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https://en.wikipedia.org/wiki/Microbial%20metabolism
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Microbial metabolism is the means by which a microbe obtains the energy and nutrients (e.g. carbon) it needs to live and reproduce. Microbes use many different types of metabolic strategies and species can often be differentiated from each other based on metabolic characteristics. The specific metabolic properties of a microbe are the major factors in determining that microbe's ecological niche, and often allow for that microbe to be useful in industrial processes or responsible for biogeochemical cycles.
Types
All microbial metabolisms can be arranged according to three principles:
1. How the organism obtains carbon for synthesizing cell mass:
autotrophic – carbon is obtained from carbon dioxide ()
heterotrophic – carbon is obtained from organic compounds
mixotrophic – carbon is obtained from both organic compounds and by fixing carbon dioxide
2. How the organism obtains reducing equivalents (hydrogen atoms or electrons) used either in energy conservation or in biosynthetic reactions:
lithotrophic – reducing equivalents are obtained from inorganic compounds
organotrophic – reducing equivalents are obtained from organic compounds
3. How the organism obtains energy for living and growing:
phototrophic – energy is obtained from light
chemotrophic – energy is obtained from external chemical compounds
In practice, these terms are almost freely combined. Typical examples are as follows:
chemolithoautotrophs obtain energy from the oxidation of inorganic compounds and carbon from the fixation of carbon dioxide. Examples: Nitrifying bacteria, sulfur-oxidizing bacteria, iron-oxidizing bacteria, Knallgas-bacteria
photolithoautotrophs obtain energy from light and carbon from the fixation of carbon dioxide, using reducing equivalents from inorganic compounds. Examples: Cyanobacteria (water () as reducing equivalent = hydrogen donor), Chlorobiaceae, Chromatiaceae (hydrogen sulfide () as hydrogen donor), Chloroflexus (hydrogen () as reducing equivalent donor)
che
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https://en.wikipedia.org/wiki/Lateral%20nasal%20cartilage
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The lateral cartilage (upper lateral cartilage, lateral process of septal nasal cartilage) is situated below the inferior margin of the nasal bone, and is flattened, and triangular in shape.
Its anterior margin is thicker than the posterior, and is continuous above with the septal nasal cartilage, but separated from it below by a narrow fissure; its superior margin is attached to the nasal bone and the frontal process of the maxilla; its inferior margin is connected by fibrous tissue with the greater alar cartilage. Where the lateral cartilage meets the greater alar cartilage, the lateral cartilage often curls up, to join with an inward curl of the greater alar cartilage. That curl of the inferior portion of the lateral cartilage is called its "scroll."
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https://en.wikipedia.org/wiki/Central%20Board%20of%20Film%20Certification
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The Central Board of Film Certification (CBFC) is a statutory film-certification body in the Ministry of Information and Broadcasting of the Government of India. It is tasked with "regulating the public exhibition of films under the provisions of the Cinematograph Act 1952." The Cinematograph Act 1952 outlines a strict certification process for commercial films shown in public venues. Films screened in cinemas and on television may only be publicly exhibited in India after certification by the board and edited.
Certificates and guidelines
The board currently issues four certificates. Originally, there were two: U (unrestricted public exhibition with family-friendly movies) and A (restricted to adult audiences but any kind of nudity not allowed). Two more were added in June U/A (unrestricted public exhibition, with parental guidance for children under 12) and S (restricted to specialised audiences, such as doctors or scientists). The board may refuse to certify a film. Additionally, V/U, V/UA, V/A are used for video releases with U, U/A and A carrying the same meaning as above.
U certificate
Films with the U certification are fit for unrestricted public exhibition and are family-friendly. These films can contain universal themes like education, family, drama, romance, sci-fi, action etc. These films can also contain some mild violence, but it cannot be prolonged. It may also contain very mild sexual scenes (without any traces of nudity or sexual detail).
U/A certificate
Films with the U/A certification can contain moderate adult themes that are not strong in nature and are not considered appropriate to be watched by a child below 12 years of age with parental guidance. These films may contain moderate to strong violence, moderate sexual scenes (traces of nudity and moderate sexual detail can be found), frightening scenes, blood flow, or muted abusive language. Sometimes such films are re-certified with V/U for video viewing.
A certificate
Films with the A ce
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https://en.wikipedia.org/wiki/KronoScope
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KronoScope. Journal for the Study of Time is a peer-reviewed academic journal dedicated to the interdisciplinary study of time, both in the humanities and in the sciences. It is published biannually under the imprint of Brill Publishers on behalf of the International Society for the Study of Time. It is indexed in Sociological Abstracts.
See also
Julius Thomas Fraser
Temporality
Time
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https://en.wikipedia.org/wiki/Hailey%E2%80%93Hailey%20disease
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Hailey–Hailey disease (HHD), or familial benign chronic pemphigus or familial benign pemphigus, was originally described by the Hailey brothers (Hugh Edward and William Howard) in 1939. It is a genetic disorder that causes blisters to form on the skin.
Signs and symptoms
HHD is characterized by outbreaks of rashes and blisters on the skin. Affected areas of skin undergo repeated blistering and inflammation, and may be painful to the touch. Areas where the skin folds, as well as the armpits, groin, neck, buttocks and under the breasts are most commonly affected. In addition to blistering, other symptoms which accompany HHD include acantholysis, erythema and hyperkeratosis.
Causes
The cause of the disease is a haploinsufficiency of the enzyme ATP2C1; the ATP2C1 gene is located on chromosome 3, which encodes the protein hSPCA1. A mutation on one copy of the gene causes only half of this necessary protein to be made and the cells of the skin do not adhere together properly due to malformation of intercellular desmosomes, causing acantholysis, blisters and rashes. There is no known cure.
Diagnosis
Classification
While the term pemphigus typically refers to "a rare group of blistering autoimmune diseases" affecting "the skin and mucous membranes", Hailey–Hailey disease is not an autoimmune disorder and there are no autoantibodies. According to Pemphigus Pemphigoid Foundation (IPPF), "familial benign chronic pemphigus, or Hailey-Hailey disease, is a different condition from Pemphigus".
Differential diagnosis
The differential diagnosis includes intertrigo, candidiasis, frictional or contact dermatitis, and inverse psoriasis. A biopsy and/or family history can confirm. The lack of oral lesions and intercellular antibodies distinguishes familial benign pemphigus from other forms of pemphigus.
Treatment
Topical steroid preparations often help outbreaks; use of the weakest corticosteroid that is effective is recommended to help prevent thinning of the skin. Drugs such
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https://en.wikipedia.org/wiki/Sexual%20mimicry
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Sexual mimicry occurs when one sex mimics the opposite sex in its behavior, appearance, or chemical signalling.
It is more commonly seen within invertebrate species, although sexual mimicry is also seen among vertebrates such as spotted hyenas.
Sexual mimicry is commonly used as a mating strategy to gain access to a mate, a defense mechanism to avoid more dominant individuals, or a survival strategy. It can also be a physical characteristic that establishes an individual's place in society. Sexual mimicry is employed differently across species and it is part of their strategy for survival and reproduction.
Examples of intraspecific sexual mimicry in animals include the spotted hyena, certain types of fish, passerine birds and some species of insect.
Interspecific sexual mimicry can also occur in some plant species, especially orchids. In plants employing sexual mimicry, flowers mimic mating signals of their pollinator insects. These insects are attracted and pollinate the flowers through pseudocopulations or other sexual behaviors performed on the flower.
Social systems
Sexual mimicry can play a role in the development of a species' social system. Perhaps the most extreme example of this can be seen in the spotted hyena, Crocuta crocuta. Female hyenas of all ages possess pseudomasculinized genitalia, including a pseudopenis formed from the clitoris, and a false scrotum formed from the labia. These characteristics likely initially evolved to reduce rates of intrasex aggression received by cub and juvenile females from adult females. However, the trait has evolved beyond its initial use to become highly relevant to spotted hyena communication. Subordinate hyenas will greet dominant individuals by erecting their penis or pseudopenis and allowing the dominant individual to lick it. This likely initially evolved as a means of discerning the sex of the subordinate individual, as the pseudopenis less closely resembles a genuine penis when erect, and tasting the a
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https://en.wikipedia.org/wiki/Fairy%20riding
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Fairy riding (Scottish Gaelic: marcachd shìth/a' mharcachd-shìth/na marcachd-shìth) was a term used for a kind of paralysis found in livestock in Scotland. It occurred in the spine of sheep, cows and horses, and was attributed to fairies riding on them.
It was also attributed in some places where perspiration, due to weakness, was discovered in cattle.
It can be compared to elf-shot, where fairies were thought to have shot animals.
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https://en.wikipedia.org/wiki/Minifloat
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In computing, minifloats are floating-point values represented with very few bits. Predictably, they are not well suited for general-purpose numerical calculations. They are used for special purposes, most often in computer graphics, where iterations are small and precision has aesthetic effects. Machine learning also uses similar formats like bfloat16. Additionally, they are frequently encountered as a pedagogical tool in computer-science courses to demonstrate the properties and structures of floating-point arithmetic and IEEE 754 numbers.
Minifloats with 16 bits are half-precision numbers (opposed to single and double precision). There are also minifloats with 8 bits or even fewer.
Minifloats can be designed following the principles of the IEEE 754 standard. In this case they must obey the (not explicitly written) rules for the frontier between subnormal and normal numbers and must have special patterns for infinity and NaN. Normalized numbers are stored with a biased exponent. The new revision of the standard, IEEE 754-2008, has 16-bit binary minifloats.
Notation
A minifloat is usually described using a tuple of four numbers, (S, E, M, B):
S is the length of the sign field. It is usually either 0 or 1.
E is the length of the exponent field.
M is the length of the mantissa (significand) field.
B is the exponent bias.
A minifloat format denoted by (S, E, M, B) is, therefore, bits long.
In computer graphics minifloats are sometimes used to represent only integral values. If at the same time subnormal values should exist, the least subnormal number has to be 1. The bias value would be in this case, assuming two special exponent values are used per IEEE.
The (S, E, M, B) notation can be converted to a (B, P, L, U) format as (with IEEE use of exponents).
Example 8-bit float
A minifloat in 1 byte (8 bit) with 1 sign bit, 4 exponent bits and 3 significand bits (in short, a 1.4.3 minifloat) is demonstrated here. The exponent bias is defined as 7 to cente
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https://en.wikipedia.org/wiki/Georg%20Nees
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Georg Nees (23 June 1926 – 3 January 2016) was a German academic who was a pioneer of computer art and generative graphics. He studied mathematics, physics and philosophy in Erlangen and Stuttgart and was scientific advisor at the SEMIOSIS, International Journal of semiotics and aesthetics. In 1977, he was appointed Honorary Professor of Applied computer science at the University of Erlangen Nees is one of the "3N" computer pioneers, an abbreviation that has become acknowledged for Frieder Nake, Georg Nees and A. Michael Noll, whose computer graphics were created with digital computers.
Early life and studies
Georg Nees was born in 1926 in Nuremberg, where he spent his childhood. He showed scientific curiosity and interest in art from a young age and among his favorite pastimes were viewing art postcards and looking through a microscope. He attended a school in Schwabach near Nuremberg, graduating in 1945. From 1945 to 1951, he studied mathematics and physics at the University of Erlangen then worked as an industry mathematician for the Siemens Schuckertwerk in Erlangen from 1951 to 1985. There he started to write his first programs in 1959. The company was later incorporated into the Siemens AG.
From 1964 onwards, he studied philosophy at the Technische Hochschule Stuttgart (since 1967 the University of Stuttgart), under Max Bense. He received his doctorate with his thesis on Generative Computergraphik under Max Bense in 1969. His work is considered one of the first theses on Generative Computer Graphics. In 1969, his thesis was published as a book entitled "Generative Computergraphik" and also included examples of program code and graphics produced thereby. After his retirement in 1985 Nees worked as an author and in the field of computer art.
Computer art
In February 1965, Nees showed - as works of art - the world's first computer graphics created with a digital computer. The exhibition, titled computer graphik took place at the public premises of the "Stud
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https://en.wikipedia.org/wiki/Intervertebral%20foramen
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The intervertebral foramen (also neural foramen) (often abbreviated as IV foramen or IVF) is an opening between (the intervertebral notches of) two pedicles (one above and one below) of adjacent vertebra in the articulated spine. Each intervertebral foramen gives passage to a spinal nerve and spinal blood vessels, and lodges a posterior (dorsal) root ganglion. Cervical, thoracic, and lumbar vertebrae all have intervertebral foramina.
Anatomy
Structure
In the thoracic region and lumbar region, each vertebral foramen is additionally bounded anteriorly by (the inferior portion of) the body of vertebra (particularly in the thoracic region) and adjacent intervertebral disc (particularly in the lumbar region).
In the cervical region, a small part of the body of vertebra inferior to the intervertebral disc also forms the anterior boundary of the IVF (due to the fact that the junction of the pedicle with the body of vertebra is situated somewhat more inferiorly on the body).
Contents
A number of structures pass through the IVF: spinal nerve roots, a recurrent meningeal nerve, radicular arteries (where present), segmental medullary arteries (where present), intervertebral veins, and lymphatic vessels.
The posterior (dorsal) root ganglion is situated within the IVF. The adipose tissue of the spinal epidural space extends into the IVF. The spinal dura mater extends laterally with each departing spinal nerve, reaching into the IVF. Transforaminal ligaments (when present) extend through the IFV.
Clinical significance
Foramina can be occluded by arthritic degenerative changes and space-occupying lesions like tumors, metastases, and spinal disc herniations.
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https://en.wikipedia.org/wiki/Sister%20chromatid%20exchange
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Sister chromatid exchange (SCE) is the exchange of genetic material between two identical sister chromatids.
It was first discovered by using the Giemsa staining method on one chromatid belonging to the sister chromatid complex before anaphase in mitosis. The staining revealed that few segments were passed to the sister chromatid which were not dyed.
The Giemsa staining was able to stain due to the presence of bromodeoxyuridine analogous base which was introduced to the desired chromatid.
The reason for the (SCE) is not known but it is required and used as a mutagenic testing of many products. Four to five sister chromatid exchanges per chromosome pair, per mitosis is in the normal distribution, while 14–100 exchanges is not normal and presents a danger to the organism. SCE is elevated in pathologies including Bloom syndrome, having recombination rates ~10–100 times above normal, depending on cell type. Frequent SCEs may also be related to formation of tumors.
Sister chromatid exchange has also been observed more frequently in B51(+) Behçet's disease.
Mitosis
Mitotic recombination in the budding yeast Saccharomyces cerevisiae is primarily a result of DNA repair processes responding to spontaneous or induced damages that occur during vegetative growth.} (Also reviewed in Bernstein and Bernstein, pp 220–221). In order for yeast cells to repair damage by homologous recombination, there must be present, in the same nucleus, a second DNA molecule containing sequence homology with the region to be repaired. In a diploid cell in G1 phase of the cell cycle, such a molecule is present in the form of the homologous chromosome. However, in the G2 phase of the cell cycle (following DNA replication), a second homologous DNA molecule is also present: the sister chromatid. Evidence indicates that, due to the special nearby relationship they share, sister chromatids are not only preferred over distant homologous chromatids as substrates for recombinational repair, but have
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https://en.wikipedia.org/wiki/Marginal%20mandibular%20branch%20of%20the%20facial%20nerve
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The marginal mandibular branch of the facial nerve arises from the facial nerve (CN VII) in the parotid gland at the parotid plexus. It passes anterior-ward deep to the platysma and depressor anguli oris muscles. It provides motor innervation to muscles of the lower lip and chin: the depressor labii inferioris muscle, depressor anguli oris muscle, and mentalis muscle. It communicates with the mental branch of the inferior alveolar nerve.
Clinical significance
Iatrogenic damage
The marginal mandibular nerve may be injured during surgery in the neck region, especially during excision of the submandibular salivary gland or during neck dissections due to lack of accurate knowledge of variations in the course, branches and relations. An injury to this nerve during a surgical procedure can distort the expression of the smile as well as other facial expressions. The marginal mandibular branch of the facial nerve is found superficial to the facial artery and (anterior) facial vein. Thus the facial artery can be used as an important landmark in locating the marginal mandibular nerve during surgical procedures. Damage can cause paralysis of the three muscles it supplies, which can cause an asymmetrical smile due to lack of contraction of the depressor labii inferioris muscle. This may be corrected with resection of the muscle, which tends to be successful.
Additional images
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https://en.wikipedia.org/wiki/Buccal%20branches%20of%20the%20facial%20nerve
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The buccal branches of the facial nerve (infraorbital branches), are of larger size than the rest of the branches, pass horizontally forward to be distributed below the orbit and around the mouth.
Branches
The superficial branches run beneath the skin and above the superficial muscles of the face, which they supply: some are distributed to the procerus, joining at the medial angle of the orbit with the infratrochlear and nasociliary branches of the ophthalmic.
The deep branches pass beneath the zygomaticus and the quadratus labii superioris, supplying them and forming an infraorbital plexus with the infraorbital branch of the maxillary nerve. These branches also supply the small muscles of the nose.
The lower deep branches supply the buccinator and orbicularis oris, and join with filaments of the buccinator branch of the mandibular nerve.
Muscles of facial expression
The facial nerve innervates the muscles of facial expression. The buccal branch supplies these muscles
Testing the nerve
• Puff up cheeks (buccinator)
i. Tap with finger over each cheek to detect ease of air expulsion on the affected side
• Smile and show teeth (orbicularis oris)
See also
Buccal nerve
Additional images
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https://en.wikipedia.org/wiki/Posterior%20auricular%20nerve
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The posterior auricular nerve is a nerve of the head. It is a branch of the facial nerve (CN VII). It communicates with branches from the vagus nerve, the great auricular nerve, and the lesser occipital nerve. Its auricular branch supplies the posterior auricular muscle, the intrinsic muscles of the auricle, and gives sensation to the auricle. Its occipital branch supplies the occipitalis muscle.
Structure
The posterior auricular nerve arises from the facial nerve (CN VII). It is the first branch outside of the skull. This origin is close to the stylomastoid foramen. It runs upward in front of the mastoid process. It is joined by a branch from the auricular branch of the vagus nerve (CN X). It communicates with the posterior branch of the great auricular nerve, as well as with the lesser occipital nerve.
As it ascends between the external acoustic meatus and mastoid process it divides into auricular and occipital branches.
The auricular branch travels to the posterior auricular muscle and the intrinsic muscles on the cranial surface of the auricule.
The occipital branch, the larger branch, passes backward along the superior nuchal line of the occipital bone to the occipitalis muscle.
Function
The posterior auricular nerve supplies the posterior auricular muscle, and the intrinsic muscles of the auricle. It gives sensation to the auricle. It also supplies the occipitalis muscle.
Clinical significance
Nerve testing
The posterior auricular nerve can be tested by contraction of the occipitalis muscle, and by sensation in the auricle. This testing is rarely performed.
Biopsy
The posterior auricular nerve can be biopsied. This can be used to test for leprosy, which can be important in diagnosis.
See also
posterior auricular artery
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https://en.wikipedia.org/wiki/Dinocyst
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Dinocysts or dinoflagellate cysts are typically 15 to 100 µm in diameter and produced by around 15–20% of living dinoflagellates as a dormant, zygotic stage of their lifecycle, which can accumulate in the sediments as microfossils. Organic-walled dinocysts are often resistant and made out of dinosporin. There are also calcareous dinoflagellate cysts and siliceous dinoflagellate cysts.
History
The first person to recognize fossil dinoflagellates was Christian Gottfried Ehrenberg, who reported his discovery in a paper presented to the Berlin Academy of Sciences in July 1836. He had observed clearly tabulate dinoflagellates in thin flakes of Cretaceous flint and considered those dinoflagellates to have been silicified. Along with them, and of comparable size, were spheroidal to ovoidal bodies bearing an array of spines or tubes of variable character. Ehrenberg interpreted these as being originally siliceous and thought them to be desmids (freshwater conjugating algae), placing them within his own Recent desmid genus Xanthidium. Though summaries of Ehrenberg's work appeared earlier, it was not published in full until 1837 or 1838; the date is uncertain.
A first relation between dinoflagellate thecae and cysts was made through morphological comparison of both by Bill Evitt and Susan E. Davidson. Further evidence came from detailed culture studies of dinoflagellate cysts by David Wall and Barrie Dale at Woods Hole Oceanographic Institution in the sixties.
Types of cysts
Ontologically, the term cyst can apply to (1) a temporary resting state (pellicle, temporary or ecdysal cyst), (2) a dormant zygote (resting cysts or hypnozygotes) or (3) a coccoid condition in which the cells are still photosynthetically active. For example, for this last special case, all cysts described from species of the order Phytodiniales (e.g. Cystodinium, Stylodinium, Hypnodinium, Tetradinium, Dinococcus, Gloeodinium), are coccoid stages.
Digestive cyst or digestion cysts denote pellicle c
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https://en.wikipedia.org/wiki/FSU%20Young%20Scholars%20Program
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FSU Young Scholars Program (YSP) is a six-week residential science and mathematics summer program for 40 high school students from Florida, USA, with significant potential for careers in the fields of science, technology, engineering and mathematics. The program was developed in 1983 and is currently administered by the Office of Science Teaching Activities in the College of Arts and Sciences at Florida State University (FSU).
Academic program
Each young scholar attends three courses in the fields of mathematics, science and computer programming. The courses are designed specifically for this program — they are neither high school nor college courses.
Research
Each student who attends YSP is assigned an independent research project (IRP) based on his or her interests. Students join the research teams of FSU professors, participating in scientific research for two days each week. The fields of study available include robotics, molecular biology, chemistry, geology, physics and zoology. At the conclusion of the program, students present their projects in an academic conference, documenting their findings and explaining their projects to both students and faculty.
Selection process
YSP admits students who have completed the eleventh grade in a Florida public or private high school. A few exceptionally qualified and mature tenth graders have been selected in past years, though this is quite rare.
All applicants must have completed pre-calculus and maintain at least a 3.0 unweighted GPA to be considered for acceptance. Additionally, students must have scored at the 90th percentile or better in science or mathematics on a nationally standardized exam, such as the SAT, PSAT, ACT or PLAN. Students are required to submit an application package, including high school transcripts and a letter of recommendation.
Selection is extremely competitive, as there are typically over 200 highly qualified applicants competing for only 40 positions. The majority of past participant
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https://en.wikipedia.org/wiki/Gradient%20theorem
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The gradient theorem, also known as the fundamental theorem of calculus for line integrals, says that a line integral through a gradient field can be evaluated by evaluating the original scalar field at the endpoints of the curve. The theorem is a generalization of the second fundamental theorem of calculus to any curve in a plane or space (generally n-dimensional) rather than just the real line.
For as a differentiable function and as any continuous curve in which starts at a point and ends at a point , then
where denotes the gradient vector field of .
The gradient theorem implies that line integrals through gradient fields are path-independent. In physics this theorem is one of the ways of defining a conservative force. By placing as potential, is a conservative field. Work done by conservative forces does not depend on the path followed by the object, but only the end points, as the above equation shows.
The gradient theorem also has an interesting converse: any path-independent vector field can be expressed as the gradient of a scalar field. Just like the gradient theorem itself, this converse has many striking consequences and applications in both pure and applied mathematics.
Proof
If is a differentiable function from some open subset to and is a differentiable function from some closed interval to (Note that is differentiable at the interval endpoints and . To do this, is defined on an interval that is larger than and includes .), then by the multivariate chain rule, the composite function is differentiable on :
for all in . Here the denotes the usual inner product.
Now suppose the domain of contains the differentiable curve with endpoints and . (This is oriented in the direction from to ). If parametrizes for in (i.e., represents as a function of ), then
where the definition of a line integral is used in the first equality, the above equation is used in the second equality, and the second fundamental theorem of calculus
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https://en.wikipedia.org/wiki/Medial%20supracondylar%20ridge
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The inferior third of the medial border of the humerus is raised into a slight ridge, the medial supracondylar ridge (or medial supracondylar line), which becomes very prominent below; it presents an anterior lip for the origins of the Brachialis and Pronator teres, a posterior lip for the medial head of the Triceps brachii, and an intermediate ridge for the attachment of the medial intermuscular septum.
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https://en.wikipedia.org/wiki/Medial%20epicondyle%20of%20the%20humerus
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The medial epicondyle of the humerus is an epicondyle of the humerus bone of the upper arm in humans. It is larger and more prominent than the lateral epicondyle and is directed slightly more posteriorly in the anatomical position. In birds, where the arm is somewhat rotated compared to other tetrapods, it is called the ventral epicondyle of the humerus. In comparative anatomy, the more neutral term entepicondyle is used.
The medial epicondyle gives attachment to the ulnar collateral ligament of elbow joint, to the pronator teres, and to a common tendon of origin (the common flexor tendon) of some of the flexor muscles of the forearm: the flexor carpi radialis, the flexor carpi ulnaris, the flexor digitorum superficialis, and the palmaris longus. The medial epicondyle is located on the distal end of the humerus. Additionally, the medial epicondyle is inferior to the medial supracondylar ridge. It is also proximal to the olecranon fossa.
The medial epicondyle protects the ulnar nerve, which runs in a groove on the back of this epicondyle. The ulnar nerve is vulnerable because it passes close to the surface along the back of the bone. Striking the medial epicondyle causes a tingling sensation in the ulnar nerve. This response is known as striking the "funny bone". The name funny bone could be from a play on the words humorous and humerus, the bone on which the medial epicondyle is located, although according to the Oxford English Dictionary, it may refer to "the peculiar sensation experienced when it is struck". Medial epicondyle fracture of the humerus are common when falling onto an outstretched hand.
Fractures
Medial epicondyle fractures are common elbow injuries in children. There is considerable controversy about their treatment, with uncertainty about whether surgery to restore the natural position of the bone is better than healing in a cast.
Additional images
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https://en.wikipedia.org/wiki/Cult%20wine
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Cult wines are wines for which dedicated groups of committed enthusiasts will pay large sums of money.
Cult wines are often seen as trophy wines to be collected or as investment wine to be held rather than consumed. Because price is often seen as an indicator of quality, sellers may adopt a premium pricing strategy where high prices are used to increase the desirability of such wines. This is true even for less expensive wines. For example, one vintner explained that "on several occasions we have had difficulty selling wines at US$75, but as soon as we raise the price to US$125 they sell out and get put on allocation".
Other wines that fall under the title occasionally are from Burgundy, Bordeaux, Rhône and Italy.
These wines when scored highly by Robert Parker have had a tendency to increase in price resembling the Bordeaux investment market.
California cult wines
California cult wines refers to any of the California wines "typically but not exclusively Napa Valley Cabernets" for which collectors, investors and enthusiastic consumers will pay high prices. The emergence of the cult movement coincided with trends in the 1990s towards riper fruit and wines with bigger and more concentrated flavors.
These wines are generally very expensive, have limited production (often fewer than 600 cases per year) and can sell for several times their "release price" in the secondary market.
Bordeaux cult wines
The cult wines of Bordeaux tend to be left-bank cabernet-based wines that ranked highly in the Classification of 1855.
See also
Conspicuous consumption
Cult following
Langton’s Classification of Australian Wine
Luxury good
Garagistes
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https://en.wikipedia.org/wiki/Medial%20epicondyle%20of%20the%20femur
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The medial epicondyle of the femur is an epicondyle, a bony protrusion, located on the medial side of the femur at its distal end.
Located above the medial condyle, it bears an elevation, the adductor tubercle, which serves for the attachment of the superficial part, or "tendinous insertion", of the adductor magnus. This tendinous part here forms an intermuscular septum which forms the medial separation between the thigh's flexors and extensors.<ref name="Platzer-242
The anterior long fibers of the tibial collateral ligament of the knee-joint are attached to it.
Behind it, and proximal to the medial condyle is a rough impression which gives origin to the medial head of the Gastrocnemius.
See also
Lateral epicondyle of the femur
Medial epicondyle of the humerus
Notes
Additional images
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https://en.wikipedia.org/wiki/Lateral%20epicondyle%20of%20the%20femur
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The lateral epicondyle of the femur, smaller and less prominent than the medial epicondyle, gives attachment to the fibular collateral ligament of the knee-joint. Directly below it is a small depression from which a smooth well-marked groove curves obliquely upward and backward to the posterior extremity of the condyle.
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https://en.wikipedia.org/wiki/Respirometry
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Respirometry is a general term that encompasses a number of techniques for obtaining estimates of the rates of metabolism of vertebrates, invertebrates, plants, tissues, cells, or microorganisms via an indirect measure of heat production (calorimetry).
Whole-animal metabolic rates
The metabolism of an animal is estimated by determining rates of carbon dioxide production (VCO2) and oxygen consumption (VO2) of individual animals, either in a closed or an open-circuit respirometry system. Two measures are typically obtained: standard (SMR) or basal metabolic rate (BMR) and maximal rate (VO2max). SMR is measured while the animal is at rest (but not asleep) under specific laboratory (temperature, hydration) and subject-specific conditions (e.g., size or allometry), age, reproduction status, post-absorptive to avoid thermic effect of food). VO2max is typically determined during aerobic exercise at or near physiological limits. In contrast, field metabolic rate (FMR) refers to the metabolic rate of an unrestrained, active animal in nature. Whole-animal metabolic rates refer to these measures without correction for body mass. If SMR or BMR values are divided by the body mass value for the animal, then the rate is termed mass-specific. It is this mass-specific value that one typically hears in comparisons among species.
Closed respirometry
Respirometry depends on a "what goes in must come out" principle. Consider a closed system first. Imagine that we place a mouse into an air-tight container. The air sealed in the container initially contains the same composition and proportions of gases that were present in the room: 20.95% O2, 0.04% CO2, water vapor (the exact amount depends on air temperature, see dew point), 78% (approximately) N2, 0.93% argon and a variety of trace gases making up the rest (see Earth's atmosphere). As time passes, the mouse in the chamber produces CO2 and water vapor, but extracts O2 from the air in proportion to its metabolic demands. Therefo
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https://en.wikipedia.org/wiki/Geobotanical%20prospecting
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Geobotanical prospecting refers to prospecting based on indicator plants like metallophytes and the analysis of vegetation. For example, the Viscaria Mine in Sweden was named after the plant Silene suecica (syn. Viscaria alpina) that was used by prospectors to discover the ore deposits.
A "most faithful" indicator plant is Ocimum centraliafricanum, the "copper plant" or "copper flower" formerly known as Becium homblei, found only on copper (and nickel) containing soils in central to southern Africa.
In 2015, Stephen E. Haggerty identified Pandanus candelabrum as a botanical indicator for kimberlite pipes, a source of mined diamonds.
The technique has been used in China since in the 5th century BC. People in the region noticed a connection between vegetation and the minerals located underground. There were particular plants that throve on and indicated areas rich in copper, nickel, zinc, and allegedly gold though the latter has not been confirmed. The connection arose out of an agricultural interest concerning soil compositions. While the process had been known to the Chinese region since antiquity, it was not written about and studied in the west until the 18th century in Italy.
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https://en.wikipedia.org/wiki/Lesser%20tubercle
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The lesser tubercle of the humerus, although smaller, is more prominent than the greater tubercle: it is situated in front, and is directed medially and anteriorly.
The projection of the lesser tubercle is anterior from the junction that is found between the anatomical neck and the shaft of the humerus and easily identified due to the intertubercular sulcus (Bicipital groove).
Above and in front it presents an impression for the insertion of the tendon of the subscapularis.
Additional images
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https://en.wikipedia.org/wiki/Greater%20tubercle
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The greater tubercle of the humerus is the outward part the upper end of that bone, adjacent to the large rounded prominence of the humerus head. It provides attachment points for the supraspinatus, infraspinatus, and teres minor muscles, three of the four muscles of the rotator cuff, a muscle group that stabilizes the shoulder joint. In doing so the tubercle acts as a location for the transfer of forces from the rotator cuff muscles to the humerus.
Structure
The upper surface of the greater tubercle is rounded, and marked by three flat impressions:
the highest ("superior facet") gives insertion to the supraspinatus muscle.
the middle ("middle facet") gives insertion to the infraspinatus muscle.
the lowest ("inferior facet"), and the body of the bone for about 2.5 cm, gives insertion to the teres minor muscle.
The lateral surface of the greater tubercle is convex, rough, and continuous with the lateral surface of the body of the humerus. It can be described as having a cranial and a caudal part.
Between the greater tubercle and the lesser tubercle is the bicipital groove (intertubercular sulcus).
Function
All three of the muscles that attach to the greater tubercle are part of the rotator cuff, a muscle group that stabilizes the shoulder joint. The greater tubercle therefore acts as a location for the transfer of forces from the rotator cuff muscles to the humerus.
The fourth muscle of the rotator cuff (subscapularis muscle) does not attach to the greater tubercle, but instead attaches to the lesser tubercle.
Clinical significance
The greater tubercle is usually the easiest part of the humerus to palpate. It can be a useful surface landmark during surgery.
Additional images
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https://en.wikipedia.org/wiki/Antebrachial%20fascia
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The antebrachial fascia (antibrachial fascia or deep fascia of forearm) continuous above with the brachial fascia, is a dense, membranous investment, which forms a general sheath for the muscles in this region; it is attached, behind, to the olecranon and dorsal border of the ulna, and gives off from its deep surface numerous intermuscular septa, which enclose each muscle separately.
Over the flexor muscles tendons as they approach the wrist it is especially thickened, and forms the volar carpal ligament.
This is continuous with the transverse carpal ligament, and forms a sheath for the tendon of the palmaris longus which passes over the transverse carpal ligament to be inserted into the palmar aponeurosis.
Behind, near the wrist-joint, it is thickened by the addition of many transverse fibers, and forms the dorsal carpal ligament.
It is much thicker on the dorsal than on the volar surface, and at the lower than at the upper part of the forearm, and is strengthened above by tendinous fibers derived from the Biceps brachii in front, and from the Triceps brachii behind.
It gives origin to muscular fibers, especially at the upper part of the medial and lateral sides of the forearm, and forms the boundaries of a series of cone-shaped cavities, in which the muscles are contained.
Besides the vertical septa separating the individual muscles, transverse septa are given off both on the volar and dorsal surfaces of the forearm, separating the deep from the superficial layers of muscles.
Apertures exist in the fascia for the passage of vessels and nerves; one of these apertures of large size, situated at the front of the elbow, serves for the passage of a communicating branch between the superficial and deep veins.
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https://en.wikipedia.org/wiki/Mikhail%20Suslin
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Mikhail Yakovlevich Suslin (; , November 15, 1894 – 21 October 1919, Krasavka) (sometimes transliterated Souslin) was a Russian mathematician who made major contributions to the fields of general topology and descriptive set theory.
Biography
Mikhail Suslin was born on November 15, 1894, in the village of Krasavka, the only child of poor peasants Yakov Gavrilovich and Matrena Vasil'evna Suslin. From a young age, Suslin showed a keen interest in mathematics and was encouraged to continue his education by his primary school teacher, Vera Andreevna Teplogorskaya-Smirnova. From 1905 to 1913 he attended Balashov boys' grammar school.
In 1913, Suslin enrolled at the Imperial Moscow University and studied under the tutelage of Nikolai Luzin. He graduated with a degree in mathematics in 1917 and immediately began working at the Ivanovo-Voznesensk Polytechnic Institute.
Suslin died of typhus in the 1919 Moscow epidemic following the Russian Civil War, at the age of 24.
Work
His name is especially associated to Suslin's problem, a question relating to totally ordered sets that was eventually found to be independent of the standard system of set-theoretic axioms, ZFC.
He contributed greatly to the theory of analytic sets, sometimes called after him, a kind of a set of reals that is definable via trees. In fact, while he was a research student of Nikolai Luzin (in 1917) he found an error in an argument of Lebesgue, who believed he had proved that for any Borel set in , the projection onto the real axis was also a Borel set.
Publications
Suslin only published one paper during his life: a 4-page note.
See also
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https://en.wikipedia.org/wiki/OPIE%20Authentication%20System
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OPIE is the initialism of "One time Passwords In Everything".
Opie is a mature, Unix-like login and password package
installed on the server and the client which makes untrusted networks safer against password-sniffing packet-analysis software like dSniff and safe against shoulder surfing.
It works by circumventing the delayed attack method because the same password is never used twice after installing Opie.
OPIE implements a one-time password (OTP) scheme based on S/KEY, which will require a secret passphrase (not echoed) to generate a password for the current session, or a list of passwords you can print and carry on your person.
OPIE uses an MD4 or MD5 hash function to generate passwords.
OPIE can restrict its logins based on IP address. It uses its own passwd and login modules.
If the Enter key is pressed at the password prompt, it will turn echo on, so what is being typed can be seen when entering an unfamiliar password from a printout.
OPIE can improve security when accessing online banking at conferences, hotels and airports. Some countries require banks to implement OTP.
OPIE shipped with DragonFly BSD, FreeBSD and OpenSUSE. It can be installed on a Unix-like server and clients for improved security.
The commands are
opiepasswd
opiekey
See also
OTPW
External links
OPIE @ Linux wiki
Opie text from FreeBSD Manual
Cryptographic software | Password authentication
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https://en.wikipedia.org/wiki/Royal%20cypher
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In modern heraldry, a royal cypher is a monogram or monogram-like device of a country's reigning sovereign, typically consisting of the initials of the monarch's name and title, sometimes interwoven and often surmounted by a crown. Such a cypher as used by an emperor or empress is called an imperial cypher. In the system used by various Commonwealth realms, the title is abbreviated as 'R' for or (Latin for "king" and "queen"). Previously, 'I' stood for or (Latin for "emperor" and "empress") of the Indian Empire.
Royal cyphers appear on some government buildings, impressed upon royal and state documents, and are used by governmental departments. They may also appear on other governmental structures built under a particular ruler. For example, the insignia of "N III" for Napoleon III is seen on some Paris bridges, such as the Pont au Change.
Commonwealth realms
The use of a royal cypher in the Commonwealth realms originated in the United Kingdom, where the public use of the royal initials dates at least from the early Tudor period, and was simply the initial of the sovereign with, after Henry VIII's reign, the addition of the letter 'R' for or . The letter 'I' for was added to Queen Victoria's monogram after she became Empress of India in 1877.
The initialswhich had no set pattern or form of lettering laid downwere usually shown in company with the royal arms or crown as on the king's manors and palacessuch as those of Henry VIII on the gatehouse of St James's Palace. The purpose seems to have been simply to identify an individual sovereign, particularly on certain landmarks that he or she has commissioned, as the royal coat of arms in contrast was often used by successive monarchs and is therefore not distinct. The initials are furthermore used on government papers, duty stamps and similar objects, and are surmounted in England by a stylised version of the Tudor Crown or St Edward's Crown; in Scotland the Crown of Scotland is used instead.
Though royal sy
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https://en.wikipedia.org/wiki/Jada%20Toys
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Jada Toys, Inc. is an American manufacturer of collectible scale model cars, figures, radio controlled model vehicles, and dolls. It was founded in 1999 by Jack and May Li. Jada's products are predominantly aimed at the collectible market, and are available and popular at retail outlets worldwide.
The company has or has had license rights to market products from a wide range of entertainment companies and franchises as well as sports associations, including DC Comics, Disney, Marvel Comics, NASCAR, NBA, WWE, Fast & Furious, and Hello Kitty, among others.
History
Founded by Jack and May Li in 1999, Jada's first toy was a 1:24 scale die-cast 1953 Chevrolet tow truck, part of their Thunder Crusher line. Though the Chevrolet tow truck toy and other lines proved successful, the company remained in obscurity until the introduction of the urban-themed DUB City brand. Launched in collaboration with DUB Magazine in 2002, the line presents officially licensed vehicles with custom rims, lowered ride height and special in-car entertainment systems. Dubs, so named for their 20-inch or bigger wheels, are among the company's best sellers and the most visible in retail outlets.
The company launched the DUB City spinoff Chub City in 2005. Targeted at a younger generation of collectors, the line included heavily stylized vehicles and a story told through webisodes and comics. The human characters featured in the story inspired toys of their own. By 2007, the line had done over $12.5 million in sales and was featured in a Burger King kids meal promotion. In 2009, Jada sold the brand to Dentsu Entertainment; who, in conjunction with Fuel Entertainment and Nelvana, planned on launching a $15 million 52-episode animated series in late 2015. At the time of the sale, Chub City toys had sold over 20 million units.
Branching out of automotive licensing, in 2008 Jada Toys teamed up with Activision to release the Guitar Hero Air Guitar Rocker. The toy consists of a belt buckle, a portable
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https://en.wikipedia.org/wiki/Crystal%20engineering
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Crystal engineering studies the design and synthesis of solid-state structures with desired properties through deliberate control of intermolecular interactions. It is an interdisciplinary academic field, bridging solid-state and supramolecular chemistry.
The main engineering strategies currently in use are hydrogen- and halogen bonding and coordination bonding. These may be understood with key concepts such as the supramolecular synthon and the secondary building unit.
History of term
The term 'crystal engineering' was first used in 1955 by R. Pepinsky but the starting point is often credited to Gerhard Schmidt in connection with photodimerization reactions in crystalline cinnamic acids. Since this initial use, the meaning of the term has broadened considerably to include many aspects of solid state supramolecular chemistry. A useful modern definition is that provided by Gautam Desiraju, who in 1988 defined crystal engineering as "the understanding of intermolecular interactions in the context of crystal packing and the utilization of such understanding in the design of new solids with desired physical and chemical properties." Since many of the bulk properties of molecular materials are dictated by the manner in which the molecules are ordered in the solid state, it is clear that an ability to control this ordering would afford control over these properties.
Non-covalent control of structure
Crystal engineering relies on noncovalent bonding to achieve the organization of molecules and ions in the solid state. Much of the initial work on purely organic systems focused on the use of hydrogen bonds, although coordination and halogen bonds provide additional control in crystal design.
Molecular self-assembly is at the heart of crystal engineering, and it typically involves an interaction between complementary hydrogen bonding faces or a metal and a ligand. "Supramolecular synthons" are building blocks that are common to many structures and hence can be use
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https://en.wikipedia.org/wiki/Fujitsu%20Eagle
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The M2351 "Eagle" was a hard disk drive manufactured by Fujitsu with an SMD interface that was used on many servers in the mid-1980s. It offered an unformatted capacity of 470 MB in (6U) of 19-inch rack space, at a retail price of about US$10,000.
The data density, access speed, reliability, use of a standard interface, and price point combined to make it a very popular product used by many system manufacturers, such as Sun Microsystems. The Eagle was also popular at installations of DEC VAX systems, as third-party storage systems were often dramatically more cost-effective and space-dense than those vendor-supplied.
The model 2351A incorporated eleven platters rotating at 3,960 rpm, taking half a minute to spin up. The Eagle used platters, unlike most of its competitors, which still used the standard set in 1962 by the IBM 1311. One moving head accessed each data surface (20 total), one more head was dedicated to the servo mechanism. The model 2351AF added 60 fixed heads (20 surfaces × 3 cylinders) for access to a separate area of 1.7 MB.
The Eagle achieved a data transfer rate of 1.8 MB/s (a contemporary PC disk would only deliver 0.4 MB/s).
Power consumption (of the drive alone) was about 600 watts.
Notes
External links
Computer storage devices
Fujitsu
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https://en.wikipedia.org/wiki/Stereoscopic%20spectroscopy
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Stereoscopic spectroscopy is a type of imaging spectroscopy that can extract a few spectral parameters over a complete image plane simultaneously. A stereoscopic spectrograph is similar to a normal spectrograph except that (A) it has no slit, and (B) multiple spectral orders (often including the non-dispersed zero order) are collected simultaneously. The individual images are blurred by the spectral information present in the original data. The images are recombined using stereoscopic algorithms similar to those used to find ground feature altitudes from parallax in aerial photography.
Stereoscopic spectroscopy is a special case of the more general field of tomographic spectroscopy. Both types of imaging use an analogy between the data space of imaging spectrographs and the conventional 3-space of the physical world. Each spectral order in the instrument produces an image plane analogous to the view from a camera with a particular look angle through the data space, and recombining the views allows recovery of (some aspects of) the spectrum at every location in the image.
Spectroscopy
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https://en.wikipedia.org/wiki/Adaptive%20Simpson%27s%20method
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Adaptive Simpson's method, also called adaptive Simpson's rule, is a method of numerical integration proposed by G.F. Kuncir in 1962. It is probably the first recursive adaptive algorithm for numerical integration to appear in print, although more modern adaptive methods based on Gauss–Kronrod quadrature and Clenshaw–Curtis quadrature are now generally preferred. Adaptive Simpson's method uses an estimate of the error we get from calculating a definite integral using Simpson's rule. If the error exceeds a user-specified tolerance, the algorithm calls for subdividing the interval of integration in two and applying adaptive Simpson's method to each subinterval in a recursive manner. The technique is usually much more efficient than composite Simpson's rule since it uses fewer function evaluations in places where the function is well-approximated by a cubic function.
Simpson's rule is an interpolatory quadrature rule which is exact when the integrand is a polynomial of degree three or lower. Using Richardson extrapolation, the more accurate Simpson estimate for six function values is combined with the less accurate estimate for three function values by applying the correction . So, the obtained estimate is exact for polynomials of degree five or less.
Mathematical Procedure
Defining Terms
A criterion for determining when to stop subdividing an interval, suggested by J.N. Lyness, is
where is an interval with midpoint , while , , and given by Simpson's rule are the estimates of , , and respectively, and is the desired maximum error tolerance for the interval.
Note, .
Procedural Steps
To perform adaptive Simpson's method, do the following: if , add and to the sum of Simpson's rules which are used to approximate the integral, otherwise, perform the same operation with and instead of .
Numerical consideration
Some inputs will fail to converge in adaptive Simpson's method quickly, resulting in the tolerance underflowing and producing an infinite loop.
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https://en.wikipedia.org/wiki/Asplenia%20with%20cardiovascular%20anomalies
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Asplenia with cardiovascular anomalies, also known as Ivemark syndrome and right atrial isomerism, is an example of a heterotaxy syndrome. These uncommon congenital disorders are characterized by defects in the heart, spleen and paired organs such as the lungs and kidneys. Another name is "asplenia-cardiovascular defect-heterotaxy".
Right atrial isomerism is named for its discoverer, Swedish pathologist Biörn Ivemark.
Presentation
In right atrial isomerism, both atria of the heart are morphological right atria leading to associated abnormalities in the pulmonary venous system. In addition, individuals with right atrial isomerism develop asplenia, a midline liver, malrotation of the small intestine and the presence of two morphologic right lungs. Individuals with left atrial isomerism, by comparison, have two morphologic left atria, polysplenia, intestinal malrotation and two morphologic left lungs.
The majority of cases present at the time of birth or within a few days or weeks. Presenting signs and symptoms of the congenital heart defect may include cyanosis, breathlessness, lethargy and poor feeding.
Causes
The cause of heterotaxy is unknown.
The Ivemark Syndrome Association, which is based in Dorset, is one of the organisations dedicated to helping patients and funding research.
Diagnosis
Treatment
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https://en.wikipedia.org/wiki/Affectional%20bond
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In psychology, an affectional bond is a type of attachment behavior one individual has for another individual, typically a caregiver for her or his child, in which the two partners tend to remain in proximity to one another. The term was coined and subsequently developed over the course of four decades, from the early 1940s to the late 1970s, by psychologist John Bowlby in his work on attachment theory. The core of the term affectional bond, according to Bowlby, is the attraction one individual has for another individual. The central features of the concept of affectional bonding can be traced to Bowlby's 1958 paper, "The Nature of the Child's Tie to his Mother".
Five criteria
Bowlby referred to attachment bonds as a specific type of "affectional" bond, as described by him and developmental psychologist Mary Ainsworth. She established five criteria for affectional bonds between individuals, and a sixth criterion for attachment bonds:
An affectional bond is persistent, not transitory.
An affectional bond involves a particular person who is not interchangeable with anyone else.
An affectional bond involves a relationship that is emotionally significant.
The individual wishes to maintain proximity or contact with the person with whom he or she has an affectional tie.
The individual feels sadness or distress at involuntary separation from the person.
(Attachment bond) The individual feels lonely & can not form other long lasting relationships & friendships.
An attachment bond has an additional criterion: the person seeks security and comfort in the relationship.
Attachment theory
Background
Bowlby believed that there were four distinguishing characteristics of attachment. These included:
Proximity Maintenance: The desire to be near the people we are attached to.
Safe Haven: Returning to the attachment figure for comfort and safety in the face of fear or threat.
Secure Base: The attachment figure acts as a base of security from which the child can explore the
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https://en.wikipedia.org/wiki/Bicycle%20and%20motorcycle%20dynamics
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Bicycle and motorcycle dynamics is the science of the motion of bicycles and motorcycles and their components, due to the forces acting on them. Dynamics falls under a branch of physics known as classical mechanics. Bike motions of interest include balancing, steering, braking, accelerating, suspension activation, and vibration. The study of these motions began in the late 19th century and continues today.
Bicycles and motorcycles are both single-track vehicles and so their motions have many fundamental attributes in common and are fundamentally different from and more difficult to study than other wheeled vehicles such as dicycles, tricycles, and quadracycles. As with unicycles, bikes lack lateral stability when stationary, and under most circumstances can only remain upright when moving forward. Experimentation and mathematical analysis have shown that a bike stays upright when it is steered to keep its center of mass over its wheels. This steering is usually supplied by a rider, or in certain circumstances, by the bike itself. Several factors, including geometry, mass distribution, and gyroscopic effect all contribute in varying degrees to this self-stability, but long-standing hypotheses and claims that any single effect, such as gyroscopic or trail, is solely responsible for the stabilizing force have been discredited.
While remaining upright may be the primary goal of beginning riders, a bike must lean in order to maintain balance in a turn: the higher the speed or smaller the turn radius, the more lean is required. This balances the roll torque about the wheel contact patches generated by centrifugal force due to the turn with that of the gravitational force. This lean is usually produced by a momentary steering in the opposite direction, called countersteering. Countersteering skill is usually acquired by motor learning and executed via procedural memory rather than by conscious thought. Unlike other wheeled vehicles, the primary control input on bikes is
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https://en.wikipedia.org/wiki/Fetch%21%20with%20Ruff%20Ruffman
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Fetch! with Ruff Ruffman (sometimes shortened as Fetch!) is an American live-action/animated television series that aired on PBS Kids Go! and is largely targeted toward children ages 6–10. It is a reality-game show that is hosted by an animated anthropomorphic dog named Ruff Ruffman who dispenses challenges to the show's real-life contestants. The series ran for five seasons and 100 episodes from May 29, 2006, to November 4, 2010, on PBS, with 30 contestants in that time. Although a sixth season was planned, with auditions taking place in January 2010, WGBH announced on June 14, 2010, that due to lack of funding, the series would end. In June 2008, the series received its first Emmy for Best Original Song for its theme.
Synopsis
Fetch! is a reality-based game show where young contestants (ages 10–14) take on various challenges to gain points. During these challenges, the contestants must complete a variety of tasks assigned to them ahead of time (and on the fly) by Ruff and surrogates, depending on the situation. There is also an educational component, as contestants often must learn something (i.e. Astronomy, Puzzles, Carpentry, Engineering, Food Science, Biology, Chemistry, Physics, Mathematics, etc.) in order to complete the task.
Not all contestants leave the studio each episode to complete tasks. "As determined by the Fetch 3000" (according to Ruff), the contestants who remain behind in the studio participate in the "Half-Time Quiz Show", in which Ruff asks them up to ten questions with the limited time based on the activities of the contestants out on challenges. Out on challenges, contestants will have the potential to earn up to 100 points. The contestants in the studio will have a chance to win a maximum of 50 in the "Half-Time Quiz Show". The show has a Fetch Fairness Guarantee; that every contestant will "compete for the same number of points" through thirteen challenges and six "Half-time Quiz Shows" before the final episode. Additionally, Ruff assig
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https://en.wikipedia.org/wiki/Exterior%20gateway%20protocol
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An exterior gateway protocol is an IP routing protocol used to exchange routing information between autonomous systems. This exchange is crucial for communications across the Internet. Notable exterior gateway protocols include Exterior Gateway Protocol (EGP), now obsolete, and Border Gateway Protocol (BGP).
By contrast, an interior gateway protocol is a type of protocol used for exchanging routing information between gateways (commonly routers) within an autonomous system (for example, a system of corporate local area networks). This routing information can then be used to route network-level protocols like IP.
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https://en.wikipedia.org/wiki/Accounting%20liquidity
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In accounting, liquidity (or accounting liquidity) is a measure of the ability of a debtor to pay their debts as and when they fall due. It is usually expressed as a ratio or a percentage of current liabilities. Liquidity is the ability to pay short-term obligations.
Calculating liquidity
For a corporation with a published balance sheet there are various ratios used to calculate a measure of liquidity. These include the following:
The current ratio is the simplest measure and calculated by dividing the total current assets by the total current liabilities. A value of over 100% is normal in a non-banking corporation. However, some current assets are more difficult to sell at full value in a hurry.
The quick ratio is calculated by deducting inventories and prepayments from current assets and then dividing by current liabilities, giving a measure of the ability to meet current liabilities from assets that can be readily sold. A better way for a trading corporation to meet liabilities is from cash flows, rather than through asset sales, so;
The operating cash flow ratio can be calculated by dividing the operating cash flow by current liabilities. This indicates the ability to service current debt from current income, rather than through asset sales.
Understanding the ratios
For different industries and differing legal systems the use of differing ratios and results would be appropriate. For instance, in a country with a legal system that gives a slow or uncertain result a higher level of liquidity would be appropriate to cover the uncertainty related to the valuation of assets. A manufacturer with stable cash flows may find a lower quick ratio more appropriate than an Internet-based start-up corporation.
Liquidity in banking
Liquidity is a prime concern in a banking environment and a shortage of liquidity has often been a trigger for bank failures. Holding assets in a highly liquid form tends to reduce the income from that asset (cash, for example, is the most l
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https://en.wikipedia.org/wiki/Linear%E2%80%93quadratic%20regulator
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The theory of optimal control is concerned with operating a dynamic system at minimum cost. The case where the system dynamics are described by a set of linear differential equations and the cost is described by a quadratic function is called the LQ problem. One of the main results in the theory is that the solution is provided by the linear–quadratic regulator (LQR), a feedback controller whose equations are given below.
LQR controllers possess inherent robustness with guaranteed gain and phase margin, and they also are part of the solution to the LQG (linear–quadratic–Gaussian) problem. Like the LQR problem itself, the LQG problem is one of the most fundamental problems in control theory.
General description
The settings of a (regulating) controller governing either a machine or process (like an airplane or chemical reactor) are found by using a mathematical algorithm that minimizes a cost function with weighting factors supplied by a human (engineer). The cost function is often defined as a sum of the deviations of key measurements, like altitude or process temperature, from their desired values. The algorithm thus finds those controller settings that minimize undesired deviations. The magnitude of the control action itself may also be included in the cost function.
The LQR algorithm reduces the amount of work done by the control systems engineer to optimize the controller. However, the engineer still needs to specify the cost function parameters, and compare the results with the specified design goals. Often this means that controller construction will be an iterative process in which the engineer judges the "optimal" controllers produced through simulation and then adjusts the parameters to produce a controller more consistent with design goals.
The LQR algorithm is essentially an automated way of finding an appropriate state-feedback controller. As such, it is not uncommon for control engineers to prefer alternative methods, like full state feedback, al
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https://en.wikipedia.org/wiki/Chrome%20S20%20series
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Chrome 20 Series is a graphics accelerator by S3 Graphics, the successor of GammaChrome S18.
Overview
The Chrome 20 series was introduced on March 11, 2005, with the Chrome S25 and Chrome S27 as launch products. Similar to the GammaChrome S18 PCI Express which preceded it, S20 was marketed to the low and mid range of the graphics card market, with the Chromotion 3 Video Engine and low power consumption as main selling points.
The S20 series marked S3's first products utilizing Fujitsu's 90 nm process. This enabled a significant increase in clock speeds over prior S3 products, and the Chrome 20 series could use 32-256MiB GDDR1 or GDDR3 memory at maximum if 700 MHz, or 64-512MiB GDDR2 memory at a maximum of 500 MHz. The S20 was also S3's first GDDR3 enabled product - with the memory interface supporting 32, 64, or 128-bit of GDDR1, GDDR2 or GDDR3 memory.
Similar to Radeon X1000 series, texturing units and raster operators are separated from pixel shaders. Chrome 20 has 4 vertex shaders, 8 pixel shaders, 4 texturing units, 4 raster operators.
Display controller now integrates a single-link TMDS transmitter, with support of dual-link using external transmitters.
Other new features supports the multi-GPU technology MultiChrome and AcceleRAM.
Chromotion 3.0
This revision of Chromotion Engine adds support of nonlinear video scaling, commonly used by wide screen television sets. TV encoder now supports 18 DTV ATSC formats:
MultiChrome
MultiChrome is a technique to couple multiple graphics chips for better performance. It was first used in the Chrome S20 series and later in Chrome 400 series graphics processors. The methods used by MultiChome are Alternate frame rendering and Split Frame Rendering. The technology is comparable to NVidia's SLI and ATi/AMD's Crossfire multi video adapter solution.
At the moment, due to the speed of the Chrome S20 and Chrome 400 chipsets, no special connectors are required to bridge both cards to activate MultiChrome. Also, unlike NVid
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https://en.wikipedia.org/wiki/Posaconazole
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Posaconazole, sold under the brand name Noxafil among others, is a triazole antifungal medication.
It was approved for medical use in the United States in September 2006, and is available as a generic medication.
Medical uses
Posaconazole is used to treat invasive Aspergillus and Candida infections. It is also used for the treatment of oropharyngeal candidiasis (OPC), including OPC refractory to itraconazole and/or fluconazole therapy.
It is also used to treat invasive infections by Candida, Mucor, and Aspergillus species in severely immunocompromised patients.
Clinical evidence for its utility in treatment of invasive disease caused by Fusarium species (fusariosis) is limited.
It appears to be helpful in a mouse model of naegleriasis.
Pharmacology
Pharmacodynamics
Posaconazole works by disrupting the close packing of acyl chains of phospholipids, impairing the functions of certain membrane-bound enzyme systems such as ATPase and enzymes of the electron transport system, thus inhibiting growth of the fungi. It does this by blocking the synthesis of ergosterol by inhibiting of the enzyme lanosterol 14α-demethylase and accumulation of methylated sterol precursors. Posaconazole is significantly more potent at inhibiting 14-alpha demethylase than itraconazole.
Microbiology
Posaconazole is active against the following microorganisms:
Candida spp.
Aspergillus spp.
Zygomycetes spp.
Pharmacokinetics
Posaconazole is absorbed within three to five hours. It is predominantly eliminated through the liver, and has a half-life of about 35 hours. Oral administration of posaconazole taken with a high-fat meal exceeds 90% bioavailability and increases the concentration by four times compared to fasting state.
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https://en.wikipedia.org/wiki/Linear%E2%80%93quadratic%E2%80%93Gaussian%20control
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In control theory, the linear–quadratic–Gaussian (LQG) control problem is one of the most fundamental optimal control problems, and it can also be operated repeatedly for model predictive control. It concerns linear systems driven by additive white Gaussian noise. The problem is to determine an output feedback law that is optimal in the sense of minimizing the expected value of a quadratic cost criterion. Output measurements are assumed to be corrupted by Gaussian noise and the initial state, likewise, is assumed to be a Gaussian random vector.
Under these assumptions an optimal control scheme within the class of linear control laws can be derived by a completion-of-squares argument. This control law which is known as the LQG controller, is unique and it is simply a combination of a Kalman filter (a linear–quadratic state estimator (LQE)) together with a linear–quadratic regulator (LQR). The separation principle states that the state estimator and the state feedback can be designed independently. LQG control applies to both linear time-invariant systems as well as linear time-varying systems, and constitutes a linear dynamic feedback control law that is easily computed and implemented: the LQG controller itself is a dynamic system like the system it controls. Both systems have the same state dimension.
A deeper statement of the separation principle is that the LQG controller is still optimal in a wider class of possibly nonlinear controllers. That is, utilizing a nonlinear control scheme will not improve the expected value of the cost function. This version of the separation principle is a special case of the separation principle of stochastic control which states that even when the process and output noise sources are possibly non-Gaussian martingales, as long as the system dynamics are linear, the optimal control separates into an optimal state estimator (which may no longer be a Kalman filter) and an LQR regulator.
In the classical LQG setting, implementation
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https://en.wikipedia.org/wiki/Aeromonas
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Aeromonas is a genus of Gram-negative, facultative anaerobic, rod-shaped, bacteria that morphologically resemble members of the family Enterobacteriaceae. Most of the 14 described species have been associated with human diseases. The most important pathogens are A. hydrophila, A. caviae, and A. veronii biovar sobria. The organisms are ubiquitous in fresh and brackish water.
They group with the gamma subclass of the Proteobacteria.
Two major diseases associated with Aeromonas are gastroenteritis and wound infections, with or without bacteremia. Gastroenteritis typically occurs after the ingestion of contaminated water or food, whereas wound infections result from exposure to contaminated water. In its most severe form, Aeromonas spp. can cause necrotizing fasciitis, which is life-threatening, usually requiring treatment with antibiotics and even amputation.
Although some potential virulence factors (e.g. endotoxins, hemolysins, enterotoxins, adherence factors) have been identified, their precise roles are unknown.
Association with human diarrhea and human intestinal infections
Literature exists on this subject, but many papers have not adequately studied the causal role of the Aeromonas strain(s) that were isolated from the cases that were studied. The presence of an Aeromonas strain in a fecal specimen does not prove or even imply that the strain was causing the diarrhea. Gastrointestinal disease in children is usually an acute, severe illness, whereas that in adults tends to be chronic diarrhea. Severe Aeromonas gastroenteritis resembles shigellosis, with blood and leukocytes in the stool. Acute diarrheal disease is self-limited, and only supportive care is indicated in affected patients.
Wound infection
Wound infections are the second-most common type of human infection associated with Aeromonas. They are associated with penetrating wounds or abrasions that place the wound in contact with fresh water or soil.
Medicinal leeches
Aeromonas species are endosym
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https://en.wikipedia.org/wiki/Controllability%20Gramian
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In control theory, we may need to find out whether or not a system such as
is controllable, where , , and are, respectively, , , and matrices for a system with inputs, state variables and outputs.
One of the many ways one can achieve such goal is by the use of the Controllability Gramian.
Controllability in LTI Systems
Linear Time Invariant (LTI) Systems are those systems in which the parameters , , and are invariant with respect to time.
One can observe if the LTI system is or is not controllable simply by looking at the pair . Then, we can say that the following statements are equivalent:
1. The pair is controllable.
2. The matrix
is nonsingular for any .
3. The controllability matrix
has rank n.
4. The matrix
has full row rank at every eigenvalue of .
If, in addition, all eigenvalues of have negative real parts ( is stable), and the unique solution of the Lyapunov equation
is positive definite, the system is controllable. The solution is called the Controllability Gramian and can be expressed as
In the following section we are going to take a closer look at the Controllability Gramian.
Controllability Gramian
The controllability Gramian can be found as the solution of the Lyapunov equation given by
In fact, we can see that if we take
as a solution, we are going to find that:
Where we used the fact that at for stable (all its eigenvalues have negative real part). This shows us that is indeed the solution for the Lyapunov equation under analysis.
Properties
We can see that is a symmetric matrix, therefore, so is .
We can use again the fact that, if is stable (all its eigenvalues have negative real part) to show that is unique. In order to prove so, suppose we have two different solutions for
and they are given by and . Then we have:
Multiplying by by the left and by by the right, would lead us to
Integrating from to :
using the fact that as :
In other words, has to be unique.
Also, we can see that
is positi
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https://en.wikipedia.org/wiki/Observability%20Gramian
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In control theory, we may need to find out whether or not a system such as
is observable, where , , and are, respectively, , , and matrices.
One of the many ways one can achieve such goal is by the use of the Observability Gramian.
Observability in LTI Systems
Linear Time Invariant (LTI) Systems are those systems in which the parameters , , and are invariant with respect to time.
One can determine if the LTI system is or is not observable simply by looking at the pair . Then, we can say that the following statements are equivalent:
1. The pair is observable.
2. The matrix
is nonsingular for any .
3. The observability matrix
has rank n.
4. The matrix
has full column rank at every eigenvalue of .
If, in addition, all eigenvalues of have negative real parts ( is stable) and the unique solution of
is positive definite, then the system is observable. The solution is called the Observability Gramian and can be expressed as
In the following section we are going to take a closer look at the Observability Gramian.
Observability Gramian
The Observability Gramian can be found as the solution of the Lyapunov equation given by
In fact, we can see that if we take
as a solution, we are going to find that:
Where we used the fact that at for stable (all its eigenvalues have negative real part). This shows us that is indeed the solution for the Lyapunov equation under analysis.
Properties
We can see that is a symmetric matrix, therefore, so is .
We can use again the fact that, if is stable (all its eigenvalues have negative real part) to show that is unique. In order to prove so, suppose we have two different solutions for
and they are given by and . Then we have:
Multiplying by by the left and by by the right, would lead us to
Integrating from to :
using the fact that as :
In other words, has to be unique.
Also, we can see that
is positive for any (assuming the non-degenerate case where is not identically zero), and that makes
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https://en.wikipedia.org/wiki/Rocky%20shore
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A rocky shore is an intertidal area of seacoasts where solid rock predominates. Rocky shores are biologically rich environments, and are a useful "natural laboratory" for studying intertidal ecology and other biological processes. Due to their high accessibility, they have been well studied for a long time and their species are well known.
Marine life
Many factors favour the survival of life on rocky shores. Temperate coastal waters are mixed by waves and convection, maintaining adequate availability of nutrients. Also, the sea brings plankton and broken organic matter in with each tide. The high availability of light (due to low depths) and nutrient levels means that primary productivity of seaweeds and algae can be very high. Human actions can also benefit rocky shores due to nutrient runoff.
Despite these favourable factors, there are also a number of challenges to marine organisms associated with the rocky shore ecosystem. Generally, the distribution of benthic species is limited by salinity, wave exposure, temperature, desiccation and general stress. The constant threat of desiccation during exposure at low tide can result in dehydration. Hence, many species have developed adaptations to prevent this drying out, such as the production of mucous layers and shells. Many species use shells and holdfasts to provide stability against strong wave actions. There are also a variety of other challenges such as temperature fluctuations due to tidal flow (resulting in exposure), changes in salinity and various ranges of illumination. Other threats include predation from birds and other marine organisms, as well as the effects of pollution.
Ballantine Scale
The Ballantine scale is a biologically defined scale for measuring the degree of exposure level of wave action on a rocky shore. Devised in 1961 by W. J. Ballantine, then at the zoology department of Queen Mary University of London, London, U.K., the scale is based on the observation that where shoreline species a
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https://en.wikipedia.org/wiki/GUS%20reporter%20system
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The GUS reporter system (GUS: β-glucuronidase) is a reporter gene system, particularly useful in plant molecular biology and microbiology. Several kinds of GUS reporter gene assay are available, depending on the substrate used. The term GUS staining refers to the most common of these, a histochemical technique.
Purpose
The purpose of this technique is to analyze the activity of a gene transcription promoter (in terms of expression of a so-called reporter gene under the regulatory control of that promoter) either in a quantitative manner, involving some measure of activity, or qualitatively (on versus off) through visualization of its activity in different cells, tissues, or organs. The technique utilizes the uidA gene of Escherichia coli, which codes for the enzyme, β-glucuronidase; this enzyme, when incubated with specific colorless or non-fluorescent substrates, can convert them into stable colored or fluorescent products. The presence of the GUS-induced color indicates where the gene has been actively expressed. In this way, strong promoter activity produces much staining and weak promoter activity produces less staining.
The uidA gene can also be fused to a gene of interest, creating a gene fusion. The insertion of the uidA gene will cause production of GUS, which can then be detected using various glucuronides as substrates.
Substrates
There are different possible glucuronide that can be used as substrates for the β-glucuronidase, depending on the type of detection needed (histochemical, spectrophotometrical, fluorimetrical). The most common substrate for GUS histochemical staining is 5-bromo-4-chloro-3-indolyl glucuronide (X-Gluc). X-Gluc is hydrolyzed by GUS into the product 5,5'-dibromo-4,4'-dichloro-indigo (diX-indigo). DiX-indigo will appear blue, and can be seen using light microscopy. This process is analogous to hydrolysis of X-gal by Beta-galactosidase to produce blue cells as is commonly practiced in bacterial reporter gene assays.
For other typ
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https://en.wikipedia.org/wiki/Mus%C3%A9e%20du%20Vin
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The Musée du Vin (in ) is a cultural venue in the 16th arrondissement located at 5, square Charles Dickens, Paris, France next to the Trocadéro and the Eiffel Tower. The nearest métro station is Passy. It opened in 1984.
Overview
The museum testifies to the richness and diversity of the French craft of winemaking, through an exposure to tools and objects used to work the grapevine and the wine. The collection is shown in an old setting from the Middle Ages and arranged later in storerooms by the Order of the Minims of the Convent of Passy.
History
Formerly, the hill where the winding galleries of the Wine Museum are located was covered by the vast oak forest. Around the 6th century, Nigeon village was growing on the heights of Chaillot, with its crops, vineyards and quarries.
In 1493, monks settled here. The area of their community extended to the present-day Water Street (Rue des Eaux). The building of the Abbaye de Passy began. The monks cultivated a few acres of vineyards in a closed street, which exist to this day. In the hill, they discovered ancient quarries where they created the cellars of the Abbey.
From the 17th century, Rue des Eaux is open water and allows visitors to access the Museum. The name of the street refers to the mineral springs found there and was in great vogue until 1785. Today, visitors can peer at it through a well shaft. The French Revolution of 1789 removed the religious orders in 1790 and terminated the life of the Abbey, which was gradually destroyed. Rediscovered a few years ago, the Wine Museum opened to the public in 1984.
The Paris Wine Museum is twinned with the Valais Vine and Wine Museum in Switzerland. The ceremony formalizing this pairing took place in March 2010 at the Paris Wine Museum.
Description
The wine museum is located in old quarries of the Middle Ages, which were used as cellars in the 15th century. The brothers of the convent of the Minims (Passy) then produced wine very popular with King Louis XIII, from
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https://en.wikipedia.org/wiki/Evolution%20of%20molluscs
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The evolution of the molluscs is the way in which the Mollusca, one of the largest groups of invertebrate animals, evolved. This phylum includes gastropods, bivalves, scaphopods, cephalopods, and several other groups.
The fossil record of mollusks is relatively complete, and they are well represented in most fossil-bearing marine strata. Very early organisms which have dubiously been compared to molluscs include Kimberella and Odontogriphus.
Fossil record
Good evidence exists for the appearance of gastropods, cephalopods and bivalves in the Cambrian period . However, the evolutionary history both of the emergence of molluscs from the ancestral group Lophotrochozoa, and of their diversification into the well-known living and fossil forms, is still vigorously debated.
Debate occurs about whether some Ediacaran and Early Cambrian fossils really are molluscs. Kimberella, from about , has been described by some paleontologists as "mollusc-like", but others are unwilling to go further than "probable bilaterian". There is an even sharper debate about whether Wiwaxia, from about , was a mollusc, and much of this centers on whether its feeding apparatus was a type of radula or more similar to that of some polychaete worms. Nicholas Butterfield, who opposes the idea that Wiwaxia was a mollusc, has written that earlier microfossils from are fragments of a genuinely mollusc-like radula. This appears to contradict the concept that the ancestral molluscan radula was mineralized.
However, the Helcionellids, which first appear over in Early Cambrian rocks from Siberia and China, are thought to be early molluscs with rather snail-like shells. Shelled molluscs therefore predate the earliest trilobites. Although most helcionellid fossils are only a few millimeters long, specimens a few centimeters long have also been found, most with more limpet-like shapes. The tiny specimens have been suggested to be juveniles and the larger ones adults.
Some analyses of helcionellids conclu
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https://en.wikipedia.org/wiki/Syringa%20%C3%97%20laciniata
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Syringa × laciniata, the cut-leaf lilac or cutleaf lilac, is a hybrid lilac of unknown, though old origin. It is thought to be a hybrid between Syringa vulgaris from southeastern Europe and Syringa protolaciniata from western China. Although often cited as being from China, it more likely arose somewhere in southwestern Asia, where it was first scientifically described from cultivated plants in the 17th century, possibly Iran or Afghanistan, or Pakistan, where it has been cultivated since ancient times.
It is a deciduous shrub growing to 2 m tall. The leaves are 2–4 cm long, variably entire or cut deeply into three to nine lobes or leaflets. The flowers are pale lilac, produced in loose panicles up to 7 cm long in mid spring. It is hardy to USDA plant hardiness zone 5.
See also
Syringa × persica
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https://en.wikipedia.org/wiki/Avagraha
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Avagraha () is a symbol used to indicate prodelision of an () in many Indian languages like Sanskrit as shown below. It is usually transliterated with an apostrophe in Roman script and, in case of Devanagari, as in the Sanskrit philosophical expression (), which is a sandhi of ( + ) ‘I am Shiva’. The avagraha is also used for prolonging vowel sounds in some languages, for example Hindi for ‘Mā̃ā̃ā̃ā̃!’ when calling to one's mother, or when transliterating foreign words in instant messaging: for example, 'cool' can be transliterated as .
In the case of Hindi, the character is also sometimes used as a symbol to denote long or heavy syllables, in metrical poetry. For example, the syllables in the word ‘metre’ (in nominative) can be denoted as "", meaning two long syllables. (Cf. other notations in entry "Systems of scansion".)
Avagraha in Unicode
The avagraha symbol is encoded at several Unicode points, for various Brahmic scripts that use it.
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https://en.wikipedia.org/wiki/Sternopericardial%20ligaments
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The fibrous pericardium is attached to the posterior surface of the sternum by the superior and inferior sternopericardiac ligaments (sternopericardial ligaments); the upper passing to the manubrium, and the lower to the xiphoid process.
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https://en.wikipedia.org/wiki/Pectinate%20muscles
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The pectinate muscles (musculi pectinati) are parallel muscular ridges in the walls of the atria of the heart.
Structure
Behind the crest (crista terminalis) of the right atrium the internal surface is smooth. Pectinate muscles make up the part of the wall in front of this, the right atrial appendage.
In the left atrium, the pectinate muscles are confined to the inner surface of its atrial appendage. They tend to be fewer and smaller than in the right atrium. This is due to the embryological origin of the auricles, which are the true atria. Some sources cite that the pectinate muscles are useful in increasing the power of contraction without increasing heart mass substantially.
Pectinate muscles of the atria are different from the trabeculae carneae, which are found on the inner walls of both ventricles. The pectinate muscles originate from the crista terminalis.
Name
The pectinate muscles are so-called because of their resemblance to the teeth of a comb, as in pecten.
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https://en.wikipedia.org/wiki/Gibbs%20isotherm
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The Gibbs adsorption isotherm for multicomponent systems is an equation used to relate the changes in concentration of a component in contact with a surface with changes in the surface tension, which results in a corresponding change in surface energy. For a binary system, the Gibbs adsorption equation in terms of surface excess is:
where
is the surface tension,
i is the surface excess concentration of component i,
i is the chemical potential of component i.
Adsorption
Different influences at the interface may cause changes in the composition of the near-surface layer. Substances may either accumulate near the surface or, conversely, move into the bulk. The movement of the molecules characterizes the phenomena of adsorption. Adsorption influences changes in surface tension and colloid stability. Adsorption layers at the surface of a liquid dispersion medium may affect the interactions of the dispersed particles in the media and consequently these layers may play crucial role in colloid stability The adsorption of molecules of liquid phase at an interface occurs when this liquid phase is in contact with other immiscible phases that may be gas, liquid, or solid
Conceptual explanation of equation
Surface tension describes how difficult it is to extend the area of a surface (by stretching or distorting it). If surface tension is high, there is a large free energy required to increase the surface area, so the surface will tend to contract and hold together like a rubber sheet.
There are various factors affecting surface tension, one of which is that the composition of the surface may be different from the bulk. For example, if water is mixed with a tiny amount of surfactants (for example, hand soap), the bulk water may be 99% water molecules and 1% soap molecules, but the topmost surface of the water may be 50% water molecules and 50% soap molecules. In this case, the soap has a large and positive "surface excess". In other examples, the surface excess may be
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https://en.wikipedia.org/wiki/Central%20tendon%20of%20diaphragm
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The central tendon of the diaphragm is a thin but strong aponeurosis situated slightly anterior to the vault formed by the muscle, resulting in longer posterior muscle fibers.
It is inferior to the fibrous pericardium, which fuses with the central tendon of the diaphragm via the pericardiacophrenic ligament.
The caval opening (at the level of the T8 vertebra) passes through the central tendon. This transmits the inferior vena cava and right phrenic nerve.
Structure
The central tendon is shaped somewhat like a trefoil leaf, consisting of three divisions or leaflets separated from one another by slight indentations. The right leaflet is the largest, the middle (directed toward the xiphoid process) the next in size, and the left the smallest.
The central tendon is composed of several planes of fibers, which intersect one another at various angles and unite into straight or curved bundles—an arrangement which gives it additional strength.
Action during respiration
During inspiration, the diaphragm contracts, causing the central tendon to be drawn inferiorly which partially flattens the domes bilaterally. The result is an increase in the thoracic volume and a reduction in intra-thoracic pressure. This reduction allows air to enter the lungs, enhancing venous return. During inspiration, the central tendon retains its shape due to its tendinous nature, and prevents constriction of the inferior vena cava.
Clinical significance
Rarely, a central tendon defect may be involved in a central congenital diaphragmatic hernia. This may be repaired with thoracoscopic surgery.
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https://en.wikipedia.org/wiki/Right%20border%20of%20heart
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The right border of the heart (right margin of heart) is a long border on the surface of the heart, and is formed by the right atrium.
The atrial portion is rounded and almost vertical; it is situated behind the third, fourth, and fifth right costal cartilages about 1.25 cm. from the margin of the sternum.
The ventricular portion, thin and sharp, is named the acute margin; it is nearly horizontal, and extends from the sternal end of the sixth right coastal cartilage to the apex of the heart.
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https://en.wikipedia.org/wiki/Pinch%20%28plasma%20physics%29
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A pinch (or: Bennett pinch (after Willard Harrison Bennett), electromagnetic pinch, magnetic pinch, pinch effect, or plasma pinch.) is the compression of an electrically conducting filament by magnetic forces, or a device that does such. The conductor is usually a plasma, but could also be a solid or liquid metal. Pinches were the first type of device used for experiments in controlled nuclear fusion power.
Pinches occur naturally in electrical discharges such as lightning bolts, planetary auroras, current sheets, and solar flares.
Basic mechanism
Types
Pinches exist in nature and in laboratories. Pinches differ in their geometry and operating forces. These include:
Uncontrolled – Any time an electric current moves in large amounts (e.g., lightning, arcs, sparks, discharges) a magnetic force can pull together plasma. This can be insufficient for fusion.
Sheet pinch – An astrophysical effect, this arises from vast sheets of charged particles.
Z-pinch – The current runs down the axis, or walls, of a cylinder while the magnetic field is azimuthal
Theta pinch – The magnetic field runs down the axis of a cylinder, while the electric field is in the azimuthal direction (also called a thetatron)
Screw pinch – A combination of a Z-pinch and theta pinch (also called a stabilized Z-pinch, or θ-Z pinch)
Reversed field pinch or toroidal pinch – This is a Z-pinch arranged in the shape of a torus. The plasma has an internal magnetic field. As distance increases from the center of this ring, the magnetic field reverses direction.
Inverse pinch – An early fusion concept, this device consisted of a rod surrounded by plasma. Current traveled through the plasma and returned along the center rod. This geometry was slightly different than a z-pinch in that the conductor was in the center, not the sides.
Cylindrical pinch
Orthogonal pinch effect
Ware pinch – A pinch that occurs inside a Tokamak plasma, when particles inside the banana orbit condense together.
Magnetized Li
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https://en.wikipedia.org/wiki/Turbulence%20kinetic%20energy
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In fluid dynamics, turbulence kinetic energy (TKE) is the mean kinetic energy per unit mass associated with eddies in turbulent flow. Physically, the turbulence kinetic energy is characterised by measured root-mean-square (RMS) velocity fluctuations. In the Reynolds-averaged Navier Stokes equations, the turbulence kinetic energy can be calculated based on the closure method, i.e. a turbulence model.
Generally, the TKE is defined to be half the sum of the variances (square of standard deviations) of the velocity components:
where the turbulent velocity component is the difference between the instantaneous and the average velocity , whose mean and variance are respectively.
TKE can be produced by fluid shear, friction or buoyancy, or through external forcing at low-frequency eddy scales (integral scale). Turbulence kinetic energy is then transferred down the turbulence energy cascade, and is dissipated by viscous forces at the Kolmogorov scale. This process of production, transport and dissipation can be expressed as:
where:
is the mean-flow material derivative of TKE;
is the turbulence transport of TKE;
is the production of TKE, and
is the TKE dissipation.
Assuming that molecular viscosity is constant, and making the Boussinesq approximation, the TKE equation is:
By examining these phenomena, the turbulence kinetic energy budget for a particular flow can be found.
Computational fluid dynamics
In computational fluid dynamics (CFD), it is impossible to numerically simulate turbulence without discretizing the flow-field as far as the Kolmogorov microscales, which is called direct numerical simulation (DNS). Because DNS simulations are exorbitantly expensive due to memory, computational and storage overheads, turbulence models are used to simulate the effects of turbulence. A variety of models are used, but generally TKE is a fundamental flow property which must be calculated in order for fluid turbulence to be modelled.
Reynolds-averaged Navier–Stokes
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https://en.wikipedia.org/wiki/Self-consistent%20mean%20field%20%28biology%29
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The self-consistent mean field (SCMF) method is an adaptation of mean field theory used in protein structure prediction to determine the optimal amino acid side chain packing given a fixed protein backbone. It is faster but less accurate than dead-end elimination and is generally used in situations where the protein of interest is too large for the problem to be tractable by DEE.
General principles
Like dead-end elimination, the SCMF method explores conformational space by discretizing the dihedral angles of each side chain into a set of rotamers for each position in the protein sequence. The method iteratively develops a probabilistic description of the relative population of each possible rotamer at each position, and the probability of a given structure is defined as a function of the probabilities of its individual rotamer components.
The basic requirements for an effective SCMF implementation are:
A well-defined finite set of discrete independent variables
A precomputed numerical value (considered the "energy") associated with each element in the set of variables, and associated with each binary element pair
An initial probability distribution describing the starting population of each individual rotamer
A way of updating rotamer energies and probabilities as a function of the mean-field energy
The process is generally initialized with a uniform probability distribution over the rotamers—that is, if there are rotamers at the position in the protein, then the probability of any individual rotamer is . The conversion between energies and probabilities is generally accomplished via the Boltzmann distribution, which introduces a temperature factor (thus making the method amenable to simulated annealing). Lower temperatures increase the likelihood of converging to a single solution, rather than to a small subpopulation of solutions.
Mean-field energies
The energy of an individual rotamer is dependent on the "mean-field" energy of the other positions—tha
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https://en.wikipedia.org/wiki/Harish-Chandra%20isomorphism
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In mathematics, the Harish-Chandra isomorphism, introduced by ,
is an isomorphism of commutative rings constructed in the theory of Lie algebras. The isomorphism maps the center of the universal enveloping algebra of a reductive Lie algebra to the elements of the symmetric algebra of a Cartan subalgebra that are invariant under the Weyl group .
Introduction and setting
Let be a semisimple Lie algebra, its Cartan subalgebra and be two elements of the weight space (where is the dual of ) and assume that a set of positive roots have been fixed. Let and be highest weight modules with highest weights and respectively.
Central characters
The -modules and are representations of the universal enveloping algebra and its center acts on the modules by scalar multiplication (this follows from the fact that the modules are generated by a highest weight vector). So, for and ,
and similarly for , where the functions are homomorphisms from to scalars called central characters.
Statement of Harish-Chandra theorem
For any , the characters if and only if and are on the same orbit of the Weyl group of , where is the half-sum of the positive roots, sometimes known as the Weyl vector.
Another closely related formulation is that the Harish-Chandra homomorphism from the center of the universal enveloping algebra to (the elements of the symmetric algebra of the Cartan subalgebra fixed by the Weyl group) is an isomorphism.
Explicit isomorphism
More explicitly, the isomorphism can be constructed as the composition of two maps, one from to and another from to itself.
The first is a projection . For a choice of positive roots , defining
as the corresponding positive nilpotent subalgebra and negative nilpotent subalgebra respectively, due to the Poincaré–Birkhoff–Witt theorem there is a decomposition
If is central, then in fact
The restriction of the projection to the centre is , and is a homomorphism of algebras. This is related to the central chara
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https://en.wikipedia.org/wiki/Differential%20variational%20inequality
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In mathematics, a differential variational inequality (DVI) is a dynamical system that incorporates ordinary differential equations and variational inequalities or complementarity problems.
DVIs are useful for representing models involving both dynamics and inequality constraints. Examples of such problems include, for example, mechanical impact problems, electrical circuits with ideal diodes, Coulomb friction problems for contacting bodies, and dynamic economic and related problems such as dynamic traffic networks and networks of queues (where the constraints can either be upper limits on queue length or that the queue length cannot become negative). DVIs are related to a number of other concepts including differential inclusions, projected dynamical systems, evolutionary inequalities, and parabolic variational inequalities.
Differential variational inequalities were first formally introduced by Pang and Stewart, whose definition should not be confused with the differential variational inequality used in Aubin and Cellina (1984).
Differential variational inequalities have the form to find such that
for every and almost all t; K a closed convex set, where
Closely associated with DVIs are dynamic/differential complementarity problems: if K is a closed convex cone, then the variational inequality is equivalent to the complementarity problem:
Examples
Mechanical Contact
Consider a rigid ball of radius falling from a height towards a table. Assume that the forces acting on the ball are gravitation and the contact forces of the table preventing penetration. Then the differential equation describing the motion is
where is the mass of the ball and is the contact force of the table, and is the gravitational acceleration. Note that both and are a priori unknown. While the ball and the table are separated, there is no contact force. There cannot be penetration (for a rigid ball and a rigid table), so for all . If then . On the other hand,
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https://en.wikipedia.org/wiki/Sonchus%20asper
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Sonchus asper, the prickly sow-thistle, rough milk thistle, spiny sowthistle, sharp-fringed sow thistle, or spiny-leaved sow thistle, is a widespread flowering plant in the tribe Cichorieae within the family Asteraceae.
Description
Sonchus asper is an annual or biennial herb sometimes reaching a height of with spiny leaves and yellow flowers resembling those of the dandelion. The leaves are bluish-green, simple, lanceolate, with wavy and sometimes lobed margins, covered in spines on both the margins and beneath. The base of the leaf surrounds the stem. The leaves and stems emit a milky sap when cut. One plant will produce several flat-topped arrays of flower heads, each head containing numerous yellow ray flowers but no disc flowers.
Distribution
Sonchus asper is native to Europe, North Africa, and western Asia. It has also become naturalized on other continents and is regarded as a noxious, invasive weed in many places. Its edible leaves make a palatable and nutritious leaf vegetable.
It is found in cultivated soil, pastures, roadsides, edges of yards, vacant lots, construction sites, waste areas and in grasslands.
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https://en.wikipedia.org/wiki/Lithoautotroph
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A lithoautotroph is an organism which derives energy from reactions of reduced compounds of mineral (inorganic) origin. Two types of lithoautotrophs are distinguished by their energy source; photolithoautotrophs derive their energy from light while chemolithoautotrophs (chemolithotrophs or chemoautotrophs) derive their energy from chemical reactions. Chemolithoautotrophs are exclusively microbes. Photolithoautotrophs include macroflora such as plants; these do not possess the ability to use mineral sources of reduced compounds for energy. Most chemolithoautotrophs belong to the domain Bacteria, while some belong to the domain Archaea. Lithoautotrophic bacteria can only use inorganic molecules as substrates in their energy-releasing reactions. The term "lithotroph" is from Greek lithos (λίθος) meaning "rock" and trōphos (τροφοσ) meaning "consumer"; literally, it may be read "eaters of rock". The "lithotroph" part of the name refers to the fact that these organisms use inorganic elements/compounds as their electron source, while the "autotroph" part of the name refers to their carbon source being CO2. Many lithoautotrophs are extremophiles, but this is not universally so, and some can be found to be the cause of acid mine drainage.
Lithoautotrophs are extremely specific in their source of reduced compounds. Thus, despite the diversity in using inorganic compounds that lithoautotrophs exhibit as a group, one particular lithoautotroph would use only one type of inorganic molecule to get its energy. A chemolithotrophic example are Anaerobic Ammonia Oxidizing Bacteria (ANAMMOX), which use ammonia and nitrite to produce N2. Additionally, in July 2020, researchers reported the discovery of chemolithoautotrophic bacterial cultures that feed on the metal manganese after performing unrelated experiments and named its bacterial species Candidatus Manganitrophus noduliformans and Ramlibacter lithotrophicus.
Metabolism
Some chemolithotrophs use redox half-reactions with low re
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https://en.wikipedia.org/wiki/Midas%20XL8
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The Midas XL8 was the first digital mixing console produced by Midas, previously a leading manufacturer of analogue mixing consoles for live sound. The introduction of the console came after years of digital console competition by Yamaha, Digidesign, and DiGiCo.
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https://en.wikipedia.org/wiki/Comparison%20of%20file%20systems
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The following tables compare general and technical information for a number of file systems.
General information
Metadata
Features
File capabilities
Block capabilities
Note that in addition to the below table, block capabilities can be implemented below the file system layer in Linux (LVM, , cryptsetup) or Windows (Volume Shadow Copy Service, SECURITY), etc.
Resize capabilities
"online" and "offline" are synonymous with "mounted" and "not mounted".
Allocation and layout policies
OS support
Limits
While storage devices usually have their size expressed in powers of 10 (for instance a 1 TB Solid State Drive will contain at least 1,000,000,000,000 (1012, 10004) bytes), filesystem limits are invariably powers of 2, so usually expressed with IEC prefixes. For instance, a 1 TiB limit means 240, 10244 bytes. Approximations (rounding down) using power of 10 are also given below to clarify.
See also
List of file systems
Comparison of file archivers
List of archive formats
Comparison of archive formats
Notes
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https://en.wikipedia.org/wiki/Michael%20Fourman
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Michael Paul Fourman FBCS FRSE (born 12 September 1950) is Professor of Computer Systems at the University of Edinburgh in Scotland, UK, and was Head of the School of Informatics from 2001 to 2009.
Fourman is worked in applications of logic in computer science, artificial intelligence, and cognitive science – more specifically, formal models of digital systems, system design tools, proof assistants, categorical semantics and propositional planning.
Qualifications
Fourman received a BSc in Mathematics and Philosophy from the University of Bristol in 1971, then his MSc in Mathematical Logic from the University of Oxford in 1972. He wrote his DPhil thesis Connections between Category Theory and Logic under the supervision of Dana Scott at Oxford, defending his thesis in 1974.
Career
He continued to work with Scott as an SRC postdoctoral Research Fellow and Junior Research Fellow of Wolfson College, in Oxford, until 1976, when he moved to the USA, first as a Visiting Assistant Professor of Mathematics at Clark University in Worcester, Massachusetts, then, from 1977 to 1982, as JF Ritt Assistant Professor of Mathematics at Columbia University in New York.
In 1983 he moved, with a Science and Engineering Research Council Fellowship, to the Department of Electronic and Electrical Engineering at Brunel University. He was appointed to a Readership, and then to the Chair of Formal Systems, at Brunel in 1986.
Fourman was co-founder and Technical Director of Abstract Hardware Limited (AHL), a company formed in 1986. He was central in the development of the LAMBDA system (Logic And Mathematics Behind Design Automation) to aid hardware design, a tool implemented in the SML programming language and marketed by AHL. He left the company in 1997.
In 1988 he joined the Laboratory for Foundations of Computer Science at the University of Edinburgh, and was appointed to the Chair of Computer Systems in the Department of Computer Science.
In 1998 he was founding Head of the Divisi
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https://en.wikipedia.org/wiki/Hypoglycin%20A
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Hypoglycin A is a naturally occurring amino acid derivative found in the unripened fruit of the Ackee tree (Blighia sapida) and in the seeds of the box elder tree (Acer negundo). It is toxic if ingested, and is the causative agent of Jamaican vomiting sickness. A 2017 Lancet report established a link between the consumption of unripened lychees (containing hypoglycin A or methylenecyclopropylglycine (MCPG)) resulting in hypoglycaemia and death from acute toxic encephalopathy.
Sources
The entirety of the unripe Ackee fruit is toxic and contains large amounts of hypoglycin. The fruit is safe to eat only when the fruit is allowed to fully open and expose the large black seeds while on the tree. The levels of the toxin decrease over time though from approximately 1000 ppm to around 0.1 ppm in the mature fruit.
Relatives of Ackee, including lychee, longan, and rambutan, can contain enough α-(methylenecyclopropyl)glycine, a homologue of hypoglycin A, in their fruit to cause hypoglycemic encephalopathy in undernourished children, when consumed in large quantities.
Toxicity
Hypoglycin A is a protoxin, meaning that the molecule is not toxic in itself but is broken down into toxic products when ingested. The branched-chain alpha-keto acid dehydrogenase complex, that normally converts leucine, isoleucine, or valine into acyl-CoA derivatives, converts Hypoglycin A into highly toxic MCPA-CoA. The FAD cofactor necessary for the beta oxidation of fatty acids associates with the alpha carbon of MCPA-CoA creating an irreversible complex that disables the enzyme. In addition, MCPA-CoA blocks some enzymes that are required for gluconeogenesis.
The reduction in gluconeogenesis and the reduction in fatty acid oxidation are thought to be the cause of most of the symptoms of Jamaican vomiting sickness. The blocking of fatty acid metabolism causes cells to start using glycogen for energy. Once glycogen is depleted, the body is unable to produce more, which leads to severe hypoglycem
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https://en.wikipedia.org/wiki/Supervisory%20circuit
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Supervisory circuits are electronic circuits that monitor one or more parameters of systems such as power supplies and microprocessors which must be maintained within certain limits, and take appropriate action if a parameter goes out of bounds, creating an unacceptable or dangerous situation.
Supervisory circuits are known by a variety of names, including battery monitors, power supply monitors, supply supervisory circuits, and reset circuits.
Thermal protection
A thermal protection circuit consists of a temperature-monitoring circuit and a control circuit. The control circuit may either shut down the circuitry it is protecting, reduce the power available in order to avoid overheating, or notify the system (software or user). These circuits may be quite complex, programmable and software-run, or simple with predefined limits.
Overvoltage and undervoltage protection
Voltage protection circuits protect circuitry from either overvoltage or undervoltage; either of these situations can have detrimental effects. Supervisory circuits that specifically focus on voltage regulation are often sold as supply voltage supervisors and will reset the protected circuit when the voltage returns to operating range.
Two types of overvoltage protection devices are currently used: clamping, which passes through voltages up to a certain level, and foldback, which shunts voltage away from the load. The shunting creates a short circuit which removes power from the protected circuitry. In certain applications this circuitry can reset itself after the dangerous condition has passed.
Fire Alarm Systems
Fire Alarm systems often supervise inputs and outputs with an end-of-line device such as a resistor or capacitor. The system looks for changes in resistance or capacitance values to determine if the circuit has an abnormal condition.
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https://en.wikipedia.org/wiki/Geographic%20Locator%20Codes
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Worldwide Geographic Location Codes (GLCs) list the number and letter codes federal agencies should use in designating geographic locations anywhere in the United States or abroad in computer programs. Use of standard codes facilitates the interchange of machine-readable data from agency to agency within the federal community and between federal offices and state and local groups. These codes are also used by some companies as a coding standard as well, especially those that must deal with federal, state and local governments for such things as taxes. The GLCs are administered by the U.S. General Services Administration (GSA).
External links
US General Services Administration site
General Services Administration
Geocodes
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https://en.wikipedia.org/wiki/Selective%20sweep
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In genetics, a selective sweep is the process through which a new beneficial mutation that increases its frequency and becomes fixed (i.e., reaches a frequency of 1) in the population leads to the reduction or elimination of genetic variation among nucleotide sequences that are near the mutation. In selective sweep, positive selection causes the new mutation to reach fixation so quickly that linked alleles can "hitchhike" and also become fixed.
Overview
A selective sweep can occur when a rare or previously non-existing allele that increases the fitness of the carrier (relative to other members of the population) increases rapidly in frequency due to natural selection. As the prevalence of such a beneficial allele increases, genetic variants that happen to be present on the genomic background (the DNA neighborhood) of the beneficial allele will also become more prevalent. This is called genetic hitchhiking. A selective sweep due to a strongly selected allele, which arose on a single genomic background, therefore results in a region of the genome with a large reduction of genetic variation in that chromosome region. The idea that strong positive selection could reduce nearby genetic variation due to hitchhiking was proposed by John Maynard-Smith and John Haigh in 1974.
Not all sweeps reduce genetic variation in the same way. Sweeps can be placed into three main categories:
The "classic selective sweep" or "hard selective sweep" is expected to occur when beneficial mutations are rare, but once a beneficial mutation has occurred it increases in frequency rapidly, thereby drastically reducing genetic variation in the population.
Another type of sweep, a "soft sweep from standing genetic variation," occurs when a previously neutral mutation that was present in a population becomes beneficial because of an environmental change. Such a mutation may be present on several genomic backgrounds so that when it rapidly increases in frequency, it doesn't erase all genetic v
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https://en.wikipedia.org/wiki/Coxeter%20graph
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In the mathematical field of graph theory, the Coxeter graph is a 3-regular graph with 28 vertices and 42 edges. It is one of the 13 known cubic distance-regular graphs. It is named after Harold Scott MacDonald Coxeter.
Properties
The Coxeter graph has chromatic number 3, chromatic index 3, radius 4, diameter 4 and girth 7. It is also a 3-vertex-connected graph and a 3-edge-connected graph. It has book thickness 3 and queue number 2.
The Coxeter graph is hypohamiltonian: it does not itself have a Hamiltonian cycle but every graph formed by removing a single vertex from it is Hamiltonian. It has rectilinear crossing number 11, and is the smallest cubic graph with that crossing number .
Construction
The simplest construction of a Coxeter graph is from a Fano plane. Take the 7C3 = 35 possible 3-combinations on 7 objects. Discard the 7 triplets that correspond to the lines of the Fano plane, leaving 28 triplets. Link two triplets if they are disjoint. The result is the Coxeter graph. (See image.) This construction exhibits the Coxeter graph as an induced subgraph of the odd graph O4, also known as the Kneser graph .
The Coxeter graph may also be constructed from the smaller distance-regular Heawood graph by constructing a vertex for each 6-cycle in the Heawood graph and an edge for each disjoint pair of 6-cycles.
The Coxeter graph may be derived from the Hoffman-Singleton graph. Take any vertex v in the Hoffman-Singleton graph. There is an independent set of size 15 that includes v. Delete the 7 neighbors of v, and the whole independent set including v, leaving behind the Coxeter graph.
Algebraic properties
The automorphism group of the Coxeter graph is a group of order 336. It acts transitively on the vertices, on the edges and on the arcs of the graph. Therefore, the Coxeter graph is a symmetric graph. It has automorphisms that take any vertex to any other vertex and any edge to any other edge. According to the Foster census, the Coxeter graph, referenced as F28
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https://en.wikipedia.org/wiki/List%20of%20paleoethnobotanists
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The following is a list of paleoethnobotanists.
Amy Bogaard
Gayle J. Fritz
Dorian Fuller
Christine A. Hastorf
Andreas G. Heiss
Hans Helbaek
Gordon Hillman
Maria Hopf
Stefanie Jacomet
Glynis Jones
Mordechai Kislev
Udelgard Körber-Grohne
Naomi F. Miller
Klaus Oeggl
Deborah M. Pearsall
Dolores Piperno
Jane Renfrew
Irwin Rovner
Marijke van der Veen
Willem van Zeist
George Willcox
Ulrich Willerding
Daniel Zohary
See also
List of plant scientists
Paleoethnobotany
External links
List of archaeobotanists at the Open Directory
Paleoethnobotanists
Paleoethnobotanist
Archaeobotanists
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https://en.wikipedia.org/wiki/Titanium%28III%29%20oxide
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Titanium(III) oxide is the inorganic compound with the formula Ti2O3. A black semiconducting solid, it is prepared by reducing titanium dioxide with titanium metal at 1600 °C.
Ti2O3 adopts the Al2O3 (corundum) structure. It is reactive with oxidising agents. At around 200 °C, there is a transition from semiconducting to metallic conducting. Titanium(III) oxide occurs naturally as the extremely rare mineral in the form of tistarite.
Other titanium(III) oxides include LiTi2O4 and LiTiO2.
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https://en.wikipedia.org/wiki/Tungsten%20disilicide
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Tungsten silicide (WSi2) is an inorganic compound, a silicide of tungsten. It is an electrically conductive ceramic material.
Chemistry
Tungsten silicide can react violently with substances such as strong acids, fluorine, oxidizers, and interhalogens.
Applications
It is used in microelectronics as a contact material, with resistivity 60–80 μΩ cm; it forms at 1000 °C. It is often used as a shunt over polysilicon lines to increase their conductivity and increase signal speed. Tungsten silicide layers can be prepared by chemical vapor deposition, e.g. using monosilane or dichlorosilane with tungsten hexafluoride as source gases. The deposited film is non-stoichiometric, and requires annealing to convert to more conductive stoichiometric form. Tungsten silicide is a replacement for earlier tungsten films. Tungsten silicide is also used as a barrier layer between silicon and other metals, e.g. tungsten.
Tungsten silicide is also of value towards use in microelectromechanical systems, where it is mostly applied as thin films for fabrication of microscale circuits. For such purposes, films of tungsten silicide can be plasma-etched using e.g. nitrogen trifluoride gas.
WSi2 performs well in applications as oxidation-resistant coatings. In particular, in similarity to Molybdenum disilicide, MoSi2, the high emissivity of tungsten disilicide makes this material attractive for high temperature radiative cooling, with implications in heat shields.
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https://en.wikipedia.org/wiki/Silversword%20alliance
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The silversword alliance, also known as the tarweeds, refers to an adaptive radiation of around 30 species in the composite or sunflower family, Asteraceae. The group is endemic to Hawaii, and is derived from a single immigrant to the islands. For radiating from a common ancestor at an estimated 5.2±0.8 Ma, the clade is extremely diverse, composed of trees, shrubs, subshrubs, mat-plants, cushion plants, rosette plants, and lianas.
The silversword alliance is named for its most famous and visually striking members, the silverswords. The species of the clade break down into three genera: Wilkesia, Argyroxiphium, and Dubautia. There are three species of silverswords and two greenswords in the genus Argyroxiphium, confined to the islands of Maui and Hawaii, and two species of Wilkesia (iliau) on Kauai. The bulk of the species are placed in the genus Dubautia, which is widespread on all the main islands.
The genus Dubautia contains a wide variety of forms, including cushion plants, shrubs, trees, and lianas.
Similar species frequently occur in the same habitat and are often difficult to tell apart. Hybrids frequently occur between Dubautia species, and between Dubautia and Argyroxiphium. As a result, there is some disagreement over the number of species, with modern sources giving between 28 and 33 species.
Characteristics
All members of the silversword alliance are perennials, but otherwise occupy a wide range of ecological niches.
Evolution
All Hawaiian tarweeds trace their lineage back to a species of Pacific coast tarweed, very similar to extant species like Carlquistia muirii. The last common ancestor of the silversword alliance was likely a mat and rhizome forming plant not more than tall, with a chromosome number of 2n = 16, and perhaps another similar species. Species of Dubautia however have 2n = 14 chromosomes. How the silverswords' chromosome number arose is a matter of some uncertainty, but two major scientific theories have been proposed. One is th
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https://en.wikipedia.org/wiki/Active%20queue%20management
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In routers and switches, active queue management (AQM) is the policy of dropping packets inside a buffer associated with a network interface controller (NIC) before that buffer becomes full, often with the goal of reducing network congestion or improving end-to-end latency. This task is performed by the network scheduler, which for this purpose uses various algorithms such as random early detection (RED), Explicit Congestion Notification (ECN), or controlled delay (CoDel). RFC 7567 recommends active queue management as a best practice.
Overview
An Internet router typically maintains a set of queues, one or more per interface, that hold packets scheduled to go out on that interface. Historically, such queues use a drop-tail discipline: a packet is put onto the queue if the queue is shorter than its maximum size (measured in packets or in bytes), and dropped otherwise.
Active queue disciplines drop or mark packets before the queue is full. Typically, they operate by maintaining one or more drop/mark probabilities, and occasionally dropping or marking packets according to the probabilities before the queue is full.
Benefits
Drop-tail queues have a tendency to penalise bursty flows, and to cause global synchronisation between flows. By dropping packets probabilistically, AQM disciplines typically avoid both of these issues.
By providing endpoints with congestion indication before the queue is full, AQM disciplines are able to maintain a shorter queue length than drop-tail queues, which combats bufferbloat and reduces network latency.
Drawbacks
Early AQM disciplines (notably RED and SRED) require careful tuning of their parameters in order to provide good performance. These systems are not optimally behaved from a control theory perspective. Modern AQM disciplines (ARED, Blue, PI, CoDel, CAKE) are self-tuning, and can be run with their default parameters in most circumstances.
Network engineers have historically been trained to avoid packet loss, and have ther
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https://en.wikipedia.org/wiki/Leibniz%20formula%20for%20determinants
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In algebra, the Leibniz formula, named in honor of Gottfried Leibniz, expresses the determinant of a square matrix in terms of permutations of the matrix elements. If is an matrix, where is the entry in the -th row and -th column of , the formula is
where is the sign function of permutations in the permutation group , which returns and for even and odd permutations, respectively.
Another common notation used for the formula is in terms of the Levi-Civita symbol and makes use of the Einstein summation notation, where it becomes
which may be more familiar to physicists.
Directly evaluating the Leibniz formula from the definition requires operations in general—that is, a number of operations asymptotically proportional to factorial—because is the number of order- permutations. This is impractically difficult for even relatively small . Instead, the determinant can be evaluated in operations by forming the LU decomposition (typically via Gaussian elimination or similar methods), in which case and the determinants of the triangular matrices and are simply the products of their diagonal entries. (In practical applications of numerical linear algebra, however, explicit computation of the determinant is rarely required.) See, for example, . The determinant can also be evaluated in fewer than operations by reducing the problem to matrix multiplication, but most such algorithms are not practical.
Formal statement and proof
Theorem.
There exists exactly one function which is alternating multilinear w.r.t. columns and such that .
Proof.
Uniqueness: Let be such a function, and let be an matrix. Call the -th column of , i.e. , so that
Also, let denote the -th column vector of the identity matrix.
Now one writes each of the 's in terms of the , i.e.
.
As is multilinear, one has
From alternation it follows that any term with repeated indices is zero. The sum can therefore be restricted to tuples with non-repeating indices, i.e. permutation
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https://en.wikipedia.org/wiki/Kautsky%20effect
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In biophysics, the Kautsky effect (also fluorescence transient, fluorescence induction or fluorescence decay) is a phenomenon consisting of a typical variation in the behavior of a plant fluorescence when exposed to light. It was discovered in 1931 by H. Kautsky and A. Hirsch.
When dark-adapted photosynthesising cells are illuminated with continuous light, chlorophyll fluorescence displays characteristic changes in intensity accompanying the induction of photosynthetic activity.
Application of Kautsky effect
The quantum yield of photosynthesis, which is also the photochemical quenching of fluorescence, is calculated through the following equation:
Φp = (Fm-F0)/Fm = Fv/Fm
F0 is the low fluorescence intensity, which is measured by a short light flash that is not strong enough to cause photochemistry, and thus induces fluorescence. Fm is the maximum fluorescence that can be obtained from a sample by measuring the highest intensity of fluorescence after a saturating flash. The difference between the measured values is the variable fluorescence Fv.
Explanation
When a sample (leaf or algal suspension) is illuminated, the fluorescence intensity increases with a time constant in the microsecond or millisecond range. After a few seconds the intensity decreases and reaches a steady-state level. The initial rise of the fluorescence intensity is attributed to the progressive saturation of the reaction centers of photosystem 2 (PSII). Therefore, photochemical quenching increases with the time of illumination, with a corresponding increase of the fluorescence intensity. The slow decrease of the fluorescence intensity at later times is caused, in addition to other processes, by non-photochemical quenching. Non-photochemical quenching is a protection mechanism in photosynthetic organisms as they have to avoid the adverse effect of excess light. Which components contribute and in which quantities remains an active but controversial area of research. It is known that carotenoid
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https://en.wikipedia.org/wiki/FLEX%20%28satellite%29
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The FLuorescence EXplorer (FLEX) is a planned mission by the European Space Agency to launch a satellite to monitor the global steady-state chlorophyll fluorescence in terrestrial vegetation. FLEX was selected for funding on 19 November 2015 and will be launched on a Vega C rocket from Guiana Space Centre in mid-2025.
Overview
The FLuorescence EXplorer (FLEX) mission is the eighth mission in the Earth Explorer programme, (part of ESA's Living Planet Programme). It comprises a satellite for the global monitoring of steady-state chlorophyll fluorescence in terrestrial vegetation. Leaf photosynthesis releases energy not required in the biochemical process in the form of light in wavelength between 640 and 800 nanometres.
After more than 70 years of basic and applied research in chlorophyll fluorescence, it is now established that fluorescence is a sensitive indicator of photosynthesis in both healthy and physiologically perturbed vegetation that can be used to monitor croplands and forests.
Fluorescence is a powerful non-invasive tool to track the status, resilience, and recovery of photochemical processes, and provides important information on overall photosynthetic performance with implications for related carbon sequestration. The early responsiveness of fluorescence to atmospheric, soil and plant water balance, as well as to atmospheric chemistry and human intervention in land usage, makes it a useful biological indicator in improving the understanding of Earth system dynamics.
FLEX will encompass a three-instrument array for measurement of the interrelated features of fluorescence, hyperspectral reflectance, and canopy temperature.
The program will involve a space and ground-measurement program of 3-years duration and will provide data formats for research and applied science.
See also
Photosynthetic efficiency
Phototroph
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https://en.wikipedia.org/wiki/XLD%20agar
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Xylose Lysine Deoxycholate agar (XLD agar) is a selective growth medium used in the isolation of Salmonella and Shigella species from clinical samples and from food. The agar was developed by Welton Taylor in 1965. It has a pH of approximately 7.4, leaving it with a bright pink or red appearance due to the indicator phenol red. Sugar fermentation lowers the pH and the phenol red indicator registers this by changing to yellow. Most gut bacteria, including Salmonella, can ferment the sugar xylose to produce acid; Shigella colonies cannot do this and therefore remain red. After exhausting the xylose supply Salmonella colonies will decarboxylate lysine, increasing the pH once again to alkaline and mimicking the red Shigella colonies. Salmonellae metabolise thiosulfate to produce hydrogen sulfide, which leads to the formation of colonies with black centers and allows them to be differentiated from the similarly coloured Shigella colonies.
Other Enterobacteria such as E. coli will ferment the lactose present in the medium to an extent that will prevent pH reversion by decarboxylation and acidify the medium turning it yellow.
Salmonella species: red colonies, some with black centers. The agar itself will turn red due to the presence of Salmonella type colonies.
Shigella species: red colonies.
Coliforms: yellow to orange colonies.
Pseudomonas aeruginosa: pink, flat, rough colonies. This type of colony can be easily mistaken for Salmonella due to the color similarities.
XLD agar contains:
See also
Agar plate
MRS agar
R2a agar
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https://en.wikipedia.org/wiki/Selenite%20broth
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Selenite broth is used as a selective medium for the isolation of Salmonella species. Selenite broth was originated by Leifson, while observing good recovery of Salmonella spp. and reduced
growth of fecal coliforms. Selenite broth is used as a selective enrichment for the cultivation of Salmonella
spp. that may be present in small numbers and competing with intestinal flora. This medium must not be autoclaved. Once prepared, it is steamed at 100°C for 30 minutes. There should be a very slight red precipitate. To minimize the risk of teratogenicity to workers, sodium selenite must be added separately to the medium. It has a pH of approximately 7.1. Selenite broth gives pale or colorless colonies.
Selenite broth contains:
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https://en.wikipedia.org/wiki/Rappaport%20Vassiliadis%20soya%20peptone%20broth
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Rappaport-Vassiliadis soya peptone broth (RVS broth) is used as an enrichment growth medium for the isolation of Salmonella species. It is not recommended for the enrichment of Salmonella Typhi or Paratyphi, which is inhibited due to the malachite green in RVS broth. It is an alternative to selenite broth. It is not associated with potential teratogenicity problems seen with the use of selenite broth. It enriches salmonellae because they are better able to survive the high osmotic pressure in the medium and because they can multiply at relatively lower pH and higher temperatures compared with other gut bacteria. RVS broth has a pH around 5.2.
Components
A liter of RVS broth contains:
4.5g Soya peptone
7.2g Sodium chloride
1.26g Potassium dihydrogen phosphate
0.18g Dipotassium phosphate
13.58g Magnesium chloride (anhydrous)
0.036g Malachite green
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https://en.wikipedia.org/wiki/Arsenic%20contamination%20of%20groundwater
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Arsenic contamination of groundwater is a form of groundwater pollution which is often due to naturally occurring high concentrations of arsenic in deeper levels of groundwater. It is a high-profile problem due to the use of deep tube wells for water supply in the Ganges Delta, causing serious arsenic poisoning to large numbers of people. A 2007 study found that over 137 million people in more than 70 countries are probably affected by arsenic poisoning of drinking water. The problem became a serious health concern after mass poisoning of water in Bangladesh. Arsenic contamination of ground water is found in many countries throughout the world, including the US.
The World Health Organization recommends limiting arsenic concentrations in water to 10 μg/L, although this is often an unattainable goal for many problem areas due to the difficult nature of removing arsenic from water sources.
Approximately 20 major incidents of groundwater arsenic contamination have been reported. Of these, four major incidents occurred in Asia—in Bangladesh; West Bengal, India; Inner Mongolia, China; and Taiwan. Locations of potentially hazardous wells have been mapped in China.
Sources
Gold mining can contaminate groundwater with arsenic, because the element typically occurs in gold-containing ores. Gold processing releases arsenic from mine tailings, and contaminated groundwater may be unsafe to drink for decades. Arsenic that is naturally occurring can contaminate the soil, just as it does the groundwater. This presents a possible arsenic exposure for people who smoke products containing tobacco, because the tobacco plant grows from the soil and can become infiltrated with the arsenic.
Speciation of arsenic compounds in water
Arsenic contaminated water typically contains arsenous acid and arsenic acid or their derivatives. Their names as "acids" is a formality; these species are not aggressive acids but are merely the soluble forms of arsenic near neutral pH. These compounds ar
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https://en.wikipedia.org/wiki/Information%20diving
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Information diving is the practice of recovering technical data, sometimes confidential or secret, from discarded material. In recent times, this has chiefly been from data storage elements in discarded computers, most notably recoverable data remaining on hard drives. Those in charge of discarding computers usually neglect to erase the hard drive. It is often in such circumstances for an information diver to copy installed software (e.g., word processors, operating systems, computer games, etc.). Other data may also be available, such as credit card information that was stored on the machine. Companies claim to be especially careful with customer data, but the number of data breaches by any type of entity (e.g., education, health care, insurance, government, ...) suggest otherwise. In the UK, information diving has been referred to as "binology."
Today, files, letters, memos, photographs, IDs, passwords, credit cards, and more can be found in dumpsters. Many people do not consider that sensitive information on items they discarded may be recovered. Such information, when recovered, is sometimes usable for fraudulent purposes (see also "identity theft" and physical information security). This method of dumpster diving is also sometimes used by attorneys or their agents when seeking to enforce court-ordered money judgments: the judgment debtor's trash may contain information about assets that can then be more-readily located for levying.
Supposedly, information diving was more common in the 1980s due to lax security; when businesses became aware of the need for increased security in the early 1990s, sensitive documents were shredded before being placed in dumpsters. There is still considerable Internet activity on the subject of dumpster diving, so it is unlikely to have stopped with the widespread introduction of document shredding. Security mythology has it that curious hackers or malicious crackers commonly use this technique.
Cases
Printed manuals
In earlie
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https://en.wikipedia.org/wiki/Perron%20number
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In mathematics, a Perron number is an algebraic integer α which is real and exceeds 1, but such that its conjugate elements are all less than α in absolute value. For example, the larger of the two roots of the irreducible polynomial is a Perron number.
Perron numbers are named after Oskar Perron; the Perron–Frobenius theorem asserts that, for a real square matrix with positive algebraic coefficients whose largest eigenvalue is greater than one, this eigenvalue is a Perron number. As a closely related case, the Perron number of a graph is defined to be the spectral radius of its adjacency matrix.
Any Pisot number or Salem number is a Perron number, as is the Mahler measure of a monic integer polynomial.
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https://en.wikipedia.org/wiki/Clomazone
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Clomazone is an agricultural herbicide, and has been the active ingredient of products named "Command" and "Commence". The molecule consists of a 2-chlorobenzyl group bound to a N-O heterocycle called isoxazolidinone. It is a white solid.
Clomazone was first registered by the USEPA on March 8, 1993, and was commercialized by FMC Corporation. It is used for broadleaf weed control in several crops, including soybeans, peas, maize, oilseed rape, sugar cane, cassava, pumpkins and tobacco. It may be applied pre-emergence of incorporated before planting the crop. Clomazone is relatively volatile (vapor pressure is 19.2 mPa) and vapors induce striking visual symptoms on non-target sensitive plants. Clomazone undergoes biological degradation, exhibiting a soil half life of one to four months. Adsorption of the herbicide to soil solids slows degradation and volatilization. Encapsulation helps reduce volatility and therefore reduces off-target damage to sensitive plants.
Clomazone suppresses the biosynthesis of chlorophyll and other plant pigments.
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https://en.wikipedia.org/wiki/Volume%20boot%20record
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A volume boot record (VBR) (also known as a volume boot sector, a partition boot record or a partition boot sector) is a type of boot sector introduced by the IBM Personal Computer. It may be found on a partitioned data storage device, such as a hard disk, or an unpartitioned device, such as a floppy disk, and contains machine code for bootstrapping programs (usually, but not necessarily, operating systems) stored in other parts of the device. On non-partitioned storage devices, it is the first sector of the device. On partitioned devices, it is the first sector of an individual partition on the device, with the first sector of the entire device being a Master Boot Record (MBR) containing the partition table.
The code in volume boot records is invoked either directly by the machine's firmware or indirectly by code in the master boot record or a boot manager. Code in the MBR and VBR is in essence loaded the same way.
Invoking a VBR via a boot manager is known as chain loading. Some dual-boot systems, such as NTLDR (the boot loader for all releases of Microsoft's Windows NT-derived operating systems up to and including Windows XP and Windows Server 2003), take copies of the bootstrap code that individual operating systems install into a single partition's VBR and store them in disc files, loading the relevant VBR content from file after the boot loader has asked the user which operating system to bootstrap.
In Windows Vista, Windows Server 2008 and newer versions, NTLDR was replaced; the boot-loader functionality is instead provided by two new components: WINLOAD.EXE and the Windows Boot Manager.
In file systems such as FAT12 (except for in DOS 1.x), FAT16, FAT32, HPFS and NTFS, the VBR also contains a BIOS Parameter Block (BPB) that specifies the location and layout of the principal on-disk data structures for the file system. (A detailed discussion of the sector layout of FAT VBRs, the various FAT BPB versions and their entries can be found in the FAT article.)
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https://en.wikipedia.org/wiki/Hutchinson%27s%20triad
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Hutchinson's triad is named after Sir Jonathan Hutchinson (1828–1913). It is a common pattern of presentation for late congenital syphilis, and consists of three phenomena: interstitial keratitis, malformed teeth (Hutchinson incisors and mulberry molars), and eighth nerve deafness. There may also be a deformity on the nose known as saddle nose deformity.
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https://en.wikipedia.org/wiki/Kolliphor%20EL
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Kolliphor EL, formerly known as Cremophor EL, is the registered trademark of BASF Corp. for its version of polyethoxylated castor oil. It is prepared by reacting 35 moles of ethylene oxide with each mole of castor oil. The resulting product is a mixture (CAS number 61791-12-6): the major component is the material in which the hydroxyl groups of the castor oil triglyceride have ethoxylated with ethylene oxide to form polyethylene glycol ethers. Minor components are the polyethyelene glycol esters of ricinoleic acid, polyethyelene glycols and polyethyelene glycol ethers of glycerol. Kolliphor EL is a synthetic, nonionic surfactant used to stabilize emulsions of nonpolar materials in water.
Kolliphor EL is an excipient or additive in drugs. Therapeutically, modern drugs are rarely given in a pure chemical state, so most active ingredients are combined with excipients or additives such as Kolliphor EL.
Uses
Miconazole, anti-fungal
Paclitaxel (Taxol), anti-cancer
Aci-Jel (acetic acid / oxyquinoline / ricinoleic acid - vaginal)
Sandimmune (cyclosporine injection, USP)
Nelfinavir mesylate, HIV protease inhibitor
Propofol, intravenous anaesthetic agent, originally solublized with Cremophor EL in trials; later approved with a lipid emulsion
Diazepam injection; superseded by lipid emulsion alternative (Diazemuls)
Vitamin K injection
Ixabepilone, anti-cancer
Side effects
Allergic reactions to Taxol are most often allergic reactions to Kolliphor EL; symptoms include tightness in the chest, shortness of breath, and similar reactions consistent with severe anaphylactic reactions. Although many anti-allergens including corticosteroids and Benadryl may be administered before chemotherapy, they are not always sufficient to prevent the severe reaction to Kolliphor EL.
Allergic reaction should not be confused with the normal side effects of Taxol. The allergic reaction is usually immediate, similar to severe allergic reactions typical of other allergens.
BASF offers a
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https://en.wikipedia.org/wiki/Speech%20perception
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Speech perception is the process by which the sounds of language are heard, interpreted, and understood. The study of speech perception is closely linked to the fields of phonology and phonetics in linguistics and cognitive psychology and perception in psychology. Research in speech perception seeks to understand how human listeners recognize speech sounds and use this information to understand spoken language. Speech perception research has applications in building computer systems that can recognize speech, in improving speech recognition for hearing- and language-impaired listeners, and in foreign-language teaching.
The process of perceiving speech begins at the level of the sound signal and the process of audition. (For a complete description of the process of audition see Hearing.) After processing the initial auditory signal, speech sounds are further processed to extract acoustic cues and phonetic information. This speech information can then be used for higher-level language processes, such as word recognition.
Acoustic cues
Acoustic cues are sensory cues contained in the speech sound signal which are used in speech perception to differentiate speech sounds belonging to different phonetic categories. For example, one of the most studied cues in speech is voice onset time or VOT. VOT is a primary cue signaling the difference between voiced and voiceless plosives, such as "b" and "p". Other cues differentiate sounds that are produced at different places of articulation or manners of articulation. The speech system must also combine these cues to determine the category of a specific speech sound. This is often thought of in terms of abstract representations of phonemes. These representations can then be combined for use in word recognition and other language processes.
It is not easy to identify what acoustic cues listeners are sensitive to when perceiving a particular speech sound:
At first glance, the solution to the problem of how we perceive speech seem
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https://en.wikipedia.org/wiki/EFI%20system%20partition
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The EFI (Extensible Firmware Interface) system partition or ESP is a partition on a data storage device (usually a hard disk drive or solid-state drive) that is used by computers having the Unified Extensible Firmware Interface (UEFI). When a computer is booted, UEFI firmware loads files stored on the ESP to start installing operating systems and various utilities.
An ESP contains the boot loaders or kernel images for all installed operating systems (which are contained in other partitions), device driver files for hardware devices present in a computer and used by the firmware at boot time, system utility programs that are intended to be run before an operating system is booted, and data files such as error logs.
Overview
The EFI system partition is formatted with a file system whose specification is based on the FAT file system and maintained as part of the UEFI specification; therefore, the file system specification is independent from the original FAT specification. The actual extent of divergence is unknown: Apple maintains a separate tool that should be used, while other systems use FAT utilities just fine. The globally unique identifier (GUID) for the EFI system partition in the GUID Partition Table (GPT) scheme is , while its ID in the master boot record (MBR) partition-table scheme is . Both GPT- and MBR-partitioned disks can contain an EFI system partition, as UEFI firmware is required to support both partitioning schemes. Also, El Torito bootable format for CD-ROMs and DVDs is supported.
UEFI provides backward compatibility with legacy systems by reserving the first block (sector) of the partition for compatibility code, effectively creating a legacy boot sector. On legacy BIOS-based systems, the first sector of a partition is loaded into memory, and execution is transferred to this code. UEFI firmware does not execute the code in the MBR, except when booting in legacy BIOS mode through the Compatibility Support Module (CSM).
The UEFI specification
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https://en.wikipedia.org/wiki/Alan%20Kotok
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Alan Kotok (November 9, 1941 – May 26, 2006) was an American computer scientist known for his work at Digital Equipment Corporation (Digital, or DEC) and at the World Wide Web Consortium (W3C). Steven Levy, in his book Hackers: Heroes of the Computer Revolution, describes Kotok and his classmates at the Massachusetts Institute of Technology (MIT) as the first true hackers.
Kotok was a precocious child who skipped two grades before college. At MIT, he became a member of the Tech Model Railroad Club, and after enrolling in MIT's first freshman programming class, he helped develop some of the earliest computer software including a digital audio program and what is sometimes called the first video game (Spacewar!). Together with his teacher John McCarthy and other classmates, he was part of the team that wrote the Kotok-McCarthy program which took part in the first chess match between computers.
After leaving MIT, Kotok joined the computer manufacturer Digital Equipment Corporation (DEC), where he worked for over 30 years. He was the chief architect of the PDP-10 family of computers, and created the company's Internet Business Group, responsible for several forms of Web-based technology including the first popular search engine. Kotok is known for his contributions to the Internet and to the World Wide Web through his work at the World Wide Web Consortium, which he and Digital had helped to found, and where he served as associate chairman.
Personal life
Alan Kotok was born in Philadelphia, Pennsylvania, and was raised as an only child in Vineland, New Jersey. During his childhood, he played with tools in his father's hardware store and learned model railroading. He was a precocious child, skipping two grades at high school, and he matriculated at Massachusetts Institute of Technology (MIT) at the age of 16 in the fall of 1958 and an MBA from Clark University in 1978. Although his interest in computers began at Vineland High School, his first practical experience of c
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https://en.wikipedia.org/wiki/TrueNAS
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TrueNAS is the branding for a range of free and open-source network-attached storage (NAS) operating systems produced by iXsystems, and based on FreeBSD and Linux, using the OpenZFS file system. It is licensed under the terms of the BSD License and runs on commodity x86-64 hardware.
The TrueNAS range includes free public versions (TrueNAS CORE, previously known as FreeNAS), commercial versions (TrueNAS Enterprise), and Linux versions (TrueNAS SCALE). It also offers hardware, from small home systems to large petabyte arrays, based on the above versions.
TrueNAS supports Windows, macOS and Unix clients and various virtualization hosts such as XenServer and VMware using the SMB, AFP, NFS, iSCSI, SSH, rsync and FTP/TFTP protocols. Advanced TrueNAS features include full-disk encryption and a plug-in architecture for third-party software.
Products
TrueNAS is the brand for iXsystems' open source network attached storage platform. It includes the following:
TrueNAS CORE (previously FreeNAS) – a free file server and expandable platform based on FreeBSD.
TrueNAS Enterprise – an enterprise file server for commercial use, also based on FreeBSD.
TrueNAS SCALE – a free Linux based hyper-converged scale-out version of the TrueNAS platform.
TrueNAS hardware – Enterprise Storage Arrays, a network-attached storage (NAS) systems, storage area network (SAN) devices, and High Availability systems, with up to 22 petabytes raw capacity.
User experience
TrueNAS is managed through a comprehensive web interface that is supplemented by a minimal shell console that handles essential administrative functions. The web interface supports storage pool configuration, user management, sharing configuration and system maintenance. As an embedded system appliance, TrueNAS boots from a USB Flash device or SATA DOM. This image is configured using a USB Flash bootable installer. The TrueNAS operating system is fully independent of its storage disks, allowing its configuration database and encry
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https://en.wikipedia.org/wiki/AP%20Physics%20C%3A%20Mechanics
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Advanced Placement (AP) Physics C: Mechanics (also known as AP Mechanics) is an introductory physics course administered by the College Board as part of its Advanced Placement program. It is intended to proxy a one-semester calculus-based university course in mechanics. The content of Physics C: Mechanics overlaps with that of AP Physics 1, but Physics 1 is algebra-based, while Physics C is calculus-based. Physics C: Mechanics may be combined with its electricity and magnetism counterpart to form a year-long course that prepares for both exams.
Course content
Intended to be equivalent to an introductory college course in mechanics for physics or engineering majors, the course modules are:
Kinematics
Newton's laws of motion
Work, energy and power
Systems of particles and linear momentum
Circular motion and rotation
Oscillations and gravitation.
Methods of calculus are used wherever appropriate in formulating physical principles and in applying them to physical problems. Therefore, students should have completed or be concurrently enrolled in a Calculus I class.
This course is often compared to AP Physics 1: Algebra Based for its similar course material involving kinematics, work, motion, forces, rotation, and oscillations. However, AP Physics 1: Algebra Based lacks concepts found in Calculus I, like derivatives or integrals.
This course may be combined with AP Physics C: Electricity and Magnetism to make a unified Physics C course that prepares for both exams.
AP test
The course culminates in an optional exam for which high-performing students may receive some credit towards their college coursework, depending on the institution.
Registration
The AP examination for AP Physics C: Mechanics is separate from the AP examination for AP Physics C: Electricity and Magnetism. Before 2006, test-takers paid only once and were given the choice of taking either one or two parts of the Physics C test.
Format
The exam is typically administered on a Monday aftern
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https://en.wikipedia.org/wiki/Institute%20of%20Applied%20Physics%20and%20Computational%20Mathematics
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The Institute of Applied Physics and Computational Mathematics (IAPCM) was established in 1958 in Beijing in the People's Republic of China. The institution conducts research on nuclear warhead design computations for the Chinese Academy of Engineering Physics (CAEP) in Mianyang, Sichuan and focuses on applied theoretical research and on the study of fundamental theories. Its main research fields include: Theoretical physics, nuclear fusion, plasma physics, nuclear physics, atomic molecular physics, laser physics, fluid dynamics, applied mathematics, and arms control science and technology.
The Federal Bureau of Investigation has stated that IAPCM has targeted U.S. defense labs for industrial espionage.
From August 2012, the director of the institute was LI Hua.
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https://en.wikipedia.org/wiki/Deep%20cervical%20artery
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The deep cervical artery (Profunda cervicalis) is an artery of the neck.
Course
It arises, in most cases, from the costocervical trunk, and is analogous to the posterior branch of an aortic intercostal artery: occasionally it is a separate branch from the subclavian artery.
Passing backward, above the eighth cervical nerve and between the transverse process of the seventh cervical vertebra and the neck of the first rib, it runs up the back of the neck, between the semispinalis capitis and semispinalis cervicis, as high as the axis vertebra, supplying these and adjacent muscles, and anastomosing with the deep division of the descending branch of the occipital, and with branches of the vertebral.
It gives off a spinal twig which enters the canal through the intervertebral foramen between the seventh cervical and first thoracic vertebrae.
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https://en.wikipedia.org/wiki/Costocervical%20trunk
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The costocervical trunk arises from the upper and back part of the second part of subclavian artery, behind the scalenus anterior on the right side, and medial to that muscle on the left side.
Passing backward, it splits into the deep cervical artery and the supreme intercostal artery (highest intercostal artery), which descends behind the pleura in front of the necks of the first and second ribs, and anastomoses with the first aortic intercostal (3rd posterior intercostal artery).
As it crosses the neck of the first rib it lies medial to the anterior division of the first thoracic nerve, and lateral to the first thoracic ganglion of the sympathetic trunk.
In the first intercostal space, it gives off a branch which is distributed in a manner similar to the distribution of the aortic intercostals.
The branch for the second intercostal space usually joins with one from the highest aortic intercostal artery.
This branch is not constant, but is more commonly found on the right side; when absent, its place is supplied by an intercostal branch from the aorta.
Each intercostal gives off a posterior branch which goes to the posterior vertebral muscles, and sends a small spinal branch through the corresponding intervertebral foramen to the medulla spinalis and its membranes.
Branches
Deep cervical artery
supreme intercostal artery
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