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https://en.wikipedia.org/wiki/Alveolar%E2%80%93arterial%20gradient | The Alveolar–arterial gradient (A-, or A–a gradient), is a measure of the difference between the alveolar concentration (A) of oxygen and the arterial (a) concentration of oxygen. It is a useful parameter for narrowing the differential diagnosis of hypoxemia.
The A–a gradient helps to assess the integrity of the alveolar capillary unit. For example, in high altitude, the arterial oxygen is low but only because the alveolar oxygen () is also low. However, in states of ventilation perfusion mismatch, such as pulmonary embolism or right-to-left shunt, oxygen is not effectively transferred from the alveoli to the blood which results in an elevated A-a gradient.
In a perfect system, no A-a gradient would exist: oxygen would diffuse and equalize across the capillary membrane, and the pressures in the arterial system and alveoli would be effectively equal (resulting in an A-a gradient of zero). However even though the partial pressure of oxygen is about equilibrated between the pulmonary capillaries and the alveolar gas, this equilibrium is not maintained as blood travels further through pulmonary circulation. As a rule, is always higher than by at least 5–10 mmHg, even in a healthy person with normal ventilation and perfusion. This gradient exists due to both physiological right-to-left shunting and a physiological V/Q mismatch caused by gravity-dependent differences in perfusion to various zones of the lungs. The bronchial vessels deliver nutrients and oxygen to certain lung |
https://en.wikipedia.org/wiki/Radio%20Narvik | Radio Narvik was a local radio station which covered the whole of Ofoten, including Narvik, Ankenes, Ballangen and Bjerkvik. The frequency was FM 103,5 and 150,5 in all areas. It was also possible to listen via internet radio.
In 2005 Radio Narvik was bought by the newspaper Fremover, becoming part of Jærradiogruppen AS. In December 2008, the radio station was closed down due to lack of income.
External links
Radio Narvik (Norwegian)
Radio stations in Norway
Radio stations disestablished in 2008
Defunct mass media in Norway |
https://en.wikipedia.org/wiki/Viverroidea | Viverroidea is a clade within feliformia, containing both the family Viverridae, and the superfamily Herpestoidea.
Classification
Infraorder Viverroidea
Family Viverridae (civets and allies)
Superfamily Herpestoidea
Family Eupleridae (Malagasy carnivorans)
Family Herpestidae (mongooses and allies)
Family Hyaenidae (hyenas and aardwolf)
Family †Lophocyonidae
Family †Percrocutidae
Phylogenetic tree
The phylogenetic relationships of Viverroidea are shown in the following cladogram:
References
Mammal infraorders
Mammal taxonomy
Taxa named by John Edward Gray |
https://en.wikipedia.org/wiki/Plateau%20potentials | Plateau potentials, caused by persistent inward currents (PICs), are a type of electrical behavior seen in neurons.
Spinal Cord
Plateau potentials are of particular importance to spinal cord motor systems. PICs are set up by the influence of descending monoaminergic reticulospinal pathways. Metabotropic neurotransmitters, via monoaminergic input such as 5-HT and norepinephrine, modulate the activity of dendritic L-type Calcium channels that allow a sustained, positive, inward current into the cell. This leads to a lasting depolarisation. In this state, the cell fires action potentials independent of synaptic input. The PICs can be turned off via the activation of high-frequency inhibitory input at which point the cell returns to a resting state.
Olfactory Bulb
Periglomerular cells, inhibitory interneurons that surround and innervate olfactory glomeruli, have also been shown to exhibit plateau potentials.
Cortex and Hippocampus
Plateau potentials are also seen in the cortical, and hippocampal pyramidal neurons. Using iontophoretic, or two-photon glutamate uncaging experiments, it has been discovered that these plateau potentials include activities of voltage dependent calcium channels and NMDA receptors.
References
Electrophysiology
Action potentials |
https://en.wikipedia.org/wiki/Digital%20down%20converter | In digital signal processing, a digital down-converter (DDC) converts a digitized, band-limited signal to a lower frequency signal at a lower sampling rate in order to simplify the subsequent radio stages. The process can preserve all the information in the frequency band of interest of the original signal. The input and output signals can be real or complex samples. Often the DDC converts from the raw radio frequency or intermediate frequency down to a complex baseband signal.
Architecture
A DDC consists of three subcomponents: a direct digital synthesizer (DDS), a low-pass filter (LPF), and a downsampler (which may be integrated into the low-pass filter).
The DDS generates a complex sinusoid at the intermediate frequency (IF). Multiplication of the intermediate frequency with the input signal creates images centered at the sum and difference frequency (which follows from the frequency shifting properties of the Fourier transform). The lowpass filters pass the difference (i.e. baseband) frequency while rejecting the sum frequency image, resulting in a complex baseband representation of the original signal. Assuming judicious choice of IF and LPF bandwidth, the complex baseband signal is mathematically equivalent to the original signal. In its new form, it can readily be downsampled and is more convenient to many DSP algorithms.
Any suitable low-pass filter can be used including FIR, IIR and CIC filters. The most common choice is a FIR filter for low amounts of decima |
https://en.wikipedia.org/wiki/List%20of%20CSI%3A%20Miami%20characters | List of characters for the CBS television series, CSI: Miami.
Equations
During CSI: Miamis opening credits, several actors' names morph in and out of equations.
Notable cast members
CSI: Miami ran for ten seasons between 2002 and 2012, and featured a cast of thirteen regulars. David Caruso, as Lieutenant Horatio Caine, was afforded the starring credit, while Emily Procter was credited second to him. Kim Delaney, the female lead in the episodes she appeared, was credited as and, while Rory Cochrane was afforded this credit following his departure, despite being previously credited as with. Also holding and positions were Adam Rodriguez, during seasons 9 and 10 (he was previously credited directly following Procter), and Eddie Cibrian during season 8. Sofia Milos (season 3), Khandi Alexander (seasons 1–6), Jonathan Togo (seasons 3–10), Rex Linn (seasons 5–10), Eva LaRue (seasons 5–10), Megalyn Echikunwoke (season 7), and Omar Benson Miller (seasons 8–10) were credited consistently in that order.
Crossover characters
CSI: Miami hosted several crossover episodes during its ten seasons on air. Gary Sinise, as Detective Mac Taylor, and Melina Kanakaredes as his partner, Detective Stella Bonasera, were introduced during a 2004 episode of CSI: Miami, as were the rest of the CSI: NY cast. Sinise reprised his role during Miamis fourth season, while CSI: Crime Scene Investigation alumnus Laurence Fishburne appeared as his established character during part one of a three part CSI: |
https://en.wikipedia.org/wiki/Ubiquinol | A ubiquinol is an electron-rich (reduced) form of coenzyme Q (ubiquinone). The term most often refers to ubiquinol-10, with a 10-unit tail most commonly found in humans.
The natural ubiquinol form of coenzyme Q is 2,3-dimethoxy-5-methyl-6-poly prenyl-1,4-benzoquinol, where the polyprenylated side-chain is 9-10 units long in mammals. Coenzyme Q10 (CoQ10) exists in three redox states, fully oxidized (ubiquinone), partially reduced (semiquinone or ubisemiquinone), and fully reduced (ubiquinol). The redox functions of ubiquinol in cellular energy production and antioxidant protection are based on the ability to exchange two electrons in a redox cycle between ubiquinol (reduced) and the ubiquinone (oxidized) form.
Characteristics
Because humans can synthesize ubiquinol, it is not classed as a vitamin.
Bioavailability
It is well-established that CoQ10 is not well absorbed into the body, as has been published in many peer-reviewed scientific journals. Since the ubiquinol form has two additional hydrogens, it results in the conversion of two ketone groups into hydroxyl groups on the active portion of the molecule. This causes an increase in the polarity of the CoQ10 molecule and may be a significant factor behind the observed enhanced bioavailability of ubiquinol.
Content in foods
Varying amounts of ubiquinol are found in different types of food. An analysis of a range of foods found ubiquinol to be present in 66 out of 70 items and accounted for 46% of the total coenzyme Q10 in |
https://en.wikipedia.org/wiki/Glutamyl%20aminopeptidase | Glutamyl aminopeptidase (, aminopeptidase A, aspartate aminopeptidase, angiotensinase A, glutamyl peptidase, Ca2+-activated glutamate aminopeptidase, membrane aminopeptidase II, antigen BP-1/6C3 of mouse B lymphocytes, L-aspartate aminopeptidase, angiotensinase A2) is an enzyme encoded by the gene. Glutamyl aminopeptidase has also recently been designated CD249 (cluster of differentiation 249).
Glutamyl aminopeptidase is a zinc-dependent membrane-bound aminopeptidase that catalyzes the cleavage of glutamatic and aspartatic amino acid residues from the N-terminus of polypeptides. The enzyme degrades vasoconstricting angiotensin II into angiotensin III and therefore helps to regulate blood pressure.
References
External links
The MEROPS online database for peptidases and their inhibitors: M01.003
Clusters of differentiation
Zinc enzymes |
https://en.wikipedia.org/wiki/Glutamate%20carboxypeptidase | Glutamate carboxypeptidase (, carboxypeptidase G, carboxypeptidase G1, carboxypeptidase G2, glutamyl carboxypeptidase, N-pteroyl-L-glutamate hydrolase) is an enzyme. This enzyme catalyses the following chemical reaction
Release of C-terminal glutamate residues from a wide range of N-acylating moieties, including peptidyl, aminoacyl, benzoyl, benzyloxycarbonyl, folyl and pteroyl groups
This zinc enzyme is produced by pseudomonads, Flavobacterium sp. and Acinetobacter sp.
See also
Glutamate carboxypeptidase II
References
External links
EC 3.4.17 |
https://en.wikipedia.org/wiki/Carboxypeptidase%20C | Carboxypeptidase C (, carboxypeptidase Y, serine carboxypeptidase I, cathepsin A, lysosomal protective protein, deamidase, lysosomal carboxypeptidase A, phaseolin) is an enzyme. This enzyme catalyses the following chemical reaction
Release of a C-terminal amino acid with broad specificity
This enzyme is a carboxypeptidase with optimum activity at pH 4.5-6.0. It is inhibited by diisopropyl fluorophosphate.
See also
Cathepsin A
References
External links
EC 3.4.16 |
https://en.wikipedia.org/wiki/Cathepsin%20A | Cathepsin A is an enzyme that is classified both as a cathepsin and a carboxypeptidase. In humans, it is encoded by the CTSA gene.
Function
This gene encodes a glycoprotein that associates with lysosomal enzymes beta-galactosidase and neuraminidase to form a complex of high-molecular-weight multimers. The formation of this complex provides a protective role for stability and activity. It is protective for β-galactosidase and neuraminidase.
Clinical significance
Deficiencies in this gene are linked to multiple forms of galactosialidosis.
Interactions
Cathepsin A has been shown to interact with NEU1.
References
Further reading
External links
EC 3.4.16
Proteases
Cathepsins |
https://en.wikipedia.org/wiki/Schouten%E2%80%93Nijenhuis%20bracket | In differential geometry, the Schouten–Nijenhuis bracket, also known as the Schouten bracket, is a type of graded Lie bracket defined on multivector fields on a smooth manifold extending the Lie bracket of vector fields. There are two different versions, both rather confusingly called by the same name. The most common version is defined on alternating multivector fields and makes them into a Gerstenhaber algebra, but there is also another version defined on symmetric multivector fields, which is more or less the same as the Poisson bracket on the cotangent bundle. It was invented by Jan Arnoldus Schouten (1940, 1953) and its properties were investigated by his student Albert Nijenhuis (1955). It is related to but not the same as the Nijenhuis–Richardson bracket and the Frölicher–Nijenhuis bracket.
Definition and properties
An alternating multivector field is a section of the exterior algebra ∧∗TM over the tangent bundle of a manifold M. The alternating multivector fields form a graded supercommutative ring with the product of a and b written as ab (some authors use a∧b). This is dual to the usual algebra of differential forms Ω∗M by the pairing on homogeneous elements:
The degree of a multivector A in is defined to be |A| = p.
The skew symmetric Schouten–Nijenhuis bracket is the unique extension of the Lie bracket of vector fields to a graded bracket on the space of alternating multivector fields that makes the alternating multivector fields into a Gerstenhaber al |
https://en.wikipedia.org/wiki/CIGL-FM | CIGL-FM is a Canadian radio station, broadcasting on the assigned frequency of 97.1 MHz in Belleville, Ontario, with the on-air branding of Mix 97. It airs a hot adult contemporary format.
History
The station first started in 1962 as CJBQ-FM, then changed its callsign to CIGL-FM in 1978. The former CJBQ callsign currently belongs to its sister station CJBQ. The call letters CIGL were often featured with seagulls in logos and advertisements, leading many to conclude that the call letters were a short form for "seagull".
Until 1995 CIGL featured essentially a "Beautiful Music" format playing many instrumental renditions of popular songs by artists such as Percy Faith, Nelson Riddle, Richard Clayderman, Frank Mills and Floyd Cramer. As the popularity of the Beautiful Music format decreased throughout the 1980s all around North America, more soft rock vocal music was added, including light songs by Kenny Rogers, Glenn Medieros and many others. On July 1, 1995, the station was re-branded as Mix 97, and adopted its current format.
CIGL is owned by Quinte Broadcasting.
On July 14, 2021, Quinte Broadcasting received CRTC approval to decrease the radiated power from 50,000 to 18,000 watts, increasing the effective antenna height above average terrain from 48.5 to 121 metres, and amending the existing coordinates of the transmitter site.
References
External links
Mix 97
Igl
Igl
Radio stations established in 1962
1962 establishments in Ontario |
https://en.wikipedia.org/wiki/Quasi-birth%E2%80%93death%20process | In queueing models, a discipline within the mathematical theory of probability, the quasi-birth–death process describes a generalisation of the birth–death process. As with the birth-death process it moves up and down between levels one at a time, but the time between these transitions can have a more complicated distribution encoded in the blocks.
Discrete time
The stochastic matrix describing the Markov chain has block structure
where each of A0, A1 and A2 are matrices and A*0, A*1 and A*2 are irregular matrices for the first and second levels.
Continuous time
The transition rate matrix for a quasi-birth-death process has a tridiagonal block structure
where each of B00, B01, B10, A0, A1 and A2 are matrices. The process can be viewed as a two dimensional chain where the block structure are called levels and the intra-block structure phases. When describing the process by both level and phase it is a continuous-time Markov chain, but when considering levels only it is a semi-Markov process (as transition times are then not exponentially distributed).
Usually the blocks have finitely many phases, but models like the Jackson network can be considered as quasi-birth-death processes with infinitely (but countably) many phases.
Stationary distribution
The stationary distribution of a quasi-birth-death process can be computed using the matrix geometric method.
References
Queueing theory
Markov processes |
https://en.wikipedia.org/wiki/Vector%20path | In graphics design, a vector path is a drawn or generated outline that represents a series of smooth straight (vector) lines instead of raster dots (or bitmap
dots). Therefore, the paths are independent of resolution. They also have a special feature that bitmaps and vectors do not have - the ability to change based on their new size or shape.
Vector graphics |
https://en.wikipedia.org/wiki/Search-based%20software%20engineering | Search-based software engineering (SBSE) applies metaheuristic search techniques such as genetic algorithms, simulated annealing and tabu search to software engineering problems. Many activities in software engineering can be stated as optimization problems. Optimization techniques of operations research such as linear programming or dynamic programming are often impractical for large scale software engineering problems because of their computational complexity or their assumptions on the problem structure. Researchers and practitioners use metaheuristic search techniques, which impose little assumptions on the problem structure, to find near-optimal or "good-enough" solutions.
SBSE problems can be divided into two types:
black-box optimization problems, for example, assigning people to tasks (a typical combinatorial optimization problem).
white-box problems where operations on source code need to be considered.
Definition
SBSE converts a software engineering problem into a computational search problem that can be tackled with a metaheuristic. This involves defining a search space, or the set of possible solutions. This space is typically too large to be explored exhaustively, suggesting a metaheuristic approach. A metric (also called a fitness function, cost function, objective function or quality measure) is then used to measure the quality of potential solutions. Many software engineering problems can be reformulated as a computational search problem.
The term "searc |
https://en.wikipedia.org/wiki/Stephen%20Harvey%20%28biologist%29 | Stephen C. Harvey (born 1940) is a structural biologist with research interest in nucleic acids, the ribosome, virus structure and high density lipoprotein. He is currently an adjunct professor in the Department of Biochemistry and Biophysics at the University of Pennsylvania and professor emeritus and Georgia Research Alliance eminent scholar emeritus in the School of Biology at the Georgia Institute of Technology, Atlanta, Georgia. Harvey did his undergraduate work at the University of California (Berkeley), where he received his A.B. degree in physics. In the 1960s, he worked as a rocket test engineer on the Apollo program (the lunar mission project) and served with the Peace Corps in Colombia, before entering graduate school in physics at Dartmouth College, where he received his PhD in biophysics in 1971. Before moving to Georgia Tech in 2003, Harvey was professor in the Department of Biochemistry and Molecular Genetics at the University of Alabama at Birmingham (UAB).
He is past president of the Biophysical Society and co-author, with J. Andrew McCammon, of the classic book on Molecular Dynamics, Dynamics of Proteins and Nucleic Acids (Cambridge University Press, 1987; ). Harvey is married to the artist Marie Weaver. They live in Philadelphia, Pennsylvania.
The Marie Weaver and Steve Harvey Endowed Scholarship Fund for Graphic Design was set up in 2003 by the University of Alabama at Birmingham in honor of associate professor of graphic design Marie Weaver and her |
https://en.wikipedia.org/wiki/Nijenhuis%20bracket | In mathematics there are four different but related brackets named after Albert Nijenhuis, giving Lie superalgebra structures to various spaces of tensors:
Frölicher–Nijenhuis bracket (defined on vector valued forms, extending the Lie bracket of vector fields)
Nijenhuis–Richardson bracket (defined on vector valued forms; this has a different degree to the Frölicher-Nijenhuis bracket)
Schouten–Nijenhuis bracket (2 versions, defined on either symmetric or antisymmetric multivectors) |
https://en.wikipedia.org/wiki/List%20of%20British%20Rail%20power%20classifications | The British Transport Commission, later British Railways, used engine power output to categorise its requirements for the new main line diesel locomotive fleet following the 1955 modernisation plan. The locomotives built and put into service are listed below classified with the TOPS class numbers that were introduced in the early 1970s.
Type 1
Locomotives classed as Type 1 were of 1,000 bhp or below.
Class 14
Class 15
Class 16
Class 17
Class 20
Certain members of Class 21
Certain members of Class 22
Type 2
Locomotives classed as Type 2 produced between 1,001 bhp and 1,499 bhp.
Certain members of Class 21
Certain members of Class 22
Class 23
Class 24
Class 25
Class 26
Class 27
Class 28
Class 29
Class 30/31
Type 3
Locomotives classed as Type 3 produced between 1,500 bhp and 1,999 bhp.
Class 33/34
Class 35
Class 37
Type 4
Locomotives classed as Type 4 produced between 2,000 bhp and 2,999 bhp.
Class 40
Class 41
Class 42
Class 43 (Warship)
Class 43 (HST)
Class 44
Class 45
Class 46
Class 47
Class 48
Class 50
Class 52
Class 53
Class 57
D0260 Lion (prototype)
DP2 (prototype)
Type 5
Locomotives classed as Type 5 produced 3,000 bhp or more.
Class 55
Class 56
Class 58
Class 59
Class 60
Class 66
Class 67
Class 68
Class 70
References
List of types
British Rail Power Classifications |
https://en.wikipedia.org/wiki/Spectrum%20bias | In biostatistics, spectrum bias refers to the phenomenon that the performance of a diagnostic test may vary in different clinical settings because each setting has a different mix of patients. Because the performance may be dependent on the mix of patients, performance at one clinic may not be predictive of performance at another clinic. These differences are interpreted as a kind of bias. Mathematically, the spectrum bias is a sampling bias and not a traditional statistical bias; this has led some authors to refer to the phenomenon as spectrum effects, whilst others maintain it is a bias if the true performance of the test differs from that which is 'expected'. Usually the performance of a diagnostic test is measured in terms of its sensitivity and specificity and it is changes in these that are considered when referring to spectrum bias. However, other performance measures such as the likelihood ratios may also be affected by spectrum bias.
Generally spectrum bias is considered to have three causes. The first is due to a change in the case-mix of those patients with the target disorder (disease) and this affects the sensitivity. The second is due to a change in the case-mix of those without the target disorder (disease-free) and this affects the specificity. The third is due to a change in the prevalence, and this affects both the sensitivity and specificity. This final cause is not widely appreciated, but there is mounting empirical evidence as well as theoretical argume |
https://en.wikipedia.org/wiki/CJTN-FM | CJTN-FM is a radio station in Trenton, Ontario, broadcasting on the assigned frequency of 107.1 MHz, serving Belleville and the Quinte region. Owned by Quinte Broadcasting, the station airs a classic rock music format branded as Rock 107.
History
The station began broadcasting at 1270 kHz on January 22, 1979, at a power of 1,000 watts, to service Trenton; hence the TN in the call sign. Ted Snider was the station's first manager. The original AM transmitter was located at Carrying Place, just south of Trenton. CJTN moved to its current frequency at 107.1 FM on August 16, 2004, and was branded as Lite 107 with an adult contemporary format. The station changed to a classic rock format on May 18, 2007 and was re-branded as Rock 107.
CJTN's weekday line-up consists of The Morning Buzz with Buzz Collins featuring Tim Durkin with news and Jack Miller with sports. Rick Kevan hosts afternoons. Special feature shows include The House of Hair with Dee Snider on Friday nights, The Acoustic Storm with Jeff Parets on Saturday mornings, Flashback with Max Pinfield on Saturday nights and Sunday mornings and weekend afternoons with Greg Moulton and Scott Hunter. In August 2019, veteran announcer Rick Kevan celebrated 40 years with Quinte Broadcasting.
CJTN's transmitter is located near Wooler Road and Highway 401, northwest of Trenton. Its signal is directional, to avoid co-channel interference to the west with CILQ-FM in Toronto.
References
External links
Rock 107
CJTN History - Canadia |
https://en.wikipedia.org/wiki/Kevin%20McCurley%20%28cryptographer%29 | Kevin Snow McCurley is a mathematician, computer scientist, and cryptographer, and a former research scientist at Google. He has written publications about information retrieval, algorithms, parallel computing, cryptography, and number theory.
Early life and education
When he was a child, McCurley had built model planes and cars, and he enjoyed making things with his hands.
McCurley attended a high school in San Jose, California. There, one of his teachers, Judy Jones, showed him that "mathematics really could be fun and interesting" and encouraged him to attend mathematical contests.
In his first year at Santa Clara University, McCurley had Jerry Anderson, a former president of the MAA, as his professor in calculus; Anderson told "interesting stories" and was able to "relate the mathematics to history and to activities that were meaningful". He started out as a mathematician, but he later retrained himself as a computer scientist.
In 1981, McCurley received his Ph.D. in mathematics from the University of Illinois at Urbana-Champaign. His dissertation in analytic number theory was titled Explicit Estimates for Functions of Primes in Arithmetic Progressions, and his advisor was Paul Trevier Bateman. He also received a master's in statistics there.
In the fall of 1995, McCurley taught an undergraduate course on cryptology at the University of New Mexico.
After he was a post-doc at Michigan State University, McCurley took a job at USC (Los Angeles), where he published som |
https://en.wikipedia.org/wiki/MYO7A | Myosin VIIA is protein that in humans is encoded by the MYO7A gene. Myosin VIIA is a member of the unconventional myosin superfamily of proteins. Myosins are actin binding molecular motors that use the enzymatic conversion of ATP - ADP + inorganic phosphate (Pi) to provide the energy for movement.
Myosins are mechanochemical proteins characterized by the presence of a motor domain, an actin-binding domain, a neck domain that interacts with other proteins, and a tail domain that serves as an anchor. Myosin VIIA is an unconventional myosin with the longest tail (1360 aa). The tail is expected to dimerize, resulting in a two-headed molecule. Unconventional myosins have diverse functions in eukaryotic cells and are primarily thought to be involved in the movement or linkage of intra-cellular membranes and organelles to the actin cytoskeleton via interactions mediated by their highly divergent tail domains.
MYO7A is expressed in a number of mammalian tissues, including testis, kidney, lung, inner ear, retina and the ciliated epithelium of the nasal mucosa.
Clinical significance
Mutations in the MYO7A gene cause the Usher syndrome type 1B, a combined deafness/blindness disorder. Affected individuals are typically profoundly deaf at birth and then undergo progressive retinal degeneration.
Model organisms
Model organisms have been used in the study of MYO7A function. A spontaneous mutant mouse line, called Myo7ash1-6J was generated. Male and female animals underwent a standardi |
https://en.wikipedia.org/wiki/Environmental%20enterprise | An environmental enterprise is an environmentally friendly/compatible business. Specifically, an environmental enterprise is a business that produces value in the same manner which an ecosystem does, neither producing waste nor consuming unsustainable resources. In addition, an environmental enterprise rather finds alternative ways to produce one's products instead of taking advantage of animals for the sake of human profits. To be closer to the goal of being an environmentally friendly company, some environmental enterprises invest their money to develop or improve their technologies which are also environmentally friendly. In addition, environmental enterprises usually try to reduce global warming, so some companies use materials that are environmentally friendly to build their stores. They also set in place regulations that are environmentally friendly. All these efforts of the environmental enterprises can bring positive effects both for nature and people. The concept is rooted in the well-enumerated theories of natural capital, the eco-economy and cradle to cradle design. Examples of environmental enterprise would be Seventh Generation, Inc., and Whole Foods.
Background
Economic globalization is an irreversible trend
Natural resource scarcity or/and abundance are drivers of globalization, as they incite supply and demand forces in global markets.
Environment and sustainability
For the past 50 years we have amassed unprecedented financial wealth, but have also chronica |
https://en.wikipedia.org/wiki/Key%20selection%20vector | A Key Selection Vector (KSV) is a numerical identifier associated with a Device Key Set which is distributed by a Licensor or its designee to Adopters and is used to support authentication of Licensed Products and Revocation as part of the HDCP copy protection system. The KSV is used to generate confidential keys, specifically used in the Restricted Authentication process of HDCP. Restricted Authentication is an AKE method for devices with limited computing resources. This method is used by copying devices of any kind (such as DV recorders or D-VHS recorders) and devices communicating with them for authenticating protected content. The restricted authentication protocol uses asymmetric key management and common key cryptography, and relies on the use of shared secrets and hash functions to respond to a random challenge.
Restricted Authentication Protocol
The goal of Restricted Authentication is for a device to prove that it holds a secret shared with other devices. One device authenticates another by issuing a random challenge for which the response is generated by combining the shared secrets and multiple hashes. Formally, a Key Selection Vector is a 40-bit vector containing 20 ones and 20 zeros, and is used to specify the random challenge. The Device Key Set is a collection of 40 56-bit values, and is the set of shared secrets for this protocol
During the authentication process, both parties (a transmitter and a receiver) exchange their KSVs. Then each device adds (unsign |
https://en.wikipedia.org/wiki/7-Aminoactinomycin%20D | 7-Aminoactinomycin D (7-AAD) is a fluorescent chemical compound with a strong affinity for DNA. It is used as a fluorescent marker for DNA in fluorescence microscopy and flow cytometry. It intercalates in double-stranded DNA, with a high affinity for GC-rich regions, making it useful for chromosome banding studies.
Applications
With an absorption maximum at 546 nm, 7-AAD is efficiently excited using a 543 nm helium–neon laser; it can also be excited with somewhat lower efficiency using a 488 nm or 514 nm argon laser lines. Its emission has a very large Stokes shift with a maximum in the deep red: 647 nm. 7-AAD is therefore compatible with most blue and green fluorophores – and even many red fluorophores – in multicolour applications.
7-AAD does not readily pass through intact cell membranes; if it is to be used as a stain for imaging DNA fluorescence, the cell membrane must be permeabilized or disrupted. This method can be used in combination with formaldehyde fixation of samples.
7-AAD is also used as a cell viability stain. Cells with compromised membranes will stain with 7-AAD, while live cells with intact cell membranes will remain dark. Viability of the cells in flow cytometry should be around 95% but not less than 90%.
Actinomycin D
The related compound actinomycin D is nonfluorescent, but binds DNA in the same way as 7-AAD. Its absorbance changes when bound to DNA, and it can be used as a stain in conventional transmission microscopy.
References
Gallery
|
https://en.wikipedia.org/wiki/Symmetric%20rank-one | The Symmetric Rank 1 (SR1) method is a quasi-Newton method to update the second derivative (Hessian)
based on the derivatives (gradients) calculated at two points. It is a generalization to the secant method for a multidimensional problem.
This update maintains the symmetry of the matrix but does not guarantee that the update be positive definite.
The sequence of Hessian approximations generated by the SR1 method converges to the true Hessian under mild conditions, in theory; in practice, the approximate Hessians generated by the SR1 method show faster progress towards the true Hessian than do popular alternatives (BFGS or DFP), in preliminary numerical experiments. The SR1 method has computational advantages for sparse or partially separable problems.
A twice continuously differentiable function has a gradient () and Hessian matrix : The function has an expansion as a Taylor series at , which can be truncated
;
its gradient has a Taylor-series approximation also
,
which is used to update . The above secant-equation need not have a unique solution .
The SR1 formula computes (via an update of rank 1) the symmetric solution that is closest to the current approximate-value :
,
where
.
The corresponding update to the approximate inverse-Hessian is
.
One might wonder why positive-definiteness is not preserved — after all, a rank-1 update of the form is positive-definite if is. The explanation is that the update might be of the form instead because the denominator can b |
https://en.wikipedia.org/wiki/Mark%20Burrier | Mark Burrier (born 6 May 1979) is an American cartoonist and illustrator.
Career
Burrier's style involves a fluid brush line and limited uses of color and texture. His works have been shown in galleries in New York City, Los Angeles, Tokyo, France, and Denmark. Burrier is also a skateboarder and has had his artwork appear on skateboards and apparel for Coda Skateboards. He has been independently self-publishing and distributing his comics for more than 10 years. His work has also been published internationally where it has appeared in various anthologies. SInce 2009, Burrier has been creating illustrations for Rare Words, which is one of his personal drawing blogs. Readers are able to submit words that later become works of art by Burrier. This has turned into a public sketchbook for Burrier.
Personal information
When Burrier was younger, he was heavily influenced by the independent music scene in the '80s and '90s. This is what inspired his artwork. Burrier and his wife currently live in Frederick, Maryland.
Appearances
Burrier's comics have been published internationally and have appeared in North American anthologies and magazines such as Kramers Ergot, The Drama, Studygroup12, and EXPO. Mark's illustrations have been shown in galleries in New York City, Los Angeles, Tokyo and Seattle. His comics and illustrations have received awards from Communication Arts, Print, American Illustration, HOW Magazine, STEP Inside Design and the American Advertising Federation.
Awards
|
https://en.wikipedia.org/wiki/Insulin-degrading%20enzyme | Insulin-degrading enzyme, also known as IDE, is an enzyme.
Known alternatively as insulysin or insulin protease, IDE is a large zinc-binding protease of the M16 metalloprotease family known to cleave multiple short polypeptides that vary considerably in sequence. Other members of this family include the mitochondrial processing peptidase and presequence protease.
Structure
Gene
The gene IDE encodes protein Insulin-degrading enzyme. The human gene IDE has 28 exons and is located at chromosome band 10q23-q25.
Protein
Due to alternative splicing, The human protein Insulin-degrading Enzyme has two isoforms. Isoform1 is ~118 kDa in size and composed of 1019 amino acids while the isoform 2 is ~54.2 kDa size and composed of 464 amino acids (missing 1-555 amino acids). The calculated theoretical pI of this protein isoform is 6.26.
Structural studies of IDE by Shen et al. have provided insight into the functional mechanisms of the protease. Reminiscent of the previously determined structure of the bacterial protease pitrilysin, the IDE crystal structure reveals defined N and C terminal units that form a proteolytic chamber containing the zinc-binding active site. In addition, it appears that IDE can exist in two conformations: an open conformation, in which substrates can access the active site, and a closed state, in which the active site is contained within the chamber formed by the two concave domains. Targeted mutations that favor the open conformation result in a 40-fold |
https://en.wikipedia.org/wiki/KCNE2 | Potassium voltage-gated channel subfamily E member 2 (KCNE2), also known as MinK-related peptide 1 (MiRP1), is a protein that in humans is encoded by the KCNE2 gene on chromosome 21. MiRP1 is a voltage-gated potassium channel accessory subunit (beta subunit) associated with Long QT syndrome. It is ubiquitously expressed in many tissues and cell types. Because of this and its ability to regulate multiple different ion channels, KCNE2 exerts considerable influence on a number of cell types and tissues. Human KCNE2 is a member of the five-strong family of human KCNE genes. KCNE proteins contain a single membrane-spanning region, extracellular N-terminal and intracellular C-terminal. KCNE proteins have been widely studied for their roles in the heart and in genetic predisposition to inherited cardiac arrhythmias. The KCNE2 gene also contains one of 27 SNPs associated with increased risk of coronary artery disease. More recently, roles for KCNE proteins in a variety of non-cardiac tissues have also been explored.
Discovery
Steve Goldstein (then at Yale University) used a BLAST search strategy, focusing on KCNE1 sequence stretches known to be important for function, to identify related expressed sequence tags (ESTs) in the NCBI database. Using sequences from these ESTs, KCNE2, 3 and 4 were cloned.
Tissue distribution
KCNE2 protein is most readily detected in the choroid plexus epithelium, gastric parietal cells, and thyroid epithelial cells. KCNE2 is also expressed in atrial |
https://en.wikipedia.org/wiki/SCN4B | Sodium channel β-subunit 4, also known as SCN4B or Naβ4, is an auxiliary sodium channel subunit that can alter the kinetics of sodium channels. The protein is encoded by the SCN4B gene. Mutations in the SCN4B are associated with long QT syndrome.
SCN4B might additionally function as a cell adhesion molecule.
See also
Sodium channel
References
External links
Sodium channels |
https://en.wikipedia.org/wiki/RpoF | The gene rpoF (RNA polymerase, flagellum F) encodes the sigma factor sigma-28 (σ28, or RpoF), a protein in Escherichia coli and other species of bacteria. Depending on the bacterial species, this gene may be referred to as sigD or fliA. The protein encoded by this gene has been found to be necessary for flagellum formation.
References
Escherichia coli genes |
https://en.wikipedia.org/wiki/MB-3%20%28drug%29 | MB-3 is a drug which acts as a potent and selective inhibitor of the histone acetyltransferase enzyme GCN5, which usually functions as a negative modulator of PGC-1α, and so MB-3 acts to indirectly activate PGC-1α. It is used in research into the role of the GCN5/PGC-1α pathway in the regulation of metabolism and cell differentiation.
See also
HY-124798
References
Enzyme inhibitors
Vinylidene compounds |
https://en.wikipedia.org/wiki/Artie%20Owens | Arthur Gene Owens (born January 14, 1953) was an American football running back, return specialist, and receiver that played collegiately for the West Virginia Mountaineers. He was also a track runner for the Mountaineers. Owens was primarily known for playing in the National Football League (NFL) and also in the United States Football League (USFL).
High school career
Artie Owens moved from Alabama to Pennsylvania as a youth. As a senior, Owens led the Stroudsburg High School Mountaineers to an 11-0 record and established Pennsylvania records for touchdowns, with 41, and yards rushing, with 2,061. He was named a Kodak All-American, UPI and AP all-state, all-Big 33, all-Lehigh Valley and all-Eastern Pennsylvania for Coach Fred Ross. Owens also was on the Mounties' basketball and track teams, and once ran the 100-yard dash in 9.8 seconds.
College career
Football
Artie Owens arrived at West Virginia in 1972. Owens saw limited time as a freshman, only rushing for 72 yards and one touchdown. He also had 369 return yards, along with an 85-yard kick return.
As a sophomore in 1973, Owens was the projected starter at the beginning of the season. But an injury led to newcomer Dwayne Woods to assume to role for the rest of the season. Owens only rushed for 391 yards and 3 touchdowns, but he did have 291 return yards with a kick return touchdown of 95 yards against Penn State. His sophomore season marked his final season of returning punts.
In his junior season of 1974, Owens went |
https://en.wikipedia.org/wiki/Resonance%20fluorescence | Resonance fluorescence is the process in which a two-level atom system interacts with the quantum electromagnetic field if the field is driven at a frequency near to the natural frequency of the atom.
General theory
Typically the photon contained electromagnetic field is applied to the two-level atom through the use of a monochromatic laser. A two-level atom is a specific type of two-state system in which the atom can be found in the two possible states. The two possible states are if an electron is found in its ground state or the excited state. In many experiments an atom of lithium is used because it can be closely modeled to a two-level atom as the excited states of the singular electron are separated by large enough energy gaps to significantly reduce the possibility of the electron jumping to a higher excited state. Thus it allows for easier frequency tuning of the applied laser as frequencies further off resonance can be used while still driving the electron to jump to only the first excited state. Once the atom is excited, it will release a photon with the same energy as the energy difference between the excited and ground state. The mechanism for this release is the spontaneous decay of the atom. The emitted photon is released in an arbitrary direction. While the transition between two specific energy levels is the dominant mechanism in resonance fluorescence, experimentally other transitions will play a very small role and thus must be taken into account when analy |
https://en.wikipedia.org/wiki/Davidon%E2%80%93Fletcher%E2%80%93Powell%20formula | The Davidon–Fletcher–Powell formula (or DFP; named after William C. Davidon, Roger Fletcher, and Michael J. D. Powell) finds the solution to the secant equation that is closest to the current estimate and satisfies the curvature condition. It was the first quasi-Newton method to generalize the secant method to a multidimensional problem. This update maintains the symmetry and positive definiteness of the Hessian matrix.
Given a function , its gradient (), and positive-definite Hessian matrix , the Taylor series is
and the Taylor series of the gradient itself (secant equation)
is used to update .
The DFP formula finds a solution that is symmetric, positive-definite and closest to the current approximate value of :
where
and is a symmetric and positive-definite matrix.
The corresponding update to the inverse Hessian approximation is given by
is assumed to be positive-definite, and the vectors and must satisfy the curvature condition
The DFP formula is quite effective, but it was soon superseded by the Broyden–Fletcher–Goldfarb–Shanno formula, which is its dual (interchanging the roles of y and s).
See also
Newton's method
Newton's method in optimization
Quasi-Newton method
Broyden–Fletcher–Goldfarb–Shanno (BFGS) method
Limited-memory BFGS method
Symmetric rank-one formula
Nelder–Mead method
References
Further reading
Optimization algorithms and methods |
https://en.wikipedia.org/wiki/Germany%20Billie%20Jean%20King%20Cup%20team | The Germany women's national tennis team represents Germany in Billie Jean King Cup tennis competition and are governed by Deutscher Tennis Bund.
Current team
Statistics correct as of 16 October 2023.
History
Germany competed in its first Fed Cup in 1963. They won the Cup in 1987 and 1992, and finished as runners-up five times.
Finals
Players
Player records
Results
1963–1969
1970–1979
1980–1989
1990–1999
2000–2009
2010–2019
2020–
See also
Billie Jean King Cup
Tennis in Germany
Germany Davis Cup team
Germany at the Hopman Cup
External links
Billie Jean King Cup teams
Fed Cup |
https://en.wikipedia.org/wiki/Population%20vector | In neuroscience, a population vector is the sum of the preferred directions of a population of neurons, weighted by the respective spike counts.
The formula for computing the (normalized) population vector, , takes the following form:
Where is the activity of cell , and is the preferred input for cell .
Note that the vector encodes the input direction, , in terms of the activation of a population of neurons.
Computational neuroscience |
https://en.wikipedia.org/wiki/Scree%20plot | In multivariate statistics, a scree plot is a line plot of the eigenvalues of factors or principal components in an analysis. The scree plot is used to determine the number of factors to retain in an exploratory factor analysis (FA) or principal components to keep in a principal component analysis (PCA). The procedure of finding statistically significant factors or components using a scree plot is also known as a scree test. Raymond B. Cattell introduced the scree plot in 1966.
A scree plot always displays the eigenvalues in a downward curve, ordering the eigenvalues from largest to smallest. According to the scree test, the "elbow" of the graph where the eigenvalues seem to level off is found and factors or components to the left of this point should be retained as significant.
Etymology
The scree plot is named after the elbow's resemblance to a scree in nature.
Criticism
This test is sometimes criticized for its subjectivity. Scree plots can have multiple "elbows" that make it difficult to know the correct number of factors or components to retain, making the test unreliable. There is also no standard for the scaling of the and axes, which means that different statistical programs can produce different plots from the same data.
The test has also been criticized for producing too few factors or components for factor retention.
As the "elbow" point has been defined as point of maximum curvature, as maximum curvature captures the leveling off effect operators use to id |
https://en.wikipedia.org/wiki/Yellow%20cab%20%28stereotype%29 | is a disparaging term for Japanese women who travel overseas or to foreign enclaves in Japan seeking to meet foreign men.
The term combines the use of "yellow", a color/racial classification category for people of East Asian origin, and the image of a yellow cab which can be "ridden at any time".
The term was spread to Japan by Shōko Ieda's 1991 book Yellow Cab, and was quickly appropriated by the Japanese media as a way of sensationalizing and censuring the women's behaviour. Later, Yellow Cab was exposed as a fraud, and Japanese media reports were criticized.
Social context
Women described as "yellow cabs" can often be observed in so-called "border regions" consisting of highly transient, ethnically and culturally mixed populations. One scholar studying the "yellow cab" phenomenon listed the Roppongi district of Tokyo, United States Forces Japan bases in locations such as Yokosuka, Yokota, Misawa, Iwakuni, Sasebo, and Okinawa as possible locations in Japan, and Hawaii, New York City, and the West Coast in the United States.
Sources disagree as to the question of power in these relationships. One argument analyses the phenomenon in terms of consumer patterns: the women are in the financially superior position due to the strength of the Japanese yen and their own disposable income, and are using their power to purchase sex; one such woman even described her foreign boyfriends as "pets". The opposing argument puts the phenomenon in the context of a larger "romantici |
https://en.wikipedia.org/wiki/Mesothelin | Mesothelin, also known as MSLN, is a protein that in humans is encoded by the MSLN gene.
Function
Mesothelin is a 40 kDa protein that is expressed in mesothelial cells. The protein was first identified by its reactivity with monoclonal antibody K1. Subsequent cloning studies showed that the mesothelin gene encodes a precursor protein that is processed to yield mesothelin which is attached to the cell membrane by a glycophosphatidylinositol linkage and a 31-kDa shed fragment named megakaryocyte-potentiating factor (MPF). Although it has been proposed that mesothelin may be involved in cell adhesion, its biological function is not known. A knockout mouse line that lacks mesothelin reproduces and develops normally.
Mesothelin is over expressed in several human tumors, including mesothelioma, ovarian cancer, pancreatic adenocarcinoma, lung adenocarcinoma, and cholangiocarcinoma. Mesothelin binds MUC16 (also known as CA125), indicating that the interaction of mesothelin and MUC16 may contribute to the implantation and peritoneal spread of tumors by cell adhesion. The region (residues 296-359) consisting of 64 amino acids at the N-terminus of cell surface mesothelin has been identified as the functional binding domain (named IAB) for MUC16/CA125, suggesting the mechanism of mesothelin acting as a MUC16/CA125 functional partner in cancer development.
Medical applications
Mesothelin is a tumor differentiation antigen that is normally present on the mesothelial cells lining th |
https://en.wikipedia.org/wiki/Jo-ha-ky%C5%AB | is a concept of modulation and movement applied in a wide variety of traditional Japanese arts. Roughly translated to "beginning, break, rapid", it essentially means that all actions or efforts should begin slowly, speed up, and then end swiftly. This concept is applied to elements of the Japanese tea ceremony, martial arts (kenjutsu, iaido, kendō, karate), dramatic structure in the traditional theatre, and to the traditional collaborative linked verse forms renga and renku (haikai no renga).
The concept originated in gagaku court music, specifically in the ways in which elements of the music could be distinguished and described. Though eventually incorporated into a number of disciplines, it was most famously adapted, and thoroughly analysed and discussed by the great Noh playwright Zeami, who viewed it as a universal concept applying to the patterns of movement of all things.
Theatre
It is perhaps in the theatre that jo-ha-kyū is used the most extensively, on the most levels. Following the writings of Zeami, all major forms of Japanese traditional drama (Noh, kabuki, and jōruri) utilize the concept of jo-ha-kyū, from the choice and arrangement of plays across a day, to the composition and pacing of acts within a play, down to the individual actions of the actors.
Zeami, in his work "Sandō" (The Three Paths), originally described a five-part (five dan) Noh play as the ideal form. It begins slowly and auspiciously in the first part (jo), building up the drama and tension i |
https://en.wikipedia.org/wiki/Jean%20Forestier | Jean Forestier (born 7 October 1930) is a French former cyclist. He was a professional from 1953 to 1965. Forestier won the points classification in the 1957 Tour de France, and wore the yellow jersey for two days. He also won the 1955 Paris–Roubaix.
Major results
Source:
1953
1st GP de Thizy
9th Overall Circuit des Six Provinces
1st Stage 1
1954
1st Overall Tour de Romandie
1st Stage 16 Tour de France
1st GP de Thizy
1955
1st Paris–Roubaix
1st GP de Cannes
1st Stage 20 Tour de France
10th Overall Tour du Sud-Est
1st Stage 2
1956
1st Tour of Flanders
1st Stage 16 Tour de France
1957
1st Overall Tour de Romandie
1st Stages 2 & 3b
1st Overall Critérium National
1st Stage 8 Critérium du Dauphiné Libéré
4th Overall Tour de France
1st Points classification
1958
1st Stage 7a Critérium du Dauphiné Libéré
1961
1st Grand Prix du Parisien
1st Stage 8 Tour de France
References
Bibliography
External links
French male cyclists
French Tour de France stage winners
1930 births
Living people
Cyclists from Lyon |
https://en.wikipedia.org/wiki/Genome%20survey%20sequence | In the fields of bioinformatics and computational biology, Genome survey sequences (GSS) are nucleotide sequences similar to expressed sequence tags (ESTs) that the only difference is that most of them are genomic in origin, rather than mRNA.
Genome survey sequences are typically generated and submitted to NCBI by labs performing genome sequencing and are used, amongst other things, as a framework for the mapping and sequencing of genome size pieces included in the standard GenBank divisions.
Contributions
Genome survey sequencing is a new way to map the genome sequences since it is not dependent on mRNA. Current genome sequencing approaches are mostly high-throughput shotgun methods, and GSS is often used on the first step of sequencing. GSSs can provide an initial global view of a genome, which includes both coding and non-coding DNA and contain repetitive section of the genome unlike ESTs. For the estimation of repetitive sequences, GSS plays an important role in the early assessment of a sequencing project since these data can affect the assessment of sequences coverage, library quality and the construction process. For example, in the estimation of dog genome, it can estimate the global parameters, such as neutral mutation rate and repeat content.
GSS is also an effective way to large-scale and rapidly characterizing genomes of related species where there is only little gene sequences or maps. GSS with low coverage can generate abundant information of gene content and |
https://en.wikipedia.org/wiki/List%20of%20whitewater%20rivers | A whitewater river is any river where its gradient and/or flow create rapids or whitewater turbulence. This list only focuses on rivers which are suitable for whitewater sports such as canoeing, kayaking, and rafting.
Africa
Zambezi, Zambia
Nile, Uganda
Tana River, Kenya
Asia
Pakistan
Sutlej
Braldu
Swat
Kunhar River
Indus River
Thailand
Wa River is a popular whitewater rafting destination in the Nan Province of Thailand. It has rapids ranging from difficulty levels of 2 through 6.
Wang Thong River is a popular whitewater rafting destination in the Phitsanulok Province of Thailand. It has rapids ranging from difficulty levels of 3 through 5.
India
In the north, most rivers in India descend from the Himalayas, the highest mountains on earth: cold glacial waters thunder down the rocks, bringing with them ample whitewater rapids to encounter. The water here is high volume and can be very violent in the early spring. Hence, extreme caution must be taken if one has not mastered paddling skills for rapids above class III. Caution should otherwise be exercised near the Tibetan border as this is area is a place of extreme political dispute, on land and on water.
Zanskar, a Grand Canyonesque experience. Class III-IV. Gradings, as on all rivers, subject to change depending on volume of water.
Alaknanda
Bhagirathi
Brahmaputra River- This river begins in Tibet and winds its way towards Arunachal Pradesh, from whence it continues in a very steep gradient. Class V |
https://en.wikipedia.org/wiki/GCD%20test | In compiler theory, a greatest common divisor test (GCD test) is the test used in study of loop optimization and loop dependence analysis to test the dependency between loop statements.
Description
A greatest common divisor (GCD) test is a test used in computer science compiler theory to study of loop optimization and loop dependence analysis to test the dependency between loop statements.
Use
Whenever a sequential loop like for loop is made to be parallel so that it can be executed on more than one processor—as in case of grid computing or cluster computing—then certain dependencies (e.g., testing the flow (true) dependence of a statement) are checked to know whether the loop can be parallelized. According to this test, by comparing the indices of two arrays present in two or more statements, it can be calculated whether it is legal to parallelize the loop or not.
Rationale
Theorem
A linear Diophantine equation
a1*x1 + a2*x2 +... + an*xn =c
has an integer solution x1, x2,..., xn iff GCD (a1,a2,.., an) divides c.
E.g.
2*x1 -2*x2 =1
GCD(2,-2) =2, 2 cannot divide 1. So, there is no integer solution for the equation above.
Dependency analysis
It is difficult to analyze array references in compile time to determine data dependency (whether they point to same address or not). A simple and sufficient test for the absence of a dependence is the greatest common divisor (GCD) test. It is based on the observation that if a loop carried dependency exists between X[a*i |
https://en.wikipedia.org/wiki/Ikanos%20Communications | Ikanos Communications, Incorporated, was a provider of semiconductor and software products for use in homes. It was headquartered in Fremont, California. The company’s digital subscriber line, communications processors and other products were used in customer premises equipment from network equipment manufacturers and telecommunications service providers.
History
On December 10, 2001, the founder and chief technology officer of Ikanos, Behrooz Rezvani, announced he was editor of the Institute of Electrical and Electronics Engineers (IEEE) draft standard for Ethernet in the first mile over copper.
On August 24, 2009 Ikanos acquired Conexant's Broadband Access product line for about $54 million in cash. It also announced an investment of $42 million from Tallwood Venture Capital.
In June 2010, John Quigley replaced Michael Gulett as chief executive (who left in April). He was the fifth CEO in six years.
A U.S. appeals court on May 25, 2012 revived a shareholder lawsuit accusing Ikanos of failing to properly disclose known defects in its semiconductor chips at the time it was conducting a 2006 stock offering.
In August 2015, Ikanos was acquired by Qualcomm Atheros in a deal worth around $47 million, with Qualcomm taking on $20 million of liabilities from Ikanos.
In August 2016 Qualcomm Atheros has closed its recently acquired Ikanos operations.
References
Telecommunications companies established in 1999
Digital subscriber line
Electronics companies of the United States
|
https://en.wikipedia.org/wiki/Jerry%20Murphy | Jeremiah Michael Murphy (born 23 September 1959) is a retired professional footballer who played as a midfielder in the League for Crystal Palace and Chelsea before moving into non-league football with Fisher Athletic. Born in England, he made three appearances for the Republic of Ireland national team.
Career
Murphy started out with Terry Venables' Crystal Palace, spending nine years at Selhurst Park during which time he won the FA Youth Cup in both 1977 and 1978 as part of the famous "Team of the Eighties". The club were then promoted to the First Division in Murphy's first full season in the side, but were relegated after two seasons in the top flight. However, Murphy remained with Palace winning the "Player of the Year" award in 1983.
He moved back to the top flight again, joining Chelsea on a free transfer in the summer of 1985.
He scored in a 1–1 draw at Everton which put Chelsea briefly top of the league. The daily mirror's back page headline the next day was "Jerry and the Pacemakers". His time at Stamford Bridge was affected by lack of form and injury problems. In three seasons he made only 34 league appearances and his contract was cancelled due to injury in March 1988. He joined non-league side Fisher Athletic to finish his career.
See also
List of Republic of Ireland international footballers born outside the Republic of Ireland
References
External links
1959 births
Living people
Republic of Ireland men's association footballers
English men's footballe |
https://en.wikipedia.org/wiki/Protein%20adulteration%20in%20China | In China, the adulteration and contamination of several food and feed ingredients with inexpensive melamine and other compounds, such as cyanuric acid, ammeline and ammelide, are common practice. These adulterants can be used to inflate the apparent protein content of products, so that inexpensive ingredients can pass for more expensive, concentrated proteins. Melamine by itself has not been thought to be very toxic to animals or humans except possibly in very high concentrations, but the combination of melamine and cyanuric acid has been implicated in kidney failure. Reports that cyanuric acid may be an independently and potentially widely used adulterant in China have heightened concerns for both animal and human health.
Chinese protein export contamination was first identified after the wide recall of many brands of cat and dog food starting in March 2007 (the 2007 pet food recalls). The recalls in North America, Europe and South Africa came in response to reports of kidney failure in pets. Several Chinese companies sold products claimed to be wheat gluten, rice protein or corn gluten, but which proved to be wheat flour adulterated with melamine, cyanuric acid, and other contaminants. The Chinese government was slow to respond, denying that vegetable protein was exported from China and refusing to allow foreign food safety investigators to enter the country. Ultimately, the Chinese government acknowledged that contamination had occurred and arrested the managers of two |
https://en.wikipedia.org/wiki/Quantum%20master%20equation | A quantum master equation is a generalization of the idea of a master equation. Rather than just a system of differential equations for a set of probabilities (which only constitutes the diagonal elements of a density matrix), quantum master equations are differential equations for the entire density matrix, including off-diagonal elements. A density matrix with only diagonal elements can be modeled as a classical random process, therefore such an "ordinary" master equation is considered classical. Off-diagonal elements represent quantum coherence which is a physical characteristic that is intrinsically quantum mechanical.
A formally exact quantum master equation is the Nakajima–Zwanzig equation, which is in general as difficult to solve as the full quantum problem.
The Redfield equation and Lindblad equation are examples of approximate Markovian quantum master equations. These equations are very easy to solve, but are not generally accurate.
Some modern approximations based on quantum master equations, which show better agreement with exact numerical calculations in some cases, include the polaron transformed quantum master equation and the VPQME (variational polaron transformed quantum master equation).
Numerically exact approaches to the kinds of problems to which master equations are usually applied include numerical Feynman integrals, quantum Monte Carlo, DMRG and NRG, MCTDH, and HEOM.
See also
Open quantum system
Quantum dynamics
Quantum coherence
Differential equa |
https://en.wikipedia.org/wiki/International%20Red%20Cross%20Wound%20Classification%20System | The International Red Cross wound classification system is a system whereby certain features of a wound are scored: the size of the skin wound(s); whether there is a cavity, fracture or vital structure injured; the presence or absence of metallic foreign bodies. A numerical value is given to each feature (E, X, C, F, V, and M). The scores can later be graded according to severity and typed according to the structures injured.
This scoring system is intended for quick and easy use in the field.
Wounds are scored after surgery or initial assessment.
E = (Entry) centimetres. Estimate the maximum diameter of the entry.
X = (eXit) centimetres. Estimate the maximum diameter of the exit (X = 0 if no exit).
C = (Cavity) Can the "cavity" of the wound take 2 fingers before surgery? No: C=0, Yes: C=1.
This may be obvious before operation or only established after skin incision. For chest and abdominal wounds it refers to the wound of the chest or abdominal wall.
F = (Fracture) No fracture: F=0. Simple fracture, hole or insignificant comminution: F=1. Clinically significant comminution: F=2.
V = (Vital structure) Are brain, viscera (breach of dura, pleura or peritoneum) or major vessels injured? No: V=0. Yes: V=1.
M = (Metallic body) Bullet or fragments visible on X-ray. None: M=0. One metallic body: M=1. Multiple metallic bodies: M=2.
The wound classification system has been criticised on the basis that "it fails to account for the synergistic effect of combined arms employmen |
https://en.wikipedia.org/wiki/Small%20nucleolar%20RNA%20U3 | In molecular biology, U3 snoRNA is a non-coding RNA found predominantly in the nucleolus.
U3 has C/D box motifs that technically make it a member of the box C/D class of snoRNAs; however, unlike other C/D box snoRNAs, it has not been shown to direct 2'-O-methylation of other RNAs.
Rather, U3 is thought to guide site-specific cleavage of ribosomal RNA (rRNA) during pre-rRNA processing.
The box C/D element is a subset of the six short sequence elements found in all U3 snoRNAs, namely boxes A, A', B, C, C', and D. The U3 snoRNA secondary structure is characterized by a small 5' domain (with boxes A and A'), and a larger 3' domain (with boxes B, C, C', and D), the two domains being linked by a single-stranded hinge. Boxes B and C form the B/C motif, which appears to be exclusive to U3 snoRNAs, and boxes C' and D form the C'/D motif. The latter is functionally similar to the C/D motifs found in other snoRNAs. The 5' domain and the hinge region act as a pre-rRNA-binding domain. The 3' domain has conserved protein-binding sites. Both the box B/C and box C'/D motifs are sufficient for nuclear retention of U3 snoRNA. The box C'/D motif is also necessary for nucleolar localization, stability and hyper-methylation of U3 snoRNA. Both box B/C and C'/D motifs are involved in specific protein interactions and are necessary for the rRNA processing functions of U3 snoRNA.
Species-specific secondary structure models
S. cerevisiae secondary structure determined by chemical mapping of U3A RNA |
https://en.wikipedia.org/wiki/The%20Hungry%20Gene | The Hungry Gene is a 2002 book by Ellen Ruppel Shell in which she tackles the issue of obesity. It is a non-fiction journalistic book. The author devotes multiple chapters of her book to the events that led to the co-discovery of the Leptin gene in 1994. Based on interviews with the parties involved, she reports that Leptin was co-discovered at Rockefeller University by Rudolph Leibel, Jeffrey Friedman, and members of their laboratories, and explains why Leibel and others were excluded by Friedman in the scientific paper that announced the discovery.
References
External links
"The Hungry Gene", book preview, Google Books
American non-fiction books
Books about health |
https://en.wikipedia.org/wiki/Pepscan | Pepscan is a procedure for mapping and characterizing epitopes involving the synthesis of overlapping peptides and analysis of the peptides in enzyme-linked immunosorbent assays (ELISAs). The method is based on combinatorial chemistry and was pioneered by Mario Geysen and coworkers.
Rob Meloen was one of Geysen's co-workers. He also played an important role in the development of numerous other new technologies, including vaccine and diagnostic product development for several viral diseases. From 1994 to 2010, Meloen was Professor of Special Appointment (Chair: Biomolecular Recognition) at Utrecht University. He was one of the co-founders of the company Pepscan (Lelystad, the Netherlands) and became Scientific Director (CSO). Pepscan is now part of the Biosynth Group.
Twenty-five years later, the Pepscan methodology, evolved and modernized with the latest insights, is still an important part of Pepscan’s epitope mapping platform, which is instrumental in therapeutic antibody development.
References
Biochemistry methods
Peptides
Immunology |
https://en.wikipedia.org/wiki/6S%20/%20SsrS%20RNA | In the field of molecular biology the 6S RNA is a non-coding RNA that was one of the first to be identified and sequenced. What it does in the bacterial cell was unknown until recently. In the early 2000s scientists found out the function of 6S RNA to be as a regulator of sigma 70-dependent gene transcription. All bacterial RNA polymerases have a subunit called a sigma factor. The sigma factors are important because they control how DNA promoter binding and RNA transcription start sites. Sigma 70 was the first one to be discovered in Escherichia coli.
Structure
The structure of 6S RNA was defined in 1971. It is a small RNA strand consisting of 184 nucleotides. 6S RNA is a long double-stranded structure and has a single strand loop. The structure is similar to an open promoter complex of DNA structure. Various analyses discovered that 6S RNAs are capable of forming a secondary structure. The secondary structure consists of two irregular helical stem regions, making a large core loop which is called a central knot.
Function and Regulation
The function of 6S RNA is to regulate transcription for E. coli cell survival because it is essential in the process. 6S RNA specifically associates with RNA polymerase holoenzyme containing the sigma70 specificity factor. This interaction represses expression from sigma70-dependent promoters during stationary phase. Which will lead to activate the transcription from sigma 70 dependent promoters. Therefore, during the change in E. coli fr |
https://en.wikipedia.org/wiki/Small%20nucleolar%20RNA%20SNORD14 | In molecular biology, U14 small nucleolar RNA (U14 snoRNA) is a non-coding RNA required for early cleavages of eukaryotic precursor rRNAs. In yeasts, this molecule possesses a stem-loop region (known as the Y-domain) which is essential for function. A similar structure, but with a different consensus sequence, is found in plants, but is absent in vertebrates. In human there are two closely related copies called SNORD14A and SNORD14B that are expressed from the intron of their host gene ribosomal protein Rps13.
References
External links
Entry for SNORD14A in HGNC database
Entry for SNORD14B in HGNC database
Small nuclear RNA |
https://en.wikipedia.org/wiki/Y%20RNA | Y RNAs are small non-coding RNAs. They are components of the Ro60 ribonucleoprotein particle which is a target of autoimmune antibodies in patients with systemic lupus erythematosus. They are also reported to be necessary for DNA replication through interactions with chromatin and initiation proteins. However, mouse embryonic stem cells lacking Y RNAs are viable and have normal cell cycles.
Structure
These small RNAs are predicted to fold into a conserved stem formed by the RNA's 3′ and 5′ ends and characterized by a single bulged cytosine, which are the known requirements for Ro binding.
Function
Two functions have been described for Y RNAs in the literature: As a repressor of Ro60, and as an initiation factor for DNA replication. Mutant human Y RNAs lacking the conserved binding site for Ro60 protein still support DNA replication, indicating that binding to Ro protein and promoting DNA replication are two separable functions of Y RNAs. Although Y RNA-derived small RNAs are similar in size to microRNAs, it has been shown that these Y RNA fragments are not involved in the microRNA pathway.
Ro60 Inhibition
In its free state, Ro binds to a variety of misfolded RNAs including misfolded 5S rRNAs, and is thought to act as some sort of quality control mechanism. Crystal structures of Ro complexed either with Y RNA or another RNA showed that Ro binds single-stranded 3′ ends of RNAs relatively nonspecifically, whereas Y RNA binds specifically at a second site that regulates acce |
https://en.wikipedia.org/wiki/RNase%20MRP | RNase MRP (also called RMRP) is an enzymatically active ribonucleoprotein with two distinct roles in eukaryotes. RNAse MRP stands for RNAse for mitochondrial RNA processing. In mitochondria it plays a direct role in the initiation of mitochondrial DNA replication. In the nucleus it is involved in precursor rRNA processing, where it cleaves the internal transcribed spacer 1 between 18S and 5.8S rRNAs. Despite distinct functions, RNase MRP has been shown to be evolutionarily related to RNase P. Like eukaryotic RNase P, RNase MRP is not catalytically active without associated protein subunits.
Mutations in the RNA component of RNase MRP cause cartilage–hair hypoplasia, a pleiotropic human disease. Responsible for this disease is a mutation in the RNase MRP RNA gene (RMRP), a non-coding RNA gene. RMRP was the first non-coding nuclear RNA gene found to cause disease.
Mechanism and mutation effects
RNase MRP and its role in pre-rRNA processing has been previously studied in Yeast cells. RNase MRP has been shown to cleave an internal transcribed spacer, specifically ITS1 at the specific site A3 of the rRNA precursor, leading, after additional trimming, to the formation of the mature 5′-end of 5.8S rRNA.
Recent data that has been gathered using several temperature-sensitive RNase MRP mutants that showed that inactivation of RNase MRP leading to severe reduction of the abundance of all early intermediates in the typical rRNA processing pathway. However, the transcription of the r |
https://en.wikipedia.org/wiki/Hairpin%20ribozyme | The hairpin ribozyme is a small section of RNA that can act as a ribozyme. Like the hammerhead ribozyme it is found in RNA satellites of plant viruses. It was first identified in the minus strand of the tobacco ringspot virus (TRSV) satellite RNA where it catalyzes self-cleavage and joining (ligation) reactions to process the products of rolling circle virus replication into linear and circular satellite RNA molecules. The hairpin ribozyme is similar to the hammerhead ribozyme in that it does not require a metal ion for the reaction.
Biological function
The hairpin ribozyme is an RNA motif that catalyzes RNA processing reactions essential for replication of the satellite RNA molecules in which it is embedded. These reactions are self-processing, i.e. a molecule rearranging its own structure. Both cleavage and end joining reactions are mediated by the ribozyme motif, leading to a mixture of interconvertible linear and circular satellite RNA molecules. These reactions are important for processing the large multimeric RNA molecules that are generated by rolling circle replication. At the end of the replication cycle, these large intermediates of satellite RNA replication are processed down to unit length molecules (circular or linear) before they can be packaged by viruses and carried to other cells for further rounds of replication.
Natural versions of the hairpin ribozyme
In the 1980s, the hairpin ribozyme was identified in 3 naturally occurring and well-characterized seq |
https://en.wikipedia.org/wiki/Cobalamin%20riboswitch | Cobalamin riboswitch is a cis-regulatory element which is widely distributed in 5' untranslated regions of vitamin B12 (Cobalamin) related genes in bacteria.
Cobalamin (vitamin B12, coenzyme B12 ) riboswitches are structured RNA elements that regulate adjacent genes related to cobalamin metabolism in response to cobalamin binding. Riboswitches are RNA-based genetic regulatory elements present in the 5’ untranslated region (5'UTR) of primarily bacterial RNA. These switches bind to a ligand, which is generally a metabolite, with high affinity and specificity. Ligand binding mediates allosteric rearrangement of mRNA structure, and this results in modulation of gene expression or translation of mRNA to yield a protein. The cobalamin riboswitch, along with most other riboswitches, are cis-regulatory. This means they regulate genes involved in the same metabolic pathways as the metabolite they bind, which creates regulation through a negative feedback loop. Riboswitches are grouped into classes by the ligand that they bind because the ligand-binding or aptamer domain is highly conserved across species. Riboswitches, including the cobalamin riboswitch, have garnered a lot of attention recently due to their therapeutic and synthetic potential, as well as their interesting structural properties. As of 2019, cobalamin riboswitches have been identified in over 5000 species of bacteria.
Ligand selectivity
Cobalamin riboswitches bind cobalamin (vitamin B12), which is a complex enzyme |
https://en.wikipedia.org/wiki/Tryptophan%20operon%20leader | The Tryptophan operon leader is an RNA element found at the 5′ of some bacterial tryptophan operons. The leader sequence can form two different structures known as the terminator and the anti-terminator, based on the Tryptophan amounts in the cell. The leader also codes for very short peptide sequence that is rich in tryptophan. The terminator structure is recognised as a termination signal for RNA polymerase and the operon is not transcribed. This structure forms when the cell has an excess of tryptophan and ribosome movement over the leader transcript is not impeded. When there is a deficiency of the charged tryptophanyl tRNA the ribosome translating the leader peptide stalls and the antiterminator structure can form. This allows RNA polymerase to transcribe the operon.
At least 6 different amino acid operons are known to be regulated by this attenuation.
Trp RNA-binding attenuation protein
The formation of the terminator requires the trp RNA-binding attenuation protein (TRAP protein) in species of Bacillus and related bacteria. This protein is encoded by the MtrB gene. TRAP protein forms an oligomer of 11 subunits, in the presence of tryptophan this binds to section of RNA containing 11 (G/U)AG repeats. This sequence overlaps the anti-terminator loop, thus TRAP-binding preventing formation of the anti-terminator loop. When TRAP is bound the terminator loop forms and the operon is not transcribed.
Tryptophan RNA-binding attenuator protein inhibitory protein
Tryptophan |
https://en.wikipedia.org/wiki/LZRW | Lempel–Ziv Ross Williams (LZRW) refers to variants of the LZ77 lossless data compression algorithms with an emphasis on improving compression speed through the use of hash tables and other techniques. This family was explored by Ross Williams, who published a series of algorithms beginning with LZRW1 in 1991.
The variants are:
LZRW1
LZRW1-A
LZRW2
LZRW3
LZRW3-A
LZRW4
LZRW5
The LZJB algorithm used in ZFS is derived from LZRW1.
Notes
Lossless compression algorithms
Free data compression software |
https://en.wikipedia.org/wiki/Maximization | Maximization or maximisation may refer to:
Maximization in the sense of exaggeration
Entropy maximization
Maximization (economics)
Profit maximization
Utility maximization problem
Budget-maximizing model
Shareholder value, maximization
Maximization (psychology)
Optimization (mathematics)
Expectation–maximization algorithm
See also
Minimization (disambiguation) |
https://en.wikipedia.org/wiki/Tetrode%20transistor | A tetrode transistor is any transistor having four active terminals.
Early tetrode transistors
There were two types of tetrode transistor developed in the early 1950s as an improvement over the point-contact transistor and the later grown-junction transistor and alloy-junction transistor. Both offered much higher speed than earlier transistors.
Point-contact transistor having two emitters. It became obsolete in the middle 1950s.
Modified grown-junction transistor or alloy-junction transistor having two connections at opposite ends of the base. It achieved its high speed by reducing the input to output capacitance. It became obsolete in the early 1960s with the development of the diffusion transistor.
Modern tetrode transistors
Dual emitter transistor, used in two-input transistor-transistor logic gates
Dual collector transistor, used in two-output integrated injection logic gates
Diffused planar silicon bipolar junction transistor, used in some integrated circuits. This transistor, apart from the three electrodes (emitter, base, and collector), has a fourth electrode or grid made of conducting material placed near the emitter-base junction from which it is insulated by a silica layer.
Field-effect tetrode
See also
Multigate transistor.
Pentode transistor
References
External links
Some application aspects of the tetrode transistors PDF (point contact)
The Tetrode Power Transistor PDF (alloy junction)
TRANSISTOR MUSEUM Historic Transistor Photo Gallery WESTERN ELECTRIC 3N |
https://en.wikipedia.org/wiki/Roger%20Squires | Roger Squires (22 February 1932 – 1 June 2023) was a British crossword compiler/setter, who lived in Ironbridge, Shropshire. He was best known for being the world's most prolific compiler. He compiled under the pseudonym Rufus in The Guardian, Dante in The Financial Times and was the Monday setter for the Daily Telegraph.
Early life
Squires was born in Tettenhall, Wolverhampton on 22 February 1932. educated at Wolverhampton Grammar School where he gained his School Certificate before joining the Royal Navy at age 15 as a Boy Seaman.
Squires served 15 years in the Fleet Air Arm, in which he trained as an observer and gained commission as its youngest ever officer and visited 44 countries, including being in the first aircraft to land in Port Said in the 1956 Suez Crisis. In March 1961 he survived an aircraft crash in the Indian Ocean off the coast of Ceylon, escaping from his Gannet AEW 60 feet below the sea surface and qualifying to become a member of the Goldfish Club (for survivors of aircraft ditchings).
Squires wrote, produced and appeared in a number of shows for the forces during his service. A keen sportsman, Squires represented the Royal Navy and Fleet Air Arm at football and cricket and became a qualified Football Association Coach and Referee.
His first published puzzle appeared in 1963, the year that he left the Navy and briefly worked as an entertainments manager for Butlin's, in the Wolverhampton Express & Star. The first national was the Radio Times, and in |
https://en.wikipedia.org/wiki/Low-energy%20electron%20microscopy | Low-energy electron microscopy, or LEEM, is an analytical surface science technique used to image atomically clean surfaces, atom-surface interactions, and thin (crystalline) films. In LEEM, high-energy electrons (15-20 keV) are emitted from an electron gun, focused using a set of condenser optics, and sent through a magnetic beam deflector (usually 60˚ or 90˚). The “fast” electrons travel through an objective lens and begin decelerating to low energies (1-100 eV) near the sample surface because the sample is held at a potential near that of the gun. The low-energy electrons are now termed “surface-sensitive” and the near-surface sampling depth can be varied by tuning the energy of the incident electrons (difference between the sample and gun potentials minus the work functions of the sample and system). The low-energy elastically backscattered electrons travel back through the objective lens, reaccelerate to the gun voltage (because the objective lens is grounded), and pass through the beam separator again. However, now the electrons travel away from the condenser optics and into the projector lenses. Imaging of the back focal plane of the objective lens into the object plane of the projector lens (using an intermediate lens) produces a diffraction pattern (low-energy electron diffraction, LEED) at the imaging plane and recorded in a number of different ways. The intensity distribution of the diffraction pattern will depend on the periodicity at the sample surface and is a d |
https://en.wikipedia.org/wiki/Statistical%20model%20specification | In statistics, model specification is part of the process of building a statistical model: specification consists of selecting an appropriate functional form for the model and choosing which variables to include. For example, given personal income together with years of schooling and on-the-job experience , we might specify a functional relationship as follows:
where is the unexplained error term that is supposed to comprise independent and identically distributed Gaussian variables.
The statistician Sir David Cox has said, "How [the] translation from subject-matter problem to statistical model is done is often the most critical part of an analysis".
Specification error and bias
Specification error occurs when the functional form or the choice of independent variables poorly represent relevant aspects of the true data-generating process. In particular, bias (the expected value of the difference of an estimated parameter and the true underlying value) occurs if an independent variable is correlated with the errors inherent in the underlying process. There are several different possible causes of specification error; some are listed below.
An inappropriate functional form could be employed.
A variable omitted from the model may have a relationship with both the dependent variable and one or more of the independent variables (causing omitted-variable bias).
An irrelevant variable may be included in the model (although this does not create bias, it involves overfitting |
https://en.wikipedia.org/wiki/FCCH | FCCH stands for Frequency Correction Channel. It is a downlink-only control channel in the GSM Um air interface.
The FCCH burst, defined in GSM 05.02 section 5.2.4, is an all-zero sequence that produces a fixed tone in the GMSK modulator output.
This tone enables the Mobile to lock its local oscillator to the BS clock as required in GSM specification 05.01 section 6.
The FCCH is transmitted in frames immediately before the SCH.
References
3GPP TS 05.01 Physical layer on the radio path; General description
3GPP TS 05.02 Multiplexing and Multiple Access on the Radio Path
http://www.3gpp.org/ftp/Specs/html-info/05-series.htm
GSM standard |
https://en.wikipedia.org/wiki/Spacistor | The spacistor was a type of transistor developed in the 1950s as an improvement over the point-contact transistor and the later alloy junction transistor. It offered much higher speed than earlier transistors. It became obsolete in the early 1960s with the development of the diffusion transistor.
It is composed of a P-N junction with a wide depletion region, inside which two additional contacts are made: the injector and the modulator. The P material was called the base and the N material was called the collector. The injector acted like a BJT (bipolar junction transistor) emitter, the modulator like a base, and the collector like its BJT namesake. It achieved high speed by reducing the charge carrier's transit time.
References
External links
The Spacistor, A New Class of High-Frequency Semiconductor Devices March 1957 - prone to oscillation
The Spacistor July 1961 - operate to 25 Mc (MHz)
Transistor types |
https://en.wikipedia.org/wiki/Sutherland%E2%80%93Hodgman%20algorithm | The Sutherland–Hodgman algorithm is an algorithm used for clipping polygons. It works by extending each line of the convex clip polygon in turn and selecting only vertices from the subject polygon that are on the visible side.
Description
The algorithm begins with an input list of all vertices in the subject polygon. Next, one side of the clip polygon is extended infinitely in both directions, and the path of the subject polygon is traversed. Vertices from the input list are inserted into an output list if they lie on the visible side of the extended clip polygon line, and new vertices are added to the output list where the subject polygon path crosses the extended clip polygon line.
This process is repeated iteratively for each clip polygon side, using the output list from one stage as the input list for the next. Once all sides of the clip polygon have been processed, the final generated list of vertices defines a new single polygon that is entirely visible. Note that if the subject polygon was concave at vertices outside the clipping polygon, the new polygon may have coincident (i.e., overlapping) edges – this is acceptable for rendering, but not for other applications such as computing shadows.
The Weiler–Atherton algorithm overcomes this by returning a set of divided polygons, but is more complex and computationally more expensive, so Sutherland–Hodgman is used for many rendering applications. Sutherland–Hodgman can also be extended into 3D space by clipping the polyg |
https://en.wikipedia.org/wiki/Synchronization%20%28alternating%20current%29 | In an alternating current (AC) electric power system, synchronization is the process of matching the frequency and phase and voltage of a generator or other source to an electrical grid in order to transfer power. If two unconnected segments of a grid are to be connected to each other, they cannot safely exchange AC power until they are synchronized.
A direct current (DC) generator can be connected to a power network simply by adjusting its open-circuit terminal voltage to match the network's voltage, by either adjusting its speed or its field excitation. The exact engine speed is not critical. However, an AC generator must additionally match its timing (frequency and phase) to the network voltage, which requires both speed and excitation to be systematically controlled for synchronization. This extra complexity was one of the arguments against AC operation during the war of currents in the 1880s. In modern grids, synchronization of generators is carried out by automatic systems.
Conditions
There are five conditions that must be met before the synchronization process takes place. The source (generator or sub-network) must have equal root-mean-square voltage, frequency, phase sequence, phase angle, and waveform to that of the system to which it is being synchronized.
Waveform and phase sequence are fixed by the construction of the generator and its connections to the system. During installation of a generator, careful checks are made to ensure the generator terminals and al |
https://en.wikipedia.org/wiki/Spin%20trapping | Spin trapping is an analytical technique employed in chemistry and biology for the detection and identification of short-lived free radicals through the use of electron paramagnetic resonance (EPR) spectroscopy. EPR spectroscopy detects paramagnetic species such as the unpaired electrons of free radicals. However, when the half-life of radicals is too short to detect with EPR, compounds known as spin traps are used to react covalently with the radical products and form more stable adduct that will also have paramagnetic resonance spectra detectable by EPR spectroscopy. The use of radical-addition reactions to detect short-lived radicals was developed by several independent groups by 1968.
Spin traps
The most commonly used spin traps are alpha-phenyl N-tertiary-butyl nitrone (PBN) and 5,5-dimethyl-pyrroline N-oxide (DMPO). More rarely, C-nitroso spin traps such as 3,5-dibromo-4-nitrosobenzenesulfonic acid (DBNBS) can be used: often additional hyperfine information is derived, but at a cost of specificity (due to facile non-radical addition of many compounds to C-nitroso species, and subsequent oxidation of the resulting hydroxylamine).
5-Diisopropoxyphosphoryl-5-methyl-1-pyrroline-N-oxide (DIPPMPO) spin trapping has been used in measuring superoxide production in mitochondria.
A comprehensive list of Spin Trapping molecules is maintained by the IUPAC.
Radical detection
A common method for spin-trapping involves the addition of radical to a nitrone spin trap resulting i |
https://en.wikipedia.org/wiki/Covariance%20and%20contravariance | Covariance and contravariance may refer to:
Covariance and contravariance of vectors, in mathematics and theoretical physics
Covariance and contravariance of functors, in category theory
Covariance and contravariance (computer science), whether a type system preserves the ordering ≤ of types
See also
Covariance, in probability theory and statistics, the measure of how much two random variables vary together
Covariance (disambiguation) |
https://en.wikipedia.org/wiki/Senile%20osteoporosis | Senile osteoporosis has been recently recognized as a geriatric syndrome with a particular pathophysiology. There are different classification of osteoporosis: primary, in which bone loss is a result of aging and secondary, in which bone loss occurs from various clinical and lifestyle factors. Primary, or involuntary osteoporosis, can further be classified into Type I or Type II. Type I refers to postmenopausal osteoporosis and is caused by the deficiency of estrogen. While senile osteoporosis is categorized as an involuntary, Type II, and primary osteoporosis, which affects both men and women over the age of 70 years. It is accompanied by vitamin D deficiency, body's failure to absorb calcium, and increased parathyroid hormone.
Research over the years has shown that senile osteoporosis is the product of a skeleton in an advanced stage of life and can be caused by a deficiency caused by calcium. However, physicians are also coming to the conclusion that multiple mechanisms in the development stages of the disease interact together resulting in an osteoporotic bone, regardless of age. Still, elderly people make up the fastest growing population in the world. As bone mass declines with age, the risk of fractures increases. Annual incidence of osteoporotic fractures is more than 1.5 million in the US and notably 20% of people die during the first year after a hip fracture.
It costs the US health system around $17 billion annually, with the cost projecting to $50 billion by 204 |
https://en.wikipedia.org/wiki/New%20York%20State%20Sportswriters%20Association | The New York State Sportswriters Association (NYSSWA), founded in 1967, is a source of reference information and statistics about scholastic athletics in the state. Begun by sportswriters Larry Serrell of the Schenectady Daily Gazette and Chuck Korbar of the Buffalo Evening News, NYSSWA membership grew from 12 in 1967 to 246 in 1971 and over 500 annual subscribers by 1995, according to the organization.
The active readership includes newspapers, radio and television stations in the state, as well as high school coaches and administrators, college sports coaches and the parents of athletes. The organization's biggest undertaking is the eight-page newsletter that is published 50 times a year. The NYSSWA publishes weekly team rankings in all major sports and also selects all-state teams in soccer, basketball, football, baseball, and softball. The NYSSWA newsletter has been edited and distributed for over 40 years by Neil Kerr of the Syracuse Post-Standard.
See also
National Sports Media Association
New Jersey Sports Writers Association
Philadelphia Sports Writers Association
External links
Official website
Sports in New York (state)
High school sports in New York (state)
College sports in New York (state)
American sports journalism organizations
Journalism-related professional associations
Non-profit organizations based in New York (state)
Sports organizations established in 1967
1967 establishments in New York (state) |
https://en.wikipedia.org/wiki/Qa-1b | Within molecular and cell biology, Qa-1b is a MHC class I molecule and is the functional homolog of HLA-E in humans. Qa-1b is characterised by its limited polymorphisms and small peptide repertoire. Qa-1b binds to peptides derived from signal peptides of MHC class Ia molecule and interact with the CD94/NKG2 receptors on natural killer cells. The Qa-1b-peptide complex signals natural killer cells not to engage in cell lysis. Despite its homology with HLA-E, it seems that Qa-1b evolved a similar function to HLA-E coincidentally.
References
Biomolecules |
https://en.wikipedia.org/wiki/Home%20runs%20per%20nine%20innings | In baseball statistics, home runs allowed per 9 innings pitched (HR/9IP or HR/9) or home runs allowed per nine innings (denoted by HR/9) is the average number of home runs given up by a pitcher per nine innings pitched. It is determined by multiplying the number of home runs allowed by nine and dividing by the number of innings pitched. Pitchers with high fly ball rates are more likely than pitchers with high ground ball rates to have high HR/9 rates.
Leaders
The career leaders in HR/9IP through 2018 were Jim Devlin (0.0448), Al Spalding (0.0468), and Reb Russell (0.0488).
There were 87 single-season leaders in HR/9IP through 2018 who had pitched a season without giving up a home run. All played prior to 1927.
The active leaders in HR/9IP through 2018 were Clayton Kershaw (0.6225), Adam Wainwright (0.6755), and Charlie Morton (0.7682).
References
Pitching statistics |
https://en.wikipedia.org/wiki/Lie%20algebra%20bundle | In mathematics, a weak Lie algebra bundle
is a vector bundle over a base space X together with a morphism
which induces a Lie algebra structure on each fibre .
A Lie algebra bundle is a vector bundle in which
each fibre is a Lie algebra and for every x in X, there is an open set containing x, a Lie algebra L and a homeomorphism
such that
is a Lie algebra isomorphism.
Any Lie algebra bundle is a weak Lie algebra bundle, but the converse need not be true in general.
As an example of a weak Lie algebra bundle that is not a strong Lie algebra bundle, consider the total space over the real line . Let [.,.] denote the Lie bracket of and deform it by the real parameter as:
for and .
Lie's third theorem states that every bundle of Lie algebras can locally be integrated to a bundle of Lie groups. In general globally the total space might fail to be Hausdorff. But if all fibres of a real Lie algebra bundle over a topological space are mutually isomorphic as Lie algebras, then it is a locally trivial Lie algebra bundle. This result was proved by proving that the real orbit of a real point under an algebraic group is open in the real part of its complex orbit. Suppose the base space is Hausdorff and fibers of total space are isomorphic as Lie algebras then there exists a Hausdorff Lie group bundle over the same base space whose Lie algebra bundle is isomorphic to the given Lie algebra bundle. Every semi simple Lie algebra bundle is locally trivial. Hence there exist a H |
https://en.wikipedia.org/wiki/Matrix%20determinant%20lemma | In mathematics, in particular linear algebra, the matrix determinant lemma computes the determinant of the sum of an invertible matrix A and the dyadic product, uvT, of a column vector u and a row vector vT.
Statement
Suppose A is an invertible square matrix and u, v are column vectors. Then the matrix determinant lemma states that
Here, uvT is the outer product of two vectors u and v.
The theorem can also be stated in terms of the adjugate matrix of A:
in which case it applies whether or not the square matrix A is invertible.
Proof
First the proof of the special case A = I follows from the equality:
The determinant of the left hand side is the product of the determinants of the three matrices. Since the first and third matrix are triangular matrices with unit diagonal, their determinants are just 1. The determinant of the middle matrix is our desired value. The determinant of the right hand side is simply (1 + vTu). So we have the result:
Then the general case can be found as:
Application
If the determinant and inverse of A are already known, the formula provides a numerically cheap way to compute the determinant of A corrected by the matrix uvT. The computation is relatively cheap because the determinant of A + uvT does not have to be computed from scratch (which in general is expensive). Using unit vectors for u and/or v, individual columns, rows or elements of A may be manipulated and a correspondingly updated determinant computed relatively cheaply in this |
https://en.wikipedia.org/wiki/Monte%20Alto%20photovoltaic%20power%20plant | The Monte Alto photovoltaic power plant in Spain has a generating capacity of 9.55 megawatts peak (MWp) and will generate 14 million kilowatt-hours of electricity per annum. It cost 65 million euros [US$87 million].
The installation covers an area of 51 hectares on agricultural land near the locality of Milagro (Navarre) and contains 889 solar structures, of which 864 are equipped with automated solar tracking. The rest are fixed structures adapted to the relief of the terrain.
In five years Acciona Energy has developed seven "solar gardens" in Navarre with a total capacity of 20 MWp, and another two are under construction in Castilla-La Mancha. Overall, the company's installed capacity is 23 megawatts (MW), through the approximately 3,000 automated solar monitoring structures, and represents a total investment of 177 million euros [US$236 million] shared among more than 2,000 owners. The yield from these investments is somewhere between 8 and 10% and the payback of the investment is estimated at around 10 years.
See also
Photovoltaics
Renewable energy in the European Union
Solar power in Spain
References
Photovoltaic power stations in Spain |
https://en.wikipedia.org/wiki/En-V | EN-V can refer to:
The LG enV (VX9900) cell phone
The General Motors EN-V autonomous electronic car prototype. |
https://en.wikipedia.org/wiki/PicoChip | Picochip was a venture-backed fabless semiconductor company based in Bath, England, founded in 2000. In January 2012 Picochip was acquired by Mindspeed Technologies, Inc and subsequently by Intel.
The company was active in two areas, with two distinct product families.
Picochip was one of the first companies to start developing solutions for small cell basestation (femtocells), for homes and offices. These help combat reception issues such as: dropped calls, poor sound quality, delays, and slow downloads. The idea is to increase the capacity of cellular networks and to address coverage holes.
Multi-core DSP
Picochip developed a multi-core digital signal processor, the picoArray. This integrates 250–300 individual DSP cores onto a single die (depending on the specific product) and as such it can be described as a Massively parallel processor array. Each of these cores is a 16-bit processor with Harvard architecture, local memory and 3-way VLIW. Although each device contained 250–300 processors, the architecture allowed devices to be connected to form far larger systems, in some cases with tens of thousands of cores.
The company had three multi-core DSP products (PC202 / 203 / 205) that delivered approximately 40 GMACS and 200 GIPS of performance. The earlier PC102 is obsolete.
The programming model allows each processor to be coded independently (in ANSI C or assembler) and then to communicate over an any:any interconnect mesh. The communication flows are fixed at comp |
https://en.wikipedia.org/wiki/CDR%20Canal%202 | CDR Canal 2 is a Costa Rican music television channel. The frequency belonged to Roxie Blen until 2011 when the station was sold to Central de Radios, a unit of Repretel. The channel broadcasts on digital channel 11.2 which is used for its sister channel Canal 11 due to the frequency being impossible to convert to digital until 2021. The channel was previously owned by Univision which was named as Univsion Canal 2 until 2000.
Television stations in Costa Rica
Spanish-language television stations
Television channels and stations established in 1970 |
https://en.wikipedia.org/wiki/Carbamoyl%20phosphate%20synthetase | Carbamoyl phosphate synthetase catalyzes the ATP-dependent synthesis
of carbamoyl phosphate from glutamine () or ammonia () and bicarbonate. This enzyme catalyzes the reaction of ATP and bicarbonate to produce carboxy phosphate and ADP. Carboxy phosphate reacts with ammonia to give carbamic acid. In turn, carbamic acid reacts with a second ATP to give carbamoyl phosphate plus ADP.
It represents the first committed step in pyrimidine and arginine biosynthesis in prokaryotes and eukaryotes, and in the urea cycle in most terrestrial vertebrates. Most prokaryotes carry one form of CPSase that participates in both arginine and pyrimidine biosynthesis, however certain bacteria can have separate forms.
There are three different forms that serve very different functions:
Carbamoyl phosphate synthetase I (mitochondria, urea cycle)
Carbamoyl phosphate synthetase II (cytosol, pyrimidine metabolism).
Carbamoyl phosphate synthetase III (found in fish).
Mechanism
Carbamoyl phosphate synthase has three main steps in its mechanism and is, in essence, irreversible.
Bicarbonate ion is phosphorylated with ATP to create .
The then reacts with ammonia to form carbamic acid, releasing inorganic phosphate.
A second molecule of ATP then phosphorylates carbamic acid, creating carbamoyl phosphate.
The activity of the enzyme is known to be inhibited by both Tris and HEPES buffers.
Structure
Carbamoyl phosphate synthase (CPSase) is a heterodimeric enzyme composed of a small and a large su |
https://en.wikipedia.org/wiki/Carbamoyl%20phosphate%20synthase%20II | Carbamoyl phosphate synthetase (glutamine-hydrolysing) () is an enzyme that catalyzes the reactions that produce carbamoyl phosphate in the cytosol (as opposed to type I, which functions in the mitochondria). Its systemic name is hydrogen-carbonate:L-glutamine amido-ligase (ADP-forming, carbamate-phosphorylating).
In pyrimidine biosynthesis, it serves as the rate-limiting enzyme and catalyzes the following reaction:
2 ATP + L-glutamine + HCO3− + H2O 2 ADP + phosphate + L-glutamate + carbamoyl phosphate (overall reaction)
(1a) L-glutamine + H2O L-glutamate + NH3
(1b) 2 ATP + HCO3− + NH3 2 ADP + phosphate + carbamoyl phosphate
It is activated by ATP and PRPP and it is inhibited by UTP (Uridine triphosphate)
Neither CPSI nor CPSII require biotin as a coenzyme, as seen with most carboxylation reactions.
It is one of the three enzyme functions coded by the CAD gene. It is classified under .
See also
Carbamoyl phosphate synthetase I
Carbamoyl phosphate synthetase III
References
External links
EC 6.3.5 |
https://en.wikipedia.org/wiki/Dihydroorotase | Dihydroorotase (, carbamoylaspartic dehydrase, dihydroorotate hydrolase) is an enzyme which converts carbamoyl aspartic acid into 4,5-dihydroorotic acid in the biosynthesis of pyrimidines. It forms a multifunctional enzyme with carbamoyl phosphate synthetase and aspartate transcarbamoylase. Dihydroorotase is a zinc metalloenzyme.
See also
Pyrimidine biosynthesis
References
External links
EC 3.5.2 |
https://en.wikipedia.org/wiki/Orotate%20phosphoribosyltransferase | Orotate phosphoribosyltransferase (OPRTase) or orotic acid phosphoribosyltransferase is an enzyme involved in pyrimidine biosynthesis. It catalyzes the formation of orotidine 5'-monophosphate (OMP) from orotate and phosphoribosyl pyrophosphate. In yeast and bacteria, orotate phosphoribosyltransferase is an independent enzyme with a unique gene coding for the protein, whereas in mammals and other multicellular organisms, the catalytic function is carried out by a domain of the bifunctional enzyme UMP synthase (UMPS).
Biological background
As OPRTase is part of a bifunctional complex UMP synthase in humans, the function and stability of this enzyme is not necessarily directly associated with disorders in the human body. It is however reasonable to believe that a dysfunction in one of the enzymes will cause a dysfunction of the whole enzyme. Defects in UMP synthase is associated with hypochromic anemia. In mammals, this bifunctional enzyme UMPS converts orotic acid into uridine monophosphate (UMP). Orotate phosphoribosyltransferase is located at the N-terminal domain of UMP synthase. This process happens in multiple steps with orotate phosphoribosyltransferase responsible for the first step of adding a ribose ring to orotate. In this step, orotic acid is converted into orotidylate using PRPP (phosphoribosyl pyrophosphate) as a cosubstrate. This reaction is driven by the hydrolysis of pyrophosphate. Orotidylate decarboxylase is located at the C-terminal domain of UMPS and c |
https://en.wikipedia.org/wiki/DBAG%20Class%20422 | The Class 422 is a series of four-car electric multiple units that are a derivative of the DBAG Class 423. The two inner cars in the set are designated as Class 432 vehicles.
History
The units were commissioned by Deutsche Bahn in 2005. 78 units worth €343 million were built by Bombardier Transportation and Alstom and delivered between March 2008 and October 2010. They are now used in such places as like on the Rhine-Ruhr S-Bahn which operate in cities like Köln and Düsseldorf as well as the Ruhr area.
Deutsche Bahn uses the units on the Rhine-Ruhr S-Bahn network, unlike most S-Bahn Networks which use similar DBAG Class 423 trains. The inner carriages are called Class 432. Following a timetable change in December of 2019 the units are currently used exclusively on the S1, S4, S5 and S6 lines of the network.
Electric multiple units of Germany
15 kV AC multiple units
Bombardier Transportation multiple units
Alstom multiple units
Train-related introductions in 2008 |
https://en.wikipedia.org/wiki/Harish-Chandra%27s%20regularity%20theorem | In mathematics, Harish-Chandra's regularity theorem, introduced by , states that every invariant eigendistribution on a semisimple Lie group, and in particular every character of an irreducible unitary representation on a Hilbert space, is given by a locally integrable function. proved a similar theorem for semisimple p-adic groups.
had previously shown that any invariant eigendistribution is analytic on the regular elements of the group, by showing that on these elements it is a solution of an elliptic differential equation. The problem is that it may have singularities on the singular elements of the group; the regularity theorem implies that these singularities are not too severe.
Statement
A distribution on a group G or its Lie algebra is called invariant if it is invariant under conjugation by G.
A distribution on a group G or its Lie algebra is called an eigendistribution if it is an eigenvector of the center of the universal enveloping algebra of G (identified with the left and right invariant differential operators of G).
Harish-Chandra's regularity theorem states that any invariant eigendistribution on a semisimple group or Lie algebra is a locally integrable function.
The condition that it is an eigendistribution can be relaxed slightly to the condition that its image under the center of the universal enveloping algebra is finite-dimensional. The regularity theorem also implies that on each Cartan subalgebra the distribution can be written as a finite sum of |
https://en.wikipedia.org/wiki/Fukushima%27s%20Theorem | In physics, Fukushima's Theorem holds that for all points beneath the ionosphere the magnetic fields from field-aligned currents and their corresponding Pedersen currents exactly cancel. By superposition the total magnetic field at the ground is then equal to the magnetic field from just the ionospheric Hall currents.
Fukushima's Theorem holds in any planar or spherical geometry, provided that the field-aligned currents are perpendicular to the ground, and that the ionospheric conductance is spatially constant. Neither of these conditions holds strongly in the auroral region of the Earth's ionosphere.
Journal articles
Naoshi Fukushima, "Generalized theorem for no ground magnetic effect of vertical currents connected with Pedersen currents in the uniform-conductivity ionosphere", Rep. Ionos.Space Res.Jap 30, 35-50 (1976).
Space science |
https://en.wikipedia.org/wiki/Orotic%20aciduria | Orotic aciduria (AKA hereditary orotic aciduria) is a disease caused by an enzyme deficiency, resulting in a decreased ability to synthesize pyrimidines. It was the first described enzyme deficiency of the de novo pyrimidine synthesis pathway.
Orotic aciduria is characterized by excessive excretion of orotic acid in urine because of the inability to convert orotic acid to UMP. It causes megaloblastic anemia and may be associated with mental and physical developmental delays.
Signs and symptoms
Patients typically present with excessive orotic acid in the urine, failure to thrive, developmental delay, and megaloblastic anemia which cannot be cured by administration of vitamin B12 or folic acid.
Cause and genetics
This autosomal recessive disorder is caused by a deficiency in the enzyme UMPS, a bifunctional protein that includes the enzyme activities of OPRT and ODC. In one study of three patients, UMPS activity ranged from 2-7% of normal levels.
Two types of orotic aciduria have been reported. Type I has a severe deficiency of both activities of UMP synthase. In Type II orotic aciduria, the ODC activity is deficient while OPRT activity is elevated. As of 1988, only one case of type II orotic aciduria had ever been reported.
Orotic aciduria is associated with megaloblastic anemia due to decreased pyrimidine synthesis, which leads to decreased nucleotide-lipid cofactors needed for erythrocyte membrane synthesis in the bone marrow.
Diagnosis
Elevated urinary orotic acid le |
https://en.wikipedia.org/wiki/Methylenedioxyallylamphetamine | Methylenedioxyallylamphetamine (MDAL or 3,4-methylenedioxy-N-allylamphetamine) is a lesser-known psychedelic drug. It is also the N-allyl derivative of 3,4-methylenedioxyamphetamine (MDA). MDAL was first synthesized by Alexander Shulgin. In his book PiHKAL, the minimum dosage is listed as 180 mg, and the duration unknown. MDAL produces few to no effects on its own, but may enhance the effects of LSD. Very little data exists about the pharmacological properties, metabolism, and toxicity of MDAL.
Legality
United Kingdom
This substance is a Class A drug in the Drugs controlled by the UK Misuse of Drugs Act.
See also
Phenethylamine
MDPR
References
Substituted amphetamines
Allyl compounds
Benzodioxoles |
https://en.wikipedia.org/wiki/Problem%20of%20points | The problem of points, also called the problem of division of the stakes, is a classical problem in probability theory. One of the famous problems that motivated the beginnings of modern probability theory in the 17th century, it led Blaise Pascal to the first explicit reasoning about what today is known as an expected value.
The problem concerns a game of chance with two players who have equal chances of winning each round. The players contribute equally to a prize pot, and agree in advance that the first player to have won a certain number of rounds will collect the entire prize. Now suppose that the game is interrupted by external circumstances before either player has achieved victory. How does one then divide the pot fairly? It is tacitly understood that the division should depend somehow on the number of rounds won by each player, such that a player who is close to winning will get a larger part of the pot. But the problem is not merely one of calculation; it also involves deciding what a "fair" division actually is.
Early solutions
Luca Pacioli considered such a problem in his 1494 textbook Summa de arithmetica, geometrica, proportioni et proportionalità. His method was to divide the stakes in proportion to the number of rounds won by each player, and the number of rounds needed to win did not enter his calculations at all.
In the mid-16th century Niccolò Tartaglia noticed that Pacioli's method leads to counterintuitive results if the game is interrupted when only |
https://en.wikipedia.org/wiki/Quartile%20coefficient%20of%20dispersion | In statistics, the quartile coefficient of dispersion is a descriptive statistic which measures dispersion and is used to make comparisons within and between data sets. Since it is based on quantile information, it is less sensitive to outliers than measures such as the coefficient of variation. As such, it is one of several robust measures of scale.
The statistic is easily computed using the first (Q1) and third (Q3) quartiles for each data set. The quartile coefficient of dispersion is:
Example
Consider the following two data sets:
A = {2, 4, 6, 8, 10, 12, 14}
n = 7, range = 12, mean = 8, median = 8, Q1 = 4, Q3 = 12, quartile coefficient of dispersion = 0.5
B = {1.8, 2, 2.1, 2.4, 2.6, 2.9, 3}
n = 7, range = 1.2, mean = 2.4, median = 2.4, Q1 = 2, Q3 = 2.9, quartile coefficient of dispersion = 0.18
The quartile coefficient of dispersion of data set A is 2.7 times as great (0.5 / 0.18) as that of data set B.
See also
Robust measures of scale
Coefficient of variation
Interquartile range
Median absolute deviation
References
Statistical deviation and dispersion
Statistical ratios |
https://en.wikipedia.org/wiki/Implicit%20curve | In mathematics, an implicit curve is a plane curve defined by an implicit equation relating two coordinate variables, commonly x and y. For example, the unit circle is defined by the implicit equation . In general, every implicit curve is defined by an equation of the form
for some function F of two variables. Hence an implicit curve can be considered as the set of zeros of a function of two variables. Implicit means that the equation is not expressed as a solution for either x in terms of y or vice versa.
If is a polynomial in two variables, the corresponding curve is called an algebraic curve, and specific methods are available for studying it.
Plane curves can be represented in Cartesian coordinates (x, y coordinates) by any of three methods, one of which is the implicit equation given above. The graph of a function is usually described by an equation in which the functional form is explicitly stated; this is called an explicit representation. The third essential description of a curve is the parametric one, where the x- and y-coordinates of curve points are represented by
two functions both of whose functional forms are explicitly stated, and which are dependent on a common parameter
Examples of implicit curves include:
a line:
a circle:
the semicubical parabola:
Cassini ovals (see diagram),
(see diagram).
The first four examples are algebraic curves, but the last one is not algebraic. The first three examples possess simple parametric representati |
https://en.wikipedia.org/wiki/Epimerase%20and%20racemase | Epimerases and racemases are isomerase enzymes that catalyze the inversion of stereochemistry in biological molecules.
Racemases catalyze the stereochemical inversion around the asymmetric carbon atom in a substrate having only one center of asymmetry. Epimerases catalyze the stereochemical inversion of the configuration about an asymmetric carbon atom in a substrate having more than one center of asymmetry, thus interconverting epimers.
Human epimerases include methylmalonyl-CoA epimerase, involved in the metabolic breakdown of the amino acids alanine, isoleucine, methionine and valine, and UDP-glucose 4-epimerase, which is used in the final step of galactose metabolism - catalyzing the reversible conversion of UDP-galactose to UDP-glucose.
See also
Galactose epimerase deficiency
References
External links
http://medical-dictionary.thefreedictionary.com/racemase
http://medical-dictionary.thefreedictionary.com/epimerase
Isomerases |
https://en.wikipedia.org/wiki/Sure | Sure may refer to:
Seemingly unrelated regressions
Series of Unsurprising Results in Economics (SURE), an economics academic journal
Sure, as probability, see certainty
Sure (brand), a brand of antiperspirant deodorant
Sure (company), a telecommunications company operating in British Crown Dependencies and Overseas Territories
Stein's unbiased risk estimate (SURE), in estimation theory
The river Sauer
In music
"Sure" (Every Little Thing song), from the album Eternity
"Sure" (Take That song), from the album Nobody Else
See also
Shure |
https://en.wikipedia.org/wiki/Purine%20metabolism | Purine metabolism refers to the metabolic pathways to synthesize and break down purines that are present in many organisms.
Biosynthesis
Purines are biologically synthesized as nucleotides and in particular as ribotides, i.e. bases attached to ribose 5-phosphate. Both adenine and guanine are derived from the nucleotide inosine monophosphate (IMP), which is the first compound in the pathway to have a completely formed purine ring system.
IMP
Inosine monophosphate is synthesized on a pre-existing ribose-phosphate through a complex pathway (as shown in the figure on the right). The source of the carbon and nitrogen atoms of the purine ring, 5 and 4 respectively, come from multiple sources. The amino acid glycine contributes all its carbon (2) and nitrogen (1) atoms, with additional nitrogen atoms from glutamine (2) and aspartic acid (1), and additional carbon atoms from formyl groups (2), which are transferred from the coenzyme tetrahydrofolate as 10-formyltetrahydrofolate, and a carbon atom from bicarbonate (1). Formyl groups build carbon-2 and carbon-8 in the purine ring system, which are the ones acting as bridges between two nitrogen atoms.
A key regulatory step is the production of 5-phospho-α-D-ribosyl 1-pyrophosphate (PRPP) by ribose phosphate pyrophosphokinase, which is activated by inorganic phosphate and inactivated by purine ribonucleotides. It is not the committed step to purine synthesis because PRPP is also used in pyrimidine synthesis and salvage pathways.
Th |
https://en.wikipedia.org/wiki/Xanthosine%20monophosphate | Xanthosine monophosphate also called Xanthylate is an intermediate in purine metabolism. It is a ribonucleoside monophosphate. It is formed from IMP via the action of IMP dehydrogenase, and it forms GMP via the action of GMP synthase. Also, XMP can be released from XTP by enzyme deoxyribonucleoside triphosphate pyrophosphohydrolase containing (d)XTPase activity.
It is abbreviated XMP.
See also
Xanthosine
References
Further reading
Nucleotides
Xanthines |
https://en.wikipedia.org/wiki/GMP%20synthase | Guanosine monophosphate synthetase, () also known as GMPS is an enzyme that converts xanthosine monophosphate to guanosine monophosphate.
In the de novo synthesis of purine nucleotides, IMP is the branch point metabolite at which point the pathway diverges to the synthesis of either guanine or adenine nucleotides. In the guanine nucleotide pathway, there are 2 enzymes involved in converting IMP to GMP, namely IMP dehydrogenase (IMPD1), which catalyzes the oxidation of IMP to XMP, and GMP synthetase, which catalyzes the amination of XMP to GMP.
Enzymology
In enzymology, a GMP synthetase (glutamine-hydrolysing) () is an enzyme that catalyzes the chemical reaction
ATP + xanthosine 5'-phosphate + L-glutamine + H2O AMP + diphosphate + GMP + L-glutamate
The 4 substrates of this enzyme are ATP, xanthosine 5'-phosphate, L-glutamine, and H2O, whereas its 4 products are AMP, diphosphate, GMP, and L-glutamate.
This enzyme belongs to the family of ligases, specifically those forming carbon-nitrogen bonds carbon-nitrogen ligases with glutamine as amido-N-donor. The systematic name of this enzyme class is xanthosine-5'-phosphate:L-glutamine amido-ligase (AMP-forming). This enzyme participates in purine metabolism and glutamate metabolism. At least one compound, Psicofuranin is known to inhibit this enzyme.
Structural studies
As of late 2007, 5 structures have been solved for this class of enzymes, with PDB accession codes , , , , and .
Role in metabolism
Purine metabolism
G |
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