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https://en.wikipedia.org/wiki/Magnetosome
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Magnetosomes are membranous structures present in magnetotactic bacteria (MTB). They contain iron-rich magnetic particles that are enclosed within a lipid bilayer membrane. Each magnetosome can often contain 15 to 20 magnetite crystals that form a chain which acts like a compass needle to orient magnetotactic bacteria in geomagnetic fields, thereby simplifying their search for their preferred microaerophilic environments. Recent research has shown that magnetosomes are invaginations of the inner membrane and not freestanding vesicles. Magnetite-bearing magnetosomes have also been found in eukaryotic magnetotactic algae, with each cell containing several thousand crystals.
Overall, magnetosome crystals have high chemical purity, narrow size ranges, species-specific crystal morphologies and exhibit specific arrangements within the cell. These features indicate that the formation of magnetosomes is under precise biological control and is mediated biomineralization.
Magnetotactic bacteria usually mineralize either iron oxide magnetosomes, which contain crystals of magnetite (), or iron sulfide magnetosomes, which contain crystals of greigite (). Several other iron sulfide minerals have also been identified in iron sulfide magnetosomes—including mackinawite (tetragonal FeS) and a cubic FeS—which are thought to be precursors of . One type of magnetotactic bacterium present at the oxic-anoxic transition zone (OATZ) of the southern basin of the Pettaquamscutt River Estuary, Narraga
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https://en.wikipedia.org/wiki/Ribosomal%20RNA
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Ribosomal ribonucleic acid (rRNA) is a type of non-coding RNA which is the primary component of ribosomes, essential to all cells. rRNA is a ribozyme which carries out protein synthesis in ribosomes. Ribosomal RNA is transcribed from ribosomal DNA (rDNA) and then bound to ribosomal proteins to form small and large ribosome subunits. rRNA is the physical and mechanical factor of the ribosome that forces transfer RNA (tRNA) and messenger RNA (mRNA) to process and translate the latter into proteins. Ribosomal RNA is the predominant form of RNA found in most cells; it makes up about 80% of cellular RNA despite never being translated into proteins itself. Ribosomes are composed of approximately 60% rRNA and 40% ribosomal proteins by mass.
Structure
Although the primary structure of rRNA sequences can vary across organisms, base-pairing within these sequences commonly forms stem-loop configurations. The length and position of these rRNA stem-loops allow them to create three-dimensional rRNA structures that are similar across species. Because of these configurations, rRNA can form tight and specific interactions with ribosomal proteins to form ribosomal subunits. These ribosomal proteins contain basic residues (as opposed to acidic residues) and aromatic residues (i.e. phenylalanine, tyrosine and tryptophan) allowing them to form chemical interactions with their associated RNA regions, such as stacking interactions. Ribosomal proteins can also cross-link to the sugar-phosphate bac
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https://en.wikipedia.org/wiki/Four-gradient
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In differential geometry, the four-gradient (or 4-gradient) is the four-vector analogue of the gradient from vector calculus.
In special relativity and in quantum mechanics, the four-gradient is used to define the properties and relations between the various physical four-vectors and tensors.
Notation
This article uses the metric signature.
SR and GR are abbreviations for special relativity and general relativity respectively.
indicates the speed of light in vacuum.
is the flat spacetime metric of SR.
There are alternate ways of writing four-vector expressions in physics:
The four-vector style can be used: , which is typically more compact and can use vector notation, (such as the inner product "dot"), always using bold uppercase to represent the four-vector, and bold lowercase to represent 3-space vectors, e.g. . Most of the 3-space vector rules have analogues in four-vector mathematics.
The Ricci calculus style can be used: , which uses tensor index notation and is useful for more complicated expressions, especially those involving tensors with more than one index, such as .
The Latin tensor index ranges in and represents a 3-space vector, e.g. .
The Greek tensor index ranges in and represents a 4-vector, e.g. .
In SR physics, one typically uses a concise blend, e.g. , where represents the temporal component and represents the spatial 3-component.
Tensors in SR are typically 4D -tensors, with upper indices and lower indices, with the 4D indicating 4
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https://en.wikipedia.org/wiki/SIRT
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SIRT can refer to :
Selective internal radiation therapy for cancer
Serious Incident Response Team, Nova Scotia, Canada
Sirtuin, a class of proteins (enzymes) related to genetics
Staten Island Railway (from abbreviation Staten Island Rapid Transit)
See also
Siirt, a city in Turkey
Sirt, another name for Sirte, a city in Libya
Sirte (disambiguation)
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https://en.wikipedia.org/wiki/This%20Week%20%281956%20TV%20programme%29
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This Week was a British weekly current affairs television programme that was first produced for ITV in January 1956 by Associated-Rediffusion (later Thames Television) and Rediffusion, running until 1978, when it was replaced by TV Eye. In 1986, the earlier name was revived and This Week continued until Thames lost its franchise at the end of 1992.
In September 1958, This Week filmed George Harrison Marks and Pamela Green at their photography studio in Gerrard Street. David Kentick directed and Nick Barker interviewed Marks and Green. They were filmed working with a nude model, who was strategically covered by a very long wig. The film sequence ended with a montage of their photographs, mostly of nudes. However, the night it was to be broadcast Pope Pius XII died and the programme was cut, and the interview never shown. In 1964, This Week returned to their studio. This time round they showed a clip of the infamous striptease comedy film The Window Dresser.
However, its most influential episode was an exposé on the National Front in 1974, which led to the party's members firing their Chairman John Tyndall and National Activities Organiser Martin Webster two weeks later as a result of the revelations on the show from former NF Chairman John O'Brien of their neo-Nazi paramilitary pasts and continued links.
In 1976 the episode Death in the West believed to contain the first recorded admission from a tobacco company representative that smoking causes health problems resulted in
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https://en.wikipedia.org/wiki/Lorenz%20gauge%20condition
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In electromagnetism, the Lorenz gauge condition or Lorenz gauge (after Ludvig Lorenz) is a partial gauge fixing of the electromagnetic vector potential by requiring The name is frequently confused with Hendrik Lorentz, who has given his name to many concepts in this field. The condition is Lorentz invariant. The Lorenz gauge condition does not completely determine the gauge: one can still make a gauge transformation where is the four-gradient and is any harmonic scalar function: that is, a scalar function obeying the equation of a massless scalar field.
The Lorenz gauge condition is used to eliminate the redundant spin-0 component in Maxwell's equations when these are used to describe a massless spin-1 quantum field. It is also used for massive spin-1 fields where the concept of gauge transformations does not apply at all.
Description
In electromagnetism, the Lorenz condition is generally used in calculations of time-dependent electromagnetic fields through retarded potentials. The condition is
where is the four-potential, the comma denotes a partial differentiation and the repeated index indicates that the Einstein summation convention is being used. The condition has the advantage of being Lorentz invariant. It still leaves substantial gauge degrees of freedom.
In ordinary vector notation and SI units, the condition is
where is the magnetic vector potential and is the electric potential; see also gauge fixing.
In Gaussian units the condition is
A quick just
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https://en.wikipedia.org/wiki/Mountains%20classification%20in%20the%20Tour%20de%20France
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The mountains classification is a secondary competition in the Tour de France, that started in 1933. It is given to the rider that gains the most points for reaching mountain summits first. The leader of the classification is named the King of the Mountains, and since 1975 wears the polka dot jersey (), a white jersey with red polka dots.
History
The first Tour de France crossed no mountain passes, but several lesser cols. The first was the col des Echarmeaux (), on the opening stage from Paris to Lyon, on what is now the old road from Autun to Lyon. The stage from Lyon to Marseille included the col de la République (), also known as the col du Grand Bois, at the edge of St-Etienne. The first major climb—the Ballon d'Alsace () in the Vosges — was featured in the 1905 race.
True mountains were not included until the Pyrenees in 1910. In that year the race rode, or more walked, first the col d'Aubisque and then the nearby Tourmalet. Both climbs were mule tracks, a demanding challenge on heavy, ungeared bikes ridden by men with spare tires around their shoulders and their food, clothing and tools in bags hung from their handlebars. The assistant organiser, Victor Breyer, stood at the summit of the Aubisque with the colleague who had proposed including the Pyrenees, Alphonse Steinès. The tour organiser, Henri Desgrange was confident enough after the Pyrenees to include the Alps in 1911.
The highest climb in the race was the Cime de la Bonette-Restefond in the 1962 Tour de Fra
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https://en.wikipedia.org/wiki/Viral%20hemorrhagic%20fever
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Viral hemorrhagic fevers (VHFs) are a diverse group of animal and human illnesses. VHFs may be caused by five distinct families of RNA viruses: the families Filoviridae, Flaviviridae, Rhabdoviridae, and several member families of the Bunyavirales order such as Arenaviridae, and Hantaviridae. All types of VHF are characterized by fever and bleeding disorders and all can progress to high fever, shock and death in many cases. Some of the VHF agents cause relatively mild illnesses, such as the Scandinavian nephropathia epidemica (a hantavirus), while others, such as Ebola virus, can cause severe, life-threatening disease.
Signs and symptoms
Signs and symptoms of VHFs include (by definition) fever and bleeding:
Flushing of the face and chest, small red or purple spots (petechiae), bleeding, swelling caused by edema, low blood pressure (hypotension), and circulatory shock.
Malaise, muscle pain, headache, vomiting, and diarrhea occur frequently.
The severity of symptoms varies with the type of virus. The "VHF syndrome" (capillary leak, bleeding diathesis, and circulatory compromise leading to shock) appears in a majority of people with filoviral hemorrhagic fevers (e.g., Ebola and Marburg virus), Crimean–Congo hemorrhagic fever (CCHF), and the South American hemorrhagic fevers caused by arenaviruses, but only in a small minority of patients with dengue or Rift Valley fever.
Causes
Five families of RNA viruses have been recognised as being able to cause hemorrhagic fevers.
The
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https://en.wikipedia.org/wiki/HBP
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HBP may refer to:
High blood pressure or hypertension
Heparin-binding protein or azurocidin 1, protein-coding gene in the species Homo sapiens
Hairpin-binding protein, protein-coding gene in humans
Human Brain Project, scientific research project
Harvard Business Publishing, US publishing company
Hit by pitch, baseball event in which the batter is hit by the pitched ball
Hornbeam Park railway station, railway station in North Yorkshire, England
Home buyers' plan, type of financial account in Canada for holding savings and investment assets
See also
Harry Potter and the Half-Blood Prince
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https://en.wikipedia.org/wiki/Mascagnite
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Mascagnite is a rare ammonium sulfate mineral (NH4)2SO4. It crystallizes in the orthorhombic system typically forming as stalactitic masses exhibiting good cleavage. It is soft (not higher than 2.5 on the Mohs Scale) and water-soluble. Optical properties are variable; the purest form is transparent and colorless, but opaque gray or yellow deposits are also known.
It occurs in fumaroles, as at Mount Vesuvius and associated with coal seam fires. It was named for Italian anatomist Paolo Mascagni (1752–1815) who first described the mineral.
References
Ammonium minerals
Sulfate minerals
Orthorhombic minerals
Minerals in space group 62
Mount Vesuvius
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https://en.wikipedia.org/wiki/Hardiness%20zone
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A hardiness zone is a geographic area defined as having a certain average annual minimum temperature, a factor relevant to the survival of many plants. In some systems other statistics are included in the calculations. The original and most widely used system, developed by the United States Department of Agriculture (USDA) as a rough guide for landscaping and gardening, defines 13 zones by long-term average annual extreme minimum temperatures. It has been adapted by and to other countries (such as Canada) in various forms.
Unless otherwise specified, in American contexts "hardiness zone" or simply "zone" usually refers to the USDA scale. For example, a plant may be described as "hardy to zone 10": this means that the plant can withstand a minimum temperature of 30 °F (−1.1 °C) to 40 °F (4.4 °C).
Other hardiness rating schemes have been developed as well, such as the UK Royal Horticultural Society and US Sunset Western Garden Book systems. A heat zone (see below) is instead defined by annual high temperatures; the American Horticultural Society (AHS) heat zones use the average number of days per year when the temperature exceeds .
United States hardiness zones (USDA scale)
The USDA system was originally developed to aid gardeners and landscapers in the United States.
State-by-state maps, along with an electronic system that allows finding the zone for a particular zip code, can be found at the USDA Agricultural Research Service (USDA-ARS) website.
In the United States, m
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https://en.wikipedia.org/wiki/Killing%20horizon
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In physics, a Killing horizon is a geometrical construct used in general relativity and its generalizations to delineate spacetime boundaries without reference to the dynamic Einstein field equations. Mathematically a Killing horizon is a null hypersurface defined by the vanishing of the norm of a Killing vector field (both are named after Wilhelm Killing). It can also be defined as a null hypersurface generated by a Killing vector, which in turn is null at that surface.
After Hawking showed that quantum field theory in curved spacetime (without reference to the Einstein field equations) predicted that a black hole formed by collapse will emit thermal radiation, it became clear that there is an unexpected connection between spacetime geometry (Killing horizons) and thermal effects for quantum fields. In particular, there is a very general relationship between thermal radiation and spacetimes that admit a one-parameter group of isometries possessing a bifurcate Killing horizon, which consists of a pair of intersecting null hypersurfaces that are orthogonal to the Killing field.
Flat spacetime
In Minkowski space-time, in pseudo-Cartesian coordinates with signature an example of Killing horizon is provided by the Lorentz boost (a Killing vector of the space-time)
The square of the norm of is
Therefore, is null only on the hyperplanes of equations
that, taken together, are the Killing horizons generated by .
Black hole Killing horizons
Exact black hole metrics s
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https://en.wikipedia.org/wiki/NUTS%20statistical%20regions%20of%20the%20Czech%20Republic
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The Nomenclature of Territorial Units for Statistics (NUTS) is a geocode standard for referencing the subdivisions of the Czech Republic for statistical purposes. The standard is developed and regulated by the European Union. The NUTS standard is instrumental in delivering the European Union's Structural Funds. The NUTS code for the Czech Republic is CZ and a hierarchy of three levels is established by Eurostat. Below these is a further levels of geographic organisation - the local administrative unit (LAU). In the Czech Republic, the LAU 1 is districts and the LAU 2 is municipalities.
Overall
NUTS codes
In the 2003 version, the Vysočina Region was coded CZ061, and the South Moravian Region was coded CZ062.
Local administrative units
Below the NUTS levels, the two LAU (Local Administrative Units) levels are:
The LAU codes of the Czech Republic can be downloaded here: ''
See also
List of Czech regions by Human Development Index
Subdivisions of the Czech Republic
ISO 3166-2 codes of the Czech Republic
FIPS region codes of the Czech Republic
References
Sources
Hierarchical list of the Nomenclature of territorial units for statistics - NUTS and the Statistical regions of Europe
Overview map of EU Countries - NUTS level 1
Correspondence between the NUTS levels and the national administrative units
List of current NUTS codes
Download current NUTS codes (ODS format)
Regions of the Czech Republic, Statoids.com
Districts of the Czech Republic, Statoids.com
Extern
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https://en.wikipedia.org/wiki/Heterojunction%20bipolar%20transistor
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The heterojunction bipolar transistor (HBT) is a type of bipolar junction transistor (BJT) which uses differing semiconductor materials for the emitter and base regions, creating a heterojunction. The HBT improves on the BJT in that it can handle signals of very high frequencies, up to several hundred GHz. It is commonly used in modern ultrafast circuits, mostly radio frequency (RF) systems, and in applications requiring a high power efficiency, such as RF power amplifiers in cellular phones. The idea of employing a heterojunction is as old as the conventional BJT, dating back to a patent from 1951. Detailed theory of heterojunction bipolar transistor was developed by Herbert Kroemer in 1957.
Materials
The principal difference between the BJT and HBT is in the use of differing semiconductor materials for the emitter-base junction and the base-collector junction, creating a heterojunction. The effect is to limit the injection of holes from the base into the emitter region, since the potential barrier in the valence band is higher than in the conduction band. Unlike BJT technology, this allows a high doping density to be used in the base, reducing the base resistance while maintaining gain. The efficiency of the heterojunction is measured by the Kroemer factor. Kroemer was awarded a Nobel Prize in 2000 for his work in this field at the University of California, Santa Barbara.
Materials used for the substrate include silicon, gallium arsenide, and indium phosphide, while si
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https://en.wikipedia.org/wiki/Bloop
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Bloop was an ultra-low-frequency, high amplitude underwater sound detected by the U.S. National Oceanic and Atmospheric Administration (NOAA) in 1997. By 2012, earlier speculation that the sound originated from a marine animal was replaced by NOAA's description of the sound as being consistent with noises generated via non-tectonic cryoseisms originating from glacial movements such as ice calving, or through seabed gouging by ice.
Sound profile
The sound's source was roughly triangulated to , a remote point in the south Pacific Ocean west of the southern tip of South America. The sound was detected by the Equatorial Pacific Ocean autonomous hydrophone array, a system of hydrophones primarily used to monitor undersea seismicity, ice noise, and marine mammal population and migration. This is a stand-alone system designed and built by NOAA's Pacific Marine Environmental Laboratory (PMEL) to augment NOAA's use of the U.S. Navy Sound Surveillance System (SOSUS), which was equipment originally designed to detect Soviet submarines.
According to the NOAA description, the sound "rose" in frequency over about one minute and was of sufficient amplitude to be heard on multiple sensors, at a range of over .
Ice quake origin
The NOAA Vents Program has attributed the sound to that of a large cryoseism (also known as an ice quake). Numerous ice quakes share similar spectrograms with Bloop, as well as the amplitude necessary to detect them despite ranges exceeding . This was found during
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https://en.wikipedia.org/wiki/Ashtamudi%20Lake
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Ashtamudi Lake (Ashtamudi Kayal), in the Kollam District of the Indian state of Kerala. It possesses a unique wetland ecosystem and a large palm-shaped (also described as octopus-shaped) water body, second only in size to the Vembanad estuary ecosystem of the state. Ashtamudi means 'eight braids' (Ashta : 'eight'; mudi : 'hair braids') in the local Malayalam language. The name is indicative of the lake's topography with its multiple branches. The lake is also called the gateway to the backwaters of Kerala and is well known for its houseboat and backwater resorts.
Ashtamudi Wetland was included in the list of wetlands of international importance, as defined by the Ramsar Convention for the conservation and sustainable utilization of wetlands.
Along both banks of the lake and its backwater canals, coconut groves and palm trees interspersed with towns and villages are seen. Kollam, (formerly Quilon) is an important historic port city located on the right bank of the lake. Boat cruises are operated by the Kollam Boat Club from Kollam to Alappuzha providing transport access to many other towns and villages along this route. Luxury houseboats also operate on the lake. The boat journey is an 8-hour trip, winding through lakes, canals and water bound villages. Chinese fishing nets, called cheena vala in Malayalam, are used by local fisherman and are a common sight along the waterway.
The lake and the city of Kollam on its banks and the Neendakara port at the confluence offer a mean
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https://en.wikipedia.org/wiki/Fourth%2C%20fifth%2C%20and%20sixth%20derivatives%20of%20position
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In physics, the fourth, fifth and sixth derivatives of position are defined as derivatives of the position vector with respect to time – with the first, second, and third derivatives being velocity, acceleration, and jerk, respectively. The higher-order derivatives are less common than the first three, thus their names are not as standardized, though the concept of a minimum snap trajectory has been used in robotics and is implemented in MATLAB.
The fourth derivative is often referred to as snap or jounce. The name "snap" for the fourth derivative led to crackle and pop for the fifth and sixth derivatives respectively, inspired by the Rice Krispies mascots Snap, Crackle, and Pop. These terms are occasionally used, though "sometimes somewhat facetiously".
(snap/jounce)
Snap, or jounce, is the fourth derivative of the position vector with respect to time, or the rate of change of the jerk with respect to time. Equivalently, it is the second derivative of acceleration or the third derivative of velocity,
and is defined by any of the following equivalent expressions:
In civil engineering, the design of railway tracks and roads involves the minimization of snap, particularly around bends with different radii of curvature. When snap is constant, the jerk changes linearly, allowing for a smooth increase in radial acceleration, and when, as is preferred, the snap is zero, the change in radial acceleration is linear. The minimization or elimination of snap is commonly done using a m
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https://en.wikipedia.org/wiki/Murashige%20and%20Skoog%20medium
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Murashige and Skoog medium (or MSO or MS0 (MS-zero)) is a plant growth medium used in the laboratories for cultivation of plant cell culture. MS0 was invented by plant scientists Toshio Murashige and Folke K. Skoog in 1962 during Murashige's search for a new plant growth regulator. A number behind the letters MS is used to indicate the sucrose concentration of the medium. For example, MS0 contains no sucrose and MS20 contains 20 g/L sucrose. Along with its modifications, it is the most commonly used medium in plant tissue culture experiments in the laboratory. However, according to recent scientific findings, MS medium is not suitable as a nutrient solution for deep water culture or hydroponics.
As Skoog's doctoral student, Murashige originally set out to find an as-yet undiscovered growth hormone present in tobacco juice. No such component was discovered; instead, analysis of juiced tobacco and ashed tobacco revealed higher concentrations of specific minerals in plant tissues than were previously known. A series of experiments demonstrated that varying the levels of these nutrients enhanced growth substantially over existing formulations. It was determined that nitrogen in particular enhanced growth of tobacco in tissue culture.
Ingredients
Major salts (macronutrients) per litre
Ammonium nitrate (NH4NO3) 1650 mg/l
Calcium chloride (CaCl2 · 2H2O) 440 mg/l
Magnesium sulfate (MgSO4 · 7H2O) 180.7 mg/l
Monopotassium phosphate (KH2PO4) 170 mg/l
Potassium nitrate (KNO3) 1900 mg
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https://en.wikipedia.org/wiki/TCP%20congestion%20control
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Transmission Control Protocol (TCP) uses a congestion control algorithm that includes various aspects of an additive increase/multiplicative decrease (AIMD) scheme, along with other schemes including slow start and congestion window (CWND), to achieve congestion avoidance. The TCP congestion-avoidance algorithm is the primary basis for congestion control in the Internet. Per the end-to-end principle, congestion control is largely a function of internet hosts, not the network itself. There are several variations and versions of the algorithm implemented in protocol stacks of operating systems of computers that connect to the Internet.
To avoid congestive collapse, TCP uses multi-faceted congestion-control strategy. For each connection, TCP maintains a CWND, limiting the total number of unacknowledged packets that may be in transit end-to-end. This is somewhat analogous to TCP's sliding window used for flow control.
Additive increase/multiplicative decrease
The additive increase/multiplicative decrease (AIMD) algorithm is a closed-loop control algorithm. AIMD combines linear growth of the congestion window with an exponential reduction when a congestion takes place. Multiple flows using AIMD congestion control will eventually converge to use equal amounts of a contended link.
This is the algorithm that is described in for the "congestion avoidance" state.
Congestion window
In TCP, the congestion window (CWND) is one of the factors that determines the number of bytes that
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https://en.wikipedia.org/wiki/Daibhidh%20%C3%93%20Duibhgheann%C3%A1in
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Dáibhídh Ó Duibhgeannáin (fl. 1651–1696), also known as Dáibhídh mac Matthew Glas Ó Duibhgeannáin or Dáibhídh Bacach ("lame David"), was a scribe, compiler and poet who was active between the years 1651 and 1696. In the earliest of his known works, Royal Irish Academy Ms. 24.P.9., he writes on page 238: "sguirim go ttrasada ar Loch Mesg dam a ttigh Thaidgh Oig Ui Fhlaibhertaigh 1 die Aprilis 1651, Dauid Duigenan qui scripsit/I stop now, and I on Loch Mask in the house of Tadhg Og O Flaherty, April 1st, 1651, David Duigenan who wrote this." A later entry specifies the place as Oileán Ruadh, or Red Island.
There is a slight chance that he may have been the (or an) intermediary responsible for presenting Dubhaltach MacFhirbhisigh with "Volume C" of the original four volumes of the autograph of the Annals of the Four Masters, covering the period AM 2242 to AD 1171. Peregrine O'Duignan, one of the four main responsible for compiling the book, was a kinsman of Dáibhídh's. However, an idea proposed by the writer of this article that Dáibhídh was MacFhirbhisigh's mysterious amanuensis cannot be sustained, as a comparison of their handwriting bears no resemblance to each other.
Throughout his life, he transcribed such works as "Suibhne Gelt/The Frenzy of Sweeney", "The Adventures of the Two Idiot Saints", "The Battle of Magh Rath", and "The Banquet of Dun na Gedh.". He is believed to have lived his final years in Shancough, Tirerrill, County Sligo, where he lived with his wife, a Ma
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https://en.wikipedia.org/wiki/Lupus%20%28disambiguation%29
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Lupus commonly refers to many lupus erythematosus autoimmune diseases, including systemic lupus erythematosus. See lupus erythematosus#Classification for links to the many Wikipedia articles.
Lupus may also refer to:
Arts and entertainment
Lupus, a character in The Roman Mysteries
Lupus, a dog in the video game Jet Force Gemini
"Lupus", in Trash: Short Stories by Dorothy Allison
People
Lupus (name), a given name and a family name
Pen name of Wulfstan (died 956), Archbishop of York
Hugh d'Avranches, 1st Earl of Chester, nicknamed Lupus (wolf) for his ferocity
Other uses
Lupus (constellation)
Lupus (journal), a journal in the field of rheumatology
Lupus, Missouri, a US city
Lupus vulgaris, cutaneous tuberculosis
Latin word for wolf
See also
Toshiba Brave Lupus, a Japanese rugby team
Lupis (disambiguation)
Lapis (disambiguation)
Canis lupus, the wolf
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https://en.wikipedia.org/wiki/Digesting%20Duck
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The Canard Digérateur, or Digesting Duck, was an automaton in the form of a duck, created by Jacques de Vaucanson and unveiled on 30 May 1764 in France. The mechanical duck appeared to have the ability to eat kernels of grain, and to metabolize and defecate them. While the duck did not actually have the ability to do this—the food was collected in one inner container, and the pre-stored feces were "produced" from a second, so that no actual digestion took place—Vaucanson hoped that a truly digesting automaton could one day be designed.
Voltaire wrote in 1769 that ('Without the voice of le Maure and Vaucanson's duck, you would have nothing to remind you of the glory of France.')
The duck is thought to have been destroyed in a fire at a museum in 1879.
Operation
The automaton was the size of a living duck, and was cased in gold-plated copper. As well as quacking and muddling water with its bill, it appeared capable of drinking water, and of taking food from its operator's hand, swallowing it with a gulping action and excreting what appeared to be a digested version of it.
Vaucanson described the duck's interior as containing a small "chemical laboratory" capable of breaking down the grain. When the stage magician and automaton builder Jean-Eugène Robert-Houdin examined the duck in 1844, he found that Vaucanson had faked the mechanism, and the duck's excreta consisted of pre-prepared breadcrumb pellets, dyed green. Robert-Houdin described this as "a piece of artifice I wou
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https://en.wikipedia.org/wiki/NUTS%20statistical%20regions%20of%20Ireland
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Ireland uses the Nomenclature of Territorial Units for Statistics (NUTS) geocode standard for referencing country subdivisions for statistical purposes. The standard is developed and regulated by the European Union. The NUTS standard is instrumental in delivering European Structural and Investment Funds. The NUTS code for Ireland is IE and a hierarchy of three levels is established by Eurostat. A further level of geographic organisation, the local administrative unit (LAU), in Ireland is the local electoral area.
Overview
NUTS levels 1, 2 and 3
The most recent revision of NUTS regions was made in 2016 and took effect in 2018. The eligibility of regions for funding under the European Regional Development Fund and the European Social Fund Plus was revised in 2021. NUTS 2 Regions may be classified as less developed regions, transition regions, or more developed regions.
Demographic statistics by NUTS 3 region
Local administrative units
The local administrative units in Ireland are the local electoral areas. These are subdivisions of local government areas used for local elections. In counties outside Dublin and in the cities and counties, they also form the basis of municipal districts within local authorities.
Regional Assemblies
Each of the three NUTS 2 regions has a Regional Assembly. These are divided into strategic planning areas, which correspond to the NUTS 3 regions. Prior to 2014, the eight NUTS 3 regions had Regional Authorities. The 2014 act abolished these and t
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https://en.wikipedia.org/wiki/Mathieu%20function
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In mathematics, Mathieu functions, sometimes called angular Mathieu functions, are solutions of Mathieu's differential equation
where are real-valued parameters. Since we may add to to change the sign of , it is a usual convention to set .
They were first introduced by Émile Léonard Mathieu, who encountered them while studying vibrating elliptical drumheads. They have applications in many fields of the physical sciences, such as optics, quantum mechanics, and general relativity. They tend to occur in problems involving periodic motion, or in the analysis of partial differential equation (PDE) boundary value problems possessing elliptic symmetry.
Definition
Mathieu functions
In some usages, Mathieu function refers to solutions of the Mathieu differential equation for arbitrary values of and . When no confusion can arise, other authors use the term to refer specifically to - or -periodic solutions, which exist only for special values of and . More precisely, for given (real) such periodic solutions exist for an infinite number of values of , called characteristic numbers, conventionally indexed as two separate sequences and , for . The corresponding functions are denoted and , respectively. They are sometimes also referred to as cosine-elliptic and sine-elliptic, or Mathieu functions of the first kind.
As a result of assuming that is real, both the characteristic numbers and associated functions are real-valued.
and can be further classified by parity and per
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https://en.wikipedia.org/wiki/Allerion
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Allerion may refer to:
Charge (heraldry)
Ultimate Corp; see Pick Operating System#Derivative and related products
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https://en.wikipedia.org/wiki/Cauchy%20boundary%20condition
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In mathematics, a Cauchy () boundary condition augments an ordinary differential equation or a partial differential equation with conditions that the solution must satisfy on the boundary; ideally so as to ensure that a unique solution exists. A Cauchy boundary condition specifies both the function value and normal derivative on the boundary of the domain. This corresponds to imposing both a Dirichlet and a Neumann boundary condition. It is named after the prolific 19th-century French mathematical analyst Augustin-Louis Cauchy.
Second-order ordinary differential equations
Cauchy boundary conditions are simple and common in second-order ordinary differential equations,
where, in order to ensure that a unique solution exists, one may specify the value of the function and the value of the derivative at a given point , i.e.,
and
where is a boundary or initial point. Since the parameter is usually time, Cauchy conditions can also be called initial value conditions or initial value data or simply Cauchy data. An example of such a situation is Newton's laws of motion, where the acceleration depends on position , velocity , and the time ; here, Cauchy data corresponds to knowing the initial position and velocity.
Partial differential equations
For partial differential equations, Cauchy boundary conditions specify both the function and the normal derivative on the boundary. To make things simple and concrete, consider a second-order differential equation in the plane
whe
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https://en.wikipedia.org/wiki/Cauchy%20problem
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A Cauchy problem in mathematics asks for the solution of a partial differential equation that satisfies certain conditions that are given on a hypersurface in the domain. A Cauchy problem can be an initial value problem or a boundary value problem (for this case see also Cauchy boundary condition). It is named after Augustin-Louis Cauchy.
Formal statement
For a partial differential equation defined on Rn+1 and a smooth manifold S ⊂ Rn+1 of dimension n (S is called the Cauchy surface), the Cauchy problem consists of finding the unknown functions of the differential equation with respect to the independent variables that satisfies
subject to the condition, for some value ,
where are given functions defined on the surface (collectively known as the Cauchy data of the problem). The derivative of order zero means that the function itself is specified.
Cauchy–Kowalevski theorem
The Cauchy–Kowalevski theorem states that If all the functions are analytic in some neighborhood of the point , and if all the functions are analytic in some neighborhood of the point , then the Cauchy problem has a unique analytic solution in some neighborhood of the point .
See also
Cauchy boundary condition
Cauchy horizon
References
External links
Cauchy problem at MathWorld.
Partial differential equations
Mathematical problems
Boundary value problems
de:Anfangswertproblem#Partielle Differentialgleichungen
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https://en.wikipedia.org/wiki/NUTS%20statistical%20regions%20of%20the%20Netherlands
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In the NUTS (Nomenclature of Territorial Units for Statistics) codes of the Netherlands (NL), the three levels are:
NUTS codes
Local administrative units
Below the NUTS levels, the two LAU (Local Administrative Units) levels are:
The LAU codes of the Netherlands can be downloaded here:
See also
Subdivisions of the Netherlands
ISO 3166-2 codes of the Netherlands
FIPS region codes of the Netherlands
References
External links
Hierarchical list of the Nomenclature of territorial units for statistics - NUTS and the Statistical regions of Europe
Overview map of EU Countries - NUTS level 1
NEDERLAND - NUTS level 2
NEDERLAND - NUTS level 3
Correspondence between the NUTS levels and the national administrative units
List of current NUTS codes
Download current NUTS codes (ODS format)
Provinces of Netherlands, Statoids.com
Netherlands
Nuts
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https://en.wikipedia.org/wiki/List%20of%20French%20Open%20men%27s%20doubles%20champions
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Champions
French Championships
French Open
Statistics
Multiple champions
Champions by country
If the doubles partners are from the same country then that country gets two titles instead of one, while if they are from different countries then each country will get one title apiece.
Notes
References
See also
French Open other competitions
List of French Open men's singles champions
List of French Open women's singles champions
List of French Open women's doubles champions
List of French Open mixed doubles champions
Grand Slam men's doubles
List of Australian Open men's doubles champions
List of Wimbledon gentlemen's doubles champions
List of US Open men's doubles champions
List of Grand Slam men's doubles champions
Mens
Lists of male tennis players
French Open champions
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https://en.wikipedia.org/wiki/Relativistic%20Breit%E2%80%93Wigner%20distribution
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The relativistic Breit–Wigner distribution (after the 1936 nuclear resonance formula of Gregory Breit and Eugene Wigner) is a continuous probability distribution with the following probability density function,
where is a constant of proportionality, equal to
with
(This equation is written using natural units, .)
It is most often used to model resonances (unstable particles) in high-energy physics. In this case, is the center-of-mass energy that produces the resonance, is the mass of the resonance, and Γ is the resonance width (or decay width), related to its mean lifetime according to . (With units included, the formula is .)
Usage
The probability of producing the resonance at a given energy is proportional to , so that a plot of the production rate of the unstable particle as a function of energy traces out the shape of the relativistic Breit–Wigner distribution. Note that for values of off the maximum at such that , (hence for ), the distribution has attenuated to half its maximum value, which justifies the name for Γ, width at half-maximum.
In the limit of vanishing width, Γ → 0, the particle becomes stable as the Lorentzian distribution sharpens infinitely to .
In general, Γ can also be a function of ; this dependence is typically only important when Γ is not small compared to and the phase space-dependence of the width needs to be taken into account. (For example, in the decay of the rho meson into a pair of pions.) The factor of 2 that multipl
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https://en.wikipedia.org/wiki/Ionophore
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In chemistry, an ionophore () is a chemical species that reversibly binds ions. Many ionophores are lipid-soluble entities that transport ions across the cell membrane. Ionophores catalyze ion transport across hydrophobic membranes, such as liquid polymeric membranes (carrier-based ion selective electrodes) or lipid bilayers found in the living cells or synthetic vesicles (liposomes). Structurally, an ionophore contains a hydrophilic center and a hydrophobic portion that interacts with the membrane.
Some ionophores are synthesized by microorganisms to import ions into their cells. Synthetic ion carriers have also been prepared. Ionophores selective for cations and anions have found many applications in analysis. These compounds have also shown to have various biological effects and a synergistic effect when combined with the ion they bind.
Classification
Biological activities of metal ion-binding compounds can be changed in response to the increment of the metal concentration, and based on the latter compounds can be classified as "metal ionophores", "metal chelators" or "metal shuttles". If the biological effect is augmented by increasing the metal concentration, it is classified as a "metal ionophore". If the biological effect is decreased or reversed by increasing the metal concentration, it is classified as a "metal chelator". If the biological effect is not affected by increasing the metal concentration, and the compound-metal complex enters the cell, it is classifie
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https://en.wikipedia.org/wiki/Neural%20circuit
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A neural circuit (also known as a biological neural network BNNs) is a population of neurons interconnected by synapses to carry out a specific function when activated. Multiple neural circuits interconnect with one another to form large scale brain networks.
Neural circuits have inspired the design of artificial neural networks, though there are significant differences.
Early study
Early treatments of neural networks can be found in Herbert Spencer's Principles of Psychology, 3rd edition (1872), Theodor Meynert's Psychiatry (1884), William James' Principles of Psychology (1890), and Sigmund Freud's Project for a Scientific Psychology (composed 1895). The first rule of neuronal learning was described by Hebb in 1949, in the Hebbian theory. Thus, Hebbian pairing of pre-synaptic and post-synaptic activity can substantially alter the dynamic characteristics of the synaptic connection and therefore either facilitate or inhibit signal transmission. In 1959, the neuroscientists, Warren Sturgis McCulloch and Walter Pitts published the first works on the processing of neural networks. They showed theoretically that networks of artificial neurons could implement logical, arithmetic, and symbolic functions. Simplified models of biological neurons were set up, now usually called perceptrons or artificial neurons. These simple models accounted for neural summation (i.e., potentials at the post-synaptic membrane will summate in the cell body). Later models also provided for excitatory
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https://en.wikipedia.org/wiki/Intergenic%20region
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An intergenic region is a stretch of DNA sequences located between genes. Intergenic regions may contain functional elements and junk DNA.
Properties and functions
Intergenic regions may contain a number of functional DNA sequences such as promoters and regulatory elements, enhancers, spacers, and (in eukaryotes) centromeres. They may also contain origins of replication, scaffold attachment regions, and transposons and viruses. Non-functional DNA elements such as pseudogenes and repetitive DNA, both of which are types of junk DNA, can also be found in intergenic regions—although they may also be located within genes in introns.
As all scientific knowledge is ultimately tentative—and in principle subject to revision given better evidence—it is possible some well-characterized intergenic regions (but also intra-genic regions like introns) may hypothetically contain as yet unidentified functional elements, such as non-coding RNA genes or regulatory sequences. Such discoveries occur from time to time, but the amount of functional DNA discovered usually constitute only a tiny fraction of the overall amount of intergenic/intronic DNA.
Intergenic regions in different organisms
In humans, intergenic regions comprise about 50% of the genome, whereas this number is much less in bacteria (15%) and yeast (30%).
As with most other non-coding DNA, the GC-content of intergenic regions vary considerably among species. For example in Plasmodium falciparum, many intergenic reg
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https://en.wikipedia.org/wiki/Intake
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An intake (also inlet) is an opening, structure or system through which a fluid is admitted to a space or machine as a consequence of a pressure differential between the outside and the inside. The pressure difference may be generated on the inside by a mechanism, or on the outside by ram pressure or hydrostatic pressure. Flow rate through the intake depends on pressure difference, fluid properties, and intake geometry.
Intake refers to an opening, or area, together with its defining edge profile which has an associated entry loss, that captures pipe flow from a reservoir or storage tank. Intake refers to the capture area definition and attached ducting to an aircraft gas turbine engine or ramjet engine and, as such, an intake is followed by a compressor or combustion chamber. It may instead be referred to as a diffuser. For an automobile engine the components through which the air flows to the engine cylinders, are collectively known as an intake system and may include the inlet port and valve. An intake for a hydroelectric power plant is the capture area in a reservoir which feeds a pressure pipe, or penstock, or into an open canal.
Automobile engine intakes
Early automobile intake systems were simple air inlets connected directly to carburetors. The first air filter was implemented on the 1915 Packard Twin Six.
The modern automobile air intake system has three main parts, an air filter, mass flow sensor, and throttle body. Some modern intake systems can be highly comp
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https://en.wikipedia.org/wiki/Chinese%20character%20classification
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All Chinese characters are logograms, but several different types can be identified, based on the manner in which they are formed or derived. There are a handful which derive from pictographs () and a number which are ideographic () in origin, including compound ideographs (), but the vast majority originated as phono-semantic compounds (). The other categories in the traditional system of classification are rebus or phonetic loan characters () and "derivative cognates" (). Modern scholars have proposed various revised systems, rejecting some of the traditional categories.
In older literature, Chinese characters in general may be referred to as ideograms, due to the misconception that characters represented ideas directly, whereas some people assert that they do so only through association with the spoken word.
Traditional classification
Traditional Chinese lexicography divided characters into six categories (). This classification is known from Xu Shen's second century dictionary Shuowen Jiezi, but did not originate there. The phrase first appeared in the Rites of Zhou, though it may not have originally referred to methods of creating characters. When Liu Xin (d. 23 CE) edited the Rites, he glossed the term with a list of six types without examples.
Slightly different lists of six types are given in the Book of Han of the first century CE, and by Zheng Zhong quoted by Zheng Xuan in his first-century commentary on the Rites of Zhou.
Xu Shen illustrated each of Liu's six typ
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https://en.wikipedia.org/wiki/Lowland%20East%20Cushitic%20languages
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Lowland East Cushitic is a group of roughly two dozen diverse languages of the Cushitic branch of the Afro-Asiatic family. Its largest representatives are Oromo and Somali.
Classification
Lowland East Cushitic classification from Tosco (2020:297):
Lowland East Cushitic
Saho–Afar
Southern
Nuclear
Omo–Tana
Oromoid
Peripheral (?)
Dullay
Yaaku
Highland East Cushitic is a coordinate (sister) branch with Lowland East Cushitic in Tosco's (2020) classification.
'Core' East Cushitic classification form Bender (2020 [2008]: 91). Saho–Afar is excluded, making it equivalent to Tosco's Southern Lowland East Cushitic, and Yaaku is moved into Western Omo–Tana ('Arboroid'):
'Core' East Cushitic
Dullay
SAOK
Eastern Omo–Tana (Somaloid)
Western Omo–Tana (Arboroid) [incl. Yaaku]
Oromoid (Oromo–Konsoid)
Highland East Cushitic and Afar–Saho are coordinate (sister) branches with Lowland East Cushitic, together forming East Cushitic.
Overview
Lowland East Cushitic is often grouped with Highland East Cushitic (the Sidamic languages), Dullay, and Yaaku as East Cushitic, but that group is not well defined and considered dubious.
The most spoken Lowland East Cushitic language is Oromo, with about 35 million speakers in Ethiopia and Kenya. The Konsoid dialect cluster is closely related to Oromo. Other prominent languages include Somali (spoken by ethnic Somalis in Somalia, Somaliland, Ethiopia, Djibouti, and Kenya) with about 30 million speakers, and Afar (in Ethiopia, Eritrea and Djibouti
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https://en.wikipedia.org/wiki/Absorbing%20set
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In functional analysis and related areas of mathematics an absorbing set in a vector space is a set which can be "inflated" or "scaled up" to eventually always include any given point of the vector space.
Alternative terms are radial or absorbent set.
Every neighborhood of the origin in every topological vector space is an absorbing subset.
Definition
Notation for scalars
Suppose that is a vector space over the field of real numbers or complex numbers and for any let
denote the open ball (respectively, the closed ball) of radius in centered at
Define the product of a set of scalars with a set of vectors as and define the product of with a single vector as
Preliminaries
Balanced core and balanced hull
A subset of is said to be if for all and all scalars satisfying this condition may be written more succinctly as and it holds if and only if
Given a set the smallest balanced set containing denoted by is called the of while the largest balanced set contained within denoted by is called the of
These sets are given by the formulas
and
(these formulas show that the balanced hull and the balanced core always exist and are unique).
A set is balanced if and only if it is equal to its balanced hull () or to its balanced core (), in which case all three of these sets are equal:
If is any scalar then
while if is non-zero or if then also
One set absorbing another
If and are subsets of then is said to if it satisfies any of
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https://en.wikipedia.org/wiki/Firn
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Firn (; from Swiss German "last year's", cognate with before) is partially compacted névé, a type of snow that has been left over from past seasons and has been recrystallized into a substance denser than névé. It is ice that is at an intermediate stage between snow and glacial ice. Firn has the appearance of wet sugar, but has a hardness that makes it extremely resistant to shovelling. Its density generally ranges from 0.35 g/cm3 to 0.9 g/cm3, and it can often be found underneath the snow that accumulates at the head of a glacier.
Snowflakes are compressed under the weight of the overlying snowpack. Individual crystals near the melting point are semiliquid and slick, allowing them to glide along other crystal planes and to fill in the spaces between them, increasing the ice's density. Where the crystals touch they bond together, squeezing the air between them to the surface or into bubbles.
In the summer months, the crystal metamorphosis can occur more rapidly because of water percolation between the crystals. By summer's end, the result is firn.
The minimum altitude that firn accumulates on a glacier is called the firn limit, firn line or snowline.
List of firns
Antarctic Firn
Daniel Bruun Firn
Dreyer Firn
East Northwall Firn
Rink Firn
Sven Hedin Firn
West Northwall Firn
Other uses
In colloquial and technical language, "firn" is used to describe certain forms of old snow, including:
old snowfields, known as Firnfelder (), even if the snow is not yet one year old
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https://en.wikipedia.org/wiki/Guanosine%20monophosphate
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Guanosine monophosphate (GMP), also known as 5′-guanidylic acid or guanylic acid (conjugate base guanylate), is a nucleotide that is used as a monomer in RNA. It is an ester of phosphoric acid with the nucleoside guanosine. GMP consists of the phosphate group, the pentose sugar ribose, and the nucleobase guanine; hence it is a ribonucleoside monophosphate. Guanosine monophosphate is commercially produced by microbial fermentation.
As an acyl substituent, it takes the form of the prefix guanylyl-.
De novo synthesis
GMP synthesis starts with D-ribose 5′-phosphate, a product of the pentose phosphate pathway. The synthesis proceeds by the gradual formation of the purine ring on carbon-1 of ribose, with CO2, glutamine, glycine, aspartate and one-carbon derivatives of tetrahydrofolate donating various elements towards the building of the ring
As inhibitor of guanosine monophosphate synthesis in experimental models, the glutamine analogue DON can be used.
cGMP
GMP can also exist as a cyclic structure known as cyclic GMP. Within certain cells the enzyme guanylyl cyclase makes cGMP from GTP.
cGMP plays an important role in mediating hormonal signaling.
Sources
GMP was originally identified as the umami substance in dried shiitake mushroom. The drying process significantly increases GMP content with the breakdown of RNA. It can be found in a number of other mushrooms.
Industrial production is based on fermentation: a bacterium converts sugars into AICA ribonucleotide, which is
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https://en.wikipedia.org/wiki/Uridine%20monophosphate
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Uridine monophosphate (UMP), also known as 5′-uridylic acid (conjugate base uridylate), is a nucleotide that is used as a monomer in RNA. It is an ester of phosphoric acid with the nucleoside uridine. UMP consists of the phosphate group, the pentose sugar ribose, and the nucleobase uracil; hence, it is a ribonucleotide monophosphate. As a substituent or radical its name takes the form of the prefix uridylyl-. The deoxy form is abbreviated dUMP. Covalent attachment of UMP (e.g., to a protein such as adenylyltransferase) is called uridylylation (or sometimes uridylation).
Biosynthesis
Uridine monophosphate is formed from Orotidine 5'-monophosphate (orotidylic acid) in a decarboxylation reaction catalyzed by the enzyme orotidylate decarboxylase. Uncatalyzed, the decarboxylation reaction is extremely slow (estimated to occur on average one time per 78 million years). Adequately catalyzed, the reaction takes place once per second, an increase of 1017-fold.
In humans, the orotidylate decarboxylase function is carried out by the protein UMP synthase. Defective UMP synthase can result in orotic aciduria, a metabolic disorder.
Effects on animal intelligence
In a study, gerbils fed a combination of uridine monophosphate, choline, and docosahexaenoic acid (DHA) were found to have significantly improved performance in running mazes over those not fed the supplements, implying an increase in cognitive function.
In foods
In brain research studies, uridine monophosphate is used as a
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https://en.wikipedia.org/wiki/Cytidine%20monophosphate
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Cytidine monophosphate, also known as 5'-cytidylic acid or simply cytidylate, and abbreviated CMP, is a nucleotide that is used as a monomer in RNA. It is an ester of phosphoric acid with the nucleoside cytidine. CMP consists of the phosphate group, the pentose sugar ribose, and the nucleobase cytosine; hence, a ribonucleoside monophosphate.
As a substituent it takes the form of the prefix cytidylyl-.
Metabolism
CMP can be phosphorylated to cytidine diphosphate by the enzyme CMP kinase, with adenosine triphosphate or guanosine triphosphate donating the phosphate group. Since cytidine triphosphate is generated by amination of uridine triphosphate, the main source of CMP is from RNA being decomposed by RNAse.
See also
Deoxycytidine monophosphate
Nucleoside
Oligonucleotide
References
Nucleotides
Phosphate esters
Pyrimidones
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https://en.wikipedia.org/wiki/Human%20impact%20on%20the%20environment
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Human impact on the environment (or anthropogenic environmental impact) refers to changes to biophysical environments and to ecosystems, biodiversity, and natural resources caused directly or indirectly by humans. Modifying the environment to fit the needs of society (as in the built environment) is causing severe effects including global warming, environmental degradation (such as ocean acidification), mass extinction and biodiversity loss, ecological crisis, and ecological collapse. Some human activities that cause damage (either directly or indirectly) to the environment on a global scale include population growth, neoliberal economic policies and rapid economic growth, overconsumption, overexploitation, pollution, and deforestation. Some of the problems, including global warming and biodiversity loss, have been proposed as representing catastrophic risks to the survival of the human species.
The term anthropogenic designates an effect or object resulting from human activity. The term was first used in the technical sense by Russian geologist Alexey Pavlov, and it was first used in English by British ecologist Arthur Tansley in reference to human influences on climax plant communities. The atmospheric scientist Paul Crutzen introduced the term "Anthropocene" in the mid-1970s. The term is sometimes used in the context of pollution produced from human activity since the start of the Agricultural Revolution but also applies broadly to all major human impacts on the environme
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https://en.wikipedia.org/wiki/Hopsan
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Hopsan is a free simulation environment for fluid and mechatronic systems, developed at Linköping University. Although originally developed for simulation of fluid power systems, it has also been adopted for other domains such as electric power, flight dynamics, and vehicle dynamics. It uses bi-directional delay lines (or transmission line elements) to connect different components.
History
The development on Hopsan first began in 1977 at the Division of Hydraulics and Pneumatics at Linköping University. The first version was written in FORTRAN, with a drag-and-drop graphical user interface written in Visual Basic. In addition to the simulation capability it also had features for simulation based optimization. This used the COMPLEX direct search optimization method or a generic algorithm (GA). It also had features for frequency analysis and transfer function analysis, on simulated results. It also supported co-simulation under Simulink. Component models were written as FORTRAN subroutines. A separate tool called COMPGEN, written in Mathematica, was also developed, which can be used to generate component models in a more straightforward way. In 1991 the method of bi-directional delay lines (or transmission line modelling TLM) was introduced for system simulation.
In 2009 the development of the first version of Hopsan was dropped in favor for a brand new generation of the software, written in C++. This working name of the project is Hopsan NG, and the first beta version was re
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https://en.wikipedia.org/wiki/Neural%20network
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A neural network is a neural circuit of biological neurons, sometimes also called a biological neural network, or a network of artificial neurons or nodes in the case of an artificial neural network.
Artificial neural networks are used for solving artificial intelligence (AI) problems; they model connections of biological neurons as weights between nodes. A positive weight reflects an excitatory connection, while negative values mean inhibitory connections. All inputs are modified by a weight and summed. This activity is referred to as a linear combination. Finally, an activation function controls the amplitude of the output. For example, an acceptable range of output is usually between 0 and 1, or it could be −1 and 1.
These artificial networks may be used for predictive modeling, adaptive control and applications where they can be trained via a dataset. Self-learning resulting from experience can occur within networks, which can derive conclusions from a complex and seemingly unrelated set of information.
Overview
A biological neural network is composed of a group of chemically connected or functionally associated neurons. A single neuron may be connected to many other neurons and the total number of neurons and connections in a network may be extensive. Connections, called synapses, are usually formed from axons to dendrites, though dendrodendritic synapses and other connections are possible. Apart from electrical signalling, there are other forms of signalling that ar
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https://en.wikipedia.org/wiki/Bi-directional%20delay%20line
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In mathematics, a bi-directional delay line is a numerical analysis technique used in computer simulation for solving ordinary differential equations by converting them to hyperbolic equations. In this way an explicit solution scheme is obtained with highly robust numerical properties. It was introduced by Auslander in 1968.
It originates from simulation of hydraulic pipelines where wave propagation was studied. It was then found that it could be used as an efficient numerical technique for numerically insulating different parts of a simulation model in each times step. It is used in the HOPSAN simulation package (Krus et al. 1990).
It is also known as the Transmission Line Modelling (TLM) from an independent development by Johns and O'Brian 1980. This is also extended to partial differential equations.
References
D.M. Auslander, "Distributed System Simulation with Bilateral Delay Line Models", Journal of Basic Engineering, Trans. ASME p195-p200. June 1968.
P. B. Johns and M.O'Brien. "Use of the transmission line modelling (t.l.m) method to solve nonlinear lumped networks", The Radio Electron and Engineer. 1980.
P Krus, A Jansson, J-O Palmberg, K Weddfeldt. "Distributed Simulation of Hydromechanical Systems". Presented at Third Bath International Fluid Power Workshop, Bath, UK 1990.
Numerical differential equations
Numerical analysis
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https://en.wikipedia.org/wiki/Write%20once%2C%20compile%20anywhere
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Write once, compile anywhere (WOCA) is a philosophy taken by a compiler and its associated software libraries or by a software library/software framework which refers to a capability of writing a computer program that can be compiled on all platforms without the need to modify its source code. As opposed to Sun's write once, run anywhere slogan, cross-platform compatibility is implemented only at the source code level, rather than also at the compiled binary code level.
Introduction
There are many languages that follow the WOCA philosophy, such as C++, Pascal (see Free Pascal), Ada, Cobol, or C, on condition that they don't use functions beyond those provided by the standard library. Languages like Go go even further in as far that no system specific things are used, it should just work, and for system-specific elements a system of platform-specific files is used. A computer program may also use cross-platform libraries, which provide an abstraction layer hiding the differences between various platforms, for things like sockets and GUI, ensuring the portability of the written source code. This is, for example, supported by Qt (C++) or the Lazarus (Pascal) IDE via its LCL and corresponding widgetsets.
Today, we have very powerful desktop computers as well as computers in our phones, which often have sophisticated applications such as word processing, Database management, and spreadsheets, that can allow people with no programming experience to, sort, extract, and manipulate
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https://en.wikipedia.org/wiki/AAL1gator
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The AAL1gator is a semiconductor device that implements the Circuit Emulation Service. It was developed between 1994 and 1998 and became a run-away success. It also played a role in the acquisition of four companies. The name was based on the fact that the AAL1gator implements the ATM AAL-1 standard.
Development of the AAL1gator
The AAL1gator was developed by Network Synthesis, Inc. under contract from Integrated Telecom Technology (IgT). It was the first semiconductor solution to implement the Circuit Emulation Service standard from the ATM Forum. It implemented 8 DS1/E1 lines worth of CES and had 256 channels. It flexibly converted the PDH DS1 signal into Asynchronous Transfer Mode cells.
The AAL1gator was principally designed by the Network Synthesis CEO, Brian Holden and a consultant, Ed Lennox. Brian Holden was also involved in the ATM Forum standardization effort for the Circuit Emulation Service. Additional design efforts came from Andy Annudurai, Ravi Sajwan, and Imran Chaudhri (who also came up with the name). Chee Hu did most of the work on getting the "C" version to work at speed and to be manufacturable. Denis Smetana did most of the work on the "D" version and on the later 32 DS1 version. Jim Jacobson of OnStream Networks was the Beta Customer.
Patents on the AAL1gator
Two U.S. patents were issued on the AAL1gator's calendar-based transmit scheduler, one on the original product and an even better one on the "D" version enhancements designed by Denis
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https://en.wikipedia.org/wiki/Biphenyl
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Biphenyl (also known as diphenyl, phenylbenzene, 1,1′-biphenyl, lemonene or BP) is an organic compound that forms colorless crystals. Particularly in older literature, compounds containing the functional group consisting of biphenyl less one hydrogen (the site at which it is attached) may use the prefixes xenyl or diphenylyl.
It has a distinctively pleasant smell. Biphenyl is an aromatic hydrocarbon with a molecular formula (C6H5)2. It is notable as a starting material for the production of polychlorinated biphenyls (PCBs), which were once widely used as dielectric fluids and heat transfer agents.
Biphenyl is also an intermediate for the production of a host of other organic compounds such as emulsifiers, optical brighteners, crop protection products, and plastics. Biphenyl is insoluble in water, but soluble in typical organic solvents. The biphenyl molecule consists of two connected phenyl rings.
Properties and occurrence
Biphenyl is a solid at room temperature, with a melting point of . In the gas phase the molecule exists in two enantiomorphic twisted forms with an angle between the planes of the two rings of 44.4°. In the room-temperature solid, biphenyl is crystalline with space group P2/c, which does not allow for chiral crystals. Rather than there being a double-well potential entailing the two twisted conformations, the potential energy is minimized at zero twist.
Biphenyl occurs naturally in coal tar, crude oil, and natural gas and can be isolated from these so
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https://en.wikipedia.org/wiki/Yttrium%20aluminium%20garnet
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Yttrium aluminium garnet (YAG, Y3Al5O12) is a synthetic crystalline material of the garnet group. It is a cubic yttrium aluminium oxide phase, with other examples being YAlO3 (YAP) in a hexagonal or an orthorhombic, perovskite-like form, and the monoclinic Y4Al2O9 (YAM).
Due to its broad optical transparency, low internal stress, high hardness, chemical and heat resistance, YAG is used for a variety of optics. Its lack of birefringence (unlike sapphire) makes it an interesting material for high-energy/high-power laser systems. Laser damage levels of YAG ranged from 1.1 to 2.2 kJ/cm2 (1064 nm, 10 ns).
YAG, like garnet and sapphire, has no uses as a laser medium when pure. However, after being doped with an appropriate ion, YAG is commonly used as a host material in various solid-state lasers. Rare earth elements such as neodymium and erbium can be doped into YAG as active laser ions, yielding Nd:YAG and Er:YAG lasers, respectively. Cerium-doped YAG (Ce:YAG) is used as a phosphor in cathode ray tubes and white light-emitting diodes, and as a scintillator.
Gemstone YAG
YAG for a period was used in jewelry as a diamond and other gemstone simulant. Colored variants and their doping elements include: green (chromium), blue (cobalt), red (manganese), yellow (titanium), blue/pink/purple (neodymium, depending on light source), pink, and orange. As faceted gems they are valued (as synthetics) for their clarity, durability, high refractive index and dispersion, and occasionally prope
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https://en.wikipedia.org/wiki/Amusia
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Amusia is a musical disorder that appears mainly as a defect in processing pitch but also encompasses musical memory and recognition. Two main classifications of amusia exist: acquired amusia, which occurs as a result of brain damage, and congenital amusia, which results from a music-processing anomaly present since birth.
Studies have shown that congenital amusia is a deficit in fine-grained pitch discrimination and that 4% of the population has this disorder. Acquired amusia may take several forms. Patients with brain damage may experience the loss of ability to produce musical sounds while sparing speech, much like aphasics lose speech selectively but can sometimes still sing. Other forms of amusia may affect specific sub-processes of music processing. Current research has demonstrated dissociations between rhythm, melody, and emotional processing of music. Amusia may include impairment of any combination of these skill sets.
Signs and symptoms
Symptoms of amusia are generally categorized as receptive, clinical, or mixed. Symptoms of receptive amusia, sometimes referred to as "musical deafness" or "tone deafness", include the inability to recognize familiar melodies, the loss of ability to read musical notation, and the inability to detect wrong or out-of tune notes. Clinical, or expressive, symptoms include the loss of ability to sing, write musical notation, and/or play an instrument. A mixed disorder is a combination of expressive and receptive impairment.
Clinical s
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https://en.wikipedia.org/wiki/R%C3%A9nyi%20entropy
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In information theory, the Rényi entropy is a quantity that generalizes various notions of entropy, including Hartley entropy, Shannon entropy, collision entropy, and min-entropy. The Rényi entropy is named after Alfréd Rényi, who looked for the most general way to quantify information while preserving additivity for independent events. In the context of fractal dimension estimation, the Rényi entropy forms the basis of the concept of generalized dimensions.
The Rényi entropy is important in ecology and statistics as index of diversity. The Rényi entropy is also important in quantum information, where it can be used as a measure of entanglement. In the Heisenberg XY spin chain model, the Rényi entropy as a function of can be calculated explicitly because it is an automorphic function with respect to a particular subgroup of the modular group. In theoretical computer science, the min-entropy is used in the context of randomness extractors.
Definition
The Rényi entropy of order , where and , is defined as
It is further defined at as
Here, is a discrete random variable with possible outcomes in the set and corresponding probabilities for . The resulting unit of information is determined by the base of the logarithm, e.g. shannon for base 2, or nat for base e.
If the probabilities are for all , then all the Rényi entropies of the distribution are equal: .
In general, for all discrete random variables , is a non-increasing function in .
Applications often ex
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https://en.wikipedia.org/wiki/Restriction%20point
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The restriction point (R), also known as the Start or G1/S checkpoint, is a cell cycle checkpoint in the G1 phase of the animal cell cycle at which the cell becomes "committed" to the cell cycle, and after which extracellular signals are no longer required to stimulate proliferation. The defining biochemical feature of the restriction point is the activation of G1/S- and S-phase cyclin-CDK complexes, which in turn phosphorylate proteins that initiate DNA replication, centrosome duplication, and other early cell cycle events. It is one of three main cell cycle checkpoints, the other two being the G2-M DNA damage checkpoint and the spindle checkpoint.
History
Originally, Howard Martin Temin showed that chicken cells reach a point at which they are committed to replicate their DNA and are not dependent on extracellular signals. About 20 years later, in 1973, Arthur Pardee demonstrated that a single restriction point exists in G1. Previously, G1 had been defined simply as the time between mitosis and S phase. No molecular or morphological place-markers for a cell's position in G1 were known. Pardee used a double-block method in which he shifted cells from one cell cycle block (such as critical amino acid withdrawal or serum withdrawal) to another and compared each block's efficiency at preventing progression to S phase. He found that both blocks in all cases examined were equally efficient at blocking S phase progression, indicating that they must all act at the same point in G
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https://en.wikipedia.org/wiki/Small-signal%20model
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Small-signal modeling is a common analysis technique in electronics engineering used to approximate the behavior of electronic circuits containing nonlinear devices with linear equations. It is applicable to electronic circuits in which the AC signals (i.e., the time-varying currents and voltages in the circuit) are small relative to the DC bias currents and voltages. A small-signal model is an AC equivalent circuit in which the nonlinear circuit elements are replaced by linear elements whose values are given by the first-order (linear) approximation of their characteristic curve near the bias point.
Overview
Many of the electrical components used in simple electric circuits, such as resistors, inductors, and capacitors are linear. Circuits made with these components, called linear circuits, are governed by linear differential equations, and can be solved easily with powerful mathematical frequency domain methods such as the Laplace transform.
In contrast, many of the components that make up electronic circuits, such as diodes, transistors, integrated circuits, and vacuum tubes are nonlinear; that is the current through them is not proportional to the voltage, and the output of two-port devices like transistors is not proportional to their input. The relationship between current and voltage in them is given by a curved line on a graph, their characteristic curve (I-V curve). In general these circuits don't have simple mathematical solutions. To calculate the curr
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https://en.wikipedia.org/wiki/Expressivity%20%28genetics%29
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In genetics, expressivity is the degree to which a phenotype is expressed by individuals having a particular genotype. (Alternately, it may refer to the expression of particular gene by individuals having a certain phenotype.) Expressivity is related to the intensity of a given phenotype; it differs from penetrance, which refers to the proportion of individuals with a particular genotype that actually express the phenotype.
Variable expressivity
Variable expressivity refers to the degree in which a genotype is phenotypically expressed. For example, multiple people with the same disease can have the same genotype but one may express more severe symptoms, while another carrier may appear normal. This variation in expression can be affected by modifier genes, epigenetic factors or the environment. Modifier genes can alter the expression of other genes in either an additive or multiplicative way. Meaning the phenotype that is observed can be a result of two different alleles being summed or multiplied. However, a reduction in expression may also occur in which the primary locus, where the phenotype is expressed, is affected. Epigenetic factors, such as cis-regulatory elements, can also cause variability in expression by inducing variation in transcript abundance.
Examples
Three common syndromes that involved phenotypic variability due to expressivity include: Marfan syndrome, Van der Woude Syndrome, and neurofibromatosis.
The characteristics of Marfan syndrome widely vary a
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https://en.wikipedia.org/wiki/Federigo%20Enriques
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Abramo Giulio Umberto Federigo Enriques (5 January 1871 – 14 June 1946) was an Italian mathematician, now known principally as the first to give a classification of algebraic surfaces in birational geometry, and other contributions in algebraic geometry.
Biography
Enriques was born in Livorno, and brought up in Pisa, in a Sephardi Jewish family of Portuguese descent. His younger brother was zoologist Paolo Enriques who was also the father of Enzo Enriques Agnoletti and Anna Maria Enriques Agnoletti. He became a student of Guido Castelnuovo (who later became his brother-in-law after marrying his sister Elbina), and became an important member of the Italian school of algebraic geometry. He also worked on differential geometry. He collaborated with Castelnuovo, Corrado Segre and Francesco Severi. He had positions at the University of Bologna, and then the University of Rome La Sapienza. In 1931 he sworn allegiance to fascism, and in 1933 he became a member of the PNF. Despite this, he lost his position in 1938, when the Fascist government enacted the "leggi razziali" (racial laws), which in particular banned Jews from holding professorships in Universities.
The Enriques classification, of complex algebraic surfaces up to birational equivalence, was into five main classes, and was background to further work until Kunihiko Kodaira reconsidered the matter in the 1950s. The largest class, in some sense, was that of surfaces of general type: those for which the consideration of di
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https://en.wikipedia.org/wiki/Negamax
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Negamax search is a variant form of minimax search that relies on the zero-sum property of a two-player game.
This algorithm relies on the fact that to simplify the implementation of the minimax algorithm. More precisely, the value of a position to player A in such a game is the negation of the value to player B. Thus, the player on move looks for a move that maximizes the negation of the value resulting from the move: this successor position must by definition have been valued by the opponent. The reasoning of the previous sentence works regardless of whether A or B is on move. This means that a single procedure can be used to value both positions. This is a coding simplification over minimax, which requires that A selects the move with the maximum-valued successor while B selects the move with the minimum-valued successor.
It should not be confused with negascout, an algorithm to compute the minimax or negamax value quickly by clever use of alpha–beta pruning discovered in the 1980s. Note that alpha–beta pruning is itself a way to compute the minimax or negamax value of a position quickly by avoiding the search of certain uninteresting positions.
Most adversarial search engines are coded using some form of negamax search.
Negamax base algorithm
NegaMax operates on the same game trees as those used with the minimax search algorithm. Each node and root node in the tree are game states (such as game board configuration) of a two player game. Transitions to child nodes r
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https://en.wikipedia.org/wiki/Hamilton%E2%80%93Norwood%20scale
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The Hamilton–Norwood scale is used to classify the stages of male pattern baldness. It is one of the widely accepted and reproducible classification system for the male pattern hair loss (androgenetic alopecia). The stages are described with a number from 1 to 7 with a type A variant for the cases with anterior involvement.
Overview
Androgenetic alopecia follows a defined pattern of hair loss, beginning with bitemporal recession of the frontal hairline. Eventually, diffuse thinning over the vertex (top) of the scalp occurs. With progression, complete hair loss in this region is common. The bald patch progressively enlarges and eventually joins the receding frontal hairline.
This measurement scale was first introduced by James Hamilton in the 1950s and later revised and updated by O'Tar Norwood in the 1970s. It is sometimes referred to as the Norwood–Hamilton scale or simply the Norwood scale.
The scale is regularly used by doctors to assess the severity of baldness, but it is not considered very reliable since examiners' conclusions can vary.
Diagnostic
Dermatologists might use the Norwood Scale on patients to assess male pattern baldness. It is especially used to check if hair loss treatments are helping patients regaining hair.
References
Trichology
Medical scales
Dermatologic terminology
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https://en.wikipedia.org/wiki/Polypodiaceae
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Polypodiaceae is a family of ferns. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), the family includes around 65 genera and an estimated 1,650 species and is placed in the order Polypodiales, suborder Polypodiineae. A broader circumscription has also been used, in which the family includes other families kept separate in PPG I. Nearly all species are epiphytes, but some are terrestrial.
Description
Stems of Polypodiaceae range from erect to long-creeping. The fronds are entire, pinnatifid, or variously forked or pinnate. The petioles lack stipules. The scaly rhizomes are generally creeping in nature. Polypodiaceae species are found in wet climates, most commonly in rain forests. In temperate zones, most species tend to be epiphytic or epipetric.
Notable examples of ferns in this family include the resurrection fern (Pleopeltis polypodioides) and the golden serpent fern (Phlebodium aureum).
Taxonomy
Two distinct circumscriptions of the family are in use. The Pteridophyte Phylogeny Group classification of 2016 (PPG I) uses a circumscription of Polypodiaceae in which the family is placed in the suborder Polypodiineae (eupolypods I), along with eight other families. The relationship between the families is shown in the consensus cladogram below.
An alternative approach treats the suborder Polypodiineae as the family Polypodiaceae sensu lato, and reduces the families to subfamilies, so that the Polypodiaceae sensu stricto becomes the subfamily Polypodioide
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https://en.wikipedia.org/wiki/Barrelled%20space
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In functional analysis and related areas of mathematics, a barrelled space (also written barreled space) is a topological vector space (TVS) for which every barrelled set in the space is a neighbourhood for the zero vector.
A barrelled set or a barrel in a topological vector space is a set that is convex, balanced, absorbing, and closed.
Barrelled spaces are studied because a form of the Banach–Steinhaus theorem still holds for them.
Barrelled spaces were introduced by .
Barrels
A convex and balanced subset of a real or complex vector space is called a and it is said to be , , or .
A or a in a topological vector space (TVS) is a subset that is a closed absorbing disk; that is, a barrel is a convex, balanced, closed, and absorbing subset.
Every barrel must contain the origin. If and if is any subset of then is a convex, balanced, and absorbing set of if and only if this is all true of in for every -dimensional vector subspace thus if then the requirement that a barrel be a closed subset of is the only defining property that does not depend on (or lower)-dimensional vector subspaces of
If is any TVS then every closed convex and balanced neighborhood of the origin is necessarily a barrel in (because every neighborhood of the origin is necessarily an absorbing subset). In fact, every locally convex topological vector space has a neighborhood basis at its origin consisting entirely of barrels. However, in general, there exist barrels that are not neighb
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https://en.wikipedia.org/wiki/Barrelled%20set
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In functional analysis, a subset of a topological vector space (TVS) is called a barrel or a barrelled set if it is closed convex balanced and absorbing.
Barrelled sets play an important role in the definitions of several classes of topological vector spaces, such as barrelled spaces.
Definitions
Let be a topological vector space (TVS).
A subset of is called a if it is closed convex balanced and absorbing in
A subset of is called and a if it absorbs every bounded subset of Every bornivorous subset of is necessarily an absorbing subset of
Let be a subset of a topological vector space If is a balanced absorbing subset of and if there exists a sequence of balanced absorbing subsets of such that for all then is called a in where moreover, is said to be a(n):
if in addition every is a closed and bornivorous subset of for every
if in addition every is a closed subset of for every
if in addition every is a closed and bornivorous subset of for every
In this case, is called a for
Properties
Note that every bornivorous ultrabarrel is an ultrabarrel and that every bornivorous suprabarrel is a suprabarrel.
Examples
In a semi normed vector space the closed unit ball is a barrel.
Every locally convex topological vector space has a neighbourhood basis consisting of barrelled sets, although the space itself need not be a barreled space.
See also
References
Bibliography
Topological vector spaces
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https://en.wikipedia.org/wiki/Darboux%20basis
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A Darboux basis may refer to:
A Darboux basis of a symplectic vector space
In differential geometry, a Darboux frame on a surface
A Darboux tangent in the dovetail joint
Mathematics disambiguation pages
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https://en.wikipedia.org/wiki/Oleandra
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Oleandra is a genus of ferns. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), it is the only genus in the family Oleandraceae, which is placed in suborder Polypodiineae, order Polypodiales. Alternatively, the family may be placed in a very broadly defined family Polypodiaceae sensu lato as the subfamily Oleandroideae.
The genus contains about 15 species. Most are erect ground ferns or scandent epiphytes that start from the ground. The lamina (leafy area of the fronds) are simple or pinnate, and the individual pinnae are articulate to the rachis. The sporangia are contained in discrete round sori in a single row on either side of the midrib of the fronds.
Phylogeny
The following cladogram for the suborder Polypodiineae (eupolypods I), based on the consensus cladogram in the Pteridophyte Phylogeny Group classification of 2016 (PPG I), shows a likely phylogenetic relationship between Oleandraceae and the other families of the clade.
References
Polypodiales
Fern genera
Taxa named by Antonio José Cavanilles
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https://en.wikipedia.org/wiki/Auguste%20Bravais
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Auguste Bravais (; 23 August 1811, Annonay, Ardèche – 30 March 1863, Le Chesnay, France) was a French physicist known for his work in crystallography, the conception of Bravais lattices, and the formulation of Bravais law. Bravais also studied magnetism, the northern lights, meteorology, geobotany, phyllotaxis, astronomy, statistics and hydrography.
He studied at the Collège Stanislas in Paris before joining the École Polytechnique in 1829, where he was a classmate of groundbreaking mathematician Évariste Galois, whom Bravais actually beat in a scholastic mathematics competition. Towards the end of his studies he became a naval officer, and sailed on the Finistere in 1832 as well as the Loiret afterwards. He took part in hydrographic work along the Algerian Coast. He participated in the Recherche expedition and helped the Lilloise in Spitzbergen and Lapland.
Bravais taught a course in applied mathematics for astronomy in the Faculty of Sciences in Lyon, starting in 1840. He succeeded Victor Le Chevalier in the Chair of Physics at the Ecole Polytechnique from 1845 until 1856 when he was replaced by Henri Hureau de Sénarmont. In 1844 he published a paper on the statistical concept of correlation, and arrived at a definition of the correlation coefficient before Karl Pearson. He is, however, best remembered for his work on Bravais lattices, particularly his 1848 discovery that there are 14 unique lattices in three-dimensional crystalline systems, correcting the previous scheme
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https://en.wikipedia.org/wiki/Balanced%20set
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In linear algebra and related areas of mathematics a balanced set, circled set or disk in a vector space (over a field with an absolute value function ) is a set such that for all scalars satisfying
The balanced hull or balanced envelope of a set is the smallest balanced set containing
The balanced core of a set is the largest balanced set contained in
Balanced sets are ubiquitous in functional analysis because every neighborhood of the origin in every topological vector space (TVS) contains a balanced neighborhood of the origin and every convex neighborhood of the origin contains a balanced convex neighborhood of the origin (even if the TVS is not locally convex). This neighborhood can also be chosen to be an open set or, alternatively, a closed set.
Definition
Let be a vector space over the field of real or complex numbers.
Notation
If is a set, is a scalar, and then let and and for any let
denote, respectively, the open ball and the closed ball of radius in the scalar field centered at where and
Every balanced subset of the field is of the form or for some
Balanced set
A subset of is called a or balanced if it satisfies any of the following equivalent conditions:
Definition: for all and all scalars satisfying
for all scalars satisfying
where
For every
is a (if ) or (if ) dimensional vector subspace of
If then the above equality becomes which is exactly the previous condition for a set to be balanced. Thus, is b
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https://en.wikipedia.org/wiki/Absolutely%20convex%20set
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In mathematics, a subset C of a real or complex vector space is said to be absolutely convex or disked if it is convex and balanced (some people use the term "circled" instead of "balanced"), in which case it is called a disk.
The disked hull or the absolute convex hull of a set is the intersection of all disks containing that set.
Definition
A subset of a real or complex vector space is called a and is said to be , , and if any of the following equivalent conditions is satisfied:
is a convex and balanced set.
for any scalars and if then
for all scalars and if then
for any scalars and if then
for any scalars if then
The smallest convex (respectively, balanced) subset of containing a given set is called the convex hull (respectively, the balanced hull) of that set and is denoted by (respectively, ).
Similarly, the , the , and the of a set is defined to be the smallest disk (with respect to subset inclusion) containing
The disked hull of will be denoted by or and it is equal to each of the following sets:
which is the convex hull of the balanced hull of ; thus,
In general, is possible, even in finite dimensional vector spaces.
the intersection of all disks containing
Sufficient conditions
The intersection of arbitrarily many absolutely convex sets is again absolutely convex; however, unions of absolutely convex sets need not be absolutely convex anymore.
If is a disk in then is absorbing in if and only if
Properties
If is a
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https://en.wikipedia.org/wiki/Methylcyclopropane
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Methylcyclopropane is an organic compound with the structural formula C3H5CH3. This colorless gas is the monomethyl derivative of cyclopropane.
Reactions
Methylcyclopropane, like many other cyclopropanes, undergoes ring-opening reactions. Bond cleavage in certain reactions is also reported in conjunction with the use of methylenecyclopropane groups as protective groups for amines.
References
Cyclopropyl compounds
Hydrocarbons
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https://en.wikipedia.org/wiki/Zendmast%20Ruiselede
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The Zendmasts of Ruiselede were eight high guyed radio masts at Ruiselede, Belgium, built in 1923 for carrying an aerial for VLF transmission (nominal frequency 16.2 kHz). On 30 December 1933, an Imperial Airways aircraft crashed into a mast and demolished it. Most of the masts were blown up by German troops in October 1940.
The masts were designed by the Belgian engineer Arthur Vierendeel.
External links
http://www.zenitel.biz/CSS/02_about_us/2_history/pdf/BoekSait_Ne_Fr.pdf
http://www.mil.be/vox/subject/index.asp?LAN=fr&ID=525&MENU=735&PAGE=2
http://www.seefunker.de/homepage/belgien5.htm
https://web.archive.org/web/20050219143733/http://users.skynet.be/dezande/radio.htm
http://users.telenet.be/karel.roose/vierendeel/structuren.html
Radio masts and towers in Europe
Buildings and structures in West Flanders
Towers in Belgium
Demolished buildings and structures in Belgium
Buildings and structures demolished in 1940
Towers completed in 1923
1923 establishments in Belgium
1940 disestablishments in Belgium
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https://en.wikipedia.org/wiki/Lenstra%E2%80%93Lenstra%E2%80%93Lov%C3%A1sz%20lattice%20basis%20reduction%20algorithm
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The Lenstra–Lenstra–Lovász (LLL) lattice basis reduction algorithm is a polynomial time lattice reduction algorithm invented by Arjen Lenstra, Hendrik Lenstra and László Lovász in 1982. Given a basis with n-dimensional integer coordinates, for a lattice L (a discrete subgroup of Rn) with , the LLL algorithm calculates an LLL-reduced (short, nearly orthogonal) lattice basis in time where is the largest length of under the Euclidean norm, that is, .
The original applications were to give polynomial-time algorithms for factorizing polynomials with rational coefficients, for finding simultaneous rational approximations to real numbers, and for solving the integer linear programming problem in fixed dimensions.
LLL reduction
The precise definition of LLL-reduced is as follows: Given a basis
define its Gram–Schmidt process orthogonal basis
and the Gram-Schmidt coefficients
for any .
Then the basis is LLL-reduced if there exists a parameter in such that the following holds:
(size-reduced) For . By definition, this property guarantees the length reduction of the ordered basis.
(Lovász condition) For k = 2,3,..,n .
Here, estimating the value of the parameter, we can conclude how well the basis is reduced. Greater values of lead to stronger reductions of the basis. Initially, A. Lenstra, H. Lenstra and L. Lovász demonstrated the LLL-reduction algorithm for . Note that although LLL-reduction is well-defined for , the polynomial-time complexity is guaranteed only for
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https://en.wikipedia.org/wiki/Cross-entropy
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In information theory, the cross-entropy between two probability distributions and over the same underlying set of events measures the average number of bits needed to identify an event drawn from the set if a coding scheme used for the set is optimized for an estimated probability distribution , rather than the true distribution .
Definition
The cross-entropy of the distribution relative to a distribution over a given set is defined as follows:
,
where is the expected value operator with respect to the distribution .
The definition may be formulated using the Kullback–Leibler divergence , divergence of from (also known as the relative entropy of with respect to ).
where is the entropy of .
For discrete probability distributions and with the same support this means
The situation for continuous distributions is analogous. We have to assume that and are absolutely continuous with respect to some reference measure (usually is a Lebesgue measure on a Borel σ-algebra). Let and be probability density functions of and with respect to . Then
and therefore
NB: The notation is also used for a different concept, the joint entropy of and .
Motivation
In information theory, the Kraft–McMillan theorem establishes that any directly decodable coding scheme for coding a message to identify one value out of a set of possibilities can be seen as representing an implicit probability distribution over , where is the length of the code for in bits. Therefor
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https://en.wikipedia.org/wiki/Langerhans%20cell%20histiocytosis
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Langerhans cell histiocytosis (LCH) is an abnormal clonal proliferation of Langerhans cells, abnormal cells deriving from bone marrow and capable of migrating from skin to lymph nodes.
Symptoms range from isolated bone lesions to multisystem disease. LCH is part of a group of syndromes called histiocytoses, which are characterized by an abnormal proliferation of histiocytes (an archaic term for activated dendritic cells and macrophages). These diseases are related to other forms of abnormal proliferation of white blood cells, such as leukemias and lymphomas.
The disease has gone by several names, including Hand–Schüller–Christian disease, Abt-Letterer-Siwe disease, Hashimoto-Pritzker disease (a very rare self-limiting variant seen at birth) and histiocytosis X, until it was renamed in 1985 by the Histiocyte Society.
Classification
The disease spectrum results from clonal accumulation and proliferation of cells resembling the epidermal dendritic cells called Langerhans cells, sometimes called dendritic cell histiocytosis. These cells in combination with lymphocytes, eosinophils, and normal histiocytes form typical LCH lesions that can be found in almost any organ. A similar set of diseases has been described in canine histiocytic diseases.
LCH is clinically divided into three groups: unifocal, multifocal unisystem, and multifocal multisystem.
Unifocal
Unifocal LCH, also called eosinophilic granuloma (an older term which is now known to be a misnomer), is a disease charac
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https://en.wikipedia.org/wiki/Hydrops%20fetalis
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Hydrops fetalis or hydrops foetalis is a condition in the fetus characterized by an accumulation of fluid, or edema, in at least two fetal compartments. By comparison, hydrops allantois or hydrops amnion is an accumulation of excessive fluid in the allantoic or amniotic space, respectively.
Signs and symptoms
Locations can include the subcutaneous tissue on the scalp, the pleura (pleural effusion), the pericardium (pericardial effusion) and the abdomen (ascites). Edema is usually seen in the fetal subcutaneous tissue, sometimes leading to spontaneous abortion. It is a prenatal form of heart failure, in which the heart is unable to satisfy demand (in most cases abnormally high) for blood flow.
Causes
Hydrops fetalis usually stems from fetal anemia, when the heart needs to pump a much greater volume of blood to deliver the same amount of oxygen. This anemia can have either an immune or non-immune cause. Non-immune hydrops can also be unrelated to anemia, for example if a fetal tumor or congenital cystic adenomatoid malformation increases the demand for blood flow. The increased demand for cardiac output leads to heart failure, and corresponding edema.
Immune pathophysiology
Erythroblastosis fetalis, also known as Rh disease, is the only immune cause of hydrops fetalis. Rh disease is a hemolytic disease of newborns. Pregnant mothers do not always have the same blood type as their child. During birth or throughout the pregnancy, the mother may be exposed to the infant's bl
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https://en.wikipedia.org/wiki/Invertase
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β-Fructofuranosidase is an enzyme that catalyzes the hydrolysis (breakdown) of the table sugar sucrose into fructose and glucose. Alternative names for β-fructofuranosidase include invertase, saccharase, glucosucrase, β-fructosidase, invertin, sucrase, fructosylinvertase, alkaline invertase, acid invertase, and the systematic name: β-fructofuranosidase. The resulting mixture of fructose and glucose is called inverted sugar syrup. Related to invertases are sucrases. Invertases and sucrases hydrolyze sucrose to give the same mixture of glucose and fructose. Invertase is a glycoprotein that hydrolyses (cleaves) the non-reducing terminal β-fructofuranoside residues. Invertases cleave the O-C(fructose) bond, whereas the sucrases cleave the O-C(glucose) bond. Invertase cleaves the α-1,2-glycosidic bond of sucrose.
For industrial use, invertase is usually derived from yeast. It is also synthesized by bees, which use it to make honey from nectar. Optimal temperature at which the rate of reaction is at its greatest is 60 °C and an optimum pH of 4.5. Typically, sugar is inverted with sulfuric acid.
Invertase is produced by various organisms like yeast, fungi, bacteria, higher plants, and animals. For example: Saccharomyces cerevisiae, Saccharomyces carlsbergensis, S. pombe, Aspergillus spp, Penicillium chrysogenum, Azotobacter spp, Lactobacillus spp, Pseudomonas spp etc.
Applications and examples
Invertase is used to produce inverted sugar syrup.
Invertase is expensive, so it m
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https://en.wikipedia.org/wiki/Nasal%20congestion
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Nasal congestion is the partial or complete blockage of nasal passages, leading to impaired nasal breathing, usually due to membranes lining the nose becoming swollen from inflammation of blood vessels.
Background
In about 85% of cases, nasal congestion leads to mouth breathing rather than nasal breathing. According to Jason Turowski, MD of the Cleveland Clinic, "we are designed to breathe through our noses from birth—it's the way humans have evolved." This is referred to as "obligate nasal breathing."
Nasal congestion can interfere with hearing and speech. Significant congestion may interfere with sleep, cause snoring, and can be associated with sleep apnea or upper airway resistance syndrome. In children, nasal congestion from enlarged adenoids has caused chronic sleep apnea with insufficient oxygen levels and hypoxia. The problem usually resolves after surgery to remove the adenoids and tonsils, however the problem often relapses later in life due to craniofacial alterations from chronic nasal congestion.
Causes
Allergies, like hay fever, allergic reaction to pollen or grass
Common cold, influenza or COVID-19
Rhinitis medicamentosa, a condition of rebound nasal congestion brought on by extended use of topical decongestants (e.g., oxymetazoline, phenylephrine, xylometazoline, and naphazoline nasal sprays)
Sinusitis or sinus infection
Narrow or collapsing nasal valve
Pregnancy may cause women to suffer from nasal congestion due to the increased amount of blood flo
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https://en.wikipedia.org/wiki/LowFER
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LowFER (Low-Frequency Experimental Radio) refers to experimental radio communication practiced by hobbyists on frequencies below 300 kHz, a part of the radio spectrum known as low frequency. The practitioners are known as "LowFERs".
Practices
LowFER operation is practiced in the United States and Canada on radio frequencies between 160 kHz and 190 kHz which is sometimes referred to as the 1750-meter band, and in the past as the 1875-meter band. In much of the world, including the U.S., there is an adjacent amateur radio band at 136–138 kHz with a number of U.S. amateur radio operators authorized to transmit on that band (notification and lack of objection from power utilities is required).
Radio operators who conduct low-frequency experimental operations on the LowFER band are known as LowFERs (pronounced "loafers"). Many LowFERs are also licensed radio amateurs, although an amateur radio license is not required for LowFER communications in those countries in Region 2, as long as the power is below a nationally prescribed limit, often 1 W.
Equipment
Practical antennas at these frequencies are much shorter than the wavelength, making it difficult to efficiently radiate much useful power. By current U.S. and Canadian regulations, LowFER transmitters may not have antenna and feed line lengths longer than , or final RF stage input powers that exceeds 1 watt. Telegraphy and digital modes are the most commonly used for communications, but speech transmission via amplitude modu
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https://en.wikipedia.org/wiki/Serotonergic
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A serotonergic substance, medication, or receptor protein is one that affects neurotransmission pathways that involve serotonin, as follows:
Serotonergic drugs
Serotonin receptor agonists
Serotonin receptor antagonists
Serotonin reuptake inhibitors
Serotonin releasing agents
Serotonergic psychedelics
Serotonergic cells
Serotonergic cell groups
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https://en.wikipedia.org/wiki/Pok
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Pok or POK may refer to:
Pakistan-occupied Kashmir, the name used by India for the portion of Kashmir under Pakistani administration
Pantoate kinase or PoK, an enzyme
P.O.K. (Podosfairikes Omades Kentrou), a former coalition of football teams of Athens
Pok (genus), a Hungarian medieval clan
Pok, a character in the Pok & Mok animated series
Pok, a dialect of the Sabaot language of Kenya
Pok, Malaysia, a settlement in Sarawak, Malaysia
Pokesdown railway station's station code
Prophecy of Kings, an expansion to the 2017 board game Twilight Imperium: Fourth Edition
People with the surname
Pok Shau-fu (1909–2000), Hong Kong journalist
Pál Pók (1929–1982), Hungarian water polo player
See also
Poc (disambiguation)
Pock
Pokémon
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https://en.wikipedia.org/wiki/Jeanne%20Coyne
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Jeanne Coyne (February 28, 1923 – May 10, 1973) was an American Broadway dancer, choreographer and actress.
Biography
With Carol Haney (1924 – 1964), Coyne assisted directors Stanley Donen and Gene Kelly, both of whom she married. She appeared as a dancer in the MGM films Words and Music, On the Town, Summer Stock, Singin' in the Rain and Kiss Me Kate.
She was married to Donen from 1948 to 1951, and to Kelly from 1960 to 1973. She and Kelly had two children, Timothy and Bridget.
She died on May 10, 1973, in Los Angeles, California, from leukemia, at the age of 50.
Filmography
References
External links
American choreographers
American stage actresses
American female dancers
Actresses from Pittsburgh
Dancers from Pennsylvania
Deaths from leukemia
1923 births
1973 deaths
Deaths from cancer in California
20th-century American actresses
20th-century American singers
20th-century American dancers
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https://en.wikipedia.org/wiki/Root%20hair
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Root hair, or absorbent hairs, are outgrowths of epidermal cells, specialized cells at the tip of a plant root. They are lateral extensions of a single cell and are only rarely branched. They are found in the region of maturation, of the root. Root hair cells improve plant water absorption by increasing root surface area to volume ratio which allows the root hair cell to take in more water. The large vacuole inside root hair cells makes this intake much more efficient. Root hairs are also important for nutrient uptake as they are main interface between plants and mycorrhizal fungi.
Function
The function of all root hairs is to collect water and mineral nutrients in the soil to be sent throughout the plant. In roots, most water absorption happens through the root hairs. The length of root hairs allows them to penetrate between soil particles and prevents harmful bacterial organisms from entering the plant through the xylem vessels. Increasing the surface area of these hairs makes plants more efficient in absorbing nutrients and interacting with microbes. As root hair cells do not carry out photosynthesis, they do not contain chloroplasts.
Importance
Root hairs form an important surface as they are needed to absorb most of the water and nutrients needed for the plant. They are also directly involved in the formation of root nodules in legume plants. The root hairs curl around the bacteria, which allows for the formation of an infection thread into the dividing cortical cells
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https://en.wikipedia.org/wiki/Pareve
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In kashrut, the dietary laws of Judaism, pareve (from for "neutral", in Hebrew , and also parve and other variant English spellings) is a classification of edible substances that contain neither dairy nor meat ingredients. Food in this category includes all items that grow from the ground (fruits, vegetables, grains, etc.), fish (only Kosher fish), eggs, and non-biological edible items (such as water and salt).
Kashrut forbids consuming mixtures of milk and meat, consuming milk and meat at the same meal, consuming dairy foods within a period of time after consuming meat (the period varies by custom), and using the same dishes for both dairy and meat. Pareve foods, being neutral, can be consumed with either dairy or meat.
Laws
Eggs that have been laid are considered pareve because they are separate from the animal. But eggs found inside a bird after its slaughter are considered to be part of the animal and therefore have the status of meat. Commercially marketed eggs generally are not taken from slaughtered animals and therefore are pareve.
Kashrut requires that common bread must be made pareve, because bread is a staple food, and there is a strong chance one may forget that the bread contains dairy or meat ingredients. Bread need not be made pareve if it is made in an unusual shape or consumed on the same day it is made. Even vegetarians are required to refrain from baking non-pareve bread because kashrut applies equally to all Jews.
Food that contains only pareve ingred
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https://en.wikipedia.org/wiki/Degree%20of%20parallelism
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The degree of parallelism (DOP) is a metric which indicates how many operations can be or are being simultaneously executed by a computer. It is used as an indicator of the complexity of algorithms, and is especially useful for describing the performance of parallel programs and multi-processor systems.
A program running on a parallel computer may utilize different numbers of processors at different times. For each time period, the number of processors used to execute a program is defined as the degree of parallelism. The plot of the DOP as a function of time for a given program is called the parallelism profile.
See also
Optical Multi-Tree with Shuffle Exchange
References
Instruction processing
Parallel computing
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https://en.wikipedia.org/wiki/Serial%20analysis%20of%20gene%20expression
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Serial Analysis of Gene Expression (SAGE) is a transcriptomic technique used by molecular biologists to produce a snapshot of the messenger RNA population in a sample of interest in the form of small tags that correspond to fragments of those transcripts. Several variants have been developed since, most notably a more robust version, LongSAGE, RL-SAGE and the most recent SuperSAGE. Many of these have improved the technique with the capture of longer tags, enabling more confident identification of a source gene.
Overview
Briefly, SAGE experiments proceed as follows:
The mRNA of an input sample (e.g. a tumour) is isolated and a reverse transcriptase and biotinylated primers are used to synthesize cDNA from mRNA.
The cDNA is bound to Streptavidin beads via interaction with the biotin attached to the primers, and is then cleaved using a restriction endonuclease called an anchoring enzyme (AE). The location of the cleavage site and thus the length of the remaining cDNA bound to the bead will vary for each individual cDNA (mRNA).
The cleaved cDNA downstream from the cleavage site is then discarded, and the remaining immobile cDNA fragments upstream from cleavage sites are divided in half and exposed to one of two adaptor oligonucleotides (A or B) containing several components in the following order upstream from the attachment site: 1) Sticky ends with the AE cut site to allow for attachment to cleaved cDNA; 2) A recognition site for a restriction endonuclease known as the
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https://en.wikipedia.org/wiki/PLAB
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PLAB or Plab may refer to:
Science and technology
GDF15 (Growth/differentiation factor 15), a protein
Photronics Inc (NASDAQ: PLAB), an American semiconductor photomask manufacturer
Phospholipase A
Professional and Linguistic Assessments Board, a UK medical test
Other uses
Pimsleur Language Aptitude Battery, a foreign language test
Paya Lebar Air Base, a military airbase in Singapore
Darrin Plab (born 1970), retired American high jumper
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https://en.wikipedia.org/wiki/Protein%20toxicity
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Protein toxicity is the effect of the buildup of protein metabolic waste compounds, like urea, uric acid, ammonia, and creatinine. Protein toxicity has many causes, including urea cycle disorders, genetic mutations, excessive protein intake, and insufficient kidney function, such as chronic kidney disease and acute kidney injury. Symptoms of protein toxicity include unexplained vomiting and loss of appetite. Untreated protein toxicity can lead to serious complications such as seizures, encephalopathy, further kidney damage, and even death.
Definition
Protein toxicity occurs when protein metabolic wastes build up in the body. During protein metabolism, nitrogenous wastes such as urea, uric acid, ammonia, and creatinine are produced. These compounds are not utilized by the human body and are usually excreted by the kidney. However, due to conditions such as renal insufficiency, the under-functioning kidney is unable to excrete these metabolic wastes, causing them to accumulate in the body and lead to toxicity. Although there are many causes of protein toxicity, this condition is most prevalent in people with chronic kidney disease who consumes a protein-rich diet, specifically, proteins from animal sources that are rapidly digested and metabolized, causing the release of a high concentration of protein metabolic wastes in the blood stream rapidly.
Causes and pathophysiology
Protein toxicity has a significant role in neurodegenerative diseases. Whether it is due to high prot
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https://en.wikipedia.org/wiki/Dispersion%20%28water%20waves%29
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In fluid dynamics, dispersion of water waves generally refers to frequency dispersion, which means that waves of different wavelengths travel at different phase speeds. Water waves, in this context, are waves propagating on the water surface, with gravity and surface tension as the restoring forces. As a result, water with a free surface is generally considered to be a dispersive medium.
For a certain water depth, surface gravity waves – i.e. waves occurring at the air–water interface and gravity as the only force restoring it to flatness – propagate faster with increasing wavelength. On the other hand, for a given (fixed) wavelength, gravity waves in deeper water have a larger phase speed than in shallower water. In contrast with the behavior of gravity waves, capillary waves (i.e. only forced by surface tension) propagate faster for shorter wavelengths.
Besides frequency dispersion, water waves also exhibit amplitude dispersion. This is a nonlinear effect, by which waves of larger amplitude have a different phase speed from small-amplitude waves.
Frequency dispersion for surface gravity waves
This section is about frequency dispersion for waves on a fluid layer forced by gravity, and according to linear theory. For surface tension effects on frequency dispersion, see surface tension effects in Airy wave theory and capillary wave.
Wave propagation and dispersion
The simplest propagating wave of unchanging form is a sine wave. A sine wave with water surface elevation η(
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https://en.wikipedia.org/wiki/Trends%20%28journals%29
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Trends is a series of 16 review journals in a range of areas of biology and chemistry published under its Cell Press imprint by Elsevier. The publisher in lieu is Danielle Loughlin.
The Trends series was established in 1976 with Trends in Biochemical Sciences, rapidly followed by Trends in Neurosciences, Trends in Pharmacological Sciences, and Immunology Today.
Immunology Today, Parasitology Today, and Molecular Medicine Today changed their names to Trends in... in 2001. Drug Discovery Today was spun off as an independent brand.
Titles
The current set of Trends journals are all published monthly:
References
External links
Academic journal series
Cell Press academic journals
English-language journals
Monthly journals
Academic journals established in 1976
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https://en.wikipedia.org/wiki/Transfer%20length%20method
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The Transfer Length Method or the "Transmission Line Model" (both abbreviated as TLM) is a technique used in semiconductor physics and engineering to determine the specific contact resistivity between a metal and a semiconductor. TLM has been developed because with the ongoing device shrinkage in microelectronics the relative contribution of the contact resistance at metal-semiconductor interfaces in a device could not be neglected any more and an accurate measurement method for determining the specific contact resistivity was required.
General description
The goal of the transfer length method (TLM) is the determination of the specific contact resistivity of a metal-semiconductor junction. To create a metal-semiconductor junction a metal film is deposited on the surface of a semiconductor substrate. The TLM is usually used to determine the specific contact resistivity when the metal-semiconductor junction shows ohmic behaviour. In this case the contact resistivity can be defined as the voltage difference across the interfacial layer between the deposited metal and the semiconductor substrate divided by the current density which is defined as the current divided by the interfacial area through which the current is passing:
In this definition of the specific contact resistivity refers to the voltage value just below the metal-semiconductor interfacial layer while represents the voltage value just above the metal-semiconductor interfacial layer. There are two differen
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https://en.wikipedia.org/wiki/Duplication
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Duplication, duplicate, and duplicator may refer to:
Biology and genetics
Gene duplication, a process which can result in free mutation
Chromosomal duplication, which can cause Bloom and Rett syndrome
Polyploidy, a phenomenon also known as ancient genome duplication
Enteric duplication cysts, certain portions of the gastrointestinal tract
Diprosopus, a form of cojoined twins also known as craniofacial duplication
Diphallia, a medical condition also known as penile duplication
Computing
Duplicate code, a source code sequence that occurs more than once in a program
Duplicate characters in Unicode, pairs of single Unicode code points that are canonically equivalent. The reason for this are compatibility issues with legacy systems
Data redundancy, either wanted or unwanted (in which case one resorts to data deduplication)
Content copying through cut, copy, and paste
File copying
Mathematics
Duplication matrix, a linear transformation dealing with half-vectorization
Doubling the cube, a problem in geometry also known as duplication of the cube
A type of multiplication theorem called the Legendre duplication formula or simply "duplication formula"
Technology
Duplicating machines, machines and processes designed to reproduce printed material, photocopying being among the best-known today; see also List of duplicating processes
Loop bin duplicator, a device designed to copy pre-recorded audio tapes
Double track, a method of railway design also known as track
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https://en.wikipedia.org/wiki/SONIC%20%28Ethernet%20controller%29
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SONIC (System-Oriented Network Interface Controller) DP83932 is a National Semiconductor 10 Mbit/s Ethernet controller. In the early 1990s, integrated ethernet subsystems based on the SONIC controller were used in computer workstations such as the MIPS Magnum family and the Olivetti M700, inter alia.
External links
SONIC documentation
Networking hardware
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https://en.wikipedia.org/wiki/Delta-sigma%20modulation
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Delta-sigma (ΔΣ; or sigma-delta, ΣΔ) modulation is an oversampling method for encoding signals into low bit depth digital signals at a very high sample-frequency as part of the process of delta-sigma analog-to-digital converters (ADCs) and digital-to-analog converters (DACs). Delta-sigma modulation achieves high quality by utilizing a negative feedback loop during quantization to the lower bit depth that continuously corrects quantization errors and moves quantization noise to higher frequencies well above the original signal's bandwidth. Subsequent low-pass filtering for demodulation easily removes this high frequency noise and time averages to achieve high accuracy in amplitude.
Both ADCs and DACs can employ delta-sigma modulation. A delta-sigma ADC (e.g. Figure 1 top) encodes an analog signal using high-frequency delta-sigma modulation and then applies a digital filter to demodulate it to a high-bit digital output at a lower sampling-frequency. A delta-sigma DAC (e.g. Figure 1 bottom) encodes a high-resolution digital input signal into a lower-resolution but higher sample-frequency signal that may then be mapped to voltages and smoothed with an analog filter for demodulation. In both cases, the temporary use of a low bit depth signal at a higher sampling frequency simplifies circuit design and takes advantage of the efficiency and high accuracy in time of digital electronics.
Primarily because of its cost efficiency and reduced circuit complexity, this technique has foun
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https://en.wikipedia.org/wiki/Oxygen-evolving%20complex
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The oxygen-evolving complex (OEC), also known as the water-splitting complex, is a water-oxidizing enzyme involved in the photo-oxidation of water during the light reactions of photosynthesis. OEC is surrounded by 4 core proteins of photosystem II at the membrane-lumen interface. The mechanism for splitting water involves absorption of three photons before the fourth provides sufficient energy for water oxidation. Based on a widely accepted theory from 1970 by Kok, the complex can exist in 5 states, denoted S0 to S4, with S0 the most reduced and S4 the most oxidized. Photons trapped by photosystem II move the system from state S0 to S4. S4 is unstable and reacts with water producing free oxygen. For the complex to reset to the lowest state, S0, it uses 2 water molecules to pull out 4 electrons.
The OEC active site contains a cluster of manganese and calcium, with the formula Mn4Ca1OxCl1–2(HCO3)y. This cluster is coordinated by D1 and CP43 subunits and stabilized by peripheral membrane proteins. Other characteristics of it have been reviewed.
Currently, the mechanism of the complex is not completely understood. Along with the role of Ca+2, Cl−1, and the membrane proteins surrounding the metal cluster not being well understood. Much of what is known has been collected from flash photolysis experiments, electron paramagnetic resonance (EPR), and X-ray spectroscopy.
References
Photosynthesis
Light reactions
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https://en.wikipedia.org/wiki/Multigrid%20method
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In numerical analysis, a multigrid method (MG method) is an algorithm for solving differential equations using a hierarchy of discretizations. They are an example of a class of techniques called multiresolution methods, very useful in problems exhibiting multiple scales of behavior. For example, many basic relaxation methods exhibit different rates of convergence for short- and long-wavelength components, suggesting these different scales be treated differently, as in a Fourier analysis approach to multigrid. MG methods can be used as solvers as well as preconditioners.
The main idea of multigrid is to accelerate the convergence of a basic iterative method (known as relaxation, which generally reduces short-wavelength error) by a global correction of the fine grid solution approximation from time to time, accomplished by solving a coarse problem. The coarse problem, while cheaper to solve, is similar to the fine grid problem in that it also has short- and long-wavelength errors. It can also be solved by a combination of relaxation and appeal to still coarser grids. This recursive process is repeated until a grid is reached where the cost of direct solution there is negligible compared to the cost of one relaxation sweep on the fine grid. This multigrid cycle typically reduces all error components by a fixed amount bounded well below one, independent of the fine grid mesh size. The typical application for multigrid is in the numerical solution of elliptic partial differential
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https://en.wikipedia.org/wiki/Gene%20amplification
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Gene amplification refers to a number of natural and artificial processes by which the number of copies of a gene is increased "without a proportional increase in other genes".
Artificial DNA amplification
In research or diagnosis DNA amplification can be conducted through methods such as:
Polymerase chain reaction, an easy, cheap, and reliable way to repeatedly replicate a focused segment of DNA by polymerizing nucleotides, a concept which is applicable to numerous fields in modern biology and related sciences.
Ligase chain reaction, a method that amplifies the nucleic acid used as the probe. For each of the two DNA strands, two partial probes are ligated to form the actual one; thus, LCR uses two enzymes: a DNA polymerase (used for initial template amplification and then inactivated) and a thermostable DNA ligase.
Transcription-mediated amplification, an isothermal, single-tube nucleic acid amplification system utilizing two enzymes, RNA polymerase and reverse transcriptase, to rapidly amplify the target RNA/DNA, enabling the simultaneous detection of multiple pathogenic organisms in a single tube.
Natural DNA amplification
DNA replication is a natural form of copying DNA with the amount of genes remaining constant. However, the amount of DNA or the number of genes can also increase within an organism through gene duplication, a major mechanism through which new genetic material is generated during molecular evolution. Common sources of gene duplications include ect
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https://en.wikipedia.org/wiki/Cell%20junction
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Cell junctions or junctional complexes, are a class of cellular structures consisting of multiprotein complexes that provide contact or adhesion between neighboring cells or between a cell and the extracellular matrix in animals. They also maintain the paracellular barrier of epithelia and control paracellular transport. Cell junctions are especially abundant in epithelial tissues. Combined with cell adhesion molecules and extracellular matrix, cell junctions help hold animal cells together.
Cell junctions are also especially important in enabling communication between neighboring cells via specialized protein complexes called communicating (gap) junctions. Cell junctions are also important in reducing stress placed upon cells.
In plants, similar communication channels are known as plasmodesmata, and in fungi they are called septal pores.
Types
In vertebrates, there are three major types of cell junction:
Adherens junctions, desmosomes and hemidesmosomes (anchoring junctions)
Gap junctions (communicating junction)
Tight junctions (occluding junctions)
Invertebrates have several other types of specific junctions, for example septate junctions or the C. elegans apical junction. In multicellular plants, the structural functions of cell junctions are instead provided for by cell walls. The analogues of communicative cell junctions in plants are called plasmodesmata.
Anchoring junctions
Cells within tissues and organs must be anchored to one another and attached to componen
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https://en.wikipedia.org/wiki/The%20Killers%20%281964%20film%29
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The Killers (released in the UK as Ernest Hemingway's "The Killers") is a 1964 American neo noir crime film. Written by Gene L. Coon and directed by Don Siegel, it is the second Hollywood adaptation of Ernest Hemingway's 1927 short story of the same name, following the 1946 version.
The film stars Lee Marvin, John Cassavetes, Angie Dickinson, and Ronald Reagan in his final film role before retiring from acting in 1966 in order to enter politics.
At the time of release, Marvin said that it was his favorite film. The supporting cast features Clu Gulager, Claude Akins, and Norman Fell. In July 2018, it was selected to be screened in the Venice Classics section at the 75th Venice International Film Festival.
Plot
Hitmen Charlie and Lee enter a school for the blind and shoot the unresistant Johnny North multiple times, killing him. Charlie is bothered that North refused to flee and notes they were paid an unusually high fee. He and Lee run through what they know about Johnny. He was once a champion race car driver whose career ended in a violent crash. Four years before his death, he was involved in a million-dollar robbery of a mail truck. Tempted by the missing money, Charlie and Lee visit Miami to interview Johnny's former mechanic, Earl Sylvester.
Earl tells them (in a flashback) Johnny was at the top of his profession when he met Sheila Farr. Johnny fell in love and planned to propose marriage. However, Johnny's career ended with a fiery crash. At the hospital, Earl revea
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https://en.wikipedia.org/wiki/Karl%20Friedrich%20August%20Rammelsberg
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Karl Friedrich August Rammelsberg (1 April 1813 – 28 December 1899) was a German mineralogist from Berlin, Prussia.
Life
After an apprenticeship in pharmacy, he studied chemistry and crystallography at the University of Berlin, where his influences were Eilhard Mitscherlich, Heinrich Rose, Christian Samuel Weiss and Gustav Rose. His graduate thesis in 1837 dealt with cyanogen, "De cyanogenii connubiis nonnullis". In 1841 he became a privatdozent at the university, and in 1845 was named an associate professor of inorganic chemistry. From 1850 he taught classes at the Gewerbeakademie, a vocational training academy that was a predecessor of the Technical University of Berlin. In 1874 he became a full professor of chemistry at the university and in 1883 was appointed director of the inorganic chemistry laboratory.
He distinguished himself with research in the fields of mineralogy, crystallography, analytical chemistry and metallurgy. He discovered the reducing action of hypophosphoric and phosphoric acids, and was the first scientist to determine the composition of Schlippe's salt (sodium thioantimonate). In addition, he made significant contributions in research involving isomorphism. He was the first scientist other than Mendeleyev to include his Periodic Table in a book, the fourth edition (1874) of Grundriss der chemie gemäss den neueren Ansichten, published in Berlin.
He described the minerals, magnesioferrite and tachyhydrite. Rammelsbergite, a nickel arsenide mineral,
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https://en.wikipedia.org/wiki/List%20of%20finite%20simple%20groups
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In mathematics, the classification of finite simple groups states that every finite simple group is cyclic, or alternating, or in one of 16 families of groups of Lie type, or one of 26 sporadic groups.
The list below gives all finite simple groups, together with their order, the size of the Schur multiplier, the size of the outer automorphism group, usually some small representations, and lists of all duplicates.
Summary
The following table is a complete list of the 18 families of finite simple groups and the 26 sporadic simple groups, along with their orders. Any non-simple members of each family are listed, as well as any members duplicated within a family or between families. (In removing duplicates it is useful to note that no two finite simple groups have the same order, except that the group A8 = A3(2) and A2(4) both have order 20160, and that the group Bn(q) has the same order as Cn(q) for q odd, n > 2. The smallest of the latter pairs of groups are B3(3) and C3(3) which both have order 4585351680.)
There is an unfortunate conflict between the notations for the alternating groups An and the groups of Lie type An(q). Some authors use various different fonts for An to distinguish them. In particular,
in this article we make the distinction by setting the alternating groups An in Roman font and the Lie-type groups An(q) in italic.
In what follows, n is a positive integer, and q is a positive power of a prime number p, with the restrictions noted. The notation (a,
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https://en.wikipedia.org/wiki/Rayleigh%E2%80%93Taylor%20instability
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The Rayleigh–Taylor instability, or RT instability (after Lord Rayleigh and G. I. Taylor), is an instability of an interface between two fluids of different densities which occurs when the lighter fluid is pushing the heavier fluid. Examples include the behavior of water suspended above oil in the gravity of Earth, mushroom clouds like those from volcanic eruptions and atmospheric nuclear explosions, supernova explosions in which expanding core gas is accelerated into denser shell gas, instabilities in plasma fusion reactors and inertial confinement fusion.
Water suspended atop oil is an everyday example of Rayleigh–Taylor instability, and it may be modeled by two completely plane-parallel layers of immiscible fluid, the denser fluid on top of the less dense one and both subject to the Earth's gravity. The equilibrium here is unstable to any perturbations or disturbances of the interface: if a parcel of heavier fluid is displaced downward with an equal volume of lighter fluid displaced upwards, the potential energy of the configuration is lower than the initial state. Thus the disturbance will grow and lead to a further release of potential energy, as the denser material moves down under the (effective) gravitational field, and the less dense material is further displaced upwards. This was the set-up as studied by Lord Rayleigh. The important insight by G. I. Taylor was his realisation that this situation is equivalent to the situation when the fluids are accelerated, with
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https://en.wikipedia.org/wiki/Enterochromaffin-like%20cell
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Enterochromaffin-like cells or ECL cells are a type of neuroendocrine cell found in the gastric glands of the gastric mucosa beneath the epithelium, in particular in the vicinity of parietal cells, that aid in the production of gastric acid via the release of histamine. They are also considered a type of enteroendocrine cell.
Function
ECL cells synthesize and secrete histamine. These cells are stimulated by the hormones gastrin (not depicted in the adjacent diagram) and pituitary adenylyl cyclase-activating peptide. G cells are stimulated by vagal stimulation through the neurotransmitter gastrin-releasing peptide; this causes the G cells to secrete gastrin, which in turn stimulates ECL cells to release histamine. Note that this circuit is not activated by acetylcholine, which is of particular importance because the administration of atropine will not block the vagal stimulation of the G cells, as ACh is not the neurotransmitter for these cells.
However, ECL cells are activated directly by ACh on M1 receptors from direct vagal innervation leading to histamine release. This pathway will be inhibited by atropine.
Gastrin is transferred from a specific type of G cell in the gastric epithelium to the ECL cells by blood. Histamine and gastrin act synergistically as the most important stimulators of hydrochloric acid secretion from parietal cells and stimulators of secretion of pepsinogen from chief cells. The most important inhibitor of the ECL cell is somatostatin from oxy
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https://en.wikipedia.org/wiki/Silver%20staining
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In pathology, silver staining is the use of silver to selectively alter the appearance of a target in microscopy of histological sections; in temperature gradient gel electrophoresis; and in polyacrylamide gels.
In traditional stained glass, silver stain is a technique to produce yellow to orange or brown shades (or green on a blue glass base), by adding a mixture containing silver compounds (notably silver nitrate), and firing lightly. It was introduced soon after 1800, and is the "stain" in the term "stained glass". Silver compounds are mixed with binding substances, applied to the surface of glass, and then fired in a furnace or kiln.
History
Camillo Golgi perfected silver staining for the study of the nervous system. Although the exact chemical mechanism by which this occurs is unknown, Golgi's method stains a limited number of cells at random in their entirety.
Silver staining was introduced by Kerenyi and Gallyas as a sensitive procedure to detect trace amounts of proteins in gels. The technique has been extended to the study of other biological macromolecules that have been separated in a variety of supports.
Classical Coomassie brilliant blue staining can usually detect a 50 ng protein band; silver staining increases the sensitivity typically 50 times.
Many variables can influence the color intensity and every protein has its own staining characteristics; clean glassware, pure reagents, and water of highest purity are the key points to successful staining.
Chemi
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https://en.wikipedia.org/wiki/Trident%20Microsystems
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Trident Microsystems was a fabless semiconductor company that became in the 1990s a well-known supplier of integrated circuits (commonly called "chips") for video display controllers used in video cards and on motherboards for desktop PCs and laptops. In 2003, it transformed itself into being a supplier of display processors for digital televisions, and primarily LCD TVs starting from 2005, at a time when the global LCD TV market started showing strong growth.
It filed for bankruptcy protection in January 2012 and the delisting of its common stock from the NASDAQ stock market was announced shortly thereafter.
History
PC graphics
Established in 1987, Trident gained a reputation for selling inexpensive (for the time) but slow SVGA components. Many OEMs built add-in-boards using Trident VGA chipsets. As the PC graphics market shifted from simple framebuffer displays (basic VGA color monitor and later multi-resolution SVGA output) to more advanced 2D hardware acceleration such a BitBLT engine and color-space conversion (not to be confused with 3D hardware-acceleration), Trident continued its strategy of selling modestly performing chips at compelling price points. In the mid-1990s, the company (briefly) caught up with its main competition: the TGUI-9680's feature-set was comparable to the S3 Graphics Trio64V+, although the Trio64V+ outperformed the 9680 in true-color mode.
The rapid introduction of 3D graphics caught many graphics suppliers off guard, including Trident. It
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