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https://en.wikipedia.org/wiki/Bovine%20stool%20associated%20circular%20virus
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Bovine stool associated circular virus is a single stranded DNA virus with a circular genome that was isolated from bovine stool. It has also been isolated from pig stool. Therefore, Porcine stool-associated circular virus, a proposed species not yet been accepted by the ICTV, appears to be a synonym.
Virology
This virus was isolated from cows and pigs that appeared to be healthy.
Genome
The genome is a single stranded circular DNA molecule 2600 bases in length. It has two open reading frames encoding a replicase and capsid protein. The reading frames are arranged in opposite orientations on the genome. A stem loop is present between the 3' ends of the open reading frames. This is like chimpanzee stool associated circular virus and unlike any other known circular DNA virus.
Taxonomy
This virus appears to form a clade with the chimpanzee stool associated circular virus. Their relationship with other viruses is not yet known. The closest relations appear to be the Nanoviridae but further work is required to clarify this point.
However, Porcine stool-associated circular virus appears to be an unclassified member of ICTV-accepted genus Porprismacovirus in family Smacoviridae, same as chimpanzee stool associated circular virus. Nanoviridae and Smacoviridae are both members of class Arfiviricetes.
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https://en.wikipedia.org/wiki/GoldieBlox
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GoldieBlox is an American toy company that markets interactive toys designed for girls. GoldieBlox, which pairs a construction kit with a storybook, launched in 2012 as a prototype on Kickstarter. Its Kickstarter campaign led to more than $1 million in pre-orders placed in the first month. It went on to sell in retailers including Toys "R" Us and Amazon. None of the original construction kits or storybooks are still sold, with the company shifting its focus to crafting kits for girls.
The company was founded by Debbie Sterling, a Stanford engineering graduate and entrepreneur. The company is based in Los Angeles, California.
History
While a student at Stanford, Sterling noticed that the percentage of women in engineering in the United States was only 11%. After research, Sterling found that girls begin to lose interest in math and science as young as age 8. After two years studying early child development, including girls and the gender marketing of toys, Sterling learned that girls excel in verbal skills, reading and writing. She created GoldieBlox to combine the story of Goldie, a girl inventor who loves to build, with a construction kit.
To fund her first round of production, Sterling created a Kickstarter campaign in 2012. The project reached its funding goal of $150,000 in 4 days, and went on to raise a total of $285,881 with 5,519 backers by the end of the campaign.
Products
Geared toward ages 4–9, toys in the GoldieBlox series introduce engineering concepts to girls through storytelling and building. Each toy introduces new characters and concepts. There are six sets in the series.
In 2014, GoldieBlox began introducing digital content. The company's first mobile app, GoldieBlox and the Movie Machine, was introduced in October. The app features the company's first-ever animated cartoon, and was named by Apple as one of the Best Apps of 2014. Bloxtown, GoldieBlox's digital playground, also has original videos of new design ideas for kids to watch and bui
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https://en.wikipedia.org/wiki/Plant%20disease%20forecasting
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Plant disease forecasting is a management system used to predict the occurrence or change in severity of plant diseases. At the field scale, these systems are used by growers to make economic decisions about disease treatments for control. Often the systems ask the grower a series of questions about the susceptibility of the host crop, and incorporate current and forecast weather conditions to make a recommendation. Typically a recommendation is made about whether disease treatment is necessary or not. Usually treatment is a pesticide application.
Forecasting systems are based on assumptions about the pathogen's interactions with the host and environment, the disease triangle. The objective is to accurately predict when the three factors – host, environment, and pathogen – all interact in such a fashion that disease can occur and cause economic losses.
In most cases the host can be suitably defined as resistant or susceptible, and the presence of the pathogen may often be reasonably ascertained based on previous cropping history or perhaps survey data. The environment is usually the factor that controls whether disease develops or not. Environmental conditions may determine the presence of the pathogen in a particular season through their effects on processes such as overwintering. Environmental conditions also affect the ability of the pathogen to cause disease, e.g. a minimum leaf wetness duration is required for grey leaf spot of corn to occur. In these cases a disease forecasting system attempts to define when the environment will be conducive to disease development.
Good disease forecasting systems must be reliable, simple, cost-effective and applicable to many diseases. As such they are normally only designed for diseases that are irregular enough to warrant a prediction system, rather than diseases that occur every year for which regular treatment should be employed. Forecasting systems can only be designed if there is also an understanding on the
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https://en.wikipedia.org/wiki/Training%20masks
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Training masks are facial masks worn to limit the intake of air during breathing. Their ostensible purpose is to strengthen the respiratory musculature by making it work harder. There is some evidence that they may improve endurance capacity (VO2 max) and power output, but research into their benefits has so far generally proven inconclusive.
Training masks
Training masks allow users to actively work on their respiratory muscle fitness.
Originally designed to simulate training at altitude, the concept failed to deliver in multiple research trials. Training in hypoxic (low oxygen) environments increases red blood cell mass and improves oxygen transport, giving athletes a measurable performance boost when competing at sea level. The use of training masks, however, has no measurable effect on haemoglobin, hematocrit levels and oxygen transport in athletes, as they do not alter the oxygen concentration of the air taken in.
However, they appear to add resistance to the respiratory muscles by limiting air supply, thus triggering an adaptive physiological response. The muscles of respiration, from the diaphragm and the intercostals to the assisting musculature, need to be trained like any other muscles to increase resistance to fatigue and maximize performance. Respiratory Muscle Training (RMT) is a training method developed to condition the muscles of respiration specifically. RMT has been shown to markedly improve strength, speed, power and endurance in athletes. Preoperative Respiratory Muscle Training (RMT), or Inspiratory Muscle Training (IMT), is also used in the patients who are scheduled to undergo cardiac or abdominal surgery aiming to reduce the risk of postoperative pulmonary complications.
Training masks allow athletes to strengthen their respiratory muscle fitness without having to be confined to stationary devices or special facilities. By restricting the user's breathing, the devices may improve cardiorespiratory fitness, leading to better sport perform
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https://en.wikipedia.org/wiki/GHS%20hazard%20pictograms
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Hazard pictograms form part of the international Globally Harmonized System of Classification and Labelling of Chemicals (GHS). Two sets of pictograms are included within the GHS: one for the labelling of containers and for workplace hazard warnings, and a second for use during the transport of dangerous goods. Either one or the other is chosen, depending on the target audience, but the two are not used together. The two sets of pictograms use the same symbols for the same hazards, although certain symbols are not required for transport pictograms. Transport pictograms come in wider variety of colors and may contain additional information such as a subcategory number.
Hazard pictograms are one of the key elements for the labelling of containers under the GHS, along with:
an identification of the product;
a signal word – either Danger or Warning – where necessary
hazard statements, indicating the nature and degree of the risks posed by the product
precautionary statements, indicating how the product should be handled to minimize risks to the user (as well as to other people and the general environment)
the identity of the supplier (who might be a manufacturer or importer)
The GHS chemical hazard pictograms are intended to provide the basis for or to replace national systems of hazard pictograms. It has still to be implemented by the European Union (CLP regulation) in 2009.
The GHS transport pictograms are the same as those recommended in the UN Recommendations on the Transport of Dangerous Goods, widely implemented in national regulations such as the U.S. Federal Hazardous Materials Transportation Act (49 U.S.C. 5101–5128) and D.O.T. regulations at 49 C.F.R. 100–185.
Physical hazards pictograms
Health hazards pictograms
Physical and health hazard pictograms
Environmental hazards pictograms
Transport pictograms
Class 1: Explosives
Class 2: Gases
Classes 3 and 4: Flammable liquids and solids
Other GHS transport classes
Non-GHS transport pictograms
The fol
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https://en.wikipedia.org/wiki/FAM149B1
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The Family with sequence similarity 149 member B1 is an uncharacterized protein encoded by the human FAM149B1 gene, with one alias KIAA0974. The protein resides in the nucleus of the cell. The predicted secondary structure of the gene contains multiple alpha-helices, with a few beta-sheet structures. The gene is conserved in mammals, birds, reptiles, fish, and some invertebrates. The protein encoded by this gene contains a DUF3719 protein domain, which is conserved across its orthologues. The protein is expressed at slightly below average levels in most human tissue types, with high expression in brain, kidney, and testes tissues, while showing relatively low expression levels in pancreas tissues.
Gene
This gene has a possible 14 exons. It is located on the forward strand of chromosome 10 at 10q22.2 on the positive strand. The total span of the gene, including 5' and 3' UTR, is 3149 base pairs. The gene is flanked on the left by NUDT13 (nudix hydrolase 13) and on the right by DNAJC9-AS1 (DNAJC9 antisense RNA 1).
Isoforms
The FAM149B1 protein has a possible 10 isoforms, which are determined through alternative splicing of the gene.
Protein
General properties
The primary protein encoded by the FAM149B1 gene is 583 amino acids in length and has a molecular weight of 64 kDal. The protein contains a conserved protein domain, DUF3719 located at the amino acids 115–179. The isoelectric point of the protein before post-translational modifications is 6.3, and this isoelectric point is relatively conserved in the protein's isoforms, especially in those with the most similar composition of exons. This protein is considered serine rich, in that it expresses a higher serine composition relative to the composition of other human proteins. This high serine composition is also seen in the gene's orthologues.
Splice variants
The splice variants of the protein demonstrate some shared qualities of the protein that is translated from the primary transcript. Because each isofo
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https://en.wikipedia.org/wiki/Institute%20of%20Mathematics%2C%20Physics%2C%20and%20Mechanics
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Institute of Mathematics, Physics, and Mechanics (; IMFM) is the leading research institution in the areas of mathematics and theoretical computer science in Slovenia. It includes researchers from University of Ljubljana, University of Maribor and University of Primorska. It was founded in 1960.
The IMFM is composed of the following departments:
Department of Mathematrics
Department of Physics
Department of Theoretical Computer Science
The director is Jernej Kozak.
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https://en.wikipedia.org/wiki/Intracrine
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Intracrine refers to a hormone that acts inside a cell, regulating intracellular events. In simple terms it means that the cell stimulates itself by cellular production of a factor that acts within the cell. Steroid hormones act through intracellular (mostly nuclear) receptors and, thus, may be considered to be intracrines. In contrast, peptide or protein hormones, in general, act as endocrines, autocrines, or paracrines by binding to their receptors present on the cell surface. Several peptide/protein hormones or their isoforms also act inside the cell through different mechanisms. These peptide/protein hormones, which have intracellular functions, are also called intracrines. The term 'intracrine' is thought to have been coined to represent peptide/protein hormones that also have intracellular actions. To better understand intracrine, we can compare it to paracrine, autocrine and endocrine. The autocrine system deals with the autocrine receptors of a cell allowing for the hormones to bind, which have been secreted from that same cell. The paracrine system is one where nearby cells get hormones from a cell, and change the functioning of those nearby cells. The endocrine system refers to when the hormones from a cell affect another cell that is very distant from the one that released the hormone.
Paracrine physiology has been understood for decades now and the effects of paracrine hormones have been observed when for example, an obesity associate tumor will face the effects of local adipocytes, even if it is not in direct contact with the fat pads in concern. Endocrine physiology on the other hand is a growing field and has had a new area explored, called intracrinology. In intracrinology, the sex steroids produced locally, exert their action in the same cell where they are produced.
The biological effects produced by intracellular actions are referred as intracrine effects, whereas those produced by binding to cell surface receptors are called endocrine, autocrin
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https://en.wikipedia.org/wiki/Mitochondrial%20dicarboxylate%20carrier
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The mitochondrial dicarboxylate carrier (DIC) is an integral membrane protein encoded by the SLC25A10 gene in humans that catalyzes the transport of dicarboxylates such as malonate, malate, and succinate across the inner mitochondrial membrane in exchange for phosphate, sulfate, and thiosulfate by a simultaneous antiport mechanism, thus supplying substrates for the Krebs cycle, gluconeogenesis, urea synthesis, fatty acid synthesis, and sulfur metabolism.
Structure
The SLC25A10 gene is located on the q arm of chromosome 17 in position 25.3 and spans 8,781 base pairs. The gene has 11 exons and produces a 31.3 kDa protein composed of 287 amino acids. Intron 1 of this gene has five short Alu sequences. Mitochondrial dicarboxylate carriers are dimers, each consisting of six transmembrane domains with both the N- and C- terminus exposed to the cytoplasm. Like all mitochondrial carriers, dicarboxylate carriers features a tripartite structure with three repeats of about 100 amino acid residues, each of which contains a conserved sequence motif. These three tandem sequences fold into two anti-parallel transmembrane α-helices linked by hydrophilic sequences.
Function
A crucial function of dicarboxylate carriers is to export malate from the mitochondria in exchange for inorganic phosphate. Dicarboxylate carriers are highly abundant in the adipose tissue and play a central role in supplying cytosolic malate for the citrate transporter, which then exchanges cytosolic malate for mitochondrial citrate to begin fatty acid synthesis. Abundant levels of DIC are also detected in the kidneys and liver, whereas lower levels are found in the lung, spleen, heart, and brain. Dicarboxylate carriers are involved in glucose-stimulated insulin secretion through pyruvate cycling, which mediates NADPH production, and by providing cytosolic malate as a counter-substrate for citrate export. It is also involved in reactive oxygen species (ROS) production through hyperpolarization of mitochondri
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https://en.wikipedia.org/wiki/Centered%20octahedral%20number
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A centered octahedral number or Haüy octahedral number is a figurate number that counts the number of points of a three-dimensional integer lattice that lie inside an octahedron centered at the origin. The same numbers are special cases of the Delannoy numbers, which count certain two-dimensional lattice paths. The Haüy octahedral numbers are named after René Just Haüy.
History
The name "Haüy octahedral number" comes from the work of René Just Haüy, a French mineralogist active in the late 18th and early 19th centuries. His "Haüy construction" approximates an octahedron as a polycube, formed by accreting concentric layers of cubes onto a central cube. The centered octahedral numbers count the number of cubes used by this construction. Haüy proposed this construction, and several related constructions of other polyhedra, as a model for the structure of crystalline minerals.
Formula
The number of three-dimensional lattice points within n steps of the origin is given by the formula
The first few of these numbers (for n = 0, 1, 2, ...) are
1, 7, 25, 63, 129, 231, 377, 575, 833, 1159, ...
The generating function of the centered octahedral numbers is
The centered octahedral numbers obey the recurrence relation
They may also be computed as the sums of pairs of consecutive octahedral numbers.
Alternative interpretations
The octahedron in the three-dimensional integer lattice, whose number of lattice points is counted by the centered octahedral number, is a metric ball for three-dimensional taxicab geometry, a geometry in which distance is measured by the sum of the coordinatewise distances rather than by Euclidean distance. For this reason, call the centered octahedral numbers "the volume of the crystal ball".
The same numbers can be viewed as figurate numbers in a different way, as the centered figurate numbers generated by a pentagonal pyramid. That is, if one forms a sequence of concentric shells in three dimensions, where the first shell consists of a single po
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https://en.wikipedia.org/wiki/Wet-milling
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Wet-milling is a process in which feed material is steeped in water, with or without sulfur dioxide, to soften the seed kernel in order to help separate the kernel’s various components. For example, wet-milling plants can separate a 56-pound bushel of corn into more than 31 pounds of cornstarch (which in turn can be converted into corn syrups or corn ethanol), 15 pounds of corn gluten meal for use in animal feed, and nearly 2 pounds of corn oil.
See also
Corn steep liquor
Corn wet-milling
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https://en.wikipedia.org/wiki/441-line%20television%20system
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441-line is the number of scan lines in some early electronic monochrome analog television systems. Systems with this number of lines were used with 25 interlaced frames per second in France from 1937 to 1956, Germany from 1939 to 1943, Italy from 1939 to 1940, as well as by RCA in the United States with 30 interlaced frames per second from 1938 to 1941. Broadcasts were planned in Finland for 1940, but eventually cancelled due to World War II. Some experiments with similar systems were carried out on the USSR in the 1930s and Japan in 1939.
Germany
After trials with a 375-line system during the Berlin Olympic Games of 1936, by 1937 Germany had introduced a 441-line with 50 interlaced fields per second television system that replaced the previous 180 lines network relayed by a special Reichspost (National Post Office) cable network in the country's main cities (Berlin, Hamburg, Munich, Bayreuth, Nuremberg). The system's line frequency was 11.025 kHz and the broadcast frequencies were 46.0 MHz for vision and 43.2 MHz for sound, using a 4 MHz channel bandwidth. Its image aspect ratio was close to 1.15:1.
A project began in 1938 involving the National Post and several companies including Bosch, Blaupunkt, Loewe, Lorenz, and Telefunken that aimed to produce 10,000 receivers for the television system.
Telefunken marketed the FE V, announced in 1936, with a 26 x 21 cm screen and a tuning range of 38-60 MHz. The next year, 1937, the Heimprojektions-FSE was introduced, with a larger 50 x 40 cm screen, along with the FE VI with a 26 x 21 cm screen. In 1938, the Tischfernseher TF 1 was released, with a 20 x 17 cm screen and a tuning range of 40-55 MHz.
In 1937, Loewe created the FE-D, with a 24x20 cm screen and a tuning range of 35-55 MHz.
In 1938, TeKaDe created a single model, the FS38, with a 30 x 27 cm screen and a tuning range of 43-52 MHz. Other brands like Fernseh AG also created models like the DE 6, also introduced in 1938, with a 32 x 27 cm screen and a t
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https://en.wikipedia.org/wiki/Cerasicoccus
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Cerasicoccus is a Gram-negative, non-motile, obligately aerobic and chemoheterotrophic bacterial genus from the family Puniceicoccaceae.
See also
List of bacterial orders
List of bacteria genera
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https://en.wikipedia.org/wiki/Infant%20feeding
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Infant feeding is the practice of feeding infants. Breast milk provides the best nutrition when compared to infant formula. Infants are usually introduced to solid foods at around four to six months of age.
Breastfeeding aids in preventing anemia, obesity, and sudden infant death syndrome; and it promotes digestive health, immunity, intelligence, and dental development. The American Academy of Pediatrics recommends exclusively feeding an infant breast milk for the first six months of life and continuing for one year or longer as desired by infant and mother, and states that formula is an "acceptable substitute". Historically, breastfeeding infants was the only option for nutrition otherwise the infant would perish. Breastfeeding is rarely contraindicated, but is not recommended for mothers being treated for cancer, those with active tuberculosis, HIV, substance abuse, or leukemia. Clinicians can be consulted to determine what the best source of infant nutrition is for each baby.
Infant nutrition requirements
Proper infant nutrition demands providing essential substances that support normal growth, functioning, development, and resistance to infections and diseases. Optimal nutrition can be achieved by the expectant mother making the decision to breastfeed or bottle-feed the infant before birth and preparing for chosen decision.
Birth to six months
The World Health Organization (WHO) and the Pan American Health Organization currently recommend feeding infants only breast milk for the first six months of life. If the baby is being fed infant formula, it must be iron-enriched. An infant that receives exclusively breast milk for the first six months rarely needs additional vitamins or minerals. However, vitamins D and B12 may be needed if the breastfeeding mother does not have a proper intake of these vitamins. In fact, the American Academy of Pediatrics suggests all infants, breastfed or not, take a vitamin D supplement within the first days of life to prevent v
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https://en.wikipedia.org/wiki/Lethargy%20theorem
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In mathematics, a lethargy theorem is a statement about the distance of points in a metric space from members of a sequence of subspaces; one application in numerical analysis is to approximation theory, where such theorems quantify the difficulty of approximating general functions by functions of special form, such as polynomials. In more recent work, the convergence of a sequence of operators is studied: these operators generalise the projections of the earlier work.
Bernstein's lethargy theorem
Let be a strictly ascending sequence of finite-dimensional linear subspaces of a Banach space X, and let be a decreasing sequence of real numbers tending to zero. Then there exists a point x in X such that the distance of x to Vi is exactly .
See also
Bernstein's theorem (approximation theory)
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https://en.wikipedia.org/wiki/Thermoanaerobacter%20ethanolicus
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Thermoanaerobacter ethanolicus is a species of thermophilic, anaerobic, non-spore-forming bacteria.
The bacteria were first isolated from hot springs in Yellowstone National Park. The bacteria ferment sugars into ethanol and carbon dioxide more than other anaerobes, hence the species name ethanolicus. The growth range of T. ethanolicus is 37-77°C and pH 4.4-9.9, with the optimum growth temperature at around 70°C.
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https://en.wikipedia.org/wiki/Adolf%20Kussmaul
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Adolph Kußmaul (; 22 February 1822 – 28 May 1902) was a German physician and a leading clinician of his time. He was born as the son and grandson of physicians at Graben near Karlsruhe and studied at Heidelberg. He entered the army after graduation and spent two years as an army surgeon. This was followed by a period as a general practitioner before he went to Würzburg to study for his doctorate under Virchow.
He was subsequently Professor of Medicine at Heidelberg (1857), Erlangen (1859), Freiburg (1859) and Straßburg (1876).
Beyond his medical skills he was also active in literature. He is regarded as one of the creators of the term Biedermeier.
He died in Heidelberg.
Eponymous terms
His name continues to be used in eponyms. He described two medical signs and one disease which have eponymous names that remain in use:
Kussmaul breathing - Very deep and labored breathing with normal, rapid or reduced frequency seen in severe Diabetic ketoacidosis (DKA).
Kussmaul's sign - Paradoxical rise in the Jugular venous pressure (JVP) on inhalation in Constrictive pericarditis or Chronic obstructive pulmonary disease (COPD).
Kussmaul disease (Also called Kussmaul-Maier disease) - Polyarteritis nodosa. Named with Rudolf Robert Maier (1824-1888).
The following eponymous terms are considered archaic:
Kussmaul's coma - diabetic coma due to ketoacidosis.
Kussmaul's aphasia - selective mutism.
Firsts
First to describe dyslexia in 1877. (He called it 'word blindness'.)
First to describe polyarteritis nodosa.
First to describe progressive bulbar paralysis.
First to describe selective mutism.
First to diagnose mesenteric embolism.
First to perform pleural tapping and gastric lavage.
First to attempt oesophagoscopy and gastroscopy.
First to describe the emotional symptoms of mercury exposure as a first stage preceding the physical effects.
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https://en.wikipedia.org/wiki/Glass%20poling
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Glass poling is the physical process through which the distribution of the electrical charges is changed. In principle, the charges are randomly distributed and no permanent electric field exists inside the glass.
When the charges are moved and fixed at a place then a permanent field will be recorded in the glass. This electric field will permit various optical functions in the glass, impossible otherwise. The resulting effect would be like having positive and negative poles as in a battery, but inside an optical fibre.
The effect will be a change of the optical fibre properties. For instance glass poling will permit to realize second-harmonic light generation which consists of converting an input light into another wavelength, twice the original radiation frequency and half of the wave length. For instance a near infrared radiation around 1030 nm could be converted with this process to the 515 nm wavelength, corresponding to green light.
Glass poling also allows for the creation of the linear electro-optic effect that can be used for other functions like light modulation.
So, glass poling relies on recording an electric field which breaks the original symmetry of the material. Poling of glass is done by applying high voltage to the medium, while exciting it with heat, ultraviolet light or some other source of energy. Heat will permit the charges to move by diffusion and the high voltage permits to give a direction to the charges displacement.
Optical poling of silica fibers allows for second-harmonic generation through the creation of a self-organized periodic distribution of charges at the core-cladding interface.
UV poling received much attention because of the high non-linearity reported, but interest dwindled when various groups failed to reproduce the results.
Thermal poling
Strong electric fields are created by thermal poling of silica, subjecting the glass simultaneously to temperatures in the range of 280 °C and a few kilovolts bias for several mi
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https://en.wikipedia.org/wiki/Nuclear%20Weapons%3A%20The%20Road%20to%20Zero
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Nuclear Weapons: The Road to Zero is a 1998 book edited by Joseph Rotblat, a Polish physicist and 1995 Nobel Peace Prize laureate. The book is based on the Pugwash Conferences on Science and World Affairs, and in particular on a detailed international study published in 1993 on the importance of, and practical mechanisms to, eliminate nuclear weapons. This monograph is a series of essays that describe the many complex technical, economic, legal and political issues involved. Contrary to the approach of nuclear powers -- that these weapons are needed for national security -- is the "no longer fanciful dream" of a nuclear-weapon-free world. Rotblat suggests that this is "a sound and practical objective, which could be realized in the foreseeable future."
The book has 344 pages.
See also
List of books about nuclear issues
Nuclear disarmament
Anti-nuclear movement
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https://en.wikipedia.org/wiki/Rhizophagus%20irregularis
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Rhizophagus irregularis (previously known as Glomus intraradices) is an arbuscular mycorrhizal fungus used as a soil inoculant in agriculture and horticulture. Rhizophagus irregularis is also commonly used in scientific studies of the effects of arbuscular mycorrhizal fungi on plant and soil improvement. Until 2001, the species was known and widely marketed as Glomus intraradices, but molecular analysis of ribosomal DNA led to the reclassification of all arbuscular fungi from Zygomycota phylum to the Glomeromycota phylum.
Description
Spores
Color - white, cream, yellow-brown
Shape - elliptical with irregularities
Size - generally between 40 - 140 μm
Hyphae
Shape - Cylindrical or slightly flared
Size - Width: 11 - 18 μm
Identification
Rhizophagus irregularis colonization peaks earlier than many of the other fungi in Rhizophagus. There tends to be extensive hyphal networking and intense intraradical spores associated with older roots of host plants.
At times the spores are densely clustered or patchily distributed, depending on the host species. When the spores are heavily clustered, mycorrhizologists and others will tend to mistake G. intraradices for G. fasciculatum.
Reproduction
Rhizophagus irregularis (previously known as Glomus intraradices) has been found to colonise new plants by means of spores, hyphae or fragments of roots colonized by the fungus
Meiosis and recombination
Arbuscular mycorrhiza (AM) fungi were thought to have propagated clonally for over 500 million years because of their lack of visible sexual structures and thus were considered to be an ancient asexual lineage. However, homologs of 51 meiotic genes, including seven genes specific for meiosis were found to be conserved in the genomes of five AM species including Rhizophagus irregularis (referred to by its synonym designation Glomus irregulare). This observation suggests that the supposedly ancient asexual AM fungi are likely capable of undergoing a conventional meiosis. R. ir
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https://en.wikipedia.org/wiki/Metabolic%20equivalent%20of%20task
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The metabolic equivalent of task (MET) is the objective measure of the ratio of the rate at which a person expends energy, relative to the mass of that person, while performing some specific physical activity compared to a reference, currently set by convention at an absolute 3.5 mL of oxygen per kg per minute, which is the energy expended when sitting quietly by a reference individual, chosen to be roughly representative of the general population, and thereby suited to epidemiological surveys. A Compendium of Physical Activities is available online, which provides MET values for hundreds of activities.
A primary use of METs is to grade activity levels for common household activities (such as cleaning) and common exercise modalities (such as running). Vigorous household chores can add up to as much energy expenditure as dedicated exercise, so it is necessary to include both, suitably pro rata, in an assessment of general fitness.
An earlier convention defined the MET as a multiple of the resting metabolic rate (RMR) for the individual concerned. An individual's resting metabolic rate can be measured by absolute gas exchange, absolute thermal output, or steady-state diet in a sedentary condition (with no reference to body mass); or it can be estimated from age, sex, height, body mass, and estimated fitness level (which in part functions as a proxy for lean body mass). As a relative measure, it might correlate better with rating of perceived exertion. This definition is more common in colloquial use on the Internet concerning personal fitness, and less common in the recent academic literature. As a relative measure suited to judge exertion level for the individual athlete, many coaches now prefer a measure indexed to maximum heart rate, which is easy to monitor continuously with modern consumer electronics. Exercise equipment with an accurate delivered-wattage indicator permits the use of relative METs for the same purpose, assuming a known ratio of biological effi
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https://en.wikipedia.org/wiki/Eliteweb
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Elite Answers Inc., formerly named landofweebs, is a Toronto-based company that provides corporations and organisations with email marketing, web site development, search engine optimization and corporate social networking tools. Elite Answers began operations with the launch of the Eliteweb.cc search engine on October 11, 2005; the search engine was later renamed EliteAnswers.com. In 2006, the company expanded its offerings to include Elite Email, an e-mail marketing program for small businesses, and other Net-based services. In 2007, the company was named one of Canada's Top 20 Up and Comers by the Branham Group and Backbone Magazine. In 2009, Elite Email was rated one of the top 50 Email Service Providers by Website Magazine.
The company's president, Robert Burko, made front-page news in the Toronto Star in a heartfelt story titled "A heart attack, a wedding and an iPad" in which technology was used to save a wedding day after the father of the bride suffered a heart-attack 48 hours before the wedding.
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https://en.wikipedia.org/wiki/Remanence
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Remanence or remanent magnetization or residual magnetism is the magnetization left behind in a ferromagnetic material (such as iron) after an external magnetic field is removed. Colloquially, when a magnet is "magnetized", it has remanence. The remanence of magnetic materials provides the magnetic memory in magnetic storage devices, and is used as a source of information on the past Earth's magnetic field in paleomagnetism. The word remanence is from remanent + -ence, meaning "that which remains".
The equivalent term residual magnetization is generally used in engineering applications. In transformers, electric motors and generators a large residual magnetization is not desirable (see also electrical steel) as it is an unwanted contamination, for example a magnetization remaining in an electromagnet after the current in the coil is turned off. Where it is unwanted, it can be removed by degaussing.
Sometimes the term retentivity is used for remanence measured in units of magnetic flux density.
Types
Saturation remanence
The default definition of magnetic remanence is the magnetization remaining in zero field after a large magnetic field is applied (enough to achieve saturation). The effect of a magnetic hysteresis loop is measured using instruments such as a vibrating sample magnetometer; and the zero-field intercept is a measure of the remanence. In physics this measure is converted to an average magnetization (the total magnetic moment divided by the volume of the sample) and denoted in equations as Mr. If it must be distinguished from other kinds of remanence, then it is called the saturation remanence or saturation isothermal remanence (SIRM) and denoted by Mrs.
In engineering applications the residual magnetization is often measured using a B-H analyzer, which measures the response to an AC magnetic field (as in Fig. 1). This is represented by a flux density Br. This value of remanence is one of the most important parameters characterizing permanent ma
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https://en.wikipedia.org/wiki/Unsaturated%20fat
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An unsaturated fat is a fat or fatty acid in which there is at least one double bond within the fatty acid chain. A fatty acid chain is monounsaturated if it contains one double bond, and polyunsaturated if it contains more than one double bond.
A saturated fat has no carbon to carbon double bonds, so the maximum possible number of hydrogens bonded to the carbons, and is "saturated" with hydrogen atoms. To form carbon to carbon double bonds, hydrogen atoms are removed from the carbon chain. In cellular metabolism, unsaturated fat molecules contain less energy (i.e., fewer calories) than an equivalent amount of saturated fat. The greater the degree of unsaturation in a fatty acid (i.e., the more double bonds in the fatty acid) the more vulnerable it is to lipid peroxidation (rancidity). Antioxidants can protect unsaturated fat from lipid peroxidation.
Composition of common fats
In chemical analysis, fats are broken down to their constituent fatty acids, which can be analyzed in various ways. In one approach, fats undergo transesterification to give fatty acid methyl esters (FAMEs), which are amenable to separation and quantitation using by gas chromatography. Classically, unsaturated isomers were separated and identified by argentation thin-layer chromatography.
The saturated fatty acid components are almost exclusively stearic (C18) and palmitic acids (C16). Monounsaturated fats are almost exclusively oleic acid. Linolenic acid comprises most of the triunsaturated fatty acid component.
Chemistry and nutrition
Although polyunsaturated fats are protective against cardiac arrhythmias, a study of post-menopausal women with a relatively low fat intake showed that polyunsaturated fat is positively associated with progression of coronary atherosclerosis, whereas monounsaturated fat is not. This probably is an indication of the greater vulnerability of polyunsaturated fats to lipid peroxidation, against which vitamin E has been shown to be protective.
Examples
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https://en.wikipedia.org/wiki/Solvent%20exposure
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Solvent exposure occurs when a chemical, material, or person comes into contact with a solvent. Chemicals can be dissolved in solvents, materials such as polymers can be broken down chemically by solvents, and people can develop certain ailments from exposure to solvents both organic and inorganic.
Some common solvents include acetone, methanol, tetrahydrofuran, dimethylsulfoxide, and water among countless others.
In biology, the solvent exposure of an amino acid in a protein measures to what extent the amino acid is accessible to the solvent (usually water) surrounding the protein. Generally speaking, hydrophobic amino acids will be buried inside the protein and thus shielded from the solvent, while hydrophilic amino acids will be close to the surface and thus exposed to the solvent. However, as with many biological rules exceptions are common and hydrophilic residues are frequently found to be buried in the native structure and vice versa.
Solvent exposure can be numerically described by several measures, the most popular measures being accessible surface area and relative accessible surface area. Other measures are for example:
Contact number: number of amino acid neighbors within a sphere around the amino acid.
Residue depth: distance of the amino acid to the molecular surface.
Half sphere exposure: number of amino acid neighbors within two half spheres around the amino acid.
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https://en.wikipedia.org/wiki/Parallel%20slave%20port
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A parallel slave port (PSP) is an interface found on some PIC microcontrollers. It allows 8-bit asynchronous bidirectional data transfer between the PIC and external devices, such as other microcontrollers or personal computers.
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https://en.wikipedia.org/wiki/RSA%20SecurID
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RSA SecurID, formerly referred to as SecurID, is a mechanism developed by RSA for performing two-factor authentication for a user to a network resource.
Description
The RSA SecurID authentication mechanism consists of a "token"—either hardware (e.g. a key fob) or software (a soft token)—which is assigned to a computer user and which creates an authentication code at fixed intervals (usually 60 seconds) using a built-in clock and the card's factory-encoded almost random key (known as the "seed"). The seed is different for each token, and is loaded into the corresponding RSA SecurID server (RSA Authentication Manager, formerly ACE/Server) as the tokens are purchased. On-demand tokens are also available, which provide a tokencode via email or SMS delivery, eliminating the need to provision a token to the user.
The token hardware is designed to be tamper-resistant to deter reverse engineering. When software implementations of the same algorithm ("software tokens") appeared on the market, public code had been developed by the security community allowing a user to emulate RSA SecurID in software, but only if they have access to a current RSA SecurID code, and the original 64-bit RSA SecurID seed file introduced to the server. Later, the 128-bit RSA SecurID algorithm was published as part of an open source library. In the RSA SecurID authentication scheme, the seed record is the secret key used to generate one-time passwords. Newer versions also feature a USB connector, which allows the token to be used as a smart card-like device for securely storing certificates.
A user authenticating to a network resource—say, a dial-in server or a firewall—needs to enter both a personal identification number and the number being displayed at that moment on their RSA SecurID token. Though increasingly rare, some systems using RSA SecurID disregard PIN implementation altogether, and rely on password/RSA SecurID code combinations. The server, which also has a real-time clock and a d
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https://en.wikipedia.org/wiki/LarvalBase
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LarvalBase is a global online database of information about fish eggs, larvae and fry. It includes detailed data on the identification of very young fish and the rearing of fish species important for fisheries and aquaculture. , it included descriptions of 2,228 species, 4,229 pictures, and references to 4,513 works in the scientific literature. The database is under the supervision of Bernd Ueberschaer at the Leibniz Institute of Marine Sciences in Kiel, Germany.
LarvalBase is an offshoot of, and follows the same format as FishBase, a comprehensive online database about finfish. Whereas FishBase is a database about adult finfish, LarvalBase is a database about the juvenile stages of fish. Juvenile fish often feed differently and occupy different habitats than the adults do. LarvalBase complements FishBase by providing information about these early stages of life.
LarvalBase aims to include all the key data on finfish larvae, with an emphasis on standardising the data, making it easy to extract and combine data with other data, and offering powerful presentation tools. It draws on the traditional primary sources found in papers, books and reports, gray literature and unpublished but reliable data from sources such as practicing aquaculturists. The data includes information such as identification keys, morphometrics, broodstock, spawning and nursery behaviour, prey and predators, and growth stages and rates. It also includes information of specific interest to aquaculturists, such as how long it takes egg to hatch, diagrams charting changes in anatomy at different larval stages, analysis of larval diets, and techniques for rearing fish fry.
Background
It can be difficult for fisheries, aquaculture and hatchery scientists and managers to get the information they need on the species that concern them, because the relevant facts can be scattered and buried across numerous journal articles, reports, newsletters and other sources. It can be particularly difficult for p
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https://en.wikipedia.org/wiki/Aecium
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An aecium (plural aecia) is a specialised reproductive structure found in some plant pathogenic rust fungi that produce aeciospores. Aecia may also be referred to as "cluster cups". The term aecidium (plural aecidia) is used interchangeably but is not preferred.
In some rust fungi such as Phragmidium, aecia lack an outer wall structure (a peridium) but instead produce a diffuse aecium called a caeoma.
In some species of rust fungi with a life cycle including two different host plants, the binucleate spores produced in the aecia cannot infect the current plant host, but must infect a different plant species.
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https://en.wikipedia.org/wiki/Variable%20Assembly%20Language
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Variable Assembly Language (VAL) is a computer-based control system and language designed specifically for use with Unimation Inc. industrial robots.
The VAL robot language is permanently stored as a part of the VAL system. This includes the programming language used to direct the system for individual applications. The VAL language has an easy to understand syntax. It uses a clear, concise, and generally self-explanatory instruction set. All commands and communications with the robot consist of easy to understand word and number sequences. Control programs are written on the same computer that controls the robot. As a real-time system, VAL's continuous trajectory computation permits complex motions to be executed quickly, with efficient use of system memory and reduction in overall system complexity. The VAL system continuously generates robot control commands, and can simultaneously interact with a human operator, permitting on-line program generation and modification.
A convenient feature or VAL is the ability to use libraries or manipulation routines. Thus, complex operations may be easily and quickly programmed by combining predefined subtasks.
The VAL language consists of monitor commands and program instructions.
The monitor commands are used to prepare the system for execution of user-written programs. Program instructions provide the repertoire necessary to create VAL programs for controlling robot actions.
Terminology
The following terms are frequently used in VAL related operations.
Monitor
The VAL monitor is an administrative computer program that oversees operation of a system. It accepts user input and initiates the appropriate response; follows instructions from user-written programs to direct the robot; and performs the computations necessary to control the robot.
Editor
The VAL editor is an aid for entering information into a computer system, and modifying existing text. It is used to enter and modify robot control programs. It has a list of i
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https://en.wikipedia.org/wiki/Pi%20backbonding
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In chemistry, π backbonding, also called π backdonation, is when electrons move from an atomic orbital on one atom to an appropriate symmetry antibonding orbital on a π-acceptor ligand. It is especially common in the organometallic chemistry of transition metals with multi-atomic ligands such as carbon monoxide, ethylene or the nitrosonium cation. Electrons from the metal are used to bond to the ligand, in the process relieving the metal of excess negative charge. Compounds where π backbonding occurs include Ni(CO)4 and Zeise's salt.
IUPAC offers the following definition for backbonding:
A description of the bonding of π-conjugated ligands to a transition metal which involves a synergic process with donation of electrons from the filled π-orbital or lone electron pair orbital of the ligand into an empty orbital of the metal (donor–acceptor bond), together with release (back donation) of electrons from an nd orbital of the metal (which is of π-symmetry with respect to the metal–ligand axis) into the empty π*-antibonding orbital of the ligand.
Metal carbonyls, nitrosyls, and isocyanides
The electrons are partially transferred from a d-orbital of the metal to anti-bonding molecular orbitals of CO (and its analogues). This electron-transfer (i) strengthens the metal–C bond and (ii) weakens the C–O bond. The strengthening of the M–CO bond is reflected in increases of the vibrational frequencies for the M–C bond (often outside of the range for the usual IR spectrophotometers). Furthermore, the M–CO bond length is shortened. The weakening of the C–O bond is indicated by a decrease in the wavenumber of the νCO band(s) from that for free CO (2143 cm−1), for example to 2060 cm−1 in Ni(CO)4 and 1981 cm−1 in Cr(CO)6, and 1790 cm−1 in the anion [Fe(CO)4]2−. For this reason, IR spectroscopy is an important diagnostic technique in metal–carbonyl chemistry. The article infrared spectroscopy of metal carbonyls discusses this in detail.
Many ligands other than CO are strong "b
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https://en.wikipedia.org/wiki/Alpha%20beta%20filter
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An alpha beta filter (also called alpha-beta filter, f-g filter or g-h filter) is a simplified form of observer for estimation, data smoothing and control applications. It is closely related to Kalman filters and to linear state observers used in control theory. Its principal advantage is that it does not require a detailed system model.
Filter equations
An alpha beta filter presumes that a system is adequately approximated by a model having two internal states, where the first state is obtained by integrating the value of the second state over time. Measured system output values correspond to observations of the first model state, plus disturbances. This very low order approximation is adequate for many simple systems, for example, mechanical systems where position is obtained as the time integral of velocity. Based on a mechanical system analogy, the two states can be called position x and velocity v. Assuming that velocity remains approximately constant over the small time interval ΔT between measurements, the position state is projected forward to predict its value at the next sampling time using equation 1.
Since velocity variable v is presumed constant, its projected value at the next sampling time equals the current value.
If additional information is known about how a driving function will change the v state during each time interval, equation 2 can be modified to include it.
The output measurement is expected to deviate from the prediction because of noise and dynamic effects not included in the simplified dynamic model. This prediction error r is also called the residual or innovation, based on statistical or Kalman filtering interpretations
Suppose that residual r is positive. This could result because the previous x estimate was low, the previous v was low, or some combination of the two. The alpha beta filter takes selected alpha and beta constants (from which the filter gets its name), uses alpha times the deviation r to correct the position estim
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https://en.wikipedia.org/wiki/Felinology
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Felinology is the study of cats. The term is of Latin-Greek origin and comes from the Latin word (of cats, feline) and the Greek (science). Felinology is concerned with studying the anatomy, genetics, physiology, and breeding of domestic and wild cats.
Notes
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https://en.wikipedia.org/wiki/Hellinger%E2%80%93Toeplitz%20theorem
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In functional analysis, a branch of mathematics, the Hellinger–Toeplitz theorem states that an everywhere-defined symmetric operator on a Hilbert space with inner product is bounded. By definition, an operator A is symmetric if
for all x, y in the domain of A. Note that symmetric everywhere-defined operators are necessarily self-adjoint, so this theorem can also be stated as follows: an everywhere-defined self-adjoint operator is bounded. The theorem is named after Ernst David Hellinger and Otto Toeplitz.
This theorem can be viewed as an immediate corollary of the closed graph theorem, as self-adjoint operators are closed. Alternatively, it can be argued using the uniform boundedness principle. One relies on the symmetric assumption, therefore the inner product structure, in proving the theorem. Also crucial is the fact that the given operator A is defined everywhere (and, in turn, the completeness of Hilbert spaces).
The Hellinger–Toeplitz theorem reveals certain technical difficulties in the mathematical formulation of quantum mechanics. Observables in quantum mechanics correspond to self-adjoint operators on some Hilbert space, but some observables (like energy) are unbounded. By Hellinger–Toeplitz, such operators cannot be everywhere defined (but they may be defined on a dense subset). Take for instance the quantum harmonic oscillator. Here the Hilbert space is L2(R), the space of square integrable functions on R, and the energy operator H is defined by (assuming the units are chosen such that ℏ = m = ω = 1)
This operator is self-adjoint and unbounded (its eigenvalues are 1/2, 3/2, 5/2, ...), so it cannot be defined on the whole of L2(R).
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https://en.wikipedia.org/wiki/Mengenlehreuhr
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The Mengenlehreuhr (German for "Set Theory Clock") or Berlin-Uhr ("Berlin Clock") is the first public clock in the world that tells the time by means of illuminated, coloured fields, for which it entered the Guinness Book of Records upon its installation on 17 June 1975. Commissioned by the Senate of Berlin and designed by Dieter Binninger, the original full-sized Mengenlehreuhr was originally located at the Kurfürstendamm on the corner with Uhlandstraße. After the Senate decommissioned it in 1995, the clock was relocated to a site in Budapester Straße in front of Europa-Center, where it stands today.
Time encoding
The Mengenlehreuhr consists of 24 lights which are divided into one circular blinking yellow light on top to denote the seconds, two top rows denoting the hours and two bottom rows denoting the minutes.
The clock is read from the top row to the bottom. The top row of four red fields denote five full hours each, alongside the second row, also of four red fields, which denote one full hour each, displaying the hour value in 24-hour format. The third row consists of eleven yellow-and-red fields, which denote five full minutes each (the red ones also denoting 15, 30 and 45 minutes past), and the bottom row has another four yellow fields, which mark one full minute each. The round yellow light on top blinks to denote odd- (when lit) or even-numbered (when unlit) seconds.
Given the photo of the clock at the top of the article as an example, two fields are lit in the first row (five hours multiplied by two, i.e. ten hours), but no fields are lit in the second row; therefore the hour value is 10. Six fields are lit in the third row (five minutes multiplied by six, i.e. thirty minutes), while the bottom row has one field on (plus one minute). Hence, the lights of the clock altogether tell the time as 10:31.
Kryptos
This clock may be the key to the unsolved section of Kryptos, a sculpture at the CIA headquarters. After revealing that part of the deciphered tex
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https://en.wikipedia.org/wiki/Protein%20mass%20spectrometry
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Protein mass spectrometry refers to the application of mass spectrometry to the study of proteins. Mass spectrometry is an important method for the accurate mass determination and characterization of proteins, and a variety of methods and instrumentations have been developed for its many uses. Its applications include the identification of proteins and their post-translational modifications, the elucidation of protein complexes, their subunits and functional interactions, as well as the global measurement of proteins in proteomics. It can also be used to localize proteins to the various organelles, and determine the interactions between different proteins as well as with membrane lipids.
The two primary methods used for the ionization of protein in mass spectrometry are electrospray ionization (ESI) and matrix-assisted laser desorption/ionization (MALDI). These ionization techniques are used in conjunction with mass analyzers such as tandem mass spectrometry. In general, the proteins are analyzed either in a "top-down" approach in which proteins are analyzed intact, or a "bottom-up" approach in which protein are first digested into fragments. An intermediate "middle-down" approach in which larger peptide fragments are analyzed may also sometimes be used.
History
The application of mass spectrometry to study proteins became popularized in the 1980s after the development of MALDI and ESI. These ionization techniques have played a significant role in the characterization of proteins. (MALDI) Matrix-assisted laser desorption ionization was coined in the late 80's by Franz Hillenkamp and Michael Karas. Hillenkamp, Karas and their fellow researchers were able to ionize the amino acid alanine by mixing it with the amino acid tryptophan and irradiated with a pulse 266 nm laser. Though important, the breakthrough did not come until 1987. In 1987, Koichi Tanaka used the "ultra fine metal plus liquid matrix method" and ionized biomolecules the size of 34,472 Da protein carb
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https://en.wikipedia.org/wiki/Segment%20descriptor
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In memory addressing for Intel x86 computer architectures, segment descriptors are a part of the segmentation unit, used for translating a logical address to a linear address. Segment descriptors describe the memory segment referred to in the logical address.
The segment descriptor (8 bytes long in 80286 and later) contains the following fields:
A segment base address
The segment limit which specifies the segment size
Access rights byte containing the protection mechanism information
Control bits
Structure
The x86 and x86-64 segment descriptor has the following form:
Where the fields stand for:
Base Address Starting memory address of the segment. Its length is 32 bits and it is created from the lower part bits 16 to 31, and the upper part bits 0 to 7, followed by bits 24 to 31.
Segment Limit Its length is 20 bits and is created from the lower part bits 0 to 15 and the upper part bits 16 to 19. It defines the address of the last accessible data. The length is one more than the value stored here. How exactly this should be interpreted depends on the Granularity bit of the segment descriptor.
G=Granularity If clear, the limit is in units of bytes, with a maximum of 220 bytes. If set, the limit is in units of 4096-byte pages, for a maximum of 232 bytes.
D/B
D = Default operand size : If clear, this is a 16-bit code segment; if set, this is a 32-bit segment.
B = Big: If set, the maximum offset size for a data segment is increased to 32-bit 0xffffffff. Otherwise it's the 16-bit max 0x0000ffff. Essentially the same meaning as "D".
L=Long If set, this is a 64-bit segment (and D must be zero), and code in this segment uses the 64-bit instruction encoding. "L" cannot be set at the same time as "D" aka "B". (Bit 21 in the image)
AVL=Available For software use, not used by hardware (Bit 20 in the image with the label A)
P=Present If clear, a "segment not present" exception is generated on any reference to this segment
DPL=Descriptor privilege le
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https://en.wikipedia.org/wiki/Society%20of%20Physicists%20of%20Macedonia
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The Society of Physicists of Macedonia (, Drushtvo na Fizicharite na Republika Makedonija) is a scientific and educational organization established in 1949 in Skopje, Macedonia. It is located at the premises of the Institute of Physics at the Faculty of Natural Sciences and Mathematics at the Ss. Cyril and Methodius University.
The Society acts as a brokering organization between everyone who works in the field of physics or physical sciences in Macedonia. It also appears as the organizer of the regional (since 1967) and national (since 1957) competitions in physics for primary and secondary schools. Annually more than 500 students join this cycle of competitions and in the end the academic committee assigned by the Society chooses the best four students who comprise the Macedonian delegation to the International Physics Olympiad. The leader of the team is chosen among the Society's members and hitherto this duty was performed by Prof. Dr. Viktor Urumov (1995 - 2011 (leader) and 2014 - present (deputy leader)) and Mr. Stanisha Veljkovikj (2012 - ). Since the first time Macedonia sent a team to IPhO, its representatives have won a bronze medal and five honourable mentions.
The Society of Physicists administers the Biannual Conference of the Society of Physicists of Macedonia, which is often visited by many eminent physicists from various countries. The conferences usually last for three to five days.
Organization
The Society chooses its presidency and other notable posts among all its members once in two years at the regular annual meetings. The Society is organized to have an executive board, an academic committee (responsible for organizing the physics competitions) and an editorial board (for the Society's publications).
Among the members of the executive board the President, the Secretary and the Treasurer of the Society are elected. The current President of the society is Prof. Dr. Nace Stojanov.
Publications
The Society published two magazines: Impuls (Im
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https://en.wikipedia.org/wiki/The%20Rowett%20Institute
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The Rowett Institute is a research centre for studies into food and nutrition, located in Aberdeen, Scotland.
History
The institute was founded in 1913 when the University of Aberdeen and the North of Scotland College of Agriculture agreed that an "Institute for Research into Animal Nutrition" should be established in Scotland. The first director was John Boyd Orr, later to become Lord Boyd Orr, who moved from Glasgow to "the wilds of Aberdeenshire" in 1914. Orr drew up some plans for a nutrition research institute. Orr also donated £5000 for the building of a granite laboratory building at Craibstone, not far from the Bucksburn site of the Rowett.
At the breakout of the Great War, Orr left the institute, but returned in 1919 with a staff of four to begin work in the new laboratory. Orr continued to push for a new research institute and finally the Government agreed to pay half the costs but stipulated that the other half was to be found from other sources. The extra money was donated by Dr John Quiller Rowett, a businessman and director of a wine and spirits merchants in London.
Rowett's donation allowed the purchase of 41 acres of land for the institute to be built on. Rowett also contributed £10,000 towards the cost of the buildings. The money was donated with one very important stipulation from Rowett—"if any work done at the institute on animal nutrition were found to have a bearing on human nutrition, the institute would be allowed to follow up this work." The institute was formally opened in 1922 by Queen Mary.
In 1927, the Rowett was given £5000 to carry out an investigation to test whether health could be improved by the consumption of milk. After some further tests on other groups, a bill was passed in the House of Commons enabling local authorities in Scotland to provide cheap or free milk to all school children. It was soon applied in England too. This helped reduce the surplus of milk at the time and also helped rescue the milk industry which was i
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https://en.wikipedia.org/wiki/AVR%20Butterfly
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The AVR Butterfly is a battery-powered single-board microcontroller developed by Atmel. It consists of an Atmel ATmega169PV Microcontroller, a liquid crystal display, joystick, speaker, serial port, real-time clock (RTC), internal flash memory, and sensors for temperature and voltage. The board is the size of a name tag and has a clothing pin on back so it can be worn as such after the user enters their name onto the LCD.
Feature set
LCD
The AVRButterfly demonstrates LCD driving by running a 14 segment, six alpha-numeric character display. However, the LCD interface consumes many of the I/O pins.
CPU & Speed
The Butterfly's ATmega169 CPU is capable of speeds up to 8 MHz, however it is factory set by software to 2 MHz to preserve the button battery life. There are free replacement bootloaders available that will launch programs at 1, 2, 4 or 8 MHz speeds. Alternatively, this may be accomplished by changing the CPU prescaler in the application code.
Features
ATmega169V AVR 8-bit CPU, including 16 Kbyte of Flash memory for code storage and 512 bytes of EEPROM for data storage
100-segment LCD (without backlight)
4-Mbit (512-Kbyte) AT45 flash memory
4-way Mini-Joystick with center push-button
Light, temperature, and voltage (0-5 V range) sensors (light sensor no longer included due to the RoHS directive)
Piezo speaker
Solder pads for user-supplied connectors: 2 8-bit I/O ports, ISP, USI, JTAG
RS232 level converter & interface (Cable and connector provided by end user)
3 V battery holder (CR2450 battery included)
Software
The Butterfly comes preloaded with software that demonstrates many features of the ATmega169, including reading of the ambient light level and temperature and playback of musical notes. The device has a clothing-pin attached to the back, so it may be worn as a name tag — the "name" may be entered via the joystick or over the RS-232 port, and will scroll across the LCD.
Reprogramming
The Butterfly can be freely reprogrammed using
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https://en.wikipedia.org/wiki/Historiometry
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Historiometry is the historical study of human progress or individual personal characteristics, using statistics to analyze references to geniuses, their statements, behavior and discoveries in relatively neutral texts. Historiometry combines techniques from cliometrics, which studies economic history and from psychometrics, the psychological study of an individual's personality and abilities.
Origins
Historiometry started in the early 19th century with studies on the relationship between age and achievement by Belgian mathematician Adolphe Quetelet in the careers of prominent French and English playwrights but it was Sir Francis Galton, an English polymath who popularized historiometry in his 1869 work, Hereditary Genius. It was further developed by Frederick Adams Woods (who coined the term historiometry) in the beginning of the 20th century. Also psychologist Paul E. Meehl published several papers on historiometry later in his career, mainly in the area of medical history, although it is usually referred to as cliometric metatheory by him.
Historiometry was the first field studying genius by using scientific methods.
Current research
Prominent current historiometry researchers include Dean Keith Simonton and Charles Murray.
Historiometry is defined by Dean Keith Simonton as: a quantitative method of statistical analysis for retrospective data. In Simonton's work the raw data comes from psychometric assessment of famous personalities, often already deceased, in an attempt to assess creativity, genius and talent development.
Charles Murray's Human Accomplishment is one example of this approach to quantify the impact of individuals on technology, science and the arts. This work tracks many famous innovators in these areas, and quantifies how much attention to them has been paid by past historians, in terms of the number of references and the number of pages of reference material devoted to each subject. However, this work has been criticized for manipulating
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https://en.wikipedia.org/wiki/Pseudogynoxys%20chenopodioides
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Pseudogynoxys chenopodioides (syn. Senecio confusus), known commonly as the Mexican flamevine, is a climber in the family Asteraceae, native to Mexico, Central America and the West Indies.
Description
Pseudogynoxys chenopodioides is a fast-growing, twining, herbaceous vine with smooth stems and alternate arrowhead-shaped evergreen leaves sometimes reaching a height of ).
It features orange ray flowers (which age to a bright red), orange disc flowers, and ribbed fruits with persistent bristles that profusely appear from spring to fall. The plant will sporadically bloom all year-round in mild winter climates.
Cultivation
The Mexican flamevine is prized as an ornamental because of its showy flowers. It is widely grown in gardens in parts of the United States. It requires full sun, well-drained soil, and either a trellis or a shrub to climb on.
In colder areas, frost will kill the shoots, but the roots can survive the winter in most of the contiguous United States. It can be grown as an annual plant in a cold climate due to its rapid growth rate. If not grown as a vine, it will grow in a sprawling shrub-like form.
It is cultivated in Florida and has been reported as persisting after cultivation there, growing on disturbed sites. It is also sold under the name 'São Paulo', which is a cultivar with scarlet flowers.
P. chenopodioides is a nonhost of Digitivalva delaireae and this moth is an ineffective biocontrol of invasive Flame Vine Nonetheless, the plant is rarely bothered by any pests, therefore making it good for beginners.
Taxonomy
The plant's former scientific name Senecio confusus translates to "confused old man", which refers to the pappus bristles on the achenes and the vine's rampant habit of growth, respectively. Without support, a "confusion" of stems change the plant into a straggly shrub. Its current taxonomic name Pseudogynoxys chenopodioides refer to its "pseudo" resemblance to some of the species within the gynoxys and chenopodioideae genus.
Ga
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https://en.wikipedia.org/wiki/Medial%20calcaneal%20branches%20of%20the%20tibial%20nerve
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The medial calcaneal branches of the tibial nerve (internal calcaneal branches) perforate the laciniate ligament, and supply the skin of the heel and medial side of the sole of the foot.
Structure
The medial calcaneal nerve originates either from the tibial nerve or the lateral plantar nerve. It splits into two cutaneous branches.
Function
The medial calcaneal nerve provides sensory innervation to the medial side of the heel.
See also
Cutaneous innervation of the lower limbs
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https://en.wikipedia.org/wiki/Pervasive%20Software
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Pervasive Software was a company that developed software including database management systems and extract, transform and load tools. Pervasive Data Integrator and Pervasive Data Profiler are integration products, and the Pervasive PSQL relational database management system is its primary data storage product. These embeddable data management products deliver integration between corporate data, third-party applications and custom software.
Pervasive Software was headquartered in Austin, Texas, and sold its products with partners in other countries.
The company is involved in cloud computing through DataSolutions and its DataCloud offering along with its long-standing relationship with salesforce.com. It was acquired by Actian Corp. in April 2013.
History
Pervasive started in 1982 as SoftCraft developing the database management system technology Btrieve. Acquired by Novell in 1987, in January 1994 Pervasive spun out as Btrieve Technologies. The company name was changed to Pervasive Software in June 1996. Their initial public offering in 1997 raised $18.6 million.
Ron R. Harris was chief executive and founder Nancy R. Woodward was chairman of the board of directors (the other co-founder was her husband Douglas Woodward). Its shares were listed on the Nasdaq exchange under symbol PVSW.
Its database product was announced in 1999 as Pervasive.SQL version 7, and later renamed PSQL. PSQL implemented the atomicity, consistency, isolation, durability properties known as ACID using a relational database model.
In August 2003, Pervasive agreed to acquire Data Junction Corporation, makers of data and application integration tools renamed Pervasive Data Integrator, for about $51.7 million in cash and stock shares. Data Junction, founded in 1984, was a privately held company also headquartered in Austin. The merger closed in December 2003.
Pervasive also acquired business-to-business data interchange service Channelinx in August 2009. Based in Greenville, South Carolina
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https://en.wikipedia.org/wiki/Buttery%20%28room%29
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A buttery was originally a large cellar room under a monastery, in which food and drink were stored for the provisioning of strangers and passing guests. Nathan Bailey's An Universal Etymological English Dictionary gives "CELLARIST – one who keeps a Cella, or Buttery; the Butler in a religious House or Monastery." As the definition in John Stevens's The History of the Antient Abbeys shows, its initial function was to feed and water the guests rather than monks: "The Buttery; the Lodging for Guests". In a monastery a buttery was thus the place from which travellers would seek 'doles' of bread and weak ale, given at the exterior buttery door (and often via a small serving-hatch in the door, to prevent invasion of the stores by a crowd or by rough beggars). The task of doling out this free food and drink would be the role of the butterer. At larger monasteries there would also be a basic hostelry, where travellers could sleep for free.
Later the term buttery was also applied to a similar stores-room in a large medieval house, which might or might not be a cellar, and in which the buttery served the lord and his household rather than only passing travellers.
In both its uses, a buttery is to be distinguished from the butter and lard-house (pantry or larder), and the kitchen, a hostelry, or the refectory for guests or the dining hall for the inhabitants.
Etymology
In the Middle Ages, a buttery was a storeroom for liquor, the name being derived from the Latin and French words for bottle or, to put the word into its simpler form, a butt, that is, a cask. A butler, before he became able to take charge of the ewery, pantry, cellar, and the staff, would be in charge of the buttery. However, the origin of the word is extremely complex, and much that has been written on the subject is faulty.
Location
After the dissolution of the monasteries, the buttery in large houses and colleges became a place for barrels, bottles, or butts of alcoholic drink, and from which they were b
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https://en.wikipedia.org/wiki/Eternity
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Eternity, in common parlance, is an infinite amount of time that never ends or the quality, condition or fact of being everlasting or eternal. Classical philosophy, however, defines eternity as what is timeless or exists outside time, whereas sempiternity corresponds to infinite duration.
Philosophy
Classical philosophy defines eternity as what exists outside time, as in describing timeless supernatural beings and forces, distinguished from sempiternity which corresponds to infinite time, as described in requiem prayers for the dead. Some thinkers, such as Aristotle, suggest the eternity of the natural cosmos in regard to both past and future eternal duration. Boethius defined eternity as "simultaneously full and perfect possession of interminable life". Thomas Aquinas believed that God's eternity does not cease, as it is without either a beginning or an end; the concept of eternity is of divine simplicity, thus incapable of being defined or fully understood by humankind.
Thomas Hobbes (1588–1679) and many others in the Age of Enlightenment drew on the classical distinction to put forward metaphysical hypotheses such as "eternity is a permanent now".
Contemporary philosophy and physics
Today cosmologists, philosophers, and others look towards analyses of the concept from across cultures and history. They debate, among other things, whether an absolute concept of eternity has real application for fundamental laws of physics; compare the issue of the entropy as an arrow of time.
Religion
Eternity as infinite duration is an important concept in many lives and religions. God or gods are often said to endure eternally, or exist for all time, forever, without beginning or end. Religious views of an afterlife may speak of it in terms of eternity or eternal life. Christian theologians may regard immutability, like the eternal Platonic forms, as essential to eternity.
Symbolism
Eternity is often symbolized by the endless snake, swallowing its own tail, the ouro
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https://en.wikipedia.org/wiki/Matter
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In classical physics and general chemistry, matter is any substance that has mass and takes up space by having volume. All everyday objects that can be touched are ultimately composed of atoms, which are made up of interacting subatomic particles, and in everyday as well as scientific usage, matter generally includes atoms and anything made up of them, and any particles (or combination of particles) that act as if they have both rest mass and volume. However it does not include massless particles such as photons, or other energy phenomena or waves such as light or heat. Matter exists in various states (also known as phases). These include classical everyday phases such as solid, liquid, and gas – for example water exists as ice, liquid water, and gaseous steam – but other states are possible, including plasma, Bose–Einstein condensates, fermionic condensates, and quark–gluon plasma.
Usually atoms can be imagined as a nucleus of protons and neutrons, and a surrounding "cloud" of orbiting electrons which "take up space". However this is only somewhat correct, because subatomic particles and their properties are governed by their quantum nature, which means they do not act as everyday objects appear to act – they can act like waves as well as particles, and they do not have well-defined sizes or positions. In the Standard Model of particle physics, matter is not a fundamental concept because the elementary constituents of atoms are quantum entities which do not have an inherent "size" or "volume" in any everyday sense of the word. Due to the exclusion principle and other fundamental interactions, some "point particles" known as fermions (quarks, leptons), and many composites and atoms, are effectively forced to keep a distance from other particles under everyday conditions; this creates the property of matter which appears to us as matter taking up space.
For much of the history of the natural sciences people have contemplated the exact nature of matter. The idea tha
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https://en.wikipedia.org/wiki/Morchella%20septentrionalis
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Morchella septentrionalis species of fungus in the family Morchellaceae native North America. Described as new to science in 2012, it has a northerly eastern North American distribution, where it occurs north of 44°N. The fungus fruits under hardwoods, particularly American aspen (Populus grandidentata) and American ash (Fraxinus americana).
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https://en.wikipedia.org/wiki/V.%20Kumar%20Murty
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Vijaya Kumar Murty (born 20 May 1956) is an Indo-Canadian mathematician working primarily in number theory. He is a professor at the University of Toronto and is the Director of the Fields Institute.
Early life and education
V. Kumar Murty is the brother of mathematician M. Ram Murty.
Murty obtained his BSc in 1977 from Carleton University and his PhD in mathematics in 1982 from Harvard University under John Tate.
Career
From 1982 to 1987, he held research positions at the Institute for Advanced Study at Princeton, Concordia University, and the Tata Institute of Fundamental Research. In 1987, he was appointed as Associate Professor at the Downtown campus of the University of Toronto, and 1991 he was promoted to Full Professor. In 2001, he was deputed to the Mississauga campus to serve a two-year term as Associate Chair of Mathematics, and from 2004 to 2007 he served as the inaugural Chair of the newly-created Department of Mathematical and Computational Sciences at the Mississauga campus. Twice he was Chair of the Department of Mathematics at the University of Toronto Downtown campus (2008-2013 and 2014-2017).
Murty became the director of Fields Institute in 2019.
Murty has served on the Canadian Mathematical Society Board of Directors and as vice president of the Canadian Mathematical Society.
Research
Murty’s research is in areas of analytic number theory, algebraic number theory, information security, and arithmetic algebraic geometry. He and his brother, M. Ram Murty, have written more than 20 joint papers.
In 2020, Murty received a $666,667 grant from the Canadian Institutes of Health Research (CIHR) for setting up the COVID-19 Mathematical Modelling Rapid Response Task Force, a network of experts who will work to predict outbreak trajectories for the disease, measure public health interventions and provide real-time advice to policy-makers. It’s one of eight COVID-19 research projects at the University of Toronto.
Awards
Murty was elected a Fields In
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https://en.wikipedia.org/wiki/Institute%20of%20Applied%20Biochemistry
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The Institute of Applied Biochemistry is a research laboratory and bioweapons production facility located in Omutninsk, Kirov Oblast. For a time in the 1980s, the facility was directed by Ken Alibek.
Wild rodents like rats that live in the woods outside the factory are chronically infected with the "Schu-4 military strain" of tularemia due to a "small leak" in a basement pipe found in the twilight years of the USSR to be dripping a viral suspension into the ground.
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https://en.wikipedia.org/wiki/William%20Lawrence%20Kocay
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William Lawrence Kocay is a Canadian professor at the department of computer science at St. Paul's College of the University of Manitoba and a graph theorist. He is known for his work in graph algorithms and the reconstruction conjecture and is affectionately referred to as "Wild Bill" by his students. Bill Kocay is a former managing editor (from Jan 1988 to May 1997) of Ars Combinatoria, a Canadian journal of combinatorial mathematics, is a founding fellow of the Institute of Combinatorics and its Applications.
His research interests include algorithms for graphs, the development of mathematical software, the graph reconstruction problem, the graph isomorphism problem, projective geometry, Hamiltonian cycles, planarity, graph embedding algorithms, graphs on surfaces, and combinatorial designs.
Publications
Some new methods in reconstruction theory, W. L. Kocay – Combinatorial mathematics, IX (Brisbane, 1981), LNM
Some NP-complete problems for hypergraph degree sequences, CJ Colbourn, WL Kocay, DR Stinson – Discrete Applied Mathematics, 1986 – portal.acm.org
Books and software package
Graphs, algorithms, and optimization By William Kocay, Donald L. Kreher, Published 2004, CRC Press, 483 pages
Groups and graphs – A mainly Mac OS X software package for graphs, digraphs, combinatorial designs, projective configurations, polyhedra, graph embeddings in the torus and projective plane, and automorphism groups. It also constructs fractals.
See also
List of University of Waterloo people
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https://en.wikipedia.org/wiki/HFM1
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HFM1 is a gene that in humans encodes a protein necessary for homologous recombination of chromosomes. Biallelic mutations in HFM1 cause recessive primary ovarian insufficiency.
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https://en.wikipedia.org/wiki/Speech%20and%20language%20impairment
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Speech and language impairment are basic categories that might be drawn in issues of communication involve hearing, speech, language, and fluency.
A speech impairment is characterized by difficulty in articulation of words. Examples include stuttering or problems producing particular sounds. Articulation refers to the sounds, syllables, and phonology produced by the individual. Voice, however, may refer to the characteristics of the sounds produced—specifically, the pitch, quality, and intensity of the sound. Often, fluency will also be considered a category under speech, encompassing the characteristics of rhythm, rate, and emphasis of the sound produced.
A language impairment is a specific impairment in understanding and sharing thoughts and ideas, i.e. a disorder that involves the processing of linguistic information. Problems that may be experienced can involve the form of language, including grammar, morphology, syntax; and the functional aspects of language, including semantics and pragmatics.
An individual can have one or both types of impairment. These impairments/disorders are identified by a speech and language pathologist.
Speech disorders
The following are brief definitions of several of the more prominent speech disorders:
Apraxia of speech
Apraxia of speech is the acquired form of motor speech disorder caused by brain injury, stroke or dementia.
Developmental verbal dyspraxia
Developmental verbal dyspraxia refers specifically to a motor speech disorder. This is a neurological disorder. Individuals with developmental verbal apraxia encounter difficulty saying sounds, syllables, and words. The difficulties are not due to weakness of muscles, but rather on coordination between the brain and the specific parts of the body. Apraxia of speech is the acquired form of this disorder caused by brain injury, stroke or dementia.
Interventions are more effective when they occur individually at first, and between three and five times per week. With i
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https://en.wikipedia.org/wiki/Stripping%20reaction%20%28physics%29
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In nuclear physics, a stripping reaction is a nuclear reaction in which part of the incident nucleus combines with the target nucleus, and the remainder proceeds with most of its original momentum in almost its original direction. This reaction was first described by Stuart Thomas Butler in 1950. Deuteron stripping reactions have been extensively used to study nuclear reactions and structure, this occurs where the incident nucleus is a deuteron and only a proton emerges from the target nucleus. A simple one-step stripping reaction can be represented as
A+a →B+b
A + (b+x)a→(A+x)b+b
where A represents the target core, b represents the projectile core, and x is the transferred mass which may represent any number of particles.
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https://en.wikipedia.org/wiki/Negligible%20function
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For a similar term, please see negligible set. (disambiguation)
In mathematics, a negligible function is a function such that for every positive integer c there exists an integer Nc such that for all x > Nc,
Equivalently, we may also use the following definition.
A function is negligible, if for every positive polynomial poly(·) there exists an integer Npoly > 0 such that for all x > Npoly
History
The concept of negligibility can find its trace back to sound models of analysis. Though the concepts of "continuity" and "infinitesimal" became important in mathematics during Newton and Leibniz's time (1680s), they were not well-defined until the late 1810s. The first reasonably rigorous definition of continuity in mathematical analysis was due to Bernard Bolzano, who wrote in 1817 the modern definition of continuity. Later Cauchy, Weierstrass and Heine also defined as follows (with all numbers in the real number domain ):
(Continuous function) A function is continuous at if for every , there exists a positive number such that implies
This classic definition of continuity can be transformed into the
definition of negligibility in a few steps by changing parameters used in the definition. First, in the case with , we must define the concept of "infinitesimal function":
(Infinitesimal) A continuous function is infinitesimal (as goes to infinity) if for every there exists such that for all
Next, we replace by the functions where or by where is a positive polynomial. This leads to the definitions of negligible functions given at the top of this article. Since the constants can be expressed as with a constant polynomial, this shows that infinitesimal functions are a subset of negligible functions.
Use in cryptography
In complexity-based modern cryptography, a security scheme is
provably secure if the probability of security failure (e.g.,
inverting a one-way function, distinguishing cryptographically strong pseudorandom bits from truly random
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https://en.wikipedia.org/wiki/Zero-symmetric%20graph
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In the mathematical field of graph theory, a zero-symmetric graph is a connected graph in which each vertex has exactly three incident edges and, for each two vertices, there is a unique symmetry taking one vertex to the other. Such a graph is a vertex-transitive graph but cannot be an edge-transitive graph: the number of symmetries equals the number of vertices, too few to take every edge to every other edge.
The name for this class of graphs was coined by R. M. Foster in a 1966 letter to H. S. M. Coxeter. In the context of group theory, zero-symmetric graphs are also called graphical regular representations of their symmetry groups.
Examples
The smallest zero-symmetric graph is a nonplanar graph with 18 vertices. Its LCF notation is [5,−5]9.
Among planar graphs, the truncated cuboctahedral and truncated icosidodecahedral graphs are also zero-symmetric.
These examples are all bipartite graphs. However, there exist larger examples of zero-symmetric graphs that are not bipartite.
These examples also have three different symmetry classes (orbits) of edges. However, there exist zero-symmetric graphs with only two orbits of edges.
The smallest such graph has 20 vertices, with LCF notation [6,6,-6,-6]5.
Properties
Every finite zero-symmetric graph is a Cayley graph, a property that does not always hold for cubic vertex-transitive graphs more generally and that helps in the solution of combinatorial enumeration tasks concerning zero-symmetric graphs. There are 97687 zero-symmetric graphs on up to 1280 vertices. These graphs form 89% of the cubic Cayley graphs and 88% of all connected vertex-transitive cubic graphs on the same number of vertices.
All known finite connected zero-symmetric graphs contain a Hamiltonian cycle, but it is unknown whether every finite connected zero-symmetric graph is necessarily Hamiltonian. This is a special case of the Lovász conjecture that (with five known exceptions, none of which is zero-symmetric) every finite connected vertex-tr
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https://en.wikipedia.org/wiki/Q-Konhauser%20polynomials
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In mathematics, the q-Konhauser polynomials are a q-analog of the Konhauser polynomials, introduced by .
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https://en.wikipedia.org/wiki/Right%20border%20of%20heart
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The right border of the heart (right margin of heart) is a long border on the surface of the heart, and is formed by the right atrium.
The atrial portion is rounded and almost vertical; it is situated behind the third, fourth, and fifth right costal cartilages about 1.25 cm. from the margin of the sternum.
The ventricular portion, thin and sharp, is named the acute margin; it is nearly horizontal, and extends from the sternal end of the sixth right coastal cartilage to the apex of the heart.
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https://en.wikipedia.org/wiki/External%20fertilization
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External fertilization is a mode of reproduction in which a male organism's sperm fertilizes a female organism's egg outside of the female's body.
It is contrasted with internal fertilization, in which sperm are introduced via insemination and then combine with an egg inside the body of a female organism. External fertilization typically occurs in water or a moist area to facilitate the movement of sperm to the egg. The release of eggs and sperm into the water is known as spawning. In motile species, spawning females often travel to a suitable location to release their eggs.
However, sessile species are less able to move to spawning locations and must release gametes locally. Among vertebrates, external fertilization is most common in amphibians and fish. Invertebrates utilizing external fertilization are mostly benthic, sessile, or both, including animals such as coral, sea anemones, and tube-dwelling polychaetes. Benthic marine plants also use external fertilization to reproduce. Environmental factors and timing are key challenges to the success of external fertilization. While in the water, the male and female must both release gametes at similar times in order to fertilize the egg. Gametes spawned into the water may also be washed away, eaten, or damaged by external factors.
Sexual selection
Sexual selection may not seem to occur during external fertilization, but there are ways it actually can. The two types of external fertilizers are nest builders and broadcast spawners. For female nest builders, the main choice is the location of where to lay her eggs. A female can choose a nest close to the male she wants to fertilize her eggs, but there is no guarantee that the preferred male will fertilize any of the eggs. Broadcast spawners have a very weak selection, due to the randomness of releasing gametes. To look into the effect of female choice on external fertilization, an in vitro sperm competition experiment was performed. The results concluded that ther
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https://en.wikipedia.org/wiki/PicoChip
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Picochip was a venture-backed fabless semiconductor company based in Bath, England, founded in 2000. In January 2012 Picochip was acquired by Mindspeed Technologies, Inc and subsequently by Intel.
The company was active in two areas, with two distinct product families.
Picochip was one of the first companies to start developing solutions for small cell basestation (femtocells), for homes and offices. These help combat reception issues such as: dropped calls, poor sound quality, delays, and slow downloads. The idea is to increase the capacity of cellular networks and to address coverage holes.
Multi-core DSP
Picochip developed a multi-core digital signal processor, the picoArray. This integrates 250–300 individual DSP cores onto a single die (depending on the specific product) and as such it can be described as a Massively parallel processor array. Each of these cores is a 16-bit processor with Harvard architecture, local memory and 3-way VLIW. Although each device contained 250–300 processors, the architecture allowed devices to be connected to form far larger systems, in some cases with tens of thousands of cores.
The company had three multi-core DSP products (PC202 / 203 / 205) that delivered approximately 40 GMACS and 200 GIPS of performance. The earlier PC102 is obsolete.
The programming model allows each processor to be coded independently (in ANSI C or assembler) and then to communicate over an any:any interconnect mesh. The communication flows are fixed at compile time, not dynamically at run time (analogous to place & route of an FPGA but at higher level of abstraction). This can be described as communicating sequential processes. Each process maps to a processor, which is fully independent from other processors with "encapsulation", with interaction only through defined message passing and data flows through the mesh. This architecture is also related to object-oriented programming concepts. Notably, the development environment is deterministic: sim
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https://en.wikipedia.org/wiki/General-purpose%20modeling
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General-purpose modeling (GPM) is the systematic use of a general-purpose modeling language to represent the various facets of an object or a system. Examples of GPM languages are:
The Unified Modeling Language (UML), an industry standard for modeling software-intensive systems
EXPRESS, a data modeling language for product data, standardized as ISO 10303-11
IDEF, a group of languages from the 1970s that aimed to be neutral, generic and reusable
Gellish, an industry standard natural language oriented modeling language for storage and exchange of data and knowledge, published in 2005
XML, a data modeling language now beginning to be used to model code (MetaL, Microsoft .Net )
GPM languages are in contrast with domain-specific modeling languages (DSMs).
See also
Model-driven engineering (MDE)
Specification languages
Modeling languages
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https://en.wikipedia.org/wiki/Hermann%20Vermeil
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Hermann Vermeil (1889–1959) was a German mathematician who produced the first published proof that the scalar curvature is the only absolute invariant among those of prescribed type suitable for Albert Einstein’s theory. The theorem was proved by him in 1917 when he was Hermann Weyl's assistant.
Notes
External links
1889 births
1959 deaths
20th-century German mathematicians
Differential geometers
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https://en.wikipedia.org/wiki/ACSBG2
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Long-chain-fatty-acid—CoA ligase ACSBG2 is an enzyme that in humans is encoded by the ACSBG2 gene.
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https://en.wikipedia.org/wiki/Blade%20Network%20Technologies
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BLADE Network Technologies, based in Santa Clara, California, was a supplier of Ethernet network switches for blade servers and server and storage data center racks.
BLADE became part of IBM System Networking in 2010. Later sold to Lenovo as part of purchase of IBM x86 server division
History
On February 13, 2006, Garnett & Helfrich Capital
established BLADE Network Technologies, Inc., as a privately held company from a spin-out of Nortel's Blade Server Switch Unit, focused on networking for the blade server market.
Vikram Mehta was president and CEO.
In 2008, the company introduced its RackSwitch line of top-of-rack 1-10 Gigabit Ethernet data center switches. IBM acquired BLADE in October 2010.
Lenovo acquired IBM's server business, including BLADE in 2014.
See also
Fibre Channel over Ethernet
IBM BladeCenter
List of mergers and acquisitions by IBM
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https://en.wikipedia.org/wiki/Dave%20Needle
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David Lewis Needle (December 17, 1947 – February 20, 2016) was an American computer engineer. He was a key engineer and co-chief architect in the creation of the Amiga 1000 computer with Jay Miner, Dave Morse, and R. J. Mical. He was one of the main designers and developers of the custom chips of the Amiga computer. Later he co-invented the Atari Lynx and the 3DO Interactive Multiplayer with Morse and Mical.
A 1995 article in Next Generation commented: "It's true that of the machines that Mical and Needle have created, only the Amiga has been a true global mass market hit ... But it's only fair to put forward the argument that this is down to the marketing of the machines rather than the quality of the product."
Dave Needle died on February 20, 2016.
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https://en.wikipedia.org/wiki/Data%20deficient
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A data deficient (DD) species is one which has been categorized by the International Union for Conservation of Nature (IUCN) as offering insufficient information for a proper assessment of conservation status to be made. This does not necessarily indicate that the species has not been extensively studied; but it does indicate that little or no information is available on the abundance and distribution of the species.
The IUCN recommends that care be taken to avoid classing species as "data deficient" when the absence of records may indicate dangerously low abundance: "If the range of a taxon is suspected to be relatively circumscribed, if a considerable period of time has elapsed since the last record of the taxon, threatened status may well be justified" (see also precautionary principle).
See also
IUCN Red List data deficient species
List of data deficient amphibians
IUCN Red List data deficient species (Annelida)
List of data deficient arthropods
List of data deficient birds
IUCN Red List data deficient species (Cnidaria)
List of data deficient fishes
List of data deficient insects
List of data deficient invertebrates
List of data deficient mammals
List of data deficient molluscs
List of data deficient plants
List of data deficient reptiles
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https://en.wikipedia.org/wiki/Blocknots
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Blocknots were random sequences of numbers contained in a book and organized by numbered rows and columns and were used as additives in the reciphering of Soviet Union codes, during World War II. The Blocknot consisted of fifty sheets of 5-figure random additive, 100 additive groups to a sheet. No sheet was used more than once, thus the blocknots were in effect a form of one-time pad. The Soviet Unions highest grade ciphers that were used in the East, were the 5-figure codebook enciphered with the Blocknot book, and were generally considered unbreakable.
Technical Description
Blocknots were distributed centrally from an office in Moscow. Every Blocknot contained 5-figure groups in a number of sheets, for the enciphering of 5-figure messages. The encipherment was effected by applying additives taken from the pad, of which 50-100 5-figure groups appeared. Each pad had a 5-figure number and each sheet had a 2-figure number running consecutively. There were 5 different types of Blocknots, in two different categories
The Individual in which each table of random numbers was used only once.
The General in which each page of the Blocknot was valid for one day. The security of the additive sequence rested on the choice of different starting points for each message. In 5-figure messages, the blocknot was one of the first 10 Groups in the message. Its position changed at long intervals, but was always easy to re-identify. The Russians differentiated between three types of blocks:
The 3-block, DRIERBLOCK. I-block for Individual Block: 50 pages, additive read off in one direction only. The messages could be used and read only between 2 wireless telegraphy stations on one net.
The 6-block, SECHSERBLOCK. Z-block for Circular Block: 30 pages, additive read off in either direction. The messages could be used and read, between all W/T stations in a net.
The 2-block, ZWEIERBLOCK. OS-block. Used only in traffic from lower to higher formations.
Two other types were used, in lowe
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https://en.wikipedia.org/wiki/The%20Coroner%27s%20Toolkit
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The Coroner's Toolkit (or TCT) is a suite of free computer security programs by Dan Farmer and Wietse Venema for digital forensic analysis. The suite runs under several Unix-related operating systems: FreeBSD, OpenBSD, BSD/OS, SunOS/Solaris, Linux, and HP-UX. TCT is released under the terms of the IBM Public License.
Parts of TCT can be used to aid analysis of and data recovery from computer disasters.
TCT was superseded by The Sleuth Kit. Although TSK is only partially based on TCT, the authors of TCT have accepted it as official successor to TCT.
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https://en.wikipedia.org/wiki/Spell%20Catcher
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Spell Catcher, originally known as Thunder!, is a stand-alone spell checker for Atari ST, Macintosh and Microsoft Windows systems. It was published continually from 1985 until the untimely 2012 death of the primary developer, Evan Gross. Its original name refers to its lightning-fast speed, which set it apart from other spell checkers on the platform like Spellswell.
In addition to basic spell checking, later versions of the program offered a viewable dictionary and thesaurus, user-defined macro expansions, and auto-complete. Another notable feature was strong multilingual support, a rarity among such programs of the era. Over time, many of these features were also added to Mac OS X and Windows built-in spell checking functionality, but Spell Catcher remained in use due to its other features. It no longer runs under the most recent versions of macOS, which require 64-bit applications.
History
The program was originally released in 1985 for the Atari ST platform by Toronto-based Batteries Included, who sold it under the original name Thunder!. The designer of this version is listed as Mark Skapinker, but this name appears on no other documentation. There were two spell checkers with similar names at the same time, Turbo Lightning for DOS, and Mac Lightning for the Mac. Thunder also included statistics functions, including a word count and "grade level".
The Mac version was released a couple of months later. Batteries Included was purchased by Electronic Arts (EA) in 1987, as part of an AE buying spree. Thunder II was released in 1988, changing from a desk accessory to a control panel that hooked directly into the classic Mac OS text editing system to allow inline checking and replacement. During this period, the program won MacUser Eddy awards in 1986 and 1988.
In 1990, Gross was readying a version that ran under Apple's new System 7. EA had lost interest in the utilities market and sold the publishing rights to Baseline Publishing. The new Thunder 7 was release
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https://en.wikipedia.org/wiki/Farrell%E2%80%93Markushevich%20theorem
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In mathematics, the Farrell–Markushevich theorem, proved independently by O. J. Farrell (1899–1981) and A. I. Markushevich (1908–1979) in 1934, is a result concerning the approximation in mean square of holomorphic functions on a bounded open set in the complex plane by complex polynomials. It states that complex polynomials form a dense subspace of the Bergman space of a domain bounded by a simple closed Jordan curve. The Gram–Schmidt process can be used to construct an orthonormal basis in the Bergman space and hence an explicit form of the Bergman kernel, which in turn yields an explicit Riemann mapping function for the domain.
Proof
Let Ω be the bounded Jordan domain and let Ωn be bounded Jordan domains decreasing to Ω, with Ωn containing the closure of Ωn + 1. By the Riemann mapping theorem there is a conformal mapping fn of Ωn onto Ω, normalised to fix a given point in Ω with positive derivative there. By the Carathéodory kernel theorem fn(z) converges uniformly on compacta in Ω to z. In fact Carathéodory's theorem implies that the inverse maps tend uniformly on compacta to z. Given a subsequence of fn, it has a subsequence, convergent on compacta in Ω. Since the inverse functions converge to z, it follows that the subsequence converges to z on compacta. Hence fn converges to z on compacta in Ω.
As a consequence the derivative of fn tends to 1 uniformly on compacta.
Let g be a square integrable holomorphic function on Ω, i.e. an element of the Bergman space A2(Ω). Define gn on Ωn by gn(z) = g(fn(z))fn'(z). By change of variable
Let hn be the restriction of gn to Ω. Then the norm of hn is less than that of gn. Thus these norms are uniformly bounded. Passing to a subsequence if necessary, it can therefore be assumed that hn has a weak limit in A2(Ω). On the other hand, hn tends uniformly on compacta
to g. Since the evaluation maps are continuous linear functions on A2(Ω), g is the weak limit of hn. On the other hand, by Runge's theorem, hn lies in
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https://en.wikipedia.org/wiki/Inocybe
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Inocybe is a large genus of mushroom-forming fungi with over 1400 species, including all forms and variations. Members of Inocybe are mycorrhizal, and some evidence shows that the high degree of speciation in the genus is due to adaptation to different trees and perhaps even local environments.
Etymology
The name Inocybe means "fibrous hat". It is taken from the Greek words (in the genitive , meaning "muscle, nerve, fiber, strength, vigor") and ("head").
History
The genus was first described as Agaricus tribe Inocybe by Swedish scholar Elias Magnus Fries in volume 1 of his work, Systema mycologicum (1821), and verified in the volume 2 of his book Monographia Hymenomycetum Sueciae in 1863. All other renaming attempts are accepted synonymous.
Description
Typical mushrooms of the genus have various shades of brown, although some lilac or purplish species exist. Caps are small and conical, though flattening somewhat in age, generally with a pronounced central umbo. The cap often appears fibrous, giving the genus its common name of "fiber caps". Many species have a distinctive odor, various described as musty or spermatic.
Description valid for most species:
Pileus: small to medium size, thin, fleshy, initially narrow conical or bell-shaped, or with a prominent or flattened umbo in the center. It is not hygrophanous and has a dry appearance. The pileus margin often shows at first a pale curtain that disappears quickly, and in old age it often presents short radial cracks. The cuticle is finely silky and sometimes sprinkled with remnants of the partial veil, further developing radial fibers. There are also species with a woolly surface (woolly in mycological sense). Coloring is at first all white to gray-whitish varieties. Some retain color, others change, varying between ocher-yellowish and brown, various shapes, even lilac-like to purple.
Lamellae: are dense, thick and crowded, with short intermediate sinus at the edge and only weakly attached to the sti
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https://en.wikipedia.org/wiki/Urbach%20tail
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The Urbach tail is an exponential part in the energy spectrum of the absorption coefficient. This tail appears near the optical band edge in amorphous, disordered and crystalline materials.
History
Researchers began questioning the nature of "tail states" in disordered semiconductors in the 1950s. It was found that such tails arise from the strains sufficient to push local states past the band edges.
In 1953, the Austrian-American physicist Franz Urbach (1902–1969) found that such tails decay exponentially into the gap. Later, photoemission experiments delivered absorption models revealing temperature dependence of the tail.
A variety of amorphous crystalline solids expose exponential band edges via optical absorption. The universality of this feature suggested a common cause. Several attempts were made to explain the phenomenon, but these could not connect specific topological units to the electronic structure.
See also
Tauc plot
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https://en.wikipedia.org/wiki/Nexin
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Nexin is a proteinous inter-doublet linkage that prevents microtubules in the outer layer of axonemes from moving with respect to one another; otherwise, vesicular transport proteins such as dynein would dissolve the whole structure.
See also
Sorting nexin
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https://en.wikipedia.org/wiki/Arithmetic%20logic%20unit
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In computing, an arithmetic logic unit (ALU) is a combinational digital circuit that performs arithmetic and bitwise operations on integer binary numbers. This is in contrast to a floating-point unit (FPU), which operates on floating point numbers. It is a fundamental building block of many types of computing circuits, including the central processing unit (CPU) of computers, FPUs, and graphics processing units (GPUs).
The inputs to an ALU are the data to be operated on, called operands, and a code indicating the operation to be performed; the ALU's output is the result of the performed operation. In many designs, the ALU also has status inputs or outputs, or both, which convey information about a previous operation or the current operation, respectively, between the ALU and external status registers.
Signals
An ALU has a variety of input and output nets, which are the electrical conductors used to convey digital signals between the ALU and external circuitry. When an ALU is operating, external circuits apply signals to the ALU inputs and, in response, the ALU produces and conveys signals to external circuitry via its outputs.
Data
A basic ALU has three parallel data buses consisting of two input operands (A and B) and a result output (Y). Each data bus is a group of signals that conveys one binary integer number. Typically, the A, B and Y bus widths (the number of signals comprising each bus) are identical and match the native word size of the external circuitry (e.g., the encapsulating CPU or other processor).
Opcode
The opcode input is a parallel bus that conveys to the ALU an operation selection code, which is an enumerated value that specifies the desired arithmetic or logic operation to be performed by the ALU. The opcode size (its bus width) determines the maximum number of distinct operations the ALU can perform; for example, a four-bit opcode can specify up to sixteen different ALU operations. Generally, an ALU opcode is not the same as a machine langua
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https://en.wikipedia.org/wiki/Metric%20Structures%20for%20Riemannian%20and%20Non-Riemannian%20Spaces
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Metric Structures for Riemannian and Non-Riemannian Spaces is a book in geometry by Mikhail Gromov. It was originally published in French in 1981 under the title Structures métriques pour les variétés riemanniennes, by CEDIC (Paris).
History
The 1981 edition was edited by Jacques Lafontaine and Pierre Pansu. The English version, considerably expanded, was published in 1999 by Birkhäuser Verlag, with appendices by Pierre Pansu, Stephen Semmes, and Mikhail Katz. The book was well received and has been reprinted several times.
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https://en.wikipedia.org/wiki/Poset%20game
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In combinatorial game theory, poset games are mathematical games of strategy, generalizing many well-known games such as Nim and Chomp. In such games, two players start with a poset (a partially ordered set), and take turns choosing one point in the poset, removing it and all points that are greater. The player who is left with no point to choose, loses.
Game play
Given a partially ordered set (P, <), let
denote the poset formed by removing x from P.
A poset game on P, played between two players conventionally named Alice and Bob, is as follows:
Alice chooses a point x ∈ P; thus replacing P with Px, and then passes the turn to Bob who plays on Px, and passes the turn to Alice.
A player loses if it is his/her turn and there are no points to choose.
Examples
If P is a finite totally ordered set, then game play in P is exactly the same as the game play in a game of Nim with a heap of size |P|. For, in both games, it is possible to choose a move that leads to a game of the same type whose size is any number smaller than |P|. In the same way, a poset game with a disjoint union of total orders is equivalent to a game of Nim with multiple heaps with sizes equal to the chains in the poset.
A special case of Hackenbush, in which all edges are green (able to be cut by either player) and every configuration takes the form of a forest, may be expressed similarly, as a poset game on a poset in which, for every element x, there is at most one element y for which x covers y. If x covers y, then y is the parent of x in the forest on which the game is played.
Chomp may be expressed similarly, as a poset game on the product of total orders from which the infimum has been removed.
Grundy value
Poset games are impartial games, meaning that every move available to Alice would also be available to Bob if Alice were allowed to pass, and vice versa. Therefore, by the Sprague–Grundy theorem, every position in a poset game has a Grundy value, a number describing an equivalent posi
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https://en.wikipedia.org/wiki/Folded%20Reed%E2%80%93Solomon%20code
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In coding theory, folded Reed–Solomon codes are like Reed–Solomon codes, which are obtained by mapping Reed–Solomon codewords over a larger alphabet by careful bundling of codeword symbols.
Folded Reed–Solomon codes are also a special case of Parvaresh–Vardy codes.
Using optimal parameters one can decode with a rate of R, and achieve a decoding radius of 1 − R.
The term "folded Reed–Solomon codes" was coined in a paper by V.Y. Krachkovsky with an algorithm that presented Reed–Solomon codes with many random "phased burst" errors. The list-decoding algorithm for folded RS codes corrects beyond the bound for Reed–Solomon codes achieved by the Guruswami–Sudan algorithm for such phased burst errors.
History
One of the ongoing challenges in Coding Theory is to have error correcting codes achieve an optimal trade-off between (Coding) Rate and Error-Correction Radius. Though this may not be possible to achieve practically (due to Noisy Channel Coding Theory issues), quasi optimal tradeoffs can be achieved theoretically.
Prior to Folded Reed–Solomon codes being devised, the best Error-Correction Radius achieved was , by Reed–Solomon codes for all rates .
An improvement upon this bound was achieved by Parvaresh and Vardy for rates
For the Parvaresh–Vardy algorithm can decode a fraction of errors.
Folded Reed–Solomon Codes improve on these previous constructions, and can be list decoded in polynomial time for a fraction of errors for any constant .
Definition
Consider a Reed–Solomon code of length and dimension and a folding parameter . Assume that divides .
Mapping for Reed–Solomon codes like this:
where is a primitive element in
.
The folded version of Reed Solomon code , denoted is a code of block length over . are just Reed Solomon codes with consecutive symbols from RS codewords grouped together.
Graphic description
The above definition is made more clear by means of the diagram with , where is the folding parameter.
The message i
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https://en.wikipedia.org/wiki/Radiation%20detection
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The following Radiological protection instruments can be used to detect and measure ionizing radiation:
Ionization chambers
Gaseous ionization detectors
Geiger counters
Photodetectors
Scintillation counters
Semiconductor detectors
Radioactivity
Radiation protection
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https://en.wikipedia.org/wiki/Oocyte%20selection
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Oocyte selection is a procedure that is performed prior to in vitro fertilization, in order to use oocytes with maximal chances of resulting in pregnancy. In contrast, embryo selection takes place after fertilization.
Techniques
Chromosomal evaluation may be performed. Embryos from rescued in vitro-matured metaphase II (IVM-MII) oocytes show significantly higher fertilization rates and more blastomeres per embryo compared with those from arrested metaphase I (MI) oocytes (58.5% vs. 43.9% and 5.7 vs. 5.0, respectively).
Also, morphological features of the oocyte that can be obtained by standard light or polarized light microscopy. However, there is no clear tendency in recent publications to a general increase in predictive value of morphological features. Suggested techniques include zona pellucida imaging, which can detect differences in birefringence between eggs, which is a predictor of compaction, blastulation and pregnancy.
Potentially, polar body biopsy may be used for molecular analysis, and can be used for preimplantation genetic screening.
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https://en.wikipedia.org/wiki/Berkeley%20IRAM%20project
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The Berkeley IRAM project was a 1996–2004 research project in the Computer Science Division of the University of California, Berkeley which explored computer architecture enabled by the wide bandwidth between memory and processor made possible when both are designed on the same integrated circuit (chip). Since it was envisioned that such a chip would consist primarily of random-access memory (RAM), with a smaller part needed for the central processing unit (CPU), the research team used the term "Intelligent RAM" (or IRAM) to describe a chip with this architecture. Like the J–Machine project at MIT, the primary objective of the research was to avoid the Von Neumann bottleneck which occurs when the connection between memory and CPU is a relatively narrow memory bus between separate integrated circuits.
Theory
With strong competitive pressures, the technology employed for each component of a computer system—principally CPU, memory, and offline storage—is typically selected to minimize the cost needed to attain a given level of performance. Though both microprocessor and memory are implemented as integrated circuits, the prevailing technology used for each differs; microprocessor technology optimizes speed and memory technology optimizes density. For this reason, the integration of memory and processor in the same chip has (for the most part) been limited to static random-access memory (SRAM), which may be implemented using circuit technology optimized for logic performance, rather than the denser and lower-cost dynamic random-access memory (DRAM), which is not. Microprocessor access to off-chip memory costs time and power, however, significantly limiting processor performance. For this reason computer architecture employing a hierarchy of memory systems has developed, in which static memory is integrated with the microprocessor for temporary, easily accessible storage (or cache) of data which is also retained off-chip in DRAM. Since the on-chip cache memory is redun
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https://en.wikipedia.org/wiki/Optimal%20stopping
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In mathematics, the theory of optimal stopping or early stopping is concerned with the problem of choosing a time to take a particular action, in order to maximise an expected reward or minimise an expected cost. Optimal stopping problems can be found in areas of statistics, economics, and mathematical finance (related to the pricing of American options). A key example of an optimal stopping problem is the secretary problem. Optimal stopping problems can often be written in the form of a Bellman equation, and are therefore often solved using dynamic programming.
Definition
Discrete time case
Stopping rule problems are associated with two objects:
A sequence of random variables , whose joint distribution is something assumed to be known
A sequence of 'reward' functions which depend on the observed values of the random variables in 1:
Given those objects, the problem is as follows:
You are observing the sequence of random variables, and at each step , you can choose to either stop observing or continue
If you stop observing at step , you will receive reward
You want to choose a stopping rule to maximize your expected reward (or equivalently, minimize your expected loss)
Continuous time case
Consider a gain process defined on a filtered probability space and assume that is adapted to the filtration. The optimal stopping problem is to find the stopping time which maximizes the expected gain
where is called the value function. Here can take value .
A more specific formulation is as follows. We consider an adapted strong Markov process defined on a filtered probability space where denotes the probability measure where the stochastic process starts at . Given continuous functions , and , the optimal stopping problem is
This is sometimes called the MLS (which stand for Mayer, Lagrange, and supremum, respectively) formulation.
Solution methods
There are generally two approaches to solving optimal stopping problems. When the underlying process
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https://en.wikipedia.org/wiki/Orion%27s%20Arm
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Orion's Arm (also called the Orion's Arm Universe Project, OAUP, or simply OA and formerly known as the Orion's Arm Worldbuilding Group) is a multi-authored online science fiction world-building project, first established in 2000 by M. Alan Kazlev, Donna Malcolm Hirsekorn, Bernd Helfert and Anders Sandberg and further co-authored by many people since. Anyone can contribute articles, stories, artwork, or music to the website. A large mailing list exists, in which members debate aspects of the world they are creating, discussing additions, modifications, issues arising, and work to be done.
A computer game and a tabletop role-playing game are being developed by the community, within the OA milieu. There is an ezine for Orion's Arm fiction, art, and commentary, called Voices: Future Tense, add-ons for the Celestia program to displaying Orion's Arm planets, spacecraft and other objects, and additional transhumanist flavored SF illustrations.
The first published Orion's Arm book, a collection of five novellas set within the OA universe, called Against a Diamond Sky, was released in September 2009 by Outskirts Press.
The second published Orion's Arm book, called After Tranquility, was released in February 2014.
Setting
The fictional history of the OA setting spans over 10,000 years, beginning with the real-world present day; dates in OA are marked according to the Tranquility Calendar (which is named after Tranquility Base and started after the Apollo 11 landing). OA claims to adhere to plausible, or "hard" science fiction; that is, there are no human-like aliens, no literal faster-than-light travel or other violations of the known laws of physics, and no "naval analogy" space battles. Certain speculative technologies, such as the creation of "negative mass" (averaged null energy condition-violating) exotic matter and the manipulation of strange forms of matter, such as magnetic monopoles and Q-balls, on length scales much smaller than that of an atom, strong artific
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https://en.wikipedia.org/wiki/Applied%20element%20method
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The applied element method (AEM) is a numerical analysis used in predicting the continuum and discrete behavior of structures. The modeling method in AEM adopts the concept of discrete cracking allowing it to automatically track structural collapse behavior passing through all stages of loading: elastic, crack initiation and propagation in tension-weak materials, reinforcement yield, element separation, element contact and collision, as well as collision with the ground and adjacent structures.
History
Exploration of the approach employed in the applied element method began in 1995 at the University of Tokyo as part of Dr. Hatem Tagel-Din's research studies. The term "applied element method" itself, however, was first coined in 2000 in a paper called "Applied element method for structural analysis: Theory and application for linear materials". Since then AEM has been the subject of research by a number of academic institutions and the driving factor in real-world applications. Research has verified its accuracy for: elastic analysis; crack initiation and propagation; estimation of failure loads at reinforced concrete structures; reinforced concrete structures under cyclic loading; buckling and post-buckling behavior; nonlinear dynamic analysis of structures subjected to severe earthquakes; fault-rupture propagation; nonlinear behavior of brick structures; and the analysis of glass reinforced polymers (GFRP) walls under blast loads.
Technical discussion
In AEM, the structure is divided virtually and modeled as an assemblage of relatively small elements. The elements are then connected through a set of normal and shear springs located at contact points distributed along with the element faces. Normal and shear springs are responsible for the transfer of normal and shear stresses from one element to the next.
Element generation and formulation
The modeling of objects in AEM is very similar to modeling objects in FEM. Each object is divided into a series of eleme
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https://en.wikipedia.org/wiki/Navini%20Networks
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Navini Networks was a company that developed an Internet access system based on WiMAX wireless communication standards. This access system was subsequently acquired by Cisco Systems in October, 2007.
Company
In January 2000, Wu-Fu Chen and Guanghan Xu formed Navini Networks and developed a wireless Internet access system.
The company was based in Richardson, Texas and was privately funded by several investment-funds.
In 2001 it was awarded the 'Start-Up of the Year' award by KPMG and in 2002 it won some national and regional prizes.
Between the formation and early 2003 it attracted $66.5 million from private investors and employed 130 employees.
When it was sold in October 2007 for $330 million to Cisco Systems, Navini had 70 customers.
A Navini customer would be an Internet service provider providing wireless Internet access, mainly in areas where there are only limited wired alternatives available (such as Docsis access via a cable-TV network or DSL via the telephone network).
Products
Navini developed a WiMAX wireless internet-access infrastructure consisting of two main parts: the central headend system with the special antennas and the RipWave modems or customer premises equipment
The Navini products offered a non line-of-sight wireless access system. The popular Wi-Fi systems require an unobstructed view between the antenna of the transmitter and the receiver for a good reception of the signals: when the view is obstructed the signal strength decreases and the reach of the signal is very small.
By using a technique called spot beaming, normally used in satellite communications, it was possible to use radio-signals on frequencies that would normally require an unobstructed path between the transmitter and receiver or high-power transmitters.
A Navini system consists of one management-system, one or more base-systems and the user-modems or customer premises equipment.
Ripwave EMS
At the heart of a Navini-based internet access system is the EMS or Element
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https://en.wikipedia.org/wiki/The%20Institute%20for%20Cultural%20Research
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The Institute for Cultural Research (ICR) was a London-based, UK-registered educational charity, events organizer and publisher which aimed to stimulate study, debate, education and research into all aspects of human thought, behaviour and culture. It brought together many distinguished speakers, writers and Fellows over the years.
A statement issued in 2013 by the institute on its official web site read: "As of summer 2013, the Institute has suspended its activities following the formation of a new charity, The Idries Shah Foundation."
History
The institute was founded in 1965 by the well-known writer, thinker and Sufi teacher Idries Shah to facilitate the dissemination of ideas, information and understanding between cultures. Its Objects and Regulations were officially first adopted on 21 January 1966.
In his book Listening to Idries Shah, author, psychotherapist and tutor, Ivan Tyrrell recounts a conversation in which Shah explained his reasons for founding the ICR: "I want to attract ordinary people and help them think about psychological and cultural issues. But, as an individual, I can't easily get people to listen seriously. I discovered, however, that if I call myself an 'institute' – they will," Shah told him. Tyrrell adds: "I heard [Shah] say many times over the years, 'We live in an appearance culture' [...] That is one reason why it was necessary for him to create ICR: people like to join an organisation and be part of a community."
Based for some time at Tunbridge Wells in Kent, the institute was later based in London. Shah acted as the Institute's Director of Studies whilst still alive. Nobel Prize-winning novelist Doris Lessing, who was influenced by Idries Shah, has also contributed to the Institute.
Aims and remit
The Institute's stated aim was "to stimulate study, debate, education and research into all aspects of human thought, behaviour and culture" and to make the results of its members' academic work accessible to society and also to acade
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https://en.wikipedia.org/wiki/Divergence%20theorem
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In vector calculus, the divergence theorem, also known as Gauss's theorem or Ostrogradsky's theorem, is a theorem which relates the flux of a vector field through a closed surface to the divergence of the field in the volume enclosed.
More precisely, the divergence theorem states that the surface integral of a vector field over a closed surface, which is called the "flux" through the surface, is equal to the volume integral of the divergence over the region inside the surface. Intuitively, it states that "the sum of all sources of the field in a region (with sinks regarded as negative sources) gives the net flux out of the region".
The divergence theorem is an important result for the mathematics of physics and engineering, particularly in electrostatics and fluid dynamics. In these fields, it is usually applied in three dimensions. However, it generalizes to any number of dimensions. In one dimension, it is equivalent to integration by parts. In two dimensions, it is equivalent to Green's theorem.
Explanation using liquid flow
Vector fields are often illustrated using the example of the velocity field of a fluid, such as a gas or liquid. A moving liquid has a velocity—a speed and a direction—at each point, which can be represented by a vector, so that the velocity of the liquid at any moment forms a vector field. Consider an imaginary closed surface S inside a body of liquid, enclosing a volume of liquid. The flux of liquid out of the volume at any time is equal to the volume rate of fluid crossing this surface, i.e., the surface integral of the velocity over the surface.
Since liquids are incompressible, the amount of liquid inside a closed volume is constant; if there are no sources or sinks inside the volume then the flux of liquid out of S is zero. If the liquid is moving, it may flow into the volume at some points on the surface S and out of the volume at other points, but the amounts flowing in and out at any moment are equal, so the net flux of liqui
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https://en.wikipedia.org/wiki/Convex%20layers
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In computational geometry, the convex layers of a set of points in the Euclidean plane are a sequence of nested convex polygons having the points as their vertices. The outermost one is the convex hull of the points and the rest are formed in the same way recursively. The innermost layer may be degenerate, consisting only of one or two points.
The problem of constructing convex layers has also been called onion peeling or onion decomposition.
Although constructing the convex layers by repeatedly finding convex hulls would be slower, it is possible to partition any set of points into its convex layers in time .
An early application of the convex layers was in robust statistics, as a way of identifying outliers and measuring the central tendency of a set of sample points. In this context, the number of convex layers surrounding a given point is called its convex hull peeling depth, and the convex layers themselves are the depth contours for this notion of data depth.
Convex layers may be used as part of an efficient range reporting data structure for listing all of the points in a query half-plane. The points in the half-plane from each successive layer may be found by a binary search to find the most extreme point in the direction of the half-plane, and then searching sequentially from there. Fractional cascading can be used to speed up the binary searches, giving total query time to find points out of a set of .
The points of an grid have convex layers, as do the same number of uniformly random points within any convex shape.
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https://en.wikipedia.org/wiki/Zearalanone
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Zearalanone (ZAN) is a mycoestrogen that is a derivative of zearalenone (ZEN). Zearalanone can be extracted from medical herbs and edible herbs along with aflatoxins in the same time by a specific immunoaffinity column.
See also
α-Zearalenol
β-Zearalenol
Taleranol
Zeranol
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https://en.wikipedia.org/wiki/Descartes%27%20Error
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Descartes' Error: Emotion, Reason, and the Human Brain is a 1994 book by neuroscientist António Damásio describing the physiology of rational thought and decision, and how the faculties could have evolved through Darwinian natural selection. Damásio refers to René Descartes' separation of the mind from the body (the mind/body dualism) as an error because reasoning requires the guidance of emotions and feelings conveyed from the body. Written for the layperson, Damásio uses the dramatic 1868 railroad accident case of Phineas Gage as a reference for incorporating data from multiple modern clinical cases, enumerating damaging cognitive effects when feelings and reasoning become anatomically decoupled. The book provides an analysis of diverse clinical data contrasting a wide range of emotional changes following frontal lobe damage as well as lower (medulla) and anterior areas of the brain such as the anterior cingulate. Among his experimental evidence and testable hypotheses, Damásio presents the "somatic marker hypothesis", a proposed mechanism by which emotions guide (or bias) behavior and decision-making, and positing that rationality requires emotional input. He argues that René Descartes' "error" was the dualist separation of mind and body, rationality and emotion.
Publication data
Harper Perennial, 1995 paperback:
Penguin, 2005 paperback reprint:
See also
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https://en.wikipedia.org/wiki/Atlas%20Consortium
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The Atlas Consortium (stylized as 'ATLAS') comprises four partner companies; DXC Technology, Fujitsu, Airbus Defence and Space and CGI. Each Atlas partner has extensive experience of major technology implementation programmes in both the public and private sectors. Some 3,000 IT professionals have worked on the development and delivery of the ATLAS programme.
The consortium is tasked with developing Defence Information Infrastructure (DII) which is a secure military network for the MoD (United Kingdom's Ministry of Defence). This is the largest, most complex information infrastructure rolled out in Europe and connects 300,000 users and 150,000 terminals in 2,000 MoD locations around the world. DII provides a range of software enabling collaborative working across geographical and organisational boundaries and hosts several hundred MoD applications from a range of suppliers, all designed to meet exacting security standards.
It provides connectivity from ‘business space to battlespace’ in MoD offices in the UK, bases overseas or deployed at sea or on the front line. This demands a high level of resilience, flexibility and security.
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https://en.wikipedia.org/wiki/Localized%20molecular%20orbitals
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Localized molecular orbitals are molecular orbitals which are concentrated in a limited spatial region of a molecule, such as a specific bond or lone pair on a specific atom. They can be used to relate molecular orbital calculations to simple bonding theories, and also to speed up post-Hartree–Fock electronic structure calculations by taking advantage of the local nature of electron correlation. Localized orbitals in systems with periodic boundary conditions are known as Wannier functions.
Standard ab initio quantum chemistry methods lead to delocalized orbitals that, in general, extend over an entire molecule and have the symmetry of the molecule. Localized orbitals may then be found as linear combinations of the delocalized orbitals, given by an appropriate unitary transformation.
In the water molecule for example, ab initio calculations show bonding character primarily in two molecular orbitals, each with electron density equally distributed among the two O-H bonds. The localized orbital corresponding to one O-H bond is the sum of these two delocalized orbitals, and the localized orbital for the other O-H bond is their difference; as per Valence bond theory.
For multiple bonds and lone pairs, different localization procedures give different orbitals. The Boys and Edmiston-Ruedenberg localization methods mix these orbitals to give equivalent bent bonds in ethylene and rabbit ear lone pairs in water, while the Pipek-Mezey method preserves their respective σ and π symmetry.
Equivalence of localized and delocalized orbital descriptions
For molecules with a closed electron shell, in which each molecular orbital is doubly occupied, the localized and delocalized orbital descriptions are in fact equivalent and represent the same physical state. It might seem, again using the example of water, that placing two electrons in the first bond and two other electrons in the second bond is not the same as having four electrons free to move over both bonds. However, in quantu
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https://en.wikipedia.org/wiki/Siming%20%28deity%29
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Siming () refers to a Chinese deity or deified functionary of that title who makes fine adjustments to human fate, with various English translations (such as, the Master of Fate, Controller of Fate, Deified Judge of Life, Arbiter of Fate, Director of Allotted Life Spans, and Director of Destinies). Siming is both an abstract deity (or title thereof) and a celestial asterism.
Siming, as Director of Destinies, has the bureaucratic function of human lifespan allocation. Siming seems to have roots in the shamanic traditions, then later to have somewhat assimilated with the Kitchen God, as in the Daoist case of the Three Worms, in which Siming becomes a deity to whom home household activities are periodically reported,
As an asterism, or apparent stellar constellation, Siming is associated with the Wenchang Wang star pattern, near the Big Dipper, in what is more or less Aquarius.
Sometimes the term Siming is qualified by (da, meaning "big" or "greater") or by (shao, meaning "small" or "lesser").
Siming (deity)
The Siming deity has the bureaucratic function of human lifespan allocation. In bureaucratic terms, Si (司) is a common term, meaning "in charge of", "a person or department which is in charge of something", often translated as "secretary". Commonly, in real life or in imagined bureaucracies, there were Chief and Assistant Secretaries (Dasi and Shaosi). Ming (命) is a complicated word with a long folk and technical history, basically meaning "life" or "the balance of fate or destiny", personified as Siming. Often, a deified entity such as Siming receives increased sanctity over time, signified by additional official titles.
Powers and duties
As a deity Siming takes his, her, or their place in a complex cosmological system of Chinese religion and mythology. Over time, this system became a visualization of a complex cosmology including the elaboration of a heavenly bureaucracy, somewhat parallel to the earthly bureaucracy of the Chinese state, and invoking the
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https://en.wikipedia.org/wiki/Marc%20Tremblay
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Marc Tremblay is a distinguished engineer at Microsoft. Prior to joining Microsoft in April 2009, he was senior vice president and chief technology officer of the microelectronics business unit at Sun Microsystems. He was instrumental in the design of various microprocessors at Sun, including the UltraSPARC, UltraSPARC II, MAJC, UltraSPARC T1, and the cancelled Rock processor. In the process, he was awarded more patents than any other Sun employee.
Career
Tremblay worked at Sun Microsystems for 18 years. In 2009, he joined Microsoft's strategic software/silicon architecture group, led by chief research and strategy officer, Craig Mundie. A team worked under Tremblay developing software semiconductor technologies. The group, known as SiArch, works on green, adaptive and parallel computing.
Education
He received his bachelor's degree from Laval University in Canada, and both his M.S. (1985) and Ph.D. (1991) degrees from UCLA.
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https://en.wikipedia.org/wiki/Enterococcus%20gallinarum
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Enterococcus gallinarum is a species of Enterococcus. E. gallinarum demonstrates an inherent, low-level resistance to vancomycin. Resistance is due to a chromosomal gene, vanC, which encodes for a terminal D-alanine-D-serine instead of the usual D-alanine-D-alanine in cell wall peptidoglycan precursor proteins. That is a separate mechanism than the vancomycin resistance seen in VRE isolates of E. faecium and E. faecalis which is mediated by vanA or vanB. This species is known to cause clusters of infection, although it considered very rare. It is the only other known enterococcal species besides E. faecium and E. faecalis known to cause outbreaks and spread in hospitals.
A study published in 2018 found that this infectious gut bacterium can translocate (spread) to other organs such as the lymph nodes, liver, and spleen, triggering an autoimmune reaction in humans and mice. E. gallinarum was found during three liver biopsies of individuals with systemic lupus erythematosus and autoimmune liver disease. The autoimmune reaction was found to be suppressed when an intramuscular vaccine or antibiotic was administered.
The bacterium can also cause meningitis, although rare and sepsis.
The antibiotics linezolid, daptomycin and gentamicin, levofloxacin, and penicillin G are effective against the bacteria, depending on the specific isolate.
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https://en.wikipedia.org/wiki/Second%20metatarsal%20bone
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The second metatarsal bone is a long bone in the foot. It is the longest of the metatarsal bones, being prolonged backward and held firmly into the recess formed by the three cuneiform bones. The second metatarsal forms joints with the second proximal phalanx (a bone in the second toe) through the metatarsophalangeal joint, the cuneiform bones, third metatarsal and occasionally the first metatarsal bone.
Structure
Like the four other metatarsal bones, it can be divided into three parts: base, body and head. The base is the part closest to the ankle and the head is closest to the big toe. The narrowed part in the middle is referred to as the body of the bone. The bone is somewhat flattened, giving it two sides: the plantar (towards the sole of the foot) and the dorsal side (the area facing upwards while standing).
Its base is broad above, narrow and rough below.
It presents four articular surfaces: one behind, of a triangular form, for articulation with the intermediate cuneiform bone; one at the upper part of its medial surface, for articulation with the medial cuneiform; and two on its lateral surface, an upper and lower, separated by a rough non-articular interval. Each of these lateral articular surfaces is divided into two by a vertical ridge: the two anterior facets articulate with the third metatarsal and the two posterior (sometimes continuous) with the lateral cuneiform. A fifth facet is occasionally present for articulation with the first metatarsal; it is oval in shape, and is situated on the medial side of the body near the base.
The second metatarsal base acts as a "keystone" (like in an arch) for the lisfranc joint.
Muscle attachments
The first and second dorsal interossei muscles attach to the second metatarsal bone, the first dorsal interosseus from the medial side of the bone and the second dorsal interosseus from the lateral side. The function of the muscle is to spread the toes.
The horizontal head of the adductor hallucis also originates
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https://en.wikipedia.org/wiki/Strobilus
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A strobilus (: strobili) is a structure present on many land plant species consisting of sporangia-bearing structures densely aggregated along a stem. Strobili are often called cones, but some botanists restrict the use of the term cone to the woody seed strobili of conifers. Strobili are characterized by a central axis (anatomically a stem) surrounded by spirally arranged or decussate structures that may be modified leaves or modified stems.
Leaves that bear sporangia are called sporophylls, while sporangia-bearing stems are called sporangiophores.
Lycophytes
Some members of both of the two modern classes of Lycopodiophyta (Lycopodiopsida and Isoetopsida) produce strobili. In all cases, the lateral organs of the strobilus are microphylls, bearing sporangia. In other lycophytes, ordinary foliage leaves can act as sporophylls, and there are no organized strobili.
Sphenophytes
The single extant genus of Equisetophyta, Equisetum, produces strobili in which the lateral organs are sporangiophores. Developmental evidence and comparison with fossil members of the group show that the sporangiophores are reduced stems, rather than leaves. Sporangia are terminal.
Seed plants
With the exception of flowering plants, seed plants produce ovules and pollen in different structures. Strobili bearing microsporangia are called microsporangiate strobili or pollen cones, and those bearing ovules are megasporangiate strobili or seed cones (or ovulate cones).
Cycads
Cycadophyta are typically dioecious (seed strobili and pollen strobili are produced on separate plants). The lateral organs of seed strobili are megasporophylls (modified leaves) that bear two to several marginal ovules. Pollen strobili consist of microsporophylls, each of which may have dozens or hundreds of abaxial microsporangia.
Ginkgos
The single living member of the Ginkgophyta, Ginkgo biloba produces pollen strobili, but the ovules are typically borne in pairs at the end of a stem, not in a strobilus. When there a
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https://en.wikipedia.org/wiki/D-Wave%20Systems
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D-Wave Quantum Systems Inc. is a Canadian quantum computing company, based in Burnaby, British Columbia. D-Wave was the world's first company to sell computers to exploit quantum effects in their operation. D-Wave's early customers include Lockheed Martin, University of Southern California, Google/NASA and Los Alamos National Lab.
In 2015, D-Wave's 2X Quantum Computer with more than 1,000 qubits was installed at the Quantum Artificial Intelligence Lab at NASA Ames Research Center. They have subsequently shipped systems with 2,048 qubits. In 2019, D-Wave announced a 5000-qubit system available mid-2020, using their new Pegasus chip with 15 connections per qubit. D-Wave does not implement a generic quantum computer; instead, their computers implement specialized quantum annealing. However, D-Wave announced plans in 2021 that they will work on universal gate-base quantum computers as well in the future.
History
D-Wave was founded by Haig Farris (former chair of board), Geordie Rose (former CEO/CTO), Bob Wiens (former CFO), and Alexandre Zagoskin (former VP Research and Chief Scientist). Farris taught a business course at the University of British Columbia (UBC), where Rose obtained his PhD, and Zagoskin was a postdoctoral fellow. The company name refers to their first qubit designs, which used d-wave superconductors.
D-Wave operated as an offshoot from UBC, while maintaining ties with the Department of Physics and Astronomy. It funded academic research in quantum computing, thus building a collaborative network of research scientists. The company collaborated with several universities and institutions, including UBC, IPHT Jena, Université de Sherbrooke, University of Toronto, University of Twente, Chalmers University of Technology, University of Erlangen, and Jet Propulsion Laboratory. These partnerships were listed on D-Wave's website until 2005. In June 2014, D-Wave announced a new quantum applications ecosystem with computational finance firm 1QB Information Te
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https://en.wikipedia.org/wiki/HIV%20drug%20resistance
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HIV drug resistance occurs when microevolution causes virions to become tolerant to antiretroviral treatments (ART). ART can be used to successfully manage HIV infection, but a number of factors can contribute to the virus mutating and becoming resistant. Drug resistance occurs as bacterial or viral populations evolve to no longer respond to medications that previously worked. In the case of HIV, there have been recognized cases of treatment resistant strains since 1989, with drug resistance being a major contributor to treatment failure. While global incidence varies greatly from region to region, there has been a general increase in overall HIV drug resistance. The two main types of resistance, primary and induced, differ mostly in causation, with the biggest cause of resistance being a lack of adherence to the specific details of treatment. These newly created resistant strains of HIV pose a public health issue as they infect a growing number of people because they are harder to treat, and can be spread to other individuals. For this reason, the reaction to the growing number of cases of resistant HIV strains has mostly been to try to increase access to treatment and implement other measures to make sure people stay in care, as well as to look into the development of an HIV vaccine or cure.
Mechanisms of resistance
HIV is considered resistant when it no longer respond to known treatments. Because currently there is no known cure for HIV, the goal of treatment is to reduce an infected individual's viral load to the point where it is no longer detectable in order to alleviate their symptoms and reduce their risk of infecting others. HIV drug resistance poses an issue because it reduces the possible HIV medications a person can take due to cross resistance. In cross resistance, an entire class of medication is considered ineffective in lowering a patient's HIV viral load because all the drugs in a given class share the same mechanism of action. Therefore, developm
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https://en.wikipedia.org/wiki/Time-weighted%20average%20price
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In finance, time-weighted average price (TWAP) is the average price of a security over a specified time.
TWAP is also sometimes used to describe a TWAP card, that is a strategy that will attempt to execute an order and achieve the TWAP or better. A TWAP strategy underpins more sophisticated ways of buying and selling than simply executing orders en masse: for example, dumping a huge number of shares in one block is likely to affect market perceptions, with an adverse effect on the price.
Use
A TWAP strategy is often used to minimize a large order's impact on the market and result in price improvement. High-volume traders use TWAP to execute their orders over a specific time, so they trade to keep the price close to that which reflects the true market price. TWAP orders are a strategy of executing trades evenly over a specified time period. Volume-weighted average price (VWAP) balances execution with volume. Regularly, a VWAP trade will buy or sell 40% of a trade in the first half of the day and then the other 60% in the second half of the day. A TWAP trade would most likely execute an even 50/50 volume in the first and second half of the day.
Formula
TWAP is calculated using the following formula:
where:
is Time Weighted Average Price;
is the price of security at a time of measurement;
is change of time since previous price measurement;
is each individual measurement that takes place over the defined period of time.
Increased period of measurements results in a less up-to-date price.
See also
Volume-weighted average price
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https://en.wikipedia.org/wiki/Landscape%20ecology
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Landscape ecology is the science of studying and improving relationships between ecological processes in the environment and particular ecosystems. This is done within a variety of landscape scales, development spatial patterns, and organizational levels of research and policy. Concisely, landscape ecology can be described as the science of "landscape diversity" as the synergetic result of biodiversity and geodiversity.
As a highly interdisciplinary field in systems science, landscape ecology integrates biophysical and analytical approaches with humanistic and holistic perspectives across the natural sciences and social sciences. Landscapes are spatially heterogeneous geographic areas characterized by diverse interacting patches or ecosystems, ranging from relatively natural terrestrial and aquatic systems such as forests, grasslands, and lakes to human-dominated environments including agricultural and urban settings.
The most salient characteristics of landscape ecology are its emphasis on the relationship among pattern, process and scales, and its focus on broad-scale ecological and environmental issues. These necessitate the coupling between biophysical and socioeconomic sciences. Key research topics in landscape ecology include ecological flows in landscape mosaics, land use and land cover change, scaling, relating landscape pattern analysis with ecological processes, and landscape conservation and sustainability. Landscape ecology also studies the role of human impacts on landscape diversity in the development and spreading of new human pathogens that could trigger epidemics.
Terminology
The German term – thus landscape ecology – was coined by German geographer Carl Troll in 1939. He developed this terminology and many early concepts of landscape ecology as part of his early work, which consisted of applying aerial photograph interpretation to studies of interactions between environment and vegetation.
Explanation
Heterogeneity is the measure of how p
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