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https://en.wikipedia.org/wiki/MIAT
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MIAT may refer to:
Mazda MX-5 Miata, a car
MIAT Mongolian Airlines
MIAT (museum), a textile and industry museum in Belgium
MIAT (gene), a long non-coding RNA gene
Miat may refer to :
an alternative name for the plant Memecylon edule
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https://en.wikipedia.org/wiki/Copper%20gluconate
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Copper gluconate is the copper salt of D-gluconic acid. It is an odorless light blue or blue-green crystal or powder which is easily soluble in water and insoluble in ethanol.
Uses
Dietary supplement to treat copper deficiency.
Ingredient of Retsyn, which is an ingredient of Certs breath mints.
Fertilizer deficiency corrector to treat lacks of this nutrient.
Side effects
The U.S. Institute of Medicine (IOM) sets tolerable upper intake levels (ULs) for vitamins and minerals when evidence is sufficient. In the case of copper the adult UL is set at 10 mg/day.
Copper gluconate is sold as a dietary supplement to provide copper. The typical dose is 2.0 mg copper per day. This is one-fifth what the IOM considers a safe upper limit. Long-term intake at amounts higher than the UL may cause liver damage.
References
External links
Copper gluconate monograph at Drugs.com
Copper(II) compounds
Dietary supplements
Coordination complexes
Gluconates
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https://en.wikipedia.org/wiki/Tverberg%27s%20theorem
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In discrete geometry, Tverberg's theorem, first stated by Helge Tverberg in 1966, is the result that sufficiently many points in d-dimensional Euclidean space can be partitioned into subsets with intersecting convex hulls. Specifically, for any positive integers d, r and any set of
points there exists a point x (not necessarily one of the given points) and a partition of the given points into r subsets, such that x belongs to the convex hull of all of the subsets. The partition resulting from this theorem is known as a Tverberg partition.
The special case r = 2 was proved earlier by Radon, and it is known as Radon's theorem.
Examples
The case d = 1 states that any 2r-1 points on the real line can be partitioned into r subsets with intersecting convex hulls. Indeed, if the points are x1 < x2 < ... < x2r < x2r-1, then the partition into Ai = {xi, x2r-i} for i in 1,...,r satisfies this condition (and it is unique).
For r = 2, Tverberg's theorem states that any d + 2 points may be partitioned into two subsets with intersecting convex hulls. This is known as Radon's theorem. In this case, for points in general position, the partition is unique.
The case r = 3 and d = 2 states that any seven points in the plane may be partitioned into three subsets with intersecting convex hulls. The illustration shows an example in which the seven points are the vertices of a regular heptagon. As the example shows, there may be many different Tverberg partitions of the same set of points; th
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https://en.wikipedia.org/wiki/Cartan%20formula
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In mathematics, Cartan formula can mean:
one in differential geometry: , where , and are Lie derivative, exterior derivative, and interior product, respectively, acting on differential forms. See interior product for the detail. It is also called the Cartan homotopy formula or Cartan magic formula. This formula is named after Élie Cartan.
one in algebraic topology, which is one of the five axioms of Steenrod algebra. It reads:
.
See Steenrod algebra for the detail. The name derives from Henri Cartan, son of Élie.
Footnotes
See also
List of things named after Élie Cartan
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https://en.wikipedia.org/wiki/List%20of%20textbooks%20in%20thermodynamics%20and%20statistical%20mechanics
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A list of notable textbooks in thermodynamics and statistical mechanics, arranged by category and date.
Only or mainly thermodynamics
Both thermodynamics and statistical mechanics
2e Kittel, Charles; and Kroemer, Herbert (1980) New York: W.H. Freeman
2e (1988) Chichester: Wiley , .
(1990) New York: Dover
Statistical mechanics
. 2e (1936) Cambridge: University Press; (1980) Cambridge University Press.
; (1979) New York: Dover
Vol. 5 of the Course of Theoretical Physics. 3e (1976) Translated by J.B. Sykes and M.J. Kearsley (1980) Oxford : Pergamon Press.
. 3e (1995) Oxford: Butterworth-Heinemann
. 2e (1987) New York: Wiley
. 2e (1988) Amsterdam: North-Holland . 2e (1991) Berlin: Springer Verlag ,
; (2005) New York: Dover
2e (2000) Sausalito, Calif.: University Science
2e (1998) Chichester: Wiley
Specialized topics
Kinetic theory
Vol. 10 of the Course of Theoretical Physics (3rd Ed). Translated by J.B. Sykes and R.N. Franklin (1981) London: Pergamon ,
Quantum statistical mechanics
Mathematics of statistical mechanics
Translated by G. Gamow (1949) New York: Dover
. Reissued (1974), (1989); (1999) Singapore: World Scientific
; (1984) Cambridge: University Press . 2e (2004) Cambridge: University Press
Miscellaneous
(available online here)
Historical
(1896, 1898) Translated by Stephen G. Brush (1964) Berkeley: University of California Press; (1995) New York: Dover
Translated by J. Kestin (1956) New York: Academic Press.
Germa
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https://en.wikipedia.org/wiki/Eta%20Leonis
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Eta Leonis (η Leo, η Leonis) is a fourth-magnitude star in the constellation Leo, about away.
Properties
Eta Leonis is a white supergiant with the stellar classification A0Ib. Since 1943, the spectrum of this star has served as one of the stable anchor points by which other stars are classified. Though its apparent magnitude is 3.5, making it a relatively dim star to the naked eye, it is nearly 20,000 times more luminous than the Sun, with an absolute magnitude of -5.60. The Hipparcos astrometric data has estimated the distance of Eta Leonis to be roughly 390 parsecs from Earth, or 1,270 light years away.
Eta Leonis is apparently a multiple star system, but the number of components and their separation is uncertain.
References
External links
Jim Kaler's Stars: Eta Leonis
Leo (constellation)
Leonis, Eta
A-type supergiants
BD+17 2171
Leonis, 30
3975
87737
049583
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https://en.wikipedia.org/wiki/Tensor%20fasciae%20latae%20muscle
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The tensor fasciae latae (or tensor fasciæ latæ or, formerly, tensor vaginae femoris) is a muscle of the thigh. Together with the gluteus maximus, it acts on the iliotibial band and is continuous with the iliotibial tract, which attaches to the tibia. The muscle assists in keeping the balance of the pelvis while standing, walking, or running.
Structure
It arises from the anterior part of the outer lip of the iliac crest; from the outer surface of the anterior superior iliac spine, and part of the outer border of the notch below it, between the gluteus medius and sartorius; and from the deep surface of the fascia lata.
It is inserted between the two layers of the iliotibial tract of the fascia lata about the junction of the middle and upper thirds of the thigh. The tensor fasciae latae tautens the iliotibial tract and braces the knee, especially when the opposite foot is lifted. The terminal insertion point lies on the lateral condyle of the tibia.
Nerve supply
Tensor fasciae latae is innervated by the superior gluteal nerve, L5 and S1. At its origins of the anterior rami of L4, L5, and S1 nerves, the superior gluteal nerve exits the pelvis via greater sciatic foramen superior to the piriformis. The nerve also courses between the gluteus medius and minimus. The superior gluteal artery also supplies the tensor fasciae latae. The superior gluteal nerve arises from the sacral plexus and only has muscular innervation associated with it. There is no cutaneous innervation for
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https://en.wikipedia.org/wiki/Extensor%20hallucis%20brevis%20muscle
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The extensor hallucis brevis is a muscle on the top of the foot that helps to extend the big toe.
Structure
The extensor hallucis brevis is essentially the medial part of the extensor digitorum brevis muscle. Some anatomists have debated whether these two muscles are distinct entities.
The extensor hallucis brevis arises from the calcaneus and inserts on the proximal phalanx of the digit 1 (the big toe).
Nerve supply
Nerve supplied by lateral terminal branch of Deep Peroneal Nerve (deep fibular nerve) (proximal sciatic branches S1, S2). Same innervation of Extensor Digitorum Brevis
Function
The extensor hallucis brevis helps to extend the big toe.
See also
Extensor digitorum brevis
Extensor hallucis longus
Additional Images
External links
- "Dorsum of the foot showing the tendons that cross the ankle joint."
Calf muscles
Muscles of the lower limb
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https://en.wikipedia.org/wiki/Arachnoid%20cyst
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Arachnoid cysts are cerebrospinal fluid covered by arachnoidal cells and collagen that may develop between the surface of the brain and the cranial base or on the arachnoid membrane, one of the three meningeal layers that cover the brain and the spinal cord. Primary arachnoid cysts are a congenital disorder whereas secondary arachnoid cysts are the result of head injury or trauma. Most cases of primary cysts begin during infancy; however, onset may be delayed until adolescence.
Signs and symptoms
Patients with arachnoid cysts may never show symptoms, even in some cases where the cyst is large. Therefore, while the presence of symptoms may provoke further clinical investigation, symptoms independent of further data cannot—and should not—be interpreted as evidence of a cyst's existence, size, location, or potential functional impact on the patient.
Symptoms vary by the size and location of the cyst(s), though small cysts usually have no symptoms and are discovered only incidentally. On the other hand, a number of symptoms may result from large cysts:
Cranial deformation or macrocephaly (enlargement of the head), particularly in children
Cysts in the suprasellar region in children have presented as bobbing and nodding of the head called bobble-head doll syndrome.
Cysts in the left middle cranial fossa have been associated with ADHD in a study on affected children.
Headaches. A patient experiencing a headache does not necessarily have an arachnoid cyst.
In a 2002 study in
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https://en.wikipedia.org/wiki/Open-access%20poll
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An open-access poll is a type of opinion poll in which a nonprobability sample of participants self-select into participation. The term includes call-in, mail-in, and some online polls.
The most common examples of open-access polls ask people to phone a number, click a voting option on a website, or return a coupon cut from a newspaper. By contrast, professional polling companies use a variety of techniques to attempt to ensure that the polls they conduct are representative, reliable and scientific. The most glaring difference between an open-access poll and a scientific poll is that scientific polls typically randomly select their samples and sometimes use statistical weights to make them representative of the target population.
Advantages and disadvantages
Since participants in an open-access poll are volunteers rather than a random sample, such polls represent the most interested individuals, just as in voting. In the case of political polls, such participants might be more likely voters.
Because no sampling frame is used to draw the sample of participants, open-access polls may not have participants that represent the larger population. Indeed, they may be composed simply of individuals who happen to hear about the poll. As a consequence, the results of the poll cannot be generalized, but are only representative of the participants of the poll.
One example of an error produced by an open access-poll was one taken by The Literary Digest to predict the 1936 United Sta
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https://en.wikipedia.org/wiki/Wetted%20area
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In fluid dynamics, the wetted area is the surface area that interacts with the working fluid or gas.
In maritime use, the wetted area is the area of the watercrafts hull which is immersed in water. This has a direct relationship on the overall hydrodynamic drag of the ship or submarine.
In aeronautics, the wetted area is the area which is in contact with the external airflow. This has a direct relationship on the overall aerodynamic drag of the aircraft. See also: Wetted aspect ratio.
In motorsport, such as Formula One, the term wetted surfaces is used to refer to the bodywork, wings and the radiator, which are in direct contact with the airflow, similarly to the term's use in aeronautics.
References
Intake Aerodynamics (October 1999) by Seddon and Goldsmith, Blackwell Science and the AIAA Educational Series; 2nd edition
Naval architecture
Aerodynamics
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https://en.wikipedia.org/wiki/Sample%20exclusion%20dimension
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In computational learning theory, sample exclusion dimensions arise in the study of exact concept learning with queries.
In algorithmic learning theory, a concept over a domain X is a Boolean function over X. Here we only consider finite domains. A partial approximation S of a concept c is a Boolean function over such that c is an extension to S.
Let C be a class of concepts and c be a concept (not necessarily in C). Then a specifying set for c w.r.t. C, denoted by S is a partial approximation S of c such that C contains at most one extension to S. If we have observed a specifying set for some concept w.r.t. C, then we have enough information to verify a concept in C with at most one more mind change.
The exclusion dimension, denoted by XD(C), of a concept class is the maximum of the size of the minimum specifying set of c' with respect to C, where c' is a concept not in C.
References
Computational learning theory
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https://en.wikipedia.org/wiki/Evolver%20%28software%29
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Evolver is a software package that allows users to solve a wide variety of optimization problems using a genetic algorithm. Launched in 1989, it was the first commercially available genetic algorithm package for personal computers, and is part of the permanent collection at the Computer History Museum. The program was originally developed by Matthew Jensen at Axcelis, Inc., and updated by Ayanna Howard. Evolver was acquired by Palisade Corporation, who continues to upgrade and sell the software to this day.
External links
Evolver official page
Axcelis, Inc. New York Times Article
Genetic algorithms
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https://en.wikipedia.org/wiki/Eosinophiluria
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Eosinophiluria is the abnormal presence of eosinophils in the urine. It can be measured by detecting levels of eosinophil cationic protein.
Associated conditions
It can be associated with a wide variety of conditions, including:
Kidney disorders such as acute interstitial nephritis and acute kidney injury from cholesterol embolism
Urinary tract infection
Eosinophilic granulomatosis with polyangiitis
Eosinophiluria (>5% of urine leukocytes ) is a common finding (~90%) in antibiotic induced allergic nephritis, however lymphocytes predominate in allergic interstitial nephritis induced by NSAIDs. Eosinophiluria is a feature of atheroembolic ARF.
In PAN, microscopic polyangitis, eosinophiluria is rare.
References
External links
Clinical correlates of eosinophiluria
Abnormal clinical and laboratory findings for urine
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https://en.wikipedia.org/wiki/Marching%20squares
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In computer graphics, marching squares is an algorithm that generates contours for a two-dimensional scalar field (rectangular array of individual numerical values). A similar method can be used to contour 2D triangle meshes.
The contours can be of two kinds:
Isolines – lines following a single data level, or isovalue.
Isobands – filled areas between isolines.
Typical applications include the contour lines on topographic maps or the generation of isobars for weather maps.
Marching squares takes a similar approach to the 3D marching cubes algorithm:
Process each cell in the grid independently.
Calculate a cell index using comparisons of the contour level(s) with the data values at the cell corners.
Use a pre-built lookup table, keyed on the cell index, to describe the output geometry for the cell.
Apply linear interpolation along the boundaries of the cell to calculate the exact contour position.
Basic algorithm
Here are the steps of the algorithm:
Apply a threshold to the 2D field to make a binary image containing:
1 where the data value is above the isovalue
0 where the data value is below the isovalue
Every 2x2 block of pixels in the binary image forms a contouring cell, so the whole image is represented by a grid of such cells (shown in green in the picture below). Note that this contouring grid is one cell smaller in each direction than the original 2D field.
For each cell in the contouring grid:
Compose the 4 bits at the corners of the cell to build a bi
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https://en.wikipedia.org/wiki/Norm%20Macdonald
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Norman Gene Macdonald (October 17, 1959September 14, 2021) was a Canadian stand-up comedian, actor, and writer whose style was characterized by deadpan delivery and the use of folksy, old-fashioned turns of phrase. He appeared in many films and was a regular guest on late-night talk shows, where he became known for his chaotic, yet understated style of comedy. Many critics and fellow comedians considered him to be the ultimate talk show guest, while prominent late-night figure David Letterman regarded him as "the best" of stand-up comedians.
Earlier in his career, Macdonald's first work on television included writing for such comedies as Roseanne and The Dennis Miller Show. In 1993, Macdonald was hired as a writer and cast member on Saturday Night Live (SNL), spending a total of five seasons on the series, which included anchoring the show's Weekend Update segment for three and a half seasons. He was removed as host of SNLs Weekend Update in 1998, allegedly for relentlessly mocking O. J. Simpson during his murder trial, offending producer Don Ohlmeyer who was a close friend of Simpson. After being fired from SNL, he wrote and starred in the 1998 film Dirty Work and headlined his own sitcom The Norm Show from 1999 to 2001. Macdonald was also a voice actor, and provided voice acting roles for Family Guy, The Fairly OddParents, Mike Tyson Mysteries, The Orville, and the Dr. Dolittle films.
Between 2013 and 2018, Macdonald hosted the talk shows Norm Macdonald Live (a video podc
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https://en.wikipedia.org/wiki/Curium%28III%29%20oxide
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Curium(III) oxide is a compound composed of curium and oxygen with the chemical formula . It is a crystalline solid with a unit cell that contains two curium atoms and three oxygen atoms. The simplest synthesis equation involves the reaction of curium(III) metal with O2−: 2 Cm3+ + 3 O2− ---> Cm2O3. Curium trioxide can exist as five polymorphic forms. Two of the forms exist at extremely high temperatures, making it difficult for experimental studies to be done on the formation of their structures. The three other possible forms which curium sesquioxide can take are the body-centered cubic form, the monoclinic form, and the hexagonal form. Curium(III) oxide is either white or light tan in color and, while insoluble in water, is soluble in inorganic and mineral acids. Its synthesis was first recognized in 1955.
Synthesis
Curium sesquioxide can be prepared in a variety of ways. (Note: Keep in mind that the ways listed below do not contain all of the possible ways in which it can be produced.)
Ignition with O2: Curium(III) oxalate is precipitated through a capillary tube. The precipitate is ignited by gaseous oxygen at 400 °C, and the resulting product is thermally decomposed via 600 °C and 10−4 mm of pressure.
Aerosolized Curium Sesquioxide: The aerosolization process of Cm2O3 can be done through multiple experimental processes. Typically, Cm2O3 is aerosolized for experimental procedures which set out to discover the effects of curium metal within a biological system.
Rout
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https://en.wikipedia.org/wiki/Chemotherapy%20regimen
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A chemotherapy regimen is a regimen for chemotherapy, defining the drugs to be used, their dosage, the frequency and duration of treatments, and other considerations. In modern oncology, many regimens combine several chemotherapy drugs in combination chemotherapy. The majority of drugs used in cancer chemotherapy are cytostatic, many via cytotoxicity.
A fundamental philosophy of medical oncology, including combination chemotherapy, is that different drugs work through different mechanisms, and that the results of using multiple drugs will be synergistic to some extent. Because they have different dose-limiting adverse effects, they can be given together at full doses in chemotherapy regimens.
The first successful combination chemotherapy was MOPP, introduced in 1963 for lymphomas.
The term "induction regimen" refers to a chemotherapy regimen used for the initial treatment of a disease. A "maintenance regimen" refers to the ongoing use of chemotherapy to reduce the chances of a cancer recurring or to prevent an existing cancer from continuing to grow.
Nomenclature
Chemotherapy regimens are often identified by acronyms, identifying the agents used in the drug combination. However, the letters used are not consistent across regimens, and in some cases - for example, "BEACOPP" - the same letter combination is used to represent two different treatments.
There is no widely accepted naming convention or standard for the nomenclature of chemotherapy regimens. For example, either
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https://en.wikipedia.org/wiki/Sulbactam
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Sulbactam is a β-lactamase inhibitor. This drug is given in combination with β-lactam antibiotics to inhibit β-lactamase, an enzyme produced by bacteria that destroys the antibiotics.
It was patented in 1977 and approved for medical use in 1986.
Medical uses
The combination ampicillin/sulbactam (Unasyn) is available in the United States.
The combination cefoperazone/sulbactam (Sulperazon) is available in many countries.
The co-packaged combination sulbactam/durlobactam was approved for medical use in the United States in May 2023.
Mechanism
Sulbactam is primarily used as a suicide inhibitor of β-lactamase, shielding more potent beta-lactams such as ampicillin. Sulbactam itself contains a beta-lactam ring, and has weak antibacterial activity by inhibiting penicillin binding proteins (PBP) 1 and 3, but not 2.
References
Further reading
Beta-lactamase inhibitors
Lactams
Sulfones
Carboxylic acids
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https://en.wikipedia.org/wiki/Peetre%20theorem
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In mathematics, the (linear) Peetre theorem, named after Jaak Peetre, is a result of functional analysis that gives a characterisation of differential operators in terms of their effect on generalized function spaces, and without mentioning differentiation in explicit terms. The Peetre theorem is an example of a finite order theorem in which a function or a functor, defined in a very general way, can in fact be shown to be a polynomial because of some extraneous condition or symmetry imposed upon it.
This article treats two forms of the Peetre theorem. The first is the original version which, although quite useful in its own right, is actually too general for most applications.
The original Peetre theorem
Let M be a smooth manifold and let E and F be two vector bundles on M. Let
be the spaces of smooth sections of E and F. An operator
is a morphism of sheaves which is linear on sections such that the support of D is non-increasing: supp Ds ⊆ supp s for every smooth section s of E. The original Peetre theorem asserts that, for every point p in M, there is a neighborhood U of p and an integer k (depending on U) such that D is a differential operator of order k over U. This means that D factors through a linear mapping iD from the k-jet of sections of E into the space of smooth sections of F:
where
is the k-jet operator and
is a linear mapping of vector bundles.
Proof
The problem is invariant under local diffeomorphism, so it is sufficient to prove it when M is
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https://en.wikipedia.org/wiki/Transverter
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In radio engineering, a transverter is a radio frequency device that consists of an upconverter and a downconverter in one unit. Transverters are used in conjunction with transceivers to change the range of frequencies over which the transceiver can communicate.
In electrical power engineering, a transverter is a universal electrical power converter that can combine, convert, analyze and control any combinations of DC or AC power.
Amateur radio use
Although not as convenient as a wide-range radio, amateurs who have invested a great deal of money or time in a fine-quality radio may find it more economical to extend the radio's range when new bands come available, rather than replace it. Some transceiver manufacturers are supportive of add-on transverters, and design in circuitry and cabling attachments for them.
High band use
Transverters are most commonly used in amateur radio to convert radio transceivers designed for use on the HF or VHF bands to operate on even higher frequency (microwave) bands. A transceiver used in this fashion is referred to as an IF radio, indicating that it connects into the "intermediate frequency" electronics in the chain of transceiver stages.
Common transceiver/transverter combinations include transverters for 50 MHz, 70 MHz, 144 MHz, 222 MHz, and 432 MHz designed for use with 28 MHz IF radios, and transverters for 50 MHz, 902 MHz, 1296 MHz, 2304 MHz, 3456 MHz, 5706 MHz, and 10368 MHz designed for use with 144 MHz IF radios. Some transverter
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https://en.wikipedia.org/wiki/Fagin%27s%20theorem
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Fagin's theorem is the oldest result of descriptive complexity theory, a branch of computational complexity theory that characterizes complexity classes in terms of logic-based descriptions of their problems rather than by the behavior of algorithms for solving those problems.
The theorem states that the set of all properties expressible in existential second-order logic is precisely the complexity class NP.
It was proven by Ronald Fagin in 1973 in his doctoral thesis, and appears in his 1974 paper. The arity required by the second-order formula was improved (in one direction) in , and several results of Grandjean have provided tighter bounds on nondeterministic random-access machines.
Proof
In addition to Fagin's 1974 paper, provides a detailed proof of the theorem. It is straightforward to show that every existential second-order formula can be recognized in NP, by nondeterministically choosing the value of all existentially-qualified variables, so the main part of the proof is to show that every language in NP can be described by an existential second-order formula. To do so, one can use second-order existential quantifiers to arbitrarily choose a computation tableau. In more detail, for every timestep of an execution trace of a non-deterministic Turing machine, this tableau encodes the state of the Turing machine, its position in the tape, the contents of every tape cell, and which nondeterministic choice the machine makes at that step. A first-order formula can c
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https://en.wikipedia.org/wiki/Schnyder%27s%20theorem
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In graph theory, Schnyder's theorem is a characterization of planar graphs in terms
of the order dimension of their incidence posets. It is named after Walter Schnyder, who published its proof in 1989.
The incidence poset of an undirected graph with vertex set and edge set is the partially ordered set of height 2 that has as its elements. In this partial order, there is an order relation when is a vertex, is an edge, and is one of the two endpoints of .
The order dimension of a partial order is the smallest number of total orderings whose intersection is the given partial order; such a set of orderings is called a realizer of the partial order.
Schnyder's theorem states that a graph is planar if and only if the order dimension of is at most three.
Extensions
This theorem has been generalized by to a tight bound on the dimension of the height-three partially ordered sets formed analogously from the vertices, edges and faces of a convex polyhedron, or more generally of an embedded planar graph: in both cases, the order dimension of the poset is at most four. However, this result cannot be generalized to higher-dimensional convex polytopes, as there exist four-dimensional polytopes whose face lattices have unbounded order dimension.
Even more generally, for abstract simplicial complexes, the order dimension of the face poset of the complex is at most , where is the minimum dimension of a Euclidean space in which the complex has a geometric realization .
Other
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https://en.wikipedia.org/wiki/Jan%20Mauersberger
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Jan Mauersberger (born 17 June 1985) is a retired German footballer who played as a defender.
Mauersberger retired at the end of the 2018/19 season.
Career statistics
References
External links
1985 births
Living people
German men's footballers
Germany men's youth international footballers
FC Bayern Munich II players
SpVgg Greuther Fürth players
VfL Osnabrück players
Karlsruher SC players
Footballers from Munich
Men's association football defenders
2. Bundesliga players
3. Liga players
TSV 1860 Munich players
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https://en.wikipedia.org/wiki/Micronucleus
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Micronucleus is the name given to the small nucleus that forms whenever a chromosome or a fragment of a chromosome is not incorporated into one of the daughter nuclei during cell division. It usually is a sign of genotoxic events and chromosomal instability. Micronuclei are commonly seen in cancerous cells and may indicate genomic damage events that can increase the risk of developmental or degenerative diseases. Micronuclei form during anaphase from lagging acentric chromosome or chromatid fragments caused by incorrectly repaired or unrepaired DNA breaks or by nondisjunction of chromosomes. This incorrect segregation of chromosomes may result from hypomethylation of repeat sequences present in pericentromeric DNA, irregularities in kinetochore proteins or their assembly, dysfunctional spindle apparatus, or flawed anaphase checkpoint genes. Micronuclei can contribute to genome instability by promoting a catastrophic mutational event called chromothripsis. Many micronucleus assays have been developed to test for the presence of these structures and determine their frequency in cells exposed to certain chemicals or subjected to stressful conditions.
The term micronucleus may also refer to the smaller nucleus in ciliate protozoans, such as the Paramecium. In mitosis it divides by fission, and in conjugation a pair of gamete micronuclei undergo reciprocal fusion to form a zygote nucleus, which gives rise to the macronuclei and micronuclei of the individuals of the next cycle of
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https://en.wikipedia.org/wiki/Chromium%28II%29%20oxide
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Chromium(II) oxide (CrO) is an inorganic compound composed of chromium and oxygen. It is a black powder that crystallises in the rock salt structure.
Hypophosphites may reduce chromium(III) oxide to chromium(II) oxide:
H3PO2 + 2 Cr2O3 → 4 CrO + H3PO4
It is readily oxidized by the atmosphere. CrO is basic, while is acidic, and is amphoteric.
CrO occurs in the spectra of luminous red novae, which occur when two stars collide. It is not known why red novae are the only objects that feature this molecule; one possible explanation is an as-yet-unknown nucleosynthesis process.
See also
Chromium(IV) oxide
Chromium(VI) oxide
References
Chromium(II) compounds
Transition metal oxides
Reducing agents
Chromium–oxygen compounds
Rock salt crystal structure
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https://en.wikipedia.org/wiki/Solid-state%20lighting
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Solid-state lighting (SSL) is a type of lighting that uses semiconductor light-emitting diodes (LEDs), organic light-emitting diodes (OLED), or polymer light-emitting diodes (PLED) as sources of illumination rather than electrical filaments, plasma (used in arc lamps such as fluorescent lamps), or gas.
Solid state electroluminescence is used in SSL, as opposed to incandescent bulbs (which use thermal radiation) or fluorescent tubes. Compared to incandescent lighting, SSL creates visible light with reduced heat generation and less energy dissipation. Most common "white LEDs” convert blue light from a solid-state device to an (approximate) white light spectrum using photoluminescence, the same principle used in conventional fluorescent tubes.
The typically small mass of a solid-state electronic lighting device provides for greater resistance to shock and vibration compared to brittle glass tubes/bulbs and long, thin filament wires. They also eliminate filament evaporation, potentially increasing the life span of the illumination device.
Solid-state lighting is often used in traffic lights and is also used in modern vehicle lights, street and parking lot lights, train marker lights, building exteriors, remote controls etc. Controlling the light emission of LEDs may be done most effectively by using the principles of nonimaging optics. Solid-state lighting has made significant advances in industry. In the entertainment lighting industry, standard incandescent tungsten-halogen
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https://en.wikipedia.org/wiki/Killer%20Frost
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Killer Frost is a name used by several female supervillains and superheroes appearing in comic books published by DC Comics: Crystal Frost, Louise Lincoln, and Caitlin Snow. All three usually have some connection to the superhero Firestorm.
Various iterations of Killer Frost, primarily Crystal Frost and Louise Lincoln, have appeared in various animated projects and video games, with a majority of them voiced by Jennifer Hale. Additionally, Danielle Panabaker portrayed Caitlin Snow, Killer Frost (later renamed Frost), and Khione in The CW's Arrowverse franchise, such as the television series The Flash.
Fictional character biographies
Crystal Frost
Crystal Frost was the first incarnation, first appearing in Firestorm #3 (June 1978). While Frost was studying to be a scientist in Hudson University, she fell in love with her teacher Martin Stein. While working on a project in the Arctic, Frost was upset to learn that Stein did not reciprocate her feelings; Stein told a fellow researcher that Frost was a withdrawn student and that Stein had merely tried to draw her out of her shell, which Crystal completely misinterpreted. Frost accidentally locked herself in a thermafrost chamber but survived, being transformed in a way in which she was able to absorb heat from a living being and project cold and ice. Calling herself "Killer Frost", she began her murderous crusade against men and clashed with Firestorm on many occasions. Killer Frost eventually died after she absorbed too muc
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https://en.wikipedia.org/wiki/Crystal%20Beach
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Crystal Beach may refer to one of the following locations:
Crystal Beach, Ontario, community in Fort Erie, Ontario
Crystal Beach Park, amusement park in Crystal Beach, Ontario from 1888 to 1989
Crystal Beach (Nepean), community located in Ottawa, Ontario
Crystal Beach, Texas, historical beachfront near Galveston Bay, Texas
Crystal Beach (Florida), unincorporated community and a beach located in Pinellas County, Florida
White Crystal Beach, Maryland, unincorporated beach community in Cecil County, Maryland
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https://en.wikipedia.org/wiki/Haidingerite
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Haidingerite is a calcium arsenate mineral with formula Ca(AsO3OH)·H2O. It crystallizes in the orthorhombic crystal system as short prismatic to equant
crystals. It typically occurs as scaly, botryoidal or fibrous coatings. It is soft, Mohs hardness of 2 to 2.5, and has a specific gravity of 2.95. It has refractive indices of nα = 1.590, nβ = 1.602 and nγ = 1.638.
It was originally discovered in 1827 in Jáchymov, Czech Republic. It was named to honor Austrian mineralogist Wilhelm Karl Ritter von Haidinger (1795–1871). It occurs as a dehydration product of pharmacolite in the Getchell Mine, Nevada.
See also
List of minerals named after people
References
Palache, C., H. Berman, and C. Frondel (1951) Dana’s system of mineralogy, (7th edition), v. II, pp.708–709.
Calcium minerals
Arsenate minerals
Orthorhombic minerals
Minerals in space group 60
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https://en.wikipedia.org/wiki/Hedge%20%28linguistics%29
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In the linguistic sub-fields of applied linguistics and pragmatics, a hedge is a word or phrase used in a sentence to express ambiguity, probability, caution, or indecisiveness about the remainder of the sentence, rather than full accuracy, certainty, confidence, or decisiveness. Hedges can also allow speakers and writers to introduce (or occasionally even eliminate) ambiguity in meaning and typicality as a category member. Hedging in category membership is used in reference to the prototype theory, to signify the extent to which items are typical or atypical members of different categories. Hedges might be used in writing, to downplay a harsh critique or a generalization, or in speaking, to lessen the impact of an utterance due to politeness constraints between a speaker and addressee.
Typically, hedges are adjectives or adverbs, but can also consist of clauses such as one use of tag questions. In some cases, a hedge could be regarded as a form of euphemism. Linguists consider hedges to be tools of epistemic modality; allowing speakers and writers to signal a level of caution in making an assertion. Hedges are also used to distinguish items into multiple categories, where items can be in a certain category to an extent.
Types of hedges
Hedges may take the form of many different parts of speech, for example:
There might just be a few insignificant problems we need to address. (adjective)
The party was somewhat spoiled by the return of the parents. (adverb)
I'm not an expe
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https://en.wikipedia.org/wiki/Instantaneous%20phase%20and%20frequency
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Instantaneous phase and frequency are important concepts in signal processing that occur in the context of the representation and analysis of time-varying functions. The instantaneous phase (also known as local phase or simply phase) of a complex-valued function s(t), is the real-valued function:
where arg is the complex argument function.
The instantaneous frequency is the temporal rate of change of the instantaneous phase.
And for a real-valued function s(t), it is determined from the function's analytic representation, sa(t):
where represents the Hilbert transform of s(t).
When φ(t) is constrained to its principal value, either the interval or , it is called wrapped phase. Otherwise it is called unwrapped phase, which is a continuous function of argument t, assuming sa(t) is a continuous function of t. Unless otherwise indicated, the continuous form should be inferred.
Examples
Example 1
where ω > 0.
In this simple sinusoidal example, the constant θ is also commonly referred to as phase or phase offset. φ(t) is a function of time; θ is not. In the next example, we also see that the phase offset of a real-valued sinusoid is ambiguous unless a reference (sin or cos) is specified. φ(t) is unambiguously defined.
Example 2
where ω > 0.
In both examples the local maxima of s(t) correspond to φ(t) = 2N for integer values of N. This has applications in the field of computer vision.
Formulations
Instantaneous angular frequency is defined as:
and instantaneous (ordina
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https://en.wikipedia.org/wiki/Scheinerman%27s%20conjecture
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In mathematics, Scheinerman's conjecture, now a theorem, states that every planar graph is the intersection graph of a set of line segments in the plane. This conjecture was formulated by E. R. Scheinerman in his Ph.D. thesis (1984), following earlier results that every planar graph could be represented as the intersection graph of a set of simple curves in the plane . It was proven by .
For instance, the graph G shown below to the left may be represented as the intersection graph of the set of segments shown below to the right. Here, vertices of G are represented by straight line segments and edges of G are represented by intersection points.
Scheinerman also conjectured that segments with only three directions would be sufficient to represent 3-colorable graphs, and conjectured that analogously every planar graph could be represented using four directions. If a graph is represented with segments having only k directions
and no two segments belong to the same line, then the graph can be colored using k colors, one color for each direction. Therefore, if every planar graph can be represented in this way with only four directions,
then the four color theorem follows.
and proved that every bipartite planar graph can be represented as an intersection graph of horizontal and vertical line segments; for this result see also . proved that every triangle-free planar graph can be represented as an intersection graph of line segments having only three directions; this resu
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https://en.wikipedia.org/wiki/Wagner%27s%20theorem
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In graph theory, Wagner's theorem is a mathematical forbidden graph characterization of planar graphs, named after Klaus Wagner, stating that a finite graph is planar if and only if its minors include neither K5 (the complete graph on five vertices) nor K3,3 (the utility graph, a complete bipartite graph on six vertices). This was one of the earliest results in the theory of graph minors and can be seen as a forerunner of the Robertson–Seymour theorem.
Definitions and statement
A planar embedding of a given graph is a drawing of the graph in the Euclidean plane, with points for its vertices and curves for its edges, in such a way that the only intersections between pairs of edges are at a common endpoint of the two edges. A minor of a given graph is another graph formed by deleting vertices, deleting edges, and contracting edges. When an edge is contracted, its two endpoints are merged to form a single vertex. In some versions of graph minor theory the graph resulting from a contraction is simplified by removing self-loops and multiple adjacencies, while in other version multigraphs are allowed, but this variation makes no difference to Wagner's theorem.
Wagner's theorem states that every graph has either a planar embedding, or a minor of one of two types, the complete graph K5 or the complete bipartite graph K3,3. (It is also possible for a single graph to have both types of minor.)
If a given graph is planar, so are all its minors: vertex and edge deletion obviously pres
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https://en.wikipedia.org/wiki/Home%20runs%20allowed
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In baseball statistics, home runs allowed (HRA) signifies the total number of home runs a pitcher allowed.
The Major League Baseball record for the most home runs allowed by any pitcher belongs to Jamie Moyer (522 in his career). He gave up home runs while pitching for eight different teams across both leagues. Warren Spahn gave up the most National League home runs (434) and the American League record is 422, held by Frank Tanana. The Minnesota Twins' Bert Blyleven set Major League Baseball's season record in 1986, allowing a total of 50 home runs to opposing batters.
References
External links
Home runs allowed records
Pitching statistics
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https://en.wikipedia.org/wiki/Beta%20prime%20distribution
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In probability theory and statistics, the beta prime distribution (also known as inverted beta distribution or beta distribution of the second kind) is an absolutely continuous probability distribution. If has a beta distribution, then the odds has a beta prime distribution.
Definitions
Beta prime distribution is defined for with two parameters α and β, having the probability density function:
where B is the Beta function.
The cumulative distribution function is
where I is the regularized incomplete beta function.
The expected value, variance, and other details of the distribution are given in the sidebox; for , the excess kurtosis is
While the related beta distribution is the conjugate prior distribution of the parameter of a Bernoulli distribution expressed as a probability, the beta prime distribution is the conjugate prior distribution of the parameter of a Bernoulli distribution expressed in odds. The distribution is a Pearson type VI distribution.
The mode of a variate X distributed as is .
Its mean is if (if the mean is infinite, in other words it has no well defined mean) and its variance is if .
For , the k-th moment is given by
For with this simplifies to
The cdf can also be written as
where is the Gauss's hypergeometric function 2F1 .
Alternative parameterization
The beta prime distribution may also be reparameterized in terms of its mean μ > 0 and precision ν > 0 parameters ( p. 36).
Consider the parameterization μ = α/(β-1) and
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https://en.wikipedia.org/wiki/The%20Bedsit%20Tapes
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The Bedsit Tapes is a compilation of songs recorded by the synthpop/new wave duo Soft Cell before their record contract with Some Bizzare Records. The album, released on 1 August 2005, collects various songs recorded in an amateur studio at Leeds Metropolitan University, then called Leeds Polytechnic, in Leeds. The album includes three tracks which appeared on their rare independent 1980 release, Mutant Moments. The album has received criticism for not being comprehensive enough, excluding several rare cuts which have appeared on previous bootlegs. David Ball, the keyboardist, comments on the album in the liner notes.
The album includes a cover version of the song "Paranoid", originally recorded by British heavy metal band Black Sabbath.
Track listing
"Potential" (edited version with fade-out; the original segues into "L.O.V.E. Feelings")
"L.O.V.E. Feelings" (edited version)
"Metro MRX"
"Bleak Is My Favourite Cliché"
"Occupational Hazard"
"Mix"
"Factory Fun"
"Science Fiction Stories"
"Purely Functional"
"A Cut Above the Rest"
"Paranoid" (Geezer Butler, Tony Iommi, Ozzy Osbourne, Bill Ward)
"Excretory Eat Anorexia Nervosa"
"Cleansing Fanatic"
"Walking Make-Up Counter"
"Pyrex My Cuisine"
"Tupperware Party"
Notes
Tracks were recorded in bedrooms and the polytechnic art department studio in a very basic fashion between 1978 and 1980. Sleeve notes by Dave Ball.
References
2005 compilation albums
Soft Cell albums
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https://en.wikipedia.org/wiki/Klein%20paradox
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In 1929, physicist Oskar Klein obtained a surprising result by applying the Dirac equation to the familiar problem of electron scattering from a potential barrier. In nonrelativistic quantum mechanics, electron tunneling into a barrier is observed, with exponential damping. However, Klein's result showed that if the potential is at least of the order of the electron mass, , the barrier is nearly transparent. Moreover, as the potential approaches infinity, the reflection diminishes and the electron is always transmitted.
The immediate application of the paradox was to Rutherford's proton–electron model for neutral particles within the nucleus, before the discovery of the neutron. The paradox presented a quantum mechanical objection to the notion of an electron confined within a nucleus. This clear and precise paradox suggested that an electron could not be confined within a nucleus by any potential well. The meaning of this paradox was intensely debated at the time.
Massless particles
Consider a massless relativistic particle approaching a potential step of height with energy and momentum .
The particle's wave function, , follows the time-independent Dirac equation:
And is the Pauli matrix:
Assuming the particle is propagating from the left, we obtain two solutions — one before the step, in region (1) and one under the potential, in region (2):
where the coefficients , and are complex numbers.
Both the incoming and transmitted wave functions are associated wit
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https://en.wikipedia.org/wiki/Vector%20bundles%20on%20algebraic%20curves
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In mathematics, vector bundles on algebraic curves may be studied as holomorphic vector bundles on compact Riemann surfaces, which is the classical approach, or as locally free sheaves on algebraic curves C in a more general, algebraic setting (which can for example admit singular points).
Some foundational results on classification were known in the 1950s. The result of , that holomorphic vector bundles on the Riemann sphere are sums of line bundles, is now often called the Birkhoff–Grothendieck theorem, since it is implicit in much earlier work of on the Riemann–Hilbert problem.
gave the classification of vector bundles on elliptic curves.
The Riemann–Roch theorem for vector bundles was proved by , before the 'vector bundle' concept had really any official status. Although, associated ruled surfaces were classical objects. See Hirzebruch–Riemann–Roch theorem for his result. He was seeking a generalization of the Jacobian variety, by passing from holomorphic line bundles to higher rank. This idea would prove fruitful, in terms of moduli spaces of vector bundles. following on the work in the 1960s on geometric invariant theory.
See also
Hitchin system
References
Also in Collected Works vol. I
Algebraic curves
Vector bundles
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https://en.wikipedia.org/wiki/Isovanillin
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Isovanillin is a phenolic aldehyde, an organic compound and isomer of vanillin. It is a selective inhibitor of aldehyde oxidase. It is not a substrate of that enzyme, and is metabolized by aldehyde dehydrogenase into isovanillic acid, which could make it a candidate drug for use in alcohol aversion therapy. Isovanillin can be used as a precursor in the chemical total synthesis of morphine. The proposed metabolism of isovanillin (and vanillin) in rat has been described in literature, and is part of the WikiPathways machine readable pathway collection.
See also
Vanillin
2-Hydroxy-5-methoxybenzaldehyde
ortho-Vanillin
2-Hydroxy-4-methoxybenzaldehyde
References
Hydroxybenzaldehydes
Flavors
Perfume ingredients
Phenol ethers
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https://en.wikipedia.org/wiki/Far-infrared%20laser
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Far-infrared laser or terahertz laser (FIR laser, THz laser) is a laser with output wavelength in between 30-1000 µm (frequency 0.3-10 THz), in the far infrared or terahertz frequency band of the electromagnetic spectrum.
FIR lasers have application in terahertz spectroscopy, terahertz imaging as well in fusion plasma physics diagnostics. They can be used to detect explosives and chemical warfare agents, by the means of infrared spectroscopy or to evaluate the plasma densities by the means of interferometry techniques.
FIR lasers typically consist of a long (1–3 meters) waveguide filled with gaseous organic molecules, optically pumped or via HV discharge. They are highly inefficient, often require helium cooling, high magnetic fields, and/or are only line tunable. Efforts to develop smaller solid-state alternatives are under way.
The p-Ge (p-type germanium) laser is a tunable, solid state, far infrared laser which has existed for over 25 years. It operates in crossed electric and magnetic fields at liquid helium temperatures. Wavelength selection can be achieved by changing the applied electric/magnetic fields or through the introduction of intracavity elements.
Quantum cascade laser (QCL) is a construction of such alternative. It is a solid-state semiconductor laser that can operate continuously with output power of over 100 mW and wavelength of 9.5 µm. A prototype was already demonstrated. and potential use shown.
A molecular FIR laser optically pumped by a QCL has bee
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https://en.wikipedia.org/wiki/El%20Ajedrecista
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El Ajedrecista (, ) is an automaton built in 1912 by Leonardo Torres Quevedo in Madrid, one of the first autonomous machines capable of playing chess. As opposed to the human-operated The Turk and Ajeeb, El Ajedrecista had a true integrated automation built to play chess without human guidance. It played an endgame with three chess pieces, automatically moving a white king and a rook to checkmate the black king moved by a human opponent.
The device could be considered the first computer game in history. It created great excitement when it made its debut, at the University of Paris in 1914. It was first widely mentioned in Scientific American as "Torres and His Remarkable Automatic Devices" on November 6, 1915.
In 1951, El Ajedrecista defeated Savielly Tartakower at the Paris Cybernetic Congress, being the first Grandmaster to lose against a machine.
The automaton does not deliver checkmate in the minimum number of moves, nor always within the 50 moves allotted by the fifty-move rule, because of the simple algorithm that calculates the moves. It did, however, checkmate the opponent every time. If an illegal move was made by the opposite player, the automaton would signal it by turning on a light. If the opposing player made three illegal moves, the automaton would stop playing.
Technical description
Its internal construction was published by H. Vigneron. The pieces had a metallic mesh at their base, which closed an electric circuit that encoded their position in the board.
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https://en.wikipedia.org/wiki/List%20of%20hull%20classifications
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The list of hull classifications comprises an alphabetical list of the hull classification symbols used by the United States Navy to identify the type of a ship.
The combination of symbol and hull number identify a modern Navy ship uniquely. A heavily modified or repurposed ship may receive a new symbol, and either retain the hull number or receive a new one. Also, the system of symbols has changed a number of times since it was introduced in 1907, so ships' symbols sometimes change without anything being done to the physical ship.
Many of the symbols listed here are not presently in use. The Naval Vessel Register maintains an online database of U.S. Navy ships.
The 1975 ship reclassification of cruisers, frigates, and ocean escorts brought U.S. Navy classifications into line with other nations' classifications, and eliminated the perceived "cruiser gap" with the Soviet Navy.
If a ship's hull classification symbol has "T-" preceding it, that symbolizes that it is a ship of the Military Sealift Command, with a primarily civilian crew.
A
AALC: Amphibious Assault Landing Craft
AARCS: Air Raid Report Control Ship
AASGP: Amphibious Assault Ship, General Purpose
AB: Crane Ship
ABD: Advance base dock
ABSD: Advance base section dock
ABU: Boom defence vessel
AC: Collier
ACM: Auxiliary Mine Layer
ACR: Armored cruiser (pre-1920)
ACS: Auxiliary crane ship
ACV: Auxiliary Aircraft Carrier (1942, now CVE)
AD: Destroyer tender
ADC: Ammunition Storage Cargo s
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https://en.wikipedia.org/wiki/APOE
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APOE may refer to:
Apolipoprotein E, a main apoprotein of the chylomicron, also studied for its involvement in Alzheimer's disease risk
Professional Oklahoma Educators, an organization in Oklahoma formerly known as the Association of Professional Oklahoma Educators or APOE
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https://en.wikipedia.org/wiki/RNA-binding%20protein
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RNA-binding proteins (often abbreviated as RBPs) are proteins that bind to the double or single stranded RNA in cells and participate in forming ribonucleoprotein complexes.
RBPs contain various structural motifs, such as RNA recognition motif (RRM), dsRNA binding domain, zinc finger and others.
They are cytoplasmic and nuclear proteins. However, since most mature RNA is exported from the nucleus relatively quickly, most RBPs in the nucleus exist as complexes of protein and pre-mRNA called heterogeneous ribonucleoprotein particles (hnRNPs).
RBPs have crucial roles in various cellular processes such as: cellular function, transport and localization. They especially play a major role in post-transcriptional control of RNAs, such as: splicing, polyadenylation, mRNA stabilization, mRNA localization and translation. Eukaryotic cells express diverse RBPs with unique RNA-binding activity and protein–protein interaction. According to the Eukaryotic RBP Database (EuRBPDB), there are 2961 genes encoding RBPs in humans. During evolution, the diversity of RBPs greatly increased with the increase in the number of introns. Diversity enabled eukaryotic cells to utilize RNA exons in various arrangements, giving rise to a unique RNP (ribonucleoprotein) for each RNA. Although RBPs have a crucial role in post-transcriptional regulation in gene expression, relatively few RBPs have been studied systematically.It has now become clear that RNA–RBP interactions play important roles in many biologic
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https://en.wikipedia.org/wiki/Coframe
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In mathematics, a coframe or coframe field on a smooth manifold is a system of one-forms or covectors which form a basis of the cotangent bundle at every point. In the exterior algebra of , one has a natural map from , given by . If is dimensional a coframe is given by a section of such that . The inverse image under of the complement of the zero section of forms a principal bundle over , which is called the coframe bundle.
References
See also
Frame fields in general relativity
Moving frame
Differential geometry
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https://en.wikipedia.org/wiki/CR%20manifold
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In mathematics, a CR manifold, or Cauchy–Riemann manifold, is a differentiable manifold together with a geometric structure modeled on that of a real hypersurface in a complex vector space, or more generally modeled on an edge of a wedge.
Formally, a CR manifold is a differentiable manifold M together with a preferred complex distribution L, or in other words a complex subbundle of the complexified tangent bundle such that
(L is formally integrable)
.
The subbundle L is called a CR structure on the manifold M.
The abbreviation CR stands for "Cauchy–Riemann" or "Complex-Real".
Introduction and motivation
The notion of a CR structure attempts to describe intrinsically the property of being a hypersurface (or certain real submanifolds of higher codimension) in complex space by studying the properties of holomorphic vector fields which are tangent to the hypersurface.
Suppose for instance that M is the hypersurface of given by the equation
where z and w are the usual complex coordinates on . The holomorphic tangent bundle of consists of all linear combinations of the vectors
The distribution L on M consists of all combinations of these vectors which are tangent to M. The tangent vectors must annihilate the defining equation for M, so L consists of complex scalar multiples of
In particular, L consists of the holomorphic vector fields which annihilate F. Note that L gives a CR structure on M, for [L,L] = 0 (since L is one-dimensional) and since ∂/∂z and ∂/∂w are lin
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https://en.wikipedia.org/wiki/Still%20life%20%28cellular%20automaton%29
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In Conway's Game of Life and other cellular automata, a still life is a pattern that does not change from one generation to the next. The term comes from the art world where a still life painting or photograph depicts an inanimate scene. In cellular automata, a still life can be thought of as an oscillator with unit period.
Classification
A pseudo still life consists of two or more adjacent islands (connected components) which can be partitioned (either individually or as sets) into non-interacting subparts, which are also still lifes. This compares with a strict still life, which may not be partitioned in this way. A strict still life may have only a single island, or it may have multiple islands that depend on one another for stability, and thus cannot be decomposed. The distinction between the two is not always obvious, as a strict still life may have multiple connected components all of which are needed for its stability. However, it is possible to determine whether a still life pattern is a strict still life or a pseudo still life in polynomial time by searching for cycles in an associated skew-symmetric graph.
Examples
There are many naturally occurring still lifes in Conway's Game of Life. A random initial pattern will leave behind a great deal of debris, containing small oscillators and a large variety of still lifes.
The most common still life (i.e. that most likely to be generated from a random initial state) is the block. A pair of blocks placed side-by-side
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https://en.wikipedia.org/wiki/Beginner%27s%20luck
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Beginner's luck refers to the supposed phenomenon of novices experiencing disproportionate frequency of success or succeeding against an expert in a given activity. One would expect experts to outperform novices - when the opposite happens it is counter-intuitive, hence the need for a term to describe this phenomenon. The term is most often used in reference to a first attempt in sport or gambling, but is also used in many other diverse contexts. The term is also used when no skill whatsoever is involved, such as a first-time slot machine player winning the jackpot.
References
See also
Regression toward the mean
Amateur
Jinx
Luck
Mojo
Odds
Psychology
Rookie
U-shaped development
Gambling terminology
Sports terminology
Luck
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https://en.wikipedia.org/wiki/F%C3%A1ry%E2%80%93Milnor%20theorem
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In the mathematical theory of knots, the Fáry–Milnor theorem, named after István Fáry and John Milnor, states that three-dimensional smooth curves with small total curvature must be unknotted. The theorem was proved independently by Fáry in 1949 and Milnor in 1950. It was later shown to follow from the existence of quadrisecants .
Statement
If K is any closed curve in Euclidean space that is sufficiently smooth to define the curvature κ at each of its points, and if the total absolute curvature is less than or equal to 4π, then K is an unknot, i.e.:
The contrapositive tells us that if K is not an unknot, i.e. K is not isotopic to the circle, then the total curvature will be strictly greater than 4π. Notice that having the total curvature less than or equal to 4 is merely a sufficient condition for K to be an unknot; it is not a necessary condition. In other words, although all knots with total curvature less than or equal to 4π are the unknot, there exist unknots with curvature strictly greater than 4π.
Generalizations to non-smooth curves
For closed polygonal chains the same result holds with the integral of curvature replaced by the sum of angles between adjacent segments of the chain. By approximating arbitrary curves by polygonal chains, one may extend the definition of total curvature to larger classes of curves, within which the Fáry–Milnor theorem also holds (, ).
References
.
.
.
.
External links
. Fenner describes a geometric proof of the theorem, and of the
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https://en.wikipedia.org/wiki/Picene
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Picene is a hydrocarbon found in the pitchy residue obtained in the distillation of peat tar and of petroleum. This is distilled to dryness and the distillate repeatedly recrystallized from cymene. It may be synthetically prepared by the action of anhydrous aluminium chloride on a mixture of naphthalene and 1,2-dibromoethane, or by distilling a-dinaphthostilbene. It crystallizes in large colorless plates which possess a blue fluorescence. It is soluble in concentrated sulfuric acid with a green color. Chromic acid in glacial acetic acid solution oxidizes it to picene-quinone, picene-quinone carboxylic acid, and finally to phthalic acid.
When intercalated with potassium or rubidium and cooled to below 18 K, picene has been reported to exhibit superconductive properties. However, due to the apparent inability to reproduce this work, the superconducting nature of doped picene has been met with heavy scepticism.
Picene is also a major constituent of the hydrocarbon mineral idrialite.
See also
Olympicene, which has the same number of rings linked in a different way
References
Polycyclic aromatic hydrocarbons
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https://en.wikipedia.org/wiki/Propiolic%20acid
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Propiolic acid is the organic compound with the formula HC2CO2H. It is the simplest acetylenic carboxylic acid. It is a colourless liquid that crystallises to give silky crystals. Near its boiling point, it decomposes.
It is soluble in water and possesses an odor like that of acetic acid.
Preparation
It is prepared commercially by oxidizing propargyl alcohol at a lead electrode. It can also be prepared by decarboxylation of acetylenedicarboxylic acid.
Reactions and applications
Exposure to sunlight converts it into trimesic acid (benzene-1,3,5-tricarboxylic acid). It undergoes bromination to give dibromoacrylic acid. With hydrogen chloride it forms chloroacrylic acid. Its ethyl ester condenses with hydrazine to form pyrazolone.
It forms a characteristic explosive solid upon treatment to its aqueous solution with ammoniacal silver nitrate. An amorphous explosive precipitate forms with ammoniacal cuprous chloride.
Propiolates
Propiolates are esters or salts of propiolic acid. Common examples include methyl propiolate and ethyl propiolate.
See also
Propargyl
Propargyl alcohol
References
Carboxylic acids
Alkyne derivatives
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https://en.wikipedia.org/wiki/Flow%20battery
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A flow battery, or redox flow battery (after reduction–oxidation), is a type of electrochemical cell where chemical energy is provided by two chemical components dissolved in liquids that are pumped through the system on separate sides of a membrane. Ion transfer inside the cell (accompanied by flow of electric current through an external circuit) occurs through the membrane while both liquids circulate in their own respective space. Cell voltage is chemically determined by the Nernst equation and ranges, in practical applications, from 1.0 to 2.43 volts. The energy capacity is a function of the electrolyte volume and the power is a function of the surface area of the electrodes.
Various types of flow batteries have been demonstrated, including inorganic flow batteries and organic flow batteries. Under each category, flow battery design can be further classified into full flow batteries, semi-flow batteries, and membraneless flow batteries. The fundamental difference between conventional and flow batteries is that energy is stored in the electrode material in conventional batteries, while in flow batteries it is stored in the electrolyte. Patent Classifications for Flow Batteries have not been fully developed as of 2021. Cooperative Patent Classification considers RFBs as a subclass of regenerative fuel cell (H01M8/18), even though it is more appropriate to consider fuel cells as a subclass of flow batteries.
A flow battery may be used like a fuel cell (where new charged ne
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https://en.wikipedia.org/wiki/A%20band%20%28NATO%29
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The NATO A band is the obsolete designation given to the radio frequencies from 0 to 250 MHz (equivalent to wavelengths from 1.2 m upwards) during the cold war period. Since 1992 frequency allocations, allotment and assignments are in line to NATO Joint Civil/Military Frequency Agreement.
However, in order to identify military radio spectrum requirements, e.g. for crises management planning, training, Electronic warfare activities, or in military operations, this system is still in use.
NATO Radio spectrum designation
Examples to military frequency utilisation in this particular band
HF long distance radio communications
tactical UHF radio communications
aeronautical mobile service
References
Radio spectrum
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https://en.wikipedia.org/wiki/B%20band%20%28NATO%29
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The NATO B band is the obsolete designation given to the radio frequencies from 250 to 500 MHz (equivalent to wavelengths between 1.20 and 0.60 m) during the cold war period. Since 1992 frequency allocations, allotment and assignments are in line to NATO Joint Civil/Military Frequency Agreement (NJFA).
However, in order to identify military radio spectrum requirements, e.g. for crises management planning, training, Electronic warfare activities, or in military operations, this system is still in use.
Particularities
The NATO harmonised UHF band 225-400 MHz is also a subset of this particular band as defined by the NJFA.
References
Radio spectrum
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https://en.wikipedia.org/wiki/E%20band
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E band may refer to:
E (band), a Czech experimental rock band
E band (NATO), a radio frequency band from 2 to 3 GHz
E band (waveguide), a millimetre wave band from 60 to 90 GHz
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https://en.wikipedia.org/wiki/D%20band
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D band may refer to:
D (band), a Japanese visual kei rock band
D band (NATO), a radio frequency band from 1 to 2 GHz
D band (waveguide), a millimetre wave band from 110 to 170 GHz
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https://en.wikipedia.org/wiki/Dust%20solution
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In general relativity, a dust solution is a fluid solution, a type of exact solution of the Einstein field equation, in which the gravitational field is produced entirely by the mass, momentum, and stress density of a perfect fluid that has positive mass density but vanishing pressure. Dust solutions are an important special case of fluid solutions in general relativity.
Dust model
A pressureless perfect fluid can be interpreted as a model of a configuration of dust particles that locally move in concert and interact with each other only gravitationally, from which the name is derived. For this reason, dust models are often employed in cosmology as models of a toy universe, in which the dust particles are considered as highly idealized models of galaxies, clusters, or superclusters. In astrophysics, dust models have been employed as models of gravitational collapse.
Dust solutions can also be used to model finite rotating disks of dust grains; some examples are listed below. If superimposed somehow on a stellar model comprising a ball of fluid surrounded by vacuum, a dust solution could be used to model an accretion disk around a massive object; however, no such exact solutions that model rotating accretion disks are yet known due to the extreme mathematical difficulty of constructing them.
Mathematical definition
The stress–energy tensor of a relativistic pressureless fluid can be written in the simple form
Here
the world lines of the dust particles are the integr
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https://en.wikipedia.org/wiki/Poromechanics
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Poromechanics is a branch of physics and specifically continuum mechanics and acoustics that studies the behaviour of fluid-saturated porous media. A porous medium or a porous material is a solid referred to as matrix) permeated by an interconnected network of pores (voids) filled with a fluid (liquid or gas). Usually both solid matrix and the pore network, or pore space, are assumed to be continuous, so as to form two interpenetrating continua such as in a sponge. Natural substances including rocks, soils, biological tissues including heart and cancellous bone, and man-made materials such as foams and ceramics can be considered as porous media. Porous media whose solid matrix is elastic and the fluid is viscous are called poroelastic. A poroelastic medium is characterised by its porosity, permeability as well as the properties of its constituents (solid matrix and fluid).
The concept of a porous medium originally emerged in soil mechanics, and in particular in the works of Karl von Terzaghi, the father of soil mechanics. However a more general concept of a poroelastic medium, independent of its nature or application, is usually attributed to Maurice Anthony Biot (1905–1985), a Belgian-American engineer. In a series of papers published between 1935 and 1962 Biot developed the theory of dynamic poroelasticity (now known as Biot theory) which gives a complete and general description of the mechanical behaviour of a poroelastic medium. Biot's equations of the linear theory of
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https://en.wikipedia.org/wiki/Threading%20%28protein%20sequence%29
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In molecular biology, protein threading, also known as fold recognition, is a method of protein modeling which is used to model those proteins which have the same fold as proteins of known structures, but do not have homologous proteins with known structure.
It differs from the homology modeling method of structure prediction as it (protein threading) is used for proteins which do not have their homologous protein structures deposited in the Protein Data Bank (PDB), whereas homology modeling is used for those proteins which do. Threading works by using statistical knowledge of the relationship between the structures deposited in the PDB and the sequence of the protein which one wishes to model.
The prediction is made by "threading" (i.e. placing, aligning) each amino acid in the target sequence to a position in the template structure, and evaluating how well the target fits the template. After the best-fit template is selected, the structural model of the sequence is built based on the alignment with the chosen template. Protein threading is based on two basic observations: that the number of different folds in nature is fairly small (approximately 1300); and that 90% of the new structures submitted to the PDB in the past three years have similar structural folds to ones already in the PDB.
Classification of protein structure
The Structural Classification of Proteins (SCOP) database provides a detailed and comprehensive description of the structural and evolutionary relatio
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https://en.wikipedia.org/wiki/Grothendieck%E2%80%93Katz%20p-curvature%20conjecture
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In mathematics, the Grothendieck–Katz p-curvature conjecture is a local-global principle for linear ordinary differential equations, related to differential Galois theory and in a loose sense analogous to the result in the Chebotarev density theorem considered as the polynomial case. It is a conjecture of Alexander Grothendieck from the late 1960s, and apparently not published by him in any form.
The general case remains unsolved, despite recent progress; it has been linked to geometric investigations involving algebraic foliations.
Formulation
In a simplest possible statement the conjecture can be stated in its essentials for a vector system written as
for a vector v of size n, and an n×n matrix A of algebraic functions with algebraic number coefficients. The question is to give a criterion for when there is a full set of algebraic function solutions, meaning a fundamental matrix (i.e. n vector solutions put into a block matrix). For example, a classical question was for the hypergeometric equation: when does it have a pair of algebraic solutions, in terms of its parameters? The answer is known classically as Schwarz's list. In monodromy terms, the question is of identifying the cases of finite monodromy group.
By reformulation and passing to a larger system, the essential case is for rational functions in A and rational number coefficients. Then a necessary condition is that for almost all prime numbers p, the system defined by reduction modulo p should also have a full
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https://en.wikipedia.org/wiki/Dental%20pellicle
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The dental pellicle, or acquired pellicle, is a protein film that forms on the surface enamel, dentin, artificial crowns, and bridges by selective binding of glycoproteins from saliva that prevents continuous deposition of salivary calcium phosphate. It forms in seconds after a tooth is cleaned, or after chewing. It protects the tooth from the acids produced by oral microorganisms after consuming carbohydrates.
Stages
Pellicle
The surface of enamel and dentin attracts salivary glycoproteins and bacterial products creating the pellicle layer. This thin layer forms on the surface of the enamel within minutes of its exposure. These glycoproteins include proline-rich proteins that allow bacterial adhesion.
Pellicle somewhat protects enamel, but not dentin, from acid and abrasion.
Plaque formation
Plaque is a biofilm composed of several different kinds of bacteria and their products that develop over the enamel on the pellicle. Plaque formation takes several days to weeks and will cause the surrounding environment to become acidic, if not removed.
First bacteria
The first bacteria to attach to these pellicle glycoproteins are gram-positive, aerobic cocci such as Streptococcus sanguinis. These bacteria are able to replicate in the oxygen-rich environment of the oral cavity and form micro-colonies minutes after attachment.
Later bacteria
Other bacteria, including Streptococcus mutans, are able to grow in these colonies. Streptococcus mutans is important, because it is associ
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https://en.wikipedia.org/wiki/Gut%20microbiota
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Gut microbiota, gut microbiome, or gut flora, are the microorganisms, including bacteria, archaea, fungi, and viruses, that live in the digestive tracts of animals. The gastrointestinal metagenome is the aggregate of all the genomes of the gut microbiota. The gut is the main location of the human microbiome. The gut microbiota has broad impacts, including effects on colonization, resistance to pathogens, maintaining the intestinal epithelium, metabolizing dietary and pharmaceutical compounds, controlling immune function, and even behavior through the gut–brain axis.
The microbial composition of the gut microbiota varies across regions of the digestive tract. The colon contains the highest microbial density of any human-associated microbial community studied so far, representing between 300 and 1000 different species. Bacteria are the largest and to date, best studied component and 99% of gut bacteria come from about 30 or 40 species. Up to 60% of the dry mass of feces is bacteria. Over 99% of the bacteria in the gut are anaerobes, but in the cecum, aerobic bacteria reach high densities. It is estimated that the human gut microbiota have around a hundred times as many genes as there are in the human genome.
Overview
In humans, the gut microbiota has the largest numbers and species of bacteria compared to other areas of the body. The approximate number of bacteria composing the gut microbiota is about 1013-1014. In humans, the gut flora is established at one to two years af
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https://en.wikipedia.org/wiki/Systems%20biomedicine
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Systems biomedicine, also called systems biomedical science, is the application of systems biology to the understanding and modulation of developmental and pathological processes in humans, and in animal and cellular models. Whereas systems biology aims at modeling exhaustive networks of interactions (with the long-term goal of, for example, creating a comprehensive computational model of the cell), mainly at intra-cellular level, systems biomedicine emphasizes the multilevel, hierarchical nature of the models (molecule, organelle, cell, tissue, organ, individual/genotype, environmental factor, population, ecosystem) by discovering and selecting the key factors at each level and integrating them into models that reveal the global, emergent behavior of the biological process under consideration.
Such an approach will be favorable when the execution of all the experiments necessary to establish exhaustive models is limited by time and expense (e.g., in animal models) or basic ethics (e.g., human experimentation).
In the year of 1992, a paper on system biomedicine by Kamada T. was published (Nov.-Dec.), and an article on systems medicine and pharmacology by Zeng B.J. was also published (April) in the same time period.
In 2009, the first collective book on systems biomedicine was edited by Edison T. Liu and Douglas A. Lauffenburger.
In October 2008, one of the first research groups uniquely devoted to systems biomedicine was established at the European Institute of Oncology. O
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https://en.wikipedia.org/wiki/Mass%20flow%20%28life%20sciences%29
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In the life sciences, mass flow, also known as mass transfer and bulk flow, is the movement of fluids down a pressure or temperature gradient. As such, mass flow is a subject of study in both fluid dynamics and biology. Examples of mass flow include blood circulation and transport of water in vascular plant tissues. Mass flow is not to be confused with diffusion which depends on concentration gradients within a medium rather than pressure gradients of the medium itself.
Plant biology
In general, bulk flow in plant biology typically refers to the movement of water from the soil up through the plant to the leaf tissue through xylem, but can also be applied to the transport of larger solutes (e.g. sucrose) through the phloem.
Xylem
According to cohesion-tension theory, water transport in xylem relies upon the cohesion of water molecules to each other and adhesion to the vessel's wall via hydrogen bonding combined with the high water pressure of the plant's substrate and low pressure of the extreme tissues (usually leaves).
As in blood circulation in animals, (gas) embolisms may form within one or more xylem vessels of a plant. If an air bubble forms, the upward flow of xylem water will stop because the pressure difference in the vessel cannot be transmitted. Once these embolisms are nucleated , the remaining water in the capillaries begins to turn to water vapor. When these bubbles form rapidly by cavitation, the "snapping" sound can be used to measure the rate of cavitation
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https://en.wikipedia.org/wiki/Principal%20ideal%20theorem
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In mathematics, the principal ideal theorem of class field theory, a branch of algebraic number theory, says that extending ideals gives a mapping on the class group of an algebraic number field to the class group of its Hilbert class field, which sends all ideal classes to the class of a principal ideal. The phenomenon has also been called principalization, or sometimes capitulation.
Formal statement
For any algebraic number field K and any ideal I of the ring of integers of K, if L is the Hilbert class field of K, then
is a principal ideal αOL, for OL the ring of integers of L and some element α in it.
History
The principal ideal theorem was conjectured by , and was the last remaining aspect of his program on class fields to be completed, in 1929.
reduced the principal ideal theorem to a question about finite abelian groups: he showed that it would follow if the transfer from a finite group to its derived subgroup is trivial. This result was proved by Philipp Furtwängler (1929).
References
Ideals (ring theory)
Group theory
Homological algebra
Theorems in algebraic number theory
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https://en.wikipedia.org/wiki/Grammar-based%20code
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Grammar-based codes or Grammar-based compression are compression algorithms based on the idea of constructing a context-free grammar (CFG) for the string to be compressed. Examples include universal lossless data compression algorithms. To compress a data sequence , a grammar-based code transforms into a context-free grammar .
The problem of finding a smallest grammar for an input sequence (smallest grammar problem) is known to be NP-hard, so many grammar-transform algorithms are proposed from theoretical and practical viewpoints.
Generally, the produced grammar is further compressed by statistical encoders like arithmetic coding.
Examples and characteristics
The class of grammar-based codes is very broad. It includes block codes, the multilevel pattern matching (MPM) algorithm, variations of the incremental parsing Lempel-Ziv code, and many other new universal lossless compression algorithms.
Grammar-based codes are universal in the sense that they can achieve asymptotically the entropy rate of any stationary, ergodic source with a finite alphabet.
Practical algorithms
The compression programs of the following are available from external links.
Sequitur is a classical grammar compression algorithm that sequentially translates an input text into a CFG, and then the produced CFG is encoded by an arithmetic coder.
Re-Pair is a greedy algorithm using the strategy of most-frequent-first substitution. The compressive performance is powerful, although the main memory space
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https://en.wikipedia.org/wiki/Cristallo
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Cristallo is a glass that is totally clear (like rock crystal), without the slight yellow or greenish color originating from iron oxide impurities. This effect is achieved through small additions of manganese oxide. Often Cristallo has a low lime content, which makes it prone to glass corrosion (otherwise known as glass disease).
The invention of Cristallo glass is attributed to Angelo Barovier around 1450.
Materials
In addition to common glass making materials manganese, quartz pebbles, and alume catino, a particularly suitable form of soda ash, are used in the making of cristallo glass.
Rather than using common sand, crushed quartz pebbles were used instead. The quartz pebbles were typically from the Ticino and the Adige rivers. The quartz pebbles went through a rigorous screening process before being selected for use in cristallo production. The quartz pebbles had to be free of yellow and black veins and also had to be able to produce sparks when struck with steel.
If the quartz pebbles passed the selection process then the pebbles were heated to the point where the stones began to glow and then placed into cold water. Then the pebbles were crushed and ground.
The typical flux used in the production of cristallo was called alume catino. Alume catino was derived from the ash of the salsola soda and salsola kali bushes that grew in the Levantine coastal region. It was found to contain high and constant amounts of sodium and calcium carbonates, necessary to make workabl
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https://en.wikipedia.org/wiki/Grapefruit%20seed%20extract
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Grapefruit seed extract (GSE), also known as citrus seed extract, is a liquid extract derived from the seeds, pulp, and white membranes of grapefruit. GSE is prepared by grinding the grapefruit seed and juiceless pulp, then mixing with glycerin. Commercially available GSEs sold to consumers are made from the seed, pulp, and glycerin blended together. GSE is sold as a dietary supplement and is used in cosmetics.
Grapefruit history
The grapefruit is a subtropical citrus tree grown for its fruit which was originally named the "forbidden fruit" of Barbados. The fruit was first documented in 1750 by Rev. Griffith Hughes when describing specimens from Barbados. All parts of the fruit can be used. The fruit is mainly consumed for its tangy juice. The peel can be processed into aromatherapy oils and is also a source of dietary fiber. The seed and pulp, as byproducts of the juice industry, are retrieved for GSE processing or sold as cattle feed.
Efficacy
Despite claims that GSE has antimicrobial effects, there is no scientific evidence that GSE has such properties. Some evidence indicates that the suspected antimicrobial activity of GSE was due to the contamination or adulteration of commercial GSE preparations with synthetic antimicrobials or preservatives. These chemicals were not present in grapefruit seed extracts prepared in the laboratory, and GSE preparations without the contaminants were found to possess no detectable antimicrobial effect. Although citrus seed extract is
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https://en.wikipedia.org/wiki/Jet%20group
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In mathematics, a jet group is a generalization of the general linear group which applies to Taylor polynomials instead of vectors at a point. A jet group is a group of jets that describes how a Taylor polynomial transforms under changes of coordinate systems (or, equivalently, diffeomorphisms).
Overview
The k-th order jet group Gnk consists of jets of smooth diffeomorphisms φ: Rn → Rn such that φ(0)=0.
The following is a more precise definition of the jet group.
Let k ≥ 2. The differential of a function f: Rk → R can be interpreted as a section of the cotangent bundle of RK given by df: Rk → T*Rk. Similarly, derivatives of order up to m are sections of the jet bundle Jm(Rk) = Rk × W, where
Here R* is the dual vector space to R, and Si denotes the i-th symmetric power. A smooth function f: Rk → R has a prolongation jmf: Rk → Jm(Rk) defined at each point p ∈ Rk by placing the i-th partials of f at p in the Si((R*)k) component of W.
Consider a point . There is a unique polynomial fp in k variables and of order m such that p is in the image of jmfp. That is, . The differential data x′ may be transferred to lie over another point y ∈ Rn as jmfp(y) , the partials of fp over y.
Provide Jm(Rn) with a group structure by taking
With this group structure, Jm(Rn) is a Carnot group of class m + 1.
Because of the properties of jets under function composition, Gnk is a Lie group. The jet group is a semidirect product of the general linear group and a connected, simply connected
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https://en.wikipedia.org/wiki/Connellite
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Connellite is a rare mineral species, a hydrous copper chloro-sulfate, Cu19(OH)32(SO4)Cl4·3H2O, crystallizing in the hexagonal system. It occurs as tufts of very delicate acicular crystals of a fine blue color, and is associated with other copper minerals of secondary origin, such as cuprite and malachite. Its occurrence in Cornwall, England, was noted by Philip Rashleigh in 1802, and it was first examined chemically by Prof Arthur Connell FRSE in 1847, after whom it is named.
The type locality is Wheal Providence at Carbis Bay in Cornwall. Outside Cornwall it has been found in over 200 locations worldwide including Namaqualand in South Africa and at Bisbee, Arizona (US).
References
Copper(II) minerals
Halide minerals
Sulfate minerals
Hexagonal minerals
Minerals in space group 194
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https://en.wikipedia.org/wiki/Lamb%E2%80%93Oseen%20vortex
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In fluid dynamics, the Lamb–Oseen vortex models a line vortex that decays due to viscosity. This vortex is named after Horace Lamb and Carl Wilhelm Oseen.
Mathematical description
Oseen looked for a solution for the Navier–Stokes equations in cylindrical coordinates with velocity components of the form
where is the circulation of the vortex core. Navier-Stokes equations lead to
which, subject to the conditions that it is regular at and becomes unity as , leads to
where is the kinematic viscosity of the fluid. At , we have a potential vortex with concentrated vorticity at the axis; and this vorticity diffuses away as time passes.
The only non-zero vorticity component is in the direction, given by
The pressure field simply ensures the vortex rotates in the circumferential direction, providing the centripetal force
where ρ is the constant density
Generalized Oseen vortex
The generalized Oseen vortex may obtained by looking for solutions of the form
that leads to the equation
Self-similar solution exists for the coordinate , provided , where is a constant, in which case . The solution for may be written according to Rott (1958) as
where is an arbitrary constant. For , the classical Lamb–Oseen vortex is recovered. The case corresponds to the axisymmetric stagnation point flow, where is a constant. When , , a Burgers vortex is a obtained. For arbitrary , the solution becomes , where is an arbitrary constant. As , Burgers vortex is recovered.
See also
T
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https://en.wikipedia.org/wiki/Batchelor%20vortex
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In fluid dynamics, Batchelor vortices, first described by George Batchelor in a 1964 article, have been found useful in analyses of airplane vortex wake hazard problems.
The model
The Batchelor vortex is an approximate solution to the Navier–Stokes equations obtained using a boundary layer approximation. The physical reasoning behind this approximation is the assumption that the axial gradient of the flow field of interest is of much smaller magnitude than the radial gradient.
The axial, radial and azimuthal velocity components of the vortex are denoted , and respectively and can be represented in cylindrical coordinates as follows:
The parameters in the above equations are
, the free-stream axial velocity,
, the velocity scale (used for nondimensionalization),
, the length scale (used for nondimensionalization),
, a measure of the core size, with initial core size and representing viscosity,
, the swirl strength, given as a ratio between the maximum tangential velocity and the core velocity.
Note that the radial component of the velocity is zero and that the axial and azimuthal components depend only on .
We now write the system above in dimensionless form by scaling time by a factor . Using the same symbols for the dimensionless variables, the Batchelor vortex can be expressed in terms of the dimensionless variables as
where denotes the free stream axial velocity and is the Reynolds number.
If one lets and considers an infinitely large swirl number then
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https://en.wikipedia.org/wiki/Jim%20Eno
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Jim Eno (born February 8, 1966) is the drummer and one of the founding members of the Austin, Texas band Spoon. He is also a record producer and a semiconductor chip designer.
Overview
Eno was born in Rhode Island. He studied electrical engineering at North Carolina State University and worked as a hardware design engineer at Compaq Computer Corporation in Houston before moving to Austin in 1992 to design microchips for Motorola. Since joining Spoon he has also worked for Metta Technology as an electrical engineer, but has worked entirely in music since mid-2006.
Eno met the lead singer of Spoon, Britt Daniel, when replacing the drummer of Daniel's former band The Alien Beats. He owns and operates a studio called Public Hi-Fi in Austin, Texas, where the band has often recorded. He has co-produced albums for Spoon and has produced albums for other bands, including !!!, Heartless Bastards, The Relatives and The Strange Boys (discography below). Eno is also an accomplished engineer, working alongside producers Tony Visconti and Steve Berlin. He recently produced two songs for the solo debut of former Voxtrot frontman, Ramesh Srivastava, and mixed all three of the "EP 1" songs.
Starting at the Austin City Limits Festival in 2012 and continuing with SXSW 2013, 2014 and 2015, Jim Eno has been curating exclusive sessions for Spotify. Artists featured include: The Shins, Palma Violets, Father John Misty, The 1975, Phantogram, Poliça, Jagwar Ma, The Hold Steady, Rag'n'Bone Ma
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https://en.wikipedia.org/wiki/Mandelic%20acid
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Mandelic acid is an aromatic alpha hydroxy acid with the molecular formula C6H5CH(OH)CO2H. It is a white crystalline solid that is soluble in water and polar organic solvents. It is a useful precursor to various drugs. The molecule is chiral. The racemic mixture is known as paramandelic acid.
Isolation, synthesis, occurrence
Mandelic acid was discovered in 1831 by the German pharmacist Ferdinand Ludwig Winckler (1801–1868) while heating amygdalin, an extract of bitter almonds, with diluted hydrochloric acid. The name is derived from the German "Mandel" for "almond".
Mandelic acid is usually prepared by the acid-catalysed hydrolysis of mandelonitrile, which is the cyanohydrin of benzaldehyde. Mandelonitrile can also be prepared by reacting benzaldehyde with sodium bisulfite to give the corresponding adduct, forming mandelonitrile with sodium cyanide, which is hydrolyzed:
Alternatively, it can be prepared by base hydrolysis of phenylchloroacetic acid as well as dibromacetophenone. It also arises by heating phenylglyoxal with alkalis.
Biosynthesis
Mandelic acid is a substrate or product of several biochemical processes called the mandelate pathway. Mandelate racemase interconverts the two enantiomers via a pathway that involves cleavage of the alpha-CH bond. Mandelate dehydrogenase is yet another enzyme on this pathway. Mandelate also arises from trans-cinnamate via phenylacetic acid, which is hydroxylated. Phenylpyruvic acid is another precursor to mandelic acid.
Deri
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https://en.wikipedia.org/wiki/Nikolay%20Umov
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Nikolay Alekseevich Umov (; January 23, 1846 – January 15, 1915) was a Russian physicist and mathematician known for discovering the concept of Umov-Poynting vector and Umov effect.
Biography
Umov was born in 1846 in Simbirsk (present-day Ulyanovsk) in the family of a military doctor. He graduated from the Physics and Mathematics department of Moscow State University in 1867 and became a Professor of Physics in 1875. He studied theoretical physics by reading works of Gabriel Lamé, Clebsch and Clausius, that made a significant impact on the originality of his later ideas in physics.
Umov became the head of the Physics department of Moscow State University (MSU) after Aleksandr Stoletov died in 1896. Together with Pyotr Lebedev, Umov actively participated in founding the Physical Institute at the MSU.
He organized several educational societies. He was the president of the Moscow Society of Nature Explorers for 17 years. He was among the first Russian scientists who acknowledged the importance of the theory of relativity. In 1911, along with a group of leading professors, he left Moscow University in protest of reactionary actions of the government. Umov died in 1915 in Moscow.
Contribution to physics
Umov was the first who introduced in physics such basic concepts as speed and direction of movement of energy, which are now associated with Umov-Poynting vector, and density of energy in a given point of space. During his work in Odessa from 1873 to 1874, Umov published first
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https://en.wikipedia.org/wiki/Dielectric%20breakdown%20model
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Dielectric breakdown model (DBM) is a macroscopic mathematical model combining the diffusion-limited aggregation model with electric field. It was developed by Niemeyer, Pietronero, and Weismann in 1984. It describes the patterns of dielectric breakdown of solids, liquids, and even gases, explaining the formation of the branching, self-similar Lichtenberg figures.
See also
Eden growth model
Lichtenberg figure
Diffusion-limited aggregation
References
External links
Dielectric Breakdown Model
Electricity
Mathematical modeling
Electrical breakdown
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https://en.wikipedia.org/wiki/Prime%20decomposition%20of%203-manifolds
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In mathematics, the prime decomposition theorem for 3-manifolds states that every compact, orientable 3-manifold is the connected sum of a unique (up to homeomorphism) finite collection of prime 3-manifolds.
A manifold is prime if it cannot be presented as a connected sum of more than one manifold, none of which is the sphere of the same dimension. This condition is necessary since for any manifold M of dimension it is true that
(where means the connected sum of and ). If is a prime 3-manifold then either it is or the non-orientable bundle over
or it is irreducible, which means that any embedded 2-sphere bounds a ball. So the theorem can be restated to say that there is a unique connected sum decomposition into irreducible 3-manifolds and fiber bundles of over
The prime decomposition holds also for non-orientable 3-manifolds, but the uniqueness statement must be modified slightly: every compact, non-orientable 3-manifold is a connected sum of irreducible 3-manifolds and non-orientable bundles over This sum is unique as long as we specify that each summand is either irreducible or a non-orientable bundle over
The proof is based on normal surface techniques originated by Hellmuth Kneser. Existence was proven by Kneser, but the exact formulation and proof of the uniqueness was done more than 30 years later by John Milnor.
References
3-manifolds
Manifolds
Theorems in differential geometry
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https://en.wikipedia.org/wiki/Child%20mortality
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Child mortality is the mortality of children under the age of five. The child mortality rate (also under-five mortality rate) refers to the probability of dying between birth and exactly five years of age expressed per 1,000 live births.
It encompasses neonatal mortality and infant mortality (the probability of death in the first year of life).
Reduction of child mortality is reflected in several of the United Nations' Sustainable Development Goals. Target 3.2 is "by 2030, end preventable deaths of newborns and children under 5 years of age, with all countries aiming to reduce … under‑5 mortality to at least as low as 25 per 1,000 live births."
Child mortality rates have decreased in the last 40 years. Rapid progress has resulted in a significant decline in preventable child deaths since 1990, with the global under-5 mortality rate declining by over half between 1990 and 2016. While in 1990, 12.6 million children under age five died, in 2016 that number fell to 5.6 million children, and then in 2020, the global number fell again to 5 million. However, despite advances, there are still 15,000 under-five deaths per day from largely preventable causes. About 80 per cent of these occur in sub-Saharan Africa and South Asia, and just 6 countries account for half of all under-five deaths: China, India, Pakistan, Nigeria, Ethiopia and the Democratic Republic of the Congo. 45% of these children died during the first 28 days of life. Death rates were highest among children under age
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https://en.wikipedia.org/wiki/Triton%20%28demogroup%29
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Triton (TRN) was a demogroup active in the PC demoscene from 1992 to about 1996.
History
Triton's first demo, Crystal Dream, was released in the summer of 1992 and won the PC demo competition at the Hackerence V demo party. Their second and last demo, Crystal Dream 2, was released June 1993 and won the demo competition at The Computer Crossroads 1993 party in Gothenburg. In 1993 they released a multi-channel MOD composer called Fast Tracker, followed by the XM module composer Fast Tracker 2 in 1994.
Triton created a commercial demo for Gravis Ultrasound cards.
Most of their work was done using a combination of x86 assembler and Pascal using either Turbo Pascal or Borland Pascal 7 compilers.
Triton began developing on a fighting game named Into the Shadows. A game demo showing a character was released in 1995, but the development was stopped thereafter. In 1998, some of Triton's members founded the computer game development company Starbreeze Studios, that merged with O3 Games in 2001.
Members
Team founders (1992):
Vogue (Magnus Högdahl) - code, music
Mr. H (Fredrik Huss) - code
Loot (Anders Aldengård) - graphics, raytracing
Members hired in 1993:
Lizardking (Gustaf Grefberg) - music
Joachim (Joachim Barrum) - graphics
Alt (Mikko Tähtinen) - graphics
Releases
Crystal Dream (1992, demo, 1st at Hackerence 92)
Crystal Dream 2 (1993, demo, 1st at The Computer Crossroads 93)
FastTracker 2 (1995, tracker)
References
External links
Triton archive on Pouet
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https://en.wikipedia.org/wiki/Glossary%20of%20arithmetic%20and%20diophantine%20geometry
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This is a glossary of arithmetic and diophantine geometry in mathematics, areas growing out of the traditional study of Diophantine equations to encompass large parts of number theory and algebraic geometry. Much of the theory is in the form of proposed conjectures, which can be related at various levels of generality.
Diophantine geometry in general is the study of algebraic varieties V over fields K that are finitely generated over their prime fields—including as of special interest number fields and finite fields—and over local fields. Of those, only the complex numbers are algebraically closed; over any other K the existence of points of V with coordinates in K is something to be proved and studied as an extra topic, even knowing the geometry of V.
Arithmetic geometry can be more generally defined as the study of schemes of finite type over the spectrum of the ring of integers. Arithmetic geometry has also been defined as the application of the techniques of algebraic geometry to problems in number theory.
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D
E
F
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H
I
K
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M
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O
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R
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See also
Arithmetic topology
Arithmetic dynamics
References
Further reading
Dino Lorenzini (1996), An invitation to arithmetic geometry, AMS Bookstore,
Diophantine geometry
Algebraic geometry
Geometry
Wikipedia glossaries using description lists
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https://en.wikipedia.org/wiki/Height%20function
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A height function is a function that quantifies the complexity of mathematical objects. In Diophantine geometry, height functions quantify the size of solutions to Diophantine equations and are typically functions from a set of points on algebraic varieties (or a set of algebraic varieties) to the real numbers.
For instance, the classical or naive height over the rational numbers is typically defined to be the maximum of the numerators and denominators of the coordinates (e.g. for the coordinates ), but in a logarithmic scale.
Significance
Height functions allow mathematicians to count objects, such as rational points, that are otherwise infinite in quantity. For instance, the set of rational numbers of naive height (the maximum of the numerator and denominator when expressed in lowest terms) below any given constant is finite despite the set of rational numbers being infinite. In this sense, height functions can be used to prove asymptotic results such as Baker's theorem in transcendental number theory which was proved by .
In other cases, height functions can distinguish some objects based on their complexity. For instance, the subspace theorem proved by demonstrates that points of small height (i.e. small complexity) in projective space lie in a finite number of hyperplanes and generalizes Siegel's theorem on integral points and solution of the S-unit equation.
Height functions were crucial to the proofs of the Mordell–Weil theorem and Faltings's theorem by and res
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https://en.wikipedia.org/wiki/I%20band%20%28NATO%29
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The NATO I band is the obsolete designation given to the radio frequencies from 8 000 to 10 000 MHz (equivalent to wavelengths between 3.75 and 3 cm) during the Cold War period. Since 1992 frequency allocations, allotment and assignments are in line to NATO Joint Civil/Military Frequency Agreement (NJFA).
However, in order to identify military radio spectrum requirements, e.g. for crises management planning, training, Electronic warfare activities, or in military operations, this system is still in use.
References
Radio spectrum
Microwave bands
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https://en.wikipedia.org/wiki/J%20band
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J band may refer to:
J band (infrared), an atmospheric transmission window centred on 1.25 μm
J band (JRC), radio frequency bands from 139.5 to 140.5 and 148 to 149 MHz
J band (NATO), a radio frequency band from 10 to 20 GHz
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https://en.wikipedia.org/wiki/G%20band
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G band may refer to:
G band (IEEE), a millimetre wave band from 110 to 300 GHz
G band (NATO), a radio frequency band from 4 to 6 GHz
G band, representing a green hued wavelength of in the photometric systems adopted by astronomers
G banding, in cytogenetics
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https://en.wikipedia.org/wiki/F%20band%20%28NATO%29
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The NATO F band is the obsolete designation given to the radio frequencies from 3 000 to 4 000 MHz (equivalent to wavelengths between 10 and 7.5 cm) during the cold war period. Since 1992 frequency allocations, allotment and assignments are in line to NATO Joint Civil/Military Frequency Agreement (NJFA).
However, in order to identify military radio spectrum requirements, e.g. for crises management planning, training, Electronic warfare activities, or in military operations, this system is still in use.
References
Radio spectrum
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https://en.wikipedia.org/wiki/H%20band
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H band may refer to:
H band (infrared), an atmospheric transmission window centred on 1.65 μm
H band (NATO), a radio frequency band from 6 to 8 GHz
H band, part of the sarcomere
See also
H line (disambiguation)
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https://en.wikipedia.org/wiki/M%20band%20%28NATO%29
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The NATO M band is the obsolete designation given to the radio frequencies from 60 to 100 GHz (equivalent to wavelengths between 5 and 3 mm) during the cold war period. Since 1992 frequency allocations, allotment and assignments are in line to NATO Joint Civil/Military Frequency Agreement (NJFA).
However, in order to identify military radio spectrum requirements, e.g. for crises management planning, training, Electronic warfare activities, or in military operations, this system is still in use.
The NATO M band is also a subset of the EHF band as defined by the ITU. It intersects with the V (50–75 GHz) and W band (75–110 GHz) of the older IEEE classification system.
References
Radio spectrum
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https://en.wikipedia.org/wiki/Maurice%20Anthony%20Biot
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Maurice Anthony Biot (May 25, 1905 – September 12, 1985) was a Belgian-American applied physicist. He made contributions in thermodynamics, aeronautics, geophysics, earthquake engineering, and electromagnetism. Particularly, he was accredited as the founder of the theory of poroelasticity.
Born in Antwerp, Belgium, Biot studied at Catholic University of Leuven in Belgium where he received a bachelor's degrees in philosophy (1927), mining engineering (1929) and electrical engineering (1930), and Doctor of Science in 1931. He obtained his Ph.D. in Aeronautical Science from the California Institute of Technology in 1932 under Theodore von Kármán.
In 1930s and 1940s Biot worked at Harvard University, the Catholic University of Leuven, Columbia University and Brown University, and later for a number of companies and government agencies, including NASA during the Space Program in the 1960s. Since 1969, Biot became a private consultant for various companies and agencies, and particularly for Shell Research and Development.
Biot's early work with von Kármán and during the World War II working for the US Navy Bureau of Aeronautics led to the development of the three-dimensional theory of aircraft flutter. During the period between 1932 and 1942, he conceived and then fully developed the response spectrum method (RSM) for earthquake engineering. For irreversible thermodynamics, Biot utilized the variational approach and was the first to introduce the dissipation function and the min
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https://en.wikipedia.org/wiki/Poroelasticity
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Poroelasticity is a field in materials science and mechanics that studies the interaction between fluid flow and solids deformation within a linear porous medium and it is an extension of elasticity and porous medium flow (diffusion equation). The deformation of the medium influences the flow of the fluid and vice versa. The theory was proposed by Maurice Anthony Biot (1935, 1941) as a theoretical extension of soil consolidation models developed to calculate the settlement of structures placed on fluid-saturated porous soils.
The theory of poroelasticity has been widely applied in geomechanics, hydrology, biomechanics, tissue mechanics, cell mechanics, and micromechanics.
An intuitive sense of the response of a saturated elastic porous medium to mechanical loading can be developed by thinking about, or experimenting with, a fluid-saturated sponge. If a fluid- saturated sponge is compressed, fluid will flow from the sponge. If the sponge is in a fluid reservoir and compressive pressure is subsequently removed, the sponge will reimbibe the fluid and expand. The volume of the sponge will also increase if its exterior openings are sealed and the pore fluid pressure is increased. The basic ideas underlying the theory of poroelastic materials are that the pore fluid pressure contributes to the total stress in the porous matrix medium and that the pore fluid pressure alone can strain the porous matrix medium. There is fluid movement in a porous medium due to differences in pore flu
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https://en.wikipedia.org/wiki/Sputum%20culture
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A sputum culture is a test to detect and identify bacteria or fungi that infect the lungs or breathing passages. Sputum is a thick fluid produced in the lungs and in the adjacent airways. Normally, fresh morning sample is preferred for the bacteriological examination of sputum. A sample of sputum is collected in a sterile, wide-mouthed, dry, leak-proof and break-resistant plastic-container and sent to the laboratory for testing. Sampling may be performed by sputum being expectorated (produced by coughing), induced (saline is sprayed in the lungs to induce sputum production), or taken via an endotracheal tube with a protected specimen brush (commonly used on patients on respirators) in an intensive care setting. For selected organisms such as Cytomegalovirus or "Pneumocystis jiroveci" in specific clinical settings (immunocompromised patients) a bronchoalveolar lavage might be taken by an experienced pneumologist. If no bacteria or fungi grow, the culture is negative. If organisms that can cause the infection (Pathogenicity organisms) grow, the culture is positive. The type of bacterium or fungus is identified by microscopy, colony morphology and biochemical tests of bacterial growth.
If bacteria or fungi that can cause infection grow in the culture, other tests can determine which antimicrobial agent will most effectively treat the infection. This is called susceptibility or sensitivity testing.
In a hospital setting, a sputum culture is most commonly ordered if a patient ha
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https://en.wikipedia.org/wiki/Euclid%27s%20theorem
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Euclid's theorem is a fundamental statement in number theory that asserts that there are infinitely many prime numbers. It was first proved by Euclid in his work Elements. There are several proofs of the theorem.
Euclid's proof
Euclid offered a proof published in his work Elements (Book IX, Proposition 20), which is paraphrased here.
Consider any finite list of prime numbers p1, p2, ..., pn. It will be shown that at least one additional prime number not in this list exists. Let P be the product of all the prime numbers in the list: P = p1p2...pn. Let q = P + 1. Then q is either prime or not:
If q is prime, then there is at least one more prime that is not in the list, namely, q itself.
If q is not prime, then some prime factor p divides q. If this factor p were in our list, then it would divide P (since P is the product of every number in the list); but p also divides P + 1 = q, as just stated. If p divides P and also q, then p must also divide the difference of the two numbers, which is (P + 1) − P or just 1. Since no prime number divides 1, p cannot be in the list. This means that at least one more prime number exists beyond those in the list.
This proves that for every finite list of prime numbers there is a prime number not in the list. In the original work, as Euclid had no way of writing an arbitrary list of primes, he used a method that he frequently applied, that is, the method of generalizable example. Namely, he picks just three primes and using the general meth
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https://en.wikipedia.org/wiki/Belyi%27s%20theorem
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In mathematics, Belyi's theorem on algebraic curves states that any non-singular algebraic curve C, defined by algebraic number coefficients, represents a compact Riemann surface which is a ramified covering of the Riemann sphere, ramified at three points only.
This is a result of G. V. Belyi from 1979. At the time it was considered surprising, and it spurred Grothendieck to develop his theory of dessins d'enfant, which describes non-singular algebraic curves over the algebraic numbers using combinatorial data.
Quotients of the upper half-plane
It follows that the Riemann surface in question can be taken to be the quotient
H/Γ
(where H is the upper half-plane and Γ is a subgroup of finite index in the modular group) compactified by cusps. Since the modular group has non-congruence subgroups, it is not the conclusion that any such curve is a modular curve.
Belyi functions
A Belyi function is a holomorphic map from a compact Riemann surface S to the complex projective line P1(C) ramified only over three points, which after a Möbius transformation may be taken to be . Belyi functions may be described combinatorially by dessins d'enfants.
Belyi functions and dessins d'enfants – but not Belyi's theorem – date at least to the work of Felix Klein; he used them in his article to study an 11-fold cover of the complex projective line with monodromy group PSL(2,11).
Applications
Belyi's theorem is an existence theorem for Belyi functions, and has subsequently been much used
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https://en.wikipedia.org/wiki/Riemann%E2%80%93Roch%20theorem%20for%20surfaces
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In mathematics, the Riemann–Roch theorem for surfaces describes the dimension of linear systems on an algebraic surface. The classical form of it was first given by , after preliminary versions of it were found by and . The sheaf-theoretic version is due to Hirzebruch.
Statement
One form of the Riemann–Roch theorem states that if D is a divisor on a non-singular projective surface then
where χ is the holomorphic Euler characteristic, the dot . is the intersection number, and K is the canonical divisor. The constant χ(0) is the holomorphic Euler characteristic of the trivial bundle, and is equal to 1 + pa, where pa is the arithmetic genus of the surface. For comparison, the Riemann–Roch theorem for a curve states that χ(D) = χ(0) + deg(D).
Noether's formula
Noether's formula states that
where χ=χ(0) is the holomorphic Euler characteristic, c12 = (K.K) is a Chern number and the self-intersection number of the canonical class K, and e = c2 is the topological Euler characteristic. It can be used to replace the
term χ(0) in the Riemann–Roch theorem with topological terms; this gives the Hirzebruch–Riemann–Roch theorem for surfaces.
Relation to the Hirzebruch–Riemann–Roch theorem
For surfaces, the Hirzebruch–Riemann–Roch theorem is essentially the Riemann–Roch theorem for surfaces combined with the Noether formula. To see this, recall that for each divisor D on a surface there is an invertible sheaf L = O(D) such that the linear system of D is more or less the space of sect
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https://en.wikipedia.org/wiki/Fc%20receptor
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In immunology, an Fc receptor is a protein found on the surface of certain cells – including, among others, B lymphocytes, follicular dendritic cells, natural killer cells, macrophages, neutrophils, eosinophils, basophils, human platelets, and mast cells – that contribute to the protective functions of the immune system.
Its name is derived from its binding specificity for a part of an antibody known as the Fc (fragment crystallizable) region. Fc receptors bind to antibodies that are attached to infected cells or invading pathogens. Their activity stimulates phagocytic or cytotoxic cells to destroy microbes, or infected cells by antibody-mediated phagocytosis or antibody-dependent cell-mediated cytotoxicity. Some viruses such as flaviviruses use Fc receptors to help them infect cells, by a mechanism known as antibody-dependent enhancement of infection.
Classes
There are several different types of Fc receptors (abbreviated FcR), which are classified based on the type of antibody that they recognize. The Latin letter used to identify a type of antibody is converted into the corresponding Greek letter, which is placed after the 'Fc' part of the name. For example, those that bind the most common class of antibody, IgG, are called Fc-gamma receptors (FcγR), those that bind IgA are called Fc-alpha receptors (FcαR) and those that bind IgE are called Fc-epsilon receptors (FcεR). The classes of FcR's are also distinguished by the cells that express them (macrophages, granulocytes,
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https://en.wikipedia.org/wiki/Copper%28II%29%20fluoride
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Copper(II) fluoride is an inorganic compound with the chemical formula CuF2. The anhydrous form is a white, ionic, crystalline, hygroscopic solid with a distorted rutile-type crystal structure, similar to other fluorides of chemical formulae MF2 (where M is a metal). The dihydrate, , is blue in colour.
Structure
Copper(II) fluoride has a monoclinic crystal structure and cannot achieve a higher-symmetry structure. It forms rectangular prisms with a parallelogram base. Each copper ion has four neighbouring fluoride ions at 1.93 Å separation and two further away at 2.27 Å. This distorted octahedral [4+2] coordination is a consequence of the Jahn–Teller effect in d9 copper(II), and leads to a distorted rutile structure similar to that of chromium(II) fluoride, , which is a d4 compound.
Uses
Copper (II) fluoride can be used to make fluorinated aromatic hydrocarbons by reacting with aromatic hydrocarbons in an oxygen-containing atmosphere at temperatures above 450 °C (842 °F). This reaction is simpler than the Sandmeyer reaction, but is only effective in making compounds that can survive at the temperature used. A coupled reaction using oxygen and 2 HF regenerates the copper(II) fluoride, producing water. This method has been proposed as a "greener" method of producing fluoroaromatics since it avoids producing toxic waste products such as ammonium fluoride.
Chemistry
Copper(II) fluoride can be synthesized from copper and fluorine at temperatures of 400 °C (752 °F). It occurs as
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https://en.wikipedia.org/wiki/Melodic%20pattern
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In music and jazz improvisation, a melodic pattern (or motive) is a cell or germ serving as the basis for repetitive pattern. It is a figure that can be used with any scale. It is used primarily for solos because, when practiced enough, it can be extremely useful when improvising. "Sequence" refers to the repetition of a part at a higher or lower pitch, and melodic sequence is differentiated from harmonic sequence. One example of melodic motive and sequence are the pitches of the first line, "Send her victorious," repeated, a step lower, in the second line, "Happy and glorious," from "God Save the Queen".
"A melodic pattern is just what the name implies: a melody with some sort of fixed pattern to it." "The strong theme or motive is stated. It is repeated more or less exactly, but at a different pitch level."
See also
Color (isorhythm)
Imitation (music)
Melody type
Lick (music)
Phrase (music)
References
Further reading
Hanon, C.L. (2000) The Virtuoso Pianist. . Cited in Baerman, Noah (2003). Big Book of Jazz Piano Improvisation, p. 33. .
Lateef, Yusef (1981). Repository of Scales and Melodic Patterns. Fana Music. Cited in Baerman (2003), p. 33.
Slonimsky, Nicolas (2000). Thesaurus of Scales and Melodic Patterns. . Cited in Baerman (2003), p. 33.
Melody
Repetition (music)
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https://en.wikipedia.org/wiki/Copper%20indium%20gallium%20selenide
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Copper indium gallium (di)selenide (CIGS) is a I-III-VI2 semiconductor material composed of copper, indium, gallium, and selenium. The material is a solid solution of copper indium selenide (often abbreviated "CIS") and copper gallium selenide. It has a chemical formula of CuIn1−xGaxSe2, where the value of x can vary from 0 (pure copper indium selenide) to 1 (pure copper gallium selenide). CIGS is a tetrahedrally bonded semiconductor, with the chalcopyrite crystal structure, and a bandgap varying continuously with x from about 1.0 eV (for copper indium selenide) to about 1.7 eV (for copper gallium selenide).
Structure
CIGS is a tetrahedrally bonded semiconductor, with the chalcopyrite crystal structure. Upon heating it transforms to the zincblende form and the transition temperature decreases from 1045 °C for x = 0 to 805 °C for x = 1.
Applications
It is best known as the material for CIGS solar cells a thin-film technology used in the photovoltaic industry. In this role, CIGS has the advantage of being able to be deposited on flexible substrate materials, producing highly flexible, lightweight solar panels. Improvements in efficiency have made CIGS an established technology among alternative cell materials.
See also
Copper indium gallium selenide solar cells
CZTS
List of CIGS companies
References
Semiconductor materials
Copper(I) compounds
Indium compounds
Gallium compounds
Selenides
Renewable energy
Dichalcogenides
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https://en.wikipedia.org/wiki/Quantum%20heterostructure
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A quantum heterostructure is a heterostructure in a substrate (usually a semiconductor material), where size restricts the movements of the charge carriers forcing them into a quantum confinement. This leads to the formation of a set of discrete energy levels at which the carriers can exist. Quantum heterostructures have sharper density of states than structures of more conventional sizes.
Quantum heterostructures are important for fabrication of short-wavelength light-emitting diodes and diode lasers, and for other optoelectronic applications, e.g. high-efficiency photovoltaic cells.
Examples of quantum heterostructures confining the carriers in quasi-two, -one and -zero dimensions are:
Quantum wells
Quantum wires
Quantum dots
References
See also
http://www.ecse.rpi.edu/~schubert/Light-Emitting-Diodes-dot-org/chap04/chap04.htm
Kitaev's periodic table
Quantum electronics
Nanomaterials
Semiconductor structures
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https://en.wikipedia.org/wiki/Climate%20of%20Adelaide
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Adelaide has a Mediterranean climate (Köppen climate classification Csa), with mild wet winters and hot dry summers.
Seasonal variation
Summer (December to February)
In summer the average minimum is around 15.1 to 16.8 °C and the average maximum is around 26.8 to 28.5 °C, but there is considerable variation and Adelaide can usually expect several days a year where temperatures reach the mid/high 30s to low 40s. On a few occasions the temperature has even nudged into the mid 40s. These high temperatures usually occur when hot northerly winds blow hot air down south from central Australia, causing the mercury to spike. However, the weather, like Melbourne, Victoria, can be rather changeable as it is not uncommon to have days where the temperature peaks in the low 20s when there is a cool southerly wind blowing cooler air from the Southern Ocean. Occasionally, the mercury may fail to get to 20 degrees, even in the peak of summer.
Rainfall is unreliable, light and infrequent throughout summer. The average in January and February is around 20mm, but completely rainless months are by no means uncommon.
Autumn (March – May)
In autumn, the weather is generally mild. Average minimum temperatures vary between 10.4 and 15.2 °C, while maximums vary between 18.6 and 26 °C.
There is very little rainfall until late Autumn.
Winter (June to August)
In winter the average maximum is around 14 to 16 °C and the average minimum around 7 to 9 °C, although temperatures again can fluctuate. No
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