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https://en.wikipedia.org/wiki/International%20Society%20for%20Augmentative%20and%20Alternative%20Communication
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The International Society for Augmentative and Alternative Communication (ISAAC) was founded in May 1983 in East Lansing, Michigan, United States. Its stated purpose is to improve the communication abilities and quality of life of individuals with complex communication needs who use augmentative and alternative communication (AAC). ISAAC provides information about AAC services, policies and activities around the world thorough various publications and their website. The society publishes a journal and various other publications, organizes biennial conferences, promotes research on AAC use and AAC development as well as implements various projects.
Purpose
ISAAC works to promote augmentative and alternative communication as a known and valued way of communicating worldwide. The society's vision "is that AAC will be recognized, valued and used throughout the world" and the society's mission "is to promote the best possible communication for people with complex needs". The society encourages research and scholarship as well as works to improve service delivery.
Structure
ISAAC has more than 3700 members from over 60 different countries. Members include professionals, AAC users and their families and friends. The society is recognized as a nongovernmental organization in consultative status with the United Nations Economic and Social Council.
National chapters of ISAAC are located in many different countries. Chapters exist in Australia, Canada, Denmark, Finland, French-speaking countries and regions, German-speaking countries and regions, India, Ireland, Israel, Italy, Netherlands and Flanders, Norway, Sweden, United Kingdom and United States of America. Each chapter has a wide variety of members. For example, members of the Communication Matters, UK chapter, include: AAC users, families of AAC users, professionals working with AAC users, researchers and academics.
Activities
ISAAC has publications including Augmentative and Alternative Communication (AAC), whic
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https://en.wikipedia.org/wiki/Pardaxin
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Pardaxin is a peptide produced by the Red Sea sole (P4, P5) and the Pacific Peacock sole (P1, P2, P3) that is used as a shark repellent. It causes lysis of mammalian and bacterial cells, similar to melittin.
Synthesis
In the lab, pardaxin is synthesized using an automated peptide synthesizer. Alternatively, the secretions of the Red Sea sole can be collected and purified.
Functions
Antibacterial peptide
Pardaxin has a helix-hinge-helix structure. This structure is common in peptides that act selectively on bacterial membranes and cytotoxic peptides that lyse mammalian and bacterial cells. Pardaxin shows a significantly lower hemolytic activity towards human red blood cells compared to melittin. The C-terminal tail of pardaxin is responsible for this non-selective activity against the erythrocytes and bacteria. The amphiphilic C-terminal helix is the ion-channel lining segment of the peptide. The N-terminal α-helix is important for the insertion of the peptide to the lipid bilayer of the cell.
The mechanism of pardaxin is dependent on the membrane composition. Pardaxin significantly disrupts lipid bilayers composed of zwitterionic lipids, especially those composed of 1-palmitoyl-2-oleoyl-phosphatidylcholine (POPC). This suggests a carpet mechanism for cell lysis. The carpet mechanism is when a high density of peptides accumulates on the target membrane surface. The phospholipid displacement changes in fluidity, and the cellular contents leak out. The presence of anionic lipids or cholesterol was found to reduce the peptide's ability to disrupt bilayers.
Shark repellent
P. marmoratas and P. pavoninus release pardaxin when threatened by sharks. Pardaxin targets the gills and pharyngeal cavity of the sharks. It results in severe struggling, mouth paralysis, and temporary increase of urea leakage in the gills. This distress is caused by the attack of the cellular membrane of the gills, which causes a large influx of salt ions. Research into creating a commercial sha
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https://en.wikipedia.org/wiki/Opposite%20category
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In category theory, a branch of mathematics, the opposite category or dual category Cop of a given category C is formed by reversing the morphisms, i.e. interchanging the source and target of each morphism. Doing the reversal twice yields the original category, so the opposite of an opposite category is the original category itself. In symbols, .
Examples
An example comes from reversing the direction of inequalities in a partial order. So if X is a set and ≤ a partial order relation, we can define a new partial order relation ≤op by
x ≤op y if and only if y ≤ x.
The new order is commonly called dual order of ≤, and is mostly denoted by ≥. Therefore, duality plays an important role in order theory and every purely order theoretic concept has a dual. For example, there are opposite pairs child/parent, descendant/ancestor, infimum/supremum, down-set/up-set, ideal/filter etc. This order theoretic duality is in turn a special case of the construction of opposite categories as every ordered set can be understood as a category.
Given a semigroup (S, ·), one usually defines the opposite semigroup as (S, ·)op = (S, *) where x*y ≔ y·x for all x,y in S. So also for semigroups there is a strong duality principle. Clearly, the same construction works for groups, as well, and is known in ring theory, too, where it is applied to the multiplicative semigroup of the ring to give the opposite ring. Again this process can be described by completing a semigroup to a monoid, taking the corresponding opposite category, and then possibly removing the unit from that monoid.
The category of Boolean algebras and Boolean homomorphisms is equivalent to the opposite of the category of Stone spaces and continuous functions.
The category of affine schemes is equivalent to the opposite of the category of commutative rings.
The Pontryagin duality restricts to an equivalence between the category of compact Hausdorff abelian topological groups and the opposite of the category of (discrete)
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https://en.wikipedia.org/wiki/Focus%20stacking
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Focus stacking (also known as focal plane merging and z-stacking or focus blending) is a digital image processing technique which combines multiple images taken at different focus distances to give a resulting image with a greater depth of field (DOF) than any of the individual source images. Focus stacking can be used in any situation where individual images have a very shallow depth of field; macro photography and optical microscopy are two typical examples. Focus stacking can also be useful in landscape photography.
Focus stacking offers flexibility: since it is a computational technique, images with several different depths of field can be generated in post-processing and compared for best artistic merit or scientific clarity. Focus stacking also allows generation of images physically impossible with normal imaging equipment; images with nonplanar focus regions can be generated. Alternative techniques for generating images with increased or flexible depth of field include wavefront coding, light-field cameras and tilt.
Technique
The starting point for focus stacking is a series of images captured at different focus distances; in each image different areas of the sample will be in focus. While none of these images has the sample entirely in focus they collectively contain all the data required to generate an image which has all parts of the sample in focus. In-focus regions of each image may be detected automatically, for example via edge detection or Fourier analysis, or selected manually. The in-focus patches are then blended together to generate the final image.
This processing is also called z-stacking, focal plane merging (or in French).
In photography
Getting sufficient depth of field can be particularly challenging in macro photography, because depth of field is smaller (shallower) for objects nearer the camera, so if a small object fills the frame, it is often so close that its entire depth cannot be in focus at once. Depth of field is normally incre
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https://en.wikipedia.org/wiki/Gaussian%20quadrature
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In numerical analysis, an -point Gaussian quadrature rule, named after Carl Friedrich Gauss, is a quadrature rule constructed to yield an exact result for polynomials of degree or less by a suitable choice of the nodes and weights for .
The modern formulation using orthogonal polynomials was developed by Carl Gustav Jacobi in 1826. The most common domain of integration for such a rule is taken as , so the rule is stated as
which is exact for polynomials of degree or less. This exact rule is known as the Gauss-Legendre quadrature rule. The quadrature rule will only be an accurate approximation to the integral above if is well-approximated by a polynomial of degree or less on .
The Gauss-Legendre quadrature rule is not typically used for integrable functions with endpoint singularities. Instead, if the integrand can be written as
where is well-approximated by a low-degree polynomial, then alternative nodes and weights will usually give more accurate quadrature rules. These are known as Gauss-Jacobi quadrature rules, i.e.,
Common weights include (Chebyshev–Gauss) and . One may also want to integrate over semi-infinite (Gauss-Laguerre quadrature) and infinite intervals (Gauss–Hermite quadrature).
It can be shown (see Press, et al., or Stoer and Bulirsch) that the quadrature nodes are the roots of a polynomial belonging to a class of orthogonal polynomials (the class orthogonal with respect to a weighted inner-product). This is a key observation for computing Gauss quadrature nodes and weights.
Gauss–Legendre quadrature
For the simplest integration problem stated above, i.e., is well-approximated by polynomials on , the associated orthogonal polynomials are Legendre polynomials, denoted by . With the -th polynomial normalized to give , the -th Gauss node, , is the -th root of and the weights are given by the formula
Some low-order quadrature rules are tabulated below (over interval , see the section below for other intervals).
Change of interval
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https://en.wikipedia.org/wiki/Misha%20Verbitsky
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Misha Verbitsky (, born June 20, 1969, in Moscow) is a Russian mathematician. He works at the Instituto Nacional de Matemática Pura e Aplicada in Rio de Janeiro. He is primarily known to the general public as a controversial critic, political activist and independent music publisher.
Scientific activities
Verbitsky graduated from a Math class at the Moscow State School 57 in 1986, and has been active in mathematics since then. His principal area of interest in mathematics is differential geometry, especially geometry of hyperkähler manifolds and locally conformally Kähler manifolds. He proved an analogue of the global Torelli theorem for hyperkähler manifolds and the mirror conjecture in hyperkähler case. He also contributed to the theory of Hodge structures. His PhD thesis, titled Cohomology of compact Hyperkaehler Manifolds, was defended in 1995 at Harvard University under the supervision of David Kazhdan. He has held different positions, most prominently at the Independent University of Moscow (since 1996), the University of Glasgow (2002–2007), and the HSE Faculty of Mathematics (since 2010). He currently works at IMPA in Rio de Janeiro.
Lenin
Verbitsky's webzine :LENIN:, started around 1997, is one of the oldest Russian online projects and has been hugely influential in the shaping of Russian counter-culture. It was the first website in Russian to openly discuss topics considered taboo at the time, such as pornography and Right-wing extremism, and to create a milieu for the emerging counter-culture aesthetic. The site also contains the largest single collection of rare underground music from the ex-USSR and contemporary Russia.
Western counter-culture
While studying mathematics at Harvard University in the early 90s, Verbitsky was heavily influenced by Western counter-culture, especially Thelema and industrial music, and was the first to introduce these concepts to post-Soviet Russia via his webzine. At the same time, Verbitsky developed his political views
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https://en.wikipedia.org/wiki/Lillian%20Rosanoff%20Lieber
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Lillian Rosanoff Lieber (July 26, 1886 in Nicolaiev, Russian Empire – July 11, 1986 in Queens, New York) was a Russian-American mathematician and popular author. She often teamed up with her illustrator husband, Hugh Gray Lieber, to produce works.
Life and career
Early life and education
Lieber was one of four children of Abraham H. and Clara (Bercinskaya) Rosanoff. Her brothers were Denver publisher Joseph Rosenberg, psychiatrist Aaron Rosanoff, and chemist Martin André Rosanoff. Aaron and Martin changed their names to sound more Russian, less Jewish. Lieber moved to the US with her family in 1891. She received her A.B. from Barnard College in 1908, her M.A. from Columbia University in 1911, and her Ph.D. (in chemistry) from Clark University in 1914, under Martin's direction; at Clark, Solomon Lefschetz was a classmate. She married Hugh Gray Lieber on October 27, 1926.
Career
After teaching at Hunter College from 1908 to 1910, and in the New York City high school system (1910–1912, 1914–1915), she became a Research Fellow at Bryn Mawr College from 1915 to 1917; she then went on to teach at Wells College from 1917 to 1918 as Instructor of Physics (also acting as head of the physics department), and at the Connecticut College for Women (1918 to 1920). She joined the mathematics department at Long Island University (LIU) in Brooklyn, New York (LIU Brooklyn) in 1934, became department chair in 1945 (taking over from Hugh when he became Professor, and Chair, of Art at LIU ), and was made a full professor in 1947, until her retirement in 1954; she was appointed director of LIU's Galois Institute of Mathematics (later the Galois Institute of Mathematics and Art) (named for Évariste Galois) in 1934. Over her career she published some 17 books, which were written in a unique, free-verse style and illustrated with whimsical line drawings by her husband. Her highly accessible writings were praised by no less than Albert Einstein, Cassius Jackson Keyser, Eric Temple Bell,
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https://en.wikipedia.org/wiki/Luchacovirus
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Luchacovirus is a subgenus of viruses in the genus Alphacoronavirus, consisting of a single species, Lucheng Rn rat coronavirus.
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https://en.wikipedia.org/wiki/Plane%20%28mathematics%29
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In mathematics, a plane is a two-dimensional space or flat surface that extends indefinitely.
A plane is the two-dimensional analogue of a point (zero dimensions), a line (one dimension) and three-dimensional space.
When working exclusively in two-dimensional Euclidean space, the definite article is used, so the Euclidean plane refers to the whole space.
Many fundamental tasks in mathematics, geometry, trigonometry, graph theory, and graphing are performed in a two-dimensional or planar space.
Euclidean plane
Embedding in three-dimensional space
Elliptic plane
Projective plane
Further generalizations
In addition to its familiar geometric structure, with isomorphisms that are isometries with respect to the usual inner product, the plane may be viewed at various other levels of abstraction. Each level of abstraction corresponds to a specific category.
At one extreme, all geometrical and metric concepts may be dropped to leave the topological plane, which may be thought of as an idealized homotopically trivial infinite rubber sheet, which retains a notion of proximity, but has no distances. The topological plane has a concept of a linear path, but no concept of a straight line. The topological plane, or its equivalent the open disc, is the basic topological neighborhood used to construct surfaces (or 2-manifolds) classified in low-dimensional topology. Isomorphisms of the topological plane are all continuous bijections. The topological plane is the natural context for the branch of graph theory that deals with planar graphs, and results such as the four color theorem.
The plane may also be viewed as an affine space, whose isomorphisms are combinations of translations and non-singular linear maps. From this viewpoint there are no distances, but collinearity and ratios of distances on any line are preserved.
Differential geometry views a plane as a 2-dimensional real manifold, a topological plane which is provided with a differential structure. Again in this
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https://en.wikipedia.org/wiki/Visibility%20graph%20analysis
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In architecture, visibility graph analysis (VGA) is a method of analysing the inter-visibility connections within buildings or urban networks. Visibility graph analysis was developed from the architectural theory of space syntax by Turner et al. (2001), and is applied through the construction of a visibility graph within the open space of a plan.
Visibility graph analysis uses various measures from the theory of small-world networks and centrality in network theory in order to assess perceptual qualities of space and the possible usage of it.
Visibility graph analysis was firstly implemented in Turner's Depthmap software and is now widely used by both academics and practitioners through the open source and multi-platform depthmapX developed by Tasos Varoudis.
Another opensource and multi-platform software that implements visibility graphs is topologicpy developed by Wassim Jabi.
See also
Fuzzy architectural spatial analysis
Isovist
Spatial network analysis software
Viewshed analysis
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https://en.wikipedia.org/wiki/IEEE%20Fourier%20Award%20for%20Signal%20Processing
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The IEEE Fourier Award for Signal Processing is a Technical Field Award that is given by the Institute of Electrical and Electronics Engineers. This award is presented for contributions in the field of signal processing.
The award is named after Joseph Fourier, a French mathematician and physicist who is noted for the representation of periodic signals as linear superpositions of sine-wave basis functions known as the Fourier series, and applications of the Fourier Series to the analysis of vibration and heat transfer. The Fourier transform, which is widely used throughout electrical engineering and in particular signal processing, image processing, and communication theory, is also named in his honor.
The IEEE Fourier Award for Signal Processing may be presented to an individual or team of up to three people.
Recipients of the IEEE Fourier Award for Signal Processing receive a bronze medal, certificate, and honorarium. The Fourier Award is presented annually at the IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP) in the Spring.
Recipients
2024: Stéphane Mallat
2023: Rabab Ward
2022: Ali H. Sayed
2021: K.J. Ray Liu
2020: Alfred O. Hero III
2019: Alan Conrad Bovik
2018: Peter Stoica
2017: Russell Mersereau
2016: Bede Liu
2015: Georgios B. Giannakis
See also
List of engineering awards
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https://en.wikipedia.org/wiki/Ayodele%20Awojobi
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Ayodele Oluwatumininu Awojobi (12 March 1937 – 23 September 1984), also known by the nicknames "Dead Easy",
"The Akoka Giant", and "Macbeth", was a Nigerian academic, author, inventor, social crusader and activist.
He was considered a scholarly genius by his teachers and peers alike.
His research papers, particularly in the field of vibration, are still cited by international research fellows in Engineering as lately as the year 2020, and are archived by such publishers as the Royal Society.
Early life
Born in Oshodi, Lagos State, Awojobi's father, Chief Daniel Adekoya Awojobi, was a stationmaster at the Nigerian Railway Corporation who hailed from Ikorodu in Lagos State. His mother, Comfort Bamidele Awojobi (née Adetunji), was a petty trader who hailed from Modakeke, Ile-Ife, Osun State.
Between 1942 and 1947, he attended St. Peter's Primary School, Faji, Lagos.
It was while at his secondary school, the CMS Grammar School, Lagos, that his academic traits began to manifest. Not only was he seen to be gifted in mathematics and the sciences, he was comfortable also in the arts, becoming a member of the school's literary and debating society. It was during this period that he earned the nickname, "Macbeth": William Shakespeare's famous play, Macbeth, was to be staged in the school. The lead actor took ill a week before, and so Ayodele was called upon to play the lead role in his stead. It is said that not only did Ayodele master his lines as lead actor, but also the entire play, such that he was able to prompt the cast whenever they forgot their lines.
Academic achievements
Ayodele Oluwatumininu Awojobi was a straight-A's secondary school student, while at the CMS Grammar school, passing his West African School Certificate examinations with a record eight distinctions in 1955.
He proceeded to the Nigerian College of Arts, Science and Technology, Ibadan, for his General Certificate of Examinations, GCE (Advanced Level), where in 1958 he sat for, and obtained distinc
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https://en.wikipedia.org/wiki/Hormogonium
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Hormogonia are motile filaments of cells formed by some cyanobacteria in the order Nostocales and Stigonematales. They are formed during vegetative reproduction in unicellular, filamentous cyanobacteria, and some may contain heterocysts and akinetes.
Cyanobacteria differentiate into hormogonia when exposed to an environmental stress or when placed in new media.
Hormogonium differentiation is crucial for the development of nitrogen-fixing plant cyanobacteria symbioses, in particular that between cyanobacteria of the genus Nostoc and their hosts. In response to a hormogonium-inducing factor (HIF) secreted by plant hosts, cyanobacterial symbionts differentiate into hormogonia and then dedifferentiate back into vegetative cells after about 96 hours. Hopefully, they have managed to reach the plant host by this time. The bacteria then differentiate specialized nitrogen-fixing cells called heterocysts and enter into a working symbiosis with the plant.
Depending on species, Hormogonia can be many hundreds of micrometers in length and can travel as fast as 11 μm/s. They move via gliding motility, requiring a wettable surface or a viscous substrate, such as agar for motion.
Cell anatomy
Cyanobacteria
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https://en.wikipedia.org/wiki/Simplicial%20volume
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In the mathematical field of geometric topology, the simplicial volume (also called Gromov norm) is a certain measure of the topological complexity of a manifold. More generally, the simplicial norm measures the complexity of homology classes.
Given a closed and oriented manifold, one defines the simplicial norm by minimizing the sum of the absolute values of the coefficients over all singular chains homologous to a given cycle. The simplicial volume is the simplicial norm of the fundamental class.
It is named after Mikhail Gromov, who introduced it in 1982. With William Thurston, he proved that the simplicial volume of a finite volume hyperbolic manifold is proportional to the hyperbolic volume.
The simplicial volume is equal to twice the Thurston norm
Thurston also used the simplicial volume to prove that hyperbolic volume decreases under hyperbolic Dehn surgery.
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https://en.wikipedia.org/wiki/European%20Processor%20Initiative
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The (EPI) is a European processor project to design and build a new family of European low-power processors for supercomputers, Big Data, automotive, and offering high performance on traditional HPC applications and emerging applications such as on machine learning. It is led by a consortium of European companies and universities. The project is divided in multiple phases funded under Specific Grant Agreements. The first grant agreement is implemented under the European Commission program Horizon 2020 (FPA: 800928) in the December 2018 to November 2021 time span. The second agreement will be implemented afterwards under the EuroHPC Joint Undertaking which issued a call answered to in January 2021 by the same consortium (H2020-JTI-EuroHPC-2020-02 FPA in EPI (phase II)).
The processor is a SoC, of RISC technology, implementing microprocessor cores of ARM architecture and accelerators, specialised in matrix calculations and deep learning for artificial intelligence. The processor is designed to be integrated in an exascale supercomputer, but also to be implemented in cars.
Objectives
The aim of the EPI project is to design and build a high-performance, low-power processor, implementing vector instructions and specific accelerators, such as accelerators for AI, with high-bandwidth memory access. The design will be based on the results obtained through an intensive use of simulation, the development of a complete software stack and the use of advanced semiconductor manufacturing technologies. During the development of the processor, a co-design methodology will be implemented to ensure that the processor is suitable for efficiently running many applications and that it is equipped with the appropriate software development tools. The objective of the EPI is to develop European know-how on the design and construction of processors for high-performance computing, allowing Europe technological sovereignty.
Members
EPI is a non-legal entity, a project organized by 30 inst
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https://en.wikipedia.org/wiki/Locus%20control%20region
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A locus control region (LCR) is a long-range cis-regulatory element that enhances expression of linked genes at distal chromatin sites. It functions in a copy number-dependent manner and is tissue-specific, as seen in the selective expression of β-globin genes in erythroid cells. Expression levels of genes can be modified by the LCR and gene-proximal elements, such as promoters, enhancers, and silencers. The LCR functions by recruiting chromatin-modifying, coactivator, and transcription complexes. Its sequence is conserved in many vertebrates, and conservation of specific sites may suggest importance in function. It has been compared to a super-enhancer as both perform long-range cis regulation via recruitment of the transcription complex.
History
The β-globin LCR was identified over 20 years ago in studies of transgenic mice. These studies determined that the LCR was required for normal regulation of beta-globin gene expression. Evidence of the presence of this additional regulatory element came from a group of patients that lacked a 20 kb region upstream of the β-globin cluster that was vital for expression of any of the β-globin genes. Even though all of the genes themselves and the other regulatory elements were intact, without this domain, none of the genes in the β-globin cluster were expressed.
Examples
Although the name implies that the LCR is limited to a single region, this implication only applies to the β-globin LCR (HBB-LCR). Other studies have found that a single LCR can be distributed in multiple areas around and inside the genes it controls. The β-globin LCR in mice and humans is found 6–22 kb upstream of the first globin gene (epsilon). It controls the following genes:
HBE1, hemoglobin subunit epsilon (embryonic)
HBG2, hemoglobin subunit gamma-2 (fetal)
HBG1, hemoglobin subunit gamma-1 (fetal)
HBD, hemoglobin subunit delta (adult)
HBB, hemoglobin subunit beta (adult)
There is an opsin LCR (OPSIN-LCR) controlling the expression of OPN1LW
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https://en.wikipedia.org/wiki/Selective%20area%20epitaxy
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Selective area epitaxy is the local growth of epitaxial layer through a patterned amorphous dielectric mask (typically SiO2 or Si3N4) deposited on a semiconductor substrate. Semiconductor growth conditions are selected to ensure epitaxial growth on the exposed substrate, but not on the dielectric mask. SAE can be executed in various epitaxial growth methods such as molecular beam epitaxy (MBE), metalorganic vapour phase epitaxy (MOVPE) and chemical beam epitaxy (CBE). By SAE, semiconductor nanostructures such as quantum dots and nanowires can be grown to their designed places.
Concepts
Mask
The mask used in SAE is usually amorphous dielectric such as SiO2 or SiN4 which is deposited on the semiconductor substrate. The patterns (holes) in the mask are fabricated using standard microfabrication techniques lithography and etching. Variety of lithography and etching techniques can be implemented to SAE mask fabrication. Suitable techniques depend on the pattern feature size and used materials. Electron beam lithography is widely used due to its nanometer resolution. The mask should withstand the high temperature growth conditions of semiconductors in order to limit the growth to the patterned holes in the mask.
Selectivity
Selectivity in SAE is used to express the growth on the mask. The selectivity of the growth is originated from the property that atoms doesn't favor sticking to the mask i.e. they have low sticking coefficient. Sticking coefficient can be reduced by the choice of mask material, having lower material flow and having higher growth temperature. High selectivity i.e. no growth on the mask is desired.
Growth mechanism
Epitaxial growth mechanism in SAE can be divided in to two parts: Growth before the mask level and growth after the mask level.
Growth before mask level
Before the mask level, the growth is confined to occur only in the hole in the mask. The growth starts to exceed the crystal of the substrate crystal following the pattern of the ma
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https://en.wikipedia.org/wiki/Plastochron
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As the tip of a plant shoot grows, new leaves are produced at regular time intervals if temperature is held constant. This time interval is termed the plastochron (or plastochrone). The plastochrone index and the leaf plastochron index are ways of measuring the age of a plant dependent on morphological traits rather than on chronological age. Use of these indices removes differences caused by germination, developmental differences and exponential growth.
Definitions
The spatial pattern of the arrangement of leaves is called phyllotaxy whereas the time between successive leaf initiation events is called the plastochron and the rate of emergence from the apical bud is the phyllochron.
Plastochron ratio
In 1951, F. J. Richards introduced the idea of the plastochron ratio and developed a system of equations to describe mathematically a centric representation using three parameters: plastochron ratio, divergence angle, and the angle of the cone tangential to the apex in the area being considered.
Emerging phyllodes or leaf variants experience a sudden change from a high humidity environment to a more arid one. There are other changes they encounter such as variations in light level, photoperiod and the gaseous content of the air.
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https://en.wikipedia.org/wiki/Reed%27s%20law
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Reed's law is the assertion of David P. Reed that the utility of large networks, particularly social networks, can scale exponentially with the size of the network.
The reason for this is that the number of possible sub-groups of network participants is 2N − N − 1, where N is the number of participants. This grows much more rapidly than either
the number of participants, N, or
the number of possible pair connections, N(N − 1)/2 (which follows Metcalfe's law).
so that even if the utility of groups available to be joined is very small on a per-group basis, eventually the network effect of potential group membership can dominate the overall economics of the system.
Derivation
Given a set A of N people, it has 2N possible subsets. This is not difficult to see, since we can form each possible subset by simply choosing for each element of A one of two possibilities: whether to include that element, or not.
However, this includes the (one) empty set, and N singletons, which are not properly subgroups. So 2N − N − 1 subsets remain, which is exponential, like 2N.
Quote
From David P. Reed's, "The Law of the Pack" (Harvard Business Review, February 2001, pp 23–4):
"[E]ven Metcalfe's law understates the value created by a group-forming network [GFN] as it grows. Let's say you have a GFN with n members. If you add up all the potential two-person groups, three-person groups, and so on that those members could form, the number of possible groups equals 2n. So the value of a GFN increases exponentially, in proportion to 2n. I call that Reed's Law. And its implications are profound."
Business implications
Reed's Law is often mentioned when explaining competitive dynamics of internet platforms. As the law states that a network becomes more valuable when people can easily form subgroups to collaborate, while this value increases exponentially with the number of connections, business platform that reaches a sufficient number of members can generate network effects that domin
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https://en.wikipedia.org/wiki/Physiological%20plant%20disorder
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Physiological plant disorders are caused by non-pathological conditions such as poor light, adverse weather, water-logging, phytotoxic compounds or a lack of nutrients, and affect the functioning of the plant system. Physiological disorders are distinguished from plant diseases caused by pathogens, such as a virus or fungus. While the symptoms of physiological disorders may appear disease-like, they can usually be prevented by altering environmental conditions. However, once a plant shows symptoms of a physiological disorder, it is likely that that season's growth or yield will be reduced.
Diagnosis of disorders
Diagnosis of the cause of a physiological disorder (or disease) can be difficult, but there are many web-based guides that may assist with this. Examples are: Abiotic plant disorders: Symptoms, signs and solutions; Georgia Corn Diagnostic Guide; Diagnosing Plant Problems (Kentucky); and Diagnosing Plant Problems (Virginia).
Some general tips to diagnosing plant disorders:
Examine where symptoms first appear on a plant—on new leaves, old leaves or all over?
Note the pattern of any discolouration or yellowing—is it all over, between the veins or around the edges? If only the veins are yellow, deficiency is probably not involved.
Note general patterns rather than looking at individual plants—are the symptoms distributed throughout a group of plants of the same type growing together? In the case of a deficiency all of the plants should be similarly effected, although distribution will depend on past treatments applied to the soil.
Soil analysis, such as determining pH, can help to confirm the presence of physiological disorders.
Considering recent conditions, such as heavy rains, dry spells, frosts, etc., may also help to determine the cause of plant disorders.
Weather damage
Frost and cold are major causes of crop damage to tender plants, although hardy plants can also suffer if new growth is exposed to a hard frost following a period of warm weather. Symp
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https://en.wikipedia.org/wiki/Rod%20of%20Asclepius
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In Greek mythology, the Rod of Asclepius (⚕; , , sometimes also spelled Asklepios), also known as the Staff of Aesculapius and as the asklepian, is a serpent-entwined rod wielded by the Greek god Asclepius, a deity associated with healing and medicine. In modern times, it is the predominant symbol for medicine and health care, although it is sometimes confused with the similar caduceus, which has two snakes.
Greek mythology and Greek society
The Rod of Asclepius takes its name from the Greek god Asclepius, a deity associated with healing and medicinal arts in ancient Greek religion and mythology. Asclepius' attributes, the snake and the staff, sometimes depicted separately in antiquity, are combined in this symbol.
The most famous temple of Asclepius was at Epidaurus in north-eastern Peloponnese. Another famous healing temple (or asclepeion) was located on the island of Kos, where Hippocrates, the legendary "father of medicine", may have begun his career. Other asclepieia were situated in Trikala, Gortys (Arcadia), and Pergamum in Asia.
In honor of Asclepius, a particular type of non-venomous snake was often used in healing rituals, and these snakes – the Aesculapian snakes – crawled around freely on the floor in dormitories where the sick and injured slept. These snakes were introduced at the founding of each new temple of Asclepius throughout the classical world. From about 300 BCE onwards, the cult of Asclepius grew very popular and pilgrims flocked to his healing temples (Asclepieia) to be cured of their ills. Ritual purification would be followed by offerings or sacrifices to the god (according to means), and the supplicant would then spend the night in the holiest part of the sanctuary – the abaton (or adyton). Any dreams or visions would be reported to a priest who would prescribe the appropriate therapy by a process of interpretation. Some healing temples also used sacred dogs to lick the wounds of sick petitioners.
The original Hippocratic Oath began
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https://en.wikipedia.org/wiki/Gravitational%20memory%20effect
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Gravitational memory effects, also known as gravitational-wave memory effects are predicted persistent changes in the relative position of pairs of masses in space due to the passing of a gravitational wave. Detection of gravitational memory effects has been suggested as a way of validating Einstein's Theory of General Relativity.
There are two kinds of predicted gravitational memory effect: a linear phenomenon, first proposed in 1974 by Russian scientists; and a non-linear phenomenon known as the nonlinear memory effect, which was first proposed in the 1990s.
Research on the predicted phenomena has been carried out by Ya. B. Zel'dovich and A. G. Polnarev, V. B. Braginsky and L. P. Grishchuk, and Demetrios Christodoulou.
In 2014 Andrew Strominger and Alexander Zhiboedov showed that the formula related to the memory effect is the Fourier transform in time of Weinberg's soft graviton theorem.
In 2016, a new type of memory effect induced by gravitational waves moving along opposite circular trajectories was proposed, caused by the angular momentum of the waves themselves and therefore termed gravitational spin memory. As in the previous case, this memory also turns out to be a Fourier transform in time. In this case of the graviton theorem expanded to the subleading term.
Detection
The effect should, in theory, be detectable by recording changes in the distance between pairs of free-falling objects in spacetime before and after the passage of gravitational waves. The proposed LISA detector is expected to detect the memory effect easily. In contrast, detection with the existing LIGO is complicated by two factors. First, LIGO detection targets a higher frequency range than is desirable for detection of memory effects. Secondly, LIGO is not in free-fall, and its parts will drift back to their equilibrium position following the passage of the gravitational waves. However, as thousands of events from LIGO and similar earth-based detectors are recorded and statistical
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https://en.wikipedia.org/wiki/Alt%20code
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On personal computers with numeric keypads that use Microsoft operating systems, such as Windows, many characters that do not have a dedicated key combination on the keyboard may nevertheless be entered using the Alt code (the Alt numpad input method). This is done by pressing and holding the key, then typing a number on the keyboard's numeric keypad that identifies the character and then releasing .
History and description
MS DOS
On IBM PC compatible personal computers from the 1980s, the BIOS allowed the user to hold down the key and type a decimal number on the keypad. It would place the corresponding code into the keyboard buffer so that it would look (almost) as if the code had been entered by a single keystroke. Applications reading keystrokes from the BIOS would behave according to what action they associate with that code. Some would interpret the code as a command, but often it would be interpreted as an 8-bit character from the current code page that was inserted into the text the user was typing. On the original IBM PC the code page was CP437.
Some Eastern European, Arabic and Asian computers used other hardware code pages, and MS-DOS was able to switch between them at runtime with commands like KEYB, CHCP or MODE. This causes the Alt combinations to produce different characters (as well as changing the display of any previously-entered text in the same manner). A common choice in locales using variants of the Latin alphabet was CP850, which provided more Latin character variants. (There were, however, many more code pages; for a more complete list, see code page).
PC keyboards designed for non-English use included other methods of inserting these characters, such as national keyboard layouts, the AltGr key or dead keys, but the Alt key was the only method of inserting some characters, and the only method that was the same on all machines, so it remained very popular. This input method is emulated by many pieces of software (such as later versions
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https://en.wikipedia.org/wiki/AP%20site
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In biochemistry and molecular genetics, an AP site (apurinic/apyrimidinic site), also known as an abasic site, is a location in DNA (also in RNA but much less likely) that has neither a purine nor a pyrimidine base, either spontaneously or due to DNA damage. It has been estimated that under physiological conditions 10,000 apurinic sites and 500 apyrimidinic may be generated in a cell daily.
AP sites can be formed by spontaneous depurination, but also occur as intermediates in base excision repair. In this process, a DNA glycosylase recognizes a damaged base and cleaves the N-glycosidic bond to release the base, leaving an AP site. A variety of glycosylases that recognize different types of damage exist, including oxidized or methylated bases, or uracil in DNA. The AP site can then be cleaved by an AP endonuclease, leaving 3'-hydroxyl and deoxyribose-5-phosphate termini (see DNA structure). In alternative fashion, bifunctional glycosylase-lyases can cleave the AP site, leaving a 5' phosphate adjacent to a 3' α,β-unsaturated aldehyde. Both mechanisms form a single-strand break, which is then repaired by either short-patch or long-patch base excision repair.
If left unrepaired, AP sites can lead to mutation during semiconservative replication. They can cause replication fork stalling and are bypassed by translesion synthesis. In E. coli, adenine is preferentially inserted across from AP sites, known as the "A rule". The situation is more complex in higher eukaryotes, with different nucleotides showing a preference depending on the organism and experimental conditions.
Formation
AP sites form when deoxyribose is cleaved from its nitrogenous base, breaking the glycosidic linkage between the two. This can happen spontaneously, as a result of chemical activity, radiation, or due to enzyme activity. The glycosidic linkages in DNA can be broken via acid-catalyzed hydrolysis. Purine bases can be ejected under weakly acidic conditions, while pyrimidines require stronger a
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https://en.wikipedia.org/wiki/Miniature%20Railroad%20%26%20Village
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The Miniature Railroad & Village (MRRV) is a large and detailed model train layouts diorama of western Pennsylvania from 1880 to 1930. It is a long-running display currently located in the Carnegie Science Center in Pittsburgh, Pennsylvania, the MRRV has been a Pittsburgh tradition for over 50 years.
History
The exhibit was initiated by Charles Bowdish (1896–1988) of Brookville, Pennsylvania. Bowdish was a soldier during World War I. When doctors discovered a congenital heart problem, he was honorably discharged from service and sent home, where he began to build models of structures around Brookville, his hometown. Every Christmas, in his home on Creek Street (the house has since been demolished), the buildings were assembled in a display, complete with Lionel trains running through it. On Christmas Eve 1920, Charles hosted his brother's wedding and reception, and entertained the guests by running his train display. One of the guests, Alfred Truman, asked if he could bring some friends over to see it—word quickly spread, and nearly 600 people showed up.
Because of this, Christmas Eve 1920 is considered to be the birth date of the exhibit.
Bowdish soon began setting up and exhibiting his railroad yearly at Christmas time in his house. Each year there would be a different theme, such as White Christmas or Indian Summer. The railroad spanned the entire second floor, and no admission fee was ever charged. Thousands of people saw it over the years, some coming from other countries. A combination of a flood nearly destroying his stored models, and his insurance company refusing to cover the crowds anymore, forced Charles to begin searching for a new home for his work. He originally offered it to Brookville, but the town declined.
Eventually he offered it to the Buhl Planetarium and Institute of Popular Science in Pittsburgh (renamed Buhl Science Center in the 1970s). The Buhl offered him space, and the exhibit opened there on December 1, 1954, and ran u
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https://en.wikipedia.org/wiki/NiceHash
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NiceHash is a global cryptocurrency hash power broker and cryptocurrency exchange with an open marketplace that connects sellers of hashing power (cryptominers) with buyers of hashing power using the sharing economy approach. The company provides software for cryptocurrency mining. The company was founded in 2014 by two Slovenian university students, Marko Kobal and Matjaž Škorjanc.
The company is based in The British Virgin Islands and has offices in Maribor, Slovenia. NiceHash users are primarily video gamers who have powerful graphics cards (GPUs) suited to cryptocurrency mining. The company has over 2.5 million users in 190 countries worldwide as of November 2021.
History
NiceHash was founded in 2014, a former medical student turned computer programmer, and Marko Kobal.
NiceHash's original founder Matjaž Škorjanc was allegedly one of the creators of malware called Mariposa botnet and served four years and ten months in a Slovenian prison. On June 5, 2019, US law enforcement reopened a case in the operations of the Mariposa (Butterfly Bot, BFBOT) malware gang. In 2019, The FBI moved forward with new charges and arrest warrants against four suspects, including Matjaž Škorjanc. Matjaž was detained in prison in Germany in 2019. Due to international law agreements on double jeopardy, he was released in 2020. Matjaž provided the original concept for the company, but is not involved in its operation, and the current CEO is Martin Škorjanc.
On December 6, 2017, approximately 4,700 Bitcoins (US$64 million at the time of the hack) were stolen from NiceHash allegedly by a spear phishing attack. Due to the open and transparent nature of the blockchain, the security breach received an influx of attention as the stolen sum and movement of bitcoins were visible to anyone on the internet.
On December 21, 2017, Marko Kobal resigned as the CEO of NiceHash. On that day, the company also re-opened their marketplace after the December 6th hack. NiceHash announced that they
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https://en.wikipedia.org/wiki/Signal%20magnitude%20area
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In mathematics, the signal magnitude area (abbreviated SMA or sma) is a statistical measure of the magnitude of a varying quantity.
Definition
The SMA value of a set of values (or a continuous-time waveform) is the normalized integral of the original values.
In the case of a set of n values matching a time length T, the SMA
In the continuous domain, we have for example, with a 3-axis signal with an offset correction a for each axis, the following equation:
See also
Root mean square
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https://en.wikipedia.org/wiki/The%20Miniature%20White%20House
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The Miniature White House is a detailed miniature replica of the White House created by miniaturists John and Jan Zweifel. It is kept at the Zweifels' Presidents Hall of Fame in Clermont, Florida, though portions of it are often displayed elsewhere, including at presidential libraries.
Its construction began in 1962. Built to a 1-inch-to-1-foot scale, it replicates in painstaking detail almost all the rooms in the White House, including the East Wing, West Wing, and the Oval Office.
It has been displayed in every U.S. state. In the 1970s and early 1980s, it was displayed in several foreign countries. In the Netherlands, the replica was attacked by a group of anti-American vandals, who damaged most of the model, but all was eventually repaired.
In 1994, W. W. Norton & Company published The White House in Miniature by Gail Buckland, a book about the model's history and creators that features photographs of all the miniature rooms. A VHS/DVD tour of the replica has also been made.
See also
Replicas of the White House
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https://en.wikipedia.org/wiki/Hot%20spot%20effect%20in%20subatomic%20physics
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Hot spots in subatomic physics are regions of high energy density or temperature in hadronic or nuclear matter.
Finite size effects
Hot spots are a manifestation of the finite size of the system: in subatomic physics this refers both to atomic nuclei, which consist of nucleons, as well as to nucleons themselves, which are made of quarks and gluons, Other manifestations of finite sizes of these systems are seen in scattering of electrons on nuclei and nucleons. For nuclei in particular finite size effects manifest themselves also in the isomeric shift and isotopic shift.
Statistical methods in subatomic physics
The formation of hot spots assumes the establishment of local equilibrium, which in its turn occurs if the thermal conductivity in the medium is sufficiently small.
The notions of equilibrium and heat are statistical. The use of statistical methods assumes a large number of degrees of freedom. In macroscopic physics this number usually refers to the number of atoms or molecules, while in nuclear and particle physics it refers to the energy level density.
Hot spots in nucleons
Local equilibrium is the precursor of global equilibrium and the hot spot effect can be used to determine how fast, if at all, the transition from local to global equilibrium takes place. That this transition does not always happen follows from the fact that the duration of a strong interaction reaction is quite short (of the order of 10−22–10−23 seconds) and the propagation of "heat", i.e. of the excitation, through the finite sized body of the system takes a finite time, which is determined by the thermal conductivity of the matter the system is made of.
Indications of the transition between local and global equilibrium in strong interaction particle physics started to emerge in the 1960s and early 1970s. In high-energy strong interactions equilibrium is usually not complete. In these reactions, with the increase of laboratory energy one observes that the transverse momenta of produc
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https://en.wikipedia.org/wiki/Clazuril
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Clazuril is a drug used in veterinary medicine as a coccidiostat.
See also
Diclazuril
Ponazuril
Toltrazuril
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https://en.wikipedia.org/wiki/Biosurfactant
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Biosurfactant usually refers to surfactants of microbial origin. Most of the biosurfactants produced by microbes are synthesized extracellularly and many microbes are known to produce biosurfactants in large relative quantities. Some are of commercial interest. As a secondary metabolite of microorganisms, biosurfactants can be processed by the cultivation of biosurfactant producing microorganisms in the stationary phase on many sorts of low-priced substrates like biochar, plant oils, carbohydrates, wastes, etc. High-level production of biosurfactants can be controlled by regulation of environmental factors and growth circumstances.
Classification
Biosurfactants are usually categorized by their molecular structure. Like synthetic surfactants, they are composed of a hydrophilic moiety made up of amino acids, peptides, (poly)saccharides, or sugar alcohols and a hydrophobic moiety consisting of fatty acids. Correspondingly, the significant classes of biosurfactants include glycolipids, lipopeptides and lipoproteins, and polymeric surfactants as well as particulate surfactants.
Examples
Common biosurfactants include:
Bile salts are mixtures of micelle-forming compounds that encapsulate food, enabling absorption through the small intestine.
Lecithin, which can be obtained either from soybean or from egg yolk, is a common food ingredient.
Rhamnolipids, which can be produced by some species of Pseudomonas, e.g., Pseudomonas aeruginosa.
Sophorolipids are produced by various nonpathogenic yeasts.
Emulsan produced by Acinetobacter calcoaceticus.
Microbial biosurfactants are obtained by including immiscible liquids in the growth medium.
Applications
Potential applications include herbicides and pesticides formulations, detergents, healthcare and cosmetics, pulp and paper, coal, textiles, ceramic processing and food industries, uranium ore-processing, and mechanical dewatering of peat.
Oil spill remediation
Biosurfactants enhance the emulsification of hydrocarbons, t
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https://en.wikipedia.org/wiki/Wassim%20Michael%20Haddad
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Wassim Michael Haddad (born July 14, 1961) is a Lebanese-Greek-American applied mathematician, scientist, and engineer, with research specialization in the areas of dynamical systems and control. His research has led to fundamental breakthroughs in applied mathematics, thermodynamics, stability theory, robust control, dynamical system theory, and neuroscience. Professor Haddad is a member of the faculty of the School of Aerospace Engineering at Georgia Institute of Technology, where he holds the rank of Professor and Chair of the Flight Mechanics and Control Discipline. Dr. Haddad is a member of the Academy of Nonlinear Sciences for recognition of paramount contributions to the fields of nonlinear stability theory, nonlinear dynamical systems, and nonlinear control and an IEEE Fellow for contributions to robust, nonlinear, and hybrid control systems.
Biography
Early life and education
Haddad was born in Athens, Greece, to a Greek mother and Lebanese father. He attended a private British secondary school for his early education and the American Community Schools in Athens and Beirut, respectively, for his high school education. After completing his high school, where he was taught Greek, French, philosophy, and basic science and mathematics, in 1979 he entered the Mechanical and Aerospace Engineering Department of the Florida Institute of Technology in Melbourne, Florida. Haddad received the B.S., M.S., and Ph.D. degrees in mechanical engineering from Florida Tech in 1983, 1984, and 1987, respectively, with specialization in dynamical systems and control. His doctoral research concentrated on fixed-architecture robust control design with applications to large flexible space structures and with Dennis S. Bernstein serving as his doctoral advisor.
Academic career
From 1987 to 1994 Haddad served as a consultant for the Structural Controls Group of the Government Aerospace Systems Division, Harris Corporation, Melbourne, Florida. In 1988 he joined the faculty of th
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https://en.wikipedia.org/wiki/Semisimple%20operator
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In mathematics, a linear operator T : V → V on a vector space V is semisimple if every T-invariant subspace has a complementary T-invariant subspace. If T is a semisimple linear operator on V, then V is a semisimple representation of T. Equivalently, a linear operator is semisimple if its minimal polynomial is a product of distinct irreducible polynomials.
A linear operator on a finite dimensional vector space over an algebraically closed field is semisimple if and only if it is diagonalizable.
Over a perfect field, the Jordan–Chevalley decomposition expresses an endomorphism as a sum of a semisimple endomorphism s and a nilpotent endomorphism n such that both s and n are polynomials in x.
See also
Jordan–Chevalley decomposition
Notes
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https://en.wikipedia.org/wiki/Lightning
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Lightning is a natural phenomenon formed by electrostatic discharges through the atmosphere between two electrically charged regions, either both in the atmosphere or with one in the atmosphere and on the ground, temporarily neutralizing these in a near-instantaneous release of an average of one gigajoule of energy. This discharge may produce a wide range of electromagnetic radiation, from heat created by the rapid movement of electrons, to brilliant flashes of visible light in the form of black-body radiation. Lightning causes thunder, a sound from the shock wave which develops as gases in the vicinity of the discharge experience a sudden increase in pressure. Lightning occurs commonly during thunderstorms as well as other types of energetic weather systems, but volcanic lightning can also occur during volcanic eruptions. Lightning is an atmospheric electrical phenomenon and contributes to the global atmospheric electrical circuit.
The three main kinds of lightning are distinguished by where they occur: either inside a single thundercloud (intra-cloud), between two clouds (cloud-to-cloud), or between a cloud and the ground (cloud-to-ground), in which case it is referred to as a lightning strike. Many other observational variants are recognized, including "heat lightning", which can be seen from a great distance but not heard; dry lightning, which can cause forest fires; and ball lightning, which is rarely observed scientifically.
Humans have deified lightning for millennia. Idiomatic expressions derived from lightning, such as the English expression "bolt from the blue", are common across languages. At all times people have been fascinated by the sight and difference of lightning. The fear of lightning is called astraphobia.
The first known photograph of lightning is from 1847, by Thomas Martin Easterly. The first surviving photograph is from 1882, by William Nicholson Jennings, a photographer who spent half his life capturing pictures of lightning and proving i
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https://en.wikipedia.org/wiki/Matrix%20variate%20Dirichlet%20distribution
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In statistics, the matrix variate Dirichlet distribution is a generalization of the matrix variate beta distribution and of the Dirichlet distribution.
Suppose are positive definite matrices with also positive-definite, where is the identity matrix. Then we say that the have a matrix variate Dirichlet distribution, , if their joint probability density function is
where and is the multivariate beta function.
If we write then the PDF takes the simpler form
on the understanding that .
Theorems
generalization of chi square-Dirichlet result
Suppose are independently distributed Wishart positive definite matrices. Then, defining (where is the sum of the matrices and is any reasonable factorization of ), we have
Marginal distribution
If , and if , then:
Conditional distribution
Also, with the same notation as above, the density of is given by
where we write .
partitioned distribution
Suppose and suppose that is a partition of (that is, and if ). Then, writing and (with ), we have:
partitions
Suppose . Define
where is and is . Writing the Schur complement we have
and
See also
Inverse Dirichlet distribution
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https://en.wikipedia.org/wiki/Spread%20of%20a%20matrix
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In mathematics, and more specifically matrix theory, the spread of a matrix is the largest distance in the complex plane between any two eigenvalues of the matrix.
Definition
Let be a square matrix with eigenvalues . That is, these values are the complex numbers such that there exists a vector on which acts by scalar multiplication:
Then the spread of is the non-negative number
Examples
For the zero matrix and the identity matrix, the spread is zero. The zero matrix has only zero as its eigenvalues, and the identity matrix has only one as its eigenvalues. In both cases, all eigenvalues are equal, so no two eigenvalues can be at nonzero distance from each other.
For a projection, the only eigenvalues are zero and one. A projection matrix therefore has a spread that is either (if all eigenvalues are equal) or (if there are two different eigenvalues).
All eigenvalues of a unitary matrix lie on the unit circle. Therefore, in this case, the spread is at most equal to the diameter of the circle, the number 2.
The spread of a matrix depends only on the spectrum of the matrix (its multiset of eigenvalues). If a second matrix of the same size is invertible, then has the same spectrum as . Therefore, it also has the same spread as .
See also
Field of values
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https://en.wikipedia.org/wiki/Kuehneromyces%20mutabilis
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Kuehneromyces mutabilis (synonym: Pholiota mutabilis), commonly known as the sheathed woodtuft, is an edible mushroom that grows in clumps on tree stumps or other dead wood. A few other species have been described in the genus Kuehneromyces, but K. mutabilis is by far the most common and best known.
Description
The clustered shiny convex caps are 6–8 cm in diameter. They are very hygrophanous; in a damp state they are shiny and greasy with a deep orange-brown colour towards the rim; often there is a disc of lighter (less sodden) flesh in the middle. In a dry state they are cinnamon-coloured.
The gills are initially light and later cinnamon brown, and are sometimes somewhat decurrent (running down the stem).
The stipe is 8–10 cm long by about 0.5–1 cm in diameter with a ring which separates the bare, smooth light cinnamon upper part from the darker brown shaggily scaly lower part. This type of stem is sometimes described as "booted".
This species always grows on wood, generally on stumps of broad-leaved trees (especially beech, birch and alder), and rarely on conifers.
It is found from April to late October, and also in the remaining winter months where conditions are mild. It is often seen at times when there are few other fungi in evidence.
Range
Kuehneromyces mutabilis is found in Australia, Asia (in the Caucuses, Siberia, and Japan), North America, and Europe. In Europe, it can be found from Southern Europe to Iceland and Scandinavia.
Warning about consumption
K. mutabilis cannot be recommended for consumption as it could be confused with the deadly poisonous Galerina marginata, even by people who are quite knowledgeable. Although a typical K. mutabilis is easily distinguished from a typical G. marginata by the "booted" stipe which is shaggy below the ring (see photos), this character is not reliable and G. marginata can also have scales. The main differences are:
While they are both hygrophanous, K. mutabilis dries from the centre outwards (so havi
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https://en.wikipedia.org/wiki/BAH%20domain
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In molecular biology, the BAH domain (bromo-adjacent homology) domain is found in proteins such as eukaryotic DNA (cytosine-5) methyltransferases, the origin recognition complex 1 (Orc1) proteins, Bromo adjacent homology domain containing 1 (BAHD1), as well as several proteins involved in transcriptional regulation. The BAH domain appears to act as a protein-protein interaction module specialised in gene silencing, as suggested for example by its interaction within yeast Orc1p with the silent information regulator Sir1p. The BAH domain might therefore play an important role by linking DNA methylation, replication and transcriptional regulation.
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https://en.wikipedia.org/wiki/Scenario%20%28computing%29
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In computing, a scenario (, ; loaned (), ) is a narrative of foreseeable interactions of user roles (known in the Unified Modeling Language as 'actors') and the technical system, which usually includes computer hardware and software.
A scenario has a goal, which is usually functional. A scenario describes one way that a system is used, or is envisaged to be used, in the context of an activity in a defined time-frame. The time-frame for a scenario could be (for example) a single transaction; a business operation; a day or other period; or the whole operational life of a system. Similarly the scope of a scenario could be (for example) a single system or a piece of equipment; an equipped team or a department; or an entire organization.
Scenarios are frequently used as part of the system development process. They are typically produced by usability or marketing specialists, often working in concert with end users and developers. Scenarios are written in plain language, with minimal technical details, so that stakeholders (designers, usability specialists, programmers, engineers, managers, marketing specialists, etc.) can have a common ground to focus their discussions.
Increasingly, scenarios are used directly to define the wanted behaviour of software: replacing or supplementing traditional functional requirements. Scenarios are often defined in use cases, which document alternative and overlapping ways of reaching a goal.
Types of scenario in system development
Many types of scenario are in use in system development. Alexander and Maiden list the following types:
Story: "a narrated description of a causally connected sequence of events, or of actions taken". Brief User stories are written in the Agile style of software development.
Situation, Alternative World: "a projected future situation or snapshot". This meaning is common in planning, but less usual in software development.
Simulation: use of models to explore and animate 'Stories' or 'Situations', to
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https://en.wikipedia.org/wiki/IEEE%20Cloud%20Computing
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IEEE Cloud Computing is a global initiative launched by IEEE to promote cloud computing, big data and related technologies, and to provide expertise and resources to individuals and enterprises involved in cloud computing.
History
In 2010, the Institute of Electrical and Electronics Engineers (IEEE) sponsored two cloud computing–specific conferences: IEEE CLOUD and IEEE CloudCom. With the success of the two conferences, IEEE Senior Member and IEEE Computer Society past president Steve Diamond, began urging the organization to take an active role in the development of cloud computing standards.
In April 2011, with the support of the IEEE Future Directions Committee and funding from the IEEE New Initiatives Committee, IEEE Cloud Computing was launched. The initiative was designed to follow a multi-year plan and includes a focus across multiple tracks: conferences, education, publications, standards, Intercloud Testbed, web portal, marketing, and public relations.
As part of the initiative's launch, two new cloud computing standards development projects were approved: IEEE P2301, Draft Guide for Cloud Portability and Interoperability Profile, and IEEE P2302, Draft Standard for Intercloud Interoperability and Federation (SIIF). With a growing need for greater cloud computing interoperability and federation, IEEE Cloud Computing focused its development activities and resources behind IEEE P2302 standard.
Current work
IEEE Cloud Computing continues to pursue efforts to provide cloud computing standards, advancement of cloud computing technologies, and to educate users on the benefits of cloud computing. As part of this ongoing effort, it offers a variety of activities, products, and services, including the IEEE Cloud Computing portal, conferences and events, continuing education courses, publications, standards, and the IEEE Intercloud Testbed platform for testing cloud computing interoperability.
IEEE Cloud Computing web portal
The IEEE Cloud Computing portal ser
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https://en.wikipedia.org/wiki/Erd%C5%91s%E2%80%93Szekeres%20theorem
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In mathematics, the Erdős–Szekeres theorem asserts that, given r, s, any sequence of distinct real numbers with length at least (r − 1)(s − 1) + 1 contains a monotonically increasing subsequence of length r or a monotonically decreasing subsequence of length s. The proof appeared in the same 1935 paper that mentions the Happy Ending problem.
It is a finitary result that makes precise one of the corollaries of Ramsey's theorem. While Ramsey's theorem makes it easy to prove that every infinite sequence of distinct real numbers contains a monotonically increasing infinite subsequence or a monotonically decreasing infinite subsequence, the result proved by Paul Erdős and George Szekeres goes further.
Example
For r = 3 and s = 2, the formula tells us that any permutation of three numbers has an increasing subsequence of length three or a decreasing subsequence of length two. Among the six permutations of the numbers 1,2,3:
1,2,3 has an increasing subsequence consisting of all three numbers
1,3,2 has a decreasing subsequence 3,2
2,1,3 has a decreasing subsequence 2,1
2,3,1 has two decreasing subsequences, 2,1 and 3,1
3,1,2 has two decreasing subsequences, 3,1 and 3,2
3,2,1 has three decreasing length-2 subsequences, 3,2, 3,1, and 2,1.
Alternative interpretations
Geometric interpretation
One can interpret the positions of the numbers in a sequence as x-coordinates of points in the Euclidean plane, and the numbers themselves as y-coordinates; conversely, for any point set in the plane, the y-coordinates of the points, ordered by their x-coordinates, forms a sequence of numbers (unless two of the points have equal x-coordinates). With this translation between sequences and point sets, the Erdős–Szekeres theorem can be interpreted as stating that in any set of at least rs − r − s + 2 points we can find a polygonal path of either r − 1 positive-slope edges or s − 1 negative-slope edges. In particular (taking r = s), in any set of at least n points we can find a
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https://en.wikipedia.org/wiki/BURP%20domain
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In molecular biology, the BURP domain is a ~230-amino acid protein domain, which has been named for the four members of the group initially identified, BNM2, USP, RD22, and PG1beta. It is found in the C-terminal part of a number of plant cell wall proteins, which are defined not only by the BURP domain, but also by the overall similarity in their modular construction. The BURP domain proteins consists of either three or four modules: (i) an N-terminal hydrophobic domain - a presumptive transit peptide, joined to (ii) a short conserved segment or other short segment, (iii) an optional segment consisting of repeated units which is unique to each member, and (iv) the C-terminal BURP domain. Although the BURP domain proteins share primary structural features, their expression patterns and the conditions under which they are expressed differ. The presence of the conserved BURP domain in diverse plant proteins suggests an important role for this domain. It is possible that the BURP domain represents a general motif for localization of proteins within the cell wall matrix. The other structural domains associated with the BURP domain may specify other target sites for intermolecular interactions.
Some proteins known to contain a BURP domain are listed below:
Brassica protein BNM2, which is expressed during the induction of microspore embryogenesis.
Field bean USPs, abundant non-storage seed proteins with unknown function.
Soybean USP-like proteins ADR6 (or SALI5-4A), an auxin-repressible, aluminium-inducible protein and SALI3-2, a protein that is up-regulated by aluminium.
Soybean seed coat BURP-domain protein 1 (SCB1). It might play a role in the differentiation of the seed coat parenchyma cells.
Arabidopsis RD22 drought induced protein.
Maize ZRP2, a protein of unknown function in cortex parenchyma.
Tomato PG1beta, the beta-subunit of polygalacturonase isozyme 1 (PG1), which is expressed in ripening fruits.
Cereal RAFTIN. It is essential specifically for the maturation
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https://en.wikipedia.org/wiki/Comet%20%28programming%29
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Comet is a web application model in which a long-held HTTPS request allows a web server to push data to a browser, without the browser explicitly requesting it. Comet is an umbrella term, encompassing multiple techniques for achieving this interaction. All these methods rely on features included by default in browsers, such as JavaScript, rather than on non-default plugins. The Comet approach differs from the original model of the web, in which a browser requests a complete web page at a time.
The use of Comet techniques in web development predates the use of the word Comet as a neologism for the collective techniques. Comet is known by several other names, including
Ajax Push,
Reverse Ajax, Two-way-web, HTTP Streaming, and
HTTP server push
among others. The term Comet is not an acronym, but was coined by Alex Russell in his 2006 blog post.
In recent years, the standardisation and widespread support of WebSocket and Server-sent events has rendered the Comet model obsolete.
History
Early Java applets
The ability to embed Java applets into browsers (starting with Netscape Navigator 2.0 in March 1996) made two-way sustained communications possible, using a raw TCP socket to communicate between the browser and the server. This socket can remain open as long as the browser is at the document hosting the applet. Event notifications can be sent in any format text or binary and decoded by the applet.
The first browser-to-browser communication framework
The very first application using browser-to-browser communications was Tango Interactive, implemented in 1996–98 at the Northeast Parallel Architectures Center (NPAC) at Syracuse University using DARPA funding. TANGO architecture has been patented by Syracuse University. TANGO framework has been extensively used as a distance education tool. The framework has been commercialized by CollabWorx and used in a dozen or so Command&Control and Training applications in the United States Department of Defense.
First Comet appli
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https://en.wikipedia.org/wiki/Yoke%20and%20arrows
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The yoke and arrows () or the yoke and the bundle of arrows () is a symbolic badge dating back to the dynastic union of Spain's Catholic monarchs Ferdinand II of Aragon and Isabella I of Castile. Subsequent Catholic monarchs continued to use it on their shields to represent a united Spain and symbolize "the heroic virtues of the race".
It was also an allusion to the names of the founding monarchs: Y stood for yugo and for Ysabel (in contemporary spelling) and F stood for flechas and for Ferdinand. The yoke referred to the legend of the Gordian knot, as did Isabel and Ferdinand's motto Tanto monta; the bundle of arrows alluded to the ancient proverb that arrows can be easily broken one by one, but are unbreakable if tied together.
The Spanish Empire
Many possessions of the Spanish Empire incorporated the yoke and arrows into their coats of arms. Although these countries and territories are no longer part of Spain, some of them retain this symbol in their heraldry.
In recent history
The yoke and arrows became a political symbol of the Fascist Falange when it was founded in 1934, and during the Spanish Civil War it was used as one of the major emblems of the Nationalist faction. After they won the war, Falange became the sole legal party in Spain and their yoke and arrows also was a main symbol of the Francoist regime. It was eventually removed during the Spanish transition to democracy, together with the also appropriated Eagle of Saint John.
From then on, it is no longer representative of Spain or its monarchy and has been considered a symbol of the Fascist far-right, though it continued to be present in the personal coat of arms of King Juan Carlos I. Upon his accession to the Spanish throne, King Felipe VI discontinued their use as part of his personal coat of arms.
See also
Symbols of Francoism
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https://en.wikipedia.org/wiki/John%20Herivel
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John William Jamieson Herivel (29 August 1918 – 18 January 2011) was a British science historian and World War II codebreaker at Bletchley Park.
As a codebreaker concerned with Cryptanalysis of the Enigma, Herivel is remembered chiefly for the discovery of what was soon dubbed the Herivel tip or Herivelismus. Herivelismus consisted of the idea, the Herivel tip and the method of establishing whether it applied using the Herivel square. It was based on Herivel's insight into the habits of German operators of the Enigma cipher machine that allowed Bletchley Park to easily deduce part of the daily key. For a brief but critical period after May 1940, the Herivel tip in conjunction with "cillies" (another class of operator error) was the main technique used to solve Enigma.
After the war, Herivel became an academic, studying the history and philosophy of science at Queen's University Belfast, particularly Isaac Newton, Joseph Fourier, Christiaan Huygens. In 1956, he took a brief leave of absence from Queen's to work as a scholar at the Dublin Institute for Advanced Studies. In retirement, he wrote an autobiographical account of his work at Bletchley Park entitled Herivelismus and the German Military Enigma.
Recruitment to Bletchley Park
John Herivel was born in Belfast, and attended Methodist College Belfast from 1924 to 1936. In 1937 he was awarded a Kitchener Scholarship to study mathematics at Sidney Sussex College, Cambridge, where his supervisor was Gordon Welchman. Welchman recruited Herivel to the Government Code and Cypher School (GC&CS) at Bletchley Park. Welchman worked with Alan Turing in the newly formed Hut 6 section created to solve Army and Air Force Enigma. Herivel, then aged 21, arrived at Bletchley on 29 January 1940, and was briefed on Enigma by Alan Turing and Tony Kendrick.
Enigma
At the time that Herivel started work at Bletchley Park, Hut 6 was having only limited success with Enigma-enciphered messages, mostly from the Luftwaffe Enigma network
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https://en.wikipedia.org/wiki/250%20%28number%29
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250 (two hundred [and] fifty) is the natural number following 249 and preceding 251.
250 is also the sum of squares of the divisors of the number 14.
250 has the same digits and prime factors.
Integers between 251 and 259
251
252
253
254
255
256
257
258
259
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https://en.wikipedia.org/wiki/Historical%20hydroculture
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This is a history of notable hydroculture phenomena. Ancient hydroculture proposed sites and modern revolutionary works are mentioned. Included in this history are all forms of aquatic and semi-aquatic based horticulture that focus on flora: aquatic gardening, semi-aquatic crop farming, hydroponics, aquaponics, passive hydroponics, and modern aeroponics.
Hanging Gardens of Babylon
One of the wonders of the ancient world was irrigated by the Euphrates River. It is uncertain if Sammu-ramat or Nebuchadnezzar II ordered them to be built between 8th and 7th century BC Babylonia. The gardens were built partially on top of ziggurats, and plants were irrigated on channels. No direct evidence of the Hanging Gardens of Babylon exists. However, there is archeological evidence, uncovered by Robert Koldewey, that ancient structures exist to support the technology used for these gardens. Ancient Greeks Diodorus Siculus and Strabo have noted the Hanging Babylonian Gardens.
Precolonial America
A chinampa is a floating garden armada in a lake from the Xochimilco region, once Chinampan, of Mexico. This floating garden, still in use, can have an area of up to 10 meters by 200 meters.
The agricultural output of the chinampa allowed the postclassic Aztec civilization to flourish.
Historical Orient
Historically, fish have been raised within flooded rice fields in Indochina and China.
Living root bridges
There are 500-year-old bridges made by living roots in India, sculpted by the War-Khasis. These trees span rivers, and may be limited in connectivity to hydroculture.
Modern
Hydroculture found in nature
Ōhi'a Lehua, Metrosideros polymorpha, is a Hawaiian plant with roots that can grow suspended in extinct lava tubes. The roots of this plant are able to penetrate deep into the volcanic rock, to reach these hollow tubes, where they can collect moisture.
See also
Botanical garden history
History of agriculture
History of gardening
Horticulture
Incan agriculture
Nanfang Caom
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https://en.wikipedia.org/wiki/Spherical%20neutron%20polarimetry
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Spherical neutron polarimetry (SNP) is a form of neutron polarimetry that measures the polarization of neutrons both before and after scattering. It uses controlled magnetic fields to manipulate the spin of the neutrons, which are then separated by the Meissner effect, allowing polarization to be measured.
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https://en.wikipedia.org/wiki/Ramathallus
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Ramathallus is a genus of sessile lobate alga that represents a probable stem-Rhodophyte from the Proterozoic. The holotype of Ramathallus lobatus shows a cell structure with finger-like protrusions and a coating of non-cellular apatic. The cells have a dark granular material inside of them. The organism grew by apical growth and possessed pseudoparenchymatous thallus which in turn infer a possible affinity with the Florideophyceae. Many lobate protrusions radiated from the organisms centre composed out of pseudoparenchymatous tissue interpreted as "Cell fountains" made up of variably-sized cells. Ramathallus shares a close morphological similarity with the Ediacaran genera made up of pseudoparenchymatous, lobate fossils from the Doushantuo phosphorites of China Thallophyca, Thallophycoides, Paramecia and Gremiphyca.
See also
Proterozoic
Red algae
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https://en.wikipedia.org/wiki/GermaNet
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GermaNet is a semantic network for the German language. It relates nouns, verbs, and adjectives semantically by grouping lexical units that express the same concept into synsets and by defining semantic relations between these synsets. GermaNet is free for academic use, after signing a license. GermaNet has much in common with the English WordNet and can be viewed as an on-line thesaurus or a light-weight ontology. GermaNet has been developed and maintained at the University of Tübingen since 1997 within the research group for General and Computational Linguistics. It has been integrated into the EuroWordNet, a multilingual lexical-semantic database.
Database
Contents
GermaNet partitions the lexical space into a set of concepts that are interlinked by semantic relations. A semantic concept is modeled by a synset. A synset is a set of words (called lexical units) where all the words are taken to have the same or almost the same meaning. Thus, a synset is a set of synonyms grouped under one definition, or "gloss".
In addition to the gloss, synsets are labeled with their syntactic function and accompanied by example sentences for each distinct meaning in the synset. Just as in WordNet, for each word category the semantic space is divided into a number of semantic fields closely related to major nodes in the semantic network: Ort, or "location", Körper, or "body", etc.
As of version 15.0 (release May 2020), GermaNet contains:
Synsets: 144113
Lexical Units: 185000
Literals: 169521
Conceptual Relations: 157921
Lexical Relations (synonymy excluded): 12203
Split Compounds: 98905
Interlingual Index (ILI) Records: 28564
Wiktionary Sense Descriptions: 29548
Format
All GermaNet data is stored in a PostgreSQL relational database. The database schema follows the internal structure of GermaNet: there are tables to store synsets, lexical units, conceptual and lexical relations, etc. GermaNet data is distributed both in this database format and as XML files. In the
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https://en.wikipedia.org/wiki/Spinothalamic%20tract
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The spinothalamic tract is a part of the anterolateral system or the ventrolateral system, a sensory pathway to the thalamus. From the ventral posterolateral nucleus in the thalamus, sensory information is relayed upward to the somatosensory cortex of the postcentral gyrus.
The spinothalamic tract consists of two adjacent pathways: anterior and lateral. The anterior spinothalamic tract carries information about crude touch. The lateral spinothalamic tract conveys pain and temperature.
In the spinal cord, the spinothalamic tract has somatotopic organization. This is the segmental organization of its cervical, thoracic, lumbar, and sacral components, which is arranged from most medial to most lateral respectively.
The pathway crosses over (decussates) at the level of the spinal cord, rather than in the brainstem like the dorsal column-medial lemniscus pathway and lateral corticospinal tract. It is one of the three tracts which make up the anterolateral system.
Structure
There are two main parts of the spinothalamic tract:
The lateral spinothalamic tract transmits pain and temperature.
The anterior spinothalamic tract (or ventral spinothalamic tract) transmits crude touch and firm pressure.
The spinothalamic tract, like the dorsal column-medial lemniscus pathway, uses three neurons to convey sensory information from the periphery to conscious level at the cerebral cortex.
Pseudounipolar neurons in the dorsal root ganglion have axons that lead from the skin into the dorsal spinal cord where they ascend or descend one or two vertebral levels via Lissauer's tract and then synapse with secondary neurons in either the substantia gelatinosa of Rolando or the nucleus proprius. These secondary neurons are called tract cells.
The axons of the tract cells cross over (decussate) to the other side of the spinal cord via the anterior white commissure, and to the anterolateral corner of the spinal cord (hence the spinothalamic tract being part of the anterolateral syste
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https://en.wikipedia.org/wiki/SolveSpace
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SolveSpace is a free and open-source 2D/3D constraint-based parametric computer-aided design (CAD) software that supports basic 2D and 3D constructive solid geometry modeling.
It is a constraint-based parametric modeler with simple mechanical simulation capabilities. Version 2.1 and onward runs on Windows, Linux and macOS. The Linux version is shipped as a snap and native packages. It supports STEP and DFX for import and export. By default, SolveSpace utilizes its own CAD file format called for model storage. It is possible to export models as a whole or in part to various formats such as PDF, SVG, or Encapsulated PostScript (EPS).
It was initially created by Jonathan Westhues and as of 2022 is maintained by a community of volunteers.
History
Development of SolveSpace started in 2008 as commercial proprietary software for Microsoft Windows. A previous software package called SketchFlat, also developed by Westhues, was replaced by SolveSpace.
In 2012 version 1.9 released as unrestricted freeware proprietary software. In 2013 version 2.0 released as free and open-source software. In 2016 version 2.1 brings support for Linux and MacOS.
According to an interview given in 2020 by a major maintainer SolveSpace aims to be backwards compatibile as much as possible. The codebase at the time was about 30,000 lines of code and it took Whitequark almost 2 years to familiarize herself with it. On September 22, 2020, Whitequark stepped down as a maintainer.
Overview
SolveSpace is free and open source software distributed under the GPL-3.0-or-later license.
Features
SolveSpace is shipped with the following basic features:
2D Sketch Modeling
SolveSpace supports parametric 2D drawing of lines, circles, arcs, Cubic bézier curves etc; datum points and lines are also supported for general, reference based modeling.
3D Solid Modeling
Drawing, extrusion, rotation and revolution along a helix are supported in both modes. In 3D it is possible to use basic Boolean operations (uni
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https://en.wikipedia.org/wiki/Joshua%20Shaevitz
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Joshua Shaevitz (born 1977) is an American biophysicist and Professor of Physics at the Lewis-Sigler Institute at Princeton University in Princeton, NJ. He is known for his work in single-molecule biophysics, bacterial growth and motility, and animal behavior.
Education and early career
Shaevitz completed his Bachelor's degree in Physics at Columbia University in New York in 1999 where he was an I. I. Rabi Scholar. He received his PhD in 2004 from Stanford University where he studied the molecular motors kinesin and RNA polymerase using optical tweezers in the group of Steven Block. Shaevitz then moved to the University of California, Berkeley as a Miller Fellow. There, he focused on the motility of bacteria, including the actin-propelled Rickettsia rickettsii, Myxococcus xanthus, and the wall-less Spiroplasma. Since 2007, Shaevitz has been on the faculty of Princeton University with appointments in the Department of Physics and the Lewis-Sigler Institute for Integrative Genomics where he holds the rank of Professor.
Research
Shaevitz's work focuses on precision measurements in a variety of biological systems, focusing on topics related to cell shape in bacteria, active matter and pattern formation in groups of moving cells, and the quantification of animal behavior.
His group pioneered the use of 3D live-cell imaging to study the shape of bacteria during growth. In a series of papers, Shaevitz and colleagues unraveled how a cell-wall insertion mechanism with helical coordination can produce cells with the correct shape in both rod and helical cells. His group also studies bacterial cell mechanics, including bending rigidity, turgor pressure and cell wall stiffness, and pressure regulation.
Shaevitz also has worked on the mechanisms of gliding motility and collective behavior in the social bacterium Myxococcus xanthus. This work includes measurement of the mechanochemistry of individual gliding motors inside live bacteria and the connection between active matt
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https://en.wikipedia.org/wiki/Normalization%20%28statistics%29
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In statistics and applications of statistics, normalization can have a range of meanings. In the simplest cases, normalization of ratings means adjusting values measured on different scales to a notionally common scale, often prior to averaging. In more complicated cases, normalization may refer to more sophisticated adjustments where the intention is to bring the entire probability distributions of adjusted values into alignment. In the case of normalization of scores in educational assessment, there may be an intention to align distributions to a normal distribution. A different approach to normalization of probability distributions is quantile normalization, where the quantiles of the different measures are brought into alignment.
In another usage in statistics, normalization refers to the creation of shifted and scaled versions of statistics, where the intention is that these normalized values allow the comparison of corresponding normalized values for different datasets in a way that eliminates the effects of certain gross influences, as in an anomaly time series. Some types of normalization involve only a rescaling, to arrive at values relative to some size variable. In terms of levels of measurement, such ratios only make sense for ratio measurements (where ratios of measurements are meaningful), not interval measurements (where only distances are meaningful, but not ratios).
In theoretical statistics, parametric normalization can often lead to pivotal quantities – functions whose sampling distribution does not depend on the parameters – and to ancillary statistics – pivotal quantities that can be computed from observations, without knowing parameters.
Examples
There are different types of normalizations in statistics – nondimensional ratios of errors, residuals, means and standard deviations, which are hence scale invariant – some of which may be summarized as follows. Note that in terms of levels of measurement, these ratios only make sense for ratio me
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https://en.wikipedia.org/wiki/Universal%20Darwinism
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Universal Darwinism, also known as generalized Darwinism, universal selection theory, or Darwinian metaphysics, is a variety of approaches that extend the theory of Darwinism beyond its original domain of biological evolution on Earth. Universal Darwinism aims to formulate a generalized version of the mechanisms of variation, selection and heredity proposed by Charles Darwin, so that they can apply to explain evolution in a wide variety of other domains, including psychology, linguistics, economics, culture, medicine, computer science, and physics.
Basic mechanisms
At the most fundamental level, Charles Darwin's theory of evolution states that organisms evolve and adapt to their environment by an iterative process. This process can be conceived as an evolutionary algorithm that searches the space of possible forms (the fitness landscape) for the ones that are best adapted. The process has three components:
variation of a given form or template. This is usually (but not necessarily) considered to be blind or random, and happens typically by mutation or recombination.
selection of the fittest variants, i.e. those that are best suited to survive and reproduce in their given environment. The unfit variants are eliminated.
heredity or retention, meaning that the features of the fit variants are retained and passed on, e.g. in offspring.
After those fit variants are retained, they can again undergo variation, either directly or in their offspring, starting a new round of the iteration. The overall mechanism is similar to the problem-solving procedures of trial-and-error or generate-and-test: evolution can be seen as searching for the best solution for the problem of how to survive and reproduce by generating new trials, testing how well they perform, eliminating the failures, and retaining the successes.
The generalization made in "universal" Darwinism is to replace "organism" by any recognizable pattern, phenomenon, or system. The first requirement is that the p
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https://en.wikipedia.org/wiki/Donaldson%E2%80%93Thomas%20theory
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In mathematics, specifically algebraic geometry, Donaldson–Thomas theory is the theory of Donaldson–Thomas invariants. Given a compact moduli space of sheaves on a Calabi–Yau threefold, its Donaldson–Thomas invariant is the virtual number of its points, i.e., the integral of the cohomology class 1 against the virtual fundamental class. The Donaldson–Thomas invariant is a holomorphic analogue of the Casson invariant. The invariants were introduced by . Donaldson–Thomas invariants have close connections to Gromov–Witten invariants of algebraic three-folds and the theory of stable pairs due to Rahul Pandharipande and Thomas.
Donaldson–Thomas theory is physically motivated by certain BPS states that occur in string and gauge theorypg 5. This is due to the fact the invariants depend on a stability condition on the derived category of the moduli spaces being studied. Essentially, these stability conditions correspond to points in the Kahler moduli space of a Calabi-Yau manifold, as considered in mirror symmetry, and the resulting subcategory is the category of BPS states for the corresponding SCFT.
Definition and examples
The basic idea of Gromov–Witten invariants is to probe the geometry of a space by studying pseudoholomorphic maps from Riemann surfaces to a smooth target. The moduli stack of all such maps admits a virtual fundamental class, and intersection theory on this stack yields numerical invariants that can often contain enumerative information. In similar spirit, the approach of Donaldson–Thomas theory is to study curves in an algebraic three-fold by their equations. More accurately, by studying ideal sheaves on a space. This moduli space also admits a virtual fundamental class and yields certain numerical invariants that are enumerative.
Whereas in Gromov–Witten theory, maps are allowed to be multiple covers and collapsed components of the domain curve, Donaldson–Thomas theory allows for nilpotent information contained in the sheaves, however, these
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https://en.wikipedia.org/wiki/Tom%20Walshaw
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Tom D. Walshaw (1912–1998) was an engineer, author and contributor to the British magazines Model Engineer and Engineering in Miniature. Many of his magazine contributions and books were authored under the pseudonym Tubal Cain. The pseudonym relates to the Tubal-cain, the biblical metal worker. As Tubal Cain he made over 424 contributions to Model Engineer, beginning in 1971. These were mainly divided between workshop equipment articles and model stationary engine constructional articles. He graduated in mechanical engineering at Loughborough University in 1934. and eventually, after a career in mechanical design, went back to that university in 1943, becoming, after some years, senior lecturer in mechanical engineering. He went on in 1948 to teach at University of Liverpool. In 1952 he was appointed Head of Department of Mechanical, Civil and Electrical Engineering at Darlington College of Technology. His final academic post was Head of Mechanical, Production and Civil Engineering at Lancashire Polytechnic. He gained the first of his many model engineering exhibition awards in 1949. At one point he was editor of the Transactions of the Newcomen Society. Walshaw died on 2 May 1998.
Model stationary steam engine designs
Among his most notable contributions to Model Engineer were constructional series detailing models of steam engines dating from the Industrial Revolution:
A Vertical Columnar Engine. A model of the "Williamson" engine (serialised in 1976)
Mary, a four-column beam engine (serialised in 1977)
Lady Stephanie, six-column tank-bed beam engine
Georgina, a 19th-century overcrank engine (serialised in 1980–81)
Boreas, a Crowther-type blast furnace blowing engine (serialised in 1983–84)
Princess Royal & Goliath: variants on mid-19th century mill engines (serialised in 1984–86)
Trevithick's Dredger Engine (serialised in 1987–88)
Books published
Walshaw published the following under his own name:
Diesel engine design. London: George Newnes, 1949 (448 p
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https://en.wikipedia.org/wiki/Fermionic%20field
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In quantum field theory, a fermionic field is a quantum field whose quanta are fermions; that is, they obey Fermi–Dirac statistics. Fermionic fields obey canonical anticommutation relations rather than the canonical commutation relations of bosonic fields.
The most prominent example of a fermionic field is the Dirac field, which describes fermions with spin-1/2: electrons, protons, quarks, etc. The Dirac field can be described as either a 4-component spinor or as a pair of 2-component Weyl spinors. Spin-1/2 Majorana fermions, such as the hypothetical neutralino, can be described as either a dependent 4-component Majorana spinor or a single 2-component Weyl spinor. It is not known whether the neutrino is a Majorana fermion or a Dirac fermion; observing neutrinoless double-beta decay experimentally would settle this question.
Basic properties
Free (non-interacting) fermionic fields obey canonical anticommutation relations; i.e., involve the anticommutators {a, b} = ab + ba, rather than the commutators [a, b] = ab − ba of bosonic or standard quantum mechanics. Those relations also hold for interacting fermionic fields in the interaction picture, where the fields evolve in time as if free and the effects of the interaction are encoded in the evolution of the states.
It is these anticommutation relations that imply Fermi–Dirac statistics for the field quanta. They also result in the Pauli exclusion principle: two fermionic particles cannot occupy the same state at the same time.
Dirac fields
The prominent example of a spin-1/2 fermion field is the Dirac field (named after Paul Dirac), and denoted by . The equation of motion for a free spin 1/2 particle is the Dirac equation,
where are gamma matrices and is the mass. The simplest possible solutions to this equation are plane wave solutions, and . These plane wave solutions form a basis for the Fourier components of , allowing for the general expansion of the wave function as follows,
u and v are spinors, labelle
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https://en.wikipedia.org/wiki/EDN%20%28magazine%29
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EDN is an electronics industry website and formerly a magazine owned by AspenCore Media, an Arrow Electronics company. The editor-in-chief is Majeed Ahmad. EDN was published monthly until, in April 2013, EDN announced that the print edition would cease publication after the June 2013 issue.
History
The first issue of Electrical Design News, the original name, was published in May 1956 by Rogers Corporation of Englewood, Colorado. In January 1961, Cahners Publishing Company, Inc., of Boston, acquired Rogers Publishing Company. In February 1966, Cahners sold 40% of its company to International Publishing Company in London In 1970, the Reed Group merged with International Publishing Corporation and changed its name to Reed International Limited.
Acquisition of EEE magazine
Cahners Publishing Company acquired Electronic Equipment Engineering, a monthly magazine, in March 1971 and discontinued it. In doing so, Cahners folded EEE's best features into EDN, and renamed the magazine EDN/EEE. At the time, George Harold Rostky (1926–2003) was editor-in-chief of EEE. Rostky joined EDN and eventually became editor-in-chief before leaving to join Electronic Engineering Times as editor-in-chief.
Taking EDN worldwide
Roy Forsberg later became editor-in-chief of EDN magazine. He was later promoted to publisher and Jon Titus PhD was named editor-in-chief. Forsberg and Titus established EDN Europe, EDN Asia and EDN China, creating one of the largest global circulations for a design engineering magazine. EDNs 25th anniversary issue was a 425-page folio.
Reed Limited acquires remaining interest in Cahners
In 1977, Reed acquired the remaining interest in Cahners, then known as Cahners Publications. In 1982, Reed International Limited changed its name to Reed International PLC. In 1992, Reed International merged with Elsevier NV, becoming Reed Elsevier PLC on January 1, 1993. Reed Business Media then removed the Cahners Business Publishing name to rebrand itself as Reed Business Info
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https://en.wikipedia.org/wiki/Ilsemannite
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Ilsemannite is an uncommon amorphous complex heterovalent molybdenum oxide, that was first published in 1871, and has been a valid species since pre-IMA. It is a grandfathered mineral, meaning the name ilsemannite is still believed to refer to a valid species. However, it is likely that specimens formed under different conditions, in different localities do not have the same composition, and may even be a mixture of compounds. Furthermore, it is hard to analyze the specimens due to them being a mixture, hence why adequate analyses are lacking of said mineral. Ilsemannite is believed to be identical to synthetic molybdic oxide.
Properties
Ilsemannite is soluble in water, which at first produces a greenish blue color, which later changes to a deep molybdenum-blue. This is probably why Native Americans believed that ilsemannite colored the waters blue in the Idaho Springs area, however, this has been debunked. Ilsemannite is now believed to consist of molybdenum (66.34%) and oxygen (33.19%), having a negligible amount of hydrogen (0.46%) in it. It has an earthy, dull, clay-like texture, and it is amorphous, meaning ilsemannite does not grow crystals. It does not show any radioactive properties.
In an occurrence near Ouray, Utah, researchers found ilsemannite specimens disseminated through a rock. Analyses showed that about 10% of the sample was water-soluble, and that the water-soluble portion contains iron sulfate. Back then, in 1917, researches concluded that specimens from other localities all showed that iron sulfate was present in each of them, which is why the formula of said mineral was believed to be MoO3·SO3·5H2O. A specimen from Saxony mixed with iron sulfate showed only small amounts of iron, and gave a strong sulfate reaction. Another specimen from Carinthia had the same reaction, however this specimen had only a trace of ferric iron, with no ferrous iron in it. The specimen from Cripple Creek, Colorado showed the exact same reaction.
During a study, it
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https://en.wikipedia.org/wiki/NSA%20cryptography
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The vast majority of the National Security Agency's work on encryption is classified, but from time to time NSA participates in standards processes or otherwise publishes information about its cryptographic algorithms. The NSA has categorized encryption items into four product types, and algorithms into two suites. The following is a brief and incomplete summary of public knowledge about NSA algorithms and protocols.
Type 1 Product
A Type 1 Product refers to an NSA endorsed classified or controlled cryptographic item for classified or sensitive U.S. government information, including cryptographic equipment, assembly or component classified or certified by NSA for encrypting and decrypting classified and sensitive national security information when appropriately keyed.
Type 2 Product
A Type 2 Product refers to an NSA endorsed unclassified cryptographic equipment, assemblies or components for sensitive but unclassified U.S. government information.
Type 3 Product
Unclassified cryptographic equipment, assembly, or component used, when appropriately keyed, for encrypting or decrypting unclassified sensitive U.S. Government or commercial information, and to protect systems requiring protection mechanisms consistent with standard commercial practices. A Type 3 Algorithm refers to NIST endorsed algorithms, registered and FIPS published, for sensitive but unclassified U.S. government and commercial information.
Type 4 Product
A Type 4 Algorithm refers to algorithms that are registered by the NIST but are not FIPS published. Unevaluated commercial cryptographic equipment, assemblies, or components that are neither NSA nor NIST certified for any Government usage.
Algorithm Suites
Suite A
A set of NSA unpublished algorithms that is intended for highly sensitive communication and critical authentication systems.
Suite B
A set of NSA endorsed cryptographic algorithms for use as an interoperable cryptographic base for both unclassified information and most classifie
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https://en.wikipedia.org/wiki/C7orf31
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Chromosome Seven Open Reading Frame 31 (C7orf31) is a protein that in humans is encoded by the C7orf31 gene on chromosome seven.
Gene/Locus
In humans, the C7orf31 gene is located at the locus 7p15.3 and stretches between position 25174316 and 25219817 (span 45502 bp). It codes for at least 4 unique human isoforms: the primary isoform (590 aa; also denoted X1, X2, and CRA_c), isoform X4 (346 aa), isoform CRA_a (580 aa), and isoform CRA_b (380 aa).
Transcript
In humans, C7orf31 codes for an mRNA strand that is 3609 base pairs long. The human mRNA is composed of a 5' untranslated region that is 561 bases and a 3' untranslated region that is 1275 bases long.
Protein
The primary protein encoded by C7orf31 in humans is 590 amino acids long with molecular weight 38334 Da. The protein is part of a functionally uncharacterized family of proteins (pfam15093) with a domain of unknown function (DUF4555).
Protein Orthology
The C7orf31 protein is well-conserved in mammals and birds, but is less conserved in more distant organisms.
C7orf31 does not have any paralogs in humans.
Expression
In humans, C7orf31 is predicted to be localized in the cytosol, nucleus, mitochondrion, and peroxisome, and it is expressed in almost all tissues. It is highly expressed especially in the testes.
Interaction
Two-hybrid studies have found interactions between the proteins encoded by A8K5H9 and C7orf31, and another study has found the protein to interact with KBTBD5.
A study in 2014 found C7orf31 to be a candidate as a centrosome-associated protein, using mass spectrometry on mammalian sperm cells’ centrioles. The protein appears in the study alongside seven other centrosome-associated protein candidates. Along with 2241 other proteins, C7orf31 also exhibited significant binding in a microarray experiment to β-amyloids, a group of proteins associated with Alzheimer's disease. Finally, in a protein-protein interaction network study, C7orf31 was found to associate with KLHL40, whose e
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https://en.wikipedia.org/wiki/Robert%20H.%20Gray
|
Robert Hansen Gray (March 7, 1948 - December 6, 2021) was an American data analyst, author, and astronomer, and author of The Elusive Wow: Searching for Extraterrestrial Intelligence.
Education
Gray attended Shimer College, a Great Books school then located in Mount Carroll, Illinois, where he received a bachelor's degree in 1970. He went on to obtain a master's in urban planning and policy analysis from the University of Illinois at Chicago in 1980.
Career
Data analysis
In 1984, Gray founded the company Gray Data in Chicago, which provided data analysis research services and published reference cards for microcomputer software. He continued to work as a data analyst through his company Gray Consulting.
Search for Extraterrestrial Intelligence (SETI)
Gray is best known for his work as an independent SETI researcher. The Atlantic called Gray "the 'Wow!' signal's most devoted seeker and chronicler, having traveled to the very ends of the earth in search of it."
The Wow! signal was detected by the Ohio State University Radio Observatory (also known as Big Ear) on August 15, 1977. The signal was so pronounced in the data, and so similar to a radio signal rather than a natural source, that SETI scientist Jerry R. Ehman circled it on the computer printout in red ink and wrote "Wow!" next to it. After hearing about the Wow! signal a few years after its detection, Gray contacted the Ohio team, visited Big Ear, and spoke with Ehman, Robert S. Dixon (director of the SETI project) and John D. Kraus (the telescope's designer).
In 1980, Gray began scanning the skies from his backyard in Chicago, using a 12-foot commercial telecommunications dish. He operated his small SETI radio observatory regularly beginning in 1983 and for the next 15 years, but did not find a trace of the Wow! signal. In 1987 and 1989 he led searches for the signal using the Harvard/Smithsonian META radio telescope at the Oak Ridge Observatory in Harvard, Massachusetts. In September 1995 and again in
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https://en.wikipedia.org/wiki/Enema
|
An enema, also known as a clyster, is an injection of fluid into the lower bowel by way of the rectum. The word enema can also refer to the liquid injected, as well as to a device for administering such an injection.
In standard medicine, the most frequent uses of enemas are to relieve constipation and for bowel cleansing before a medical examination or procedure; also, they are employed as a lower gastrointestinal series (also called a barium enema), to treat traveler's diarrhea, as a vehicle for the administration of food, water or medicine, as a stimulant to the general system, as a local application and, more rarely, as a means of reducing body temperature, as treatment for encopresis, and as a form of rehydration therapy (proctoclysis) in patients for whom intravenous therapy is not applicable.
Medical usage
The principal medical usages of enemas are:
Bowel cleansing
Acute treatments
As bowel stimulants, enemas are employed for the same purposes as orally administered laxatives: to relieve constipation; to treat fecal impaction; to empty the colon prior to a medical procedure such as a colonoscopy. When oral laxatives are not indicated or are not sufficiently effective, enemas may be a sensible and necessary measure.
A large volume enema can be given to cleanse as much of the colon as possible of feces. However, a low enema is generally useful only for stool in the rectum, not in the intestinal tract.
Such enemas' mechanism consists of the volume of the liquid causing a rapid expansion of the intestinal tract in conjunction with, in the case of certain solutions, irritation of the intestinal mucosa which stimulates peristalsis and lubricates the stool to encourage a bowel movement. An enema's efficacy depends on several factors including the volume injected and the temperature and the contents of the infusion. In order for the enema to be effective the patient should retain the solution for five to ten minutes, as tolerated. or, as some nursing textboo
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https://en.wikipedia.org/wiki/ViaStreaming
|
ViaStreaming Inc. is a Streaming Media Hosting Provider, as well as a Flash Media Server, SHOUTcast and Windows Media host. They are headquartered out of Jersey City, New Jersey, United States, where a Data Center is operated. The company was founded and opened on November 8, 2004.
ViaStreaming currently owns and operates private racks in 3 different Data Centers (USA-Europe): their multi-homed network is powered by premium Tier 1 network bandwidth featuring diverse path OC-48 fiber connectivity and they partnered with large internet bandwidth providers such as Time Warner Cable, Level3, NTT, AT&T and TeliaSonera using the AOL Bandwidth Internet Backbone, also through several direct peerings. The servers of their content delivery network are each connected to a 10 Gbit/s dedicated switch.
ViaStreaming has grown to over 2,000 users, making them one of the most active audio stream hosts available on the internet. Currently they offer dedicated servers in mp3, Aacplus, Flash Media Server and Windows Media formats in USA and Europe.
ViaStreaming (CrossDigital Ltd.) also owns and operates another brand: ViaMobileApps that develops custom audio & video streaming apps for Smartphones and Tablets mobile devices (Android, iOS, Research In Motion).
As of April 2022, the viastreaming.com website has been indicating certain streaming servers have been down for some weeks, but is not responding to related support requests.
External links
ViaStreaming Home Page
ViaMobileApps Home Page
Internet radio
Video hosting
Streaming
Mobile software development
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https://en.wikipedia.org/wiki/Lanczos%20algorithm
|
The Lanczos algorithm is an iterative method devised by Cornelius Lanczos that is an adaptation of power methods to find the "most useful" (tending towards extreme highest/lowest) eigenvalues and eigenvectors of an Hermitian matrix, where is often but not necessarily much smaller than . Although computationally efficient in principle, the method as initially formulated was not useful, due to its numerical instability.
In 1970, Ojalvo and Newman showed how to make the method numerically stable and applied it to the solution of very large engineering structures subjected to dynamic loading. This was achieved using a method for purifying the Lanczos vectors (i.e. by repeatedly reorthogonalizing each newly generated vector with all previously generated ones) to any degree of accuracy, which when not performed, produced a series of vectors that were highly contaminated by those associated with the lowest natural frequencies.
In their original work, these authors also suggested how to select a starting vector (i.e. use a random-number generator to select each element of the starting vector) and suggested an empirically determined method for determining , the reduced number of vectors (i.e. it should be selected to be approximately 1.5 times the number of accurate eigenvalues desired). Soon thereafter their work was followed by Paige, who also provided an error analysis. In 1988, Ojalvo produced a more detailed history of this algorithm and an efficient eigenvalue error test.
The algorithm
Input a Hermitian matrix of size , and optionally a number of iterations (as default, let ).
Strictly speaking, the algorithm does not need access to the explicit matrix, but only a function that computes the product of the matrix by an arbitrary vector. This function is called at most times.
Output an matrix with orthonormal columns and a tridiagonal real symmetric matrix of size . If , then is unitary, and .
Warning The Lanczos iteration is prone to numerical instability
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https://en.wikipedia.org/wiki/Interstellar%20medium
|
In astronomy, the interstellar medium (ISM) is the matter and radiation that exist in the space between the star systems in a galaxy. This matter includes gas in ionic, atomic, and molecular form, as well as dust and cosmic rays. It fills interstellar space and blends smoothly into the surrounding intergalactic space. The energy that occupies the same volume, in the form of electromagnetic radiation, is the interstellar radiation field. Although the density of atoms in the ISM is usually far below that in the best laboratory vacuums, the mean free path between collisions is short compared to typical interstellar lengths, so on these scales the ISM behaves as a gas (more precisely, as a plasma: it is everywhere at least slightly ionized), responding to pressure forces, and not as a collection of non-interacting particles.
The interstellar medium is composed of multiple phases distinguished by whether matter is ionic, atomic, or molecular, and the temperature and density of the matter. The interstellar medium is composed primarily of hydrogen, followed by helium with trace amounts of carbon, oxygen, and nitrogen. The thermal pressures of these phases are in rough equilibrium with one another. Magnetic fields and turbulent motions also provide pressure in the ISM, and are typically more important, dynamically, than the thermal pressure. In the interstellar medium, matter is primarily in molecular form and reaches number densities of 1012 molecules per m3 (1 trillion molecules per m3). In hot, diffuse regions, gas is highly ionized, and the density may be as low as 100 ions per m3. Compare this with a number density of roughly 1025 molecules per m3 for air at sea level, and 1016 molecules per m3 (10 quadrillion molecules per m3) for a laboratory high-vacuum chamber. By mass, 99% of the ISM is gas in any form, and 1% is dust. Of the gas in the ISM, by number 91% of atoms are hydrogen and 8.9% are helium, with 0.1% being atoms of elements heavier than hydrogen or helium,
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https://en.wikipedia.org/wiki/Apple%20Open%20Directory
|
Apple Open Directory is the LDAP directory service model implementation from Apple Inc. A directory service is software which stores and organizes information about a computer network's users and network resources and which allows network administrators to manage users' access to the resources.
In the context of macOS Server, Open Directory describes a shared LDAPv3 directory domain and a corresponding authentication model composed of Apple Password Server and Kerberos 5 tied together using a modular Directory Services system. Apple Open Directory is a fork of OpenLDAP.
The term Open Directory can also be used to describe the entire directory services framework used by macOS and macOS Server. In this context, it describes the role of a macOS or macOS Server system when it is connected to an existing directory domain, in which context it is sometimes referred to as Directory Services.
Apple, Inc. also publishes an API called the OpenDirectory framework, permitting macOS applications to interrogate and edit the Open Directory data.
With the release of Mac OS X Leopard (10.5), Apple chose to move away from using the NetInfo directory service (originally found in NeXTSTEP and OPENSTEP), which had been used by default for all local accounts and groups in every release of Mac OS X from 10.0 to 10.4. Mac OS X 10.5 now uses Directory Services and its plugins for all directory information. Local accounts are now registered in the Local Plugin, which uses XML property list (plist) files stored in /var/db/dslocal/nodes/Default/ as its backing storage.
Implementation in macOS Server
macOS Server can host an Open Directory domain when configured as an Open Directory Master. In addition to its local directory, this OpenLDAP-based LDAPv3 domain is designed to store centralized management data, user, group, and computer accounts, which other systems can access. The directory domain is paired with the Open Directory Password Server and, optionally, a Kerberos realm. Either p
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https://en.wikipedia.org/wiki/Website%20builder
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Website builders are tools that typically allow the construction of websites without manual code editing. They fall into two categories:
Online proprietary tools provided by web hosting service companies. These are typically intended for service users to build their own website. Some services allow the site owner to use alternative tools (commercial or open-source) — the more complex of these may also be described as content management systems.
Application software software that runs on a personal computing device used to create and edit the pages of a web site and then publish these pages on any host. (These are often considered to be "website design software", rather than "website builders".)
History
The first website, manually written in HTML, was created on August 6, 1991.
Over time, software was created to help design web pages. For example, Microsoft released FrontPage in November 1995.
By 1998, Dreamweaver had been established as the industry leader; however, some have criticized the quality of the code produced by such software as being overblown and reliant on HTML tables. As the industry moved towards W3C standards, Dreamweaver and others were criticized for not being compliant. Compliance has improved over time, but many professionals still prefer to write optimized markup by hand.
Open source tools were typically developed to the standards and made fewer exceptions for the then-dominant Internet Explorer's deviations from the standards.
The W3C started Amaya in 1996 to showcase Web technologies in a fully featured Web client. This was to provide a framework that integrated many W3C technologies in a single, consistent environment. Amaya started as an HTML and CSS editor and now supports XML, XHTML, MathML, and SVG.
GeoCities was one of the first more modern site builders that didn't require any technical skills. Five years after its launch in 1994 Yahoo! purchased it for $3.6 billion. After becoming obsolescent, it was shut down in April 2009.
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https://en.wikipedia.org/wiki/Dwork%20family
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In algebraic geometry, a Dwork family is a one-parameter family of hypersurfaces depending on an integer n, studied by Bernard Dwork. Originally considered by Dwork in the context of local zeta-functions, such families have been shown to have relationships with mirror symmetry and extensions of the modularity theorem.
Definition
The Dwork family is given by the equations
for all .
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https://en.wikipedia.org/wiki/Cauchy%E2%80%93Hadamard%20theorem
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In mathematics, the Cauchy–Hadamard theorem is a result in complex analysis named after the French mathematicians Augustin Louis Cauchy and Jacques Hadamard, describing the radius of convergence of a power series. It was published in 1821 by Cauchy, but remained relatively unknown until Hadamard rediscovered it. Hadamard's first publication of this result was in 1888; he also included it as part of his 1892 Ph.D. thesis.
Theorem for one complex variable
Consider the formal power series in one complex variable z of the form
where
Then the radius of convergence of f at the point a is given by
where denotes the limit superior, the limit as approaches infinity of the supremum of the sequence values after the nth position. If the sequence values are unbounded so that the is ∞, then the power series does not converge near , while if the is 0 then the radius of convergence is ∞, meaning that the series converges on the entire plane.
Proof
Without loss of generality assume that . We will show first that the power series converges for , and then that it diverges for .
First suppose . Let not be or
For any , there exists only a finite number of such that .
Now for all but a finite number of , so the series converges if . This proves the first part.
Conversely, for , for infinitely many , so if , we see that the series cannot converge because its nth term does not tend to 0.
Theorem for several complex variables
Let be a multi-index (a n-tuple of integers) with , then converges with radius of convergence (which is also a multi-index) if and only if
to the multidimensional power series
The proof can be found in
Notes
External links
Augustin-Louis Cauchy
Mathematical series
Theorems in complex analysis
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https://en.wikipedia.org/wiki/Peristimulus%20time%20histogram
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In neurophysiology, peristimulus time histogram and poststimulus time histogram, both abbreviated PSTH or PST histogram, are histograms of the times at which neurons fire. It is also sometimes called pre event time histogram or PETH. These histograms are used to visualize the rate and timing of neuronal spike discharges in relation to an external stimulus or event. The peristimulus time histogram is sometimes called perievent time histogram, and post-stimulus and peri-stimulus are often hyphenated.
The prefix peri, for through, is typically used in the case of periodic stimuli, in which case the PSTH show neuron firing times wrapped to one cycle of the stimulus. The prefix post is used when the PSTH shows the timing of neuron firings in response to a stimulus event or onset.
To make a PSTH, a spike train recorded from a single neuron is aligned with the onset, or a fixed phase point, of an identical stimulus repeatedly presented to an animal. The aligned sequences are superimposed in time, and then used to construct a histogram.
Construction procedure
Align spike sequences with the onset of a stimulus that is repeated n times. For periodic stimuli, wrap the response sequence back to time zero after each time period T, and count n as the total number of periods of data.
Divide the stimulus period or observation period T into N bins of size .
Count the number of spikes ki from all n sequences that fall in the bin i.
Draw a bar-graph histogram with the bar-height of bin i given by in units of estimated spikes per second at time .
The optimal bin size (assuming an underlying Poisson point process) Δ is a minimizer of the formula, (2k-v)/Δ2,
where k and v are mean and variance of ki.
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https://en.wikipedia.org/wiki/Link%20Motion%20Inc
|
Link Motion Inc, formerly NetQin and NQ Mobile, is a multinational technology company that develops, licenses, supports and sells software and services that focus on the smart ride business. Link Motion sells carputers for car businesses, consumer ride sharing services, as well as legacy mobile security, productivity and other related applications. Link Motion maintains dual headquarters in Dallas, Texas, United States and Beijing, China. A Court Receiver, lawyer Robert Seiden, was appointed over Link Motion in February 2019 in the United States in the federal district court in the Southern District of New York by Judge Victor Marrero. The Receiver removed Wenyong “Vincent” Shi as chairman and chief executive officer, and replaced him by appointing Mr. Lilin “Francis” Guo.
History
2005–2011: Founding and company beginnings
Link Motion was founded as NQ Mobile in 2005 by Dr. Henry Lin, formerly the youngest associate professor at the Beijing University of Posts and Telecommunications, and Dr. Vincent Shi. The company began its business by offering mobile security services and later started offering productivity products to families and enterprise customers. Their services were compatible with a wide range of handset models and almost all currently available operating systems for smartphones, including iOS, Android, Windows Phone and BlackBerry OS. NQ Mobile also collaborated closely with other mobile ecosystem participants, including chipmakers, handset manufacturers, wireless carriers, third party payment channels, retailers and other distribution channels in order to broaden the reach of their services.
NQ Mobile's initial focus was the China marketplace. The company cooperated with China Mobile, China Unicom and China Telecom, the three largest mobile companies in China. NQ Mobile also cooperated with Nokia and Sony to pre-installed NQ products on their companywide mobile phones. NQ Mobile has also worked closely with Symbian, Windows Mobile and Android, devel
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https://en.wikipedia.org/wiki/Simon%E2%80%93Glatzel%20equation
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The Simon–Glatzel equation is an empirical correlation describing the pressure dependence of the melting temperature of a solid. The pressure dependence of the melting temperature is small for small pressure changes because the volume change during fusion or melting is rather small. However, at very high pressures higher melting temperatures are generally observed as the liquid usually occupies a larger volume than the solid making melting more thermodynamically unfavorable at elevated pressure. If the liquid has a smaller volume than the solid (as for ice and liquid water) a higher pressure leads to a lower melting point.
The equation and its variations
and are normally the temperature and the pressure of the triple point, but the normal melting temperature at atmospheric pressure are also commonly used as reference point because the normal melting point is much more easily accessible. Typically is then set to 0. and are component-specific parameters.
The Simon–Glatzel equation can be viewed as a combination of the Murnaghan equation of state and the Lindemann law, and an alternative form was proposed by J. J. Gilvarry (1956):
where is general at , is pressure derivative at , is Grüneisen ratio, and is the coefficient in Morse potential.
Example parameters
For methanol the following parameters can be obtained:
The reference temperature has been Tref = 174.61 K and the reference pressure Pref has been set to 0 kPa.
Methanol is a component where the Simon–Glatzel works well in the given validity range.
Extensions and generalizations
The Simon–Glatzel equation is a monotonically increasing function. It can only describe the melting curves that rise indefinitely with increasing pressure. It may fail to describe the melting curves with a negative pressure dependence or local maximums. A damping term that asymptotically slopes down under pressure, (c is another component-specific parameter), is introduced by Vladimir V. Kechin to extend the Sim
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https://en.wikipedia.org/wiki/45th%20meridian%20east
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The meridian 45° east of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, Europe, Asia, Africa, the Indian Ocean, the Southern Ocean, and Antarctica to the South Pole.
The 45th meridian east forms a great circle with the 135th meridian west. The meridian is the mid point of the Moscow Time.
From Pole to Pole
Starting at the North Pole and heading south to the South Pole, the 45th meridian east passes through:
{| class="wikitable plainrowheaders"
! scope="col" width="115" | Co-ordinates
! scope="col" | Country, territory or sea
! scope="col" | Notes
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| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Arctic Ocean
| style="background:#b0e0e6;" |
|-
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! scope="row" |
| Island of Alexandra Land
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| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Barents Sea
| style="background:#b0e0e6;" |
|-
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! scope="row" |
| Kanin Peninsula
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Barents Sea
| style="background:#b0e0e6;" | Chesha Bay
|-
|
! scope="row" |
| Passing through Penza
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! scope="row" |
|Passing through Tbilisi
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! scope="row" |
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|-
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! scope="row" |
| Yukhari Askipara exclave surrounded by
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! scope="row" |
| Passing through Lake Sevan
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! scope="row" |
| Nakhchivan exclave
|-
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! scope="row" |
| Passing just west of Urmia
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! scope="row" |
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|-
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! scope="row" |
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|-
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! scope="row" |
| Passing just west of Aden (at )
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Indian Ocean
| style="background:#b0e0e6;" | Gulf of Aden
|-
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! scope="row" |
| Somaliland - passing just east of Berbera
|-
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! scope="row" |
|
|-
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! scope="row" |
|
|-valign="top"
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Indian Ocean
| style="background:#b0e0e6;" | Passing just west of Mayotte, an overseas department of
|-
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! scope="row" |
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|-
| style=
|
https://en.wikipedia.org/wiki/Palatine%20bone
|
In anatomy, the palatine bones () are two irregular bones of the facial skeleton in many animal species, located above the uvula in the throat. Together with the maxillae, they comprise the hard palate. (Palate is derived from the Latin palatum.)
Structure
The palatine bones are situated at the back of the nasal cavity between the maxilla and the pterygoid process of the sphenoid bone.
They contribute to the walls of three cavities: the floor and lateral walls of the nasal cavity, the roof of the mouth, and the floor of the orbits. They help to form the pterygopalatine and pterygoid fossae, and the inferior orbital fissures.
Each palatine bone somewhat resembles the letter L, and consists of a horizontal plate, a perpendicular plate, and three projecting processes—the pyramidal process, which is directed backward and lateral from the junction of the two parts, and the orbital and sphenoidal processes, which surmount the vertical part, and are separated by a deep notch, the sphenopalatine notch. The two plates form the posterior part of the hard palate and the floor of the nasal cavity; anteriorly, they join with the maxillae. The two horizontal plates articulate with each other at the posterior part of the median palatine suture and more anteriorly with the maxillae at the transverse palatine suture.
The human palatine articulates with six bones: the sphenoid, ethmoid, maxilla, inferior nasal concha, vomer and opposite palatine.
There are two important foramina in the palatine bones that transmit nerves and blood vessels to this region: the greater and lesser palatine. The larger greater palatine foramen is located in the posterolateral region of each of the palatine bones, usually at the apex of the maxillary third molar. The greater palatine foramen transmits the greater palatine nerve and blood vessels. A smaller opening nearby, the lesser palatine foramen, transmits the lesser palatine nerve and blood vessels to the soft palate and tonsils. Both foramina ar
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https://en.wikipedia.org/wiki/512-bit%20computing
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There are currently no mainstream general-purpose processors built to operate on 512-bit integers or addresses, though a number of processors do operate on 512-bit data.
Representation
A 512-bit register can store 2512 different values. The range of integer values that can be stored in 512 bits depends on the integer representation used.
The maximum value of an unsigned 512-bit integer is 2512 − 1, written in decimal as 13,407,807,929,942,597,099,574,024,998,205,846,127,479,365,820,592,393,377,723,561,443,721,764,030,073,546,976,801,874,298,166,903,427,690,031,858,186,486,050,853,753,882,811,946,569,946,433,649,006,084,095 or approximately 1.34078 x 10154, or textualized as over 13.407 Quinquagintillion.
Hardware
The Intel Xeon Phi has a vector processing unit with 512-bit vector registers, each one holding sixteen 32-bit elements or eight 64-bit elements, and one instruction can operate on all these values in parallel. However, the Xeon Phi's vector processing unit does not operate on individual numbers that are 512 bits long.
Some GPUs such as the Advanced Micro Devices (AMD) Radeon HD 2900XT, the Nvidia GTX 280, GTX 285, Quadro FX 5800 and several Nvidia Tesla products move data across a 512-bit memory bus. Then AMD Radeon R9 290, R9 290X and 295X2 followed.
AVX-512 are 512-bit extensions to the 256-bit Advanced Vector Extensions SIMD instructions for x86 instruction set architecture proposed by Intel in July 2013, and released on 2016 with Knights Landing, and in 2017 on the HEDT and consumer server platform, with Skylake-X and Skylake-SP respectively.
Software
Many hash functions, such as SHA-512 and SHA3-512, have a 512-bit output.
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https://en.wikipedia.org/wiki/Duivenbode%27s%20riflebird
|
Duivenbode's riflebird is a bird in the family Paradisaeidae that is a presumed intergeneric hybrid between a magnificent riflebird and lesser lophorina. The common name commemorates Maarten Dirk van Renesse van Duivenbode (1804-1878), Dutch trader of naturalia on Ternate.
History
Three adult male specimens are recorded of this hybrid: one each in the American Museum of Natural History and British Natural History Museum; the third type specimen in the Dresden Natural History Museum was destroyed in World War II. They derive from the area inland of Yule Island in south-eastern New Guinea, not far from Port Moresby.
Notes
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https://en.wikipedia.org/wiki/Speedeez
|
Speedeez was a micro-scale toy car brand produced by Playmates Toys from 2002 to 2005. It made little toy cars from all of the brands.
Vehicles
The majority of models is roughly 1.5 inches in length (scale 1:100). They consist of a plastic die-cast, hand-painted body and a plastic baseplate with a steel ball in the middle. The base plate is connected to the body via two rivets, philips screws or tri-angle screws (depending on the release type). Six vehicles were released as a glow-in-the-dark version. The steel ball adds weight to the car and makes it able to drift.
Some of the released vehicles are licensed by their respective car brand, which is reflected on the blister backing cards. The most prominent makes are Chevrolet, Chrysler, Dodge, Ford and Jeep. Some featured models have never been released in micro scale before, including the Jeep Jeepster, the Chrysler PT Cruiser, the Audi TT, the BMW Z3, the BMW Mini or the Dodge SRT-4. Some vehicles use the same moulds as Charm Max and Tamfort (Turbo Ball Racers) or are heavily inspired by Micro Machines and Funrise Micro Magnifier models.
Distribution
Vehicles were distributed in various blister packs and included with playsets during the production run. The packaging was designed by Bill Ticineto of Go Dog Design Group, LLC.
Playsets
Speedeez also released playsets.
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https://en.wikipedia.org/wiki/The%20Farm%20of%20Tomorrow
|
The Farm of Tomorrow is a 1954 one-reel animated short subject directed by Tex Avery and produced by Fred Quimby. It was released theatrically with the feature filmmovie Rogue Cop on 18 September 1954 and distributed by Metro-Goldwyn-Mayer.
This cartoon is one of Avery's future technology cartoons including The House of Tomorrow, The Car of Tomorrow and T.V. of Tomorrow.
Summary
The narrator (voiced by Paul Frees) introduces the Farm of Tomorrow, a wonderland of modern and mechanical inventions together with the advanced scientifically-improved livestock.
A series of gags showing how much more productive farms would be if farmers started crossbreeding their animals to create weird (but very useful) hybrids.
Each of the inventions and hybrids are explained:
In the old days, hatching eggs would take 3 weeks. A toaster-like incubator that hatches chicks requires only a few seconds. Set it to dark and the chicks come up black. It is mentioned that caution should be used in setting the selector.
Another problem in the old days would be the grading of eggs for size. A pinball machine-like egg grader was created for this purpose. One small egg rolls through the machine and hatches a small chick who runs back inside the machine calling for his mom.
Picking up corn used to waste vast amounts of energy. A corn was crossed with Mexican jumping beans; they jump directly into the chicken's mouth.
A chicken was crossed with a talking parrot, with the result that the hybrid (voiced by June Foray) lays an egg and shouts "Come and get it!"
A chicken was crossed with an ostrich to provide bigger drumsticks.
A chicken was crossed with a centipede to get more drumsticks.
To increase egg production, a chicken was crossed with a slot machine. A farmer lifts the chicken's left wing and eggs are released, which the farmer collects.
To guarantee absolute freshness in every egg, a full-proof Smell-O-Meter was created. A rotten egg is detected and discarded. It subsequently hatch
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https://en.wikipedia.org/wiki/Serositis
|
Serositis refers to inflammation of the serous tissues of the body, the tissues lining the lungs (pleura), heart (pericardium), and the inner lining of the abdomen (peritoneum) and organs within. It is commonly found with fat wrapping or creeping fat.
Causes
Serositis is seen in numerous conditions:
Lupus erythematosus (SLE), for which it is one of the criteria,
Rheumatoid arthritis
Familial Mediterranean fever (FMF)
Chronic kidney failure / Uremia
Juvenile idiopathic arthritis
Inflammatory bowel disease (especially Crohn's disease)
Acute appendicitis
Diffuse cutaneous systemic sclerosis
See also
Hyaloserositis
|
https://en.wikipedia.org/wiki/Essential%20fatty%20acid%20interactions
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There are many fatty acids found in nature. The two essential fatty acids are omega-3 and omega-6, which are necessary for good human health. However, the effects of the ω-3 (omega-3) and ω-6 (omega-6) essential fatty acids (EFAs) are characterized by their interactions. The interactions between these two fatty acids directly effect the signaling pathways and biological functions like inflammation, protein synthesis, neurotransmitters in our brain, and metabolic pathways in the human body.
Arachidonic acid (AA) is a 20-carbon omega-6 essential fatty acid. It sits at the head of the "arachidonic acid cascade," which initiates 20 different signaling paths that control a wide array of biological functions, including inflammation, cell growth, and the central nervous system. Most AA in the human body is derived from dietary linoleic acid (18:2 ω-6), which is found in nuts, seeds, vegetable oils, and animal fats.
During inflammation, two other groups of dietary essential fatty acids form cascade that compete with the arachidonic acid cascade. EPA (20:5 ω-3) provides the most important competing cascade. EPA is ingested from oily fish, algae oil, or alpha-linolenic acid (derived from walnuts, hemp oil, and flax oil). DGLA (20:3 ω-6) provides a third, less prominent cascade. It is derived from dietary GLA (18:3 ω-6) found in borage oil. These two parallel cascades soften the inflammatory-promoting effects of specific eicosanoids made from AA.
The diet from a century ago had much less ω-3 than the diet of early hunter-gatherers but also much less pollution than today, which evokes the inflammatory response. We can also look at the ratio of ω-3 to ω-6 in comparison with their diets. These changes have been accompanied by increased rates of many diseases—the so-called diseases of civilization—that involve inflammatory processes. There is now very strong evidence that several of these diseases are ameliorated by increasing dietary ω-3. There is also more preliminary eviden
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https://en.wikipedia.org/wiki/Magnetic%20resonance%20%28quantum%20mechanics%29
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In quantum mechanics, magnetic resonance is a resonant effect that can appear when a magnetic dipole is exposed to a static magnetic field and perturbed with another, oscillating electromagnetic field. Due to the static field, the dipole can assume a number of discrete energy eigenstates, depending on the value of its angular momentum (azimuthal) quantum number. The oscillating field can then make the dipole transit between its energy states with a certain probability and at a certain rate. The overall transition probability will depend on the field's frequency and the rate will depend on its amplitude. When the frequency of that field leads to the maximum possible transition probability between two states, a magnetic resonance has been achieved. In that case, the energy of the photons composing the oscillating field matches the energy difference between said states. If the dipole is tickled with a field oscillating far from resonance, it is unlikely to transition. That is analogous to other resonant effects, such as with the forced harmonic oscillator. The periodic transition between the different states is called Rabi cycle and the rate at which that happens is called Rabi frequency. The Rabi frequency should not be confused with the field's own frequency. Since many atomic nuclei species can behave as a magnetic dipole, this resonance technique is the basis of nuclear magnetic resonance, including nuclear magnetic resonance imaging and nuclear magnetic resonance spectroscopy.
Quantum mechanical explanation
As a magnetic dipole, using a spin system such as a proton; according to the quantum mechanical state of the system, denoted by : , evolved by the action of a unitary operator ; the result obeys Schrödinger equation:
States with definite energy evolve in time with phase ,( ) where E is the energy of the state, since the probability of finding the system in state = is independent of time. Such states are termed stationary states,
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https://en.wikipedia.org/wiki/Human%20action%20cycle
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The human action cycle is a psychological model which describes the steps humans take when they interact with computer systems. The model was proposed by Donald A. Norman, a scholar in the discipline of human–computer interaction. The model can be used to help evaluate the efficiency of a user interface (UI). Understanding the cycle requires an understanding of the user interface design principles of affordance, feedback, visibility and tolerance.
The human action cycle describes how humans may form goals and then develop a series of steps required to achieve that goal, using the computer system. The user then executes the steps, thus the model includes both cognitive activities and physical activities.
The three stages of the human action cycle
The model is divided into three stages of seven steps in total, and is (approximately) as follows:
Goal formation stage
1. Goal formation.
Execution stage
2. Translation of goals into a set of unordered tasks required to achieve goals.
3. Sequencing the tasks to create the action sequence.
4. Executing the action sequence.
Evaluation stage
5. Perceiving the results after having executed the action sequence.
6. Interpreting the actual outcomes based on the expected outcomes.
7. Comparing what happened with what the user wished to happen.
Use in evaluation of user interfaces
Typically, an evaluator of the user interface will pose a series of questions for each of the cycle's steps, an evaluation of the answer provides useful information about where the user interface may be inadequate or unsuitable. These questions might be:
Step 1, Forming a goal:
Do the users have sufficient domain and task knowledge and sufficient understanding of their work to form goals?
Does the UI help the users form these goals?
Step 2, Translating the goal into a task or a set of tasks:
Do the users have sufficient domain and task knowledge and sufficient understanding of their work to formulate the tasks?
Does the UI help
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https://en.wikipedia.org/wiki/Derjaguin%20approximation
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The Derjaguin approximation (or sometimes also referred to as the proximity approximation), named after the Russian scientist Boris Derjaguin, expresses the force profile acting between finite size bodies in terms of the force profile between two planar semi-infinite walls. This approximation is widely used to estimate forces between colloidal particles, as forces between two planar bodies are often much easier to calculate. The Derjaguin approximation expresses the force F(h) between two bodies as a function of the surface separation as
where W(h) is the interaction energy per unit area between the two planar walls and Reff the effective radius. When the two bodies are two spheres of radii R1 and R2, respectively, the effective radius is given by
Experimental force profiles between macroscopic bodies as measured with the surface forces apparatus (SFA) or colloidal probe technique are often reported as the ratio F(h)/Reff.
Quantities involved and validity
The force F(h) between two bodies is related to the interaction free energy U(h) as
where h is the surface-to-surface separation. Conversely, when the force profile is known, one can evaluate the interaction energy as
When one considers two planar walls, the corresponding quantities are expressed per unit area. The disjoining pressure is the force per unit area and can be expressed by the derivative
where W(h) is the surface free energy per unit area. Conversely, one has
The main restriction of the Derjaguin approximation is that it is only valid at distances much smaller than the size of the objects involved, namely h ≪ R1 and h ≪ R2. Furthermore, it is a continuum approximation and thus valid at distances larger than the molecular length scale. Even when rough surfaces are involved, this approximation has been shown to be valid in many situations. Its range of validity is restricted to distances larger than the characteristic size of the surface roughness features (e.g., root mean square roughness).
Speci
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https://en.wikipedia.org/wiki/Luquillo%20Experimental%20Forest
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The Luquillo Experimental Forest (Bosque experimental de Luquillo) is a protected area of tropical rainforest in northeastern Puerto Rico. The experimental forest is located in the Sierra de Luquillo some east of San Juan, the capital of the island. It is a UNESCO Biosphere Reserve and is used for research into silviculture, forest regeneration, and other purposes.
History
The Tropical Forest Research Station was founded in 1940 and became a center for ecosystem research. It was designated as a UNESCO Biosphere Reserve in 1976 with the objective of understanding "the long-term dynamics of tropical forest ecosystems characterized by large-scale, infrequent disturbance, rapid processing of organic material, and high habitat and species diversity".
Although the experimental forest is located within El Yunque National Forest, the two have different objectives. In a forest management plan drawn up in 1956, approximately were to be used for commercial timber production, mostly the lower, flatter part of the site. The remaining , largely mountain peaks and steep slopes, were considered non-commercial and were set aside for research and other purposes. Much of the experimental area is used for silviculture and reforestation research, however certain areas have been left completely unmanaged, and are of global importance for use in long term ecological studies.
The experimental forest is one of 26 sites run by the Long Term Ecological Research Network, a group of international scientists studying ecological processes over long time scales. The facility was established in 1988 to study the "long-term effects of natural and human disturbances on tropical forests and streams in the Luquillo mountains". The aspects studied include how hurricanes and droughts have affected the environment, and the effects of changes in agricultural practices and increased urbanization. A central database is maintained, collaboration between scientists, students and volunteers is encouraged,
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https://en.wikipedia.org/wiki/Display%20driver
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In electronics/computer hardware, a display driver is usually a semiconductor integrated circuit (but may alternatively comprise a state machine made of discrete logic and other components) which provides an interface function between a microprocessor, microcontroller, ASIC or general-purpose peripheral interface and a particular type of display device, e.g. LCD, LED, OLED, ePaper, CRT, Vacuum fluorescent or Nixie.
The display driver will typically accept commands and data using an industry-standard general-purpose serial or parallel interface, such as TTL, CMOS, RS-232, SPI, I2C, etc. and generate signals with suitable voltage, current, timing and demultiplexing to make the display show the desired text or image.
The display driver may itself be an application-specific microcontroller and may incorporate RAM, Flash memory, EEPROM and/or ROM. Fixed ROM may contain firmware and display fonts.
A notable example of a display driver IC is the Hitachi HD44780 LCD controller.
Other controllers are KS0108, SSD1815 (graphics capable) and ST7920 (graphics capable)
History
The use of integrated circuit technology to drive a display driver chip dates back to the late 1960s. In 1969, Hewlett-Packard introduced the HP Model 5082-7000 Numeric Indicator, an early LED display and the first LED device to use integrated circuit technology. Its development was led by Howard C. Borden and Gerald P. Pighini at HP Associates and HP Labs, who had engaged in research and development (R&D) on practical LEDs between 1962 and 1968. It was the first intelligent LED display, making it a revolution in digital display technology, replacing the Nixie tube and becoming the basis for later LED displays.
In the early 21st century, display driver chips are widely used for mobile displays in smartphones and other smart devices as well as larger flat-panel displays. Between 2003 and 2005, LCD display driver chips sold 9,821.2million units worldwide.
See also
Device driver
Printer driver
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https://en.wikipedia.org/wiki/1985%E2%80%931987%20Watsonville%20Cannery%20strike
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The 1985–1987 Watsonville Cannery strike was a labor strike that involved over 1,000 workers at two food processing facilities in Watsonville, California, United States. The facilities were owned by Watsonville Canning and Richard A. Shaw Inc., two of the largest frozen food processors in the United States, while the workers were all union members of the International Brotherhood of Teamsters (IBT) Local 912. The strike began on September 9, 1985, and completely ended about 18 months later, on March 11, 1987.
The city of Watsonville has historically been a center for the food processing industry in California, and by the mid-1900s, it had branded itself as the "frozen food capital of the world", with eight frozen food processing plants in the city. These plants were in an industry-wide labor contract with IBT Local 912, who represented several thousand employees in the city. By the 1980s, due to an increase in migration from Mexico, a large number of these food processing workers were Latinos. Around that same time, changes in the food processing industry caused the Watsonville plants to become less profitable, and in 1982, Watsonville Canning (the single-largest frozen food processor in the United States) negotiated an hourly wage decrease for their union employees from $7.06 to $6.66. In 1985, their labor contract had expired, and Watsonville Canning began pushing for further wage and employee benefits reductions. Richard A. Shaw Inc., another major food processing company in the city, similarly began requesting wage and benefits reductions, which were opposed by the local union. On September 9, union members from both companies began a strike, with picketing commencing shortly thereafter.
The strike received significant support from the local Latino community, with support coming from Chicano and Hispanic organizations such as the League of United Latin American Citizens and the Mexican American Political Association. Additionally, civil rights leaders Cesar Ch
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https://en.wikipedia.org/wiki/Structural%20stability
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In mathematics, structural stability is a fundamental property of a dynamical system which means that the qualitative behavior of the trajectories is unaffected by small perturbations (to be exact C1-small perturbations).
Examples of such qualitative properties are numbers of fixed points and periodic orbits (but not their periods). Unlike Lyapunov stability, which considers perturbations of initial conditions for a fixed system, structural stability deals with perturbations of the system itself. Variants of this notion apply to systems of ordinary differential equations, vector fields on smooth manifolds and flows generated by them, and diffeomorphisms.
Structurally stable systems were introduced by Aleksandr Andronov and Lev Pontryagin in 1937 under the name "systèmes grossiers", or rough systems. They announced a characterization of rough systems in the plane, the Andronov–Pontryagin criterion. In this case, structurally stable systems are typical, they form an open dense set in the space of all systems endowed with appropriate topology. In higher dimensions, this is no longer true, indicating that typical dynamics can be very complex (cf. strange attractor). An important class of structurally stable systems in arbitrary dimensions is given by Anosov diffeomorphisms and flows. During the late 1950s and the early 1960s, Maurício Peixoto and Marília Chaves Peixoto, motivated by the work of Andronov and Pontryagin, developed and proved Peixoto's theorem, the first global characterization of structural stability.
Definition
Let G be an open domain in Rn with compact closure and smooth (n−1)-dimensional boundary. Consider the space X1(G) consisting of restrictions to G of C1 vector fields on Rn that are transversal to the boundary of G and are inward oriented. This space is endowed with the C1 metric in the usual fashion. A vector field F ∈ X1(G) is weakly structurally stable if for any sufficiently small perturbation F1, the corresponding flows are topologically
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https://en.wikipedia.org/wiki/In%20Pursuit%20of%20the%20Traveling%20Salesman
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In Pursuit of the Traveling Salesman: Mathematics at the Limits of Computation is a book on the travelling salesman problem, by William J. Cook, published in 2011 by the Princeton University Press, with a paperback reprint in 2014. The Basic Library List Committee of the Mathematical Association of America has suggested its inclusion in undergraduate mathematics libraries.
Topics
The travelling salesman problem asks to find the shortest cyclic tour of a collection of points, in the plane or in more abstract mathematical spaces.
Because the problem is NP-hard, algorithms that take polynomial time are unlikely to be guaranteed to find its optimal solution; on the other hand a brute-force search of all permutations would always solve the problem exactly but would take far too long to be usable for all but the smallest problems. Threading a middle ground between these too-fast and too-slow running times, and developing a practical system that can find the exact solution of larger instances, raises difficult questions of algorithm engineering, which have sparked the development of "many of the concepts and techniques of combinatorial optimization".
The introductory chapter of the book explores the limits of calculation on the problem, from 49-point problems solved by hand in the mid-1950s by George Dantzig, D. R. Fulkerson, and Selmer M. Johnson to a problem with 85,900 points solved optimally in 2006 by the Concorde TSP Solver, which Cook helped develop. The next chapters covers the early history of the problem and of related problems, including Leonhard Euler's work on the Seven Bridges of Königsberg, William Rowan Hamilton's Icosian game, and Julia Robinson first naming the problem in 1949. Another chapter describes real-world applications of the problem, ranging "from genome sequencing and designing computer processors to arranging music and hunting for planets". Reviewer Brian Hayes cites "the most charming revelation" of the book as being the fact that one of tho
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https://en.wikipedia.org/wiki/IAP%20statement%20on%20population%20growth
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The InterAcademy Panel Statement on Population Growth is an international scientist consensus document discussing and demanding a halt of the population expansion. This was the first worldwide joint statement of academies of sciences, and their cooperative InterAcademy Panel on International Issues. It was signed by 58 member academies and began as follows.
Let 1994 be remembered as the year when the people of the world decided to act together for the benefit of future generations.
Background
Between October 24 and October 27, 1993, an international "scientist's top summit" was held in New Delhi, India, with representatives from academies of sciences from all over the world. This grew out of two previous meetings, one joint meeting by the British Royal Society and the United States National Academy of Sciences, and one international meeting organised by the Royal Swedish Academy of Sciences. The scientists discussed the environmental and social welfare problems for the world population, and found them closely linked to the population expansion.
In the year 1950, there were approximately 2.5 billion (2,500 million) humans alive in this world. By 1960, the number had reached 3 billion, and by 1975 was at 4 billion. The 5 billion mark was reached around 1987, and in 1993, at the New Delhi meeting, academics estimated the population to be 5.5 billion. For some time, world food production had been able to roughly match population growth, meaning that starvation was a regional and distributional problem, rather than one based on a total shortage of food. The scientists noted that increased food production on land and on sea in the previous decade was less than the population increase over the same period. Moreover, by increased food production and otherwise, the population growth was contributing to a loss of biodiversity, deforestation and loss of topsoil, and shortages of water and fuel. The academics noted that the complex relationships between population size and
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https://en.wikipedia.org/wiki/Barrel%20of%20oil%20equivalent
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The barrel of oil equivalent (BOE) is a unit of energy based on the approximate energy released by burning one barrel (, or ) of crude oil. The BOE is used by oil and gas companies in their financial statements as a way of combining oil and natural gas reserves and production into a single measure, although this energy equivalence does not take into account the lower financial value of energy in the form of gas.
The U.S. Internal Revenue Service defines a BOE as equal to 5.8 million BTU. (, about [HHV], or about .) The value is necessarily approximate as various grades of oil and gas have slightly different heating values. If one considers the lower heating value instead of the higher heating value, the value for one BOE would be approximately 5.4 GJ (see tonne of oil equivalent). Typically or 58 CCF are equivalent to one BOE. The USGS gives a figure of of typical natural gas.
A commonly used multiple of the BOE is the kilo barrel of oil equivalent (kboe or kBOE), which is 1,000 BOE. This should be avoided because it might lead to the use of MBOE (mega barrel of oil equivalent) but MBOE actually means thousand BOE. This potential confusion arises due to the use of Roman numeral M (one thousand) for natural gas production and MM (one million, even though MM means two thousand). In the S.I. (metric system) M means million, but cubic feet and barrels are not S.I. units, so S.I. prefixes should not be used. Another commonly used multiple is million barrels eqivalent per day, MMboed (or MMBOED, MMboepd, where MM denotes a million), used to measure daily production and consumption, and the BBOe (also BBOE) or billion barrels of oil equivalent, representing 109 barrels of oil, used to measure petroleum reserves.
Metric regions commonly use the tonne of oil equivalent (toe), or more often million toe (Mtoe). Since this is a measurement of mass, any conversion to barrels of oil equivalent depends on the density of the oil in question, as well as the energy content. Ty
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https://en.wikipedia.org/wiki/Lunar%20Atmospheric%20Composition%20Experiment
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The Lunar Atmospheric Composition Experiment (LACE) was a miniature magnetic deflection mass spectrometer (neutral mass spectrometer). The experiment's aim was to study the composition and variations of the lunar atmosphere. The only deployment of LACE was as part of the Apollo Lunar Surface Experiments Package (ALSEP) on Apollo 17 within the Taurus–Littrow valley.
LACE was a follow-on to the Cold Cathode Gauges that were flown on Apollo 14 and Apollo 15. Those experiments proved the existence of a tenuous lunar atmosphere and determined the upper bounds on the lunar atmospheric density during the lunar day and night, but left its composition unknown.
Instrument
As gas molecules enter the experiment's aperture, they are ionised by electron bombardment. These gas ions are then collimated into a beam and passed through a magnetic analyser to the detector. The electron-ion sources consist of two filaments, composed of 99% tungsten and 1% rhenium. Multiple ion mass-ranges could be scanned simultaneously by varying the voltage across the electron-ion source. Each mass range had an independent system for counting ions. Each system consisted of an electron multiplier, pulse amplifier, discriminator and counter. The experiment could detect ions of 28 and 64 atomic mass units at the same time, enabling the simultaneous measurement of carbon monoxide and sulphur dioxide.
LACE's instrument recording accuracy remained at 1% for all 21-bit counts. During calibration of the instrument, it was discovered that ion flux, hitting the detector at over , resulted in saturation of the counter.
Deployment and operation
LACE was deployed by the Apollo 17 astronauts on 12 December 1972, at roughly 05:00 UTC. The entrance aperture was deployed upwards to measure the downward flux of gases at the lunar surface. A nylon dust screen covered the upward-facing aperture to protect it during mission surface activities. This dust screen was pulled back by radio command after the crew had ta
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https://en.wikipedia.org/wiki/Institute%20for%20Mathematical%20Research
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The Institute for Mathematical Research (Forschungsinstitut für Mathematik, FIM) is a mathematical research institution located at ETH Zurich and founded in 1964 by Beno Eckmann. Its main goals are to promote and facilitating the exchange between ETH Zurich and international leading mathematicians.
The Institute offers a platform on which contacts of lasting values between faculty members of the Department of Mathematics of ETH, graduate students, members of the Swiss mathematical community at large and international researchers can be established. A lean staff structure of a director, a coordinator and an administrative assistant, a well-equipped infrastructure of 30 working spaces, and an independent budget serve as the basis of the Institute.
This structure enables the FIM to host about 200 guests per year, ranging from short term visits of one or two days to long term stays of up to one year. Furthermore, the FIM organises scientific activities like conferences, minicourses and advanced graduate courses.
FIM is member of ERCOM (European Research Centres on Mathematics) and is the SNF and ETH Zurich.
List of directors
2019–present Alessio Figalli
2009–2019 Tristan Rivière
1999–2009 Marc Burger
1995–1999 Alain-Sol Sznitman
1984–1995 Jürgen Moser
1964–1984 Beno Eckmann
Advisory board
Internal Advisory Board: Rahul Pandharipande, Alain-Sol Sznitman, Rico Zenklusen
External Advisory Board: Viviane Baladi, Martin Hairer, Akshay Venkatesh, Cédric Villani
Guests
FIM maintains an online list of the present and scheduled guests at the institute.
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https://en.wikipedia.org/wiki/Kulkarni%E2%80%93Nomizu%20product
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In the mathematical field of differential geometry, the Kulkarni–Nomizu product (named for Ravindra Shripad Kulkarni and Katsumi Nomizu) is defined for two -tensors and gives as a result a -tensor.
Definition
If h and k are symmetric -tensors, then the product is defined via:
where the Xj are tangent vectors and is the matrix determinant. Note that , as it is clear from the second expression.
With respect to a basis of the tangent space, it takes the compact form
where denotes the total antisymmetrisation symbol.
The Kulkarni–Nomizu product is a special case of the product in the graded algebra
where, on simple elements,
( denotes the symmetric product).
Properties
The Kulkarni–Nomizu product of a pair of symmetric tensors has the algebraic symmetries of the Riemann tensor. For instance, on space forms (i.e. spaces of constant sectional curvature) and two-dimensional smooth Riemannian manifolds, the Riemann curvature tensor has a simple expression in terms of the Kulkarni–Nomizu product of the metric with itself; namely, if we denote by
the -curvature tensor and by
the Riemann curvature tensor with , then
where is the scalar curvature and
is the Ricci tensor, which in components reads .
Expanding the Kulkarni–Nomizu product using the definition from above, one obtains
This is the same expression as stated in the article on the Riemann curvature tensor.
For this very reason, it is commonly used to express the contribution that the Ricci curvature (or rather, the Schouten tensor) and the Weyl tensor each makes to the curvature of a Riemannian manifold. This so-called Ricci decomposition is useful in differential geometry.
When there is a metric tensor g, the Kulkarni–Nomizu product of g with itself is the identity endomorphism of the space of 2-forms, Ω2(M), under the identification (using the metric) of the endomorphism ring End(Ω2(M)) with the tensor product Ω2(M) ⊗ Ω2(M).
A Riemannian manifold has constant sectional curvature k if and only
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https://en.wikipedia.org/wiki/Acta%20Zoologica%20Academiae%20Scientiarum%20Hungaricae
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Acta Zoologica Academiae Scientiarum Hungaricae is a peer-reviewed, open access scientific journal no-publication fee, publishing original research studies in the fields of animal taxonomy, systematics, biogeography, and ecology. It was established in 1954 under the title Acta Zoologica Hungarica (1984–1993).
It is indexed in the Journal Citation Reports. The journal is also indexed in BIOSIS, Biological Abstracts, Abstracts of Entomology, CAB Abstracts, Forest Science Database, Current Contents, Human Genome Abstracts, Science Citation Index, and The Zoological Record.
See also
Open access in Hungary
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https://en.wikipedia.org/wiki/Structuralism%20%28philosophy%20of%20mathematics%29
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Structuralism is a theory in the philosophy of mathematics that holds that mathematical theories describe structures of mathematical objects. Mathematical objects are exhaustively defined by their place in such structures. Consequently, structuralism maintains that mathematical objects do not possess any intrinsic properties but are defined by their external relations in a system. For instance, structuralism holds that the number 1 is exhaustively defined by being the successor of 0 in the structure of the theory of natural numbers. By generalization of this example, any natural number is defined by its respective place in that theory. Other examples of mathematical objects might include lines and planes in geometry, or elements and operations in abstract algebra.
Structuralism is an epistemologically realistic view in that it holds that mathematical statements have an objective truth value. However, its central claim only relates to what kind of entity a mathematical object is, not to what kind of existence mathematical objects or structures have (not, in other words, to their ontology). The kind of existence that mathematical objects have would be dependent on that of the structures in which they are embedded; different sub-varieties of structuralism make different ontological claims in this regard.
Structuralism in the philosophy of mathematics is particularly associated with Paul Benacerraf, Geoffrey Hellman, Michael Resnik, Stewart Shapiro and James Franklin.
Historical motivation
The historical motivation for the development of structuralism derives from a fundamental problem of ontology. Since Medieval times, philosophers have argued as to whether the ontology of mathematics contains abstract objects. In the philosophy of mathematics, an abstract object is traditionally defined as an entity that: (1) exists independent of the mind; (2) exists independent of the empirical world; and (3) has eternal, unchangeable properties. Traditional mathematical Pla
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https://en.wikipedia.org/wiki/Wolf%20Barth
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Wolf Paul Barth (20 October 1942, Wernigerode – 30 December 2016, Nuremberg) was a German mathematician who discovered Barth surfaces and whose work on vector bundles has been important for the ADHM construction. Until 2011 Barth was working in the Department of Mathematics at the University of Erlangen-Nuremberg in Germany.
Barth received a PhD degree in 1967 from the University of Göttingen. His dissertation, written under the direction of Reinhold Remmert
and Hans Grauert, was entitled Einige Eigenschaften analytischer Mengen in kompakten komplexen Mannigfaltigkeiten (Some properties of analytic sets in compact, complex manifolds).
Publications
See also
Barth surfaces
Barth–Nieto quintic
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https://en.wikipedia.org/wiki/George%20Charles%20Beckley
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George Charles Beckley (March 5, 1787 – April 16, 1826) was an English captain, trader, and military adviser. He was one of the earliest foreigners to have a major impact in the Kingdom of Hawaii, where he eventually became a noble, and was one of the disputed creators of the Flag of Hawaii.
Life
Beckley was born in England, possibly on March 5, 1787. He moved to Veracruz when his father was granted a privateering licence by the Mexican government.
In 1801, Beckley arrived in Honolulu, in what was then known to him as the Sandwich Islands. He sold his ship to local chiefs and took up residence in the kingdom. During his early years in the islands, Beckley acted as a privateer; he waylaid ships on the high seas and sold many of them to King Kamehameha I, who was attempting to consolidate his control over the kingdom. The Englishman eventually rose to some prominence in the court of Kamehameha, and Beckley became one of the king’s foreign advisors. On the occasion of the birth of the Princess Nāhiʻenaʻena at Keauhou, Kona, Hawaii, in 1815, Beckley was made a high chief by Kamehameha I so that he might, with "impunity enter the sacred precincts of the grass house". Beckley "present[ed] the royal infant with a roll of China silk, after which he went outside and fired a salute of thirteen guns in her honor.".
American missionary Hiram Bingham I mentioned in his diary that an "Englishman Beckley" occupied a position of some importance on the islands. Russian explorer Otto von Kotzebue recorded his meeting with Beckley on the island of Oahu in his journal. Beckley continued to go to sea often, and was a major participator in the Sino-Hawaiian sandalwood trade. He organized trips to Fanning Island to hunt the valuable Hawaiian monk seal, and on occasion returned to privateering.
In 1816, Beckley became the first commander of Honolulu Fort, a military garrison erected on the waterfront of Honolulu by King Kamehameha I and Prime Minister Kalanimoku. The garrison was erec
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https://en.wikipedia.org/wiki/National%20research%20and%20education%20network
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A national research and education network (NREN) is a specialised internet service provider dedicated to supporting the needs of the research and education communities within a country.
It is usually distinguished by support for a high-speed backbone network, often offering dedicated channels for individual research projects.
In recent years NRENs have developed many 'above the net' services.
List of NRENs by geographic area
East and Southern Africa
UbuntuNet Alliance for Research and Education Networking - the Alliance of NRENs of East and Southern Africa
Eb@le - DRC NREN
EthERNet - Ethiopian NREN
iRENALA - Malagasy NREN
KENET - Kenyan NREN
MAREN - Malawian NREN
MoRENet - Mozambican NREN
RENU - Ugandan NREN
RwEdNet - Rwanda NREN
SomaliREN - Somali NREN
SudREN - Sudanese NREN
TENET/SANReN - South African NREN
TERNET - Tanzanian NREN
Xnet - Namibian NREN
ZAMREN - Zambian NREN
North Africa
ASREN - Arab States Research and Education Network
TUREN - Tunisian NREN
MARWAN - Moroccan NREN
ENREN - Egyptian NREN
ARN (Algeria) - Algerian NREN
SudREN - Sudanese NREN
SomaliREN - Somali NREN
West and Central Africa
WACREN - West and Central African Research and Education Network
GARNET - Ghanaian NREN
TogoRER - Togolese NREN
GhREN - Ghanaian NREN
MaliREN - Mali NREN
Niger-REN - Nigerien NREN
RITER - Côte d'Ivoire NREN
SnRER - Senegalese NREN
NgREN - Nigerian NREN
Eko-Konnect Research and Education Network - Nigerian NREN
LRREN - Liberia Research and Education Network
Asia Pacific
APAN - Asia-Pacific Advanced Network
AARNet - Australian NREN
AfgREN - Afghanistan NREN
BDREN - Bangladeshi NREN
CSTNET - China Science and Technology Network
CERNET - China Education and Research Network
ERNET - Indian NREN
HARNET - Hong Kong NREN
KOREN - Korean NREN
KREONET- Korean NREN
IDREN - Indonesian NREN
LEARN - Sri Lankan NREN
SINET - Japanese NREN
MYREN - Malaysian NREN
NKN - Indian NREN
NREN - Nepal NREN
NREN - Islamic Republic of Iran N
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