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https://en.wikipedia.org/wiki/Thorite | Thorite, (Th,U)SiO4, is a rare nesosilicate of thorium that crystallizes in the tetragonal system and is isomorphous with zircon and hafnon. It is the most common mineral of thorium and is nearly always strongly radioactive. It was named in 1829 to reflect its thorium content. Thorite was discovered in 1828 on the island of Løvøya, Norway, by the vicar and mineralogist, Hans Morten Thrane Esmark, who sent the first specimens of this black mineral to his father, Jens Esmark, who was a professor of mineralogy and geology.
Occurrence
Specimens of thorite generally come from igneous pegmatites and volcanic extrusive rocks, hydrothermal veins and contact metamorphic rocks. It is also known to occur as small grains in detrital sands. Crystals are rare, but when found can produce nicely shaped short prismatic crystals with pyramidal terminations.
It is commonly associated with zircon, monazite, gadolinite, fergusonite, uraninite, yttrialite and pyrochlore.
Thorite is currently an important ore of uranium. A variety of thorite, often called "uranothorite", is particularly rich in uranium and has been a viable uranium ore at Bancroft in Ontario, Canada. Other varieties of thorite include "orangite", an orange variety, and "calciothorite", an impure variety with trace amounts of calcium.
Properties
Thorite is commonly metamict and hydrated, making it optically isotropic and amorphous. Owing to differences in composition, the specific gravity varies from 4.4 to 6.6 g/cm3. Hardness i |
https://en.wikipedia.org/wiki/Divide-and-conquer%20eigenvalue%20algorithm | Divide-and-conquer eigenvalue algorithms are a class of eigenvalue algorithms for Hermitian or real symmetric matrices that have recently (circa 1990s) become competitive in terms of stability and efficiency with more traditional algorithms such as the QR algorithm. The basic concept behind these algorithms is the divide-and-conquer approach from computer science. An eigenvalue problem is divided into two problems of roughly half the size, each of these are solved recursively, and the eigenvalues of the original problem are computed from the results of these smaller problems.
Here we present the simplest version of a divide-and-conquer algorithm, similar to the one originally proposed by Cuppen in 1981. Many details that lie outside the scope of this article will be omitted; however, without considering these details, the algorithm is not fully stable.
Background
As with most eigenvalue algorithms for Hermitian matrices, divide-and-conquer begins with a reduction to tridiagonal form. For an matrix, the standard method for this, via Householder reflections, takes floating point operations, or if eigenvectors are needed as well. There are other algorithms, such as the Arnoldi iteration, which may do better for certain classes of matrices; we will not consider this further here.
In certain cases, it is possible to deflate an eigenvalue problem into smaller problems. Consider a block diagonal matrix
The eigenvalues and eigenvectors of are simply those of and , and |
https://en.wikipedia.org/wiki/DAMA/NaI | The DAMA/NaI experiment investigated the presence of dark matter particles in the galactic halo by exploiting the model-independent annual modulation signature. Based on the Earth's orbit around the Sun and the solar system's speed with respect to the center of the galaxy (which on short time scales can be considered constant), the Earth should be exposed to a higher flux of dark matter particles around June 1, when its orbital speed is added to the one of the solar system with respect to the galaxy and to a smaller one around December 2, when the two velocities are subtracted. The annual modulation signature is distinctive since the effect induced by dark matter particles must simultaneously satisfy many requirements.
Description
The experimental set-up was located deep underground in the Laboratori Nazionali del Gran Sasso in Italy.
The experimental set-up was made by nine 9.70 kg low-radioactivity scintillating thallium-doped sodium iodide crystals [NaI(Tl)]. Each crystal was faced by two low-background photomultipliers through 10 cm light guides. The detectors were installed inside a sealed copper box flushed with highly pure nitrogen in order to insulate the detectors from air that contains trace amounts of radon, a radioactive gas. To reduce the natural environmental background the copper box is enclosed inside a multicomponent multi-ton passive shield made of copper, lead, polyethylene/paraffin, cadmium foil. A plexiglas box encloses the whole shield and is also kep |
https://en.wikipedia.org/wiki/Theophilus%20Presbyter | Theophilus Presbyter (fl. c. 1070–1125) is the pseudonymous author or compiler of a Latin text containing detailed descriptions of various medieval arts, a text commonly known as the Schedula diversarum artium ("List of various arts") or De diversis artibus ("On various arts"), probably first compiled between 1100 and 1120. The oldest manuscript copies of the work are found in Vienna (Austrian National Library, Codex 2527) and in Wolfenbüttel (Herzog-August-Bibliothek, Cod. Guelf. Gud. Lat. 69 2°). Gotthold Ephraim Lessing rediscovered the document when he worked as librarian in Wolfenbüttel, and published excerpts in 1774. These aroused great interest as they disproved Vasari's myth of Jan van Eyck developing the technique of oil painting in the early 15th century, about which antiquaries had already become suspicious.
Theophilus' Schedula allows detailed insights into the techniques used in the applied arts in the high Middle Ages. The work is divided into three books. The first covers the production and use of painting and drawing materials (painting techniques, paints, and ink), especially for illumination of texts and painting of walls. The second deals with the production of stained glass and techniques of glass painting, while the last deals with various techniques of goldsmithing and other metalwork. It also includes an introduction into the building of organs. Theophilus contains perhaps the earliest reference to oil paint. The work has been translated into English |
https://en.wikipedia.org/wiki/Nipple%20discharge | Nipple discharge is fluid from the nipple, with or without squeezing the breast. The discharge can be milky, clear, green, purulent, bloody, or faintly yellow. The consistency can be thick, thin, sticky, or watery.
Nipple discharge may be normal, such as milk in late pregnancy or after childbirth, and in newborns during the first weeks of life. It may also be normal following squeezing, in women during the reproductive years. It is likely abnormal if it occurs in men, contains blood, is from only one breast, or is associated with a breast lump, swelling, redness or overlying skin changes. Reasons for abnormal discharge include an intraductal papilloma, duct ectasia, blocked milk duct, infected breast (mastitis or breast abscess), breast cancer, certain medications, and conditions that raise prolactin.
Milky discharge in a non-pregnant, non-breast feeding women is evaluated differently to other abnormal nipple discharge. Often, the cause can be determined based on symptoms and examination. Blood tests may be done to rule out low thyroid or high prolactin. Other tests may include mammography, breast ultrasound, breast biopsy, or skin biopsy.
Treatment depends on the underlying cause. Duct ectasia may be treated with surgical removal of the ducts involved. Infectious causes may require antibiotics or incision and drainage. Nipple discharge is the third most common breast complaint by women, after breast pain and a breast lump. About 3% of breast cancer cases are associated w |
https://en.wikipedia.org/wiki/Francis%20Thomas%20Bacon | Francis Thomas Bacon OBE FREng FRS (21 December 1904 – 24 May 1992) was an English engineer who in 1932 developed the first practical hydrogen–oxygen fuel cell. It is used to generate power for space capsules and satellites.
Life and works
Francis Thomas Bacon was born in 1904 at Ramsden Hall, Billericay, Essex, England. An engineer at Trinity College, Cambridge, in 1932 he developed the fuel cell which was used as part of the Apollo moon project in the 1960s. Fuel cells were first demonstrated by Sir William Robert Grove in 1839, but his invention lay largely dormant for over 100 years until it was revived by Bacon. The alkaline fuel cell (AFC), also known as the Bacon fuel cell after its inventor, has been used in NASA space programs since the mid-1960s to generate power for satellites and space capsules. The U.S. President Richard Nixon welcomed Bacon to the White House, and told him; "Without you Tom, we wouldn't have gotten to the moon.” After the successful lunar landing of Apollo 11 in July 1969, Tom and his wife Barbara met astronauts Neil Armstrong, Buzz Aldrin and Michael Collins at a reception hosted by British Prime Minister Harold Wilson at 10 Downing Street.
Bacon was a descendant of the family of the philosopher Sir Francis Bacon (who had no children), and he was educated at Eton College and Trinity College, Cambridge. After Cambridge he became an apprentice with the Newcastle engineering firm owned by Sir Charles Parsons, and was strongly influenced by him. |
https://en.wikipedia.org/wiki/Organic%20semiconductor | Organic semiconductors are solids whose building blocks are pi-bonded molecules or polymers made up by carbon and hydrogen atoms and – at times – heteroatoms such as nitrogen, sulfur and oxygen. They exist in the form of molecular crystals or amorphous thin films. In general, they are electrical insulators, but become semiconducting when charges are either injected from appropriate electrodes, upon doping or by photoexcitation.
General properties
In molecular crystals the energetic separation between the top of the valence band and the bottom conduction band, i.e. the band gap, is typically 2.5–4 eV, while in inorganic semiconductors the band gaps are typically 1–2 eV. This implies that they are, in fact, insulators rather than semiconductors in the conventional sense. They become semiconducting only when charge carriers are either injected from the electrodes or generated by intentional or unintentional doping. Charge carriers can also be generated in the course of optical excitation. It is important to realize, however, that the primary optical excitations are neutral excitons with a Coulomb-binding energy of typically 0.5–1.0 eV. The reason is that in organic semiconductors their dielectric constants are as low as 3–4. This impedes efficient photogeneration of charge carriers in neat systems in the bulk. Efficient photogeneration can only occur in binary systems due to charge transfer between donor and acceptor moieties. Otherwise neutral excitons decay radiatively to the |
https://en.wikipedia.org/wiki/Columnar%20phase | The columnar phase is a class of mesophases in which molecules assemble into cylindrical structures to act as mesogens. Originally, these kinds of liquid crystals were called discotic liquid crystals or bowlic liquid crystals because the columnar structures are composed of flat-shaped discotic or bowl-shaped molecules stacked one-dimensionally. Since recent findings provide a number of columnar liquid crystals consisting of non-discoid mesogens, it is more common now to classify this state of matter and compounds with these properties as columnar liquid crystals.
Takuzo Aida and co-workers recently reported cyclic peptides that self-assemble into polar columnar organizations. These materials can be unidirectionally aligned over large areas by application of an external electric field.
Classes
Columnar liquid crystals are grouped by their structural order and the ways of packing of the columns. Nematic columnar liquid crystals have no long-range order and are less organized than other columnar liquid crystals. Other columnar phases with long-range order are classified by their two-dimensional lattices: hexagonal, tetragonal, rectangular, and oblique phases.
The discotic nematic phase includes nematic liquid crystals composed of flat-shaped discotic molecules without long-range order. In this phase, molecules do not form specific columnar assemblies but only float with their short axes in parallel to the director (a unit vector which defines the liquid-crystalline alignmen |
https://en.wikipedia.org/wiki/Classification%20of%20Clifford%20algebras | In abstract algebra, in particular in the theory of nondegenerate quadratic forms on vector spaces, the structures of finite-dimensional real and complex Clifford algebras for a nondegenerate quadratic form have been completely classified. In each case, the Clifford algebra is algebra isomorphic to a full matrix ring over R, C, or H (the quaternions), or to a direct sum of two copies of such an algebra, though not in a canonical way. Below it is shown that distinct Clifford algebras may be algebra-isomorphic, as is the case of Cl1,1(R) and Cl2,0(R), which are both isomorphic as rings to the ring of two-by-two matrices over the real numbers.
The significance of this result is that the additional structure on a Clifford algebra relative to the "underlying" associative algebra — namely, the structure given by the grade involution automorphism and reversal anti-automorphism (and their composition, the Clifford conjugation) — is in general an essential part of its definition, not a procedural artifact of its construction as the quotient of a tensor algebra by an ideal. The category of Clifford algebras is not just a selection from the category of matrix rings, picking out those in which the ring product can be constructed as the Clifford product for some vector space and quadratic form. With few exceptions, "forgetting" the additional structure (in the category theory sense of a forgetful functor) is not reversible.
Continuing the example above: Cl1,1(R) and Cl2,0(R) share the s |
https://en.wikipedia.org/wiki/Have%20Quick | [[File:Arc-164-rt.jpg|thumb|200px|UHF-Aircraft station AN/ARC-164 HAVE QUICK II]]
HAVE QUICK (also HAVEQUICK, short HQ) is an ECM-resistant frequency-hopping system used to protect military aeronautical mobile (OR) radio traffic.
Since the end of World War II, U.S. and Allied military aircraft have used AM radios in the NATO harmonised 225–400 MHz UHF band (part of NATO B band) for short range air-to-air and ground-to-air communications. During development and the procurement of UHF radios, military planners did not require features to secure communications for aircraft and helicopters from jamming until the post-Vietnam War era. Progress in electronics in the 1970s reached a point where anyone with an inexpensive radio frequency scanner or receiver set could intercept military communications. Once the target frequencies were identified, radio frequency jamming could easily be employed to degrade or completely disable communications.
The HAVE QUICK program was a response to this problem. Engineers recognized that newer aircraft radios already included all-channel frequency synthesizers along with keyboards and displays for data entry. The only other system requirements to achieve the desired anti-jam functionality were an accurate clock (for timed synchronization) and a microprocessor to add frequency hopping to existing radios.
Aircraft and ground radios that employ HAVE QUICK must be initialized with accurate time of day (TOD; usually from a GPS receiver), a word of th |
https://en.wikipedia.org/wiki/Selection%20%28genetic%20algorithm%29 | Selection is the stage of a genetic algorithm or more general evolutionary algorithm in which individual genomes are chosen from a population for later breeding (e.g., using the crossover operator). Selection mechanisms are also used to choose candidate solutions (individuals) for the next generation. Retaining the best individuals in a generation unchanged in the next generation, is called elitism or elitist selection. It is a successful (slight) variant of the general process of constructing a new population.
A selection procedure for breeding used early on may be implemented as follows:
The fitness values that have been computed (fitness function) are normalized, such that the sum of all resulting fitness values equals 1.
Accumulated normalized fitness values are computed: the accumulated fitness value of an individual is the sum of its own fitness value plus the fitness values of all the previous individuals; the accumulated fitness of the last individual should be 1, otherwise something went wrong in the normalization step.
A random number R between 0 and 1 is chosen.
The selected individual is the first one whose accumulated normalized value is greater than or equal to R.
For many problems the above algorithm might be computationally demanding. A simpler and faster alternative uses the so-called stochastic acceptance.
If this procedure is repeated until there are enough selected individuals, this selection method is called fitness proportionate selection or roulette |
https://en.wikipedia.org/wiki/Laplace%20distribution | In probability theory and statistics, the Laplace distribution is a continuous probability distribution named after Pierre-Simon Laplace. It is also sometimes called the double exponential distribution, because it can be thought of as two exponential distributions (with an additional location parameter) spliced together along the abscissa, although the term is also sometimes used to refer to the Gumbel distribution. The difference between two independent identically distributed exponential random variables is governed by a Laplace distribution, as is a Brownian motion evaluated at an exponentially distributed random time. Increments of Laplace motion or a variance gamma process evaluated over the time scale also have a Laplace distribution.
Definitions
Probability density function
A random variable has a distribution if its probability density function is
Here, is a location parameter and , which is sometimes referred to as the "diversity", is a scale parameter. If and , the positive half-line is exactly an exponential distribution scaled by 1/2.
The probability density function of the Laplace distribution is also reminiscent of the normal distribution; however, whereas the normal distribution is expressed in terms of the squared difference from the mean , the Laplace density is expressed in terms of the absolute difference from the mean. Consequently, the Laplace distribution has fatter tails than the normal distribution.
Cumulative distribution function
The Lap |
https://en.wikipedia.org/wiki/Tom%20Clancy%27s%20Splinter%20Cell%3A%20Pandora%20Tomorrow | Tom Clancy's Splinter Cell: Pandora Tomorrow is a 2004 stealth game developed and published by Ubisoft Shanghai and Ubisoft Milan. The game is the sequel to Splinter Cell and the second game in the Splinter Cell series endorsed by writer Tom Clancy. It follows the covert activities of Sam Fisher, an agent working for a black-ops branch of the National Security Agency (NSA) called "Third Echelon". Michael Ironside returns to voice Sam Fisher, while Dennis Haysbert voices the character Irving Lambert, Fisher's boss, making this the only time he is not voiced by Don Jordan. Lalo Schifrin provides the theme music for the game.
Splinter Cell: Pandora Tomorrow received mostly positive reviews on release, with critics calling it a strong follow-up and praising its multiplayer component, which would become a staple of the series. A side-scrolling adaptation for Game Boy Advance and mobile phones was released to mixed reception. A remastered high definition version was released on PlayStation 3 in September 2011. A sequel, titled Chaos Theory, released in 2005.
Gameplay
The gameplay of Pandora Tomorrow is largely unchanged from the original Splinter Cell. The game features some moderate graphical improvements, as well as minor gameplay changes such as the fact that health kits are no longer an inventory item, and the addition of a laser sight to Sam's pistol that allows the player to know exactly where the rounds will strike, even when moving around. Also, Sam can now whistle to at |
https://en.wikipedia.org/wiki/Class%20B | Class B may refer to:
Class B (baseball), a defunct class in minor league baseball in North America
Class B (classification), a Paralympic wheelchair fencing classification
Class B drug, in British law
Class B share, a “class” of common or preferred stock
Class B star
Barry Railway Class B, a British steam locomotive
LNWR Class B, a British steam locomotive
Class B office space, a step below Class A office space
An Army Service Uniform
An airspace class defined by the ICAO
A power amplifier class
A class of broadcast station in North America
An electronic device conforming to FCC rule Title 47 CFR Part 15, Subpart B, Class B
An explosives category for professional fireworks; see Fireworks policy in the United States
A network in the Internet classful network system
A pathogen treatment and pollutant criterion, an EPA reuse category in biosolids
A recreational vehicle, or campervan
A class of boat in the European Union
See also
B-class (disambiguation)
Type B (disambiguation) |
https://en.wikipedia.org/wiki/Ampelography | Ampelography (ἄμπελος, "vine" + γράφος, "writing") is the field of botany concerned with the identification and classification of grapevines, Vitis spp. Traditionally this has been done by comparing the shape and colour of the vine leaves and grape berries; more recently the study of vines has been revolutionised by DNA fingerprinting.
Early history
The grape vine is an extremely variable species and some varieties, such as Pinot, mutate particularly frequently. At the same time, the wine and table grape industries have been important since ancient times, so large sums of money can depend on the correct identification of different varieties and clones of grapevines.
The science of ampelography began seriously in the 19th century, when it became important to understand more about the different species of vine, as they had very different resistance to disease and pests such as phylloxera.
Many vine identification books were published at this time, one of which is Victor Rendu's Ampélographie française of 1857, featuring hand-colored lithographs by Eugene Grobon.
Pierre Galet
Until the Second World War, ampelography had been an art. Then Pierre Galet of the École nationale supérieure agronomique de Montpellier made a systematic assembly of criteria for the identification of vines. The Galet system was based on the shape and contours of the leaves, the characteristics of growing shoots, shoot tips, petioles, the sex of the flowers, the shape of the grape clusters and the colo |
https://en.wikipedia.org/wiki/AWStats | AWStats (Advanced Web Statistics) is an open source Web analytics reporting tool, suitable for analyzing data from Internet services such as web, streaming media, mail, and FTP servers. AWStats parses and analyzes server log files, producing HTML reports. Data is visually presented within reports by tables and bar graphs. Static reports can be created through a command line interface, and on-demand reporting is supported through a Web browser CGI program.
AWStats supports most major web server log file formats including Apache (NCSA combined/XLF/ELF log format or Common Log Format (CLF)), WebStar, IIS (W3C log format), and many other common web server log formats.
Development was moved from SourceForge to GitHub in 2014.
Cross-platform availability
Written in Perl, AWStats can be deployed on almost any operating system. It is a server-based website log analysis tool, with packages available for most Linux distributions. AWStats can be installed on a workstation, such as Microsoft Windows, for local use in situations where log files can be downloaded from a remote server.
Licensing
AWStats is licensed under the GNU General Public License (GPL).
Support
Proper web log analysis tool configuration and report interpretation requires a bit of technical and business knowledge. AWStats support resources include documentation and user community forums
Security considerations
The on-demand CGI program has been the object of security exploits, as is the case of many CGI programs. |
https://en.wikipedia.org/wiki/Class%20C | Class C may refer to:
Class C amplifier, a category of electronic amplifier
Class C (baseball), a defunct class in minor league baseball in North America
Class C stellar classification for a carbon star
Class C drugs, under the Misuse of Drugs Act (disambiguation) of multiple Commonwealth Nations
Class C drug, as defined by the UK's Misuse of Drugs Act 1971
Class C network, a type of IP address on a Classful network
Class C, an airspace class as defined by the ICAO
Class C, a type of driver's license in the United States
Class C, a large goods vehicle driving licence in the United Kingdom
Class C, from the List of North American broadcast station classes
Class C, a type of smooth function in mathematics
Class C motorhome, a type of recreational vehicle which has a bed over the driver's cab
See also
C class (disambiguation)
C (disambiguation)
Class (disambiguation)
C series (disambiguation) |
https://en.wikipedia.org/wiki/Intrusive%20rock | Intrusive rock is formed when magma penetrates existing rock, crystallizes, and solidifies underground to form intrusions, such as batholiths, dikes, sills, laccoliths, and volcanic necks.
Intrusion is one of the two ways igneous rock can form. The other is extrusion, such as a volcanic eruption or similar event. An intrusion is any body of intrusive igneous rock, formed from magma that cools and solidifies within the crust of the planet. In contrast, an extrusion consists of extrusive rock, formed above the surface of the crust.
Some geologists use the term plutonic rock synonymously with intrusive rock, but other geologists subdivide intrusive rock, by crystal size, into coarse-grained plutonic rock (typically formed deeper in the Earth's crust in batholiths or stocks) and medium-grained subvolcanic or hypabyssal rock (typically formed higher in the crust in dikes and sills).
Classification
Because the solid country rock into which magma intrudes is an excellent insulator, cooling of the magma is extremely slow, and intrusive igneous rock is coarse-grained (phaneritic). However, the rate of cooling is greatest for intrusions at relatively shallow depth, and the rock in such intrusions is often much less coarse-grained than intrusive rock formed at greater depth. Coarse-grained intrusive igneous rocks that form at depth within the Earth are called abyssal or plutonic while those that form near the surface are called subvolcanic or hypabyssal.
Plutonic rocks are classifie |
https://en.wikipedia.org/wiki/Cell%20culture | Cell culture or tissue culture is the process by which cells are grown under controlled conditions, generally outside of their natural environment. The term "tissue culture" was coined by American pathologist Montrose Thomas Burrows. This technique is also called micropropagation. After the cells of interest have been isolated from living tissue, they can subsequently be maintained under carefully controlled conditions. They need to be kept at body temperature (37 °C) in an incubator. These conditions vary for each cell type, but generally consist of a suitable vessel with a substrate or rich medium that supplies the essential nutrients (amino acids, carbohydrates, vitamins, minerals), growth factors, hormones, and gases (CO2, O2), and regulates the physio-chemical environment (pH buffer, osmotic pressure, temperature). Most cells require a surface or an artificial substrate to form an adherent culture as a monolayer (one single-cell thick), whereas others can be grown free floating in a medium as a suspension culture. This is typically facilitated via use of a liquid, semi-solid, or solid growth medium, such as broth or agar. Tissue culture commonly refers to the culture of animal cells and tissues, with the more specific term plant tissue culture being used for plants. The lifespan of most cells is genetically determined, but some cell-culturing cells have been “transformed” into immortal cells which will reproduce indefinitely if the optimal conditions are provided.
In pr |
https://en.wikipedia.org/wiki/Token%20bucket | The token bucket is an algorithm used in packet-switched and telecommunications networks. It can be used to check that data transmissions, in the form of packets, conform to defined limits on bandwidth and burstiness (a measure of the unevenness or variations in the traffic flow). It can also be used as a scheduling algorithm to determine the timing of transmissions that will comply with the limits set for the bandwidth and burstiness: see network scheduler.
Overview
The token bucket algorithm is based on an analogy of a fixed capacity bucket into which tokens, normally representing a unit of bytes or a single packet of predetermined size, are added at a fixed rate. When a packet is to be checked for conformance to the defined limits, the bucket is inspected to see if it contains sufficient tokens at that time. If so, the appropriate number of tokens, e.g. equivalent to the length of the packet in bytes, are removed ("cashed in"), and the packet is passed, e.g., for transmission. The packet does not conform if there are insufficient tokens in the bucket, and the contents of the bucket are not changed. Non-conformant packets can be treated in various ways:
They may be dropped.
They may be enqueued for subsequent transmission when sufficient tokens have accumulated in the bucket.
They may be transmitted, but marked as being non-conformant, possibly to be dropped subsequently if the network is overloaded.
A conforming flow can thus contain traffic with an average rate up |
https://en.wikipedia.org/wiki/Notch%20signaling%20pathway | The Notch signaling pathway is a highly conserved cell signaling system present in most animals. Mammals possess four different notch receptors, referred to as NOTCH1, NOTCH2, NOTCH3, and NOTCH4. The notch receptor is a single-pass transmembrane receptor protein. It is a hetero-oligomer composed of a large extracellular portion, which associates in a calcium-dependent, non-covalent interaction with a smaller piece of the notch protein composed of a short extracellular region, a single transmembrane-pass, and a small intracellular region.
Notch signaling promotes proliferative signaling during neurogenesis, and its activity is inhibited by Numb to promote neural differentiation. It plays a major role in the regulation of embryonic development.
Notch signaling is dysregulated in many cancers, and faulty notch signaling is implicated in many diseases, including T-cell acute lymphoblastic leukemia (T-ALL), cerebral autosomal-dominant arteriopathy with sub-cortical infarcts and leukoencephalopathy (CADASIL), multiple sclerosis, Tetralogy of Fallot, and Alagille syndrome. Inhibition of notch signaling inhibits the proliferation of T-cell acute lymphoblastic leukemia in both cultured cells and a mouse model.
Discovery
In 1914, John S. Dexter noticed the appearance of a notch in the wings of the fruit fly Drosophila melanogaster. The alleles of the gene were identified in 1917 by American evolutionary biologist Thomas Hunt Morgan. Its molecular analysis and sequencing was indep |
https://en.wikipedia.org/wiki/Thermal%20cycler | The thermal cycler (also known as a thermocycler, PCR machine or DNA amplifier) is a laboratory apparatus most commonly used to amplify segments of DNA via the polymerase chain reaction (PCR). Thermal cyclers may also be used in laboratories to facilitate other temperature-sensitive reactions, including restriction enzyme digestion or rapid diagnostics. The device has a thermal block with holes where tubes holding the reaction mixtures can be inserted. The cycler then raises and lowers the temperature of the block in discrete, pre-programmed steps.
History
The earliest thermal cyclers were designed for use with the Klenow fragment of DNA polymerase I. Since this enzyme is destroyed during each heating step of the amplification process, new enzyme had to be added every cycle. This led to a cumbersome machine based on an automated pipettor, with open reaction tubes. Later, the PCR process was adapted to the use of thermostable DNA polymerase from Thermus aquaticus, which greatly simplified the design of the thermal cycler. While in some old machines the block is submerged in an oil bath to control temperature, in modern PCR machines a Peltier element is commonly used. Quality thermal cyclers often contain silver blocks to achieve fast temperature changes and uniform temperature throughout the block. Other cyclers have multiple blocks with high heat capacity, each of which is kept at a constant temperature, and the reaction tubes are moved between them by means of an auto |
https://en.wikipedia.org/wiki/Invasive%20species%20in%20Australia | Invasive species in Australia are a serious threat to the native biodiversity, and an ongoing cost to Australian agriculture. Numerous species arrived with European maritime exploration and colonisation of Australia and steadily since then.
Management and the prevention of the introduction of new invasive species are key environmental and agricultural policy issues for the Australian federal and state governments. The management of weeds costs A$1.5 billion on weed control and a further $2.5 billion yearly in lost agricultural production.
Causes
Both geologic and climatic events helped to make Australia's fauna unique. Australia was once part of the southern supercontinent Gondwana, which also included South America, Africa, India and Antarctica. Gondwana began to break up 140 million years ago (MYA); 50 MYA Australia separated from Antarctica and was relatively isolated until the collision of the Indo-Australian Plate with Asia in the Miocene era 5.3 MYA. As Australia drifted, it was isolated from evolutionary pressures in the rest of the world. Other examples of island isolation include Madagascar, New Zealand, Socotra, the Galapagos and Mauritius. The geographic isolation of Australia created a sharp division between Australian fauna and Asian fauna at the Wallace line.
Humans arrived in Australia between 65,000 and 80,000 years ago, living alongside megafauna for 20,000-25,000 years before the megafaunal extinctions that were likely caused by, or partly contributed to |
https://en.wikipedia.org/wiki/Birch%E2%80%93Murnaghan%20equation%20of%20state | The Birch–Murnaghan isothermal equation of state, published in 1947 by Albert Francis Birch of Harvard, is a relationship between the volume of a body and the pressure to which it is subjected. Birch proposed this equation based on the work of Francis Dominic Murnaghan of Johns Hopkins University published in 1944, so that the equation is named in honor of both scientists.
Expressions for the equation of state
The third-order Birch–Murnaghan isothermal equation of state is given by
where P is the pressure, V0 is the reference volume, V is the deformed volume, B0 is the bulk modulus, and B0' is the derivative of the bulk modulus with respect to pressure. The bulk modulus and its derivative are usually obtained from fits to experimental data and are defined as
and
The expression for the equation of state is obtained by expanding the free energy f in the form of a series:
The internal energy, , is found by integration of the pressure:
See also
Albert Francis Birch
Francis Dominic Murnaghan
Murnaghan equation of state
References
Continuum mechanics
Eponymous equations of physics
Equations of state |
https://en.wikipedia.org/wiki/Eagle%27s%20minimal%20essential%20medium | Minimal Essential Medium (MEM) is a synthetic cell culture medium developed by Harry Eagle first published in 1959 in Science that can be used to maintain cells in tissue culture. It is based on 6 salts and glucose described in Earle's salts in 1934: (calcium chloride, potassium chloride, magnesium sulfate, sodium chloride, sodium phosphate and sodium bicarbonate), supplemented with 13 essential amino acids, and 8 vitamins: thiamine (vitamin B1), riboflavin (vitamin B2), nicotinamide (vitamin B3), pantothenic acid (vitamin B5), pyrodoxine (vitamin B6), folic acid (vitamin B9), choline, and myo-inositol (originally known as vitamin B8).
Many variations of this medium have been developed, mostly adding additional vitamins, amino acids, and/or other nutrients.
Eagle developed his earlier "Basal Medium Eagle" (BME) in 1955–1957 on mouse L cells and human HeLa cells, with 13 essential amino acids and 9 vitamins added. BME contains biotin (vitamin B7), which Eagle later found to be superfluous. His 1959 "Minimal Essential Medium" doubles the amount of many amino acids to "conform more closely to the protein composition of cultured human cells. This permits the cultures to be kept for somewhat longer periods without refeeding".
DMEM (Dulbecco's Modified Eagle's Medium) was originally suggested as Eagle's medium with a 'Fourfold concentration of amino acids and vitamins' by Renato Dulbecco and G. Freeman published in 1959. The commercial versions of this medium have additional m |
https://en.wikipedia.org/wiki/Lzop | lzop is a free software file compression tool which implements the LZO algorithm and is licensed under the GPL.
Aimed at being very fast, lzop produces files slightly larger than gzip while only requiring a tenth of the CPU use and only slightly higher memory utilization. lzop is one of the fastest compressors available, a close second to lz4.
See also
List of archive formats
List of file archivers
Comparison of file archivers
References
External links
Free data compression software |
https://en.wikipedia.org/wiki/Sandhill | A sandhill is a type of ecological community or xeric wildfire-maintained ecosystem. It is not the same as a sand dune. It features very short fire return intervals, one to five years. Without fire, sandhills undergo ecological succession and become more oak dominated.
Entisols are the typical sandhill soil, deep well-drained and nutrient poor. In Florida, sandhills receive cm of rainfall per year, just like the more hydric ecosystems surrounding them. Sandhills are xeric because they have poor water holding capacity.
Dominant vegetation includes longleaf pine (Pinus palustris), American turkey oak (Quercus laevis), and wiregrass (Aristida stricta). A number of rare animals are typical of this habitat including the gopher tortoise (Gopherus polyphemus), red-cockaded woodpecker (Picoides borealis), Sherman's fox squirrel (Sciurus niger shermani), and striped newt (Notophthalmus perstriatus). Invasive species that are a problem on sandhills include Cogongrass (Imperata cylindrica), camphor laurels (Cinnamomum camphora), and Natal grass (Melinis repens).
See also
, another ecological community in the coastal plain of North America
References
External links
Fnai.org: Natural Communities Definitions for Florida
Wildfire ecology
Dunes of the United States
Plant communities of the Eastern United States
Plant communities of Florida
Natural history of Texas |
https://en.wikipedia.org/wiki/Hasse%27s%20theorem%20on%20elliptic%20curves | Hasse's theorem on elliptic curves, also referred to as the Hasse bound, provides an estimate of the number of points on an elliptic curve over a finite field, bounding the value both above and below.
If N is the number of points on the elliptic curve E over a finite field with q elements, then Hasse's result states that
The reason is that N differs from q + 1, the number of points of the projective line over the same field, by an 'error term' that is the sum of two complex numbers, each of absolute value
This result had originally been conjectured by Emil Artin in his thesis. It was proven by Hasse in 1933, with the proof published in a series of papers in 1936.
Hasse's theorem is equivalent to the determination of the absolute value of the roots of the local zeta-function of E. In this form it can be seen to be the analogue of the Riemann hypothesis for the function field associated with the elliptic curve.
Hasse-Weil Bound
A generalization of the Hasse bound to higher genus algebraic curves is the Hasse–Weil bound. This provides a bound on the number of points on a curve over a finite field. If the number of points on the curve C of genus g over the finite field of order q is , then
This result is again equivalent to the determination of the absolute value of the roots of the local zeta-function of C, and is the analogue of the Riemann hypothesis for the function field associated with the curve.
The Hasse–Weil bound reduces to the usual Hasse bound when app |
https://en.wikipedia.org/wiki/Hasse%20norm%20theorem | In number theory, the Hasse norm theorem states that if L/K is a cyclic extension of number fields, then if a nonzero element of K is a local norm everywhere, then it is a global norm.
Here to be a global norm means to be an element k of K such that there is an element l of L with ; in other words k is a relative norm of some element of the extension field L. To be a local norm means that for some prime p of K and some prime P of L lying over K, then k is a norm from LP; here the "prime" p can be an archimedean valuation, and the theorem is a statement about completions in all valuations, archimedean and non-archimedean.
The theorem is no longer true in general if the extension is abelian but not cyclic. Hasse gave the counterexample that 3 is a local norm everywhere for the extension but is not a global norm. Serre and Tate showed that another counterexample is given by the field where every rational square is a local norm everywhere but is not a global norm.
This is an example of a theorem stating a local-global principle.
The full theorem is due to . The special case when the degree n of the extension is 2 was proved by , and the special case when n is prime was proved by Furtwangler in 1902.
The Hasse norm theorem can be deduced from the theorem that an element of the Galois cohomology group H2(L/K) is trivial if it is trivial locally everywhere, which is in turn equivalent to the deep theorem that the first cohomology of the idele class group vanishes. This is t |
https://en.wikipedia.org/wiki/Lempel%E2%80%93Ziv%E2%80%93Oberhumer | Lempel–Ziv–Oberhumer (LZO) is a lossless data compression algorithm that is focused on decompression speed.
Design
The original "lzop" implementation, released in 1996, was developed by Markus Franz Xaver Johannes Oberhumer, based on earlier algorithms by Abraham Lempel and Jacob Ziv. The LZO library implements a number of algorithms with the following characteristics:
Higher compression speed compared to DEFLATE compression
Very fast decompression
Requires an additional buffer during compression (of size 8 kB or 64 kB, depending on compression level)
Requires no additional memory for decompression other than the source and destination buffers
Allows the user to adjust the balance between compression ratio and compression speed, without affecting the speed of decompression
LZO supports overlapping compression and in-place decompression. As a block compression algorithm, it compresses and decompresses blocks of data. Block size must be the same for compression and decompression. LZO compresses a block of data into matches (a sliding dictionary) and runs of non-matching literals to produce good results on highly redundant data and deals acceptably with non-compressible data, only expanding incompressible data by a maximum of 1/64 of the original size when measured over a block size of at least 1 kB.
Implementations
The reference implementation is written in ANSI C, and it has been made available as free software under the GNU General Public License. The copyright for |
https://en.wikipedia.org/wiki/Tollerton%2C%20Nottinghamshire | Tollerton is an English village and civil parish in the Rushcliffe district of Nottinghamshire, just south-east of Nottingham. Statistics from the 2021 census show the population of the village has increased to 2,486.
Governance
Tollerton has a parish council and is represented on Rushcliffe Borough Council. The Member of Parliament (MP) for Rushcliffe since December 2019 is the Conservative Ruth Edwards.
Tollerton Hall
St Hugh's College was founded in 1948 at Tollerton Hall by the Roman Catholic Diocese of Nottingham as its junior seminary, accepting boys from aged 11 upwards, but by 1969 it had opened its doors to secular students. It closed in 1986, leaving the hall as a corporate HQ until June 2017, when it was bought by a businessman, Ian Kershaw, for use as a private home again.
Event and amenities
There is an annual village fayre held in June. This gathers residents around craft stalls, entertainments, refreshments and small exhibitions. The money generated helps local charities.
The pub named the Air Hostess recalls Nottingham Airport at Tollerton. It is unusual in having a piste for playing pétanque. It used to have a large carved sign depicting an air hostess. However, in 2011, the then owners of the premises, Everards Brewery, decided to refurbish them and in doing so replaced the original sign with a conventional hanging sign depicting an air hostess. This changed to a hanging sign depicting Tollerton Hall, an aircraft and fields. A scheme was put in operation |
https://en.wikipedia.org/wiki/Aristida%20stricta | Aristida stricta is a warm-season grass, native to North America, that dominates understory vegetation in sandhills and flatwoods coastal plain ecosystems of the Carolinas in the Southeastern United States. It is known as wiregrass (due to its texture) and pineland three-awn grass.
Its common name, wiregrass, gave rise to the naming of the Wiregrass Region in which it is located.
This is a fast-growing species that regenerates quickly after fires. The plant depends on regular summer burning in order to stimulate flowering and seed production.
References
Further reading
stricta
Flora of North Carolina
Flora of South Carolina
Flora of Florida
Flora of Georgia (U.S. state) |
https://en.wikipedia.org/wiki/Flatwoods | Flatwoods, pineywoods, pine savannas and longleaf pine-wiregrass ecosystem are terms that refer to an ecological community in the southeastern coastal plain of North America. Flatwoods are an ecosystem maintained by wildfire or prescribed fire and are dominated by longleaf pine (Pinus palustris), and slash pine (Pinus elliotii) in the tree canopy and saw palmetto (Serenoa repens), gallberry (Ilex glabra) and other flammable evergreen shrubs in the understory, along with a high diversity of herb species. It was once one of the dominant ecosystem types of southeastern North America. Although grasses and pines are characteristic of this system, the precise composition changes from west to east, that is, from Texas to Florida. In Louisiana, savannas even differ between the east and west side of the Mississippi River. The key factor maintaining this habitat type is recurring fire. Without fire, the habitat is eventually invaded by other species of woody plants.
A number of rare and endangered animals are typical of this habitat including red-cockaded woodpeckers (Picoides borealis), gopher tortoises (Gopherus polyphemus), frosted flatwoods salamanders (Ambystoma cingulatum), and striped newts (Notophthalmus perstriatus). Many rare and usual herbaceous plants are found here, particularly orchids (e.g. Calopogon species, Pogonia ophioglossoides), sedges (e.g. Rhynchospora species) and carnivorous plants (e.g. Sarracenia species).
A second key factor is moisture. Overall, wet pine |
https://en.wikipedia.org/wiki/Hasse%E2%80%93Minkowski%20theorem | The Hasse–Minkowski theorem is a fundamental result in number theory which states that two quadratic forms over a number field are equivalent if and only if they are equivalent locally at all places, i.e. equivalent over every completion of the field (which may be real, complex, or p-adic). A related result is that a quadratic space over a number field is isotropic if and only if it is isotropic locally everywhere, or equivalently, that a quadratic form over a number field nontrivially represents zero if and only if this holds for all completions of the field. The theorem was proved in the case of the field of rational numbers by Hermann Minkowski and generalized to number fields by Helmut Hasse. The same statement holds even more generally for all global fields.
Importance
The importance of the Hasse–Minkowski theorem lies in the novel paradigm it presented for answering arithmetical questions: in order to determine whether an equation of a certain type has a solution in rational numbers, it is sufficient to test whether it has solutions over complete fields of real and p-adic numbers, where analytic considerations, such as Newton's method and its p-adic analogue, Hensel's lemma, apply. This is encapsulated in the idea of a local-global principle, which is one of the most fundamental techniques in arithmetic geometry.
Application to the classification of quadratic forms
The Hasse–Minkowski theorem reduces the problem of classifying quadratic forms over a number field K |
https://en.wikipedia.org/wiki/Hasse%27s%20theorem | In mathematics, there are several theorems of Helmut Hasse that are sometimes called Hasse's theorem:
Hasse norm theorem
Hasse's theorem on elliptic curves
Hasse–Arf theorem
Hasse–Minkowski theorem
See also
Hasse principle, the principle that an integer equation can be solved by piecing together modular solutions |
https://en.wikipedia.org/wiki/Purcell%20Society | The Purcell Society, founded in 1876 (principally by William Hayman Cummings) is an organization dedicated to making the complete musical works of Henry Purcell available. Between 1876 and 1965, scores of all the known works of Purcell were published, in 32 volumes. Advances in musical scholarship and editorial techniques in the decades after the first volumes were issued meant that by the second half of the 20th century they were no longer meeting the needs of users. Beginning in the 1960s, the Purcell Society began to issue revised versions of the scores. The website gives details of the scores in the revised series that are currently available.
Holding libraries
All volumes of the complete work of Henry Purcell published by the Purcell Society are available in the Zentral- und Landesbibliothek Berlin and the British Library in London.
The FAL library at the University of New Mexico has in its possession most of the volumes, with some added revised editions. The FAL is missing vols. 1, 6, 8, 10, 16, 18, 21, 23.
See also
List of compositions by Henry Purcell
Godfrey Edward Pellew Arkwright
External links
Official site of the Purcell Society
International music organizations
Organizations established in 1876
Music publishing companies of the United Kingdom
Music organisations based in the United Kingdom
Arts organizations established in the 1870s
1876 establishments in the United Kingdom |
https://en.wikipedia.org/wiki/Posta%2C%20Pirna | Posta is a village in the municipality of Pirna, in Saxony, Germany. It was incorporated into Pirna in 1922. It consists of Niederposta (Lower Posta) and Oberposta (Upper Posta). The place was mentioned for the first time in 1417. It is situated on the right bank of the river Elbe, northeast of Pirna town centre.
References
Pirna
Populated places in Saxon Switzerland |
https://en.wikipedia.org/wiki/U-87%20MG | In cell biology, U-87 MG is a human glioblastoma cell line that is commonly used in brain cancer research.
History and Characteristics
Formally known as U-87 MG (abbreviation for Uppsala 87 Malignant Glioma), the U87 cell line has an epithelial morphology and was obtained from a 44-year-old female patient in 1966 at Uppsala University. The cell line was thought to be deposited at the Memorial Sloan Kettering Cancer Center in 1973, after which the ATCC obtained it in 1982. However, in 2016 the commonly used version of U87MG (from the ATCC) was found to be non-identical to its patient of origin. Analysis of DNA profile and mtDNA position suggest that the Uppsala U-87 MG line is authentic to the original tumor tissue while the ATCC U-87 MG line is not; The ATCC line is likely a bona fide human glioblastoma cell line of unknown origin. The entire sequence of the genome of U-87 MG has been published in PLoS Genetics.
U-87 MG can be obtained from the American Type Culture Collection (ATCC) where it is known by the accession number HTB-14 and it is reported that the cell line comes from a male patient of unknown age.
Growth conditions
U87 growth media is generally made with Eagle's minimum essential medium + 10% FBS + 100 U/mL penicillin + 100 µg/mL streptomycin. It is propagated at 37 °C in a 5% carbon dioxide atmosphere.
References
External links
ATCC record for HTB-14
Cellosaurus entry for U87
Human cell lines |
https://en.wikipedia.org/wiki/N-Acetylmuramic%20acid | N-Acetylmuramic acid (NAM or MurNAc) is an organic compound with the chemical formula . It is a monomer of peptidoglycan in most bacterial cell walls, which is built from alternating units of N-acetylglucosamine (GlcNAc) and N-acetylmuramic acid, cross-linked by oligopeptides at the lactic acid residue of MurNAc.
Formation of NAM
NAM is an addition product of phosphoenolpyruvate and N-acetylglucosamine. This addition happens exclusively in the cell cytoplasm.
Clinical significance
N-Acetylmuramic acid (MurNAc) is part of the peptidoglycan polymer of bacterial cell walls. MurNAc is covalently linked to N-acetylglucosamine and may also be linked through the hydroxyl on carbon number 4 to the carbon of L-alanine. A pentapeptide composed of L-alanyl-D-isoglutaminyl-L-lysyl-D-alanyl-D-alanine is added to the MurNAc in the process of making the peptidoglycan strands of the cell wall.
Synthesis of NAM is inhibited by fosfomycin.
NAG and NAM cross-linking can be inhibited by antibiotics to inhibit pathogens from growing within the body. Therefore, both NAG and NAM are valuable polymers in medicinal research.
References
See also
Amino sugar
Glucosamine
Amino sugars
Monosaccharide derivatives
Monosaccharides
Membrane biology |
https://en.wikipedia.org/wiki/Oxaloacetic%20acid | Oxaloacetic acid (also known as oxalacetic acid or OAA) is a crystalline organic compound with the chemical formula HO2CC(O)CH2CO2H. Oxaloacetic acid, in the form of its conjugate base oxaloacetate, is a metabolic intermediate in many processes that occur in animals. It takes part in gluconeogenesis, the urea cycle, the glyoxylate cycle, amino acid synthesis, fatty acid synthesis and the citric acid cycle.
Properties
Oxaloacetic acid undergoes successive deprotonations to give the dianion:
HO2CC(O)CH2CO2H −O2CC(O)CH2CO2H + H+, pKa = 2.22
−O2CC(O)CH2CO2H −O2CC(O)CH2CO2− + H+, pKa = 3.89
At high pH, the enolizable proton is ionized:
−O2CC(O)CH2CO2− −O2CC(O−)CHCO2− + H+, pKa = 13.03
The enol forms of oxaloacetic acid are particularly stable. Keto-enol tautomerization is catalyzed by the enzyme oxaloacetate tautomerase. trans-Enol-oxaloacetate also appears when tartrate is the substrate for fumarase.
Biosynthesis
Oxaloacetate forms in several ways in nature. A principal route is upon oxidation of L-malate, catalyzed by malate dehydrogenase, in the citric acid cycle. Malate is also oxidized by succinate dehydrogenase in a slow reaction with the initial product being enol-oxaloacetate.
It also arises from the condensation of pyruvate with carbonic acid, driven by the hydrolysis of ATP:
CH3C(O)CO2− + HCO3− + ATP → −O2CCH2C(O)CO2− + ADP + Pi
Occurring in the mesophyll of plants, this process proceeds via phosphoenolpyruvate, catalysed by phospho |
https://en.wikipedia.org/wiki/Trypsinogen | Trypsinogen () is the precursor form (or zymogen) of trypsin, a digestive enzyme. It is produced by the pancreas and found in pancreatic juice, along with amylase, lipase, and chymotrypsinogen. It is cleaved to its active form, trypsin, by enteropeptidase, which is found in the intestinal mucosa. Once activated, the trypsin can cleave more trypsinogen into trypsin, a process called autoactivation. Trypsin cleaves the peptide bond on the carboxyl side of basic amino acids such as arginine and lysine.
Function
Trypsinogen is the proenzyme precursor of trypsin. Trypsinogen (the inactive form) is stored in the pancreas so that it may be released when required for protein digestion. The pancreas stores the inactive form trypsinogen because the active trypsin would cause severe damage to the tissue of the pancreas. Trypsinogen is released by the pancreas into the second part of the duodenum, via the pancreatic duct, along with other digestive enzymes.
Activation of trypsinogen
Trypsinogen is activated by enteropeptidase (also known as enterokinase). Enteropeptidase is produced by the mucosa of duodenum and it cleaves the peptide bond of trypsinogen after residue 15, which is a lysine. The N-terminal peptide is discarded, and a slight rearrangement of the folded protein occurs. The newly formed N-terminal residue (residue 16) inserts into a cleft, where its α-amino group forms an ion pair with the aspartate near the active site serine, and results in the conformational rearrang |
https://en.wikipedia.org/wiki/Melanopsin | Melanopsin is a type of photopigment belonging to a larger family of light-sensitive retinal proteins called opsins and encoded by the gene Opn4. In the mammalian retina, there are two additional categories of opsins, both involved in the formation of visual images: rhodopsin and photopsin (types I, II, and III) in the rod and cone photoreceptor cells, respectively.
In humans, melanopsin is found in intrinsically photosensitive retinal ganglion cells (ipRGCs). It is also found in the iris of mice and primates. Melanopsin is also found in rats, amphioxus, and other chordates. ipRGCs are photoreceptor cells which are particularly sensitive to the absorption of short-wavelength (blue) visible light and communicate information directly to the area of the brain called the suprachiasmatic nucleus (SCN), also known as the central "body clock", in mammals. Melanopsin plays an important non-image-forming role in the setting of circadian rhythms as well as other functions. Mutations in the Opn4 gene can lead to clinical disorders, such as Seasonal Affective Disorder (SAD). According to one study, melanopsin has been found in eighteen sites in the human brain (outside the retinohypothalamic tract), intracellularly, in a granular pattern, in the cerebral cortex, the cerebellar cortex and several phylogenetically old regions, primarily in neuronal soma, not in nuclei. Melanopsin is also expressed in human cones. However, only 0.11% to 0.55% of human cones express melanopsin and are exclu |
https://en.wikipedia.org/wiki/Photoelectrochemical%20cell | A "photoelectrochemical cell" is one of two distinct classes of device. The first produces electrical energy similarly to a dye-sensitized photovoltaic cell, which meets the standard definition of a photovoltaic cell. The second is a photoelectrolytic cell, that is, a device which uses light incident on a photosensitizer, semiconductor, or aqueous metal immersed in an electrolytic solution to directly cause a chemical reaction, for example to produce hydrogen via the electrolysis of water.
Both types of device are varieties of solar cell, in that a photoelectrochemical cell's function is to use the photoelectric effect (or, very similarly, the photovoltaic effect) to convert electromagnetic radiation (typically sunlight) either directly into electrical power, or into something which can itself be easily used to produce electrical power (hydrogen, for example, can be burned to create electrical power, see photohydrogen).
Two principles
The standard photovoltaic effect, as operating in standard photovoltaic cells, involves the excitation of negative charge carriers (electrons) within a semiconductor medium, and it is negative charge carriers (free electrons) which are ultimately extracted to produce power. The classification of photoelectrochemical cells which includes Grätzel cells meets this narrow definition, albeit the charge carriers are often excitonic.
The situation within a photoelectrolytic cell, on the other hand, is quite different. For example, in a water- |
https://en.wikipedia.org/wiki/Polyclonal%20antibodies | Polyclonal antibodies (pAbs) are antibodies that are secreted by different B cell lineages within the body (whereas monoclonal antibodies come from a single cell lineage). They are a collection of immunoglobulin molecules that react against a specific antigen, each identifying a different epitope.
Production
The general procedure to produce polyclonal antibodies is as follows:
Antigen preparation
Adjuvant selection and preparation
Animal selection
Injection process
Blood serum extraction
An antigen/adjuvant conjugate is injected into an animal of choice to initiate an amplified immune response. After a series of injections over a specific length of time, the animal is expected to have created antibodies against the conjugate. Blood is then extracted from the animal and then purified to obtain the antibody of interest.
Inoculation is performed on a suitable mammal, such as a mouse, rabbit or goat. Larger mammals are often preferred as the amount of serum that can be collected is greater. An antigen is injected into the mammal. This induces the B-lymphocytes to produce IgG immunoglobulins specific for the antigen. This polyclonal IgG is purified from the mammal's serum.
By contrast, monoclonal antibodies are derived from a single cell line.
Many methodologies exist for polyclonal antibody production in laboratory animals. Institutional guidelines governing animal use and procedures relating to these methodologies are generally oriented around humane considerations and |
https://en.wikipedia.org/wiki/Si%C3%B3 | The Sió or Sió-csatorna (Sió-Channel) is a fully regulated river in midwest Hungary. It is the outlet, at the eastern end, of Lake Balaton, flowing out of the lake in Siófok. It flows into the river Danube near the city of Szekszárd. Sió flows through the Hungarian counties Somogy, Fejér and Tolna, its main tributaries are Kapos from the right and Sárvíz from the left. It is long and its basin size is . The drainage basin of Sió (including Balaton) covers more than a third of Transdanubia. Its average discharge at the mouth is .
References
Rivers of Hungary |
https://en.wikipedia.org/wiki/Motorola%2068HC12 | The 68HC12 (6812 or HC12 for short) is a microcontroller family from Freescale Semiconductor. Originally introduced in the mid-1990s, the architecture is an enhancement of the Freescale 68HC11. Programs written for the HC11 are usually compatible with the HC12, which has a few extra instructions. The first 68HC12 derivatives had a maximum bus speed of 8 MHz and flash memory sizes up to 128 KB.
Architecture of the 68HC12
Like the 68HC11, the 68HC12 has two 8-bit accumulators A and B (referred to as a single 16-bit accumulator, D, when A & B are cascaded so as to allow for operations involving 16 bits), two 16-bit registers X and Y, a 16-bit program counter, a 16-bit stack pointer and an 8-bit Condition Code Register. Unlike the 68HC11 the processor has 16bit internal data paths
The 68HC12 adds to and replaces a small number of 68HC11 instructions with new forms that are closer to the 6809 processor. More significantly it changes the instruction encodings to be far more dense and adds many 6809 like indexing features, some with even more flexibility. The net result is that code sizes are typically 30% smaller.
HCS12/MC9S12 derivatives
Beginning in 2000 the family was extended with the introduction of the MC9S12 derivatives which have bus speeds of up to 25 MHz and flash sizes up to 512 KB.
The MC9S12NE64 was introduced by Freescale in September 2004, claiming to be the "industry's first single-chip fast-Ethernet Flash microcontroller." It features a 25 MHz HCS12 CPU, 64 KB |
https://en.wikipedia.org/wiki/Mixed%20inhibition | Mixed inhibition is a type of enzyme inhibition in which the inhibitor may bind to the enzyme whether or not the enzyme has already bound the substrate but has a greater affinity for one state or the other. It is called "mixed" because it can be seen as a conceptual "mixture" of competitive inhibition, in which the inhibitor can only bind the enzyme if the substrate has not already bound, and uncompetitive inhibition, in which the inhibitor can only bind the enzyme if the substrate has already bound. If the ability of the inhibitor to bind the enzyme is exactly the same whether or not the enzyme has already bound the substrate, it is known as a non-competitive inhibitor. Non-competitive inhibition is sometimes thought of as a special case of mixed inhibition.
In mixed inhibition, the inhibitor binds to an allosteric site, i.e. a site different from the active site where the substrate binds. However, not all inhibitors that bind at allosteric sites are mixed inhibitors.
Mixed inhibition may result in either:
A decrease in the apparent affinity of the enzyme for the substrate (Km value appears to increase; ) -- seen in cases where the inhibitor favours binding to the free enzyme. More closely mimics competitive binding.
An increase in the apparent affinity of the enzyme for the substrate (Km value appears to decrease; ) -- seen in cases where the inhibitor favours binding to the enzyme-substrate complex. More closely mimics uncompetitive binding.
In either case the inhib |
https://en.wikipedia.org/wiki/Dry%20etching | Dry etching refers to the removal of material, typically a masked pattern of semiconductor material, by exposing the material to a bombardment of ions (usually a plasma of reactive gases such as fluorocarbons, oxygen, chlorine, boron trichloride; sometimes with addition of nitrogen, argon, helium and other gases) that dislodge portions of the material from the exposed surface. A common type of dry etching is reactive-ion etching. Unlike with many (but not all, see isotropic etching) of the wet chemical etchants used in wet etching, the dry etching process typically etches directionally or anisotropically.
Applications
Dry etching is used in conjunction with photolithographic techniques to attack certain areas of a semiconductor surface in order to form recesses in material.
Applications include contact holes (which are contacts to the underlying semiconductor substrate), via holes (which are holes that are formed to provide an interconnect path between conductive layers in the layered semiconductor device), transistor gates for FinFET technology, or to otherwise remove portions of semiconductor layers where predominantly vertical sides are desired. Along with semiconductor manufacturing, micromachining and display production, the removal of organic residues by oxygen plasmas is sometimes correctly described as a dry etch process. The term plasma ashing can be used instead.
Dry etching is particularly useful for materials and semiconductors which are chemically resistant |
https://en.wikipedia.org/wiki/Wolstenholme%27s%20theorem | In mathematics, Wolstenholme's theorem states that for a prime number , the congruence
holds, where the parentheses denote a binomial coefficient. For example, with p = 7, this says that 1716 is one more than a multiple of 343. The theorem was first proved by Joseph Wolstenholme in 1862. In 1819, Charles Babbage showed the same congruence modulo p2, which holds for . An equivalent formulation is the congruence
for , which is due to Wilhelm Ljunggren (and, in the special case , to J. W. L. Glaisher) and is inspired by Lucas' theorem.
No known composite numbers satisfy Wolstenholme's theorem and it is conjectured that there are none (see below). A prime that satisfies the congruence modulo p4 is called a Wolstenholme prime (see below).
As Wolstenholme himself established, his theorem can also be expressed as a pair of congruences for (generalized) harmonic numbers:
(Congruences with fractions make sense, provided that the denominators are coprime to the modulus.)
For example, with p=7, the first of these says that the numerator of 49/20 is a multiple of 49, while the second says the numerator of 5369/3600 is a multiple of 7.
Wolstenholme primes
A prime p is called a Wolstenholme prime iff the following condition holds:
If p is a Wolstenholme prime, then Glaisher's theorem holds modulo p4. The only known Wolstenholme primes so far are 16843 and 2124679 ; any other Wolstenholme prime must be greater than 109. This result is consistent with the heuristic argument that |
https://en.wikipedia.org/wiki/Instruction%20scheduling | In computer science, instruction scheduling is a compiler optimization used to improve instruction-level parallelism, which improves performance on machines with instruction pipelines. Put more simply, it tries to do the following without changing the meaning of the code:
Avoid pipeline stalls by rearranging the order of instructions.
Avoid illegal or semantically ambiguous operations (typically involving subtle instruction pipeline timing issues or non-interlocked resources).
The pipeline stalls can be caused by structural hazards (processor resource limit), data hazards (output of one instruction needed by another instruction) and control hazards (branching).
Data hazards
Instruction scheduling is typically done on a single basic block. In order to determine whether rearranging the block's instructions in a certain way preserves the behavior of that block, we need the concept of a data dependency. There are three types of dependencies, which also happen to be the three data hazards:
Read after Write (RAW or "True"): Instruction 1 writes a value used later by Instruction 2. Instruction 1 must come first, or Instruction 2 will read the old value instead of the new.
Write after Read (WAR or "Anti"): Instruction 1 reads a location that is later overwritten by Instruction 2. Instruction 1 must come first, or it will read the new value instead of the old.
Write after Write (WAW or "Output"): Two instructions both write the same location. They must occur in their original |
https://en.wikipedia.org/wiki/Acepromazine | Acepromazine, acetopromazine, or acetylpromazine (commonly known as ACP, Ace, or by the trade names Atravet or Acezine 2, number depending on mg/ml dose) is a phenothiazine derivative antipsychotic drug. It was used in humans during the 1950s as an antipsychotic, but is now almost exclusively used on animals as a sedative and antiemetic. A closely related analogue, chlorpromazine, is still used in humans.
The standard pharmaceutical preparation, acepromazine maleate, is used in veterinary medicine in dogs and cats. It is used widely in horses as a pre-anesthetic sedative and has been shown to reduce anesthesia related death. However, it should be used with caution (but is not absolutely contraindicated) in stallions due to the risk of paraphimosis and priapism. Its potential for cardiac effects can be profound, namely hypotension due to peripheral vasodilation, so it should be avoided or used with caution in geriatric or debilitated animals.
Pharmacology
The clinical pharmacology of acepromazine is similar to that of other phenothiazine derived anti-psychotic agents. The primary behavioral effects are attributed to its potent antagonism of post-synaptic D2 receptors and, to a lesser degree, the other D2-like receptors. Additional effects are related to its appreciable antagonistic effects on various other receptors, including the α1-adrenergic receptors, H1 receptors, and muscarinic acetylcholine receptors. It is metabolized by the liver, oxidized to produce its primary met |
https://en.wikipedia.org/wiki/Niedervogelgesang | Niedervogelgesang is a village in the municipality of Pirna, in Saxony, Germany. It was incorporated into Pirna in 1923. The place was mentioned for the first time in 1551. It is situated on the left bank of the river Elbe, 3 km east of Pirna town centre. Its name translates as "lower bird song."
References
Pirna |
https://en.wikipedia.org/wiki/Rottwerndorf | Rottwerndorf is a village in the municipality of Pirna, in Saxony, Germany. It was incorporated into Pirna in 1923. The place was mentioned for the first time in 1337. It is situated on the river Gottleuba, south of Pirna town centre.
The village was characterized by quarryman and agriculture.
There is a Renaissance-era castle from the 16th century in the village.
References
Pirna
Populated places in Saxon Switzerland |
https://en.wikipedia.org/wiki/MyoD | MyoD, also known as myoblast determination protein 1, is a protein in animals that plays a major role in regulating muscle differentiation. MyoD, which was discovered in the laboratory of Harold M. Weintraub, belongs to a family of proteins known as myogenic regulatory factors (MRFs). These bHLH (basic helix loop helix) transcription factors act sequentially in myogenic differentiation. Vertebrate MRF family members include MyoD1, Myf5, myogenin, and MRF4 (Myf6). In non-vertebrate animals, a single MyoD protein is typically found.
MyoD is one of the earliest markers of myogenic commitment. MyoD is expressed at extremely low and essentially undetectable levels in quiescent satellite cells, but expression of MyoD is activated in response to exercise or muscle tissue damage. The effect of MyoD on satellite cells is dose-dependent; high MyoD expression represses cell renewal, promotes terminal differentiation and can induce apoptosis. Although MyoD marks myoblast commitment, muscle development is not dramatically ablated in mouse mutants lacking the MyoD gene. This is likely due to functional redundancy from Myf5 and/or Mrf4. Nevertheless, the combination of MyoD and Myf5 is vital to the success of myogenesis.
History
MyoD was cloned by a functional assay for muscle formation reported in Cell in 1987 by Davis, Weintraub, and Lassar. It was first described as a nuclear phosphoprotein in 1988 by Tapscott, Davis, Thayer, Cheng, Weintraub, and Lassar in Science. The researchers ex |
https://en.wikipedia.org/wiki/Tallgrass%20prairie | The tallgrass prairie is an ecosystem native to central North America. Historically, natural and anthropogenic fire, as well as grazing by large mammals (primarily bison) provided periodic disturbances to these ecosystems, limiting the encroachment of trees, recycling soil nutrients, and facilitating seed dispersal and germination. Prior to widespread use of the steel plow, which enabled large scale conversion to agricultural land use, tallgrass prairies extended throughout the American Midwest and smaller portions of southern central Canada, from the transitional ecotones out of eastern North American forests, west to a climatic threshold based on precipitation and soils, to the southern reaches of the Flint Hills in Oklahoma, to a transition into forest in Manitoba.
They were characteristically found in the central forest-grasslands transition, the central tall grasslands, the upper Midwest forest-savanna transition, and the northern tall grasslands ecoregions. They flourished in areas with rich loess soils and moderate rainfall around 30-35 inches (700–900 mm) per year. To the east were the fire-maintained eastern savannas. In the northeast, where fire was infrequent and periodic windthrow represented the main source of disturbance, beech-maple forests dominated. In contrast, shortgrass prairie was typical in the western Great Plains, where rainfall is less frequent, and soils are less fertile. Due to expansive agricultural land use, very little tallgrass prairie remains. |
https://en.wikipedia.org/wiki/GSK-3 | Glycogen synthase kinase 3 (GSK-3) is a serine/threonine protein kinase that mediates the addition of phosphate molecules onto serine and threonine amino acid residues. First discovered in 1980 as a regulatory kinase for its namesake, glycogen synthase (GS), GSK-3 has since been identified as a protein kinase for over 100 different proteins in a variety of different pathways. In mammals, including humans, GSK-3 exists in two isozymes encoded by two homologous genes GSK-3α (GSK3A) and GSK-3β (GSK3B). GSK-3 has been the subject of much research since it has been implicated in a number of diseases, including type 2 diabetes, Alzheimer's disease, inflammation, cancer, addiction and bipolar disorder.
GSK-3 is a serine/threonine protein kinase that phosphorylate either threonine or serine, and this phosphorylation controls a variety of biological activities, such as glycogen metabolism, cell signaling, cellular transport, and others. GS inhibition by GSK-3β leads to a decrease in glycogen synthesis in the liver and muscles, along with increased blood glucose or hyperglycemia. This is why GSK-3β is associated with the pathogenesis and progression of many diseases, such as diabetes, obesity, cancer, and Alzheimer's disease. It is active in resting cells and is inhibited by several hormones such as insulin, endothelial growth factor, and platelet-derived growth factor. Insulin inactivates it by phosphorylation of the specific serine residues Ser21 and Ser9 in GSK-3 isoforms α and β, |
https://en.wikipedia.org/wiki/Hurwitz%27s%20automorphisms%20theorem | In mathematics, Hurwitz's automorphisms theorem bounds the order of the group of automorphisms, via orientation-preserving conformal mappings, of a compact Riemann surface of genus g > 1, stating that the number of such automorphisms cannot exceed 84(g − 1). A group for which the maximum is achieved is called a Hurwitz group, and the corresponding Riemann surface a Hurwitz surface. Because compact Riemann surfaces are synonymous with non-singular complex projective algebraic curves, a Hurwitz surface can also be called a Hurwitz curve. The theorem is named after Adolf Hurwitz, who proved it in .
Hurwitz's bound also holds for algebraic curves over a field of characteristic 0, and over fields of positive characteristic p>0 for groups whose order is coprime to p, but can fail over fields of positive characteristic p>0 when p divides the group order. For example, the double cover of the projective line y2 = xp −x branched at all points defined over the prime field has genus g=(p−1)/2 but is acted on by the group SL2(p) of order p3−p.
Interpretation in terms of hyperbolicity
One of the fundamental themes in differential geometry is a trichotomy between the Riemannian manifolds of positive, zero, and negative curvature K. It manifests itself in many diverse situations and on several levels. In the context of compact Riemann surfaces X, via the Riemann uniformization theorem, this can be seen as a distinction between the surfaces of different topologies:
X a sphere, a compac |
https://en.wikipedia.org/wiki/Sovereign%20State%20of%20Aeterna%20Lucina | The Sovereign State of Aeterna Lucina (also known as the Sovereign Humanitarian Mission State of Aeterna Lucina), was an Australian micronation. It was founded in 1978, and continued until the death of its founder.
The founder and "Supreme Lord" of Aeterna Lucina was German migrant Paul Neuman, who changed his name by deed poll to Paul Baron Neuman. He founded it when living in Byron Bay, and later moved it with him to Curl Curl in Sydney, and finally Cooma. He claimed to have received the title Baron Neuman of Kara Bagh from the exiled former king Hassan III of Afghanistan and also claimed to have been awarded hundreds of other honours, including professorships, Doctorates of Philosophy, and degrees in divinity. He sold at least one "knighthood".
Aeterna Lucina came to public attention in 1990 when Neuman faced fraud charges in the New South Wales court system relating to land sale offences. The case involved A$144,000 and was eventually abandoned in 1992.
See also
List of micronations
References
Former unrecognized countries
Micronations
1970s establishments in Australia
Micronations in Australia |
https://en.wikipedia.org/wiki/Polygonatum | Polygonatum , also known as King Solomon's-seal or Solomon's seal, is a genus of flowering plants. In the APG III classification system, it is placed in the family Asparagaceae, subfamily Nolinoideae (formerly the family Ruscaceae). It has also been classified in the former family Convallariaceae and, like many lilioid monocots, was formerly classified in the lily family, Liliaceae. The genus is distributed throughout the temperate Northern Hemisphere. Most of the approximately 63 species occur in Asia, with 20 endemic to China.
Etymology
Polygonatum comes from the ancient Greek for "many knees", referring to the multiple jointed rhizome. One explanation for the derivation of the common name "Solomon's seal" is that the roots bear depressions which resemble royal seals. Another is that the cut roots resemble Hebrew characters.
Description
The fruits are red or black berries. The berries may be poisonous to humans.
Taxonomy
Species
The following species are recognised in the genus Polygonatum:
Polygonatum acuminatifolium
Polygonatum adnatum
Polygonatum amabile
Polygonatum angelicum
Polygonatum annamense
Polygonatum arisanense
Polygonatum autumnale
Polygonatum × azegamii
Polygonatum biflorum (including Polygonatum commutatum) – Solomon's seal, smooth or great Solomon's seal – Eastern and central North America
Polygonatum brevistylum
Polygonatum × buschianum
Polygonatum campanulatum
Polygonatum cathcartii
Polygonatum cirrhifolium – tendril-leaf Solomon's seal |
https://en.wikipedia.org/wiki/British%20Rail%20locomotive%20and%20multiple%20unit%20numbering%20and%20classification | A number of different numbering and classification schemes were used for locomotives and multiple units operated by British Railways (BR), and this page explains the principal systems. This section also covers the post-privatisation period, as the broad numbering and classification arrangements have not altered since the break-up of BR.
Locomotives and multiple units (the majority being self-propelled) have frequently had similar arrangements for classification and numbering, so are considered together here. There are also links to other pages that deal in greater depth with the particulars of individual types.
Constituent companies
In 1948, BR inherited a variety of locomotives and multiple units from the Big Four railway companies and some smaller concerns. Details of the numbering and classification systems used by the Big Four companies are covered in the following pages:
Great Western Railway: GWR locomotive numbering and classification
Southern Railway: SR locomotive numbering and classification and SR multiple unit numbering and classification
London, Midland and Scottish Railway: LMS locomotive numbering and classification
London and North Eastern Railway: LNER locomotive numbering and classification
In the main, new locomotives and multiple units built by BR to pre-nationalisation designs were numbered and classified according to the principles applied by the relevant Big Four company.
1948 numbering and classification
Immediately after nationalisation, BR ha |
https://en.wikipedia.org/wiki/Antimony%20trisulfide | Antimony trisulfide () is found in nature as the crystalline mineral stibnite and the amorphous red mineral (actually a mineraloid) metastibnite. It is manufactured for use in safety matches, military ammunition, explosives and fireworks. It also is used in the production of ruby-colored glass and in plastics as a flame retardant. Historically the stibnite form was used as a grey pigment in paintings produced in the 16th century. In 1817, the dye and fabric chemist, John Mercer discovered the non-stoichiometric compound Antimony Orange (approximate formula ), the first good orange pigment available for cotton fabric printing.
Antimony trisulfide was also used as the image sensitive photoconductor in vidicon camera tubes. It is a semiconductor with a direct band gap of 1.8–2.5 eV. With suitable doping, p and n type materials can be produced.
Preparation and reactions
can be prepared from the elements at temperature 500–900 °C:
is precipitated when is passed through an acidified solution of Sb(III). This reaction has been used as a gravimetric method for determining antimony, bubbling through a solution of Sb(III) compound in hot HCl deposits an orange form of which turns black under the reaction conditions.
is readily oxidised, reacting vigorously with oxidising agents. It burns in air with a blue flame. It reacts with incandescence with cadmium, magnesium and zinc chlorates. Mixtures of and chlorates may explode.
In the extraction of antimony from antimony ores t |
https://en.wikipedia.org/wiki/Sellaite | Sellaite is a magnesium fluoride mineral with the formula MgF2. It crystallizes in the tetragonal crystal system, typically as clear to white vitreous prisms. It may be fibrous and occur as radiating aggregates. It has a Mohs hardness of 5 to 6 and a specific gravity of 2.97 to 3.15. Refractive index values are nω = 1.378 and nε = 1.390.
Discovery and occurrence
Sellaite was first described in 1868 and named for Italian mining engineer and mineralogist Quintino Sella (1827–1884). Its type locality is the in France, where it occurred inside bitumen-bearing dolomite-anhydrite clasts within a moraine deposit. It has been reported in an evaporite deposit at Bleicherode; within volcanic ejecta and fumaroles at Vesuvius; in a metamorphic magnesite deposit at ; and in sodic alkali granite near .
References
Palache, C., H. Berman, and C. Frondel (1951) Dana’s system of mineralogy, (7th edition), v. II, pp. 37–39
Magnesium minerals
Fluorine minerals
Tetragonal minerals
Minerals in space group 136 |
https://en.wikipedia.org/wiki/Azo%20compound | Azo compounds are organic compounds bearing the functional group diazenyl (, in which R and R′ can be either aryl or alkyl groups).
IUPAC defines azo compounds as: "Derivatives of diazene (diimide), , wherein both hydrogens are substituted by hydrocarbyl groups, e.g. azobenzene or diphenyldiazene." The more stable derivatives contain two aryl groups. The group is called an azo group (, ).
Many textile and leather articles are dyed with azo dyes and pigments.
Aryl azo compounds
Aryl azo compounds are usually stable, crystalline species. Azobenzene is the prototypical aromatic azo compound. It exists mainly as the trans isomer, but upon illumination, converts to the cis isomer.
Aromatic azo compounds can be synthesized by azo coupling, which entails an electrophilic substitution reaction where an aryl diazonium cation is attacked by another aryl ring, especially those substituted with electron-donating groups:
ArN2+ + Ar'H -> ArN=NAr' + H+
Since diazonium salts are often unstable near room temperature, the azo coupling reactions are typically conducted near 0 °C. The oxidation of hydrazines () also gives azo compounds. Azo dyes are also prepared by the condensation of nitroaromatics with anilines followed by reduction of the resulting azoxy intermediate:
ArNO2 + Ar'NH2 -> ArN(O)=NAr' + H2O
ArN(O)=NAr' + C6H12O6 -> ArN=NAr' + C6H10O6 + H2O
For textile dying, a typical nitro coupling partner would be disodium 4,4′-dinitrostilbene-2,2′-disulfonate. Typical aniline partner |
https://en.wikipedia.org/wiki/Zerna%20Sharp | Zerna Addas Sharp (August 12, 1889 – June 17, 1981) was an American educator and book editor who is best known as the creator of the Dick and Jane series of beginning readers for elementary school-aged children. Published by Scott, Foresman and Company of Chicago, Illinois, the readers, which described the activities of her fictional siblings, "Dick," "Jane," "Sally," and other characters, were widely used in schools in the United States and many other English-speaking countries for nearly forty years. The series, which included such titles as We Look and See, We Come and Go, We Work and Play, and Fun with Dick and Jane, among others, was marketed until 1973 and used the look-say method of teaching reading.
Early life and education
Zerna Addas Sharp was born on August 12, 1889, to Charles and Lottie (Smith) Sharp in Hillisburg, Clinton County, Indiana, and was the eldest of the family's five children. Zerna's father owned a general store in Hillisburg. After graduating from high school she completed a year of teacher training at Marion Normal College (Indiana Wesleyan University) in Marion, Indiana, but never earned a degree, and later attended Columbia University in New York City.
Career
Early years
Sharp began her career as an educator. She taught first-grade students for nearly a decade at elementary schools in Hillisburg, Kirklin, and La Porte, Indiana. Sharp also served as an elementary school principal.
Creator of the Dick and Jane readers
Sharp created the characte |
https://en.wikipedia.org/wiki/Kullback%E2%80%93Leibler%20divergence | In mathematical statistics, the Kullback–Leibler divergence (also called relative entropy and I-divergence), denoted , is a type of statistical distance: a measure of how one probability distribution is different from a second, reference probability distribution . A simple interpretation of the KL divergence of from is the expected excess surprise from using as a model when the actual distribution is . While it is a measure of how different two distributions are, and in some sense is thus a "distance", it is not actually a metric, which is the most familiar and formal type of distance. In particular, it is not symmetric in the two distributions (in contrast to variation of information), and does not satisfy the triangle inequality. Instead, in terms of information geometry, it is a type of divergence, a generalization of squared distance, and for certain classes of distributions (notably an exponential family), it satisfies a generalized Pythagorean theorem (which applies to squared distances).
In the simple case, a relative entropy of 0 indicates that the two distributions in question have identical quantities of information. Relative entropy is a nonnegative function of two distributions or measures. It has diverse applications, both theoretical, such as characterizing the relative (Shannon) entropy in information systems, randomness in continuous time-series, and information gain when comparing statistical models of inference; and practical, such as applied statisti |
https://en.wikipedia.org/wiki/Business%20ecosystem | Starting in the early 1990s, James F. Moore originated the strategic planning concept of a business ecosystem, now widely adopted in the high tech industry. The basic definition comes from Jim Moore's book, The Death of Competition: Leadership and Strategy in the Age of Business Ecosystems.
The origins of the concept
The concept first appeared in Moore's May/June 1993 Harvard Business Review article, titled "Predators and Prey: A New Ecology of Competition", and won the McKinsey Award for article of the year.
Moore defined "business ecosystem" as:
An economic community supported by a foundation of interacting organizations and individuals—the organisms of the business world. The economic community produces goods and services of value to customers, who are themselves members of the ecosystem. The member organisms also include suppliers, lead producers, competitors, and other stakeholders. Over time, they coevolve their capabilities and roles, and tend to align themselves with the directions set by one or more central companies. Those companies holding leadership roles may change over time, but the function of ecosystem leader is valued by the community because it enables members to move toward shared visions to align their investments, and to find mutually supportive roles.
Moore used several ecological metaphors, suggesting that the firm is embedded in a (business) environment, that it needs to coevolve with other companies, and that “the particular niche a business occup |
https://en.wikipedia.org/wiki/2-8-2 | Under the Whyte notation for the classification of steam locomotives, represents the wheel arrangement of two leading wheels on one axle, usually in a leading truck, eight powered and coupled driving wheels on four axles and two trailing wheels on one axle, usually in a trailing truck. This configuration of steam locomotive is most often referred to as a Mikado, frequently shortened to Mike.
It was also at times referred to on some railroads in the United States as the McAdoo Mikado and, during World War II, the MacArthur.
The notation 2-8-2T indicates a tank locomotive of this wheel arrangement, the "T" suffix indicating a locomotive on which the water is carried in tanks mounted on the engine rather than in an attached tender.
Overview
The 2-8-2 wheel arrangement allowed the locomotive's firebox to be placed behind instead of above the driving wheels, thereby allowing a larger firebox that could be both wide and deep. This supported a greater rate of combustion and thus a greater capacity for steam generation, allowing for more power at higher speeds. Allied with the larger driving wheel diameter which was possible when they did not impinge on the firebox, it meant that the 2-8-2 was capable of higher speeds than a with a heavy train. These locomotives did not suffer from the imbalance of reciprocating parts as much as did the 2-6-2 or the , because the center of gravity was between the second and third drivers instead of above the centre driver.
The first 2-8-2 locom |
https://en.wikipedia.org/wiki/Lesch%E2%80%93Nyhan%20syndrome | Lesch–Nyhan syndrome (LNS) is a rare inherited disorder caused by a deficiency of the enzyme hypoxanthine-guanine phosphoribosyltransferase (HGPRT). This deficiency occurs due to mutations in the HPRT1 gene located on the X chromosome. LNS affects about 1 in 380,000 live births. The disorder was first recognized and clinically characterized by American medical student Michael Lesch and his mentor, pediatrician William Nyhan, at Johns Hopkins.
The HGPRT deficiency causes a build-up of uric acid in all body fluids. The combination of increased synthesis and decreased utilization of purines leads to high levels of uric acid production. This results in both high levels of uric acid in the blood and urine, associated with severe gout and kidney problems. Neurological signs include poor muscle control and moderate intellectual disability. These complications usually appear in the first year of life. Beginning in the second year of life, a particularly striking feature of LNS is self-mutilating behaviors, characterized by lip and finger biting. Neurological symptoms include facial grimacing, involuntary writhing, and repetitive movements of the arms and legs similar to those seen in Huntington's disease. The cause of the neurological abnormalities remains unknown. Because a lack of HGPRT causes the body to poorly utilize vitamin B12, some males may develop megaloblastic anemia.
LNS is inherited in an X-linked recessive manner; the gene mutation is usually carried by the mother and |
https://en.wikipedia.org/wiki/Esmolol | Esmolol, sold under the brand name Brevibloc, is a cardio selective beta1 receptor blocker with rapid onset, a very short duration of action, and no significant intrinsic sympathomimetic or membrane stabilising activity at therapeutic dosages.
It is a class II antiarrhythmic. Esmolol decreases the force and rate of heart contractions by blocking beta-adrenergic receptors of the sympathetic nervous system, which are found in the heart and other organs of the body. Esmolol prevents the action of two naturally occurring substances: epinephrine and norepinephrine.
It was patented in 1980 and approved for medical use in 1987.
Medical uses
To terminate supraventricular tachycardia,
Episodic atrial fibrillation or flutter,
Arrhythmia during anaesthesia,
To reduce HR and BP during and after cardiac surgery, and
In early treatment of myocardial infarction.
Esmolol is also used in blunting the hemodynamic response to laryngoscopy and intubation.
Pharmacology
Pharmacodynamics
Esmolol is a beta blocker, or an antagonist of the β-adrenergic receptors. It is selective for the β1-adrenergic receptor and has no intrinsic sympathomimetic activity.
Pharmacokinetics
Esmolol is considered a soft drug, one that is rapidly metabolized to an inactive form. Esmolol is rapidly metabolized by hydrolysis of the ester linkage, chiefly by the esterases in the cytosol of red blood cells and not by plasma cholinesterases or red cell membrane acetylcholinesterase. Total body clearance in man wa |
https://en.wikipedia.org/wiki/CKNW | CKNW is a news/talk formatted radio station in Vancouver, British Columbia, owned by Corus Entertainment. It broadcasts on an assigned frequency of AM 980 kHz, and is unusual in that it is a 50,000-watt, Class A station broadcasting on a regional (not clear-channel) frequency. CKNW uses a four-tower directional antenna from a site near Surrey, while its studios are located at TD Tower in Downtown Vancouver.
History
CKNW began in New Westminster, British Columbia, on August 15, 1944, at its original frequency of 1230 AM, under the ownership of Bill Rea's International Broadcasting Company. It was Vancouver's first country station, the first in the region to provide hourly newscasts (between 6:00 a.m. and midnight) and the first in the province to broadcast 24 hours a day, beginning in 1947.
In 1947, Rea purchased a half-interest in Port Alberni radio station CJAV. Several personalities who started there would move to CKNW. These included Joe Chesney, who became morning show host until moving on to establish Langley station CJJC (now CKST in Vancouver) in 1963, and Jim Robson, who would provide play-by-play for the newly established Vancouver Canucks of the NHL beginning in 1970. On January 2, 1949, CKNW switched frequencies to 1320 AM and increased its power from 250 watts to 1,000. The station again increased power to 5,000 watts on November 5, 1954.
Jack Webster advanced talk-show radio methods during his time with CKNW in the 1960s.
WIC ownership
In February 1956, Bill |
https://en.wikipedia.org/wiki/4ZZZ | 4ZZZ (pronounced "Four Triple Zed" or simply "Triple Zed") is an independent community radio station operating in Brisbane, Australia at the frequency 102.1 FM. As a community radio station, 4ZZZ is a member of the Community Broadcasting Association of Australia (CBAA). The station broadcasts to much of South East Queensland, parts of northern New South Wales and web streams from its website.
History
4ZZZ was established to provide a radical alternative to mainstream news, to promote a sense of engagement and activism in community life and to promote Australian music. The station began transmission on 8 December 1975 as 4ZZ at 105.7 MHz, the first FM community broadcaster in Brisbane transmitting in stereo.
The station's first studios were constructed by announcing staff and volunteers, using second-hand building materials and furniture. The first transmitter was hand built by the station engineer Ross Dannecker with help from Dave Aberdeen. Founders included activist, Jim Beatson, journalist Marian Wilkinson, Arts Administrator, John Stanwell and academic Alan Knight. Announcer John Woods launched the station with The Who's "Won't Get Fooled Again" at Midday 8 December 1975 (a month after The Dismissal). Along with 2JJJ and 3RRR, 4ZZZ has been a major promoter of independent and alternative music providing exposure for many Australian and international artists. Through the late 1970s and early 1980s the station also produced many groundbreaking and award-winning features a |
https://en.wikipedia.org/wiki/Tarantul-class%20corvette | The Soviet designation Project 1241 Molniya () are a class of Russian missile corvettes (large missile cutters in Soviet classification). They have the NATO reporting name Tarantul (not to be confused with the , whose official Soviet name is also Project 205P Tarantul). These ships were designed to replace the Project 205M Tsunami missile cutter (NATO: ).
Development
In the late 1970s, the Soviets realised the need for a larger, more seaworthy craft with better gun armament and higher positioned air search radars. The need for these improvements was underscored by the First Gulf War, when 12 Iraqi Osa-I-class missile boats were destroyed or damaged by short ranged Sea Skua anti-ship missiles. They were attacked by British Lynx helicopters, but the Osa crews did not notice them because they flew below their radar horizon. In the Tarantul class, both the single main gun and the two Gatling-type guns are used for air defence, together with a comprehensive electronic warfare suite. The boats are built by the Petrovsky yard (St. Petersburg), Rybinsk and Ulis yard (Vladivostok). A version of these ships for coastal anti-submarine warfare and patrol was developed as the or Project 1241.2. The Indian Navy paid approximately $30 million each to license-produce Tarantul-I in the early 1990s. With over 30 sales on the export market the Tarantul has been a relative success for the Russian shipbuilding industry.
Versions
Project 1241.1 (NATO: Tarantul-II)
The naming convention for |
https://en.wikipedia.org/wiki/Type-2%20Gumbel%20distribution | In probability theory, the Type-2 Gumbel probability density function is
for
.
For the mean is infinite. For the variance is infinite.
The cumulative distribution function is
The moments exist for
The distribution is named after Emil Julius Gumbel (1891 – 1966).
Generating random variates
Given a random variate U drawn from the uniform distribution in the interval (0, 1), then the variate
has a Type-2 Gumbel distribution with parameter and . This is obtained by applying the inverse transform sampling-method.
Related distributions
The special case b = 1 yields the Fréchet distribution.
Substituting and yields the Weibull distribution. Note, however, that a positive k (as in the Weibull distribution) would yield a negative a and hence a negative probability density, which is not allowed.
Based on The GNU Scientific Library, used under GFDL.
See also
Extreme value theory
Gumbel distribution
Continuous distributions |
https://en.wikipedia.org/wiki/Dirichlet%20distribution | In probability and statistics, the Dirichlet distribution (after Peter Gustav Lejeune Dirichlet), often denoted , is a family of continuous multivariate probability distributions parameterized by a vector of positive reals. It is a multivariate generalization of the beta distribution, hence its alternative name of multivariate beta distribution (MBD). Dirichlet distributions are commonly used as prior distributions in Bayesian statistics, and in fact, the Dirichlet distribution is the conjugate prior of the categorical distribution and multinomial distribution.
The infinite-dimensional generalization of the Dirichlet distribution is the Dirichlet process.
Definitions
Probability density function
The Dirichlet distribution of order K ≥ 2 with parameters α1, ..., αK > 0 has a probability density function with respect to Lebesgue measure on the Euclidean space RK-1 given by
where belong to the standard simplex, or in other words:
The normalizing constant is the multivariate beta function, which can be expressed in terms of the gamma function:
Support
The support of the Dirichlet distribution is the set of K-dimensional vectors whose entries are real numbers in the interval [0,1] such that , i.e. the sum of the coordinates is equal to 1. These can be viewed as the probabilities of a K-way categorical event. Another way to express this is that the domain of the Dirichlet distribution is itself a set of probability distributions, specifically the set of K-dimensional |
https://en.wikipedia.org/wiki/Landau%20distribution | In probability theory, the Landau distribution is a probability distribution named after Lev Landau.
Because of the distribution's "fat" tail, the moments of the distribution, like mean or variance, are undefined. The distribution is a particular case of stable distribution.
Definition
The probability density function, as written originally by Landau, is defined by the complex integral:
where a is an arbitrary positive real number, meaning that the integration path can be any parallel to the imaginary axis, intersecting the real positive semi-axis, and refers to the natural logarithm.
In other words it is the Laplace transform of the function .
The following real integral is equivalent to the above:
The full family of Landau distributions is obtained by extending the original distribution to a location-scale family of stable distributions with parameters and , with characteristic function:
where and , which yields a density function:
Taking and we get the original form of above.
Properties
Translation: If then .
Scaling: If then .
Sum: If and then .
These properties can all be derived from the characteristic function.
Together they imply that the Landau distributions are closed under affine transformations.
Approximations
In the "standard" case and , the pdf can be approximated using Lindhard theory which says:
where is Euler's constant.
A similar approximation of for and is:
Related distributions
The Landau distribution is a stable distribu |
https://en.wikipedia.org/wiki/Stable%20distribution | In probability theory, a distribution is said to be stable if a linear combination of two independent random variables with this distribution has the same distribution, up to location and scale parameters. A random variable is said to be stable if its distribution is stable. The stable distribution family is also sometimes referred to as the Lévy alpha-stable distribution, after Paul Lévy, the first mathematician to have studied it.
Of the four parameters defining the family, most attention has been focused on the stability parameter, (see panel). Stable distributions have , with the upper bound corresponding to the normal distribution, and to the Cauchy distribution. The distributions have undefined variance for , and undefined mean for . The importance of stable probability distributions is that they are "attractors" for properly normed sums of independent and identically distributed (iid) random variables. The normal distribution defines a family of stable distributions. By the classical central limit theorem the properly normed sum of a set of random variables, each with finite variance, will tend toward a normal distribution as the number of variables increases. Without the finite variance assumption, the limit may be a stable distribution that is not normal. Mandelbrot referred to such distributions as "stable Paretian distributions", after Vilfredo Pareto. In particular, he referred to those maximally skewed in the positive direction with as "Pareto–Lévy distribut |
https://en.wikipedia.org/wiki/Wardite | Wardite is a hydrous sodium aluminium phosphate hydroxide mineral with formula: NaAl3(PO4)2(OH)4·2(H2O). Wardite is of interest for its rare crystallography. It crystallizes in the tetragonal trapezohedral class and is one of only a few minerals in that class. Wardite forms vitreous green to bluish green to white to colorless crystals, masses, and fibrous encrustations. It has a Mohs hardness of 5 and a specific gravity of 2.81–2.87.
Occurrence
It occurs with variscite in phosphate nodules and occurs uncommonly in pegmatites and phosphate deposits through alteration of amblygonite.
Wardite was named for Henry Augustus Ward (1834–1906) of the University of Rochester in New York. It first described in 1896 for an occurrence in Clay Canyon, Fairfield, Utah County, Utah, US. Though rare it has been reported from many locations worldwide.
See also
List of minerals
List of minerals named after people
References
Mineral galleries
Sodium minerals
Aluminium minerals
Phosphate minerals
Tetragonal minerals
Minerals in space group 92 |
https://en.wikipedia.org/wiki/Campylite | Campylite is a variety of the lead arsenate mineral mimetite which received the name from the Greek 'kampylos'- bent, on account of the barrel-shaped bend of its crystals. It has also been used as an alternate name for pyromorphite.
It occurs in the upper lead deposits through the oxidation of galena or cerussite. The main deposits are Příbram in Bohemia and Dry Gill, Caldbeck Fells, near Wigton, Cumbria, England.
References
Mindat with location data
Webmineral pyromorphite page
Further reading
Mick Cooper and Chris Stanley, 1990, Minerals of the English Lake District, Natural History Museum Publications, London,
Lead minerals
Arsenate minerals |
https://en.wikipedia.org/wiki/Zippeite | Zippeite is a hydrous potassium uranium sulfate mineral with formula: K4(UO2)6(SO4)3(OH)10·4(H2O). It forms yellow to reddish brown monoclinic-prismatic crystals with perfect cleavage. The typical form is as encrustations and pulverulent earthy masses. It forms as efflorescent encrustations in underground uranium mines. It has a Mohs hardness of 2 and a specific gravity of 3.66. It is strongly fluorescent yellow under ultraviolet light and is moderately radioactive.
Historical usage
A mineral which caught the attention of a Bohemian metallurgist, Adolf Patera, in the 1850s by its striking colour. It was named after the Austrian mineralogist Franz Xaver Maximilian Zippe (1791–1863). This was during the period when the fame of the Jachymov silver mines was dying out. On top of the large, forgotten pit-heaps, powdery minerals began to appear, vividly coloured, originating from the decomposition of the pitchblende. These colourful layers, in which zippeite was in the majority, gave Patera the idea of utilizing the uranium minerals in the manufacture of paints. Mining began in 1859 not only for the products which resulted from uraninite's decomposition, but for uraninite itself. A variety of yellow paints were manufactured because among all the secondary minerals on the pit-heap there was a prevalence of the yellow powdery coatings.
Zippeite is one of the so-called 'uranium ochres'. It occurs in association with uranopilite, a monoclinic, complex water-soluble alkaline with othe |
https://en.wikipedia.org/wiki/Rietveld | Rietveld, Dutch for field of reed, can refer to:
People
Gerrit Rietveld (1888–1964), Dutch designer and architect
Hugo Rietveld (1932–2016), Dutch crystallographer who invented the Rietveld refinement method
Kees Rietveld (born 1969), Dutch singer
Pelle Rietveld (born 1985), Dutch decathlete
Piet Rietveld (1952–2013), Dutch economist
Wilhelmina Rietveld (1949–1973), Dutch-Canadian model
Places
Rietveld, Giessenlanden, a hamlet near Arkel, Netherlands
Rietveld, Woerden, a hamlet in the municipality Woerden, Netherlands
Rietveld, Rijnwoude, a hamlet near Hazerswoude, Netherlands
Rietveld, Nord, a hamlet near Wormhout, Nord, France
Other
Rietveld refinement, a technique for use in the characterisation of crystalline materials
Gerrit Rietveld Academie, a Dutch Academy of art and design
Rietveld (software), a code review tool written by Guido van Rossum
Dutch-language surnames |
https://en.wikipedia.org/wiki/Motor%E2%80%93generator | A motor–generator (an M–G set) is a device for converting electrical power to another form. Motor–generator sets are used to convert frequency, voltage, or phase of power. They may also be used to isolate electrical loads from the electrical power supply line. Large motor–generators were widely used to convert industrial amounts of power while smaller motor–generators (such as the one shown in the picture) were used to convert battery power to higher DC voltages.
While a motor–generator set may consist of distinct motor and generator machines coupled together, a single unit dynamotor (for dynamo–motor) has the motor coils and the generator coils wound around a single rotor; both the motor and generator therefore share the same outer field coils or magnets. Typically the motor coils are driven from a commutator on one end of the shaft, while the generator coils provide output to another commutator on the other end of the shaft. The entire rotor and shaft assembly is smaller, lighter, and cheaper than a pair of machines, and does not require exposed drive shafts.
Low-powered consumer devices such as vacuum tube vehicle radio receivers did not use expensive, noisy and bulky motor–generators. Instead, they used an inverter circuit consisting of a vibrator (a self-exciting relay) and a transformer to produce the higher voltages required for the vacuum tubes from the vehicle's 6 or 12 V battery.
Electrical power handling
In the context of electric power generation and large fix |
https://en.wikipedia.org/wiki/Soil%20classification | Soil classification deals with the systematic categorization of soils based on distinguishing characteristics as well as criteria that dictate choices in use.
Overview
Soil classification is a dynamic subject, from the structure of the system, to the definitions of classes, to the application in the field. Soil classification can be approached from the perspective of soil as a material and soil as a resource.
Inscriptions at the temple of Horus at Edfu outline a soil classification used by Tanen to determine what kind of temple to build at which site. Ancient Greek scholars produced a number of classification based on several different qualities of the soil.
Engineering
Geotechnical engineers classify soils according to their engineering properties as they relate to use for foundation support or building material. Modern engineering classification systems are designed to allow an easy transition from field observations to basic predictions of soil engineering properties and behaviors.
The most common engineering classification system for soils in North America is the Unified Soil Classification System (USCS). The USCS has three major classification groups: (1) coarse-grained soils (e.g. sands and gravels); (2) fine-grained soils (e.g. silts and clays); and (3) highly organic soils (referred to as "peat"). The USCS further subdivides the three major soil classes for clarification. It distinguishes sands from gravels by grain size, classifying some as "well-graded" and t |
https://en.wikipedia.org/wiki/Serb%20People%27s%20Party%20%28Montenegro%29 | The Serb People's Party ( / Srpska narodna stranka, SNS) was a political party in Montenegro.
The SNS was led by Andrija Mandić. At the last legislative elections in Montenegro, on September 10, 2006, the Serb List, led by the SNS, won 12 out of 81 seats. It was then the largest political group in the Parliament of Montenegro right after the ruling Democratic Party of Socialists-Social Democratic Party coalition.
In January 2009, it merged with to People's Socialist Party of Montenegro (NSS) to form the New Serb Democracy.
Overview
The SNS was an ethnic Serb party that promoted the rights of the Serb ethnic group against what it sees as state-sponsored discrimination. Unlike the pro-federalist Socialist People's Party of Montenegro (SNP) which is left-oriented (being social-democratic), the SNS is focused primarily on representing the interests of Serb people in Montenegro around a center-right cultural conservative program. It presented itself as one of the successors to the old People's Party in the founded in 1906 in the Kingdom of Montenegro, alongside the current People's Party of Montenegro.
Its platform consisted of protection of the ethnic Serb community in the smaller republic against what it sees as the apartheid-like policies of the government of Milo Đukanović whom it has vehemently opposed since its creation. The SNS also supported a restoration of tighter relations between Serbia and Montenegro in conjunction with Euro-Atlantic integration.
In 1997 the Peop |
https://en.wikipedia.org/wiki/D%C3%BCrrr%C3%B6hrsdorf-Dittersbach | Dürrröhrsdorf-Dittersbach () is a municipality in the district of Sächsische Schweiz-Osterzgebirge, Saxony, Germany. It is located on the river Wesenitz, 6 km west of Stolpen, 9 km northeast of Pirna and 18 km east of Dresden.
Subdivisions
Dittersbach
Dobra
Dürrröhrsdorf
Elbersdorf
Porschendorf
Stürza
Wilschdorf
Wünschendorf
Main sights
The Belvedere on the Schöne Höhe hill, a tower decorated with frescoes by painter Carl Gottlieb Peschel after works of Johann Wolfgang Goethe. Founded by Johann Gottlob von Quandt (1787–1859), it includes a local history exhibition.
Dittersbacher Jahrmarkt
References
External links
Schöne Höhe
Quandt-Verein
SV-Wesenitztal e.V. |
https://en.wikipedia.org/wiki/Logarithmic%20distribution | In probability and statistics, the logarithmic distribution (also known as the logarithmic series distribution or the log-series distribution) is a discrete probability distribution derived from the Maclaurin series expansion
From this we obtain the identity
This leads directly to the probability mass function of a Log(p)-distributed random variable:
for k ≥ 1, and where 0 < p < 1. Because of the identity above, the distribution is properly normalized.
The cumulative distribution function is
where B is the incomplete beta function.
A Poisson compounded with Log(p)-distributed random variables has a negative binomial distribution. In other words, if N is a random variable with a Poisson distribution, and Xi, i = 1, 2, 3, ... is an infinite sequence of independent identically distributed random variables each having a Log(p) distribution, then
has a negative binomial distribution. In this way, the negative binomial distribution is seen to be a compound Poisson distribution.
R. A. Fisher described the logarithmic distribution in a paper that used it to model relative species abundance.
See also
Poisson distribution (also derived from a Maclaurin series)
References
Further reading
Discrete distributions
Logarithms |
https://en.wikipedia.org/wiki/Yule%E2%80%93Simon%20distribution | In probability and statistics, the Yule–Simon distribution is a discrete probability distribution named after Udny Yule and Herbert A. Simon. Simon originally called it the Yule distribution.
The probability mass function (pmf) of the Yule–Simon (ρ) distribution is
for integer and real , where is the beta function. Equivalently the pmf can be written in terms of the rising factorial as
where is the gamma function. Thus, if is an integer,
The parameter can be estimated using a fixed point algorithm.
The probability mass function f has the property that for sufficiently large k we have
This means that the tail of the Yule–Simon distribution is a realization of Zipf's law: can be used to model, for example, the relative frequency of the th most frequent word in a large collection of text, which according to Zipf's law is inversely proportional to a (typically small) power of .
Occurrence
The Yule–Simon distribution arose originally as the limiting distribution of a particular model studied by Udny Yule in 1925 to analyze the growth in the number of species per genus in some higher taxa of biotic organisms. The Yule model makes use of two related Yule processes, where a Yule process is defined as a continuous time birth process which starts with one or more individuals. Yule proved that when time goes to infinity, the limit distribution of the number of species in a genus selected uniformly at random has a specific form and exhibits a power-law behavior in its t |
https://en.wikipedia.org/wiki/Vocal%20sac | The vocal sac is the flexible membrane of skin possessed by most male frogs and toads. The purpose of the vocal sac is usually as an amplification of their mating or advertisement call. The presence or development of the vocal sac is one way of externally determining the sex of a frog or toad in many species; taking frogs as an example;
The vocal sac is open to the mouth cavity of the frog, with two slits on either side of the tongue. To call, the frog inflates its lungs and shuts its nose and mouth. Air is then expelled from the lungs, through the larynx, and into the vocal sac. The vibrations of the larynx emits a sound, which resonates on the elastic membrane of the vocal sac. The resonance causes the sound to be amplified and allows the call to carry further. Muscles within the body wall force the air back and forth between the lungs and vocal sac.
Development
The development of the vocal sac is different in most species, however they mostly follow the same process. The development of the unilobular vocal sac begins with two small growths on the floor of the mouth. These grow until they form two small pouches, which expand until they meet in the centre of the mouth and form one large cavity, which then grows until it is fully developed.
Purpose
The primary purpose of the vocal sac is to amplify the advertisement call of the male, and attract females from as large an area as possible. Species of frog without vocal sacs may only be heard within a radius of a few metres, |
https://en.wikipedia.org/wiki/Interleukin%202 | Interleukin-2 (IL-2) is an interleukin, a type of cytokine signaling molecule in the immune system. It is a 15.5–16 kDa protein that regulates the activities of white blood cells (leukocytes, often lymphocytes) that are responsible for immunity. IL-2 is part of the body's natural response to microbial infection, and in discriminating between foreign ("non-self") and "self". IL-2 mediates its effects by binding to IL-2 receptors, which are expressed by lymphocytes. The major sources of IL-2 are activated CD4+ T cells and activated CD8+ T cells. Put shortly the function of IL-2 is to stimulate the growth of helper, cytotoxic and regulatory T cells.
IL-2 receptor
IL-2 is a member of a cytokine family, each member of which has a four alpha helix bundle; the family also includes IL-4, IL-7, IL-9, IL-15 and IL-21. IL-2 signals through the IL-2 receptor, a complex consisting of three chains, termed alpha (CD25), beta (CD122) and gamma (CD132). The gamma chain is shared by all family members.
The IL-2 receptor (IL-2R) α subunit binds IL-2 with low affinity (Kd~ 10−8 M). Interaction of IL-2 and CD25 alone does not lead to signal transduction due to its short intracellular chain but has the ability (when bound to the β and γ subunit) to increase the IL-2R affinity 100-fold. Heterodimerization of the β and γ subunits of IL-2R is essential for signalling in T cells. IL-2 can signalize either via intermediate-affinity dimeric CD122/CD132 IL-2R (Kd~ 10−9 M) or high-affinity trimeric C |
https://en.wikipedia.org/wiki/Barbarea%20verna | Barbarea verna is a biennial herb in the family Brassicaceae. Common names include land cress, American cress, bank cress, black wood cress, Belle Isle cress, Bermuda cress, poor man's cabbage, early yellowrocket, early wintercress, scurvy cress, creasy greens, and upland cress. It is native to southern Europe and western Asia, and naturalized elsewhere It has been cultivated as a leaf vegetable in England since the 17th century. As it requires less water than watercress, it is easier to cultivate.
Description
Annual or biennial, winter green, herbaceous plant in the Brassicaceae. The seeds typically germinate in the autumn to form an over-wintering rosette. The following spring, it grows a main stem up to about 90 cm, sometimes up to 130 cm, which is pale green, groovy (sulcate) and occasionally branched. The leaves are alternate and pinnate with clasping auricles at the base and between 4 and 11 pairs of sub-opposite lobes. The upper leaves have much narrower lobes than those found lower down. The whole plant is almost entirely glabrous.
The flowers appear in early spring. The inflorescence is a terminal raceme, or lateral raceme arising from the leaf axils, with 6 to 25 flowers on short 3-8mm pedicels. There are four yellowy green sepals, 5mm long and four bright yellow petals each 8mm long. Six stamens and one style with a capitate stigma at the tip.
Uses
Land cress is considered a satisfactory substitute for watercress. It can be used in sandwiches, or salads, or coo |
https://en.wikipedia.org/wiki/Cyanotrichite | Cyanotrichite is a hydrous copper aluminium sulfate mineral with formula Cu4Al2[(OH)12|SO4]·2H2O, also known as lettsomite. Cyanotrichite forms velvety radial acicular crystal aggregates of extremely fine fibers. It crystallizes in the monoclinic system and forms translucent bright blue acicular crystal clusters or drusey coatings. The Mohs hardness is 2 and the specific gravity ranges from 2.74 to 2.95. Refractive indices are nα=1.588 nβ=1.617 nγ=1.655.
Occurrence and discovery
It is an oxidation product of primary copper mineralization in a weathering environment with abundant aluminium and sulfate. Associated minerals include brochantite, spangolite, chalcophyllite, olivenite, tyrolite, parnauite, azurite and malachite.
The main deposits are Cap la Garrone in the Var (France), Romania and Arizona (US).
It was first described in 1839 from Moldova Nouă, Banat, Romania. The name is from Greek kyaneos for "blue" and triches for "hair" referring to the typical color and habit. Its earlier name, Lettsomite, is taken from the name of William Garrow Lettsom (1804–1887), co-author of the 1858 Manual of the Mineralogy of Great Britain and Ireland.
References
Palache, C., H. Berman, and C. Frondel (1951) Dana’s System of Mineralogy, (7th edition), v. II, p. 578–579. PDF file
Mineral galleries
Copper(II) minerals
Aluminium minerals
Sulfate minerals
Monoclinic minerals
Minerals in space group 12 |
https://en.wikipedia.org/wiki/Valentinite | Valentinite is an antimony oxide mineral with formula Sb2O3. Valentinite crystallizes in the orthorhombic system and typically forms as radiating clusters of euhedral crystals or as fibrous masses. It is colorless to white with occasional shades or tints of yellow and red. It has a Mohs hardness of 2.5 to 3 and a specific gravity of 5.76. Valentinite occurs as a weathering product of stibnite and other antimony minerals. It is dimorphous with the isometric antimony oxide senarmontite.
Historical data
Valentinite is a mineral named in the middle of the 19th century in honour of Basilius Valentinus, a writer on alchemy. He is the supposed author of the first book to give a detailed description of antimony and its compounds. From the contents of the book it is also obvious that Valentinus was familiar with the synthetic preparation of antimony trioxide, which was called 'the antimony flower'.
Valentinite was first described in 1845 for an occurrence in the Les Chalanches Mine, Allemond, Isère, Auvergne-Rhône-Alpes, France. The first description of its occurrence in the region of Příbram in Bohemia comes roughly from the same time. This particular locality at one time produced the very best crystals of this mineral. The largest crystals found there measured up to 3 cm. Grouped in rich druses, they developed in vein cavities with galena.
Occurrence
Valentinite is a weathering product of hydrothermal antimony-bearing veins, where it forms as a secondary mineral through oxidati |
https://en.wikipedia.org/wiki/Ch%C3%A2teau%20Latour | Château Latour is a French wine estate, rated as a First Growth under the 1855 Bordeaux Classification. Latour lies at the very southeastern tip of the commune of Pauillac in the Médoc region to the north-west of Bordeaux, at its border with Saint-Julien, and only a few hundred metres from the banks of the Gironde estuary.
The estate produces three red wines in all. In addition to its Grand vin (LWIN 1012316), Latour has also produced the second wine Les Forts de Latour (LWIN 1010309) since 1966, and a third wine, simply named Pauillac (LWIN 1013821), has been released every year since 1989. An impériale (six-litre bottle) of 1961 Château Latour sold for £135,000 in 2011.
History
The site has been occupied since at least 1331 when Tor à Saint-Lambert was built by Gaucelme de Castillon, and the estate dating to at least 1378. A garrison fort was built 300 metres from the estuary to guard against attack during the Hundred Years' War. The tower, the name mutating with time to La Tour en Saint-Mambert and Saint-Maubert, gave its name to the estate around the fortress and was in English hands until the Battle of Castillon in 1453, and its complete destruction by the forces of the King of France. The original tower no longer exists, but in the 1620s a circular tower (La Tour de Saint-Lambert) was built on the estate named after Simon Ledwidge and though it is actually designed as a pigeon roost, it remains a strong symbol of the vineyard. Though two centuries apart, this buildi |
https://en.wikipedia.org/wiki/Shackleton%20Inlet | The Shackleton Inlet is a reentrant, about 16 km (10 mi) wide, between Cape Wilson and Cape Lyttelton. It is occupied by the terminus of the Nimrod Glacier descending at a low gradient from the bordering highlands to the Ross Ice Shelf.
Discovered by Capt. Robert Falcon Scott, in December 1902, while on his attempted trip to the South Pole. He was accompanied on this trip by Dr. Edward A. Wilson and Lt. (later Sir) Ernest Shackleton, for whom this inlet was named.
External links
Inlets of Antarctica
Bodies of water of the Ross Dependency
Shackleton Coast |
https://en.wikipedia.org/wiki/Eosinophilic | Eosinophilic (Greek suffix -phil-, meaning loves eosin) is the staining of tissues, cells, or organelles after they have been washed with eosin, a dye.
Eosin is an acidic dye for staining cell cytoplasm, collagen, and muscle fibers. Eosinophilic describes the appearance of cells and structures seen in histological sections that take up the staining dye eosin. Such eosinophilic structures are, in general, composed of protein.
Eosin is usually combined with a stain called hematoxylin to produce a hematoxylin- and eosin-stained section (also called an H&E stain, HE or H+E section). It is the most widely used histological stain for a medical diagnosis. When a pathologist examines a biopsy of a suspected cancer, they will stain the biopsy with H&E.
Some structures seen inside cells are described as being eosinophilic; for example, Lewy and Mallory bodies.
Some cells are also described as eosinophilic, such as Leukocytes.
See also
Basophilic (affinity to hematoxylin)
Eosinophil
Eosinophilia
Eosinophilic meningitis
Acidophile (histology)
References
Anatomical pathology
Histology |
https://en.wikipedia.org/wiki/Piston%20valve | A piston valve is a device used to control the motion of a fluid along a tube or pipe by means of the linear motion of a piston within a chamber or cylinder.
Examples of piston valves are:
The valves used in many brass instruments
The valves used in pneumatic cannons
The valves used in many stationary steam engines and steam locomotives
Brass instruments
Cylindrical piston valves called Périnet valves (after their inventor François Périnet) are used to change the length of tube in the playing of most brass instruments, particularly the trumpet-like members of the family (cornet, flugelhorn, saxhorn, etc.).
Other brass instruments use rotary valves, notably the orchestral horns and many tuba models, but also a number of rotary-valved variants of those brass instruments which more commonly employ piston valves.
The first piston-valved musical instruments were developed just after the start of the 19th century. The Stölzel valve (invented by Heinrich Stölzel in 1814) was an early variety. In the mid 19th century the Vienna valve was an improved design. However most professional musicians preferred rotary valves for quicker, more reliable action, until better designs of piston valves were mass manufactured towards the end of the 19th century.
Pneumatic cannon
A piston valve can also refer to a 2-way 2-position, pilot-operated spool valve. The term is extremely popular among spud gun enthusiasts who often build homemade piston valves for use in pneumatic cannon. Valves a |
https://en.wikipedia.org/wiki/1957%20French%20Grand%20Prix | The 1957 French Grand Prix was a Formula One motor race held on 7 July 1957 at Rouen-Les-Essarts. It was race 4 of 8 in the 1957 World Championship of Drivers.
Classification
Qualifying
Race
Notes
– Includes 1 point for fastest lap
Debuts
This was the first Formula One race for Herbert MacKay-Fraser and Mike MacDowel.
Shared drive
Car #24: Mike MacDowel (30 laps) and Jack Brabham (38 laps).
Championship standings after the race
Drivers' Championship standings
Note: Only the top five positions are included.
References
French Grand Prix
French Grand Prix
1957 in French motorsport |
https://en.wikipedia.org/wiki/1957%20Italian%20Grand%20Prix | The 1957 Italian Grand Prix was a Formula One motor race held on 8 September 1957 at Monza. It was the eighth and final race in the 1957 World Championship of Drivers.
Classification
Qualifying
Race
Notes
– 1 point for fastest lap
Shared drives
Car #8: Giorgio Scarlatti (50 laps) and Harry Schell (34 laps). They shared the 2 points for fifth place.
Car #28: André Simon (40 laps) and Ottorino Volonterio (32 laps).
Championship standings after the race
Drivers' Championship standings
Note: Only the top five positions are included. Only the best 5 results counted towards the Championship. Numbers without parentheses are Championship points; numbers in parentheses are total points scored.
References
Italian Grand Prix
Italian Grand Prix
Grand Prix |
https://en.wikipedia.org/wiki/Spermatocele | Spermatocele is a fluid-filled cyst that develops in the epididymis. The fluid is usually a clear or milky white color and may contain sperm. Spermatoceles are typically filled with spermatozoa and they can vary in size from several millimeters to many centimeters. Small spermatoceles are relatively common, occurring in an estimated 30 percent of males. They are generally not painful. However, some people may experience discomfort such as a dull pain in the scrotum from larger spermatoceles. They are not cancerous, nor do they cause an increased risk of testicular cancer. Additionally, unlike varicoceles, they do not reduce fertility.
History
"Spermatocele" is originally derived from the Greek term spermatos (sperm) and kele (cavity or mass). Oftentimes, "epididymal cyst" has been used interchangeably with "spermatocele." However, it is important to note their differences. Epididymal cysts may appear anywhere along or within the epididymis and do not contain sperm, whereas spermatoceles may contain sperm. Epididymal cysts have been shown to occur more frequently in children before reaching puberty.
Epidemiology
Spermatoceles usually affect men who are middle-aged and can, although rarely, affect children during puberty. The incidence rate is around 5-20% for children. It is estimated that approximately 30 percent of men have been diagnosed with small spermatoceles while less have larger spermatoceles. The incidence of spermatoceles increases as men age. Before puberty, ch |
https://en.wikipedia.org/wiki/1977%20Brazilian%20Grand%20Prix | The 1977 Brazilian Grand Prix was a Formula One motor race held at Interlagos on 23 January 1977.
Qualifying
Qualifying classification
Race
Report
James Hunt took pole again with Carlos Reutemann second and Mario Andretti third on the grid. Home hero Carlos Pace took the lead at the start, with Hunt dropping behind Reutemann as well but soon Hunt was back behind Pace and attacking. There was contact, and Hunt took the lead whereas Pace had to pit for repairs. Hunt led Reutemann until he began to suffer from tyre troubles and was passed by Reutemann. Hunt pitted for new tyres, and rejoined fourth and soon passed Niki Lauda in the Ferrari and John Watson to reclaim second. Reutemann marched on to victory, Hunt was second and Lauda third after Watson crashed out.
Classification
Championship standings after the race
Drivers' Championship standings
Constructors' Championship standings
Note: Only the top five positions are included for both sets of standings.
References
Brazilian Grand Prix
Brazilian Grand Prix
Grand Prix
Brazilian Grand Prix |
https://en.wikipedia.org/wiki/Resonance%20%28disambiguation%29 | Resonance is the tendency of a physical system to oscillate at great amplitude at certain frequencies.
Resonance may also refer to:
Science
Acoustic resonance, resonance of sound waves
Electrical resonance, resonance of electrical potential or current
Fano resonance
Feshbach resonance
Limbic resonance
Magnetic resonance
Mechanical resonance, resonance of physical motion
Nuclear magnetic resonance (NMR)
Orbital resonance, in celestial mechanics
Planetary wave resonance, a mechanism hypothesised to explain extreme weather events
Resonance (chemistry), the electronic delocalization in molecules often represented via a combination of related Lewis structures
Resonance fluorescence
Resonances in scattering from potentials
Resonance (journal), an Indian journal of education
Resonance (particle physics), of an isolated particle capable of decay that decays spontaneously
Shape resonance
Sympathetic resonance
Music
Resonance FM, a London-based community radio station run by the London Musicians Collective
Resonance, the magazine of the London Musicians Collective
Resonance, the magazine for players of the resophonic guitar
Pierre Bachelet (1944–2005), artist known for the 1973 hit "O.K. Chicago"
Resonance, composition by Liviu Marinescu
Resonance, a program presented by the Adelaide Guitar Festival
Albums
Resonance (Anathema album), a 2001 compilation album by British rock band Anathema
Resonance Vol. 2, 2002
Resonance (Antigama album), 2007
Resonance ( |
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