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https://en.wikipedia.org/wiki/Betavoltaic%20device
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A betavoltaic device (betavoltaic cell or betavoltaic battery) is a type of nuclear battery which generates electric current from beta particles (electrons) emitted from a radioactive source, using semiconductor junctions. A common source used is the hydrogen isotope tritium.
Unlike most nuclear power sources which use nuclear radiation to generate heat which then is used to generate electricity, betavoltaic devices use a non-thermal conversion process, converting the electron-hole pairs produced by the ionization trail of beta particles traversing a semiconductor.
Betavoltaic power sources (and the related technology of alphavoltaic power sources) are particularly well-suited to low-power electrical applications where long life of the energy source is needed, such as implantable medical devices or military and space applications.
History
Betavoltaics were invented in the 1970s. Some pacemakers in the 1970s used betavoltaics based on promethium, but were phased out as cheaper lithium batteries were developed.
Early semiconducting materials weren't efficient at converting electrons from beta decay into usable current, so higher energy, more expensive—and potentially hazardous—isotopes were used. The more efficient semiconducting materials used can be paired with relatively benign isotopes such as tritium, which produce less radiation.
The Betacel was considered the first successfully commercialized betavoltaic battery.
Proposals
The primary use for betavoltaics is for
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https://en.wikipedia.org/wiki/Interactive%20Multimedia%20Association
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The Interactive Multimedia Association (IMA) was an industry association which developed a set of audio algorithms. The most important is the ADPCM algorithm which is in use by Apple and Microsoft.
The Interactive Multimedia Association ceased operations around 1998. An archived copy of the document IMA Recommended Practices for Enhancing Digital Audio Compatibility in Multimedia Systems (version 3.0), which describes the IMA ADPCM algorithm, is available.
External links
RFC 3551, page 13 - IMA ADPCM (DVI4)
References
Standards organizations in the United States
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https://en.wikipedia.org/wiki/Rijndael%20S-box
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The Rijndael S-box is a substitution box (lookup table) used in the Rijndael cipher, on which the Advanced Encryption Standard (AES) cryptographic algorithm is based.
Forward S-box
The S-box maps an 8-bit input, , to an 8-bit output, . Both the input and output are interpreted as polynomials over GF(2). First, the input is mapped to its multiplicative inverse in , Rijndael's finite field. Zero, as the identity, is mapped to itself. This transformation is known as the Nyberg S-box after its inventor Kaisa Nyberg. The multiplicative inverse is then transformed using the following affine transformation:
where is the S-box output and is the multiplicative inverse as a vector.
This affine transformation is the sum of multiple rotations of the byte as a vector, where addition is the XOR operation:
where represents the multiplicative inverse, is the bitwise XOR operator, is a left bitwise circular shift, and the constant is given in hexadecimal.
An equivalent formulation of the affine transformation is
where , , and are 8 bit arrays, is 01100011, and subscripts indicate a reference to the indexed bit.
Another equivalent is:
where is polynomial multiplication of and taken as bit arrays.
Inverse S-box
The inverse S-box is simply the S-box run in reverse. For example, the inverse S-box of b8 is 9a. It is calculated by first calculating the inverse affine transformation of the input value, followed by the multiplicative inverse. The inverse affine transforma
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https://en.wikipedia.org/wiki/Burst%20noise
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Burst noise is a type of electronic noise that occurs in semiconductors and ultra-thin gate oxide films. It is also called random telegraph noise (RTN), popcorn noise, impulse noise, bi-stable noise, or random telegraph signal (RTS) noise.
It consists of sudden step-like transitions between two or more discrete voltage or current levels, as high as several hundred microvolts, at random and unpredictable times. Each shift in offset voltage or current often lasts from several milliseconds to seconds, and sounds like popcorn popping if hooked up to an audio speaker.
Burst noise was first observed in early point contact diodes, then re-discovered during the commercialization of one of the first semiconductor op-amps; the 709. No single source of burst noise is theorized to explain all occurrences, however the most commonly invoked cause is the random trapping and release of charge carriers at thin film interfaces or at defect sites in bulk semiconductor crystal. In cases where these charges have a significant impact on transistor performance (such as under a MOS gate or in a bipolar base region), the output signal can be substantial. These defects can be caused by manufacturing processes, such as heavy ion implantation, or by unintentional side-effects such as surface contamination.
Individual op-amps can be screened for burst noise with peak detector circuits, to minimize the amount of noise in a specific application.
Burst noise is modeled mathematically by means of the
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https://en.wikipedia.org/wiki/Magnetosonic%20wave
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In physics, magnetosonic waves, also known as magnetoacoustic waves, are low-frequency compressive waves driven by mutual interaction between an electrically conducting fluid and a magnetic field. They are associated with compression and rarefaction of both the fluid and the magnetic field, as well as with an effective tension that acts to straighten bent magnetic field lines. The properties of magnetosonic waves are highly dependent on the angle between the wavevector and the equilibrium magnetic field and on the relative importance of fluid and magnetic processes in the medium. They only propagate with frequencies much smaller than the ion cyclotron or ion plasma frequencies of the medium, and they are nondispersive at small amplitudes.
There are two types of magnetosonic waves, fast magnetosonic waves and slow magnetosonic waves, which—together with Alfvén waves—are the normal modes of ideal magnetohydrodynamics. The fast and slow modes are distinguished by magnetic and gas pressure oscillations that are either in-phase or anti-phase, respectively. This results in the phase velocity of any given fast mode always being greater than or equal to that of any slow mode in the same medium, among other differences.
Magnetosonic waves have been observed in the Sun's corona and provide an observational foundation for coronal seismology.
Characteristics
Magnetosonic waves are a type of low-frequency wave present in electrically conducting, magnetized fluids, such as plasmas and
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https://en.wikipedia.org/wiki/Transformation%20%28function%29
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In mathematics, a transformation is a function f, usually with some geometrical underpinning, that maps a set X to itself, i.e. .
Examples include linear transformations of vector spaces and geometric transformations, which include projective transformations, affine transformations, and specific affine transformations, such as rotations, reflections and translations.
Partial transformations
While it is common to use the term transformation for any function of a set into itself (especially in terms like "transformation semigroup" and similar), there exists an alternative form of terminological convention in which the term "transformation" is reserved only for bijections. When such a narrow notion of transformation is generalized to partial functions, then a partial transformation is a function f: A → B, where both A and B are subsets of some set X.
Algebraic structures
The set of all transformations on a given base set, together with function composition, forms a regular semigroup.
Combinatorics
For a finite set of cardinality n, there are nn transformations and (n+1)n partial transformations.
See also
Coordinate transformation
Data transformation (statistics)
Geometric transformation
Infinitesimal transformation
Linear transformation
Rigid transformation
Transformation geometry
Transformation semigroup
Transformation group
Transformation matrix
References
External links
Functions and mappings
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https://en.wikipedia.org/wiki/British%20Rail%20Class%20144
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The British Rail Class 144 Pacer was a diesel multiple unit (DMU) passenger train built at Derby between 1986 and 1987. BR, seeking to procure improved derivatives of the earlier Class 141, placed an order with the manufacturers British Rail Engineering Limited (BREL) and Walter Alexander to construct their own variant, the Class 144. A total of 23 units were constructed. All units have now retired from mainline service, though the majority of the units have been acquired for preservation on heritage railways and in other uses. As of December 2022, 19 out of the 23 units have been purchased following withdrawal for this purpose, of which 14 units are in operational condition.
Background
By the beginning of the 1980s, British Rail (BR) operated a large fleet of first generation DMUs, which had been constructed in prior decades to various designs. While formulating its long-term strategy for this sector of its operations, British Rail planners recognised that there would be considerable costs incurred by undertaking refurbishment programmes necessary for the continued use of these aging multiple units, particularly due to the necessity of handling and removing hazardous materials such as asbestos. In light of the high costs involved in retention, planners examined the prospects for the development and introduction of a new generation of DMUs to succeed the first generation.
In the concept stage, two separate approaches were devised, one involving a so-called railbus that pr
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https://en.wikipedia.org/wiki/BRENDA
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BRENDA (The Comprehensive Enzyme Information System) is an information system representing one of the most comprehensive enzyme repositories. It is an electronic resource that comprises molecular and biochemical information on enzymes that have been classified by the IUBMB. Every classified enzyme is characterized with respect to its catalyzed biochemical reaction. Kinetic properties of the corresponding reactants (that is, substrates and products) are described in detail. BRENDA contains enzyme-specific data manually extracted from primary scientific literature and additional data derived from automatic information retrieval methods such as text mining. It provides a web-based user interface that allows a convenient and sophisticated access to the data.
History
BRENDA was founded in 1987 at the former German Research Centre for Biotechnology (now the Helmholtz Centre for Infection Research) in Braunschweig and was originally published as a series of books. Its name was originally an acronym for the BRaunschweig ENzyme DAtabase. From 1996 to 2007, BRENDA was located at the University of Cologne. There, BRENDA developed into a publicly accessible enzyme information system. In 2007, BRENDA returned to Braunschweig. Currently, BRENDA is maintained and further developed at the BRICS ( Braunschweig Integrated Centre of Systems Biology) at the TU Braunschweig.
In 2018 BRENDA was appointed to ELIXIR Core Data Resource with fundamental importance to biological and biomedical resea
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https://en.wikipedia.org/wiki/Bannock%20people
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The Bannock tribe were originally Northern Paiute but are more culturally affiliated with the Northern Shoshone. They are in the Great Basin classification of Indigenous People. Their traditional lands include northern Nevada, southeastern Oregon, southern Idaho, and western Wyoming. Today they are enrolled in the federally recognized Shoshone-Bannock Tribes of the Fort Hall Reservation of Idaho, located on the Fort Hall Indian Reservation.
History
The Northern Paiute have a history of trade with surrounding tribes. In the 1700s, the bands in eastern Oregon traded with the tribes to the north, who by 1730 had acquired the horse. In the mid-18th century, some bands developed a horse culture and split off to become the Bannock tribe. The horse gave the tribe a greater range, from Oregon to northern Nevada, southern Idaho, and western Wyoming. They forayed from there on the Bannock Trail to Montana and Canada to hunt buffalo.
The Bannock have traditionally made pottery, utensils from bighorn sheep horns, and carrying bags from salmon skin. Their petroglyphs date back before European contact, and, after the introduction of glass beads, they transferred their geometric design to beadwork. For water transport, they have made tule reed rafts. Prior to the late 19th century, Bannock people fished for salmon on the Snake River in Idaho and in the fall, they hunted buffalo herds. Buffalo hides have provided material for tipis.
The Bannock are prominent in American history due to
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https://en.wikipedia.org/wiki/Schr%C3%B6dinger%E2%80%93Newton%20equation
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The Schrödinger–Newton equation, sometimes referred to as the Newton–Schrödinger or Schrödinger–Poisson equation, is a nonlinear modification of the Schrödinger equation with a Newtonian gravitational potential, where the gravitational potential emerges from the treatment of the wave function as a mass density, including a term that represents interaction of a particle with its own gravitational field. The inclusion of a self-interaction term represents a fundamental alteration of quantum mechanics. It can be written either as a single integro-differential equation or as a coupled system of a Schrödinger and a Poisson equation. In the latter case it is also referred to in the plural form.
The Schrödinger–Newton equation was first considered by Ruffini and Bonazzola in connection with self-gravitating boson stars. In this context of classical general relativity it appears as the non-relativistic limit of either the Klein–Gordon equation or the Dirac equation in a curved space-time together with the Einstein field equations.
The equation also describes fuzzy dark matter and approximates classical cold dark matter described by the Vlasov–Poisson equation in the limit that the particle mass is large.
Later on it was proposed as a model to explain the quantum wave function collapse by Lajos Diósi and Roger Penrose, from whom the name "Schrödinger–Newton equation" originates. In this context, matter has quantum properties, while gravity remains classical even at the fundamental
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https://en.wikipedia.org/wiki/Tim%20Mitchison
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Timothy John Mitchison is a cell biologist and systems biologist and Hasib Sabbagh Professor of Systems Biology at Harvard Medical School in the United States. He is known for his discovery, with Marc Kirschner, of dynamic instability in microtubules, for studies of the mechanism of cell division, and for contributions to chemical biology.
Education and early life
Mitchison was educated at Haberdashers' Aske's Boys' School and completed his Bachelor of Arts degree in Biochemistry at the University of Oxford where he was an undergraduate student of Merton College, Oxford, from 1976 to 1979. He moved to the University of California, San Francisco (UCSF) in 1979 for his PhD which was supervised by Marc Kirschner and investigated the dynamic instability of microtubules.
Career and research
Mitchison returned to the UK for postdoctoral research at the National Institute for Medical Research (NIMR) in London. In 1988 he returned to San Francisco where he was appointed assistant professor at UCSF. In 1994 he wrote an opinion piece for the journal Chemistry & Biology titled "Towards a pharmacological genetics" which helped to launch the field of chemical genetics. In 1997 he moved to Harvard University to become co-director of the Institute for Chemistry and Cell Biology at Harvard Medical School, where he pioneered phenotype-based screening, discovering the small molecule monastrol – the first small-molecule inhibitor of mitosis that does not target tubulin. Monastrol was shown
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https://en.wikipedia.org/wiki/NASDAQ%20Biotechnology%20Index
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The NASDAQ Biotechnology Index is a stock market index made up of securities of NASDAQ-listed companies classified according to the Industry Classification Benchmark as either the Biotechnology or the Pharmaceutical industry. A list of the 213 components of the index is published online.
Criteria
In order to remain included within the index, the components must meet the following criteria:
The security U.S. listing must be exclusively on the NASDAQ National Market (unless the security was dually listed on another U.S. market prior to January 1, 2004 and has continuously maintained such listing).
The issuer of the security must be classified according to the Industry Classification Benchmark as either Biotechnology or Pharmaceuticals.
The security may not be issued by an issuer currently in bankruptcy proceedings.
The security must have a market capitalization of at least $200 million.
The security must have an average daily trading volume of at least 100,000 shares.
The issuer of the security may not have entered into a definitive agreement or other arrangement which would likely result in the security no longer being Index.
The issuer of the security may not have annual financial statements with an audit opinion that is currently withdrawn.
The issuer of the security must have "seasoned" on NASDAQ or another recognized market for at least 6 months; in the case of spin-offs, the operating history of the spin-off will be considered.
Investing in the index
This index
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https://en.wikipedia.org/wiki/Software%20rot
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Software rot (bit rot, code rot, software erosion, software decay, or software entropy) is either a slow deterioration of software quality over time or its diminishing responsiveness that will eventually lead to software becoming faulty, unusable, or in need of upgrade. This is not a physical phenomenon; the software does not actually decay, but rather suffers from a lack of being responsive and updated with respect to the changing environment in which it resides.
The Jargon File, a compendium of hacker lore, defines "bit rot" as a jocular explanation for the degradation of a software program over time even if "nothing has changed"; the idea behind this is almost as if the bits that make up the program were subject to radioactive decay.
Causes
Several factors are responsible for software rot, including changes to the environment in which the software operates, degradation of compatibility between parts of the software itself, and the appearance of bugs in unused or rarely used code.
Environment change
When changes occur in the program's environment, particularly changes which the designer of the program did not anticipate, the software may no longer operate as originally intended. For example, many early computer game designers used the CPU clock speed as a timer in their games. However, newer CPU clocks were faster, so the gameplay speed increased accordingly, making the games less usable over time.
Onceability
There are changes in the environment not related to the pro
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https://en.wikipedia.org/wiki/RecA
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RecA is a 38 kilodalton protein essential for the repair and maintenance of DNA. A RecA structural and functional homolog has been found in every species in which one has been seriously sought and serves as an archetype for this class of homologous DNA repair proteins. The homologous protein is called RAD51 in eukaryotes and RadA in archaea.
RecA has multiple activities, all related to DNA repair. In the bacterial SOS response, it has a co-protease function in the autocatalytic cleavage of the LexA repressor and the λ repressor.
RecA's association with DNA repair is based on its central role in homologous recombination. The RecA protein binds strongly and in long clusters to ssDNA to form a nucleoprotein filament. The protein has more than one DNA binding site, and thus can hold a single strand and double strand together. This feature makes it possible to catalyze a DNA synapsis reaction between a DNA double helix and a complementary region of single-stranded DNA. The RecA-ssDNA filament searches for sequence similarity along the dsDNA. A disordered DNA loop in RecA, Loop 2, contains the residues responsible for DNA homologous recombination. In some bacteria, RecA posttranslational modification via phosphorylation of a serine residue on Loop 2 can interfere with homologous recombination.
The search process induces stretching of the DNA duplex, which enhances sequence complementarity recognition (a mechanism termed conformational proofreading). The reaction initiates the ex
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https://en.wikipedia.org/wiki/Dispersive%20mass%20transfer
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Dispersive mass transfer, in fluid dynamics, is the spreading of mass from highly concentrated areas to less concentrated areas. It is one form of mass transfer.
Dispersive mass flux is analogous to diffusion, and it can also be described using Fick's first law:
where c is mass concentration of the species being dispersed, E is the dispersion coefficient, and x is the position in the direction of the concentration gradient. Dispersion can be differentiated from diffusion in that it is caused by non-ideal flow patterns (i.e. deviations from plug flow) and is a macroscopic phenomenon, whereas diffusion is caused by random molecular motions (i.e. Brownian motion) and is a microscopic phenomenon. Dispersion is often more significant than diffusion in convection-diffusion problems. The dispersion coefficient is frequently modeled as the product of the fluid velocity, U, and some characteristic length scale, α:
Transport phenomena
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https://en.wikipedia.org/wiki/Smith%E2%80%93Lemli%E2%80%93Opitz%20syndrome
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Smith–Lemli–Opitz syndrome is an inborn error of cholesterol synthesis. It is an autosomal recessive, multiple malformation syndrome caused by a mutation in the enzyme 7-Dehydrocholesterol reductase encoded by the DHCR7 gene. It causes a broad spectrum of effects, ranging from mild intellectual disability and behavioural problems to lethal malformations.
Signs and symptoms
SLOS can present itself differently in different cases, depending on the severity of the mutation and other factors. Originally, SLOS patients were classified into two categories (classic and severe) based on physical and mental characteristics, alongside other clinical features. Since the discovery of the specific biochemical defect responsible for SLOS, patients are given a severity score based on their levels of cerebral, ocular, oral, and genital defects. It is then used to classify patients as having mild, classical, or severe SLOS.
Physical characteristics
The most common facial features of SLOS include microcephaly, bitemporal narrowing (reduced distance between temples), ptosis, a short and upturned nose, micrognathia, epicanthal folds, and capillary hemangioma of the nose. Other physical characteristics include:
low-set and posteriorly rotated ears
high-arched, narrow, hard palate
cleft lip/palate
agenesis or hypoplasia of the corpus callosum
cerebellar hypoplasia
increased ventricular size
decreased frontal lobe size
polydactyly of hands or feet
short, proximally placed thumb
other f
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https://en.wikipedia.org/wiki/Einstein%20solid
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The Einstein solid is a model of a crystalline solid that contains a large number of independent three-dimensional quantum harmonic oscillators of the same frequency. The independence assumption is relaxed in the Debye model.
While the model provides qualitative agreement with experimental data, especially for the high-temperature limit, these oscillations are in fact phonons, or collective modes involving many atoms. Albert Einstein was aware that getting the frequency of the actual oscillations would be difficult, but he nevertheless proposed this theory because it was a particularly clear demonstration that quantum mechanics could solve the specific heat problem in classical mechanics.
Historical impact
The original theory proposed by Einstein in 1907 has great historical relevance. The heat capacity of solids as predicted by the empirical Dulong–Petit law was required by classical mechanics, the specific heat of solids should be independent of temperature. But experiments at low temperatures showed that the heat capacity changes, going to zero at absolute zero. As the temperature goes up, the specific heat goes up until it approaches the Dulong and Petit prediction at high temperature.
By employing Planck's quantization assumption, Einstein's theory accounted for the observed experimental trend for the first time. Together with the photoelectric effect, this became one of the most important pieces of evidence for the need of quantization. Einstein used the levels of t
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https://en.wikipedia.org/wiki/Nuclear%20magnetic%20resonance%20spectroscopy
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Nuclear magnetic resonance spectroscopy, most commonly known as NMR spectroscopy or magnetic resonance spectroscopy (MRS), is a spectroscopic technique to observe local magnetic fields around atomic nuclei. This spectroscopy is based on the measurement of absorption of electromagnetic radiations in the radio frequency region from roughly 4 to 900 MHz. Absorption of radio waves in the presence of magnetic field is accompanied by a special type of nuclear transition, and for this reason, such type of spectroscopy is known as Nuclear Magnetic Resonance Spectroscopy. The sample is placed in a magnetic field and the NMR signal is produced by excitation of the nuclei sample with radio waves into nuclear magnetic resonance, which is detected with sensitive radio receivers. The intramolecular magnetic field around an atom in a molecule changes the resonance frequency, thus giving access to details of the electronic structure of a molecule and its individual functional groups.
As the fields are unique or highly characteristic to individual compounds, in modern organic chemistry practice, NMR spectroscopy is the definitive method to identify monomolecular organic compounds.
The principle of NMR usually involves three sequential steps:
The alignment (polarization) of the magnetic nuclear spins in an applied, constant magnetic field B0.
The perturbation of this alignment of the nuclear spins by a weak oscillating magnetic field, usually referred to as a radio-frequency (RF) pulse.
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https://en.wikipedia.org/wiki/CGMP-specific%20phosphodiesterase%20type%205
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Cyclic guanosine monophosphate-specific phosphodiesterase type 5 is an enzyme () from the phosphodiesterase class. It is found in various tissues, most prominently the corpus cavernosum and the retina. It has also been recently discovered to play a vital role in the cardiovascular system.
The phosphodiesterase (PDE) isozymes, found in several tissues including the rod and cone photoreceptor cells of the retina, belong to a large family of cyclic nucleotide PDEs that catalyze cAMP and cGMP hydrolysis.
The interest in PDEs as molecular targets of drug action has grown with the development of isozyme-selective PDE inhibitors that offer potent inhibition of selected isozymes without the side-effects attributed to nonselective inhibitors such as theophylline.
Sildenafil, vardenafil, tadalafil, and avanafil are PDE5 inhibitors that are significantly more potent and selective than zaprinast and other early PDE5 inhibitors.
Action of PDE5
PDE5 is an enzyme that accepts cGMP and breaks it down. Sildenafil, vardenafil and tadalafil are inhibitors of this enzyme, which bind to the catalytic site of PDE5. Both inhibitors bind with high affinity and specificity, and cGMP-binding to the allosteric sites stimulates binding of PDE5 inhibitors at the catalytic site. The kinetics of inhibitor binding and inhibition of catalysis imply the existence of two PDE5 conformers, and results of native gel electrophoresis reveal that PDE5 exists in two apparently distinct conformations, i.e., an ex
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https://en.wikipedia.org/wiki/Nicol%20prism
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A Nicol prism is a type of polarizer. It is an optical device made from calcite crystal used to convert ordinary light into plane polarized light. It is made in such a way that it eliminates one of the rays by total internal reflection, i.e. the ordinary ray is eliminated and only the extraordinary ray is transmitted through the prism.
It was the first type of polarizing prism, invented in 1828 by William Nicol (1770–1851) of Edinburgh.
Mechanism
The Nicol prism consists of a rhombohedral crystal of Iceland spar (a variety of calcite) that has been cut at an angle of 68° with respect to the crystal axis, cut again diagonally, and then rejoined, using a layer of transparent Canada balsam as a glue.
Unpolarized light ray enters through the side face of the crystal, and is split into two orthogonally polarized, differently directed rays by the birefringence property of calcite. The ordinary ray, or o-ray, experiences a refractive index of no = 1.658 in the calcite and undergoes a total internal reflection at the calcite–glue interface because of its angle of incidence at the glue layer (refractive index n = 1.550) exceeds the critical angle for the interface. It passes out the top side of the upper half of the prism with some refraction. The extraordinary ray, or e-ray, experiences a lower refractive index (ne = 1.486) in the calcite crystal and is not totally reflected at the interface because it strikes the interface at a sub-critical angle. The e-ray merely undergoes a s
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https://en.wikipedia.org/wiki/Neurophysin%20I
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Neurophysin I is a carrier protein with a size of 10 KDa and contains 90 to 97 amino acids. It is a cleavage product (formed by splitting of a compound molecule into a simpler one) of preprooxyphysin. It is a neurohypophysial hormone that is transported in vesicles with oxytocin, the other cleavage product, along axons, from magnocellular neurons of the hypothalamus to the posterior lobe of the pituitary. Although it is stored in neurosecretory granules with oxytocin and released with oxytocin, its biological action is unclear.
Function
Neurophysin I is the carrier protein for oxytocin. It is produced in the cell bodies of the paraventricular and supraoptic nuclei and transported to its site of release in the axon terminals of the posterior pituitary. Neurophysin I neurons are more prevalent in the paraventricular nuclei while Neurophysin II neurons are more prevalent in the supraoptic nuclei. Vasopressin, a hormone similar in structure to oxytocin, is analogously bound and transported by Neurophysin II. Both hormones are nine residues long, and share seven of these residues. Oxytocin possesses Ile-3 and Leu-8 whereas vasopressin possesses Phe-3 and Arg-8. Both Ile and Phe are hydrophobic amino acids and undergo analogous binding to neurophysins.
Structure
The amino acid sequence of Neurophysin I is:
NH2 - Ala - Ala - Pro - Asp - Leu - Asp - Val - Arg - Lys - Cys - Leu - Pro - Cys - Gly - Pro - Gly - Gly - Lys - Gly - Arg - Cys - Phe - Gly - Pro - Asn - Ile - Cys - Cys -
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https://en.wikipedia.org/wiki/Crip
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Crip may refer to:
People
Crip Toomey, American football and baseball player and coach
Henry "Crip" Heard (1923–1991), an African-American dancer
Science
CRIP1, the human gene for Cysteine-rich protein 1
CRIP2, the human gene for Cysteine-rich protein 2
Other uses
Chicago, Rock Island and Pacific Railroad, United States
Crip (disability term), reclaimed slang for cripple
Crip theory, a branch of disability studies
CRIP (Clave de Registro e Identidad Personal), a registration and identification code used in Mexico
Crips, a street gang in Los Angeles
Crank Reference index Position (CRiP), an important measurement taken by crankshaft position sensors.
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https://en.wikipedia.org/wiki/Buchi
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Buchi can mean:
Items
Bachi, special Japanese drumsticks
Butsi, the Hispanised term for jin deui (pastry made from glutinous rice) in the Philippines
Büchi automaton, finite state automata extended to infinite inputs
Büchi arithmetic, a mathematical logical fragment
People
Given names
Buchi Atuonwu, Nigerian reggae gospel artist
Buchi (comedian), stage name of Onyebuchi Ojieh, Nigerian comedian
Buchi Emecheta, (d. 2017) Nigerian British writer
Family names
George Büchi (1921–1998), an organic chemist
Julius Richard Büchi (1924–1984), developer of the Büchi automaton
Hernán Büchi (born 1949), Finance Minister of Chile (1985–1989)
Albert Büchi (1907–1988), a Swiss professional road bicycle racer
Nicknames
Yutaka Izubuchi, anime designer and director
Nigerian Igbo first names such as Onyebuchi, Nnabuchi, Maduabuchi, a suffix that translates as "...is God."
Fictional characters
Buchi in One Piece
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https://en.wikipedia.org/wiki/Repressor%20lexA
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Repressor LexA or LexA (Locus for X-ray sensitivity A) is a transcriptional repressor () that represses SOS response genes coding primarily for error-prone DNA polymerases, DNA repair enzymes and cell division inhibitors. LexA forms de facto a two-component regulatory system with RecA, which senses DNA damage at stalled replication forks, forming monofilaments and acquiring an active conformation capable of binding to LexA and causing LexA to cleave itself, in a process called autoproteolysis.
DNA damage can be inflicted by the action of antibiotics, bacteriophages, and UV light. Of potential clinical interest is the induction of the SOS response by antibiotics, such as ciprofloxacin. Bacteria require topoisomerases such as DNA gyrase or topoisomerase IV for DNA replication. Antibiotics such as ciprofloxacin are able to prevent the action of these molecules by attaching themselves to the gyrate–DNA complex, leading to replication fork stall and the induction of the SOS response. The expression of error-prone polymerases under the SOS response increases the basal mutation rate of bacteria. While mutations are often lethal to the cell, they can also enhance survival. In the specific case of topoisomerases, some bacteria have mutated one of their amino acids so that the ciprofloxacin can only create a weak bond to the topoisomerase. This is one of the methods that bacteria use to become resistant to antibiotics. Ciprofloxacin treatment can therefore potentially lead to the gen
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https://en.wikipedia.org/wiki/Marc%20Kirschner
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Marc Wallace Kirschner (born February 28, 1945) is an American cell biologist and biochemist and the founding chair of the Department of Systems Biology at Harvard Medical School. He is known for major discoveries in cell and developmental biology related to the dynamics and function of the cytoskeleton, the regulation of the cell cycle, and the process of signaling in embryos, as well as the evolution of the vertebrate body plan. He is a leader in applying mathematical approaches to biology. He is the John Franklin Enders University Professor at Harvard University. In 2021 he was elected to the American Philosophical Society.
Education and early life
Kirschner was born in Chicago, Illinois, on February 28, 1945. He graduated from Northwestern University with a B.A. in chemistry in 1966. He received a Graduate Research Fellowship from the National Science Foundation in 1966 and earned a doctorate in biochemistry from the University of California, Berkeley in 1971.
Career and research
He held postdoctoral positions at UC Berkeley and at the University of Oxford in England. He became assistant professor at Princeton University in 1972. In 1978 he was made professor at the University of California, San Francisco. In 1993, he moved to Harvard Medical School, where he served as the chair of the new Department of Cell Biology for a decade. He became the founding chair of the HMS Department of Systems Biology in 2003. He was named the John Franklin Enders University Professor in
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https://en.wikipedia.org/wiki/Bernoulli%20differential%20equation
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In mathematics, an ordinary differential equation is called a Bernoulli differential equation if it is of the form
where is a real number. Some authors allow any real , whereas others require that not be 0 or 1. The equation was first discussed in a work of 1695 by Jacob Bernoulli, after whom it is named. The earliest solution, however, was offered by Gottfried Leibniz, who published his result in the same year and whose method is the one still used today.
Bernoulli equations are special because they are nonlinear differential equations with known exact solutions. A notable special case of the Bernoulli equation is the logistic differential equation.
Transformation to a linear differential equation
When , the differential equation is linear. When , it is separable. In these cases, standard techniques for solving equations of those forms can be applied. For and , the substitution reduces any Bernoulli equation to a linear differential equation
For example, in the case , making the substitution in the differential equation produces the equation , which is a linear differential equation.
Solution
Let and
be a solution of the linear differential equation
Then we have that is a solution of
And for every such differential equation, for all we have as solution for .
Example
Consider the Bernoulli equation
(in this case, more specifically a Riccati equation).
The constant function is a solution.
Division by yields
Changing variables gives the equation
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https://en.wikipedia.org/wiki/Pseudo-LRU
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Pseudo-LRU or PLRU is a family of cache algorithms which improve on the performance of the Least Recently Used (LRU) algorithm by replacing values using approximate measures of age rather than maintaining the exact age of every value in the cache.
PLRU usually refers to two cache replacement algorithms: tree-PLRU and bit-PLRU.
Tree-PLRU
Tree-PLRU is an efficient algorithm to select an item that most likely has not been accessed very recently, given a set of items and a sequence of access events to the items.
This technique is used in the CPU cache of the Intel 486 and in many processors in the PowerPC family, such as Freescale's PowerPC G4 used by Apple Computer.
The algorithm works as follows: consider a binary search tree for the items in question. Each node of the tree has a one-bit flag denoting "go left to insert a pseudo-LRU element" or "go right to insert a pseudo-LRU element". To find a pseudo-LRU element, traverse the tree according to the values of the flags. To update the tree with an access to an item N, traverse the tree to find N and, during the traversal, set the node flags to denote the direction that is opposite to the direction taken.
This algorithm can be sub-optimal since it is an approximation. For example, in the above diagram with A, C, B, D cache lines, if the access pattern was: C, B, D, A, on an eviction, B would chosen instead of C. This is because both A and C are in the same half and accessing A directs the algorithm to the other half that d
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https://en.wikipedia.org/wiki/Alvircept%20sudotox
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Alvircept sudotox is a form of recombinant CD4 derived from Pneumonas aeruginosa exotoxin A, or 'PE40, which has a size of 59,187 daltons and is an anti-viral agent.
References
Glycoproteins
Clusters of differentiation
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https://en.wikipedia.org/wiki/Magic%20angle%20spinning
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In solid-state NMR spectroscopy, magic-angle spinning (MAS) is a technique routinely used to produce better resolution NMR spectra. MAS NMR consists in spinning the sample (usually at a frequency of 1 to 130 kHz) at the magic angle θm (ca. 54.74°, where cos2θm=1/3) with respect to the direction of the magnetic field.
Three main interactions responsible in solid state NMR (dipolar, chemical shift anisotropy, quadrupolar) often lead to very broad and featureless NMR lines. However, these three interactions in solids are orientation-dependent and can be averaged to some extent by MAS:
The nuclear dipolar interaction has a dependence, where is the angle between the internuclear axis and the main magnetic field. As a result, the dipolar interaction vanish at the magic angle θm and the interaction contributing to the line broadening is removed. Even though all internuclear vectors cannot be all set to the magic angle, rotating the sample around this axis produces the same effect, provided the frequency is comparable to that of the interaction. In addition, a set of spinning sidebands appear on the spectra, which are sharp lines separated from the isotropic resonance frequency by a multiple of the spinning rate.
The chemical shift anisotropy (CSA) represents the orientation-dependence of the chemical shift. Powder patterns generated by the CSA interaction can be averaged by MAS, resulting to one single resonance centred at the isotropic chemical shift (centre of mass of the p
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https://en.wikipedia.org/wiki/List%20of%20state%20highways%20in%20Idaho
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The Idaho Transportation Department (ITD) is responsible for the establishment and classification of a state highway network, including of roads that are classified as Interstate Highways, U.S. Highways, and state highways within the state of Idaho in the United States. The current state highway marker consists of a white background, black numbering, and a solid black geographic outline of the state of Idaho.
History
During the 1920s, in lieu of numbering its highways, Idaho had a system of lettered Sampson Trails. They were marked by businessman Charles B. Sampson of Boise at no expense to the state, using orange-colored shields. By 1929, the trails system had included of marked highways that covered most of the state. By the mid-1930s, the state had adopted a more standard system of numbered state highways.
In 1978, the ITD began using brown state highway markers to denote scenic Idaho highways, in addition to the main highway markers that featured a black background and white lettering and the name "IDAHO" in black lettering inside a white geographic outline of the state. The brown markers were discontinued around 2012, and in April 2020, ITD changed the coloring of the main state highway marker to its current color scheme, also adding a wide version of the marker for three-digit highways and removing the word "IDAHO" from all markers in the process.
Sampson Trails
The following Sampson Trails were marked:
A, Boise to Wyoming via Twin Falls and Pocatello; became US
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https://en.wikipedia.org/wiki/Neodymium-doped%20yttrium%20orthovanadate
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Neodymium-doped yttrium orthovanadate (Nd:YVO4) is a crystalline material formed by adding neodymium ions to yttrium orthovanadate. It is commonly used as an active laser medium for diode-pumped solid-state lasers. It comes as a transparent blue-tinted material. It is birefringent, therefore rods made of it are usually rectangular.
As in all neodymium-doped laser crystals, the lasing action of Nd:YVO4 is due to its content of neodymium ions, which may be excited by visible or infrared light, and undergo an electronic transition resulting in emission of coherent infrared light at a lower frequency, usually at 1064 nm (other transitions in Nd are available, and can be selected for by external optics).
Basic properties
Atomic density: ~1.37×1020 atoms/cm3
Crystal structure:
zircon tetragonal (tetragonal bipyramidal)
space group D4h
a=b=7.12, c=6.29
Density: 4.22 g/cm3
Mohs hardness: Glass-like, ~5
Thermal expansion coefficient:
αa=4.43×10−6/K
αc=11.37×10−6/K
Thermal conductivity:
parallel to C-axis: 5.23 W·m−1·K−1
perpendicular to C-axis: 5.10 W·m−1·K−1
Optical properties
Lasing wavelengths: 914 nm, 1064 nm, 1342 nm
Crystal class: positive uniaxial, no=na=nb, ne=nc,
no=1.9573, ne=2.1652, at 1064 nm
no=1.9721, ne=2.1858, at 808 nm
no=2.0210, ne=2.2560, at 532 nm
Fluorescence lifetime (spontaneous emission lifetime) as a function of Nd ions concentration:
Absorption cross-section at 808 nm: 5.5×10−20 cm²
Emission cross-section at 1064 nm: 30×10−19 cm² (Reference: JOSA
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https://en.wikipedia.org/wiki/List%20of%20state%20highways%20in%20Vermont
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The following is a list of state highways in Vermont as designated by the Vermont Agency of Transportation (VTrans). The classification of these state highways fall under three primary categories: Interstate Highways, U.S. Highways, and Vermont routes. Routes in Vermont are abbreviated as "VT #" by VTrans and also abbreviated as "VT Route #" and "Route #" in common usage. A small number of minor state highways, typically bypassing old alignments or short connector routes, are instead assigned names and unsigned four-digit numbers beginning with 9. Most state highways are maintained by VTrans; however, portions of some routes and some entire routes are maintained by local governments, such as towns or cities, instead. These town-maintained routes are internally called "state-designated town highways" and are typically designated as "class 1 town highways". Many of Vermont's state-numbered highways retain their numbers from when they were part of the New England road marking system of the 1920s; for instance, VT 9 was part of Route 9 of the New England system.
Prior to 1995, Vermont used the standard circular highway shield to sign all of its routes, which had black numerals on a white circle over a black background. In 1995, Vermont introduced a new shield for state-maintained highways—a green shield with the word "Vermont" at the top. The circular highway shield continues to be used for locally maintained routes. Some state-maintained routes are still signed with the circula
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https://en.wikipedia.org/wiki/Electromagnetic%20tensor
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In electromagnetism, the electromagnetic tensor or electromagnetic field tensor (sometimes called the field strength tensor, Faraday tensor or Maxwell bivector) is a mathematical object that describes the electromagnetic field in spacetime. The field tensor was first used after the four-dimensional tensor formulation of special relativity was introduced by Hermann Minkowski. The tensor allows related physical laws to be written very concisely, and allows for the quantization of the electromagnetic field by Lagrangian formulation described below.
Definition
The electromagnetic tensor, conventionally labelled F, is defined as the exterior derivative of the electromagnetic four-potential, A, a differential 1-form:
Therefore, F is a differential 2-form—that is, an antisymmetric rank-2 tensor field—on Minkowski space. In component form,
where is the four-gradient and is the four-potential.
SI units for Maxwell's equations and the particle physicist's sign convention for the signature of Minkowski space , will be used throughout this article.
Relationship with the classical fields
The Faraday differential 2-form is given by
This is the exterior derivative of its 1-form antiderivative
,
where has ( is a scalar potential for the irrotational/conservative vector field ) and has ( is a vector potential for the solenoidal vector field ).
Note that
where is the exterior derivative, is the Hodge star, (where is the electric current density, and is the electric charg
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https://en.wikipedia.org/wiki/Burnside%27s%20theorem
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In mathematics, Burnside's theorem in group theory states that if G is a finite group of order where p and q are prime numbers, and a and b are non-negative integers, then G is solvable. Hence each
non-Abelian finite simple group has order divisible by at least three distinct primes.
History
The theorem was proved by using the representation theory of finite groups. Several special cases of the theorem had previously been proved by Burnside, Jordan, and Frobenius. John Thompson pointed out that a proof avoiding the use of representation theory could be extracted from his work on the N-group theorem, and this was done explicitly by for groups of odd order, and by for groups of even order. simplified the proofs.
Proof
The following proof — using more background than Burnside's — is by contradiction. Let paqb be the smallest product of two prime powers, such that there is a non-solvable group G whose order is equal to this number.
G is a simple group with trivial center and a is not zero.
If G had a nontrivial proper normal subgroup H, then (because of the minimality of G), H and G/H would be solvable, so G as well, which would contradict our assumption. So G is simple.
If a were zero, G would be a finite q-group, hence nilpotent, and therefore solvable.
Similarly, G cannot be abelian, otherwise it would be solvable. As G is simple, its center must therefore be trivial.
There is an element g of G which has qd conjugates, for some d > 0.
By the first statement of Syl
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https://en.wikipedia.org/wiki/Integrating%20factor
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In mathematics, an integrating factor is a function that is chosen to facilitate the solving of a given equation involving differentials. It is commonly used to solve ordinary differential equations, but is also used within multivariable calculus when multiplying through by an integrating factor allows an inexact differential to be made into an exact differential (which can then be integrated to give a scalar field). This is especially useful in thermodynamics where temperature becomes the integrating factor that makes entropy an exact differential.
Use
An integrating factor is any expression that a differential equation is multiplied by to facilitate integration. For example, the nonlinear second order equation
admits as an integrating factor:
To integrate, note that both sides of the equation may be expressed as derivatives by going backwards with the chain rule:
Therefore,
where is a constant.
This form may be more useful, depending on application. Performing a separation of variables will give
This is an implicit solution which involves a nonelementary integral. This same method is used to solve the period of a simple pendulum.
Solving first order linear ordinary differential equations
Integrating factors are useful for solving ordinary differential equations that can be expressed in the form
The basic idea is to find some function, say , called the "integrating factor", which we can multiply through our differential equation in order to bring
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https://en.wikipedia.org/wiki/Olga%20Ladyzhenskaya
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Olga Aleksandrovna Ladyzhenskaya (; 7 March 1922 – 12 January 2004) was a Russian mathematician who worked on partial differential equations, fluid dynamics, and the finite difference method for the Navier–Stokes equations. She received the Lomonosov Gold Medal in 2002. She is the author of more than two hundred scientific works, among which are six monographs.
Biography
Ladyzhenskaya was born and grew up in the small town of Kologriv, the daughter of a mathematics teacher who is credited with her early inspiration and love of mathematics. The artist Gennady Ladyzhensky was her grandfather's brother, also born in this town. In 1937 her father, Aleksandr Ivanovich Ladýzhenski, was arrested by the NKVD and executed as an "enemy of the people".
Ladyzhenskaya completed high school in 1939, unlike her older sisters who weren't permitted to do the same. She was not admitted to the Leningrad State University due to her father's status and attended a pedagogical institute. After the German invasion of June 1941, she taught school in Kologriv. She was eventually admitted to Moscow State University in 1943 and graduated in 1947.
She began teaching in the Physics department of the university in 1950 and defended her PhD there, in 1951, under Sergei Sobolev and Vladimir Smirnov. She received a second doctorate from the Moscow State University in 1953. In 1954, she joined the mathematical physics laboratory of the Steklov Institute and became its head in 1961.
Ladyzhenskaya had a
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https://en.wikipedia.org/wiki/Nitrilase
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Nitrilase enzymes (nitrile aminohydrolase; ) catalyse the hydrolysis of nitriles to carboxylic acids and ammonia, without the formation of "free" amide intermediates. Nitrilases are involved in natural product biosynthesis and post translational modifications in plants, animals, fungi and certain prokaryotes. Nitrilases can also be used as catalysts in preparative organic chemistry. Among others, nitrilases have been used for the resolution of racemic mixtures. Nitrilase should not be confused with nitrile hydratase (nitrile hydro-lyase; ) which hydrolyses nitriles to amides. Nitrile hydratases are almost invariably co-expressed with an amidase, which converts the amide to the carboxylic acid. Consequently, it can sometimes be difficult to distinguish nitrilase activity from nitrile hydratase plus amidase activity.
Mechanism
Nitrilase was first discovered in the early 1960s for its ability to catalyze the hydration of a nitrile to a carboxylic acid. Although it was known at the time that nitrilase could operate with wide substrate specificity in producing the corresponding acid, later studies reported the first NHase (nitrile hydratase) activity exhibited by nitrilase. That is, amide compounds could also be formed via nitrile hydrolysis. Further research has revealed several conditions that promote amide formation, which are outlined below.
Early release of the enzyme-bound substrate after the first water hydrolysis followed by delayed addition of the second water
Low tem
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https://en.wikipedia.org/wiki/Permease
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The permeases are membrane transport proteins, a class of multipass transmembrane proteins that allow the diffusion of a specific molecule in or out of the cell in the direction of a concentration gradient, a form of facilitated diffusion.
The permease binding is the first step of translocation. LacY protein from Escherichia coli is an example of a permease.
See also
Lactose permease
Beta-galactoside permease
It was originally discovered in the 1930s by Joy Adames. It is a transporter protein that helps in various aspects of cellular life including DNA replication, translation of RNA, and diffusion.
Amino acid permease
A permease (porter) is a protein or protein complex that catalyzes a vectorial reaction, irrespective of whether or not it also catalyzes a chemical or electron transfer reaction that drives the vectorial process.
References
External links
Transport proteins
Transmembrane proteins
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https://en.wikipedia.org/wiki/Diversified%20financial
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Diversified financials is a specific category of the Global Industry Classification Standard (GICS) that is used by the financial community. It includes a range of consumer and commercially oriented companies offering a wide variety of financial products and services, including various lending products (such as home equity loans and credit cards), insurance, and securities and investment products.
Many of these firms in this category are non-banking financial companies, specialist organisations like stock exchanges or financial holding companies that were created through consolidation of banks, insurance companies and brokerage firms to become universal banks.
References
Financial services
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https://en.wikipedia.org/wiki/Off-the-record%20messaging
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Off-the-Record Messaging (OTR) is a cryptographic protocol that provides encryption for instant messaging conversations. OTR uses a combination of AES symmetric-key algorithm with 128 bits key length, the Diffie–Hellman key exchange with 1536 bits group size, and the SHA-1 hash function. In addition to authentication and encryption, OTR provides forward secrecy and malleable encryption.
The primary motivation behind the protocol was providing deniable authentication for the conversation participants while keeping conversations confidential, like a private conversation in real life, or off the record in journalism sourcing. This is in contrast with cryptography tools that produce output which can be later used as a verifiable record of the communication event and the identities of the participants. The initial introductory paper was named "Off-the-Record Communication, or, Why Not To Use PGP".
The OTR protocol was designed by cryptographers Ian Goldberg and Nikita Borisov and released on 26 October 2004. They provide a client library to facilitate support for instant messaging client developers who want to implement the protocol. A Pidgin and Kopete plugin exists that allows OTR to be used over any IM protocol supported by Pidgin or Kopete, offering an auto-detection feature that starts the OTR session with the buddies that have it enabled, without interfering with regular, unencrypted conversations. Version 4 of the protocol has been in development since 2017 by a team led
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https://en.wikipedia.org/wiki/Dielectric%20heating
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Dielectric heating, also known as electronic heating, radio frequency heating, and high-frequency heating, is the process in which a radio frequency (RF) alternating electric field, or radio wave or microwave electromagnetic radiation heats a dielectric material. At higher frequencies, this heating is caused by molecular dipole rotation within the dielectric.
Mechanism
Molecular rotation occurs in materials containing polar molecules having an electrical dipole moment, with the consequence that they will align themselves in an electromagnetic field. If the field is oscillating, as it is in an electromagnetic wave or in a rapidly oscillating electric field, these molecules rotate continuously by aligning with it. This is called dipole rotation, or dipolar polarisation. As the field alternates, the molecules reverse direction. Rotating molecules push, pull, and collide with other molecules (through electrical forces), distributing the energy to adjacent molecules and atoms in the material. The process of energy transfer from the source to the sample is a form of radiative heating.
Temperature is related to the average kinetic energy (energy of motion) of the atoms or molecules in a material, so agitating the molecules in this way increases the temperature of the material. Thus, dipole rotation is a mechanism by which energy in the form of electromagnetic radiation can raise the temperature of an object. There are also many other mechanisms by which this conversion occurs.
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https://en.wikipedia.org/wiki/Mean%20free%20time
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Molecules in a fluid constantly collide with each other. The mean free time for a molecule in a fluid is the average time between collisions. The mean free path of the molecule is the product of the average speed and the mean free time. These concepts are used in the kinetic theory of gases to compute transport coefficients such as the viscosity.
In a gas the mean free path may be much larger than the average distance between molecules. In a liquid these two lengths may be very similar.
Scattering is a random process. It is often modeled as a Poisson process, in which the probability of a collision in a small time interval is . For a Poisson process like this, the average time since the last collision, the average time until the next collision and the average time between collisions are all equal to .
References
Statistical mechanics
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https://en.wikipedia.org/wiki/Backup%20validation
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Backup validation is the process whereby owners of computer data may examine how their data was backed up in order to understand what their risk of data loss might be. It also speaks to optimization of such processes, charging for them as well as estimating future requirements, sometimes called capacity planning.
History
Over the past several decades (leading up to 2005), organizations (banks, governments, schools, manufacturers and others) have increased their reliance more on "Open Systems" and less on "Closed Systems". For example, 25 years ago, a large bank might have most if not all of its critical data housed in an IBM mainframe computer (a "Closed System"), but today, that same bank might store a substantially greater portion of its critical data in spreadsheets, databases, or even word processing documents (i.e., "Open Systems"). The problem with Open Systems is, primarily, their unpredictable nature. The very nature of an Open System is that it is exposed to potentially thousands if not millions of variables ranging from network overloads to computer virus attacks to simple software incompatibility. Any one, or indeed several in combination, of these factors may result in either lost data and/or compromised data backup attempts. These types of problems do not generally occur on Closed Systems, or at least, in unpredictable ways. In the "old days", backups were a nicely contained affair. Today, because of the ubiquity of, and dependence upon, Open Systems, an entire
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https://en.wikipedia.org/wiki/Williams%27s%20p%20%2B%201%20algorithm
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In computational number theory, Williams's p + 1 algorithm is an integer factorization algorithm, one of the family of algebraic-group factorisation algorithms. It was invented by Hugh C. Williams in 1982.
It works well if the number N to be factored contains one or more prime factors p such that p + 1 is smooth, i.e. p + 1 contains only small factors. It uses Lucas sequences to perform exponentiation in a quadratic field.
It is analogous to Pollard's p − 1 algorithm.
Algorithm
Choose some integer A greater than 2 which characterizes the Lucas sequence:
where all operations are performed modulo N.
Then any odd prime p divides whenever M is a multiple of , where
and
is the Jacobi symbol.
We require that , that is, D should be a quadratic non-residue modulo p. But as we don't know p beforehand, more than one value of A may be required before finding a solution. If , this algorithm degenerates into a slow version of Pollard's p − 1 algorithm.
So, for different values of M we calculate , and when the result is not equal to 1 or to N, we have found a non-trivial factor of N.
The values of M used are successive factorials, and is the M-th value of the sequence characterized by .
To find the M-th element V of the sequence characterized by B, we proceed in a manner similar to left-to-right exponentiation:
x := B
y := (B ^ 2 − 2) mod N
for each bit of M to the right of the most significant bit do
if the bit is 1 then
x := (x × y − B)
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https://en.wikipedia.org/wiki/Wildcoast
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Wildcoast (stylized WiLDCOAST) is an international non-profit environmental organization that conserves coastal and marine ecosystems and wildlife.
Headquartered in Del Mar, California, Wildcoast established a Mexican division in 2007, Costasalvaje A.C. in Ensenada to manage its conservation programs in Latin America.
Charity Navigator awarded Wildcoast its four-star charity ranking. The organization received the Excellence in Organizational Development Award from Nonprofit Management Solutions in 2006. It also received the San Diego Earthworks E.A.R.T.H. Award in 2007. In 2008, Wildcoast received the Green Wave Award from the Surfer's Path Magazine.
Campaigns
Demanding an end to ocean pollution - Wildcoast's Clean Water Now! page
Protecting sharks from exploitation - Wildcoast's Sharks... Killing Machines or Victims? page
Defending the sea from toxic waste and overfishing - Wildcoast's Defiende el Mar page
Saving endangered sea turtles - Wildcoast's Sea Turtles page
Preserving the beautiful San Ignacio Lagoon - Wildcoast's Laguna San Ignacio page
Conservation programs
Wildlands conservation
One of Wildcoast's primary missions is to preserve spectacular, undeveloped coastal areas throughout the peninsula of Baja California such as Bahía de los Ángeles, Bahía Concepción, Bahía Magdalena, Laguna San Ignacio and the North Central Pacific Coast. These are some of the most ecologically important coastal areas remaining on the planet and are teeming with wildlife inc
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https://en.wikipedia.org/wiki/Deoxyribozyme
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Deoxyribozymes, also called DNA enzymes, DNAzymes, or catalytic DNA, are DNA oligonucleotides that are capable of performing a specific chemical reaction, often but not always catalytic. This is similar to the action of other biological enzymes, such as proteins or ribozymes (enzymes composed of RNA).
However, in contrast to the abundance of protein enzymes in biological systems and the discovery of biological ribozymes in the 1980s,
there is only little evidence for naturally occurring deoxyribozymes.
Deoxyribozymes should not be confused with DNA aptamers which are oligonucleotides that selectively bind a target ligand, but do not catalyze a subsequent chemical reaction.
With the exception of ribozymes, nucleic acid molecules within cells primarily serve as storage of genetic information due to its ability to form complementary base pairs, which allows for high-fidelity copying and transfer of genetic information. In contrast, nucleic acid molecules are more limited in their catalytic ability, in comparison to protein enzymes, to just three types of interactions: hydrogen bonding, pi stacking, and metal-ion coordination. This is due to the limited number of functional groups of the nucleic acid monomers: while proteins are built from up to twenty different amino acids with various functional groups, nucleic acids are built from just four chemically similar nucleobases. In addition, DNA lacks the 2'-hydroxyl group found in RNA which limits the catalytic competency of deox
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https://en.wikipedia.org/wiki/UKF
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UKF may refer to:
Unscented Kalman filter, a special case of an algorithm to handle measurements containing noise and other inaccuracies
UK funky, a genre of electronic dance music from the United Kingdom
UKF Music, an electronic music brand based in the United Kingdom
United Kingdom First, a small short-lived populist, Eurosceptic British political party
Univerzita Konštantína Filozofa, a university in Nitra, Slovakia
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https://en.wikipedia.org/wiki/Yttrium%20orthovanadate
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Yttrium orthovanadate (YVO4) is a transparent crystal. Undoped YVO4 is also used to make efficient high-power polarizing prisms similar to Glan–Taylor prisms.
There are two principal applications for doped Yttrium orthovanadate:
Doped with neodymium it forms Nd:YVO4, an active laser medium used in diode-pumped solid-state lasers.
Doped with europium it forms Eu:YVO4, the dominant red phosphor used in cathode ray tubes especially in color TVs.
Basic properties
Crystal structure:
Zircon tetragonal (tetragonal bipyramidal)
Space group D4h
Lattice parameters a = b = 7.119 Å, c = 6.290 Å
Density: 4.24 g/cm3
Melting point: 1810–1940 °C
Mohs hardness: glass-like, ~5
Knoop hardness: 480 kg/mm2
Thermal expansion coefficient:
αa = 4.43×10−6/K
αc = 11.37×10−6/K
Thermal conductivity coefficient:
parallel to c-axis: 5.23 W·m−1·K−1
perpendicular to c-axis: 5.10 W·m−1·K−1
Refractive indices, birefringence ( Δn = ne - no) and walk-off angle at 45° (ρ):
at 0.63 μm:
ne = 2.2154
no = 1.9929
Δn = 0.2225
ρ = 6.04
at 1.30 μm:
ne = 2.1554
no = 1.9500
Δn = 0.2054
ρ= 5.72
at 1.55 μm:
ne = 2.1486
no = 1.9447
Δn = 0.2039
ρ = 5.69
Sellmeier equation (λ in μm):
ne2=4.59905 + 0.110534/(λ2 − 0.04813) − 0.012267612 λ2
no2=3.77834 + 0.069736/(λ2 − 0.04724) − 0.0108133 λ2
See also
Neodymium-doped yttrium orthovanadate
References
Vanadates
Yttrium compounds
Optical materials
Crystals
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https://en.wikipedia.org/wiki/Protein%20Information%20Resource
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The Protein Information Resource (PIR), located at Georgetown University Medical Center, is an integrated public bioinformatics resource to support genomic and proteomic research, and scientific studies. It contains protein sequences databases
History
PIR was established in 1984 by the National Biomedical Research Foundation as a resource to assist researchers and customers in the identification and interpretation of protein sequence information. Prior to that, the foundation compiled the first comprehensive collection of macromolecular sequences in the Atlas of Protein Sequence and Structure, published from 1964 to 1974 under the editorship of Margaret Dayhoff. Dayhoff and her research group pioneered in the development of computer methods for the comparison of protein sequences, for the detection of distantly related sequences and duplications within sequences, and for the inference of evolutionary histories from alignments of protein sequences.
Winona Barker and Robert Ledley assumed leadership of the project after the death of Dayhoff in 1983. In 1999, Cathy H. Wu joined the National Biomedical Research Foundation, and later on Georgetown University Medical Center, to head the bioinformatics efforts of PIR, and has served first as Principal Investigator and, since 2001, as Director.
For four decades, PIR has provided many protein databases and analysis tools freely accessible to the scientific community, including the Protein Sequence Database, the first international
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https://en.wikipedia.org/wiki/Death%20rattle
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Terminal respiratory secretions (or simply terminal secretions), known colloquially as a death rattle, are sounds often produced by someone who is near death as a result of fluids such as saliva and bronchial secretions accumulating in the throat and upper chest. Those who are dying may lose their ability to swallow and may have increased production of bronchial secretions, resulting in such an accumulation. Usually, two or three days earlier, the symptoms of approaching death can be observed as saliva accumulates in the throat, making it very difficult to take even a spoonful of water. Related symptoms can include shortness of breath and rapid chest movement. While death rattle is a strong indication that someone is near death, it can also be produced by other problems that cause interference with the swallowing reflex, such as brain injuries.
It is sometimes misinterpreted as the sound of the person choking to death or gargling.
Timing
This symptom most commonly appears sometime during the last 24 hours of the person's life, although some people live somewhat longer.
Management
The dying person is usually unaware of the noisy breathing and is not disturbed by it, but some healthcare providers attempt to minimize the sound for the emotional comfort of family members and caregivers. This may be done through repositioning the person, reducing the volume of IV fluids being given, or giving anticholinergic drugs to reduce secretions. In hospice and palliative care, drugs
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https://en.wikipedia.org/wiki/Utopia%20%28band%29
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Utopia was an American rock band formed in 1973 by Todd Rundgren. During its first three years, the group was a progressive rock band with a somewhat fluid membership known as Todd Rundgren's Utopia. Most of the members in this early incarnation also played on Rundgren's solo albums of the period up to 1975. By 1976, the group was known simply as Utopia and featured a stable quartet of Rundgren, Kasim Sulton, Roger Powell and John "Willie" Wilcox. This version of the group gradually abandoned progressive rock for more straightforward rock and pop.
In 1980, they had a top 40 hit with "Set Me Free". Though often thought of as a Rundgren-oriented project, all four members of Utopia wrote, sang, produced and performed on their albums; "Set Me Free", for example, was written and sung by Sulton. The group broke up in 1986, but reunited briefly in 1992. In 2011 the earlier prog-rock incarnation known as Todd Rundgren's Utopia was revived for a series of live shows. In 2018 Rundgren, Sulton, and Wilcox reunited for a tour with new keyboardist Gil Assayas under the moniker Todd Rundgren's Utopia.
History
Todd Rundgren's Utopia
On his 1973 album A Wizard, a True Star, Rundgren had sung the line "Wait another year, Utopia is here."
For a short period of time (1973–74) Todd Rundgren's Utopia consisted of Rundgren plus Hunt Sales and Tony Fox Sales together with the late David Mason (a musician from Florida, not to be confused with the former Traffic guitarist of the same name) and
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https://en.wikipedia.org/wiki/CHYZ-FM
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CHYZ-FM is the college radio station for Université Laval, located in Sainte-Foy, Québec, Canada. Its frequency is 94.3 MHz on the FM dial.
Formerly known as Radio Campus Laval, CHYZ-FM broadcasts in French. The station is run by volunteers, most of whom are Laval students. Station programming follows mostly a music radio format of many music genres.
After it was founded in 1991, when student radio programs from various university faculties merged to form Radio Campus Laval, the station launched its programming on closed circuit and cable FM. When it began broadcasting on the FM band in 1997, it became known by its call letters CHYZ. In 2000, it started broadcasting via the Internet. Since October 2005, CHYZ has been broadcasting with a 6000-watt antenna from a site at the university and, as a result, can now be heard on the FM band throughout the Greater Quebec City Area.
References
External links
CHYZ
Hyz
Hyz
Université Laval
Hyz
Radio stations established in 1997
1997 establishments in Quebec
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https://en.wikipedia.org/wiki/KUKA
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KUKA is a German manufacturer of industrial robots and factory automation systems owned by Chinese appliance manufacturer Midea Group.
The KUKA Robotics Corporation has 25 subsidiaries in the United States, Australia, Canada, Mexico, Brazil, China, Japan, South Korea, Taiwan, India, Russia and in various European countries. The company name, KUKA, is an acronym for .
KUKA Systems GmbH, a division of KUKA, is a supplier of engineering services and automated manufacturing systems with around 3,900 employees in twelve countries globally. KUKA Systems’ plants/equipments are being used by automotive manufacturers such as BMW, GM, Chrysler, Ford, Volvo, Volkswagen, Daimler AG and Valmet Automotive and by manufacturers from other industrial sectors such as Airbus, Astrium and Siemens. The range includes products and services for task automation in the industrial processing of metallic and non-metallic materials for various industries including automotive, energy, aerospace, rail vehicles, and agricultural machinery.
History
The acetylene factory Augsburg was founded in 1898 in Augsburg, Germany, by Johann Josef Keller and Jakob Knappich for the production of low-cost domestic and municipal lighting, household appliances and automobile headlights. In 1905, the production was extended to the innovative autonomous welding equipment. After the First World War, Keller and Knappich resumed production of safety-, manual- and power-winches and began the manufacturing of large containe
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https://en.wikipedia.org/wiki/Carrierless%20amplitude%20phase%20modulation
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Carrierless amplitude phase modulation (CAP) is a variant of quadrature amplitude modulation (QAM). Instead of modulating the amplitude of two carrier waves, CAP generates a QAM signal by combining two PAM signals filtered through two filters designed so that their impulse responses form a Hilbert pair. If the impulse responses of the two filters are chosen as sine and a cosine, the only mathematical difference between QAM and CAP waveforms is that the phase of the carrier is reset at the beginning of each symbol. If the carrier frequency and symbol rates are similar, the main advantage of CAP over QAM is simpler implementation. The modulation of the baseband signal with the quadrature carriers is not necessary with CAP, because it is part of the transmit pulse.
Applications
CAP finds application in HDSL and in early proprietary ADSL variants. For HDSL, the American ANSI standard specifies 2B1Q rather than CAP, while the European ETSI ETR 152 and the international ITU-T G.991.2 standards specify both CAP and 2B1Q. For ADSL deployments CAP was the de facto standard up until 1996, deployed in 90 percent of ADSL installs. The standardized variants of ADSL, ANSI T1.413 Issue 2 and G.dmt, as well as the successors ADSL2, ADSL2+, VDSL2, and G.fast, do not specify CAP, but rather discrete multi-tone (DMT) modulation.
CAP used for ADSL divides the available frequency spectrum into three bands. The range from 0 to 4 kHz is allocated for POTS transmissions. The range of 25 kHz to 160
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https://en.wikipedia.org/wiki/FOXP3
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FOXP3 (forkhead box P3), also known as scurfin, is a protein involved in immune system responses. A member of the FOX protein family, FOXP3 appears to function as a master regulator of the regulatory pathway in the development and function of regulatory T cells. Regulatory T cells generally turn the immune response down. In cancer, an excess of regulatory T cell activity can prevent the immune system from destroying cancer cells. In autoimmune disease, a deficiency of regulatory T cell activity can allow other autoimmune cells to attack the body's own tissues.
While the precise control mechanism has not yet been established, FOX proteins belong to the forkhead/winged-helix family of transcriptional regulators and are presumed to exert control via similar DNA binding interactions during transcription. In regulatory T cell model systems, the FOXP3 transcription factor occupies the promoters for genes involved in regulatory T-cell function, and may inhibit transcription of key genes following stimulation of T cell receptors.
Structure
The human FOXP3 genes contain 11 coding exons. Exon-intron boundaries are identical across the coding regions of the mouse and human genes. By genomic sequence analysis, the FOXP3 gene maps to the p arm of the X chromosome (specifically, Xp11.23).
Physiology
Foxp3 is a specific marker of natural T regulatory cells (nTregs, a lineage of T cells) and adaptive/induced T regulatory cells (a/iTregs), also identified by other less specific markers
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https://en.wikipedia.org/wiki/Mcrypt
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mcrypt is a replacement for the popular Unix crypt command. crypt was a file encryption tool that used an algorithm very close to the World War II Enigma cipher. Mcrypt provides the same functionality but uses several modern algorithms such as AES. Libmcrypt, Mcrypt's companion, is a library of code that contains the actual encryption functions and provides an easy method for use. The last update to libmcrypt was in 2007, despite years of unmerged patches. Maintained alternatives include ccrypt, libressl, and others.
Examples of mcrypt usage in a Linux command-line environment:
mcrypt --list # See available encryption algorithms.
mcrypt -a blowfish myfilename # Encrypts myfilename to myfilename.nc
# using the Blowfish encryption algorithm.
# You are prompted two times for a passphrase.
mcrypt -d mytextfile.txt.nc # Decrypts mytextfile.txt.nc to mytextfile.txt.
mcrypt -V -d -a enigma -o scrypt --bare # Can en/decrypt files crypted with SunOS crypt.
mcrypt --help
It implements numerous cryptographic algorithms, mostly block ciphers and stream ciphers, some of which fall under export restrictions in the United States. Algorithms include DES, Blowfish, ARCFOUR, Enigma, GOST, LOKI97, RC2, Serpent, Threeway, Twofish, WAKE, and XTEA.
See also
bcrypt
crypt (Unix)
ccrypt
scrypt
References
External links
The
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https://en.wikipedia.org/wiki/Diphasiastrum
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Diphasiastrum is a genus of clubmosses in the plant family Lycopodiaceae. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), it is placed in the subfamily Lycopodioideae. It is closely related to the genus Lycopodium, and some botanists treat it within a broad view of that genus as a section, Lycopodium sect. Complanata. Some species superficially resemble diminutive gymnosperms and have been given common names such as ground-pine or ground-cedar.
There are 16 species, and numerous natural hybrids in the genus; many of the hybrids are fertile, allowing their occurrence to become frequent, sometimes more so than the parent species. The basal chromosome count for this genus is n=23, which is distinctively different from other lycopods.
Several species have been used economically for their spores, which are harvested as Lycopodium powder.
Species
, the Checklist of Ferns and Lycophytes of the World recognized the following species:
Diphasiastrum alpinum (L.) Holub – alpine clubmoss; circumpolar, subarctic and alpine
Diphasiastrum angustiramosum (Alderw.) Holub – New Guinea
Diphasiastrum carolinum (Lawalrée) Holub
Diphasiastrum complanatum (L.) Holub – flat-stemmed clubmoss, northern running-pine, or ground cedar; circumpolar, cool temperate
Diphasiastrum digitatum (Dill. ex A.Br.) Holub – fan clubmoss, southern running-pine, or running cedar; eastern Canada, northeastern United States, Appalachian Mountains
Diphasiastrum falcatum B.Øllg. & P.G.Windisch
Dip
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https://en.wikipedia.org/wiki/Ram%20pressure
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Ram pressure is a pressure exerted on a body moving through a fluid medium, caused by relative bulk motion of the fluid rather than random thermal motion. It causes a drag force to be exerted on the body. Ram pressure is given in tensor form as
,
where is the density of the fluid; is the momentum flux per second in the direction through a surface with normal in the direction. are the components of the fluid velocity in these directions. The total Cauchy stress tensor is the sum of this ram pressure and the isotropic thermal pressure (in the absence of viscosity).
In the simple case when the relative velocity is normal to the surface, and momentum is fully transferred to the object, the ram pressure becomes
.
Derivation
The Eulerian form of the Cauchy momentum equation for a fluid is
for isotropic pressure , where is fluid velocity, the fluid density, and the gravitational acceleration. The Eulerian rate of change of momentum in direction at a point is thus (using Einstein notation):
Substituting the conservation of mass, expressed as
,
this is equivalent to
using the product rule and the Kronecker delta . The first term in the brackets is the isotropic thermal pressure, and the second is the ram pressure.
In this context, ram pressure is momentum transfer by advection (flow of matter carrying momentum across a surface into a body). The mass per unit second flowing into a volume bounded by a surface is
and the momentum per second it carries into the
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https://en.wikipedia.org/wiki/High-throughput
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High-throughput may refer to:
High-throughput computing, a computer science concept
High-throughput screening, a bioinformatics concept
High-throughput biology, a cell biology concept
High-throughput sequencing, DNA sequencing
Measuring data throughput, a communications concept
See also
Throughput
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https://en.wikipedia.org/wiki/Carbonate%20rock
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Carbonate rocks are a class of sedimentary rocks composed primarily of carbonate minerals. The two major types are limestone, which is composed of calcite or aragonite (different crystal forms of CaCO3), and dolomite rock (also known as dolostone), which is composed of mineral dolomite (CaMg(CO3)2). They are usually classified based on texture and grain size. Importantly, carbonate rocks can exist as metamorphic and igneous rocks, too. When recrystallized carbonate rocks are metamorphosed, marble is created. Rare igneous carbonate rocks even exist as intrusive carbonatites and, even rarer, there exists volcanic carbonate lava.
Carbonate rocks are also crucial components to understanding geologic history due to processes such as diagenesis in which carbonates undergo compositional changes based on kinetic effects. The correlation between this compositional change and temperature can be exploited to reconstruct past climate as is done in paleoclimatology. Carbonate rocks can also be used for understanding various other systems as described below.
Limestone
Limestone is the most common carbonate rock and is a sedimentary rock made of calcium carbonate with two main polymorphs: calcite and aragonite. While the chemical composition of these two minerals is the same, their physical properties differ significantly due to their different crystalline form. The most common form found in the seafloor is calcite, while aragonite is more found in biological organisms.
Calcite
Calci
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https://en.wikipedia.org/wiki/Semiconductor%20Manufacturing%20International%20Corporation
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Semiconductor Manufacturing International Corporation (SMIC) is a partially state-owned publicly listed Chinese pure-play semiconductor foundry company. It is the largest contract chip maker in mainland China.
SMIC is headquartered in Shanghai and incorporated in the Cayman Islands. It has wafer fabrication sites throughout mainland China, offices in the United States, Italy, Japan, and Taiwan, and a representative office in Hong Kong. It provides integrated circuit (IC) manufacturing services from 350 nm to 7 nm process technologies.
State-owned civilian and military telecommunications equipment provider Datang Telecom Group as well as the China Integrated Circuit Industry Investment Fund are major shareholders of SMIC. Notable customers include Huawei, Qualcomm, Broadcom, and Texas Instruments. SMIC expanded in the early 2020s by building four 28 nm process fabs across China as a result of a joint venture with China's state semiconductor fund; the fabs were expected to come online in 2023 and 2024.
History
SMIC was founded on April 3, 2000, and is headquartered in Shanghai. It was incorporated in the Cayman Islands as a limited liability company. It quickly built a fully-owned plant in Shanghai, acquired a Motorola plant in Tianjin, and then began to build a fully-owned plant in Beijing. SMIC also became involved in two projects in Chengdu and Wuhan, which reversed a common pattern in Chinese development of government building, operating, then transferring industrial
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https://en.wikipedia.org/wiki/Fire%20ecology
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Fire ecology is a scientific discipline concerned with the effects of fire on natural ecosystems. Many ecosystems, particularly prairie, savanna, chaparral and coniferous forests, have evolved with fire as an essential contributor to habitat vitality and renewal. Many plant species in fire-affected environments use fire to germinate, establish, or to reproduce. Wildfire suppression not only endangers these species, but also the animals that depend upon them.
Wildfire suppression campaigns in the United States have historically molded public opinion to believe that wildfires are harmful to nature. Ecological research has shown, however, that fire is an integral component in the function and biodiversity of many natural habitats, and that the organisms within these communities have adapted to withstand, and even to exploit, natural wildfire. More generally, fire is now regarded as a 'natural disturbance', similar to flooding, windstorms, and landslides, that has driven the evolution of species and controls the characteristics of ecosystems.
Fire suppression, in combination with other human-caused environmental changes, may have resulted in unforeseen consequences for natural ecosystems. Some large wildfires in the United States have been blamed on years of fire suppression and the continuing expansion of people into fire-adapted ecosystems as well as climate change. Land managers are faced with tough questions regarding how to restore a natural fire regime, but allowing wil
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https://en.wikipedia.org/wiki/Crystal%20Waters
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Crystal Waters (born November 19, 1961) is an American house and dance music singer and songwriter, best known for her 1990s dance hits "Gypsy Woman", "100% Pure Love", and 2007's "Destination Calabria" with Alex Gaudino. All three of her studio albums produced a Top 40 hit on the Billboard Hot 100. In December 2016, Billboard magazine ranked her as one of the most successful dance artists of all time. Her accolades include six ASCAP Songwriter awards, three American Music Award nominations, an MTV Video Music Award nod, four Billboard Music Awards and twelve No. 1 Billboard Dance Chart hits. Her hit song "Gypsy Woman” has been sampled hundreds of times. Though her music sales have yet to be re-certified, Waters has sold over 7 million records worldwide.
Life and career
Early life
Born in Deptford Township, New Jersey, Waters is the daughter of Junior Waters, a famed jazz musician, and his wife Betty. Her great-aunt, Ethel Waters, was one of the first black American vocalists to appear in mainstream Hollywood musicals. Her family moved to New Jersey for a while but they again moved to Washington, D.C. At age eleven she began writing poetry and took her writing seriously enough to be inducted into the Poetry Society of America when she was 14, the youngest person ever to receive that honor.
She studied business and computer science at Howard University, but her creative work as a musician dropped off as she found less time for it. After earning her college degree in 1989, W
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https://en.wikipedia.org/wiki/Arsanilic%20acid
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Arsanilic acid, also known as aminophenyl arsenic acid or aminophenyl arsonic acid, is an organoarsenic compound, an amino derivative of phenylarsonic acid whose amine group is in the 4-position. A crystalline powder introduced medically in the late 19th century as Atoxyl, its sodium salt was used by injection in the early 20th century as the first organic arsenical drug, but it was soon found prohibitively toxic for human use.
Arsanilic acid saw long use as a veterinary feed additive promoting growth and to prevent or treat dysentery in poultry and swine. In 2013, its approval by US government as an animal drug was voluntarily withdrawn by its sponsors. Still sometimes used in laboratories, arsanilic acid's legacy is principally through its influence on Paul Ehrlich in launching the antimicrobial chemotherapy approach to treating infectious diseases of humans.
Chemistry
Synthesis was first reported in 1863 by Antoine Béchamp and became the basis of the Bechamp reaction. The process involves the reaction of aniline and arsenic acid via an electrophilic aromatic substitution reaction.
C6H5NH2 + H3AsO4 → H2O3AsC6H4NH2 + H2O
Arsanilic acid occurs as a zwitterion, H3N+C6H4AsO3H−, yet is typically represented with the non-zwitterionic formula H2NC6H4AsO3H2.
History
Roots and synthesis
Since at least 2000 BC, arsenic and inorganic arsenical compounds were both medicine and poison. In the 19th century, inorganic arsenicals became the preeminent medicines, for instan
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https://en.wikipedia.org/wiki/Plug%20flow
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In fluid mechanics, plug flow is a simple model of the velocity profile of a fluid flowing in a pipe. In plug flow, the velocity of the fluid is assumed to be constant across any cross-section of the pipe perpendicular to the axis of the pipe. The plug flow model assumes there is no boundary layer adjacent to the inner wall of the pipe.
The plug flow model has many practical applications. One example is in the design of chemical reactors. Essentially no back mixing is assumed with "plugs" of fluid passing through the reactor. This results in differential equations that need to be integrated to find the reactor conversion and outlet temperatures. Other simplifications used are perfect radial mixing and a homogeneous bed structure.
An advantage of the plug flow model is that no part of the solution of the problem can be perpetuated "upstream". This allows one to calculate the exact solution to the differential equation knowing only the initial conditions. No further iteration is required. Each "plug" can be solved independently provided the previous plug's state is known.
The flow model in which the velocity profile consists of the fully developed boundary layer is known as pipe flow. In laminar pipe flow, the velocity profile is parabolic.
Determination
For flows in pipes, if flow is turbulent then the laminar sublayer caused by the pipe wall is so thin that it is negligible. Plug flow will be achieved if the sublayer thickness is much less than the pipe diameter
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https://en.wikipedia.org/wiki/Abraham%20Lempel
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Abraham Lempel (; 10 February 1936 – 4 February 2023) was an Israeli computer scientist and one of the fathers of the LZ family of lossless data compression algorithms.
Biography
Lempel was born on 10 February 1936 in Lwów, Poland (now Lviv, Ukraine). He studied at Technion - Israel Institute of Technology, and received a B.Sc. in 1963, an M.Sc. in 1965, and a D.Sc. in 1967. Since 1977 he held the title of full professor, and was a professor emeritus at Technion.
His historically-important works start with the presentation of the LZ77 algorithm in a paper entitled "A Universal Algorithm for Sequential Data Compression" in the IEEE Transactions on Information Theory (May 1977), co-authored by Jacob Ziv.
Lempel was the recipient of the 1998 Golden Jubilee Award for Technological Innovation from the IEEE Information Theory Society; and the 2007 IEEE Richard W. Hamming Medal for "pioneering work in data compression, especially the Lempel-Ziv algorithm".
Lempel founded HP Labs—Israel in 1994, and served as its director until October 2007.
Lempel died on 4 February 2023, one week before his 87th birthday.
Works
The LZ77 and LZ78 algorithms authored by Lempel and Jacob Ziv have led to a number of derivative works, including the Lempel–Ziv–Welch algorithm, used in the GIF image format, and the Lempel-Ziv-Markov chain algorithm, used in the 7-Zip and xz compressors. The algorithms have also been used as originally published in formats such as DEFLATE, used in the PNG image form
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https://en.wikipedia.org/wiki/Federal%20State%20Statistics%20Service%20%28Russia%29
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The Federal State Statistics Service (, Росстат/Rosstat) is the governmental statistics agency in Russia.
Since 2017, it is again part of the Ministry of Economic Development, having switched several times in the previous decades between that ministry and being directly controlled by the federal government.
History
Goskomstat (, or, in English, the State Committee for Statistics) was the centralised agency dealing with statistics in the Soviet Union. Goskomstat was created in 1987 to replace the Central Statistical Administration, while maintaining the same basic functions in the collection, analysis, publication and distribution of state statistics, including economic, social and population statistics. This renaming amounted to a formal demotion of the status of the agency.
In addition to overseeing the collection and evaluation of state statistics, Goskomstat (and its predecessors) was responsible for planning and carrying out the population and housing censuses. It carried out seven such censuses, in 1926, 1937, 1939, 1959, 1970, 1979 and 1989.
House No. 39, on Ulitsa Myasnitskaya, Tsentrosoyuz building, home to Goskomstat, was designed by the Swiss-born architect Le Corbusier.
References
External links
Official website
Official website
Interstate Statistical Committee of the Commonwealth of Independent States
Government agencies of Russia
Economy of the Soviet Union
Government of the Soviet Union
1987 establishments in the Soviet Union
State Committees of th
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https://en.wikipedia.org/wiki/PragVEC
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PragVEC was a post-punk band from London formed in 1978. The band name was a contraction of the two words "pragmatism" and "vector", chosen at random.
History
PragVEC were formed in February 1978 by ex-Derelicts members Susan Gogan (vocals, synthesizer) and John Studholme guitar, synthesizer, along with David Boyd (bass) and Nicholas Cash (drums).
On 16 October 1978, they released their debut EP, the four-song 7-inch Bits, on their own Spec Records label. It was followed on 10 July 1979 by the "Expert" single. Both records were compiled on an eponymous 12-inch EP issued on the French label Celluloid Records.
PragVEC played concerts during 1978 and 1979, opening for bands such as Cabaret Voltaire, Scritti Politti, the Psychedelic Furs, the Monochrome Set, Au Pairs, Magazine, Chelsea, Stiff Little Fingers and the Teardrop Explodes.
During their short existence, they also recorded a total of three sessions for the John Peel programme. The last of these showed them moving away from the guitar-based sound of the first EP towards the use of the Wasp, a battery-powered portable synthesizer with a built-in speaker. Two of the songs, "Rural Erotic" and "Third Person", were re-recorded for the No-Cowboys album, released in December 1980. Packaged in a polythene bag, the record was presented as a compilation by various bands, although all of the material was recorded by PragVEC.
The band split in 1981, with Cash joining Fad Gadget and the Lines. Gogan joined the Atoms. Jim Thirlwe
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https://en.wikipedia.org/wiki/Ch%C3%A9nier%20Cell
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The Chénier Cell, also known as the South Shore Gang, was a Montreal-based Front de libération du Québec (FLQ) terrorist cell responsible for a decade of bombing, armed robbery and kidnapping that led to the October Crisis.
Background
The Chénier Cell was named after the Lower Canada Rebellion patriote movement leader Jean-Olivier Chénier. A violent Quebec sovereignty movement, the Chénier Cell attempted to usurp the elected Government of Quebec and create a Québécois people's uprising to establish a new Quebec state independent of Canada. The four known members of the Chénier Cell were: Paul Rose, Jacques Rose, Francis Simard and Bernard Lortie.
Timeline
On October 5, 1970, members of another Montreal-based FLQ cell, the Liberation Cell, kidnapped the United Kingdom Trade Commissioner James Richard Cross from his Montreal home.
On October 8, 1970, the FLQ Manifesto was broadcast by CBC/Radio-Canada as one of the many demands required for the release of James Cross. The manifesto criticised big business, the Catholic Church, René Lévesque, Robert Bourassa and declared Pierre Trudeau "a queer".
On October 10, 1970, the Chénier Cell kidnapped the Vice-Premier of Quebec and Labour Minister, Pierre Laporte. The kidnappers approached Laporte, while he was playing football with his nephew on his front yard and forced him into their vehicle at gunpoint. The members of the Chénier Cell believed many other Québécois people would follow them in an uprising to create an independent
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https://en.wikipedia.org/wiki/Thermostabilization
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Thermostabilization may refer to:
In the food industry - preservation by heat, usually under pressure. The heat destroys all microorganisms and alters the catalytic activity of the enzymes.
In molecular biology - the resistance to heat of a molecule (enzyme).
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https://en.wikipedia.org/wiki/Tiliaceae
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Tiliaceae () is a family of flowering plants. It is not a part of the APG, APG II and APG III classifications, being sunk in Malvaceae mostly as the subfamilies Tilioideae, Brownlowioideae and Grewioideae, but has an extensive historical record of use.
All through its existence the family has had a very lively history, with various authors taking very different views on what should be part of this family. As a result, it is recommended when this name is encountered to check what the author means.
However, in the northern temperate regions the name is unambiguous as the only representative is Tilia, the lime or linden.
APG II system
The APG II system, does not recognise this as a family but submerges it in the Malvaceae sensu lato, which unites the four families Bombacaceae, Malvaceae sensu stricto, Sterculiaceae and Tiliaceae. Modern botanical taxonomy, such as the relevant volume in the Kubitzki series which conforms to APG, treats most of the plants that traditionally constitute the family (see above) in the subfamilies Tilioideae, Brownlowioideae, and Grewioideae within this extended family Malvaceae sensu lato. Cladistically, the traditional family Tiliaceae is polyphyletic.
de Candolle system
In the de Candolle system the circumscription of the family was:
family Tiliaceae
genus I. Sparmannia [sic: now Sparrmannia]
genus II? Abatia
genus III. Heliocarpus
genus IV. Antichorus
genus V. Corchorus
genus VI. Honckenya [sic, see Clappertonia]
genus VII. Triumfetta
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https://en.wikipedia.org/wiki/Per%20Martin-L%C3%B6f
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Per Erik Rutger Martin-Löf (; ; born 8 May 1942) is a Swedish logician, philosopher, and mathematical statistician. He is internationally renowned for his work on the foundations of probability, statistics, mathematical logic, and computer science. Since the late 1970s, Martin-Löf's publications have been mainly in logic. In philosophical logic, Martin-Löf has wrestled with the philosophy of logical consequence and judgment, partly inspired by the work of Brentano, Frege, and Husserl. In mathematical logic, Martin-Löf has been active in developing intuitionistic type theory as a constructive foundation of mathematics; Martin-Löf's work on type theory has influenced computer science.
Until his retirement in 2009, Per Martin-Löf held a joint chair for Mathematics and Philosophy at Stockholm University.
His brother Anders Martin-Löf is now emeritus professor of mathematical statistics at Stockholm University; the two brothers have collaborated in research in probability and statistics. The research of Anders and Per Martin-Löf has influenced statistical theory, especially concerning exponential families, the expectation-maximization method for missing data, and model selection.
Per Martin-Löf received his PhD in 1970 from Stockholm University, under Andrey Kolmogorov.
Martin-Löf is an enthusiastic bird-watcher; his first scientific publication was on the mortality rates of ringed birds.
Randomness and Kolmogorov complexity
In 1964 and 1965, Martin-Löf studied in Moscow un
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https://en.wikipedia.org/wiki/John%20Gofman
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John William Gofman (21 September 1918 – 15 August 2007) was an American scientist and advocate. He was Professor Emeritus of Molecular and Cell Biology at the University of California at Berkeley.
Gofman pioneered the field of clinical lipidology, and in 2007 was honored by the Journal of Clinical Lipidology with the title of "Father of Clinical Lipidology". With Frank T. Lindgren and other research associates, Gofman discovered and described three major classes of plasma lipoproteins, fat molecules that carry cholesterol in the blood. The team he led at the Donner Laboratory went on to demonstrate the role of lipoproteins in the causation of heart disease.
Gofman was instrumental in inducing the health-physics scientific community both to acknowledge the cancer risks of ionizing radiation and to adopt the Linear No-Threshold (LNT) model as a means of estimating actual cancer risks from low-level radiation and as the foundation of the international guidelines for radiation protection. However, his conclusions were that the dose-response relationship was not linear, but supra-linear.
Gofman's earliest research was in nuclear physics and chemistry, in close connection with the Manhattan Project. He codiscovered several radioisotopes, notably uranium-233 and its fissionability; he was the third person ever to work with plutonium and, having devised an early process for separating plutonium from fission products at J. Robert Oppenheimer's request, he was the first chemist eve
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https://en.wikipedia.org/wiki/Electron%20paramagnetic%20resonance
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Electron paramagnetic resonance (EPR) or electron spin resonance (ESR) spectroscopy is a method for studying materials that have unpaired electrons. The basic concepts of EPR are analogous to those of nuclear magnetic resonance (NMR), but the spins excited are those of the electrons instead of the atomic nuclei. EPR spectroscopy is particularly useful for studying metal complexes and organic radicals. EPR was first observed in Kazan State University by Soviet physicist Yevgeny Zavoisky in 1944, and was developed independently at the same time by Brebis Bleaney at the University of Oxford.
Theory
Origin of an EPR signal
Every electron has a magnetic moment and spin quantum number , with magnetic components or . In the presence of an external magnetic field with strength , the electron's magnetic moment aligns itself either antiparallel () or parallel () to the field, each alignment having a specific energy due to the Zeeman effect:
where
is the electron's so-called g-factor (see also the Landé g-factor), for the free electron,
is the Bohr magneton.
Therefore, the separation between the lower and the upper state is for unpaired free electrons. This equation implies (since both and are constant) that the splitting of the energy levels is directly proportional to the magnetic field's strength, as shown in the diagram below.
An unpaired electron can change its electron spin by either absorbing or emitting a photon of energy such that the resonance condition, , is ob
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https://en.wikipedia.org/wiki/Radical%20anion
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In organic chemistry, a radical anion is a free radical species that carries a negative charge. Radical anions are encountered in organic chemistry as reduced derivatives of polycyclic aromatic compounds, e.g. sodium naphthenide. An example of a non-carbon radical anion is the superoxide anion, formed by transfer of one electron to an oxygen molecule. Radical anions are typically indicated by .
Polycyclic radical anions
Many aromatic compounds can undergo one-electron reduction by alkali metals. The electron is transferred from the alkali metal ion to an unoccupied antibonding p-p п* orbital of the aromatic molecule. This transfer is usually only energetically favorable if the aprotic solvent efficiently solvates the alkali metal ion. Effective solvents are those that bind to the alkali metal cation: diethyl ether < THF < 1,2-dimethoxyethane < HMPA. In principle any unsaturated molecule can form a radical anion, but the antibonding orbitals are only energetically accessible in more extensive conjugated systems. Ease of formation is in the order benzene < naphthalene < anthracene < pyrene, etc. Salts of the radical anions are often not isolated as solids but used in situ. They are usually deeply colored.
Naphthalene in the form of
Lithium naphthalene is obtained from the reaction of naphthalene with lithium.
Sodium naphthalene is obtained from the reaction of naphthalene with sodium.
Sodium 1-methylnaphthalene and 1-methylnaphthalene are more soluble than sodium napht
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https://en.wikipedia.org/wiki/Proflavine
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Proflavine, also called proflavin and diaminoacridine, is an acriflavine derivative, a disinfectant bacteriostatic against many gram-positive bacteria. It has been used in the form of the dihydrochloride and hemisulfate salts as a topical antiseptic, and was formerly used as a urinary antiseptic.
Proflavine is also known to have a mutagenic effect on DNA by intercalating between nucleic acid base pairs. It differs from most other mutagenic components by causing basepair-deletions or basepair-insertions and not substitutions. In the presence of light, proflavine can induce double-stranded breaks in DNA.
Proflavine absorbs strongly in the blue region at 445 nm (in water at pH 7) with molar extinction coefficient of c. 40,000.
Proflavin is a fluorescent dye that is sometimes used in microscopic in-vivo imaging due to its intercalation properties. However, there was concern that women exposed to proflavin could develop cervical cancer since they have mutagenesis potential. However, the retrospective analysis performed by Pantano et. al. demonstrated that there is no increased cervical cancer risk after exposure to proflavin.
References
Antiseptics
Acridines
DNA intercalaters
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https://en.wikipedia.org/wiki/European%20river%20zonation
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The classification of European rivers comes from the fish fauna found in them. Changes in taxonomic composition relate to physical and chemical changes that occur longitudinally.
Zonation (from headwater to estuary)
Trout zone
This zone has a characteristic steep gradient, fast flowing water and cool temperature. The fast flow rate causes turbulence which keeps the water well oxygenated. Fish species found in this zone usually lay adhesive eggs that can stick to the substrate, this is to help prevent eggs being carried down stream by the water flow.
Characteristic fish species are:
Brown trout (Salmo trutta)
Atlantic salmon (Salmo salar)
Bullhead (Cottus gobio)
Loach (Barbatula barbatula)
Grayling zone
Similar in physical characteristics to the Trout zone, although the temperature is usually slightly higher. Fish species in this zone also lay adhesive eggs.
Characteristic fish species include all of the above species, with the addition of;
Grayling (Thymallus thymallus)
Minnow (Phoxinus phoxinus)
Chub (Leuciscus cephalus)
Dace (Leuciscus leuciscus)
Barbel zone
This zone is essentially lowland, but retains some characteristics of upland rivers. It has a gentle gradient with a moderate water flow and temperature. It also has a good oxygen content and a mixed substrate of silt and gravel in which plants can take root. Most of the fish species found in this zone lay their eggs in the vegetation on the river bed, this provides them with good protection and allows
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https://en.wikipedia.org/wiki/Broyden%E2%80%93Fletcher%E2%80%93Goldfarb%E2%80%93Shanno%20algorithm
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In numerical optimization, the Broyden–Fletcher–Goldfarb–Shanno (BFGS) algorithm is an iterative method for solving unconstrained nonlinear optimization problems. Like the related Davidon–Fletcher–Powell method, BFGS determines the descent direction by preconditioning the gradient with curvature information. It does so by gradually improving an approximation to the Hessian matrix of the loss function, obtained only from gradient evaluations (or approximate gradient evaluations) via a generalized secant method.
Since the updates of the BFGS curvature matrix do not require matrix inversion, its computational complexity is only , compared to in Newton's method. Also in common use is L-BFGS, which is a limited-memory version of BFGS that is particularly suited to problems with very large numbers of variables (e.g., >1000). The BFGS-B variant handles simple box constraints.
The algorithm is named after Charles George Broyden, Roger Fletcher, Donald Goldfarb and David Shanno.
Rationale
The optimization problem is to minimize , where is a vector in , and is a differentiable scalar function. There are no constraints on the values that can take.
The algorithm begins at an initial estimate for the optimal value and proceeds iteratively to get a better estimate at each stage.
The search direction pk at stage k is given by the solution of the analogue of the Newton equation:
where is an approximation to the Hessian matrix at , which is updated iteratively at each stage, and
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https://en.wikipedia.org/wiki/RIVPACS
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RIVPACS (River Invertebrate Prediction and Classification System) is an aquatic biomonitoring system for assessing water quality in freshwater rivers in the United Kingdom. It is based on the macroinvertebrate species (such as freshwater shrimp, freshwater sponges, worms, crayfish, aquatic snails, freshwater mussels, insects, and many others) found at the study site during sampling. Some of these species are tolerant to pollution, low dissolved oxygen, and other stressors, but others are sensitive; organisms vary in their tolerances. Therefore, different species will usually be found, in different proportions, at different river sites of varying quality. Some organisms are especially good indicator species. The species found at the reference sites collectively make up the species assemblage for that site and are the basis for a statistical comparison between reference sites and non-reference sites. The comparison between the expected species and the observed species can then be used to estimate this aspect of the ecological health of a river.
The system is meant to be standardized, easy to use, and relatively low cost. It can complement other types of water quality monitoring such as chemical monitoring. RIVPACS supports the implementation of the Water Framework Directive as its official tool for macroinvertebrate classification
Reference sites can be chosen and adjusted several ways. Usually they represent the best conditions within the region or area under study, and are
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https://en.wikipedia.org/wiki/Goldman%20equation
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The Goldman–Hodgkin–Katz voltage equation, sometimes called the Goldman equation, is used in cell membrane physiology to determine the reversal potential across a cell's membrane, taking into account all of the ions that are permeant through that membrane.
The discoverers of this are David E. Goldman of Columbia University, and the Medicine Nobel laureates Alan Lloyd Hodgkin and Bernard Katz.
Equation for monovalent ions
The GHK voltage equation for monovalent positive ionic species and negative:
This results in the following if we consider a membrane separating two -solutions:
It is "Nernst-like" but has a term for each permeant ion:
= the membrane potential (in volts, equivalent to joules per coulomb)
= the selectivity for that ion (in meters per second)
= the extracellular concentration of that ion (in moles per cubic meter, to match the other SI units)
= the intracellular concentration of that ion (in moles per cubic meter)
= the ideal gas constant (joules per kelvin per mole)
= the temperature in kelvins
= Faraday's constant (coulombs per mole)
is approximately 26.7 mV at human body temperature (37 °C); when factoring in the change-of-base formula between the natural logarithm, ln, and logarithm with base 10 , it becomes , a value often used in neuroscience.
The ionic charge determines the sign of the membrane potential contribution. During an action potential, although the membrane potential changes about 100mV, the concentrations of ions inside and ou
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https://en.wikipedia.org/wiki/Cyrtomium
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Cyrtomium is a genus of about 35 species of ferns in the family Dryopteridaceae, subfamily Dryopteridoideae, according to the Pteridophyte Phylogeny Group classification of 2016 (PPG I). Species are native to Asia, Africa (including Madagascar), and the Pacific Ocean islands (Hawaii). It is very closely related to the genus Polystichum, with 2016 research suggesting it should be included in a clade sister to Polystichum s.s.
Species
, the Checklist of Ferns and Lycophytes of the World accepted the following species:
Cyrtomium aequibasis (C.Chr.) Ching
Cyrtomium anomophyllum (Zenker) Fraser-Jenk.
Cyrtomium atropunctatum Kurata
Cyrtomium caryotideum (Wall. ex Hook. & Grev.) C.Presl
Cyrtomium chingianum P.S.Wang
Cyrtomium confertifolium Ching & K.H.Shing
Cyrtomium conforme Ching
Cyrtomium devexiscapulae (Koidz.) Ching
Cyrtomium elongatum S.K.Wu & P.K.Lôc
Cyrtomium falcatum (L.f.) C.Presl (Japanese holly fern or holly fern)
Cyrtomium fortunei J.Sm.
Cyrtomium grossum Christ
Cyrtomium guizhouense H.S.Kung & P.S.Wang
Cyrtomium hemionitis Christ
Cyrtomium laetevirens (Hiyama) Nakaike
Cyrtomium latifalcatum S.K.Wu & Mitsuta
Cyrtomium lonchitoides (Christ) Christ
Cyrtomium luctuosum J.P.Roux
Cyrtomium macrophyllum (Makino) Tagawa
Cyrtomium membranifolium Ching & K.H.Shing ex H.S.Kung & P.S.Wang
Cyrtomium micropterum (Kunze) Ching
Cyrtomium nephrolepioides (Christ) Copel.
Cyrtomium obliquum Ching & K.H.Shing
Cyrtomium omeiense China & Shing
Cyrtomium pachyphyllum (Rosenst.) C.Chr.
Cy
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https://en.wikipedia.org/wiki/Loop%20inversion
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In computer science, loop inversion is a compiler optimization and loop transformation in which a while loop is replaced by an if block containing a do..while loop. When used correctly, it may improve performance due to instruction pipelining.
Example in C
int i, a[100];
i = 0;
while (i < 100) {
a[i] = 0;
i++;
}
is equivalent to:
int i, a[100];
i = 0;
if (i < 100) {
do {
a[i] = 0;
i++;
} while (i < 100);
}
Despite the seemingly greater complexity of the second example, it may actually run faster on modern CPUs because they use an instruction pipeline. By nature, any jump in the code causes a pipeline stall, which is a detriment to performance.
Additionally, loop inversion allows safe loop-invariant code motion.
Example in three-address code
i := 0
L1: if i >= 100 goto L2
a[i] := 0
i := i + 1
goto L1
L2:
If i had been initialized at 100, the instructions executed at runtime would have been:
if i >= 100
goto L2
Let us assume that i had been initialized to some value less than 100. Now let us look at the instructions executed at the moment after i has been incremented to 99 in the loop:
goto L1
if i < 100
a[i] := 0
i := i + 1
goto L1
if i >= 100
goto L2
<<at L2>>
Now, let's look at the optimized version:
i := 0
if i >= 100 goto L2
L1: a[i] := 0
i := i + 1
if i < 100 goto L1
L2:
Again, let's look at the instructions executed if i is initia
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https://en.wikipedia.org/wiki/QSound
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QSound is the original name for a positional three-dimensional (3D) sound processing algorithm from QSound Labs that creates 3D audio effects from multiple monophonic sources and sums the outputs to two channels for presentation over regular stereo speakers. QSound was eventually re-dubbed "Q1" after the introduction of "Q2", a positional 3D algorithm for headphones. When multi-speaker surround system support was later added to the positional 3D process, the QSound positional 3D audio process became known simply as "Q3D". QSound was founded by Larry Ryckman (CEO), Danny Lowe and John Lees. Jimmy Iovine served as senior vice president of music and Shelly Yakus as vice president of audio engineering in its formative years.
Technology
QSound is essentially a filtering algorithm. It manipulates timing, amplitude, and frequency response to produce a binaural image. Systems like QSound rely on the fact that a sound arriving from one side of the listener will reach one ear before the other and that when it reaches the furthest ear, it is lower in amplitude and spectrally altered due to obstruction by the head. However, the ideal algorithm was arrived at empirically, with parameters adjusted according to the outcomes of many listening tests.
3D positional processing like QSound, the multi-channel QSystem professional processor used in the production of pop music and film audio, is distinct from stereo expansion like QSound QXpander or SRS Sound Retrieval System. Positional 3D aud
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https://en.wikipedia.org/wiki/Derivatization
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Derivatization is a technique used in chemistry which converts a chemical compound into a product (the reaction's derivate) of similar chemical structure, called a derivative.
Generally, a specific functional group of the compound participates in the derivatization reaction and transforms the educt to a derivate of deviating reactivity, solubility, boiling point, melting point, aggregate state, or chemical composition. Resulting new chemical properties can be used for quantification or separation of the educt.
Derivatization techniques are frequently employed in chemical analysis of mixtures and in surface analysis, e.g. in X-ray photoelectron spectroscopy where newly incorporated atoms label characteristic groups.
Derivatization reactions
Several characteristics are desirable for a derivatization reaction:
The reaction is reliable and proceeds to completion. Less unreacted starting material will simplify analysis. Also, this allows a small amount of analyte to be used.
The reaction is general, allowing a wide range of substrates, yet specific to a single functional group, reducing complicating interference.
The products are relatively stable, and form no degradation products within a reasonable period, facilitating analysis.
Some examples of good derivatization reactions are the formation of esters and amides via acyl chlorides.
Classical qualitative organic analysis
Classical qualitative organic analysis usually involves reacting an unknown sample with various reage
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https://en.wikipedia.org/wiki/Hans%20Carl%20Friedrich%20von%20Mangoldt
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Hans Carl Friedrich von Mangoldt (1854 in Weimar– 1925 in Danzig) was a German mathematician who contributed to the solution of the prime number theorem.
Biography
Mangoldt completed his Doctorate of Philosophy (Ph.D) in 1878 at the University of Berlin, where his supervisors were Ernst Kummer and Karl Weierstrass. He contributed to the solution of the prime number theorem by providing rigorous proofs of two statements in Bernhard Riemann's seminal paper "On the Number of Primes Less Than a Given Magnitude". Riemann himself had only given partial proofs of these statements. Mangoldt worked as professor at the RWTH Aachen and was succeeded by Otto Blumenthal.
See also
Prime-counting function
Cartan–Hadamard theorem
Riemann–von Mangoldt formula
Von Mangoldt function
Notes
1854 births
1925 deaths
19th-century German mathematicians
20th-century German mathematicians
Number theorists
Academic staff of RWTH Aachen University
Scientists from Weimar
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https://en.wikipedia.org/wiki/Homoserine
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Homoserine (also called isothreonine) is an α-amino acid with the chemical formula HO2CCH(NH2)CH2CH2OH. L-Homoserine is not one of the common amino acids encoded by DNA. It differs from the proteinogenic amino acid serine by insertion of an additional -CH2- unit into the backbone. Homoserine, or its lactone form, is the product of a cyanogen bromide cleavage of a peptide by degradation of methionine.
Homoserine is an intermediate in the biosynthesis of three essential amino acids: methionine, threonine (an isomer of homoserine), and isoleucine. Its complete biosynthetic pathway includes glycolysis, the tricarboxylic acid (TCA) or citric acid cycle (Krebs cycle), and the aspartate metabolic pathway. It forms by two reductions of aspartic acid via the intermediacy of aspartate semialdehyde. Specifically, the enzyme homoserine dehydrogenase, in association with NADPH, catalyzes a reversible reaction that interconverts L-aspartate-4-semialdehyde to L-homoserine. Then, two other enzymes, homoserine kinase and homoserine O-succinyltransferase use homoserine as a substrate and produce phosphohomoserine and O-succinyl homoserine respectively.
Applications
Commercially, homoserine can serve as precursor to the synthesis of isobutanol and 1,4-butanediol. Purified homoserine is used in enzyme structural studies. Also, homoserine has played important roles in studies to elucidate peptide synthesis and synthesis of proteoglycan glycopeptides. Bacterial cell lines can make copious
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https://en.wikipedia.org/wiki/AP%20site
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In biochemistry and molecular genetics, an AP site (apurinic/apyrimidinic site), also known as an abasic site, is a location in DNA (also in RNA but much less likely) that has neither a purine nor a pyrimidine base, either spontaneously or due to DNA damage. It has been estimated that under physiological conditions 10,000 apurinic sites and 500 apyrimidinic may be generated in a cell daily.
AP sites can be formed by spontaneous depurination, but also occur as intermediates in base excision repair. In this process, a DNA glycosylase recognizes a damaged base and cleaves the N-glycosidic bond to release the base, leaving an AP site. A variety of glycosylases that recognize different types of damage exist, including oxidized or methylated bases, or uracil in DNA. The AP site can then be cleaved by an AP endonuclease, leaving 3'-hydroxyl and deoxyribose-5-phosphate termini (see DNA structure). In alternative fashion, bifunctional glycosylase-lyases can cleave the AP site, leaving a 5' phosphate adjacent to a 3' α,β-unsaturated aldehyde. Both mechanisms form a single-strand break, which is then repaired by either short-patch or long-patch base excision repair.
If left unrepaired, AP sites can lead to mutation during semiconservative replication. They can cause replication fork stalling and are bypassed by translesion synthesis. In E. coli, adenine is preferentially inserted across from AP sites, known as the "A rule". The situation is more complex in higher eukaryotes, with dif
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https://en.wikipedia.org/wiki/Shamus%20%28video%20game%29
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Shamus is a flip-screen shooter with light action-adventure game elements written by Cathryn Mataga (credited as William Mataga) and published by Synapse Software. The original Atari 8-bit family version was released on disk and tape in 1982.
According to Synapse co-founder Ihor Wolosenko, Shamus made the company famous by giving it a reputation for quality.
The game was ported to the Apple II, VIC-20, Commodore 64, TRS-80 Color Computer, TI-99/4A, and IBM PC. Several of these were published by Atarisoft. It was later sold on cartridge by Atari Corporation following the launch of the Atari XEGS in 1987. "Funeral March of a Marionette", the theme song from Alfred Hitchcock Presents, plays on the title screen.
Shamus was followed by a sequel in 1983, Shamus: Case II, with the same characters but different gameplay. In 1999, Mataga released a remake for the Game Boy Color and later both Shamus and Shamus: Case II for iOS.
Gameplay
Inspired by the arcade game Berzerk, the objective of the game is to navigate the eponymous robotic detective through a 4-skill level, 128-room maze of electrified walls. The ultimate goal at the end of this journey is "The Shadow's Lair". Shamus differs from Berzerk in having a persistent world instead of rooms that are randomly generated each time they are entered. There are also items to collect: bottles containing extra lives, mystery question marks, and keys which open exits.
Opposing the player are a number of robotic adversaries, including
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https://en.wikipedia.org/wiki/Haploinsufficiency
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Haploinsufficiency in genetics describes a model of dominant gene action in diploid organisms, in which a single copy of the wild-type allele at a locus in heterozygous combination with a variant allele is insufficient to produce the wild-type phenotype. Haploinsufficiency may arise from a de novo or inherited loss-of-function mutation in the variant allele, such that it yields little or no gene product (often a protein). Although the other, standard allele still produces the standard amount of product, the total product is insufficient to produce the standard phenotype. This heterozygous genotype may result in a non- or sub-standard, deleterious, and (or) disease phenotype. Haploinsufficiency is the standard explanation for dominant deleterious alleles.
In the alternative case of haplosufficiency, the loss-of-function allele behaves as above, but the single standard allele in the heterozygous genotype produces sufficient gene product to produce the same, standard phenotype as seen in the homozygote. Haplosufficiency accounts for the typical dominance of the "standard" allele over variant alleles, where the phenotypic identity of genotypes heterozygous and homozygous for the allele defines it as dominant, versus a variant phenotype produced only by the genotype homozygous for the alternative allele, which defines it as recessive.
Mechanism
The alteration in the gene dosage, which is caused by the loss of a functional allele, is also called allelic insufficiency.
Haploins
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https://en.wikipedia.org/wiki/Derivative%20%28chemistry%29
|
In chemistry, a derivative is a compound that is derived from a similar compound by a chemical reaction.
In the past, derivative also meant a compound that can be imagined to arise from another compound, if one atom or group of atoms is replaced with another atom or group of atoms, but modern chemical language now uses the term structural analog for this meaning, thus eliminating ambiguity. The term "structural analogue" is common in organic chemistry.
In biochemistry, the word is used for compounds that at least theoretically can be formed from the precursor compound.
Chemical derivatives may be used to facilitate analysis. For example, melting point (MP) analysis can assist in identification of many organic compounds. A crystalline derivative may be prepared, such as a semicarbazone or 2,4-dinitrophenylhydrazone (derived from aldehydes or ketones), as a simple way of verifying the identity of the original compound, assuming that a table of derivative MP values is available. Prior to the advent of spectroscopic analysis, such methods were widely used.
In analytical chemistry, derivatization can be used to convert analytes into other species for improving detection. For example, polar groups such as N-H or O-H can be converted into less polar groups. This reaction reduces the boiling point of the molecule, allowing non-volatile compounds to be analyzed by gas chromatography.
See also
Derivatization
Precursor (chemistry)
Product (chemistry)
Structural analog
References
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https://en.wikipedia.org/wiki/D%20battery
|
A D battery (D cell or IEC R20) is a standardized size of a dry cell. A D cell is cylindrical with an electrical contact at each end; the positive end has a nub or bump. D cells are typically used in high current drain applications, such as in large flashlights, radio receivers, and transmitters, and other devices that require an extended running time. A D cell may be either rechargeable or non-rechargeable. Its terminal voltage and capacity depend upon its cell chemistry.
The National Carbon Company introduced the first D cell in 1898. Before smaller cells became more common, D cells were widely known as flashlight batteries. The U.S. military designation for this battery has been BA-30 since sometime before World War II. During World War II, it was designated the Type C battery by the U.S. Navy, leading to confusion with the smaller C cell battery (BA-42).
In 2007, D batteries accounted for 8% of alkaline primary battery sales (numerically) in the US. In 2008, Swiss purchases of D batteries amounted to 3.4% of primary and 1.4% of secondary (rechargeable) sales.
Dimensions and capacity
D batteries have a nominal diameter of 33.2 ± 1 millimeters (1.3 inches).
The overall length is 61.5 millimeters (2.42 inches).
Names
Common
Other
U2 / HP2 / SP2 UK
Type 373 Russia
MN/MX1300
Mono
Goliath
BA-30 US WWII
#1 China
UM 1 JIS
6135-99-464-1938 / 6135-99-109-9428 (NSN)
Flashlight Battery / Torch Battery
B006 (NiMH)
Torcia Italy
Góliátelem Hungary
Pila Grande Arge
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https://en.wikipedia.org/wiki/Tick-borne%20encephalitis%20virus
|
Tick-borne encephalitis virus (TBEV) is a positive-strand RNA virus associated with tick-borne encephalitis in the genus Flavivirus.
Classification
Taxonomy
TBEV is a member of the genus Flavivirus. Other close relatives, members of the TBEV serocomplex, include Omsk hemorrhagic fever virus, Kyasanur Forest disease virus, Alkhurma virus, Louping ill virus and Langat virus.
Subtypes
TBEV has three subtypes:
Western European subtype (formerly Central European encephalitis virus, CEEV; principal tick vector: Ixodes ricinus);
Siberian subtype (formerly West Siberian virus; principal tick vector: Ixodes persulcatus);
Far Eastern subtype (formerly Russian Spring Summer encephalitis virus, RSSEV; principal tick vector: Ixodes persulcatus).
The reference strain is the Sofjin strain.
Virology
Structure
TBEV is a positive-sense single-stranded RNA virus, contained in a 40-60 nm spherical, enveloped capsid. The TBEV genome is approximately 11kb in size, which contains a 5' cap, a single open reading frame with 3' and 5' UTRs, and is without polyadenylation. Like other flaviviruses, the TBEV genome codes for ten viral proteins, three structural, and seven nonstructural (NS).
The structural proteins are C (capsid), PrM (premembrane), which is cleaved to produce the final membrane protein, (M), and envelope protein (E). The seven nonstructural proteins are: NS1, NS2A, NS2B, NS3, NS4A, NS4B, and NS5. The role of some nonstructural proteins is known, NS5 serves as RNA-dependent R
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https://en.wikipedia.org/wiki/EPT
|
EPT may refer to:
Science and technology
Extended Page Table, in Intel x86 microprocessors
Ethanolaminephosphotransferase, an enzyme
Ethylpropyltryptamine, a psychedelic drug
Ephemeroptera, Plecoptera, and Trichoptera, used to test water quality
Other uses
CaMLA English Placement Test, a language proficiency test
Effective performance time, in aviation medicine
Electroputere, a Romanian rolling stock manufacturer
Epsilon Pi Tau, an honor society
European Poker Tour
Estrogen Progestin Therapy, a Hormone replacement therapy
Hellenic Broadcasting Corporation (), the public broadcaster of Greece
Tunisia Polytechnic School (French: )
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https://en.wikipedia.org/wiki/Residual%20entropy
|
Residual entropy is the difference in entropy between a non-equilibrium state and crystal state of a substance close to absolute zero. This term is used in condensed matter physics to describe the entropy at zero kelvin of a glass or plastic crystal referred to the crystal state, whose entropy is zero according to the third law of thermodynamics. It occurs if a material can exist in many different states when cooled. The most common non-equilibrium state is vitreous state, glass.
A common example is the case of carbon monoxide, which has a very small dipole moment. As the carbon monoxide crystal is cooled to absolute zero, few of the carbon monoxide molecules have enough time to align themselves into a perfect crystal (with all of the carbon monoxide molecules oriented in the same direction). Because of this, the crystal is locked into a state with different corresponding microstates, giving a residual entropy of , rather than zero.
Another example is any amorphous solid (glass). These have residual entropy, because the atom-by-atom microscopic structure can be arranged in a huge number of different ways across a macroscopic system.
History
One of the first examples of residual entropy was pointed out by Pauling to describe water ice. In water, each oxygen atom is bonded to two hydrogen atoms. However, when water freezes it forms a tetragonal structure where each oxygen atom has four hydrogen neighbors (due to neighboring water molecules). The hydrogen atoms sitting be
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https://en.wikipedia.org/wiki/Brad%20Anderson%20%28wrestler%29
|
Bradley Anderson (born December 24, 1969) is an American professional wrestler. He is the son of fellow professional wrestler Gene Anderson.
Professional wrestling career
Brad Anderson started wrestling in 1988 after being trained by his father, Gene Anderson, and Nelson Royal. He wrestled in the National Wrestling Alliance's (NWA) Jim Crockett Promotions under his real name as well as the masked 'Zan Panzer' and 'Agent Steele'. In 1990 he wrestled in the Pacific Northwest Territory and formed a tag team with Ricky Santana that won the PNW tag team titles. In 1991 he went to Puerto Rico's World Wrestling Council and feuded with Santana over the WWC Light Heavyweight Title. Brad Anderson worked in the NAWA/SAPW as The Viper. He was unmasked by "War Eagle" Chris Chavis. In 1998, he was part of a tag team called "Triple X" in NWA Mid-Atlantic with Drake Dawson and manager Strawberry Fields Winning the NWA North Continental Tag Team Titles in 1999 from The Border Patrol.
In May 2019, Anderson was involved in an incident in North Carolina promotion Revolution Wrestling Authority in which he legitimately attacked another wrestler named Jacob Ryan during a match. The assault was broken up by promoter Julian Strauss and many of the other wrestlers who were booked for the event, and Anderson was escorted from the building. Anderson later defended himself by claiming that Ryan had injured his son Carter with a sloppy clothesline in a segment on the previous event, and that he handle
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https://en.wikipedia.org/wiki/Morphant
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An organism which has been treated with a morpholino antisense oligo to temporarily knock down expression of a targeted gene is called a morphant.
Background
This term was coined by Prof. Steve Ekker to describe the zebrafish with which he was experimenting; by knocking down embryonic gene expression using Morpholinos, Prof. Ekker "phenocopied" known zebrafish mutations, that is, he raised embryos that had the same morphological phenotype as embryonic zebrafish with specific gene mutations. Prof. Ekker's papers and presentations describing morphant phenocopies of mutant phenotypes, in combination with Prof. Janet Heasman's earlier work with Morpholinos in Xenopus embryos, led to rapid adoption of Morpholino technology by the developmental biology community.
References
Molecular genetics
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https://en.wikipedia.org/wiki/Isoflavone
|
Isoflavones are substituted derivatives of isoflavone, a type of naturally occurring isoflavonoids, many of which act as phytoestrogens in mammals. Isoflavones are produced almost exclusively by the members of the bean family, Fabaceae (Leguminosae).
Although isoflavones and closely related phytoestrogens are sold as dietary supplements, there is little scientific evidence for either the safety of long-term supplementation or of health benefits from these compounds. Some studies have identified potential risks from high intake of isoflavones, such as in women with a history of breast cancer, but this concern has not been substantiated with high-quality clinical research.
Organic chemistry and biosynthesis
Isoflavone is an isomer of flavone, which is chromone substituted with a phenyl group in the 2-position. In isoflavone, the phenyl group is in the 3-position.
Substituted isoflavone derivatives are related to the parent by the replacement of two or three hydrogen atoms with hydroxyl groups.
Isoflavone differs from flavone (2-phenyl-4H-1-benzopyr-4-one) in location of the phenyl group.
Isoflavones are produced via a branch of the general phenylpropanoid pathway that produces flavonoid compounds in higher plants. Soybeans are the most common source of isoflavones in human food; the major isoflavones in soybean are genistein and daidzein. The phenylpropanoid pathway begins from the amino acid phenylalanine, and an intermediate of the pathway, naringenin, is sequentially
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https://en.wikipedia.org/wiki/Dye-sensitized%20solar%20cell
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A dye-sensitized solar cell (DSSC, DSC, DYSC or Grätzel cell) is a low-cost solar cell belonging to the group of thin film solar cells. It is based on a semiconductor formed between a photo-sensitized anode and an electrolyte, a photoelectrochemical system. The modern version of a dye solar cell, also known as the Grätzel cell, was originally co-invented in 1988 by Brian O'Regan and Michael Grätzel at UC Berkeley and this work was later developed by the aforementioned scientists at the École Polytechnique Fédérale de Lausanne (EPFL) until the publication of the first high efficiency DSSC in 1991. Michael Grätzel has been awarded the 2010 Millennium Technology Prize for this invention.
The DSSC has a number of attractive features; it is simple to make using conventional roll-printing techniques, is semi-flexible and semi-transparent which offers a variety of uses not applicable to glass-based systems, and most of the materials used are low-cost. In practice it has proven difficult to eliminate a number of expensive materials, notably platinum and ruthenium, and the liquid electrolyte presents a serious challenge to making a cell suitable for use in all weather. Although its conversion efficiency is less than the best thin-film cells, in theory its price/performance ratio should be good enough to allow them to compete with fossil fuel electrical generation by achieving grid parity. Commercial applications, which were held up due to chemical stability problems, had been forecas
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https://en.wikipedia.org/wiki/Glutenin
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Glutenin (a type of glutelin) is a major protein within wheat flour, making up 47% of the total protein content. The glutenins are protein aggregates of high-molecular-mass (HMW) and low-molecular-mass (LMW) subunits with molar masses from about 200,000 to a few million, which are stabilized by intermolecular disulfide bonds, hydrophobic interactions and other forces. Glutenin is responsible for the strength and elasticity of dough.
Wheat gluten proteins consist of two major fractions: the gliadins and the glutenins. Gliadins are monomeric proteins, which can be separated into four groups: alpha-, beta-, gamma- and omega-gliadins. They are structurally similar to LMW glutenins. Glutenins occur as multimeric aggregates of high-molecular-mass and low-molecular-mass subunits held together by disulfide bonds. The way the glutenins form their disulfide bond network is predicted to be regulated by the hydrophobicity in the peptide sections where their cysteins are located, explaining why the gliadins are monomeric despite sharing similar conserved cysteine motifs as the LMW-glutenins.
Breadmaking qualities are largely dependent on the number and composition of HMW glutenin subunits. It has been demonstrated that alleles Glu-A1b (Ax2∗) and Glu-D1d (Dx5 + Dy10) are normally associated with superior end-use quality, especially dough strength.
References
External links
family:"gliadin glutenin family" - UniProt query
Gluten
Glycoproteins
Seed storage proteins
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https://en.wikipedia.org/wiki/2600%20hertz
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2600 hertz (2600 Hz) is a frequency in hertz (cycles per second) that was used in telecommunication signaling in mid-20th century long-distance telephone networks using carrier systems.
Tone signaling carrier systems operated in the standard telephony voice frequency range ( to ). They replaced direct current (D.C.) signaling on toll trunk lines because they could be used with any type of toll facility over any length of transmission line that was suitable for voice transmissions. This included transmission through line repeaters and other facilities that would distort, block, or otherwise prohibit D.C. loop-disconnect signaling, such as rotary dial pulses, and on-hook/off-hook signaling. Common frequencies for this purpose were , , , , and , the latter being just outside the voice range. These signaling systems were continuous tone methods, so that the idle condition of a trunk line could easily be detected by the presence of the appropriate signaling frequency, in contrast to conditions of a quiet line which could be due to pauses in speech, or arise from line faults. The tones were typically transmitted in the same physical and logical channel, which characterizes these systems as in-band signaling methods, which do not require additional bandwidth for control of the network and benefit from a single amplification facility for speech and signaling.
The most common single-frequency signaling (SF) system in use in the United States from the 1950s to the 1970s used the freq
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