Inappropriate or prolonged fixation may significantly diminish the antibody binding capability. Many antigens can be successfully demonstrated in formalin-fixed paraffin-embedded tissue sections. However, some antigens will not survive even moderate amounts of aldehyde fixation. Under these conditions, tissues should be rapidly fresh frozen in liquid nitrogen and cut with a cryostat. The disadvantages of frozen sections include poor morphology, poor resolution at higher magnifications, difficulty in cutting over paraffin sections, and the need for frozen storage. Alternatively, vibratome sections do not require the tissue to be processed through organic solvents or high heat, which can destroy the antigenicity, or disrupted by freeze thawing. The disadvantage of vibr
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https://en.wikipedia.org/wiki/Double%20integrator
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In systems and control theory, the double integrator is a canonical example of a second-order control system. It models the dynamics of a simple mass in one-dimensional space under the effect of a time-varying force input .
Differential equations
The differential equations which represent a double integrator are:
where both
Let us now represent this in state space form with the vector
In this representation, it is clear that the control input is the second derivative of the output . In the scalar form, the control input is the second derivative of the output .
State space representation
The normalized state space model of a double integrator takes the form
According to this model, the input is the second derivative of the output , hence the name double integrator.
Transfer function representation
Taking the Laplace transform of the state space input-output equation, we see that the transfer function of the double integrator is given by
Using the differential equations dependent on and , and the state space representation:
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https://en.wikipedia.org/wiki/World%20Geographic%20Reference%20System
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The World Geographic Reference System (GEOREF) is a geocode, a grid-based method of specifying locations on the surface of the Earth. GEOREF is essentially based on the geographic system of latitude and longitude, but using a simpler and more flexible notation. GEOREF was used primarily in aeronautical charts for air navigation, particularly in military or inter-service applications, but it is rarely seen today. However, GEOREF can be used with any map or chart that has latitude and longitude printed on it.
Quadrangles
GEOREF is based on the standard system of latitude and longitude, but uses a simpler and more concise notation. GEOREF divides the Earth's surface into successively smaller quadrangles, with a notation system used to identify each quadrangle within its parent. Unlike latitude/longitude, GEOREF runs in one direction horizontally, east from the 180° meridian; and one direction vertically, north from the South Pole. GEOREF can easily be adapted to give co-ordinates with varying degrees of precision, using a 2–12 character geocode.
GEOREF co-ordinates are defined by successive divisions of the Earth's surface, as follows:
The first level of GEOREF divides the world into quadrangles each measuring 15 degrees of longitude by 15 degrees of latitude; this results in 24 zones of longitude and 12 bands of latitude. A longitude zone is identified by a letter from A to Z (omitting I and O) starting at 180 degrees and progressing eastward through the full 360 degrees of longitude; a latitude band is identified by a letter from A through M (omitting I) northward from the south pole. Hence, any 15 degree quadrangle can be identified by two letters; the easting (longitude) is given first, followed by the northing (latitude). These two letters are the first two characters of a full GEOREF coordinate.
Each 15-degree quadrangle is further divided into smaller quadrangles, measuring 1 degree of longitude by 1 degree of latitude. These quadrangles are lettered A to
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https://en.wikipedia.org/wiki/Argument%20from%20authority
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An argument from authority (argumentum ab auctoritate), also called an appeal to authority, or argumentum ad verecundiam (argument against shame), is a form of argument in which the mere fact that an influential figure holds a certain position is used as evidence that the position itself is correct. While it is not a valid form of logical proof, it is a practical and sound way of obtaining knowledge that is generally likely to be correct when the authority is real, pertinent, and universally accepted.
Validity of the argument in deductive and inductive methods
In the deductive method
This argument has been considered a logical fallacy since its introduction by Locke and Whately. In particular, this is a form of genetic fallacy; in which the conclusion about the validity of a statement is justified by appealing to the characteristics of the person who is speaking, such as in the ad hominem fallacy. It is also called the ad verecundiam fallacy because it also appeals to the sentiment of shame in people who question the authorities' claims.
This qualification as a logical fallacy implies that this argument is invalid when using the deductive method, and therefore it can't be presented as infallible. In other words, it's logically invalid to prove a claim is true because an authority has said it. The explanation is simple: authorities can be wrong, and the only way of logically proving a claim is providing real evidence and/or a valid logical deduction of the claim from the evidence.
Other related logical fallacies
It is also a fallacious ad hominem argument to argue that a person presenting statements lacks authority and thus their arguments do not need to be considered. Other related fallacious arguments assume that a person without status or authority is inherently reliable. For instance, the appeal to poverty is the fallacy of thinking that someone is more likely to be correct because they are poor. When an argument holds that a conclusion is likely to be tru
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https://en.wikipedia.org/wiki/Exponential%20family
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In probability and statistics, an exponential family is a parametric set of probability distributions of a certain form, specified below. This special form is chosen for mathematical convenience, including the enabling of the user to calculate expectations, covariances using differentiation based on some useful algebraic properties, as well as for generality, as exponential families are in a sense very natural sets of distributions to consider. The term exponential class is sometimes used in place of "exponential family", or the older term Koopman–Darmois family. The terms "distribution" and "family" are often used loosely: specifically, an exponential family is a set of distributions, where the specific distribution varies with the parameter; however, a parametric family of distributions is often referred to as "a distribution" (like "the normal distribution", meaning "the family of normal distributions"), and the set of all exponential families is sometimes loosely referred to as "the" exponential family. They are distinct because they possess a variety of desirable properties, most importantly the existence of a sufficient statistic.
The concept of exponential families is credited to E. J. G. Pitman, G. Darmois, and B. O. Koopman in 1935–1936. Exponential families of distributions provide a general framework for selecting a possible alternative parameterisation of a parametric family of distributions, in terms of natural parameters, and for defining useful sample statistics, called the natural sufficient statistics of the family.
Definition
Most of the commonly used distributions form an exponential family or subset of an exponential family, listed in the subsection below. The subsections following it are a sequence of increasingly more general mathematical definitions of an exponential family. A casual reader may wish to restrict attention to the first and simplest definition, which corresponds to a single-parameter family of discrete or continuous probabilit
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https://en.wikipedia.org/wiki/AGK%20%28gene%29
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The human gene AGK encodes the enzyme mitochondrial acylglycerol kinase.
The protein encoded by this gene is a mitochondrial membrane protein involved in lipid and glycerolipid metabolism. It catalyzes the formation of phosphatidic and lysophosphatidic acids. Defects in this gene have been associated with mitochondrial DNA depletion syndrome 10.
Diseases associated with AGK include cataracts and cardiomyopathy. An important paralog of this gene is CERKL.
Structure
The AGK gene is located on the 7th chromosome, with its specific location being 7q34. The gene contains 18 exons. AGK encodes a 47.1 kDa protein that is composed of 422 amino acids; 32 peptides have been observed through mass spectrometry data.
Function
Acylglycerol kinase synthesizes phosphatidic and lysophosphatidic acids. The enzyme uses ATP to put a phosphate group on acyl glycerol and diacylglycerol. It catalyzes the following reactions:
ATP + acylglycerol = ADP + acyl-sn-glycerol 3-phosphate.
ATP + 1,2-diacyl-sn-glycerol = ADP + 1,2-diacyl-sn-glycerol 3-phosphate.
The enzyme is involved in the more general pathway of fatty acid metabolism. AGK also has an implicated role in the assembly of the adenine nucleotide translocator in the inner mitochondrial membrane.
Clinical significance
Mutations in the AGK gene were the first to be implicated in isolated cataract development, although it is unclear whether these mutations cause a change in lipid composition of the lenses, or if signaling results in the defect. This gene has also been associated with Sengers syndrome. Two different phenotypes have been observed. One form of the disorder presented as vascular strokes, lactic acidosis, cardiomyopathy and cataracts, abnormal muscle cell histopathology and mitochondrial function. In those patients, there was also a markedly high rate of citrate synthase. The second phenotype presented with similar clinical symptoms, but no strokes. As phosphatidic acid is also involved in the synthesis of phospholipid
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https://en.wikipedia.org/wiki/Marlyn%20Meltzer
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Marlyn Wescoff Meltzer (1922 – December 7, 2008) was an American mathematician and computer programmer, and one of the six original programmers of ENIAC, the first general-purpose electronic digital computer.
Early life
Meltzer was born Marlyn Wescoff in Philadelphia in 1922. She graduated from Temple University in 1942.
Career
Meltzer was hired by the Moore School of Engineering after graduating to perform weather calculations, mainly because she knew how to operate an adding machine; in 1943, she was hired to perform calculations for ballistics trajectories. At the time, this was accomplished by using manual desktop mechanical calculators. In 1945, she was selected to become one of the 6 original programmers of Electronic Numerical Integrator and Computer.
ENIAC
Meltzer, alongside Kathleen Antonelli, Jean Jennings Bartik, Frances Elizabeth Holberton, Frances Spence and Ruth Teitelbaum, were the original six programmers of ENIAC, a project that originally began in secret at the Moore School of Electrical Engineering at the University of Pennsylvania in 1943.
ENIAC was a huge machine full of black panels and switches, containing 17,468 vacuum tubes, 7200 crystal diodes, 1500 relays, 70,000 resistors, 10,000 capacitors and approximately 5,000,000 hand-soldered joints. It weighed more than 30 short tons, occupied 167m2 and consumed 150 kW of electricity. Its huge power requirement led to a rumor that the lights across Philadelphia would dim every time it was switched on.
ENIAC was unveiled to the public on February 14, 1946, making headlines across the country.
Although mentioned in Woman of the ENIAC at the time, little recognition was attributed to the women working on the computer, with attention focused on the male engineers who built the machine. She resigned from the team in 1947 to get married before ENIAC was relocated to the Aberdeen Proving Grounds.
In 1997, Meltzer was inducted into the Women in Technology International Hall of Fame, along with th
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https://en.wikipedia.org/wiki/Procedural%20generation
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In computing, procedural generation (sometimes shortened as proc-gen) is a method of creating data algorithmically as opposed to manually, typically through a combination of human-generated content and algorithms coupled with computer-generated randomness and processing power. In computer graphics, it is commonly used to create textures and 3D models. In video games, it is used to automatically create large amounts of content in a game. Depending on the implementation, advantages of procedural generation can include smaller file sizes, larger amounts of content, and randomness for less predictable gameplay. Procedural generation is a branch of media synthesis.
Overview
The term procedural refers to the process that computes a particular function. Fractals are geometric patterns which can often be generated procedurally. Commonplace procedural content includes textures and meshes. Sound is often also procedurally generated, and has applications in both speech synthesis as well as music. It has been used to create compositions in various genres of electronic music by artists such as Brian Eno who popularized the term "generative music".
While software developers have applied procedural generation techniques for years, few products have employed this approach extensively. Procedurally generated elements have appeared in earlier video games: The Elder Scrolls II: Daggerfall takes place in a mostly procedurally generated world, giving a world roughly two thirds the actual size of the British Isles. Soldier of Fortune from Raven Software uses simple routines to detail enemy models, while its sequel featured a randomly generated level mode. Avalanche Studios employed procedural generation to create a large and varied group of detailed tropical islands for Just Cause. No Man's Sky, a game developed by games studio Hello Games, is all based upon procedurally generated elements.
The modern demoscene uses procedural generation to package a great deal of audiovisual content
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https://en.wikipedia.org/wiki/Fredholm%20module
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In noncommutative geometry, a Fredholm module is a mathematical structure used to quantize the differential calculus. Such a module is, up to trivial changes, the same as the abstract elliptic operator introduced by .
Definition
If A is an involutive algebra over the complex numbers C, then a Fredholm module over A consists of
an involutive representation of A on a Hilbert space H, together with a self-adjoint operator F, of square 1 and such that the commutator
[F, a]
is a compact operator, for all a in A.
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https://en.wikipedia.org/wiki/Poisson%27s%20equation
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Poisson's equation is an elliptic partial differential equation of broad utility in theoretical physics. For example, the solution to Poisson's equation is the potential field caused by a given electric charge or mass density distribution; with the potential field known, one can then calculate electrostatic or gravitational (force) field. It is a generalization of Laplace's equation, which is also frequently seen in physics. The equation is named after French mathematician and physicist Siméon Denis Poisson.
Statement of the equation
Poisson's equation is
where is the Laplace operator, and and are real or complex-valued functions on a manifold. Usually, is given, and is sought. When the manifold is Euclidean space, the Laplace operator is often denoted as , and so Poisson's equation is frequently written as
In three-dimensional Cartesian coordinates, it takes the form
When identically, we obtain Laplace's equation.
Poisson's equation may be solved using a Green's function:
where the integral is over all of space. A general exposition of the Green's function for Poisson's equation is given in the article on the screened Poisson equation. There are various methods for numerical solution, such as the relaxation method, an iterative algorithm.
Newtonian gravity
In the case of a gravitational field g due to an attracting massive object of density ρ, Gauss's law for gravity in differential form can be used to obtain the corresponding Poisson equation for gravity:
Since the gravitational field is conservative (and irrotational), it can be expressed in terms of a scalar potential ϕ:
Substituting this into Gauss's law,
yields Poisson's equation for gravity:
If the mass density is zero, Poisson's equation reduces to Laplace's equation. The corresponding Green's function can be used to calculate the potential at distance from a central point mass (i.e., the fundamental solution). In three dimensions the potential is
which is equivalent to Newton's law of
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https://en.wikipedia.org/wiki/Erin%20Blankenship
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Erin E. Blankenship is an American statistician interested in nonlinear models and environmental statistics, and known for her work in statistics education. She is a professor of statistics at the University of Nebraska–Lincoln.
Recognition
Blankenship is the 2013 winner of the Mu Sigma Rho William D. Warde Statistical Education Award, and in 2015 was elected as a Fellow of the American Statistical Association "for innovation and leadership in K-12 teacher development; for excellence in teaching, mentoring, and inspiring future teachers, teaching assistants, and statistics education researchers; and for interdisciplinary collaboration and service to the profession". In 2017, she was one of two winners of the highest teaching honor of the University of Nebraska system, the Outstanding Teaching and Instructional Creativity Award.
Education and research directions
Blankenship did her graduate studies at North Carolina State University, and credits an early female NCSU statistics professor, Gertrude Mary Cox, as a source of inspiration. Blankenship states that went into statistics because of its teamwork, and because, she says, "You’re applying science to find real solutions to real problems". Initially a research statistician, she gained her interest in statistics education after earning tenure at Nebraska.
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https://en.wikipedia.org/wiki/Tutor.com
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Tutor.com is an online tutoring company founded in 1998 that connects students to tutors in online classrooms. The service offers on-demand and scheduled tutoring to students, from fourth grade through college. Users can connect with live tutors of more than 40 subjects online, including math, science, essay writing, foreign language and test prep. As of 2020, the company has over 3,000 tutors.
Company history
Tutor.com was founded in 1998 by George Cigale. In its early years, the company focused on partnerships with libraries across the United States, which would provide online tutoring to its clients. Tutor.com expanded into multiple markets, including universities, employee benefits, the United States Department of Defense, and additional direct consumer services.
In January 2013, InterActive Corp (IAC) announced the purchase of Tutor.com, for an undisclosed amount. In August 2014, IAC's former subsidiary and Tutor.com's former parent Match Group bought test-preparation service The Princeton Review and combined it with its Tutor.com educational business. In March 2017, Match Group sold The Princeton Review, along with Tutor.com, to ST Unitas, a Korean education company. In January 2022, Primavera Capital Group acquired The Princeton Review and Tutor.com from ST Unitas.
The company has been featured prominently in The Wall Street Journal, Forbes, The New York Times and CNN when discussing the increasing trend of on-demand tutoring and educational technology.
U.S. military contract
In 2008, Tutor.com was awarded a contract with the United States Marine Corps to provide Marine families access to the service.
Since 2008, the program expanded to various branches within the U.S. military. As of 2020, Tutor.com for U.S. Military Families is a program funded by the funded by the U.S. Department of Defense and Coast Guard Mutual Assistance. The program provides eligible military service members and their dependents free, 24-hour access to online tutoring through Tuto
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https://en.wikipedia.org/wiki/Extinct%20species%20in%20art
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The artistic practice of depicting and representing extinct species can be in the form of painting, sculpture, photography, digital art, installation art, and various other artistic media. The practice dates back to prehistoric times and continues into the present day, with extinct species being depicted in both traditional and contemporary art. The significance of this practice lies in the exploration of themes like biodiversity loss, historical documentation, memory, and the ethics of extinction.
History
Art featuring extinct species can be traced back to cave paintings, such as the depiction of the woolly mammoth in the Lascaux cave in France. In the Middle Ages, mythical and real creatures that were possibly based on fossil remains, such as dragons and unicorns, became common in artwork and literature.
With the emergence of the concept of extinction in the 18th and 19th centuries, the art world began to take a different perspective on these extinct creatures. Natural history illustrations, such as those created by Charles R. Knight, started to incorporate extinct species based on scientific research, providing a glimpse into a world that no longer exists.
In the 20th and 21st centuries, with growing environmental awareness, artists have used extinct species to highlight issues of biodiversity loss and human impact on the environment.
Styles and themes
Artists often use extinct species in their work to communicate different themes and messages. This can range from a scientific or historical documentation of extinct creatures to an exploration of themes such as mortality, memory, and loss.
A common style is 'paleoart,' where artists strive to recreate extinct species and their environments as accurately as possible based on scientific evidence. This form of art is often used in museum displays, books, and educational materials.
Another style is more conceptual, using extinct species as symbols or metaphors. This is often seen in contemporary art, where the
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https://en.wikipedia.org/wiki/Cyber%20insurance
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Cyber-insurance is a specialty insurance product intended to protect businesses from Internet-based risks, and more generally from risks relating to information technology infrastructure and activities. Risks of this nature are typically excluded from traditional commercial general liability policies or at least are not specifically defined in traditional insurance products. Coverage provided by cyber-insurance policies may include first-party coverage against losses such as data destruction, extortion, theft, hacking, and denial of service attacks; liability coverage indemnifying companies for losses to others caused, for example, by errors and omissions, failure to safeguard data, or defamation; and other benefits including regular security-audit, post-incident public relations and investigative expenses, and criminal reward funds.
Advantages
Because the cyber-insurance market in many countries is relatively small compared to other insurance products, its overall impact on emerging cyber threats is difficult to quantify. As the impact to people and businesses from cyber threats is also relatively broad when compared to the scope of protection provided by insurance products, insurance companies continue to develop their services. According to a survey, 46% of all breaches have an effect on companies with fewer than 1,000 employees. In this case, strong security measures and cyber liability insurance may be necessary.
As insurers payout on cyber-losses, and as cyber threats develop and change, insurance products are increasingly being purchased alongside existing IT security services. Indeed, the underwriting criteria for insurers to offer cyber-insurance products are also early in development, and underwriters are actively partnering with IT security companies to develop their products.
As well as directly improving security, cyber-insurance is enormously beneficial in the event of a large-scale security breach. Insurance provides a smooth funding mechanism fo
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https://en.wikipedia.org/wiki/Nagata%20ring
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In commutative algebra, an N-1 ring is an integral domain whose integral closure in its quotient field is a finitely generated -module. It is called a Japanese ring (or an N-2 ring) if for every finite extension of its quotient field , the integral closure of in is a finitely generated -module (or equivalently a finite -algebra). A ring is called universally Japanese if every finitely generated integral domain over it is Japanese, and is called a Nagata ring, named for Masayoshi Nagata, or a pseudo-geometric ring if it is Noetherian and universally Japanese (or, which turns out to be the same, if it is Noetherian and all of its quotients by a prime ideal are N-2 rings). A ring is called geometric if it is the local ring of an algebraic variety or a completion of such a local ring , but this concept is not used much.
Examples
Fields and rings of polynomials or power series in finitely many indeterminates over fields are examples of Japanese rings. Another important example is a Noetherian integrally closed domain (e.g. a Dedekind domain) having a perfect field of fractions. On the other hand, a principal ideal domain or even a discrete valuation ring is not necessarily Japanese.
Any quasi-excellent ring is a Nagata ring, so in particular almost all Noetherian rings that occur in algebraic geometry are Nagata rings.
The first example of a Noetherian domain that is not a Nagata ring was given by .
Here is an example of a discrete valuation ring that is not a Japanese ring. Choose a prime and an infinite degree field extension of a characteristic field , such that . Let the discrete valuation ring be the ring of formal power series over whose coefficients generate a finite extension of . If is any formal power series not in then the ring is not an N-1 ring (its integral closure is not a finitely generated module) so is not a Japanese ring.
If is the subring of the polynomial ring in infinitely many generators generated by the squares and cubes of all
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https://en.wikipedia.org/wiki/Koolen%E2%80%93De%20Vries%20syndrome
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Koolen–De Vries syndrome (KdVS), also known as 17q21.31 microdeletion syndrome, is a rare genetic disorder caused by a deletion of a segment of chromosome 17 which contains six genes. This deletion syndrome was discovered independently in 2006 by three different research groups.
Presentation
The symptoms associated with this syndrome are variable, but common features include: low birthweight, low muscle tone at birth, poor feeding in infancy (often requiring feeding by tube for a period) and oromotor dyspraxia together with moderate developmental delays and learning disabilities but amiable behaviour. Other clinically important features include epilepsy, heart defects (atrial septal defect, ventricular septal defect) and kidney/urological anomalies. Silvery depigmentation of strands of hair have been noted in several patients. With age, there is an apparent coarsening of facial features.
17q21.3 was reported simultaneously in 2006 by three independent groups, with each group reporting several patients, and is now recognised to be one of the more common recurrent microdeletion syndromes. In 2007, a patient with a small duplication in same segment of DNA was described. An overview of the clinical features of the syndrome, by reviewing 22 individuals with a 17q21.31 microdeletion, estimated the disorder is present in 1 in every 16,000 people.
Genetics
The recurrent deletion is between 500 and 650 kilobases (Kb) in size encompassing at least six genes, among them the microtubule-associated protein tau (MAPT). A review of five patients found the parental chromosome from which the deletion originated carried a common 900kb inversion polymorphism. The orientation of low copy repeats flanking the deleted segment suggests the inversion in the parental chromosome influences the deletion in the child's chromosome via a non-allelic homologous recombination (NAHR) mechanism.
Affected genes
The deletion that causes this disease can remove up to six different genes. These inc
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https://en.wikipedia.org/wiki/Gert%20Mittring
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Gert Mittring (born 26 May 1966 in Stuttgart) is a German mental calculator. He was inspired by the late Wim Klein. He has competed in the MSO mental calculation event every year since 2004, failing to win the gold medal outright on only four occasions. He has held numerous world records for mental calculation, such as calculating the 89247th root of a 1000000 digit number. He has doctorates in statistics and mathematics education, and is a member of the Intelligence Research Committee of Intertel. Mittring is said to have been poor in math during his school years. He has written several books on mental calculation.
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https://en.wikipedia.org/wiki/Blastodisc
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The blastodisc, also called the germinal disc, is the embryo-forming part on the yolk of the egg of an animal that undergoes discoidal meroblastic cleavage. Discoidal cleavage occurs in those animals with a large proportion of yolk in their eggs, and include insects, fish, reptiles and birds. The blastodisc is a small disc of cytoplasm that sits on top of the yolk. In birds it is a small, circular, white spot (approximately 1.5-3 mm across) on the surface of the yellow yolk of an egg, at the animal pole.
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https://en.wikipedia.org/wiki/Bismuth%20telluride
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Bismuth telluride () is a gray powder that is a compound of bismuth and tellurium also known as bismuth(III) telluride. It is a semiconductor, which, when alloyed with antimony or selenium, is an efficient thermoelectric material for refrigeration or portable power generation. is a topological insulator, and thus exhibits thickness-dependent physical properties.
Properties as a thermoelectric material
Bismuth telluride is a narrow-gap layered semiconductor with a trigonal unit cell. The valence and conduction band structure can be described as a many-ellipsoidal model with 6 constant-energy ellipsoids that are centered on the reflection planes. cleaves easily along the trigonal axis due to Van der Waals bonding between neighboring tellurium atoms. Due to this, bismuth-telluride-based materials used for power generation or cooling applications must be polycrystalline. Furthermore, the Seebeck coefficient of bulk becomes compensated around room temperature, forcing the materials used in power-generation devices to be an alloy of bismuth, antimony, tellurium, and selenium.
Recently, researchers have attempted to improve the efficiency of -based materials by creating structures where one or more dimensions are reduced, such as nanowires or thin films. In one such instance n-type bismuth telluride was shown to have an improved Seebeck coefficient (voltage per unit temperature difference) of −287 μV/K at 54 °C, However, one must realize that Seebeck coefficient and electrical conductivity have a tradeoff: a higher Seebeck coefficient results in decreased carrier concentration and decreased electrical conductivity.
In another case, researchers report that bismuth telluride has high electrical conductivity of 1.1×105 S·m/m2 with its very low lattice thermal conductivity of 1.20 W/(m·K), similar to ordinary glass.
Properties as a topological insulator
Bismuth telluride is a well-studied topological insulator. Its physical properties have been shown to change at highly
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https://en.wikipedia.org/wiki/National%20Association%20for%20Continence
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National Association for Continence (NAFC) is a national, private, non-profit organization dedicated to improving the quality of life of people with incontinence, voiding dysfunction, and related pelvic floor disorders.
NAFC's purpose is to be the leading source for public education and advocacy about the causes, prevention, diagnosis, treatments, and management alternatives for incontinence.
History
The NAFC was established in 1982, and initially known as 'Help for Incontinent People'.
Objectives
NAFC's objectives are to destigmatize incontinence, to promote preventive measures, to motivate individuals to seek treatment, and to provide collaborative advocacy and service for those who are affected by this problem. To achieve its objectives, NAFC offers publications and services, such as: brochures detailing what every woman and man should know about bladder and bowel control, disease-specific booklets on multiple sclerosis, spinal cord injury, and Parkinson's disease, pelvic muscle exercise kits for men and women, Quality Care e-newsletter made up of articles written by leading professionals in the field, and a live webinar (online seminar) series that brings bladder and bowel health experts right to you. The National Association For Continence is supported by consumers/patients, health professionals, and industry.
Publications
NAFC has a series of educational resources relating to bladder problems.
General Audience: Bladder retraining, Urinary Catheterization of Men and Women, Fecal Incontinence, Incontinence and Odor Control, Overactive bladder.
For Women: Incontinence and Childbirth, Pelvic organ prolapse, Surgical Treatment for Female stress urinary incontinence, Non-Surgical Treatment for Female stress urinary incontinence (includes instructions for Pelvic Muscle Exercises).
For Men: Male stress incontinence, enlarged prostate, Incontinence: What Every Man Should Know (includes instructions for Pelvic Muscle Exercises).
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https://en.wikipedia.org/wiki/Moses%20Charikar
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Moses Samson Charikar is an Indian computer scientist who works as a professor at Stanford University. He was previously a professor at Princeton University. The topics of his research include approximation algorithms, streaming algorithms, and metric embeddings. He is known for the creation of the SimHash algorithm used by Google for near duplicate detection.
Charikar was born in Bombay, India, and competed for India at the 1990 and 1991 International Mathematical Olympiads, winning bronze and silver medals respectively. He did his undergraduate studies at the Indian Institute of Technology Bombay. In 2000 he completed a doctorate from Stanford University, under the supervision of Rajeev Motwani; he joined the Princeton faculty in 2001.
In 2012 he was awarded the Paris Kanellakis Award along with Andrei Broder and Piotr Indyk for their research on locality-sensitive hashing.
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https://en.wikipedia.org/wiki/PncA
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PncA is a gene encoding pyrazinamidase in Mycobacterium species. Pyrazinamidase converts the drug pyrazinamide to the active form pyrazinoic acid. There is a strong correlation between mutations in pncA and resistance of M. tuberculosis to pyrazinamide.
See also
Pyrazinamide
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https://en.wikipedia.org/wiki/Little%20Live%20%22Gotta%20Go%22%20Pets%20%28brand%29
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Little Live "Gotta Go" Pets is a sub-brand manufactured by the brand Moose Toys under its "Little Live" smart toy branding. The sub-brand is known for its highly interactive, technologically-developed toys of plush animals, most of which use the toilet or engage in toilet humor, reportedly to get child buyers interested in potty training. The "Gotta Go" line of toys, consisting of a flamingo and a turtle in psychedelic colours, were immensely popular in 2021, becoming a sought-after Christmas gift by western shoppers. The toys were also controversial and met with criticism, including by Doug Walker of Nostalgia Critic, who called the toys "disgusting" after viewing a television commercial for the turtle variant.
"Gotta Go" toy line
The Little Live Pets "Gotta Go" toy line began with a large plush "Little Live Gotta Go" flamingo printed in a psychedelic pink fabric with large anime-style eyes. The toy, named Sherbet (after the ice cream), had multiple functions so that its buyer could interact with it. It would "chat" (using smart cloud technology to record, store and play back its owner's voice), sing, dance, and make spastic movements. The toy became more widely-known, however, for its function whereby it would pass gas and make alarming noises; when placed on a plastic "potty" device, the toy would emit colourful fake feces into the potty that children could watch. This feces was created from coloured sand that is fed down the toy's throat from a large scoop so that the process can be repeated. The toy was followed up with Shelbert the "Little Live Gotta Go Turdle" (a portmanteau of "turd" and "turtle") that was printed in purple psychedelic fabric and had similar functions as Sherbet the flamingo.
Reception
The "Gotta Go" toy line was praised by magazines, parenting groups and websites both for its crude humor and for its educational value in getting young children interested in potty training. Parenting website Romper included the toy as its primary potty trai
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