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https://en.wikipedia.org/wiki/Medicus%20curat%2C%20natura%20sanat | is an old aphorism in Latin which means that the physician cures while nature heals.
Variations in Latin include natura sanat, medicus curat morbus and there are equivalents in other languages such as Benjamin Franklin's sarcastic "God heals, and the Doctor takes the Fees" and Ambroise Paré's "Je le pansai, Dieu le guérit." The phrase was used in medieval times and the idea has been traced back to classical authors such as Galen and Aristotle.
Georg Groddeck made an acronym of the phrase which he used as the title of his 1913 book, Nasamecu.
See also
Nature cure (disambiguation)
Nature therapy
Naturopathy
Vis medicatrix naturae |
https://en.wikipedia.org/wiki/Improved-definition%20television | Improved-definition television (IDTV) or enhanced-quality television transmitters and receivers exceed the performance requirements of the NTSC standard, while remaining within the general parameters of NTSC emissions standards.
IDTV improvements may be made at the television transmitter or receiver. Improvements include enhancements in encoding, digital filtering, scan interpolation, interlaced line scanning, and ghost cancellation.
IDTV improvements must allow the TV signal to be transmitted and received in the standard 4:3 aspect ratio.
See also
Comb filter
Federal Standard 1037C
Video scaler |
https://en.wikipedia.org/wiki/David%20Thissen | David Michael Thissen (born c. 1950) is an emeritus professor of quantitative psychology at the University of North Carolina and former President of the Psychometric Society. He is a fellow at the American Statistical Association and the American Psychological Society. He is known for his contributions to item response theory.
Early life and education
The eldest of five children, Thissen graduated from St. Edmond High School in Fort Dodge, Iowa and was a national semifinalist in the 1967 Westinghouse Science Talent Search. He earned a bachelor's degree from Saint Louis University and a PhD in quantitative psychology from the University of Chicago, where he was awarded an NSF Graduate Research Fellowship.
Career
Upon receiving his PhD in 1976, Thissen joined the psychology faculty at the University of Kansas and was appointed an associate professor (with tenure) five years later. He moved to the University of North Carolina at Chapel Hill in 1990 as a full professor of psychology and served as the chair of the L. L. Thurstone Psychometric Laboratory until 2002. He continues to serve UNC as a full professor in the Department of Psychology and Neuroscience.
He is the author of hundreds of publications on testing and measurement, patient-reported health outcomes (PROs), human development, and statistical graphics. He published Test Scoring with Howard Wainer in 2001.
He has also developed numerous psychometric software programs including Multilog and IRTPRO.
Selected publications |
https://en.wikipedia.org/wiki/Green%27s%20function%20%28many-body%20theory%29 | In many-body theory, the term Green's function (or Green function) is sometimes used interchangeably with correlation function, but refers specifically to correlators of field operators or creation and annihilation operators.
The name comes from the Green's functions used to solve inhomogeneous differential equations, to which they are loosely related. (Specifically, only two-point 'Green's functions' in the case of a non-interacting system are Green's functions in the mathematical sense; the linear operator that they invert is the Hamiltonian operator, which in the non-interacting case is quadratic in the fields.)
Spatially uniform case
Basic definitions
We consider a many-body theory with field operator (annihilation operator written in the position basis) .
The Heisenberg operators can be written in terms of Schrödinger operators as
and the creation operator is , where is the grand-canonical Hamiltonian.
Similarly, for the imaginary-time operators,
[Note that the imaginary-time creation operator is not the Hermitian conjugate of the annihilation operator .]
In real time, the -point Green function is defined by
where we have used a condensed notation in which signifies and signifies . The operator denotes time ordering, and indicates that the field operators that follow it are to be ordered so that their time arguments increase from right to left.
In imaginary time, the corresponding definition is
where signifies . (The imaginary-time variables are restricted to the range from to the inverse temperature .)
Note regarding signs and normalization used in these definitions: The signs of the Green functions have been chosen so that Fourier transform of the two-point () thermal Green function for a free particle is
and the retarded Green function is
where is the Matsubara frequency.
Throughout, is for bosons and for fermions and denotes either a commutator or anticommutator as appropriate.
(See below for details.)
Two-point functions
The |
https://en.wikipedia.org/wiki/Urine%20deflector | A urine deflector is a device for deflecting the stream of urine during urination. These may be part of a chamber pot, latrine or toilet intended for the purpose, or they may be deterrents, installed in the sides or corners of buildings to discourage their casual use as urinals by passers-by. They may be constructed in various ways from a variety of materials but are typically designed to have an angled surface which catches and redirects the stream.
Intentional design
Equipment used for toilet training such as a potty chair will typically include a urine deflector to ensure that the urine does not splash forward and outside the receptacle.
Latrines constructed by the US Marines would contain urine deflectors made from sheet metal or tar paper. These would catch and direct the urine into a trough which would carry it to a separate drainage pit. This would minimise the unpleasant smell which typically results from decomposition and production of ammonia. Other designs of latrine typically include similar urine deflectors to prevent degradation of the wooden components and the walls of the pit.
Deterrent
Such devices were common in the streets of London in the 19th century. A correspondent to The Farmer's Magazine wrote in 1809, Some may still be found in places such as the Bank of England, Fleet Street and the Savoy. Other cities where antique examples may still be seen include Lviv, Norwich and Venice. In other cities such as Vienna, barriers such as iron railings and spikes have been used to keep people away from attractive corners and crannies.
German cities such as Hamburg and Cologne have pioneered the use of hydrophobic paint on walls to deter Wildpinklers. This water-repellent coating causes the stream to rebound at a similar angle and so wet the offender. Other places such as Hackney, Manchester and San Francisco have since evaluated the method for particular trouble spots. London's Soho district was painted in this way in 2022 and Westminst |
https://en.wikipedia.org/wiki/Unsharp%20masking | Unsharp masking (USM) is an image sharpening technique, first implemented in darkroom photography, but now commonly used in digital image processing software. Its name derives from the fact that the technique uses a blurred, or "unsharp", negative image to create a mask of the original image. The unsharp mask is then combined with the original positive image, creating an image that is less blurry than the original. The resulting image, although clearer, may be a less accurate representation of the image's subject.
In the context of signal processing, an unsharp mask is generally a linear or nonlinear filter that amplifies the high-frequency components of a signal.
Photographic darkroom unsharp masking
For the photographic darkroom process, a large-format glass plate negative is contact-copied onto a low-contrast film or plate to create a positive image. However, the positive copy is made with the copy material in contact with the back of the original, rather than emulsion-to-emulsion, so it is blurred. After processing this blurred positive is replaced in contact with the back of the original negative. When light is passed through both negative and in-register positive (in an enlarger, for example), the positive partially cancels some of the information in the negative.
Because the positive has been blurred intentionally, only the low-frequency (blurred) information is cancelled. In addition, the mask effectively reduces the dynamic range of the original negative. Thus, if the resulting enlarged image is recorded on contrasty photographic paper, the partial cancellation emphasizes the high-spatial-frequency information (fine detail) in the original, without loss of highlight or shadow detail. The resulting print appears more acute than one made without the unsharp mask: its acutance is increased.
In the photographic procedure, the amount of blurring can be controlled by changing the "softness" or "hardness" (from point source to fully diffuse) of the light so |
https://en.wikipedia.org/wiki/Kinetic%20capillary%20electrophoresis | Kinetic capillary electrophoresis or KCE is capillary electrophoresis of molecules that interact during electrophoresis.
KCE was introduced and developed by Professor Sergey Krylov and his research group at York University, Toronto, Canada. It serves as a conceptual platform for development of homogeneous chemical affinity methods for studies of molecular interactions (measurements of binding and rate constants) and affinity purification (purification of known molecules and search for unknown molecules). Different KCE methods are designed by varying initial and boundary conditions – the way interacting molecules enter and exit the capillary. Several KCE methods were described: non-equilibrium capillary electrophoresis of the equilibrium mixtures (NECEEM), sweeping capillary electrophoresis (SweepCE), and plug-plug KCE (ppKCE).
External links
More detailed description and several applications of KCE methods (measuring equilibrium and rate constants of molecular interactions, quantitative affinity analysis of proteins, thermochemistry of protein–ligand interactions, selection of aptamers, determination of temperature inside a capillary) can be found in a PDF presentation: KCE is a conceptual platform for kinetic homogeneous affinity methods. |
https://en.wikipedia.org/wiki/Partial%20inverse%20of%20a%20matrix | In linear algebra and statistics, the partial inverse of a matrix is an operation related to Gaussian elimination which has applications in numerical analysis and statistics. It is also known by various authors as the principal pivot transform, or as the sweep, gyration, or exchange operator.
Given an matrix over a vector space partitioned into blocks:
If is invertible, then the partial inverse of around the pivot block is created by inverting , putting the Schur complement in place of , and adjusting the off-diagonal elements accordingly:
Conceptually, partial inversion corresponds to a rotation of the graph of the matrix , such that, for conformally-partitioned column matrices and :
As defined this way, this operator is its own inverse: , and if the pivot block is chosen to be the entire matrix, then the transform simply gives the matrix inverse . Note that some authors define a related operation (under one of the other names) which is not an inverse per se; particularly, one common definition instead has .
The transform is often presented as a pivot around a single non-zero element , in which case one has
Partial inverses obey a number of nice properties:
inversions around different blocks commute, so larger pivots may be built up from sequences of smaller ones
partial inversion preserves the space of symmetric matrices
Use of the partial inverse in numerical analysis is due to the fact that there is some flexibility in the choices of pivots, allowing for non-invertible elements to be avoided, and because the operation of rotation (of the graph of the pivoted matrix) has better numerical stability than the shearing operation which is implicitly performed by Gaussian elimination. Use in statistics is due to the fact that the resulting matrix nicely decomposes into blocks which have useful meanings in the context of linear regression. |
https://en.wikipedia.org/wiki/Emojipedia | Emojipedia is an emoji reference website which documents the meaning and common usage of emoji characters in the Unicode Standard. Most commonly described as an emoji encyclopedia or emoji dictionary, Emojipedia also publishes articles and provides tools for tracking new emoji characters, design changes and usage trends. It has been owned by Zedge since 2021.
Emojipedia is a non-voting associate member of The Unicode Consortium.
History
Jeremy Burge created Emojipedia in 2013, and told the Hackney Gazette "the idea came about when Apple added emojis to iOS 6, but failed to mention which ones were new".
Emojipedia rose to prominence with the release of Unicode 7 in 2014, when The Register reported the "online encyclopedia of emojis has been chucked offline after vast numbers of people visited the site" in relation to the downtime experienced by the site at the time.
In 2015, Emojipedia entered its first partnership with Quartz to release an app that allowed users access previously-hidden country flag emojis on iOS.
Emojipedia told Business Insider in early 2016 that it served "over 140 million page views" per year, and was profitable. In mid-2016, Emojipedia "urged Apple to rethink its plan to convert the handgun emoji symbol into a water pistol icon" citing cross-platform confusion.
In 2017, The Library of Congress launched the Web Cultures Web Archive which featured a history of memes, gifs, and emojis from references including Emojipedia, Boing Boing and GIPHY.
The Sydney Morning Herald reported that the site served 23 million page views in October 2017. Total page views for 2013–2019 were said to have reached one billion by February 2019. The New Yorker reported Emojipedia served 50 million page views in April 2020.
In August 2021, Emojipedia was acquired by Zedge for an undisclosed amount.
In February 2022, Keith Broni became Emojipedia's editor-in-chief, taking over from founder and chief emoji officer Jeremy Burge.
In July 2022, Emojipedia added mul |
https://en.wikipedia.org/wiki/Stein%E2%80%93Str%C3%B6mberg%20theorem | In mathematics, the Stein–Strömberg theorem or Stein–Strömberg inequality is a result in measure theory concerning the Hardy–Littlewood maximal operator. The result is foundational in the study of the problem of differentiation of integrals. The result is named after the mathematicians Elias M. Stein and Jan-Olov Strömberg.
Statement of the theorem
Let λn denote n-dimensional Lebesgue measure on n-dimensional Euclidean space Rn and let M denote the Hardy–Littlewood maximal operator: for a function f : Rn → R, Mf : Rn → R is defined by
where Br(x) denotes the open ball of radius r with center x. Then, for each p > 1, there is a constant Cp > 0 such that, for all natural numbers n and functions f ∈ Lp(Rn; R),
In general, a maximal operator M is said to be of strong type (p, p) if
for all f ∈ Lp(Rn; R). Thus, the Stein–Strömberg theorem is the statement that the Hardy–Littlewood maximal operator is of strong type (p, p) uniformly with respect to the dimension n. |
https://en.wikipedia.org/wiki/Genetic%20divergence | Genetic divergence is the process in which two or more populations of an ancestral species accumulate independent genetic changes (mutations) through time, often leading to reproductive isolation and continued mutation even after the populations have become reproductively isolated for some period of time, as there isn’t genetic exchange anymore. In some cases, subpopulations cover living in ecologically distinct peripheral environments can exhibit genetic divergence from the remainder of a population, especially where the range of a population is very large (see parapatric speciation). The genetic differences among divergent populations can involve silent mutations (that have no effect on the phenotype) or give rise to significant morphological and/or physiological changes. Genetic divergence will always accompany reproductive isolation, either due to novel adaptations via selection and/or due to genetic drift, and is the principal mechanism underlying speciation.
On a molecular genetics level, genetic divergence is due to changes in a small number of genes in a species, resulting in speciation. However, researchers argue that it is unlikely that divergence is a result of a significant, single, dominant mutation in a genetic locus because if that were so, the individual with that mutation would have zero fitness. Consequently, they could not reproduce and pass the mutation on to further generations. Hence, it is more likely that divergence, and subsequently reproductive isolation, are the outcomes of multiple small mutations over evolutionary time accumulating in a population isolated from gene flow.
Causes
Founder effect
One possible cause of genetic divergence is the founder effect, which is when a few individuals become isolated from their original population. Those individuals might overrepresent a certain genetic pattern, which means that certain biological characteristics are overrepresented. These individuals can form a new population with different gene |
https://en.wikipedia.org/wiki/Bat%20SARS-like%20coronavirus%20WIV1 | Bat SARS-like coronavirus WIV1 (Bat SL-CoV-WIV1), also sometimes called SARS-like coronavirus WIV1, is a strain of severe acute respiratory syndrome–related coronavirus (SARSr-CoV) isolated from Chinese rufous horseshoe bats in 2013 (Rhinolophus sinicus). Like all coronaviruses, virions consist of single-stranded positive-sense RNA enclosed within an envelope.
Zoonosis
The discovery confirms that bats are the natural reservoir of SARS-CoV. Phylogenetic analysis shows the possibility of direct transmission of SARS from bats to humans without the intermediary Chinese civets, as previously believed.
Phylogenetic
See also
Bat as food
Bat coronavirus RaTG13
Bat virome
SARS-CoV-2
Wuhan Institute of Virology (WIV) |
https://en.wikipedia.org/wiki/Myticin | Myticin is a cysteine-rich peptide produced in three isoforms, A, B and C, by Mytilus galloprovincialis (Mediterranean mussel), which are found primarily in marine habitats. Myticin is also produced in other species of Mytilus (Mytilus spp.), though the properties of Myticin in Mytilus galloprovincialis is understood to a greater extent. Isoforms A and B show antibacterial activity against Gram-positive bacteria, while isoform C is additionally active against the fungus Fusarium oxysporum and bacterium Escherichia coli (streptomycin resistant strain D31). Myticin-prepro is the precursor peptide.
The mature molecule, named myticin, consists of 40 residues, with four intramolecular disulphide bridges, an N-terminal signal peptide and a cysteine array in the primary structure different from that of previously characterised cysteine-rich antimicrobial peptides. The first 20 amino acids are a putative signal peptide, and the antimicrobial peptide sequence is a 36-residue C-terminal extension. Such a structure suggests that myticins are synthesised as prepro-proteins that are then processed by various proteolytic events before storage in the hemocytes as the active peptide. Myticin precursors are expressed mainly in the haemocytes.
Role of Myticin in Mytilus galloprovincialis
AMPs (Antimicrobial peptides) play a significant role in innate immunity defenses exhibited by Bivalves. In marine organisms, AMPs are the main factor in innate immune response which helps to protect them against pathogenic microorganisms in their environment. The innate immune response is thought be nonspecific, though there is limited research in this area. It is unclear whether invertebrates such as bivalves have a similar immune system to vertebrates, however, Myticin is expressed in the hemocytes of mussels, and recent studies have suggested that this molecule is activated after injury to its tissues.
Isoform C
Isoform C is the most widely studied isoform of myticin, most likely due to its |
https://en.wikipedia.org/wiki/Slipped%20strand%20mispairing | Slipped strand mispairing (SSM, also known as replication slippage) is a mutation process which occurs during DNA replication. It involves denaturation and displacement of the DNA strands, resulting in mispairing of the complementary bases. Slipped strand mispairing is one explanation for the origin and evolution of repetitive DNA sequences.
It is a form of mutation that leads to either a trinucleotide or dinucleotide expansion, or sometimes contraction, during DNA replication. A slippage event normally occurs when a sequence of repetitive nucleotides (tandem repeats) are found at the site of replication. Tandem repeats are unstable regions of the genome where frequent insertions and deletions of nucleotides can take place, resulting in genome rearrangements. DNA polymerase, the main enzyme to catalyze the polymerization of free deoxyribonucleotides into a newly forming DNA strand, plays a significant role in the occurrence of this mutation. When DNA polymerase encounters a direct repeat, it can undergo a replication slippage.
Strand slippage may also occur during the DNA synthesis step of DNA repair processes. Within DNA trinucleotide repeat sequences, the repair of DNA damage by the processes of homologous recombination, non-homologous end joining, DNA mismatch repair or base excision repair may involve strand slippage mispairing leading to trinucleotide repeat expansion when the repair is completed.
Slipped strand mispairing has also been shown to function as a phase variation mechanism in certain bacteria.
Stages
Slippage occurs through five main stages:
In the first step, DNA polymerase encounters the direct repeat during the replication process.
The polymerase complex suspends replication and is temporarily released from the template strand.
The newly synthesized strand then detaches from the template strand and pairs with another direct repeat upstream.
DNA polymerase reassembles its position on the template strand and resumes normal replication, |
https://en.wikipedia.org/wiki/%282%2B1%29-dimensional%20topological%20gravity | In two spatial and one time dimensions, general relativity turns out to have no propagating gravitational degrees of freedom. In fact, it can be shown that in a vacuum, spacetime will always be locally flat (or de Sitter or anti-de Sitter depending upon the cosmological constant). This makes (2+1)-dimensional topological gravity (2+1D topological gravity) a topological theory with no gravitational local degrees of freedom.
Physicists became interested in the relation between Chern–Simons theory and gravity during the 1980s.
During this period, Edward Witten argued that 2+1D topological gravity is equivalent to a Chern–Simons theory with the gauge group for a negative cosmological constant, and for a positive one. This theory can be exactly solved, making it a toy model for quantum gravity. The Killing form involves the Hodge dual.
Witten later changed his mind, and argued that nonperturbatively 2+1D topological gravity differs from Chern–Simons because the functional measure is only over nonsingular vielbeins. He suggested the CFT dual is a monster conformal field theory, and computed the entropy of BTZ black holes. |
https://en.wikipedia.org/wiki/49th%20meridian%20east | The meridian 49° east of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, Europe, Asia, Africa, the Indian Ocean, Madagascar, the Southern Ocean, and Antarctica to the South Pole.
The 49th meridian east forms a great circle with the 131st meridian west.
From Pole to Pole
Starting at the North Pole and heading south to the South Pole, the 49th meridian east passes through:
{| class="wikitable plainrowheaders"
! scope="col" width="115" | Co-ordinates
! scope="col" | Country, territory or sea
! scope="col" | Notes
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Arctic Ocean
| style="background:#b0e0e6;" |
|-
|
! scope="row" |
| Island of Zemlya Georga, Franz Josef Land
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Barents Sea
| style="background:#b0e0e6;" | Nightingale Channel
|-
|
! scope="row" |
| Island of Zemlya Georga, Franz Josef Land
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Barents Sea
| style="background:#b0e0e6;" |
|-
|
! scope="row" |
| Kolguyev island
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Barents Sea
| style="background:#b0e0e6;" |
|-
|
! scope="row" |
| Passing just west of Kazan
|-
|
! scope="row" |
|
|-
|
! scope="row" |
|
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Caspian Sea
| style="background:#b0e0e6;" |
|-
|
! scope="row" |
|
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Caspian Sea
| style="background:#b0e0e6;" |
|-
|
! scope="row" |
|
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Persian Gulf
| style="background:#b0e0e6;" |
|-
|
! scope="row" |
|
|-
|
! scope="row" |
|
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Indian Ocean
| style="background:#b0e0e6;" | Gulf of Aden
|-
|
! scope="row" |
|
|-
| sty |
https://en.wikipedia.org/wiki/Accelerometer | An accelerometer is a tool that measures proper acceleration. Proper acceleration is the acceleration (the rate of change of velocity) of a body in its own instantaneous rest frame; this is different from coordinate acceleration, which is acceleration in a fixed coordinate system. For example, an accelerometer at rest on the surface of the Earth will measure an acceleration due to Earth's gravity, straight upwards (by definition) of g ≈ 9.81 m/s2. By contrast, accelerometers in free fall (falling toward the center of the Earth at a rate of about 9.81 m/s2) will measure zero.
Accelerometers have many uses in industry and science. Highly sensitive accelerometers are used in inertial navigation systems for aircraft and missiles. Vibration in rotating machines is monitored by accelerometers. They are used in tablet computers and digital cameras so that images on screens are always displayed upright. In unmanned aerial vehicles, accelerometers help to stabilise flight.
When two or more accelerometers are coordinated with one another, they can measure differences in proper acceleration, particularly gravity, over their separation in space—that is, the gradient of the gravitational field. Gravity gradiometry is useful because absolute gravity is a weak effect and depends on the local density of the Earth, which is quite variable.
Single- and multi-axis accelerometers can detect both the magnitude and the direction of the proper acceleration, as a vector quantity, and can be used to sense orientation (because the direction of weight changes), coordinate acceleration, vibration, shock, and falling in a resistive medium (a case in which the proper acceleration changes, increasing from zero). Micromachined microelectromechanical systems (MEMS) accelerometers are increasingly present in portable electronic devices and video-game controllers, to detect changes in the positions of these devices.
Physical principles
An accelerometer measures proper acceleration, which is the |
https://en.wikipedia.org/wiki/Munin%20%28satellite%29 | Munin was a Swedish nanosatellite. It was launched on November 21, 2000 on a Delta II rocket from the Vandenberg Air Force Base in California, together with two other satellites. Munin was developed by the Swedish Institute of Space Physics in cooperation with students from Luleå University of Technology and Umeå University. Last contact was on February 12, 2001, after a manual CPU reset; failure was probably in the boot PROM.
General information
Dimensions
Size: 213 x 213 x 218 (height) mm
Mass:
Science
Combined ion and electron spectrometer
High energy particle detector
Miniature CCD camera intended for auroral imaging
Onboard computer
CPU: Texas Instrument TMS320C50 at
RAM: 2 MByte
Elliptical polar orbit. Perigee: 698 km, apogee: 1800 km.
See also
Swedish National Space Board |
https://en.wikipedia.org/wiki/IBM%20Advanced%20Peer-to-Peer%20Networking | IBM Advanced Peer-to-Peer Networking (APPN) is an extension to the Systems Network Architecture (SNA) "that allows large and small computers to communicate as peers across local and wide-area networks."
Goals and features
The goals of APPN were:
Provide effective routing for SNA traffic
Allow sessions to be established without the involvement of a central computer
Reduce the requirements to predict resource use
Provide prioritization within SNA traffic
Support both legacy and APPN traffic
To meet these goals it includes features such as these:
distributed network control
dynamic exchange of network topology information to foster ease of connection, reconfiguration, and route selection
dynamic definition of network resources
automated resource registration and directory lookup.
History
APPN was defined around 1986, and was meant to complement IBM's Systems Network Architecture. It was designed as a simplification, but it turned out to be significantly complex, in particular in migration situations.
APPN was originally meant to be a "DECNET killer", but DEC actually died before APPN was completed. APPN has been largely superseded by TCP/IP (Internet).
APPN evolved to include a more efficient data routing layer which was called High Performance Routing (HPR). HPR was made available across a range of enterprise corporation networking products in the late 1990s, but today is typically used only within IBM's z/OS environments as a replacement for legacy SNA networks. It seems to be still widely used within UDP tunnels, this technology is known as Enterprise Extender.
APPN should not be confused with the similarly named APPC (Advanced Program-to-Program Communication). APPN manages communication between machines, including routing, and operates at the transport and network layers. By contrast, APPC manages communication between programs, operating at the application and presentation layers.
APPN has nothing to do with peer-to-peer file sharing software such |
https://en.wikipedia.org/wiki/Transistor%20model | Transistors are simple devices with complicated behavior. In order to ensure the reliable operation of circuits employing transistors, it is necessary to scientifically model the physical phenomena observed in their operation using transistor models. There exists a variety of different models that range in complexity and in purpose. Transistor models divide into two major groups: models for device design and models for circuit design.
Models for device design
The modern transistor has an internal structure that exploits complex physical mechanisms. Device design requires a detailed understanding of how device manufacturing processes such as ion implantation, impurity diffusion, oxide growth, annealing, and etching affect device behavior. Process models simulate the manufacturing steps and provide a microscopic description of device "geometry" to the device simulator. "Geometry" does not mean readily identified geometrical features such as a planar or wrap-around gate structure, or raised or recessed forms of source and drain (see Figure 1 for a memory device with some unusual modeling challenges related to charging the floating gate by an avalanche process). It also refers to details inside the structure, such as the doping profiles after completion of device processing.
With this information about what the device looks like, the device simulator models the physical processes taking place in the device to determine its electrical behavior in a variety of circumstances: DC current–voltage behavior, transient behavior (both large-signal and small-signal), dependence on device layout (long and narrow versus short and wide, or interdigitated versus rectangular, or isolated versus proximate to other devices). These simulations tell the device designer whether the device process will produce devices with the electrical behavior needed by the circuit designer, and is used to inform the process designer about any necessary process improvements. Once the process gets close |
https://en.wikipedia.org/wiki/Doubling%20the%20cube | Doubling the cube, also known as the Delian problem, is an ancient geometric problem. Given the edge of a cube, the problem requires the construction of the edge of a second cube whose volume is double that of the first. As with the related problems of squaring the circle and trisecting the angle, doubling the cube is now known to be impossible to construct by using only a compass and straightedge, but even in ancient times solutions were known that employed other tools.
The Egyptians, Indians, and particularly the Greeks were aware of the problem and made many futile attempts at solving what they saw as an obstinate but soluble problem. However, the nonexistence of a compass-and-straightedge solution was finally proven by Pierre Wantzel in 1837.
In algebraic terms, doubling a unit cube requires the construction of a line segment of length , where ; in other words, , the cube root of two. This is because a cube of side length 1 has a volume of , and a cube of twice that volume (a volume of 2) has a side length of the cube root of 2. The impossibility of doubling the cube is therefore equivalent to the statement that is not a constructible number. This is a consequence of the fact that the coordinates of a new point constructed by a compass and straightedge are roots of polynomials over the field generated by the coordinates of previous points, of no greater degree than a quadratic. This implies that the degree of the field extension generated by a constructible point must be a power of 2. The field extension generated by , however, is of degree 3.
Proof of impossibility
We begin with the unit line segment defined by points (0,0) and (1,0) in the plane. We are required to construct a line segment defined by two points separated by a distance of . It is easily shown that compass and straightedge constructions would allow such a line segment to be freely moved to touch the origin, parallel with the unit line segment - so equivalently we may consider the task of con |
https://en.wikipedia.org/wiki/Baker%20clamp | Baker clamp is a generic name for a class of electronic circuits that reduce the storage time of a switching bipolar junction transistor (BJT) by applying a nonlinear negative feedback through various kinds of diodes. The reason for slow turn-off times of saturated BJTs is the stored charge in the base. It must be removed before the transistor will turn off since the storage time is a limiting factor of using bipolar transistors and IGBTs in fast switching applications. The diode-based Baker clamps prevent the transistor from saturating and thereby accumulating a lot of stored charge.
Origin
The Baker clamp is named after Richard H. Baker, who described it in his 1956 technical report "Maximum Efficiency Transistor Switching Circuits". Baker called the technique "back clamping", but the circuit is now called a Baker clamp. Many sources credit Baker's report for the two-diode clamp circuit.
Also in 1956, Baker described the circuit in a patent application; the 1961 issued patent US 3,010,031 claims the use of the clamp in symmetrical flip-flop circuits.
Similar clamp circuits are said to have been known before Baker's report. Kyttälä states: "Although invention of the Baker clamp circuit is credited to Richard H. Baker (US Patent 3,010,031) it was already common knowledge in 1953 and described in transistor introductory papers that were written by Richard F. Shea." However, Shea's 1953 transistor text does not describe a similar clamp circuit. Shea's 1957 text does describe the clamp circuit and references Baker's technical report.
There are other clamp circuits. A 1959 manual describes a technique called "saturation clamping". In that scheme, there is a saturation clamp supply at about 2 volts connected to the collector with a saturation clamp diode. When the transistor nears saturation, the clamp diode turns on and supplies the extra collector current to keep the transistor from saturating. The saturation clamp supply needs to supply substantial current |
https://en.wikipedia.org/wiki/KCNIP4 | Kv channel-interacting protein 4 is a protein that in humans is encoded by the KCNIP4 gene.
This gene encodes a member of the family of voltage-gated potassium (Kv) channel-interacting proteins (KCNIPs), which belong to the recoverin branch of the EF-hand superfamily. Members of the KCNIP family are small calcium binding proteins. They all have EF-hand-like domains, and differ from each other in the N-terminus. They are integral subunit components of native Kv4 channel complexes. They may regulate A-type currents, and hence neuronal excitability, in response to changes in intracellular calcium. This protein member also interacts with presenilin. Multiple alternatively spliced transcript variants encoding distinct isoforms have been identified for this gene.
Interactions
KCNIP4 has been shown to interact with PSEN2.
See also
Voltage-gated potassium channel |
https://en.wikipedia.org/wiki/Soil%20type | A soil type is a taxonomic unit in soil science. All soils that share a certain set of well-defined properties form a distinctive soil type. Soil type is a technical term of soil classification, the science that deals with the systematic categorization of soils. Every soil of the world belongs to a certain soil type. Soil type is an abstract term. In nature, you will not find soil types. You will find soils that belong to a certain soil type.
In hierarchical soil classification systems, soil types mostly belong to the higher or intermediate level. A soil type can normally be subdivided into subtypes, and in many systems several soil types can be combined to entities of higher category. However, in the first classification system of the United States (Whitney, 1909), the soil type was the lowest level and the mapping unit.
For the definition of soil types, some systems use primarily such characteristics that are the result of soil-forming processes (pedogenesis). An example is the German soil systematics. Other systems combine characteristics resulting from soil-forming processes and characteristics inherited from the parent material. Examples are the World Reference Base for Soil Resources (WRB) and the USDA soil taxonomy. Other systems do not ask whether the properties are the result of soil formation or not. An example is the Australian Soil Classification.
A convenient way to define a soil type is referring to soil horizons. However, this is not always possible because some very initial soils may not even have a clear development of horizons. For other soils, it may be more convenient to define the soil type just referring to some properties common to the whole soil profile. For example, WRB defines the Arenosols by their sand content. Many soils are more or less strongly influenced by human activities. This is reflected by the definition of many soil types in various classification systems.
Because soil type is a very general and widely used term, many soi |
https://en.wikipedia.org/wiki/Carctol | Carctol is an ineffective cancer treatment made by mixing eight Indian herbs. First promoted in 1968 by Nandlal Tiwari, it gained widespread popularity in United Kingdom.
Carctol has been aggressively marketed as being able to treat cancer and reduce the side-effects of chemotherapy. However, there is no medical evidence that it has any benefits whatsoever for people with cancer.
Background
Carctol is a herbal dietary supplement marketed with claims it is based on traditional ayurvedic medicine. Its ingredients include Hemidesmus indicus, Tribulus terrestris, Piper cubeba, Ammani vesicatoria, Lepidium sativum, Blepharis edulis, Smilax china, and Rheum australe (syn. R. emodi).
It was In 2009, Edzard Ernst wrote that it was still promoted in the United Kingdom; public relations companies hired by its sellers had garnered it wide coverage on the web and, according to the British Medical Journal, in the media generally.
Criticism
Edzard Ernst has noted a complete absence of any form of scientific evidence to assert that carctol is any beneficial to cancer patients. A few studies about the chemical composition of carctol along with inconclusive surveys of patients who used it were noted to be published in non-peer reviewed journals.
Cancer Research UK say of carctol, "available scientific evidence does not support its use for the treatment of cancer in humans".
Harriet A. Hall includes carctol among the biologically-based remedies promoted by naturopaths. Hall laments that frauds and quacks persistently try to take advantage of the vulnerability of cancer patients.
See also
List of ineffective cancer treatments
Naturopathy |
https://en.wikipedia.org/wiki/Uchronia%3A%20The%20Alternate%20History%20List | Uchronia: The Alternate History List is an online general-interest book database containing a bibliography of alternate history novels, stories, essays and other printed material. It is owned and operated by Robert B. Schmunk. Uchronia was twice selected as the Sci Fi Channel's "Sci Fi Site of the Week."
Background
Uchronia catalogues and chronicles over 3300 published alternate history novels, short stories, anthologies, collections, series, as well as including reference material and works published in other languages. Entries indicate the original publication date, the point of divergence and a brief synopsis of the plot. A search mechanism that can identify works by author, keyword or language of publication/translation is also included.
Uchronia features a couple of real-world timelines: one devoted to alternate histories published before the Golden Age of Science Fiction, and another offering a complex chronological outline of point of divergences of the entries.
Uchronia contains large cover art gallery and links to Amazon.com in order to obtain the listed alternate history books.
Uchronia also hosts the main website for the Sidewise Award for Alternate History.
See also
List of alternate history fiction
Uchronia |
https://en.wikipedia.org/wiki/Advanced%20Amiga%20Architecture%20chipset | The AAA chipset (Advanced Amiga Architecture) was intended to be the next-generation Amiga multimedia system designed by Commodore International. Initially begun as a secret project, the first design discussions were started in 1988, and after many revisions and redesigns the first silicon versions were fabricated in 1992–1993. The project was stymied in 1993 based on a lack of funds for chip revisions.
At the same time AAA started first silicon testing, the next generation Commodore chipset project was in progress. While AAA was a reinvention and huge upgrade of the Amiga architecture, project Hombre was essentially a clean slate. It took what was learned from Amiga and went in new directions, which included an on-chip CPU with a custom 3D instruction set, 16-bit and 24-bit chunky pixel display, and up to four 16-bit playfields running simultaneously. Hombre also embraced the PCI bus, which was seen as the future for main board interconnect and expansion going forward.
Design goals
AAA was slated to include numerous technologies.
32-bit CPU bus
32-bit and 64-bit graphics bus options.
256 deep CLUT entries 25-bit wide each (256 indirect colors indexed through 24-bit palette with extra genlock bit like AGA has). This mode runs in the native AmigaOS display.
Direct 16 bit-planes planar pixels without CLUT entries, since this mode doesn't contain a palette or a CLUT it requires some kind of ReTargetable Graphics (RTG) driver like chunky modes.
New Agnus/Alice replacement chip 'Andrea' with an updated 32-bit blitter and Copper which can handle chunky pixels.
A line-buffer chip with double buffering called 'Linda' provides higher resolution (up to 1280 x 1024). Linda also decompresses two new packed pixels (PACKLUT, PACKHY) on the fly.
Updated version of Paula called 'Mary' with 8 voices that can be assigned either to left or right channel; each channel has 16-bit resolution with up to 100 kHz sample rate; additionally it does 8-bit audio sampling input.
Dir |
https://en.wikipedia.org/wiki/Suillus%20viscidus | Suillus viscidus (commonly known as the sticky bolete) is an edible, uncommon mushroom in the genus Suillus. It associates with larch and is found throughout Europe and in Japan.
Description
The cap is hemispherical when young, later convex to flat, whitish grey or darker. It is up to 12 cm in diameter. It is slimy, and blotchy when old. The large, angular pores on the underside of the cap are coloured pallid to yellowish at first, but become darker with maturity. Young specimens bear a whitish partial veil which soon shreds, sometimes leaving fragments on the cap edge. The tubes are concolorous, and have a slightly decurrent stem attachment. The stem bears a thin, slimy, dark-coloured ring in the uppermost part of the stem which is sometimes lost in mature specimens. The stem is divided by the ring into a short lighter, yellowish section above, and a duller, greyish section below, which is viscid. The flesh is whitish, staining bluish, very soft and has a mild or non-distinct taste.
The spores are clay-coloured and ellipsoid or subfusiform in shape. Their dimensions are 10–12 by 4–5.5 μm.
It is an edible mushroom of low quality.
Habitat
Suillus viscidus forms an ectomycorrhizal association with larch (Larix) specifically, and its distribution is thus limited by the range of the host tree. It occurs throughout Europe, and also in Japan. In Europe, it is considered an uncommon to rare fungus and it is to be found in the same habitat as the common larch bolete, Suillus grevillei, and also the rare Suillus tridentinus. Fruiting bodies are found in groups among grass under larch, from summer to autumn. |
https://en.wikipedia.org/wiki/Tur%C3%A1n%27s%20brick%20factory%20problem | In the mathematics of graph drawing, Turán's brick factory problem asks for the minimum number of crossings in a drawing of a complete bipartite graph. The problem is named after Pál Turán, who formulated it while being forced to work in a brick factory during World War II.
A drawing method found by Kazimierz Zarankiewicz has been conjectured to give the correct answer for every complete bipartite graph, and the statement that this is true has come to be known as the Zarankiewicz crossing number conjecture. The conjecture remains open, with only some special cases solved.
Origin and formulation
During World War II, Hungarian mathematician Pál Turán was forced to work in a brick factory, pushing wagon loads of bricks from kilns to storage sites. The factory had tracks from each kiln to each storage site, and the wagons were harder to push at the points where tracks crossed each other. Turán was inspired by this situation to ask how the factory might be redesigned to minimize the number of crossings between these tracks.
Mathematically, this problem can be formalized as asking for a graph drawing of a complete bipartite graph, whose vertices represent kilns and storage sites, and whose edges represent the tracks from each kiln to each storage site.
The graph should be drawn in the plane with each vertex as a point, each edge as a curve connecting its two endpoints, and no vertex placed on an edge that it is not incident to. A crossing is counted whenever two edges that are disjoint in the graph have a nonempty intersection in the plane. The question is then, what is the minimum number of crossings in such a drawing?
Turán's formulation of this problem is often recognized as one of the first studies of the crossing numbers of graphs.
(Another independent formulation of the same concept occurred in sociology, in methods for drawing sociograms, and a much older puzzle, the three utilities problem, can be seen as a special case of the brick factory problem with three |
https://en.wikipedia.org/wiki/Rasiowa%E2%80%93Sikorski%20lemma | In axiomatic set theory, the Rasiowa–Sikorski lemma (named after Helena Rasiowa and Roman Sikorski) is one of the most fundamental facts used in the technique of forcing. In the area of forcing, a subset E of a poset (P, ≤) is called dense in P if for any p ∈ P there is e ∈ E with e ≤ p. If D is a family of dense subsets of P, then a filter F in P is called D-generic if
F ∩ E ≠ ∅ for all E ∈ D.
Now we can state the Rasiowa–Sikorski lemma:
Let (P, ≤) be a poset and p ∈ P. If D is a countable family of dense subsets of P then there exists a D-generic filter F in P such that p ∈ F.
Proof of the Rasiowa–Sikorski lemma
The proof runs as follows: since D is countable, one can enumerate the dense subsets of P as D1, D2, …. By assumption, there exists p ∈ P. Then by density, there exists p1 ≤ p with p1 ∈ D1. Repeating, one gets … ≤ p2 ≤ p1 ≤ p with pi ∈ Di. Then G = { q ∈ P: ∃ i, q ≥ pi} is a D-generic filter.
The Rasiowa–Sikorski lemma can be viewed as an equivalent to a weaker form of Martin's axiom. More specifically, it is equivalent to MA().
Examples
For (P, ≤) = (Func(X, Y), ⊇), the poset of partial functions from X to Y, reverse-ordered by inclusion, define Dx = {s ∈ P: x ∈ dom(s)}. If X is countable, the Rasiowa–Sikorski lemma yields a {Dx: x ∈ X}-generic filter F and thus a function F: X → Y.
If we adhere to the notation used in dealing with D-generic filters, {H ∪ G0: PijPt} forms an H-generic filter.
If D is uncountable, but of cardinality strictly smaller than 2ℵ0 and the poset has the countable chain condition, we can instead use Martin's axiom.
See also |
https://en.wikipedia.org/wiki/Green%20coffee%20extract | Green coffee extract is an extract of unroasted, green coffee beans. It is used in the Swiss water process for decaffeinating coffee. It has also been used as a weight-loss supplement and as an ingredient in other weight-loss products, although there is insufficient clinical evidence that it is effective or safe for such uses. In 2014, one of the primary trials showing benefit was retracted and the company that sponsored the study, Applied Food Sciences, was fined by the Federal Trade Commission for making baseless weight-loss claims using the flawed study. Green coffee extract can also be prepared as an infusion from green coffee beans.
Research
A 2011 review found tentative evidence that green coffee extract promotes weight loss; however, the quality of the evidence was poor. A larger 2017 review assessed the effects of chlorogenic acid, the main phenolic compound in green coffee extract, determining that human studies to date were of poor quality and that no conclusions could be drawn from them.
History
In April and September 2012, The Dr. Oz Show featured green coffee extract, and conducted its own non-scientific study as to its efficacy. The guest on that show, Lindsey Duncan, had been fined $9 million by the Federal Trade Commission for making deceptive and unsubstantiated claims related to green coffee products promoted on The Dr. Oz Show.
Controversy
Fortune magazine reported in June 2014 that the benefits of consuming green coffee bean extract had been largely disproved by studies to date, and that green coffee extract has been the subject of Federal Trade Commission action against a Florida company and the subject of Senate hearings against misleading advertising for weight loss products.
In May 2014, the Federal Trade Commission (FTC) charged the Florida-based manufacturers of a product called Pure Green Coffee with deceiving consumers with false weight loss claims. The FTC said that reliance on the Vinson study was deceptive since serious methodologi |
https://en.wikipedia.org/wiki/Gulaman | Gulaman, in Filipino cuisine, is a bar, or powdered form, of dried agar or carrageenan used to make jelly-like desserts. In common usage, it also usually refers to the refreshment sago't gulaman, sometimes referred to as samalamig, sold at roadside stalls and vendors.
History
Gracilaria, which produces agar, is known as gulaman or gulaman dagat in Tagalog. It has been harvested and used as food for centuries, eaten both fresh or sun-dried and turned into jellies. The earliest historical attestation is from the Vocabulario de la lengua tagala (1754) by the Jesuit priests Juan de Noceda and Pedro de Sanlucar, where golaman or gulaman was defined as "una yerva, de que se haze conserva a modo de Halea, naze en la mar" ("an herb, from which a jam-like preserve is made, grows in the sea"), with an additional entry for guinolaman to refer to food made with the jelly.
Gulaman can also be made from Eucheuma spp., which produces the similarly jelly-like carrageenan. Eucheuma is known as gusô or tambalang in the Visayan languages. Use of gusô to make jellies among the Visayans have been recorded in the even earlier Diccionario De La Lengua Bisaya, Hiligueina y Haraia de la isla de Panay y Sugbu y para las demas islas (c.1637) of the Augustinian missionary Alonso de Méntrida . In the book, Méntrida describes gusô as being cooked until it melts, and then allowed to congeal into a sour dish.
Description
Gulaman is the Filipino culinary use of agar, which is made of processed Gracilaria seaweed; or carrageenan derived from other farmed seaweed species like Eucheuma and Kappaphycus alvarezii which were first cultivated commercially in the Philippines.
It is usually sold dehydrated and formed into foot-long dry bars which are either plain or coloured. It is also commonly sold in powder form.
Uses
Gulaman bars are used in the various Filipino refreshments or desserts such as sago at gulaman, buko pandan, agar flan, halo-halo, fruit cocktail jelly, different varieties of Filipin |
https://en.wikipedia.org/wiki/Pelagic%20zone | The pelagic zone consists of the water column of the open ocean and can be further divided into regions by depth. The word pelagic is derived . The pelagic zone can be thought of as an imaginary cylinder or water column between the surface of the sea and the bottom. Conditions in the water column change with depth: pressure increases; temperature and light decrease; salinity, oxygen, micronutrients (such as iron, magnesium and calcium) all change. Somewhat analogous to stratification in the Earth's atmosphere, but depending on how deep the water is, the water column can be divided vertically into up to five different layers (illustrated in the diagram).
Marine life is affected by bathymetry (underwater topography) such as the seafloor, shoreline, or a submarine seamount, as well as by proximity to the boundary between the ocean and the atmosphere at the ocean surface, which brings light for photosynthesis, predation from above, and wind stirring up waves and setting currents in motion. The pelagic zone refers to the open, free waters away from the shore, where marine life can swim freely in any direction unhindered by topographical constraints.
The oceanic zone is the deep open ocean beyond the continental shelf, which contrasts with the inshore waters near the coast, such as in estuaries or on the continental shelf. Waters in the oceanic zone plunge to the depths of the abyssopelagic and further to the hadopelagic. Coastal waters are generally the relatively shallow epipelagic. Altogether, the pelagic zone occupies 1,330 million km3 (320 million mi3) with a mean depth of and maximum depth of . Pelagic life decreases as depth increases.
The pelagic zone contrasts with the benthic and demersal zones at the bottom of the sea. The benthic zone is the ecological region at the very bottom, including the sediment surface and some subsurface layers. Marine organisms such as clams and crabs living in this zone are called benthos. Just above the benthic zone is the deme |
https://en.wikipedia.org/wiki/Yusnier%20Viera | Yusnier Viera (born April 26, 1982) is a Cuban American mental calculator. He is well known as "The Human Calendar" for his world record on calendar dates. On October 31, 2005 he broke for first time the World Record for calendar calculations. At the Mental Calculation World Cup in 2010 he won the calendar category. His current record for most amount of calendar dates calculated in a minute is 132 dates. He currently has three World Records for calendar calculations.
Viera has appeared in prestigious TV channels like CNN & ABC and has starred on the international Discovery Channel Series "Superhuman Showdown" (trailer). In early 2014, he participated in the Latin American show "Super Cerebros", of NatGeo. He won the first round and $4,500 of cash prize, reaching the final round of the show.
Due to his extraordinary skills, University of Sussex neuroscientists took fMRI scans of his brain. In the study, he also completed a computerized version of the Raven's Progressive Matrices Test with an IQ score of 157 (standard deviation of 15). The scientists concluded that his expertise is a result of long-term practice and motivation.
On 2016, Yusnier participated in the Fox show "Superhumans" where he showed a new skill called "flash math". Later, he was invited to "The Ellen DeGeneres Show" for an impressive demonstration.
Recently, he published the books Basic Course of Mental Arithmetic and Master the Multiplication Tables.
Television Shows |
https://en.wikipedia.org/wiki/Stress%20functions | In linear elasticity, the equations describing the deformation of an elastic body subject only to surface forces (or body forces that could be expressed as potentials) on the boundary are (using index notation) the equilibrium equation:
where is the stress tensor, and the Beltrami-Michell compatibility equations:
A general solution of these equations may be expressed in terms of the Beltrami stress tensor. Stress functions are derived as special cases of this Beltrami stress tensor which, although less general, sometimes will yield a more tractable method of solution for the elastic equations.
Beltrami stress functions
It can be shown that a complete solution to the equilibrium equations may be written as
Using index notation:
{| class="collapsible collapsed" width="30%" style="text-align:left"
!Engineering notation
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where is an arbitrary second-rank tensor field that is at least twice differentiable, and is known as the Beltrami stress tensor. Its components are known as Beltrami stress functions. is the Levi-Civita pseudotensor, with all values equal to zero except those in which the indices are not repeated. For a set of non-repeating indices the component value will be +1 for even permutations of the indices, and -1 for odd permutations. And is the Nabla operator. For the Beltrami stress tensor to satisfy the Beltrami-Michell compatibility equations in addition to the equilibrium equations, it is further required that is at least four times continuously differentiable.
Maxwell stress functions
The Maxwell stress functions are defined by assuming that the Beltrami stress tensor is restricted to be of the form.
The stress tensor which automatically obeys the equilibrium equation may now be written as:
{|
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The solution to the elastostatic problem now consists of finding the three stress functions |
https://en.wikipedia.org/wiki/GraphExeter | GraphExeter is a material consisting of a few graphene sheets with a layer of ferric chloride molecules in between each graphene sheet. It was created by The Centre for Graphene Science at the University of Exeter in collaboration with the University of Bath.
See also
Carbon nanotubes
Graphene nanoribbons
Graphene oxide paper |
https://en.wikipedia.org/wiki/List%20of%20plant%20genus%20names%20with%20etymologies%20%28A%E2%80%93C%29 | Since the first printing of Carl Linnaeus's Species Plantarum in 1753, plants have been assigned one epithet or name for their species and one name for their genus, a grouping of related species. Many of these plants are listed in Stearn's Dictionary of Plant Names for Gardeners. William Stearn (1911–2001) was one of the pre-eminent British botanists of the 20th century: a Librarian of the Royal Horticultural Society, a president of the Linnean Society and the original drafter of the International Code of Nomenclature for Cultivated Plants.
The first column below contains seed-bearing genera from Stearn and other sources as listed, excluding those names that no longer appear in more modern works, such as Plants of the World by Maarten J. M. Christenhusz (lead author), Michael F. Fay and Mark W. Chase. Plants of the World is also used for the family and order classification for each genus. The second column gives a meaning or derivation of the word, such as a language of origin. The last two columns indicate additional citations.
Key
Latin: = derived from Latin (otherwise Greek, except as noted)
Ba = listed in Ross Bayton's The Gardener's Botanical
Bu = listed in Lotte Burkhardt's Index of Eponymic Plant Names
CS = listed in both Allen Coombes's The A to Z of Plant Names and Stearn's Dictionary of Plant Names for Gardeners
G = listed in David Gledhill's The Names of Plants
St = listed in Stearn's Dictionary of Plant Names for Gardeners
Genera
See also
Glossary of botanical terms
List of Greek and Latin roots in English
List of Latin and Greek words commonly used in systematic names
List of plant genera named for people: A–C, D–J, K–P, Q–Z
List of plant family names with etymologies
Notes
Citations |
https://en.wikipedia.org/wiki/Chemical%20bonding%20model | A chemical bonding model is a theoretical model used to explain atomic bonding structure, molecular geometry, properties, and reactivity of physical matter. This can refer to:
VSEPR theory, a model of molecular geometry.
Valence bond theory, which describes molecular electronic structure with localized bonds and lone pairs.
Molecular orbital theory, which describes molecular electronic structure with delocalized molecular orbitals.
Crystal field theory, an electrostatic model for transition metal complexes.
Ligand field theory, the application of molecular orbital theory to transition metal complexes.
Chemical bonding |
https://en.wikipedia.org/wiki/Nudix%20hydrolase | NUDIX hydrolases are a superfamily of hydrolytic enzymes capable of cleaving nucleoside diphosphates linked to x (any moiety), hence their name. The reaction yields nucleoside monophosphate (NMP) plus X-P. Substrates hydrolysed by nudix enzymes comprise a wide range of organic pyrophosphates, including nucleoside di- and triphosphates, dinucleoside and diphosphoinositol polyphosphates, nucleotide sugars and RNA caps, with varying degrees of substrate specificity. Enzymes of the NUDIX superfamily are found in all types of organisms, including eukaryotes, bacteria and archaea.
There are two components to the NUDIX family: the so-called NUDIX fold of a beta sheet with alpha helices on each side and the NUDIX motif which contains catalytic and metal-binding amino acids. The Nudix motif is GXXXXXEXXXXXXXREUXEEXGU where U is isoleucine, leucine or valine, and X is any amino acid. This forms a short helix which (usually) contains the catalytic amino acids. NUDIX hydrolases include Dcp2 of the decapping complex, ADP-ribose diphosphatase, MutT, ADPRase, Ap4A hydrolases, RppH, and many others. |
https://en.wikipedia.org/wiki/Galactic%20habitable%20zone | In astrobiology and planetary astrophysics, the galactic habitable zone is the region of a galaxy in which life might most likely develop. The concept of a galactic habitable zone analyzes various factors, such as metallicity (the presence of elements heavier than hydrogen and helium) and the rate and density of major catastrophes such as supernovae, and uses these to calculate which regions of a galaxy are more likely to form terrestrial planets, initially develop simple life, and provide a suitable environment for this life to evolve and advance. According to research published in August 2015, very large galaxies may favor the birth and development of habitable planets more than smaller galaxies such as the Milky Way. In the case of the Milky Way, its galactic habitable zone is commonly believed to be an annulus with an outer radius of about and an inner radius close to the Galactic Center (with both radii lacking hard boundaries).
Galactic habitable-zone theory has been criticized due to an inability to accurately quantify the factors making a region of a galaxy favorable for the emergence of life. In addition, computer simulations suggest that stars may change their orbits around the galactic center significantly, therefore challenging at least part of the view that some galactic areas are necessarily more life-supporting than others.
History
Background
The idea of the circumstellar habitable zone was introduced in 1953 by Hubertus Strughold and Harlow Shapley and in 1959 by Su-Shu Huang as the region around a star in which an orbiting planet could retain water at its surface. From the 1970s, planetary scientists and astrobiologists began to consider various other factors required for the creation and sustenance of life, including the impact that a nearby supernova may have on life's development. In 1981, computer scientist Jim Clarke proposed that the apparent lack of extraterrestrial civilizations in the Milky Way could be explained by Seyfert-type outbur |
https://en.wikipedia.org/wiki/Ageing%20Research%20Reviews | Ageing Research Reviews is a peer-reviewed scientific journal publishing review articles covering research on ageing, aging-associated diseases, and human life expectancy. The editor-in-chief is Claudio Franceschi (University of Bologna).
Abstracting and indexing
The journal is abstracted and indexed in:
BIOSIS
Chemical Abstracts
Current Contents/Life Sciences
Embase
FRANCIS
MEDLINE/PubMed
PASCAL
Scopus
According to the Journal Citation Reports, its 2022 impact factor is 13.1. |
https://en.wikipedia.org/wiki/Biomarker | In biomedical contexts, a biomarker, or biological marker, is a measurable indicator of some biological state or condition. Biomarkers are often measured and evaluated using blood, urine, or soft tissues to examine normal biological processes, pathogenic processes, or pharmacologic responses to a therapeutic intervention. Biomarkers are used in many scientific fields.
Medicine
Biomarkers used in the medical field, are a part of a relatively new clinical toolset categorized by their clinical applications. The four main classes are molecular, physiologic, histologic and radiographic biomarkers. All four types of biomarkers have a clinical role in narrowing or guiding treatment decisions and follow a sub-categorization of being either predictive, prognostic, or diagnostic.
Predictive
Predictive molecular, cellular, or imaging biomarkers that pass validation can serve as a method of predicting clinical outcomes. Predictive biomarkers are used to help optimize ideal treatments, and often indicate the likelihood of benefiting from a specific therapy. For example, molecular biomarkers situated at the interface of pathology-specific molecular process architecture and drug mechanism of action promise capturing aspects allowing assessment of an individual treatment response. This offers a dual approach to both seeing trends in retrospective studies and using biomarkers to predict outcomes. For example, in metastatic colorectal cancer predictive biomarkers can serve as a way of evaluating and improving patient survival rates and in the individual case by case scenario, they can serve as a way of sparing patients from needless toxicity that arises from cancer treatment plans.
Common examples of predictive biomarkers are genes such as ER, PR and HER2/neu in breast cancer, BCR-ABL fusion protein in chronic myeloid leukaemia, c-KIT mutations in GIST tumours and EGFR1 mutations in NSCLC.
Diagnostic
Diagnostic biomarkers that meet a burden of proof can serve a role in narrowi |
https://en.wikipedia.org/wiki/Hydrophosphination | Hydrophosphination is the insertion of a carbon-carbon multiple bond into a phosphorus-hydrogen bond forming a new phosphorus-carbon bond. Like other hydrofunctionalizations, the rate and regiochemistry of the insertion reaction is influenced by the catalyst. Catalysts take many forms, but most prevalent are bases and free-radical initiators. Most hydrophosphinations involve reactions of phosphine (PH3).
Acid-base routes
The usual application of hydrophosphination involves reactions of phosphine (PH3). Typically base-catalysis allows addition of Michael acceptors such as acrylonitrile to give tris(cyanoethyl)phosphine:
PH3 + 3 CH2=CHZ → P(CH2CH2Z)3 (Z = NO2, CN, C(O)NH2)
Acid catalysis is applicable to hydrophosphination with alkenes that form stable carbocations. These alkenes include isobutylene and many analogues:
PH3 + R2C=CH2 → R2(CH3)CPH2 (R = Me, alkyl, etc)
Bases catalyze the addition of secondary phosphines to vinyldiphenylphosphine:
HPR2 + CH2=CHPR'2 → R2PCH2CH2PR'2
Free-radical methods
Many hydrophosphination reactions are initiated by free-radicals. AIBN and peroxides are typical initiators, as well as Ultraviolet irradiation. In this way, the commercially important tributylphosphine and trioctylphosphine are prepared in good yields from 1-butene and 1-octene, respectively.
The reactions proceed by abstraction of an H atom the phosphine precursor, producing the phosphino radical, a seven electron species. This radical then adds to the alkene, and subsequent H-atom transfer completes the cycle. Some highly efficient hydrophosphinations appear not to proceed via radicals, but alternative explanations are lacking.
Metal-catalyzed reactions
Metal-catalyzed hydrophosphinations are not widely used, although they have been extensively researched. Studies mainly focus on secondary and primary organophosphines (R2PH and RPH2, respectively). These substrates bind to metals, and the resulting adducts insert alkenes and alkynes into the |
https://en.wikipedia.org/wiki/Flettner%20rotor%20bomblet | The Flettner rotor bomblet was a U.S. biological sub-munition that was never mass-produced. Based on the vertical Flettner rotor which takes advantage of the Magnus effect, a force acting on a spinning body in a moving airstream, it was developed toward the end of the U.S. biological weapons program in the 1960s.
History
The Flettner rotor biological bomblet was an experimental cluster bomb sub-munition developed by the U.S. Army during the 1960s, as the U.S. biological weapons program neared its end. The weapon was never standardized or mass-produced. William C. Patrick III said, in 1995, that the Flettner rotor was "probably one of the better devices for disseminating microorganisms."
Specifications
The Flettner rotor was seven inches long and winged. It could carry a liquid or dry biological agent and was designed to be used as a sub-munition in a missile warhead, cluster bomb or dispenser. The fins, or wings, were designed to extend by centrifugal force, thus stabilizing the bomblet as it flew to the target area. The Flettner rotor has a glide angle of 44 degrees. The Flettner rotor made it possible for a single B-52 to cover an area of 20,000 square kilometers with biological agent.
The Flettner rotor utilized the delayed action dissemination technique (DADT) fuse. This type of fuse has two functions. The first is that the internal fuse can initiate the gas expulsion system in the event of tampering, or certain environmental conditions. This DADT fuse also self-destructs after three days if the munition fails to dispense its agent on impact as designed. Fuses incorporating self-destruct mechanisms are considerably more expensive than traditional fuses.
See also
Rotor ship |
https://en.wikipedia.org/wiki/Insurance%20score | An insurance score – also called an insurance credit score – is a numerical point system based on select credit report characteristics. There is no direct relationship to financial credit scores used in lending decisions, as insurance scores are not intended to measure creditworthiness, but rather to predict risk. Insurance companies use insurance scores for underwriting decisions, and to partially determine charges for premiums. Insurance scores are applied in personal product lines, namely homeowners and private passenger automobile insurance, and typically not elsewhere.
Background
Insurance scoring models are built from selections of credit report factors, combined with insurance claim and profitability data, to produce numerical formulae or algorithms. A scoring model may be unique to an insurance company and to each line of business (e.g. homeowners or automobile), in terms of the factors selected for consideration and the weighting of the point assignments. As insurance credit scores are not intended to measure creditworthiness, they commonly focus on financial habits and choices (i.e., age of oldest account, number of inquiries in 24 months, ratio of total balance to total limits, number of open retail credit cards, number of revolving accounts with balances greater than 75% of limits, etc.) Therefore it is possible for a consumer with a high financial credit score, and excellent payment history, to receive a poor insurance score. Insurers consider credit report information in their underwriting and pricing decisions as a predictor of profitability and risk of loss.
Various studies have found a strong relationship between credit-based insurance scores and profitability or risk of loss. The scores are generally most predictive when little or no other information exists, such as in the case of clean driving records, or claims-free policies; in instances where past claims, points, or other similar information exist on record, the personal histories will ty |
https://en.wikipedia.org/wiki/List%20of%20video%20production%20companies | This incomplete list covers the ever-expanding field of video production, and the companies which produce video products, whether for private or commercial purposes. It includes both well-known companies as well as smaller, local companies that have made notable contributions to the field of video production.
Video production companies
APV (Asia Pacific Vision)
Seven Arts Pictures.
MRB Productions
Creative COW
Northern Upstart Ltd
Arnait Video Productions
HGV Video Productions
Isuma
Reeltime Pictures
Canyon Productions
Through a Glass Productions
Tongal
Sahelis Productions
MAA Productions
Filament Productions
Ragtag Productions
Once Films
See also
Video production
List of video artists
:Category:Television production companies of the United States
:Category:Film production companies of the United States
:Category:Mass media companies of the United States
External links
Video production companies
Video |
https://en.wikipedia.org/wiki/Orosomucoid | Orosomucoid (ORM) or alpha-1-acid glycoprotein (α1AGp, AGP or AAG) is an acute phase protein found in plasma. It is an alpha-globulin glycoprotein and is modulated by two polymorphic genes. It is synthesized primarily in hepatocytes and has a normal plasma concentration between 0.6–1.2 mg/mL (1–3% plasma protein). Plasma levels are affected by pregnancy, burns, certain drugs, and certain diseases, particularly HIV.
The only established function of ORM is to act as a carrier of basic and neutrally charged lipophilic compounds. In medicine, it is known as the primary carrier of basic (negatively charged) drugs (whereas albumin carries acidic (positively charged) and neutral drugs), steroids, and protease inhibitors. Aging causes a small decrease in plasma albumin levels; if anything, there is a small increase in alpha-1-acid glycoprotein. The effect of these changes on drug protein binding and drug delivery, however, appear to be minimal. AGP shows a complex interaction with thyroid homeostasis: AGP in low concentrations was observed to stimulate the thyrotropin (TSH) receptor and intracellular accumulation of cyclic AMP. High AGP concentrations, however, inhibited TSH signalling.
Alpha-1-acid glycoprotein has been identified as one of four potentially useful circulating biomarkers for estimating the five-year risk of all-cause mortality (the other three are albumin, very low-density lipoprotein particle size, and citrate).
Orosomucoid increases in amount in obstructive jaundices while diminishes in hepatocellular jaundice and in intestinal infections. |
https://en.wikipedia.org/wiki/Animals%20in%20ancient%20Greece%20and%20Rome | Animals had a variety of roles and functions in ancient Greece and Rome. Fish and birds were served as food. Species such as donkeys and horses served as work animals. The military used elephants. It was common to keep animals such as parrots, cats, or dogs as pets. Many animals held important places in the Graeco-Roman religion or culture. For example, owls symbolized wisdom and were associated with Athena. Humans would form close relationships with their animals in antiquity. Philosophers often debated about the nature of animals and humans. Many believed that the fundamental difference was that humans were capable of reason while animals were not. People such as Porphyry advocated for veganism.
Marine life
Fishing
For the ancient Greeks and Romans fishing served as a source of income, food, and entertainment. Fishes such as tuna, sturgeons, mackerel, jellyfish, anchovies, lobsters, sprat, red mullet, oysters, mussels, sea urchins, salted fish, squid, and octopus were popular meals in ancient Greece or Rome. Octopuses were stored in pots and they would be given as a gift. Fish was also used to make a popular condiment known as garum. Species such as Bluefin Tuna were expensive delicacies in ancient Greece. In ancient Rome, many fish species were delicacies. The poor had limited access to these fish. Fishes were also used to help guide seamen and as methods of foretelling the weather.
Ancient fisherman used nets, short rods, traps, and lines with hooks. Roman fishing lines would often have an artificial fly attached to the end of the line. These flies were made of small feathers and were made to imitate the insects that landed on the surface of the water. The ancient Greek word griphos referred to a type of fishing basket. Poseidon, or Neptune in Roman mythology carried a trident that is used for spearfishing. People would hunt and trap tuna through seine fishing. Traps such as the almadraba might have been used in ancient Rome. Fisherman would sell their goods |
https://en.wikipedia.org/wiki/Vaccine-preventable%20disease | A vaccine-preventable disease is an infectious disease for which an effective preventive vaccine exists. If a person acquires a vaccine-preventable disease and dies from it, the death is considered a vaccine-preventable death.
The most common and serious vaccine-preventable diseases tracked by the World Health Organization (WHO) are: diphtheria, Haemophilus influenzae serotype b infection, hepatitis B, measles, meningitis, mumps, pertussis, poliomyelitis, rubella, tetanus, tuberculosis, and yellow fever. The WHO reports licensed vaccines being available to prevent, or contribute to the prevention and control of, 31 vaccine-preventable infections.
Background
In 2012, the World Health Organization estimated that vaccination prevents 2.5 million deaths each year. With 100% immunization, and 100% efficacy of the vaccines, one out of seven deaths among young children could be prevented, mostly in developing countries, making this an important global health issue. Four diseases were responsible for 98% of vaccine-preventable deaths: measles, Haemophilus influenzae serotype b, pertussis, and neonatal tetanus.
The Immunization Surveillance, Assessment and Monitoring program of the WHO monitors and assesses the safety and effectiveness of programs and vaccines at reducing illness and deaths from diseases that could be prevented by vaccines.
Vaccine-preventable deaths are usually caused by a failure to obtain the vaccine in a timely manner. This may be due to financial constraints or to lack of access to the vaccine. A vaccine that is generally recommended may be medically inappropriate for a small number of people due to severe allergies or a damaged immune system. In addition, a vaccine against a given disease may not be recommended for general use in a given country, or may be recommended only to certain populations, such as young children or older adults. Every country makes its own immunization recommendations, based on the diseases that are common in its area and it |
https://en.wikipedia.org/wiki/Replicon%20%28genetics%29 | A replicon is a region of an organism's genome that is independently replicated from a single origin of replication. A bacterial chromosome contains a single origin, and therefore the whole bacterial chromosome is a replicon. The chromosomes of archaea and eukaryotes can have multiple origins of replication, and so their chromosomes may consist of several replicons. The concept of the replicon was formulated in 1963 by François Jacob, Sydney Brenner, and Jacques Cuzin as a part of their replicon model for replication initiation. According to the replicon model, two components control replication initiation: the replicator and the initiator. The replicator is the entire DNA sequence (including, but not limited to the origin of replication) required to direct the initiation of DNA replication. The initiator is the protein that recognizes the replicator and activates replication initiation.
Sometimes in bacteriology, the term "replicon" is only used to refer to chromosomes containing a single origin of replication and therefore excludes the genomes of archaea and eukaryotes which can have several origins.
Prokaryotes
For most prokaryotic chromosomes, the replicon is the entire chromosome. One notable exception comes from archaea, where two Sulfolobus species have been shown to contain three replicons. Examples of bacterial species that have been found to possess multiple replicons include Rhodobacter sphaeroides (two), Vibrio cholerae, and Burkholderia multivorans (three). These "secondary" (or tertiary) chromosomes are often described as molecules that are intermediate between a true chromosome and a plasmid and are sometimes called "chromids". Various Azospirillum species possess seven replicons; A. lipoferum, for instance, has one bacterial chromosome, five chromids, and one plasmid.
Plasmids and bacteriophages are usually replicated as single replicons, but large plasmids in Gram-negative bacteria have been shown to carry several replicons.
Eukaryotes
For eukar |
https://en.wikipedia.org/wiki/Musical%20prefix | A musical prefix is a numeral or other prefix used in music theory, specifically musical tuning.
See also
Limit (music)
List of pitch intervals
Musical terminology
Musical tuning
Prefixes |
https://en.wikipedia.org/wiki/Bacteriology | Bacteriology is the branch and specialty of biology that studies the morphology, ecology, genetics and biochemistry of bacteria as well as many other aspects related to them. This subdivision of microbiology involves the identification, classification, and characterization of bacterial species. Because of the similarity of thinking and working with microorganisms other than bacteria, such as protozoa, fungi, and viruses, there has been a tendency for the field of bacteriology to extend as microbiology. The terms were formerly often used interchangeably. However, bacteriology can be classified as a distinct science.
Overview
Definition
Bacteriology is the study of bacteria and their relation to medicine. Bacteriology evolved from physicians needing to apply the germ theory to address the concerns relating to disease spreading in hospitals the 19th century. Identification and characterizing of bacteria being associated to diseases led to advances in pathogenic bacteriology. Koch's postulates played a role into identifying the relationships between bacteria and specific diseases. Since then, bacteriology has played a role in successful advances in science such as bacterial vaccines like diphtheria toxoid and tetanus toxoid. Bacteriology can be studied and applied in many sub-fields relating to agriculture, marine biology, water pollution, bacterial genetics, veterinary medicine, biotechnology and others.
Bacteriologists
A bacteriologist is a microbiologist or other trained professional in bacteriology. Bacteriologists are interested in studying and learning about bacteria, as well as using their skills in clinical settings. This includes investigating properties of bacteria such as morphology, ecology, genetics and biochemistry, phylogenetics, genomics and many other areas related to bacteria like disease diagnostic testing. They can also work as medical scientists, veterinary scientists, or diagnostic technicians in locations like clinics, blood banks, hospitals |
https://en.wikipedia.org/wiki/Abask | Abask is an e-commerce platform focused on homeware and gifting products with headquarters in London.
It was founded in 2022 by Nicolas Pickaerts and Tom Chapman, the founders of the retailer Matches Fashion.
Abask's selection is focused on crafts and hand-made designs for the home, that can be shopped by room or style.
The initial launch offered four rooms: the dining room, the study, the games room and the bar. |
https://en.wikipedia.org/wiki/CCP4%20%28file%20format%29 | The CCP4 file format is file generated by the Collaborative Computational Project Number 4 in 1979. The file format for electron density has become industry standard in X-ray crystallography and Cryo-electron microscopy where the result of the technique is a three-dimensional grid of voxels each with a value corresponding to density of electrons (see wave function) The CCP4 format is supported by almost every molecular graphics suite that supports volumetric data. The major packages include:
Visual molecular dynamics
PyMOL
UCSF Chimera
Bsoft
Coot
MOE
See also
MTZ (file format)
MRC (file format)
EZD (file format)
Chemical file format
Protein Data Bank (file format)
Voxel - one way of presenting 3D densities
External links
Format technical details
Computational chemistry
Chemical file formats |
https://en.wikipedia.org/wiki/Dinosaur%20coloration | Dinosaur coloration is generally one of the unknowns in the field of paleontology, as skin pigmentation is nearly always lost during the fossilization process. However, recent studies of feathered dinosaurs and skin impressions have shown the colour of some species can be inferred through the use of melanosomes, the colour-determining pigments within the feathers.
Feathered dinosaurs
Anchiornis
In 2010, paleontologists studied a well-preserved skeleton of Anchiornis, an averaptoran from the Tiaojishan Formation in China, and found melanosomes within its fossilized feathers. As different shaped melanosomes determine different colours, analysis of the melanosomes allowed the paleontologists to infer that Anchiornis had black, white and grey feathers all over its body and a crest of dark red or ochre feathers on its head.
In 2015, another specimen was reported to possess melanosomes that induced grey and black coloration, but no red or brown coloration. This may have been because of different testing methods or a different age or species of the second tested specimen.
Archaeopteryx
In 2012, Ryan Carney and colleagues produced the first colour study on an Archaeopteryx specimen. Fossilized melanosomes suggested a primarily black coloration in the feathers of the specimen. The feather studied was likely a covert, which would have partly covered the primary feathers on the wings. Carney pointed out that this is consistent with the flight feathers of modern birds, in which black melanosomes have structural properties that strengthen feathers for flight.
In 2013, a study published in the Journal of Analytical Atomic Spectrometry by Manning et al. reported new analyses on the feather revealing that Archaeopteryx may have had light and dark coloured plumage, with only the tips of the feathers being primarily black instead of the entire feather. Whether or not this coloration was primarily for display or flight is currently unknown.
A follow-up study by Carney and co |
https://en.wikipedia.org/wiki/Global%20network%20positioning | Global network positioning is a coordinates-based mechanism in a peer-to-peer network architecture which predicts Internet network distance (i.e. round-trip propagation and transmission delay). The mechanism is based on absolute coordinates computed from modeling the Internet as a geometric space. Since end hosts maintain their own coordinates, the approach allows end hosts to compute their inter-host distances as soon as they discover each other. Moreover, coordinates are very efficient in summarizing inter-host distances, making the approach very scalable. |
https://en.wikipedia.org/wiki/Mitogen-activated%20protein%20kinase | A mitogen-activated protein kinase (MAPK or MAP kinase) is a type of protein kinase that is specific to the amino acids serine and threonine (i.e., a serine/threonine-specific protein kinase). MAPKs are involved in directing cellular responses to a diverse array of stimuli, such as mitogens, osmotic stress, heat shock and proinflammatory cytokines. They regulate cell functions including proliferation, gene expression, differentiation, mitosis, cell survival, and apoptosis.
MAP kinases are found in eukaryotes only, but they are fairly diverse and encountered in all animals, fungi and plants, and even in an array of unicellular eukaryotes.
MAPKs belong to the CMGC (CDK/MAPK/GSK3/CLK) kinase group. The closest relatives of MAPKs are the cyclin-dependent kinases (CDKs).
Discovery
The first mitogen-activated protein kinase to be discovered was ERK1 (MAPK3) in mammals. Since ERK1 and its close relative ERK2 (MAPK1) are both involved in growth factor signaling, the family was termed "mitogen-activated". With the discovery of other members, even from distant organisms (e.g. plants), it has become increasingly clear that the name is a misnomer, since most MAPKs are actually involved in the response to potentially harmful, abiotic stress stimuli (hyperosmosis, oxidative stress, DNA damage, low osmolarity, infection, etc.). Because plants cannot "flee" from stress, terrestrial plants have the highest number of MAPK genes per organism ever found. Thus the role of mammalian ERK1/2 kinases as regulators of cell proliferation is not a generic, but a highly specialized function.
Types
Most MAPKs have a number of shared characteristics, such as the activation dependent on two phosphorylation events, a three-tiered pathway architecture and similar substrate recognition sites. These are the "classical" MAP kinases. But there are also some ancient outliers from the group as sketched above, that do not have dual phosphorylation sites, only form two-tiered pathways, and lack the |
https://en.wikipedia.org/wiki/Stochastic%20Models | Stochastic Models is a peer-reviewed scientific journal that publishes papers on stochastic models. It is published by Taylor & Francis. It was established in 1985 under the title Communications in Statistics. Stochastic Models and obtained its current name in 2001. According to the Journal Citation Reports, the journal has a 2018 impact factor of 0.536. The founding editor-in-chief was Marcel F. Neuts, the current editor is Mark S. Squillante (IBM Thomas J. Watson Research Center). |
https://en.wikipedia.org/wiki/Selenosulfide | In chemistry, a selenosulfide refers to distinct classes of inorganic and organic compounds containing sulfur and selenium. The organic derivatives contain Se-S bonds, whereas the inorganic derivatives are more variable.
Organic selenosulfides
These species are classified as both organosulfur and organoselenium compounds. They are hybrids of organic disulfides and organic diselenides.
Preparation, structure, and reactivity
Selenosulfides have been prepared by the reaction of selenyl halides with thiols:
The equilibrium between diselenides and disulfides lies on the left:
RSeSeR + R'SSR' 2 RSeSR'
Because of the facility of this equilibrium, many of the best characterized examples of selenosulfides are cyclic, whereby S-Se bonds are stabilized intramolecularly. One example is the 1,8-selenosulfide of naphthalene. The selenium-sulfur bond length is about 220 picometers, the average of a typical S-S and Se-Se bond.
Occurrence
Selenosulfide groups can be found in almost all living organisms as part of various peroxidase enzymes, such as glutathione peroxidase and thioredoxin reductase. They are formed by the oxidative coupling of selenocysteine and cysteine residues. This reaction is powered by the decomposition of cellular peroxides, which can be highly damaging and a source of oxidative stress. Selenocysteine has a lower reduction potential than cysteine, making it very suitable for proteins that are involved in antioxidant activity.
Selenosulfides have been identified in some species of Allium and in roasted coffee. The mammalian version of the protein thioredoxin reductase contains a selenocysteine residue which forms a thioselenide (analogous to a disulfide) upon oxidation.
Inorganic selenosulfides
Some inorganic selenide sulfide compounds are also known. Simplest is the material selenium sulfide, which has medicinal properties. It adopt the diverse structures of elemental sulfur but with some S atoms replaced by Se.
Other inorganic selenide sulfid |
https://en.wikipedia.org/wiki/Deborah%20A.%20Nolan | Deborah A. Nolan is an American statistician and statistics educator. She is a professor of statistics at the University of California, Berkeley, where she chairs the department of statistics.
Education and career
Nolan graduated from Vassar College in 1977; she gained her first experience in statistics in a summer job at Vassar, doing statistical analyses for author Caroline Bird.
After graduating, she began working as an applications programmer for IBM.
Needing to learn more statistics for her work, she studied at Columbia University for a year, and then entered full-time graduate study in statistics at Yale University.
At Yale, the applied side of her research included work confirming the logarithmic spiral shape of snail shells.
Her dissertation, supervised by David Pollard, concerned central limit theorems, and was titled U-Processes.
She completed her Ph.D. in 1986, and became a faculty member at Berkeley in the same year, the first new female regular-rank faculty member in the department since Elizabeth Scott in 1951.
Books
Nolan is the author of several statistics books:
Stat Labs: Mathematical Statistics Through Applications (with Terry Speed, Springer, 2000)
Teaching Statistics: A Bag of Tricks (with Andrew Gelman, Oxford University Press, 2002)
XML and Web Technologies for Data Sciences with R (with Duncan Temple Lang, Springer, 2014)
Data Science in R: A Case Studies Approach to Computational Reasoning and Problem Solving (with Duncan Temple Lang, CRC Press, 2015)
Recognition
She is a fellow of the American Statistical Association and of the Institute of Mathematical Statistics. |
https://en.wikipedia.org/wiki/Alfiz | The alfiz (, from Andalusi Arabic alḥíz, from Standard Arabic alḥáyyiz, meaning 'the container';) is an architectural adornment, consisting of a moulding, usually a rectangular panel, which encloses the outward side of an arch. It is an architectonic ornament of Etruscan origin, used in Visigothic, Asturian, Moorish, Mozarabic, Mudéjar and Isabelline Gothic architecture.
It is frequent in the Islamic Hispanic art and Mozarabic art (usually in connection with the horseshoe arch). As the image illustrates, there are two alfiz variants:
Alfiz starting from the impost.
Alfiz starting from the floor.
The space between the arch and the alfiz is called enjuta or arrabá, usually richly decorated (iron-gray in the illustration). Each curved triangle is called albanega (spandrel). |
https://en.wikipedia.org/wiki/Loss%20of%20United%20Kingdom%20child%20benefit%20data%20%282007%29 | The loss of United Kingdom child benefit data was a data breach incident in October 2007, when two computer discs owned by HM Revenue and Customs containing data relating to child benefit went missing. The incident was announced by the Chancellor of the Exchequer, Alistair Darling, on 20 November 2007. The two discs contained the personal details of all families in the United Kingdom (UK) claiming child benefit, of which takeup in the UK is near 100%.
The loss
The discs were sent by junior staff at HM Revenue and Customs (HMRC) based at Waterview Park in Washington, Tyne and Wear, to the National Audit Office (NAO), as unrecorded internal mail via TNT on 18 October. On 24 October the NAO complained to HMRC that they had not received the data. On 8 November, senior officials in HMRC were informed of the loss, with Chancellor of the Exchequer, Alistair Darling being informed on 10 November. On 20 November Darling announced:
The lost data was thought to concern approximately 25 million people in the UK (nearly half of the country's population). The personal data on the missing discs was reported to include names and addresses of parents and children and dates of birth of the children, together with the National Insurance numbers and bank or building society details of their parents.
The "password protection" in question is that provided by WinZip version 8. This is a weak, proprietary scheme (unnamed encryption and hash algorithms) with well-known attacks. Anyone competent in computing would be able to break this protection by downloading readily-available tools. WinZip version 9 introduced AES encryption, which would have been secure and only breakable by correctly knowing the passphrase.
In a list of frequently asked questions, on the BBC News website a breakdown of the loss was reported as being:
7.25 million claimants
15.5 million children, including some who no longer qualify but whose family is claiming for a younger child
2.25 million 'alternative |
https://en.wikipedia.org/wiki/Diffraction%20topography | Diffraction topography (short: "topography") is a imaging technique based on Bragg diffraction.
Diffraction topographic images ("topographies") record the intensity profile of a beam of X-rays (or, sometimes, neutrons) diffracted by a crystal.
A topography thus represents a two-dimensional spatial intensity mapping of reflected X-rays, i.e. the spatial fine structure of a Laue reflection.
This intensity mapping reflects the distribution of scattering power inside the crystal; topographs therefore reveal the irregularities in a non-ideal crystal lattice.
X-ray diffraction topography is one variant of X-ray imaging, making use of diffraction contrast rather than absorption contrast which is usually used in radiography and computed tomography (CT). Topography is exploited to a lesser extends with neutrons, and has similarities to dark field imaging in the electron microscope community.
Topography is used for monitoring crystal quality and visualizing defects in many different crystalline materials.
It has proved helpful e.g. when developing new crystal growth methods, for monitoring growth and the crystal quality achieved, and for iteratively optimizing growth conditions.
In many cases, topography can be applied without preparing or otherwise damaging the sample; it is therefore one variant of non-destructive testing.
History
After the discovery of x-rays by Wilhelm Röntgen in 1895, and of the principles of X-ray diffraction by Laue and the Bragg family, it still took several decades for the benefits of diffraction imaging to be fully recognized, and the first useful experimental techniques to be developed. First systematic reports on laboratory topography techniques date from the early 1940s. In the 1950s and 1960s, topographic investigations played a role in detecting the nature of defects and improving crystal growth methods for Germanium and (later) Silicon as materials for semiconductor microelectronics.
For a more detailed account of the historical developme |
https://en.wikipedia.org/wiki/Enzyme%20repressor | An enzyme repressor is a substance that negatively regulates the amount of an enzyme by decreasing the rate of its biosynthesis. It is the opposite of an enzyme inducer.
See also
Enzyme activator
Enzyme inhibitor
Regulation of gene expression |
https://en.wikipedia.org/wiki/Hosted%20desktop | A hosted desktop is a product set within the larger cloud-computing sphere generally delivered using a combination of technologies including hardware virtualization and some form of remote connection software, Citrix XenApp or Microsoft Remote Desktop Services being two of the most common. Processing takes place within the provider's datacentre environment with traffic between the datacentre and the client being primarily display updates, mouse movements and keyboard activity (additional traffic will be generated by audio & print jobs).
A hosted desktop commonly involves a browser-based connection to a desktop environment which includes an office productivity suite alongside other desktop applications. The desktop is hosted, run, delivered and supported from a central location, usually a secure data center with high-quality and resilient connections to the Internet/cloud. Cloud Desktop is a term often used to refer to a container of a collection of virtual objects, software, hardware, configurations etc., residing on the cloud, used by a client to interact with remote services and perform computer related tasks.
Connecting clients run pre-installed or downloaded viewer applications via one of many remote desktop protocols. Clients can include thin clients, PCs, workstations, mobile and handheld devices running a variety of operating systems such as Windows, Mac OS X, Linux and others.
The move towards hosted desktops, of which virtual desktop infrastructure (VDI) is a subset, is predicted by Gartner to account for 49 million business desktops by 2013 equal to more than 40 percent of the worldwide professional PC market. The development of applications by service providers such as Google and Microsoft have accelerated this process, as has the evolution of new licensing schemes which allow fee-paying based on a subscription rather than on purchase.
Key characteristics
The centralized nature of hosted desktops can overcome common issues with mobile working, delive |
https://en.wikipedia.org/wiki/Virtual%20finite-state%20machine | A virtual finite-state machine (VFSM) is a finite-state machine (FSM) defined in a Virtual Environment. The VFSM concept provides a software specification method to describe the behaviour of a control system using assigned names of input control properties and output actions.
The VFSM method introduces an execution model and facilitates the idea of an executable specification. This technology is mainly used in complex machine control, instrumentation, and telecommunication applications.
Why
Implementing a state machine necessitates the generation of logical conditions (state transition conditions and action conditions). In the hardware environment, where state machines found their original use, this is trivial: all signals are Boolean. In contrast state machines specified and implemented in software require logical conditions that are per se multivalued:
Temperature could be Low, OK, High
Commands may have several values: Init, Start, Stop, Break, Continue
In a hierarchical control system the subordinate state machines can have many states that are used as conditions of the superior state machine
In addition input signals can be unknown due to errors or malfunctions, meaning even digital input signals (considered as classical Boolean values) are in fact 3 values: Low, High, Unknown.
A Positive Logical Algebra solves this problem via virtualization, by creating a Virtual Environment which allows specification of state machines for software using multivalued variables.
Control Properties
A state variable in the VFSM environment may have one or more values which are relevant for the Control—in such a case it is an input variable. Those values are the control properties of this variable. Control properties are not necessarily specific data values but are rather certain states of the variable. For instance, a digital variable could provide three control properties: TRUE, FALSE and UNKNOWN according to its possible boolean values. A numerical (analog) input vari |
https://en.wikipedia.org/wiki/Monatin | Monatin, commonly known as arruva, is a naturally occurring, high intensity sweetener isolated from the plant Sclerochiton ilicifolius, found in the Transvaal region of South Africa. Monatin contains no carbohydrate or sugar, and nearly no food energy, unlike sucrose or other nutritive sweeteners.
The name "monatin" is derived from the indigenous word for it, "molomo monate," which literally means "mouth nice."
Monatin is an indole derivative and, upon degradation, smells like feces.
It is 3000 times sweeter than sugar.
See also
Sugar substitute |
https://en.wikipedia.org/wiki/Gendered%20sexuality | Gendered sexuality is the way in which gender and sexuality are often viewed as likened constructs, whereby the role of gender in an individual's life is informed by and impacts others' perceptions of their sexuality. For example, both the male and female genders are subject to assumptions of heterosexuality. If a man were to behave in feminine ways, his heterosexuality would be doubted, and individuals may assume that he is gay.
Two main theoretical perspectives dominate discussions of gendered sexuality: that of an evolutionary perspective, and that of a sociocultural perspective. Although these two are typically separate, Eagly & Wood believe that these two theories could potentially be reconcilable.
Gender and sex in gendered sexuality
Both the terms gender and sex have been historically interchangeable, but it was not until the late 1960s and early 70s that the term gender began to be more thoroughly defined and spread throughout the literature within the field of psychology. Although the term has undergone some changes since then, today it represents how an individual feels and expresses their gender, typically through masculinity or femininity. Through this definition, gender has often been used as a variable to study how particular parts of people, (i.e. one's sexuality), can ultimately be informed by gender. Psychological research in this area has tended to follow these three modes of looking at gender:
Looking at gender through difference in presentation, actions, and traits
Looking at gender vs. individual difference in individuals who identify as male and individuals who identify as female, and
Looking at how gender influences how both men and women operate in society
Human sexuality, unlike gender, has kept a relatively stable definition by which it refers to all sexual attitudes and behaviours in an erotic, or lack of erotic, nature. The relationship between gender and sexuality is not static, it is fluid and changing. In light of this, gende |
https://en.wikipedia.org/wiki/Fungal%20prion | A fungal prion is a prion that infects hosts which are fungi. Fungal prions are naturally occurring proteins that can switch between multiple, structurally distinct conformations, at least one of which is self-propagating and transmissible to other prions. This transmission of protein state represents an epigenetic phenomenon where information is encoded in the protein structure itself, instead of in nucleic acids. Several prion-forming proteins have been identified in fungi, primarily in the yeast Saccharomyces cerevisiae. These fungal prions are generally considered benign, and in some cases even confer a selectable advantage to the organism.
Fungal prions have provided a model for the understanding of disease-forming mammalian prions. Study of fungal prions has led to a characterisation of the sequence features and mechanisms that enable prion domains to switch between functional and amyloid-forming states.
Sequence features
Prions are formed by portable, transmissible prion domains that are often enriched in asparagine, glutamine, tyrosine and glycine residues. When a reporter protein is fused with a prion domain, it forms a chimeric protein that demonstrates the conformational switching that is characteristic of prions. Meanwhile, removing this prion domain prevents prionogenesis. This suggests that these prion domains are, in fact, portable and are the sole initiator of prionogenesis. This supports the protein-only hypothesis.
A recent study of candidate prion domains in S. cerevisiae found several specific sequence features that were common to proteins showing aggregation and self-templating properties. For example, proteins that aggregated had candidate prion domains that were more highly enriched in asparagine, while non-aggregating domains where more highly enriched in glutamine and charged peptides. There was also evidence that the spacing of charged peptides that prevent amyloid formation, such as proline, is important in prionogenesis. This discovery |
https://en.wikipedia.org/wiki/Culture.pl | Culture.pl is a large web portal devoted to Polish culture. It was founded by the Adam Mickiewicz Institute in March 2001. Written in Polish, English and Russian, the site promotes the work of Polish artists around the world and is a popular information database on all artistic aspects of Polish culture. Its ISSN number is 1734-0624.
Structure
As well as acting as a database and magazine on Polish culture, the site promotes cultural events organised by its parent organisation the Adam Mickiewicz Institute. According to its website, as of 2015 Culture.pl has around 38,000 articles (8,000 of which are in English) shared across categories including Music, Visual Arts, Film, Theatre, Dance, Language & Literature, Comics, Heritage, Architecture, Photography, and Design. While a large part of the site is on Polish artists and their works, there is also information on around 700 cultural institutions such as museums, galleries, philharmonic halls, theatres and art schools. Many articles are written in English and specifically aimed at international audiences.
The portal was founded in March 2001. The project was initially conceived and designed by Andrzej Lubomirski, who also acted as editor-in-chief until 2008. Subsequent editors-in-chief included Monika Rencławowicz (2008–2009), Elżbieta Sawicka (2009–2012) and Weronika Kostyrko (2012–2016). The site went on to expand its offering with multimedia guides and podcasts.
In June 2016, Culture.pl released four multimedia guides developed with Bright Media called A Foreigner's Guide to Polish Culture, covering the fields of cinema, electronic music and photography, as well as the Polish alphabet.
In August 2017, Culture.pl's English section released their first podcast, called Stories From The Eastern West. The podcast is advertised as 'little-known histories from Central and Eastern Europe that changed our world'. In August 2019, the team released a mini-series called The Final Curtain about the collapse of the Eastern |
https://en.wikipedia.org/wiki/Oryza%20longistaminata | Oryza longistaminata is a perennial species of grass from the same genus as cultivated rice (O. sativa). It is native to most of sub-Saharan Africa and Madagascar. It has been introduced into the United States, where it is often regarded as a noxious weed. Its common names are longstamen rice and red rice.
The host resistance gene, Xa21, from O. longistaminata, has been integrated into the genome of O. sativa as it confers broad resistance to rice blight disease caused by Xanthomonas oryzae pv. oryzae.
Distribution
O. longistaminata is native throughout Africa. |
https://en.wikipedia.org/wiki/Halorhabdus | Halorhabdus is a genus of halophilic archaea in the Haloarculaceae. With an extremely high salinity optimum of 27% NaCl, Halorhabdus has one of the highest reported salinity optima of any living organism. |
https://en.wikipedia.org/wiki/Graphical%20timeline%20of%20prehistoric%20life |
Timeline
Paleontology
Paleontology timelines |
https://en.wikipedia.org/wiki/Microsoft%20Windows%20SDK | Microsoft Windows SDK, and its predecessors Platform SDK, and .NET Framework SDK, are software development kits (SDKs) from Microsoft that contain documentation, header files, libraries, samples and tools required to develop applications for Microsoft Windows and .NET Framework. Platform SDK specializes in developing applications for Windows 2000, XP and Windows Server 2003. .NET Framework SDK is dedicated to developing applications for .NET Framework 1.1 and .NET Framework 2.0. Windows SDK is the successor of the two and supports developing applications for Windows XP and later, as well as .NET Framework 3.0 and later.
Features
Platform SDK is the successor of the original Microsoft Windows SDK for Windows 3.1x and Microsoft Win32 SDK for Windows 9x. It was released in 1999 and is the oldest SDK. Platform SDK contains compilers, tools, documentations, header files, libraries and samples needed for software development on IA-32, x64 and IA-64 CPU architectures. however, came to being with .NET Framework. Starting with Windows Vista, the Platform SDK, .NET Framework SDK, Tablet PC SDK and Windows Media SDK are replaced by a new unified kit called Windows SDK. However, the .NET Framework 1.1 SDK is not included since the .NET Framework 1.1 does not ship with Windows Vista. (Windows Media Center SDK for Windows Vista ships separately.) DirectX SDK was merged into Windows SDK with the release of Windows 8.
Windows SDK allows the user to specify the components to be installed and where to install them. It integrates with Visual Studio, so that multiple copies of the components that both have are not installed; however, there are compatibility caveats if either of the two is not from the same era. Information shown can be filtered by content, such as showing only new Windows Vista content, only .NET Framework content, or showing content for a specific language or technology.
Windows SDKs are available for free; they were once available on Microsoft Download Center bu |
https://en.wikipedia.org/wiki/Peter%20Winkler | Peter Mann Winkler is a research mathematician, author of more than 125 research papers in mathematics and patent holder in a broad range of applications, ranging from cryptography to marine navigation. His research areas include discrete mathematics, theory of computation and probability theory.
He is currently a professor of mathematics and computer science at Dartmouth College.
Peter Winkler studied mathematics at Harvard University and later received his PhD in 1975 from Yale University under the supervision of Angus McIntyre. He has also served as an assistant professor at Stanford, full professor and chair at Emory and as a mathematics research director at Bell Labs and Lucent Technologies. He was visiting professor at the Technische Universität Darmstadt.
He has published three books on mathematical puzzles: Mathematical Puzzles: A connoisseur's collection (A K Peters, 2004, ), Mathematical Mind-Benders (A K Peters, 2007, ), and Mathematical Puzzles (A K Peters, 2021, ). And he is widely considered to be a pre eminent scholar in this domain. He was the Visiting Distinguished Chair for Public Dissemination of Mathematics at the National Museum of Mathematics (MoMath), gave topical talks at the Gathering 4 Gardner conferences, and wrote novel papers related to some of these puzzles.
Winkler's book Bridge at the Enigma Club was a runner up for the 2011 Master Point Press Book Of The Year award.
Also in 2011, Winkler received the David P. Robbins Prize of the Mathematical Association of America as coauthor of one of two papers in the American Mathematical Monthly.
Paul Erdős anecdote
According to a story included in Chapter One of "The Man Who Loved Only Numbers / The Story of Paul Erdös and the Search for Mathematical Truth", Paul Erdős attended the bar mitzvah celebration for Peter Winkler's twins, and Winkler's mother-in-law tried to throw Erdős out. [Quote:]"Erdös came to my twins' bar mitzvah, notebook in hand," said Peter Winkler, a colleague of Grah |
https://en.wikipedia.org/wiki/Glucokinase%20regulatory%20protein | The glucokinase regulatory protein (GKRP) also known as glucokinase (hexokinase 4) regulator (GCKR) is a protein produced in hepatocytes (liver cells). GKRP binds and moves glucokinase (GK), thereby controlling both activity and intracellular location of this key enzyme of glucose metabolism.
GKRP is a 68 kD protein of 626 amino acids. It is coded for by a 19 exon gene, GCKR, on the short arm of chromosome 2 (2p23). GKRP was discovered by Emile van Schaftingen and reported in 1989
Physiological function
Glucokinase (GK) in liver cells phosphorylates glucose, preparing it for incorporation into glycogen or for glycolysis. During periods of ample glucose supply, most GK activity can be found in the peripheral cytoplasm where glycogen synthesis is occurring. As the glucose supply declines during periods of fasting, GK activity in the cytoplasm diminishes. GKRP participates in this modulation of GK activity and location by binding free cytoplasmic GK as glucose levels decline, and moving it into the nucleus, where it is held in reserve in an inactive form. As glucose and insulin levels rise, as during digestion of a meal, GK is released from GKRP and moves back to the cytoplasm, where much of it associates with the bifunctional enzyme.
In hepatocytes of various mammals, GKRP has always been found in molar excess of the amount of GK, but the GKRP:GK ratio varies according to diet, insulin sufficiency, and other factors. Free GKRP shuttles between the nucleus and the cytoplasm. It may be attached to the microfilament cytoskeleton.
GKRP competes with glucose to bind with GK, but inactivates it when bound. In conditions of low glucose, GKRP then pulls the GK into the nucleus. Rising amounts of glucose coming into the hepatocyte prompt the GKRP to rapidly release GK to return to the cytoplasm.
GKRP itself is subject to modulation. Fructose and sorbitol can both be converted to fructose-1-phosphate, which inhibits GKRP and frees GK. Fructose 6-phosphate binds to the sa |
https://en.wikipedia.org/wiki/Homothorax | Homothorax (HTH or HTX) is a transcriptional co-factor to Hox genes that is closely connected with extradenticle. It may play a role in the identification of segments during panarthropod development. The gene acts in a similar way across the panarthropod phyla, although its expression pattern is reversed in the millipedes, centipedes and crustaceans. |
https://en.wikipedia.org/wiki/74%20%28number%29 | 74 (seventy-four) is the natural number following 73 and preceding 75.
In mathematics
74 is:
the twenty-first distinct semiprime and the eleventh of the form (2.q), where q is a higher prime.
with an aliquot sum of 40, within an aliquot sequence of three composite numbers (74,40,50,43,1,0) to the Prime in the 43-aliquot tree.
a palindromic number in bases 6 (2026) and 36 (2236).
a nontotient.
the number of collections of subsets of {1, 2, 3} that are closed under union and intersection.
φ(74) = φ(σ(74)).
There are 74 different non-Hamiltonian polyhedra with a minimum number of vertices.
In science
The atomic number of tungsten
In astronomy
Messier object M74, a magnitude 10.5 spiral galaxy in the constellation Pisces.
The New General Catalogue object NGC 74, a galaxy in the constellation Andromeda.
In music
Seventy-four, one of the Number Pieces by John Cage
"Seventy-Four", a song by the American band Bright from the album The Albatross Guest House
In other fields
Seventy-four is also:
The year AD 74, 74 BC, or 1974
Designates the 7400 series of Integrated Chips. 74xx xx=00-4538
A seventy-four was a third-rate warship with 74 guns.
The registry of the U.S. Navy's nuclear aircraft carrier USS John C. Stennis (CVN-74), named after U.S. Senator John C. Stennis
A hurricane or typhoon is a system with sustained winds of at least 74 mph (64 knots).
The number of the French department Haute-Savoie
In the Bible it is the number of people that were in the presence of God on Mount Sinai and saw God without dying "Exodus 24:9-11" |
https://en.wikipedia.org/wiki/Sum%20%28Unix%29 | is a legacy utility available on some Unix and Unix-like operating systems. This utility outputs a 16-bit checksum of each argument file, as well as the number of blocks they take on disk. Two different checksum algorithms are in use. POSIX abandoned sum in favor of cksum.
Overview
The program is generally only useful for historical interest. It is not part of POSIX. Two algorithms are typically available: a BSD checksum and a SYSV checksum. Both are weaker than the already weak 32-bit CRC used by cksum.
The default algorithm on FreeBSD and GNU implementations is the BSD checksum. Switching between the two algorithms is done via command line options.
The two commonly used algorithms are as follows.
The BSD sum, -r in GNU sum and -o1 in FreeBSD cksum:
Initialize checksum to 0
For each byte of the input stream
Perform 16-bit bitwise right rotation by 1 bit on the checksum
Add the byte to the checksum, and apply modulo 2 ^ 16 to the result, thereby keeping it within 16 bits
The result is a 16-bit checksum
The above algorithm appeared in Seventh Edition Unix.
The System V sum, -s in GNU sum and -o2 in FreeBSD cksum:
checksum0 = sum of all bytes of the input stream modulo 2 ^ 32
checksum1 = checksum0 modulo 2 ^ 16 + checksum0 / 2 ^ 16
checksum = checksum1 modulo 2 ^16 + checksum1 / 2 ^ 16
The result is a 16-bit checksum calculated from the initial 32-bit plain byte sum
Syntax
The utility is invoked from the command line according to the following syntax:
sum [OPTION]... [FILE]...
with the possible option parameters being:
use BSD checksum algorithm, use 1K blocks (defeats )
,
use SYSV checksum algorithm, use 512 bytes blocks
display the help screen and exit
output version information and exit
When no file parameter is given, or when FILE is , the standard input is used as input file.
Example of use:
$ echo Hello > testfile
$ sum testfile
36978 1
Example of -s use in GNU sum:
$ echo Hello > testfile
$ sum -s testfile
510 1 testfile
E |
https://en.wikipedia.org/wiki/Stellate%20veins | The stellate veins are veins that lie beneath the fibrous tunic of the kidney. They are stellate in arrangement and are derived from the capillary network, into which the terminal branches of the interlobular arteries break up. These join to form the interlobular veins, which pass inward between the rays.
See also
renal circulation |
https://en.wikipedia.org/wiki/Unfriendly%20partition | In the mathematics of infinite graphs, an unfriendly partition or majority coloring is a partition of the vertices of the graph into disjoint subsets, so that every vertex has at least as many neighbors in other sets as it has in its own set. It is a generalization of the concept of a maximum cut for finite graphs, which is automatically an unfriendly partition. (If not, a vertex with more neighbors in its own set could be moved to the other set, increasing the number of cut edges.) The unfriendly partition conjecture is an unsolved problem asking whether every countable graph has an unfriendly partition into two subsets.
Robert H. Cowan and William R. Emerson, in unpublished work, conjectured that every infinite graph has an unfriendly partition into two subsets. However, Saharon Shelah and Eric Charles Milner disproved the conjecture, showing that uncountable graphs might not have two-subset unfriendly partitions. Nevertheless, they showed that an unfriendly partition into three subsets always exists.
Among countable graphs, the existence of a two-subset unfriendly partition is known for the following special cases:
Graphs that have finitely many vertices of infinite degree
Graphs in which all vertices have infinite degree, by an argument using the back-and-forth method
Graphs with no end
Graphs without a subdivision of an infinite clique
The case for arbitrary countable graphs remains open. |
https://en.wikipedia.org/wiki/Dispersion%20%28materials%20science%29 | In materials science, dispersion is the fraction of atoms of a material exposed to the surface. In general, D = NS/N, where D is the dispersion, NS is the number of surface atoms and NT is the total number of atoms of the material. It is an important concept in heterogeneous catalysis, since only atoms exposed to the surface can affect catalytic surface reactions. Dispersion increases with decreasing crystallite size and approaches unity at a crystallite diameter of about 0.1 nm.
See also
Emulsion dispersion |
https://en.wikipedia.org/wiki/Allegro%20%28software%20library%29 | Allegro is a software library for video game development. The functionality of the library includes support for basic 2D graphics, image manipulation, text output, audio output, MIDI music, input and timers, as well as additional routines for fixed-point and floating-point matrix arithmetic, Unicode strings, file system access, file manipulation, data files, and 3D graphics. The library is written in the C programming language and designed to be used with C, C++, or Objective-C, with bindings available for Python, Lua, Scheme, D, Go, and other languages. Allegro comes with extensive documentation and many examples.
Allegro supports Windows, macOS, Unix-like systems, Android, and iOS, abstracting their application programming interfaces (APIs) into one portable interface. It can run also on top of Simple DirectMedia Layer which is used to run Allegro programs in web browser using Emscripten.
Released under the terms of the zlib license, Allegro is free and open source software.
History
Initially standing for Atari Low-Level Game Routines, Allegro was originally created by for the Atari ST in the early 1990s. However, Hargreaves abandoned the Atari version as he realized the platform was dying, and reimplemented his work for the Borland C++ and DJGPP compilers in 1995. Support for Borland C++ was dropped in version 2.0, and DJGPP was the only supported compiler. As DJGPP was a DOS compiler, all games which used Allegro therefore used DOS. Around 1998, Allegro branched out into several versions. A port to Windows, WinAllegro, was created, and also during this time, a Unix port of Allegro, XwinAllegro, was created. These various ports were brought together during the Allegro 3.9 WIP versions, with Allegro 4.0 being the first stable version of Allegro to support multiple platforms.
Allegro 5
Current development is focused on the Allegro 5 branch, a complete redesign of both the API and much of the library's internal operation. Effort was made to make the API mor |
https://en.wikipedia.org/wiki/Tardive%20dysmentia | Tardive dysmentia is a rarely used term introduced in a 1983 paper to describe "changes in affect, activation level, and interpersonal interaction", and hypothesized to be caused by long-term exposure to neuroleptic drugs in the same way as the much better-known syndrome of tardive dyskinesia. Several papers in the following years discussed the validity of the concept, and this small literature was reviewed in a 1993 publication by M. S. Myslobodsky, who drew attention to the "possibility that the syndrome of dysmentia is occasional excessive emotional reactivity, enhanced responsiveness to environmental stimuli, and indifference to or reduced awareness of the patient's abnormal involuntary movements", but concluded that the pathophysiology was uncertain. Since then, the term has fallen into disuse, receiving at most only passing mentions in the literature. |
https://en.wikipedia.org/wiki/Exokernel | Exokernel is an operating system kernel developed by the MIT Parallel and Distributed Operating Systems group, and also a class of similar operating systems.
Operating systems generally present hardware resources to applications through high-level abstractions such as (virtual) file systems. The idea behind exokernels is to force as few abstractions as possible on application developers, enabling them to make as many decisions as possible about hardware abstractions. Exokernels are tiny, since functionality is limited to ensuring protection and multiplexing of resources, which is considerably simpler than conventional microkernels' implementation of message passing and monolithic kernels' implementation of high-level abstractions.
Implemented abstractions are called library operating systems; they may request specific memory addresses, disk blocks, etc. The kernel only ensures that the requested resource is free, and the application is allowed to access it. This low-level hardware access allows the programmer to implement custom abstractions, and omit unnecessary ones, most commonly to improve a program's performance. It also allows programmers to choose what level of abstraction they want, high, or low.
Exokernels can be seen as an application of the end-to-end principle to operating systems, in that they do not force an application program to layer its abstractions on top of other abstractions that were designed with different requirements in mind. For example, in the MIT Exokernel project, the Cheetah web server stores preformatted Internet Protocol packets on the disk, the kernel provides safe access to the disk by preventing unauthorized reading and writing, but how the disk is abstracted is up to the application or the libraries the application uses.
Motivation
Traditionally kernel designers have sought to make individual hardware resources invisible to application programs by requiring the programs to interact with the hardware via some abstraction model. |
https://en.wikipedia.org/wiki/Clesh | Clesh (clip load edit share) is a cloud-based video editing platform designed for the consumers, prosumers, and online communities to integrate user-generated content. The core technology is based on FORscene which is geared towards professionals working for example in broadcasting, news media, post production.
Video, audio, and graphical content is uploaded to Clesh via a standard web browser, a mobile device such as a phone / tablet, or desktop software for DV capture over FireWire. The hosted material can then be reviewed, searched, edited, and published online by anyone with a standard web browser or compatible mobile device.
Clesh supports storyboard shot selection, frame-accurate editing, transitions and various other functions such as; pan, zoom, colour and light correction, and audio levels. Content can be published in formats for example; Podcast, Mpeg2, HTML5 video or in a proprietary Java format.
Cloud-based software provides greater scope for sharing information and collaborating compared to LAN or desktop based systems. Users of cloud-based software rely on the cloud's owner for adequate security, performance and resilience.
Clesh does not assert any rights over uploaded content in contrast to other platforms (such as YouTube). All rights to any content uploaded to Clesh remain with the Author.
Features
Some of the services available to Clesh users:
Access via Java enabled desktops or Android smartphones or tablets
Real-time video rendering including effects and transitions
Multiple audio tracks
Secured log-on
Frame accurate timeline for fine cut editing
Logging / meta-data annotation assigns text to portions of video (usable by Clesh and web search engines)
Storyboard assembles rough cuts using drag-and-drop
Import, host, organise and search for media (DV tape and various video, audio, and still image formats)
Publish content to in formats such as podcast, MPEG-2, web (Java Applet), Flash, Ogg, HTML5 and JPEG
Chatrooms to talk to oth |
https://en.wikipedia.org/wiki/Van%20der%20Meer%20formula | The Van der Meer formula is a formula for calculating the required stone weight for armourstone under the influence of (wind) waves. This is necessary for the design of breakwaters and shoreline protection. Around 1985 it was found that the Hudson formula in use at that time had considerable limitations (only valid for permeable breakwaters and steep (storm) waves). That is why the Dutch government agency Rijkswaterstaat commissioned Deltares to start research for a more complete formula. This research, conducted by Jentsje van der Meer, resulted in the Van der Meer formula in 1988, as described in his dissertation.
This formula reads
and
In this formula:
Hs = Significant wave height at the toe of the construction
Δ = relative density of the stone (= (ρs -ρw)/ρw) where ρs is the density of the stone and ρw is the density of the water
dn50 = nominal stone diameter
α = breakwater slope
P = notional permeability
S = Damage number
N = number of waves in the storm
ξm = the Iribarren number calculated with the Tm
For design purposes, for the coefficient cp the value of 5,2 and for cs the value 0,87 is recommended.
The value of P can be read from attached graph. Until now, there is no good method for determining P different than with accompanying pictures. Research is under way to try to determine the value of P using calculation models that can simulate the water movement in the breakwater (OpenFOAM models).
The value of the damage number S is defined as
where A is the area of the erosion area. Permissible values for ''S are: |
https://en.wikipedia.org/wiki/Adenitis | Adenitis is a general term for an inflammation of a gland. Often it is used to refer to lymphadenitis which is the inflammation of a lymph node.
Classification
Lymph node adenitis
Lymph adenitis or lymph node adenitis is caused by infection in lymph nodes. The infected lymph nodes typically become enlarged, warm and tender. A swelling of lymph nodes due to growth of lymph cells is called lymphadenopathy. Types include:
Neck
Cervical adenitis is an inflammation of a lymph node in the neck.
Tuberculous adenitis (scrofula) is a tuberculous infection of the skin of the neck caused by Mycobacterium tuberculosis. Non-tuberculous adenitis can also be caused by Mycobacterium scrofulaceum or Mycobacterium avium.
Abdomen
Mesenteric adenitis is an inflammation of the mesenteric lymph nodes in the abdomen. It can be caused by the bacterium Yersinia enterocolitica. If it occurs in the right lower quadrant, it can be mistaken for acute appendicitis, often preceded by a sore throat. Clinical manifestations may include fever, right lower quadrant abdominal pain, nausea, and vomiting. Most often occurs in children age 5–14.
Other
Sebaceous adenitis is an inflammation of the sebaceous glands
in the skin. These glands normally produce sebum (skin oil, a lipid-rich secretion) which prevents drying of the skin. |
https://en.wikipedia.org/wiki/German%20locomotive%20classification | The different railway companies in Germany have used various schemes to classify their rolling stock.
From the beginning
As widely known the first few locomotives had names. The first locomotive in public service in Germany from 1835 was named Adler. The first railway lines were built by privately owned companies. That changed later when many railway companies were taken over or founded by the respective German states such as Prussia, Bavaria, etc.
Different numbering schemes prior to 1924
The fast-growing number of locomotives made a numbering scheme inevitable. Most of the various state-owned German railway companies (called Länderbahnen in German) developed their own schemes, e. g. the Prussian state railways (preußische Staatseisenbahnen sometimes erroneously referred to as the Königlich Preussische Eisenbahn-Verwaltung or KPEV) introduced P for passenger train locomotives (the P 8 was one of the most important locomotive types with a total of over 3,000 units built), S for Schnellzug (express train) locomotives (e. g. the famous S 10), G for Güterzug (freight train) locomotives and T for Tenderlokomotive (tank locomotive). Basically the numbers were used continuously. As the Prussians also standardised technical standards, some of the smaller companies also used the Prussian numbering scheme or a similar one.
Bavaria's state-owned railway chose a different way: They also used P, S, or G to indicate the train type, but combined with the numbers of driving axles and of the axles in total, separated by a slash (similar to the Swiss system). E. g., the famous S 3/6 was a 2'C1' or 4-6-2 Pacific, meaning that of a total of 6 axles, 3 were driving axles.
These various state-owned companies and thus their numbering schemes were retained after German unification in 1871 and kept until well after World War I.
The first uniform scheme
The Deutsche Reichsbahn-Gesellschaft DRG was founded in 1924 by the amalgamation of the various state-owned Länderbahnen. One of its |
https://en.wikipedia.org/wiki/Hypercycle%20%28geometry%29 | In hyperbolic geometry, a hypercycle, hypercircle or equidistant curve is a curve whose points have the same orthogonal distance from a given straight line (its axis).
Given a straight line and a point not on , one can construct a hypercycle by taking all points on the same side of as , with perpendicular distance to equal to that of . The line is called the axis, center, or base line of the hypercycle. The lines perpendicular to , which are also perpendicular to the hypercycle, are called the normals of the hypercycle. The segments of the normals between and the hypercycle are called the radii. Their common length is called the distance or radius of the hypercycle.
The hypercycles through a given point that share a tangent through that point converge towards a horocycle as their distances go towards infinity.
Properties similar to those of Euclidean lines
Hypercycles in hyperbolic geometry have some properties similar to those of lines in Euclidean geometry:
In a plane, given a line and a point not on it, there is only one hypercycle of that of the given line (compare with Playfair's axiom for Euclidean geometry).
No three points of a hypercycle are on a circle.
A hypercycle is symmetrical to each line perpendicular to it. (Reflecting a hypercycle in a line perpendicular to the hypercycle results in the same hypercycle.)
Properties similar to those of Euclidean circles
Hypercycles in hyperbolic geometry have some properties similar to those of circles in Euclidean geometry:
A line perpendicular to a chord of a hypercycle at its midpoint is a radius and it bisects the arc subtended by the chord.
Let AB be the chord and M its middle point.
By symmetry the line R through M perpendicular to AB must be orthogonal to the axis L.
Therefore R is a radius.
Also by symmetry, R will bisect the arc AB.
The axis and distance of a hypercycle are uniquely determined.
Let us assume that a hypercycle C has two different axes L1 and L2.
Using the previous p |
https://en.wikipedia.org/wiki/List%20of%20search%20appliance%20vendors | A search appliance is a type of computer which is attached to a corporate network for the purpose of indexing the content shared across that network in a way that is similar to a web search engine. It may be made accessible through a public web interface or restricted to users of that network. A search appliance is usually made up of: a gathering component, a standardizing component, a data storage area, a search component, a user interface component, and a management interface component.
Vendors of search appliances
Fabasoft
Google
InfoLibrarian Search Appliance™
Maxxcat
Searchdaimon
Thunderstone
Former/defunct vendors of search appliances
Black Tulip Systems
Google Search Appliance
Index Engines
Munax
Perfect Search Appliance |
https://en.wikipedia.org/wiki/Quasicircle | In mathematics, a quasicircle is a Jordan curve in the complex plane that is the image of a circle under a quasiconformal mapping of the plane onto itself. Originally introduced independently by and , in the older literature (in German) they were referred to as quasiconformal curves, a terminology which also applied to arcs. In complex analysis and geometric function theory, quasicircles play a fundamental role in the description of the universal Teichmüller space, through quasisymmetric homeomorphisms of the circle. Quasicircles also play an important role in complex dynamical systems.
Definitions
A quasicircle is defined as the image of a circle under a quasiconformal mapping of the extended complex plane. It is called a K-quasicircle if the quasiconformal mapping has dilatation K. The definition of quasicircle generalizes the characterization of a Jordan curve as the image of a circle under a homeomorphism of the plane. In particular a quasicircle is a Jordan curve. The interior of a quasicircle is called a quasidisk.
As shown in , where the older term "quasiconformal curve" is used, if a Jordan curve is the image of a circle under a quasiconformal map in a neighbourhood of the curve, then it is also the image of a circle under a quasiconformal mapping of the extended plane and thus a quasicircle. The same is true for "quasiconformal arcs" which can be defined as quasiconformal images of a circular arc either in an open set or equivalently in the extended plane.
Geometric characterizations
gave a geometric characterization of quasicircles as those Jordan curves for which the absolute value of the cross-ratio of any four points, taken in cyclic order, is bounded below by a positive constant.
Ahlfors also proved that quasicircles can be characterized in terms of a reverse triangle inequality for three points: there should be a constant C such that if two points z1 and z2 are chosen on the curve and z3 lies on the shorter of the resulting arcs, then
This pro |
https://en.wikipedia.org/wiki/Olfactometer | An olfactometer is an instrument used to detect and measure odor dilution. Olfactometers are used in conjunction with human subjects in laboratory settings, most often in market research, to quantify and qualify human olfaction. Olfactometers are used to gauge the odor detection threshold of substances. To measure intensity, olfactometers introduce an odorous gas as a baseline against which other odors are compared.
Many scientists use the term "olfactometer" to refer to a device used to study insect behavior in presence of an olfactory stimulus. It consists of a tube with a bifurcation (with "T" or "Y" shape) where an insect walks and decides between two choices, usually clean air versus air carrying an odor. This is why this device is also called dual choice olfactometer.
Alternatively, an olfactometer is a device used for producing aromas in a precise and controlled manner.
Flow-olfactometer
Description
According to Lindstrom at al, continuous flow olfactometers enable very fast onset and offset timing, thereby creating a nice, square-shaped stimulus presentation. In these designs, air flows continuously through or over the odor source and is then transported via tubing to the subject. Vacuum pressure plays an important role in a continuous flow olfactometer, where it is utilized both to switch between odorized air flow and control flow and to evacuate odors, often just below the subject’s nose. The
How a flow-olfactometer works
A flow-olfactometer produces a constant heated and humidified flow of pure air. This air flow runs continuously to the subjects nose. For the length of the stimulus pulse the continuous air flow is replaced by a block of odorized air.
Dynamic dilution olfactometer
The new generations of dynamic dilution olfactometers quantify odors using a panel and can allow different complementary techniques: odor concentration and odor threshold determination, odor suprathreshold determination with comparison to a reference gas, hedonic scale |
https://en.wikipedia.org/wiki/Vermiform | Vermiform (ˈvərməˌfôrm) describes something shaped like a worm. The expression is often employed in biology and anatomy to describe usually soft body parts or animals that are more or less tubular or cylindrical. The word root is Latin, vermes (worms) and formes (shaped). A well known example is the vermiform appendix, a small, blind section of the gut in humans and a number of other mammals.
A number of soft-bodied animal phyla are typically described as vermiform. The better-known ones are undoubtedly the annelids (earthworm and relatives) and the roundworms (a very common, mainly parasitic group), but a number of less-well-known phyla answer to the same description. Examples range from the minute parasitic mesozoans to the larger-bodied free-living phyla like ribbon worms, peanut worms, and priapulids. |
https://en.wikipedia.org/wiki/Harry%20Leinweber | Harry C. Leinweber (January 6, 1907 – March 19, 1992) was a politician from Alberta, Canada. He served in the Legislative Assembly of Alberta from 1961 to 1971 as a member of the Social Credit Party.
Political career
Leinweber served as a municipal Alderman for the city of Medicine Hat from 1944 to 1950. He ran for mayor twice but was unsuccessful.
Leinweber first ran for a seat to the Alberta legislature in a by-election held on January 19, 1961, in the electoral district of Medicine Hat. He defeated three other candidates with just under half the popular vote to hold the district for Social Credit.
In the 1963 general election Leinweber was re-elected with over 51% of the popular vote over three other candidates.
In the 1967 general election Leinweber won the district with just 40% of the popular vote over future MLA Jim Horsman. He retired from the Legislature at dissolution in 1971. |
https://en.wikipedia.org/wiki/National%20Foods%20Limited | National Foods Limited () is a Pakistani multinational food products company founded in 1970, which started out as a spice company, and is based in Karachi, Pakistan. It is a major food products company in Pakistan.
History
The company was incorporated in Pakistan on 19 February 1970 as a private limited company under the Indian Companies Act, 1913 and subsequently converted into a public limited company under the Companies Ordinance, 1984 by a special resolution passed in the extraordinary general meeting held on March 30, 1988. The company is principally engaged in the manufacture and sale of convenience-based food products. The registered office of the company is situated at 12 / CL - 6, Claremont Road, Civil Lines, Karachi.
In 1988, National Foods became the certified vendor of McCormick, United States. In the same year, National Foods, then a Private Limited company was converted into a Public Limited company, traded on all the three stock exchanges of Pakistan. On 11 January 2016, all three former city stock exchanges in Pakistan merged to form Pakistan Stock Exchange.
In 2013, as a company National Foods Limited (Pakistan) was listed on the Forbes List of Asia's 200 Best Under A Billion (2013).
In 2017, National Foods Limited acquired a controlling interest in Canadian company A1 Cash & Carry to further expand its operations across the globe. A1 Cash & Carry is a wholesale distributor of foodservice products, disposables, and sanitation/janitorial products in Canada. This company is partially owned by a Canadian-based Pakistani businessman Amjad Pervaiz.
With a range of over 250 food products in over 10 major categories, National Foods is one of the prominent food companies in Pakistan.
Subsidiaries
National Foods DMCC (Dubai)
National Foods Pakistan (UK) Limited
National Epicure Inc, (Canada)
Products
Spices, pickles, tomato ketchup, jams, jellies, sauces, cooking pastes, fruit juices, fruit drinks
Biryanis, curries, barbeque items and kababs ( |
https://en.wikipedia.org/wiki/International%20Symposium%20on%20Power%20Semiconductor%20Devices%20and%20ICs | ISPSD (International Symposium on Power Semiconductor Devices and ICs) is an annual conference established in 1988 by the Institute of Electrical and Electronics Engineers (IEEE) on a wide range of power technologies. Host to over 500 experts from across the world, ISPSD is the premier forum for technical discussions in all areas of power semiconductor devices and power integrated circuits, recently focusing on gallium nitride and silicon carbide devices.
The conferences are held in Asia, North America, and Europe on a rotating basis. ISPSD celebrated its 30th anniversary in Chicago, United States from May 13 to 17, 2018. The previous year's conference was held in Sapporo, Japan from May 28 to June 1, 2017. ISPSD 2016 was held in Prague, Czech Republic in June 2016. ISPSD 2019 was held in May 2019 in Shanghai, China. |
https://en.wikipedia.org/wiki/Write-ahead%20logging | In computer science, write-ahead logging (WAL) is a family of techniques for providing atomicity and durability (two of the ACID properties) in database systems.
It can be seen as an implementation of the "Event Sourcing" architecture, in which the state of a system is the result of the evolution of incoming events from an initial state.
A write ahead log is an append-only auxiliary disk-resident structure used for crash and transaction recovery. The changes are first recorded in the log, which must be written to stable storage, before the changes are written to the database.
The main functionality of a write-ahead log can be summarized as:
Allow the page cache to buffer updates to disk-resident pages while ensuring durability semantics in the larger context of a database system.
Persist all operations on disk until the cached copies of pages affected by these operations are synchronized on disk. Every operation that modifies the database state has to be logged on disk before the contents on the associated pages can be modified
Allow lost in-memory changes to be reconstructed from the operation log in case of a crash.
In a system using WAL, all modifications are written to a log before they are applied. Usually both redo and undo information is stored in the log.
The purpose of this can be illustrated by an example. Imagine a program that is in the middle of performing some operation when the machine it is running on loses power. Upon restart, that program might need to know whether the operation it was performing succeeded, succeeded partially, or failed. If a write-ahead log is used, the program can check this log and compare what it was supposed to be doing when it unexpectedly lost power to what was actually done. On the basis of this comparison, the program could decide to undo what it had started, complete what it had started, or keep things as they are.
After a certain amount of operations, the program should perform a checkpoint, writing all the cha |
https://en.wikipedia.org/wiki/Merit%20Network | Merit Network, Inc., is a nonprofit member-governed organization providing high-performance computer networking and related services to educational, government, health care, and nonprofit organizations, primarily in Michigan. Created in 1966, Merit operates the longest running regional computer network in the United States.
Organization
Created in 1966 as the Michigan Educational Research Information Triad by Michigan State University (MSU), the University of Michigan (U-M), and Wayne State University (WSU), Merit was created to investigate resource sharing by connecting the mainframe computers at these three Michigan public research universities. Merit's initial three node packet-switched computer network was operational in October 1972 using custom hardware based on DEC PDP-11 minicomputers and software developed by the Merit staff and the staffs at the three universities.
Over the next dozen years the initial network grew as new services such as dial-in terminal support, remote job submission, remote printing, and file transfer were added; as gateways to the national and international Tymnet, Telenet, and Datapac networks were established, as support for the X.25 and TCP/IP protocols was added; as additional computers such as WSU's MVS system and the UM's electrical engineering's VAX running UNIX were attached; and as new universities became Merit members.
Merit's involvement in national networking activities started in the mid-1980s with connections to the national supercomputing centers and work on the 56 kbit/s National Science Foundation Network (NSFNET), the forerunner of today's Internet. From 1987 until April 1995, Merit re-engineered and managed the NSFNET backbone service.
MichNet, Merit's regional network in Michigan was attached to NSFNET and in the early 1990s Merit began extending "the Internet" throughout Michigan, offering both direct connect and dial-in services, and upgrading the statewide network from 56 kbit/s to 1.5 Mbit/s, and on to 45, |
https://en.wikipedia.org/wiki/RNA%20silencing | RNA silencing or RNA interference refers to a family of gene silencing effects by which gene expression is negatively regulated by non-coding RNAs such as microRNAs. RNA silencing may also be defined as sequence-specific regulation of gene expression triggered by double-stranded RNA (dsRNA). RNA silencing mechanisms are conserved among most eukaryotes. The most common and well-studied example is RNA interference (RNAi), in which endogenously expressed microRNA (miRNA) or exogenously derived small interfering RNA (siRNA) induces the degradation of complementary messenger RNA. Other classes of small RNA have been identified, including piwi-interacting RNA (piRNA) and its subspecies repeat associated small interfering RNA (rasiRNA).
Background
RNA silencing describes several mechanistically related pathways which are involved in controlling and regulating gene expression. RNA silencing pathways are associated with the regulatory activity of small non-coding RNAs (approximately 20–30 nucleotides in length) that function as factors involved in inactivating homologous sequences, promoting endonuclease activity, translational arrest, and/or chromatic or DNA modification. In the context in which the phenomenon was first studied, small RNA was found to play an important role in defending plants against viruses. For example, these studies demonstrated that enzymes detect double-stranded RNA (dsRNA) not normally found in cells and digest it into small pieces that are not able to cause disease.
While some functions of RNA silencing and its machinery are understood, many are not. For example, RNA silencing has been shown to be important in the regulation of development and in the control of transposition events. RNA silencing has been shown to play a role in antiviral protection in plants as well as insects. Also in yeast, RNA silencing has been shown to maintain heterochromatin structure. However, the varied and nuanced role of RNA silencing in the regulation of gene express |
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