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https://en.wikipedia.org/wiki/Bach%27s%20algorithm
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Bach's algorithm is a probabilistic polynomial time algorithm for generating random numbers along with their factorizations, named after its discoverer, Eric Bach. It is of interest because no algorithm is known that efficiently factors numbers, so the straightforward method, namely generating a random number and then factoring it, is impractical.
The algorithm performs, in expectation, O(log n) primality tests.
A simpler, but less efficient algorithm (performing, in expectation, primality tests), is due to Adam Kalai.
Bach's algorithm may theoretically be used within cryptographic algorithms.
Overview
Bach's algorithm produces a number uniformly at random in the range (for a given input ), along with its factorization. It does this by picking a prime number and an exponent such that , according to a certain distribution. The algorithm then recursively generates a number in the range , where , along with the factorization of . It then sets , and appends to the factorization of to produce the factorization of . This gives with logarithmic distribution over the desired range; rejection sampling is then used to get a uniform distribution.
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https://en.wikipedia.org/wiki/Synchronizer%20%28algorithm%29
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In computer science, a synchronizer is an algorithm that can be used to run a synchronous algorithm on top of an asynchronous processor network, so enabling the asynchronous system to run as a synchronous network.
The concept was originally proposed in (Awerbuch, 1985) along with three synchronizer algorithms named alpha, beta and gamma which provided different tradeoffs in terms of time and message complexity. Essentially, they are a solution to the problem of asynchronous algorithms (which operate in a network with no global clock) being harder to design and often less efficient than the equivalent synchronous algorithms. By using a synchronizer, algorithm designers can deal with the simplified "ideal network" and then later mechanically produce a version that operates in more realistic asynchronous cases.
Available synchronizer algorithms
The three algorithms that Awerbuch provided in his original paper are as follows:
Alpha synchronizer: This has low time complexity but high message complexity.
Beta synchronizer: This has high time complexity but low message complexity.
Gamma synchronizer: This provides a reasonable tradeoff between alpha and beta by providing fairly low time and message complexity.
Since the original paper, other synchronizer algorithms have been proposed in the literature.
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https://en.wikipedia.org/wiki/Johnson%20bound
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In applied mathematics, the Johnson bound (named after Selmer Martin Johnson) is a limit on the size of error-correcting codes, as used in coding theory for data transmission or communications.
Definition
Let be a q-ary code of length , i.e. a subset of . Let be the minimum distance of , i.e.
where is the Hamming distance between and .
Let be the set of all q-ary codes with length and minimum distance and let denote the set of codes in such that every element has exactly nonzero entries.
Denote by the number of elements in . Then, we define to be the largest size of a code with length and minimum distance :
Similarly, we define to be the largest size of a code in :
Theorem 1 (Johnson bound for ):
If ,
If ,
Theorem 2 (Johnson bound for ):
(i) If
(ii) If , then define the variable as follows. If is even, then define through the relation ; if is odd, define through the relation . Let . Then,
where is the floor function.
Remark: Plugging the bound of Theorem 2 into the bound of Theorem 1 produces a numerical upper bound on .
See also
Singleton bound
Hamming bound
Plotkin bound
Elias Bassalygo bound
Gilbert–Varshamov bound
Griesmer bound
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https://en.wikipedia.org/wiki/National%20symbols%20of%20Iran
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Official symbols
Flag
Emblem
Derafsh Kaviani
Lion and Sun
Faravahar
Emblem of Iran
Anthem
Salām-e Shāh
Imperial Anthem of Iran
Ey Iran
Payandeh Bada Iran
Unofficial symbols
Cultural heritage
Musical instruments
SanturSetar
Tar
Kamancheh
Ney-anban
Chang
Daf
Holidays
Nowruz
13 Be-Dar
Tirgan
Mehregan
Yalda
Sadeh
Chaharshanbe Suri
LiteratureAvestaShahnamehMasnaviDivan of HafezGulistanBustan''
Mythology
Keyumars
Mashya and Mashyana
Jamshid
Arash
Rostam
Zahhak
Fereydun
Homa (griffin)
Shahbaz
Simorgh
Chamrosh
Games
Chess (Shatranj)
Backgammon (Nard)
Hokm
Shelem
Sports
Wrestling
Pahlevani and zoorkhaneh rituals
Polo
Arts
Persian calligraphy
Persian carpet
Persian literature
Persian miniature
Colors
Persian green
Persian blue
Persian red
Cuisine
Chelo kabab
Ghorme sabzi
Fesenjan
Abgoosht/Dizi stoneware
Salad Shirazi
Caviar/Beluga Sturgeon
Animals
Persian/Asiatic lion
Asiatic cheetah
Persian leopard
Persian cat
Persian fallow deer
Caspian horse
Nightingale
Falcon
Plants
Lotus
Rose
Saffron
Hyacinth
Lily
Pomegranate
Pistachio
Cypress
Tulip
Natural Monuments, Places, Architecture
Royal stars: Aldeberan, Regulus, Fomalhaut, Antares
Alborz
Mount Damavand
Persian Gulf
Persepolis
Azadi Tower/Azadi Square
Milad Tower
Pasargadae
Naqsh-e Jahan Square
Rostam's Mural
Rudkhan Castle
Persian gardens
Windcatcher
Qanat
People
Cyrus the Great
Avicenna
Ferdowsi
Hafez
Rumi
Omar Khayyam
Saadi
Attar of Nishapur
Nizami
Naser Khosrow
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https://en.wikipedia.org/wiki/List%20of%20neuroscientists
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Many famous neuroscientists are from the 20th and 21st century, as neuroscience is a fairly new science. However many anatomists, physiologists, biologists, neurologists, psychiatrists and other physicians and psychologists are considered to be neuroscientists as well. This list compiles the names of all neuroscientists with a corresponding Wikipedia biographical article, and is not necessarily a reflection of their relative importance in the field.
See also
History of neuroscience
List of cognitive neuroscientists
List of neurologists and neurosurgeons
List of women neuroscientists
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https://en.wikipedia.org/wiki/Influenza%20Genome%20Sequencing%20Project
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The Influenza Genome Sequencing Project (IGSP), initiated in early 2004, seeks to investigate influenza evolution by providing a public data set of complete influenza genome sequences from collections of isolates representing diverse species distributions.
The project is funded by the National Institute of Allergy and Infectious Diseases (NIAID), a division of the National Institutes of Health (NIH), and has been operating out of the NIAID Microbial Sequencing Center at The Institute for Genomic Research (TIGR, which in 2006 became The Venter Institute).
Sequence information generated by the project has been continually placed into the public domain through GenBank.
Origins
In late 2003, David Lipman, Lone Simonsen, Steven Salzberg, and a consortium of other scientists wrote a proposal to begin sequencing large numbers of influenza viruses at The Institute for Genomic Research (TIGR). Prior to this project, only a handful of flu genomes were publicly available. Their proposal was approved by the National Institutes of Health (NIH), and would later become the IGSP. New technology development led by Elodie Ghedin began at TIGR later that year, and the first publication describing > 100 influenza genomes appeared in 2005 in the journal Nature
Research goals
The project makes all sequence data publicly available through GenBank, an international, NIH-funded, searchable online database.
This research helps to provide international researchers with the information needed to develop new vaccines, therapies and diagnostics, as well as improve understanding of the overall molecular evolution of Influenza and other genetic factors that determine their virulence. Such knowledge could not only help mitigate the impact of annual influenza epidemics, but could also improve scientific knowledge of the emergence of pandemic influenza viruses.
Results
The project completed its first genomes in March 2005 and has rapidly accelerated since. By mid-2008, over 3000 isolates had bee
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https://en.wikipedia.org/wiki/Introduction%20to%20Automata%20Theory%2C%20Languages%2C%20and%20Computation
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Introduction to Automata Theory, Languages, and Computation is an influential computer science textbook by John Hopcroft and Jeffrey Ullman on formal languages and the theory of computation. Rajeev Motwani contributed to later editions beginning in 2000.
Nickname
The Jargon File records the book's nickname, Cinderella Book, thusly: "So called because the cover depicts a girl (putatively Cinderella) sitting in front of a Rube Goldberg device and holding a rope coming out of it. On the back cover, the device is in shambles after she has (inevitably) pulled on the rope."
Edition history and reception
The forerunner of this book appeared under the title Formal Languages and Their Relation to Automata in 1968. Forming a basis both for the creation of courses on the topic, as well as for further research, that book shaped the field of automata theory for over a decade, cf. (Hopcroft 1989).
The first edition of Introduction to Automata Theory, Languages, and Computation was published in 1979, the second edition in November 2000, and the third edition appeared in February 2006. Since the second edition, Rajeev Motwani has joined Hopcroft and Ullman as the third author. Starting with the second edition, the book features extended coverage of examples where automata theory is applied, whereas large parts of more advanced theory were taken out. While this makes the second and third editions more accessible to beginners, it makes it less suited for more advanced courses. The new bias away from theory is not seen positively by all: As Shallit quotes one professor, "they have removed all good parts." (Shallit 2008).
The first edition in turn constituted a major revision of a previous textbook also written by Hopcroft and Ullman, entitled Formal Languages and Their Relation to Automata. It was published in 1968 and is referred to in the introduction of the 1979 edition.
In a personal historical note regarding the 1968 book, Hopcroft states: "Perhaps the success of the boo
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https://en.wikipedia.org/wiki/Rustproofing
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Rustproofing is the prevention or delay of rusting of iron and steel objects, or the permanent protection against corrosion. Typically, the protection is achieved by a process of surface finishing or treatment. Depending on mechanical wear or environmental conditions, the degradation may not be stopped completely, unless the process is periodically repeated. The term is particularly used in the automobile industry.
Vehicle rustproofing
Factory
In the factory, car bodies are protected with special chemical formulations.
Typically, phosphate conversion coatings were used. Some firms galvanized part or all of their car bodies before the primer coat of paint was applied. If a car is body-on-frame, then the frame (chassis) must also be rustproofed. In traditional automotive manufacturing of the early- and mid-20th century, paint was the final part of the rustproofing barrier between the body shell and the atmosphere, except on the underside. On the underside, an underseal rubberized or PVC-based coating was often sprayed on. These products will be breached eventually and can lead to unseen corrosion that spreads underneath the underseal. Old 1960s and 1970s rubberized underseal can become brittle on older cars and is particularly liable to this.
The first electrodeposition primer was developed in the 1950s, but were found to be impractical for widespread use. Revised cathodic automotive electrocoat primer systems were introduced in the 1970s that markedly reduced the problem of corrosion that had been experienced by a vast number of automobiles in the first seven decades of automobile manufacturing. Termed e-coat, "electrocoat automotive primers are applied by totally submerging the assembled car body in a large tank that contains the waterborne e-coat, and the coating is applied through cathodic electrodeposition. This assures nearly 100% coverage of all metal surfaces by the primer. The coating chemistry is waterborne enamel based on epoxy, an aminoalcohol adduct,
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https://en.wikipedia.org/wiki/Phlegmon
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A phlegmon is a localized area of acute inflammation of the soft tissues. It is a descriptive term which may be used for inflammation related to a bacterial infection or non-infectious causes (e.g. pancreatitis). Most commonly, it is used in contradistinction to a "walled-off" pus-filled collection (abscess), although a phlegmon may progress to an abscess if untreated. A phlegmon can localize anywhere in the body. The Latin term phlegmōn is from Ancient Greek φλέγω (phlégō) 'burn'.
Signs and symptoms
As with any form of inflammation, phlegmon presents with inflammatory signs dolor (localized pain), calor (increase local tissue temperature), rubor (skin redness/hyperemia), tumor (either clear or non-clear bordered tissue swelling), functio laesa (diminish affected function). There may be systemic signs of infection, such as fever, general fatigue, chills, sweating, headache, loss of appetite.
Cause
Commonly caused by bacterial infection, as in the case of cellulitis or diverticulitis. Non-infectious causes of phlegmon include acute pancreatitis, where inflammation is caused by leaking of pancreatic digestive enzymes into the surrounding tissues.
Factors affecting the development of phlegmon are virulence of bacteria and immunity strength.
Diagnosis
In modern medicine, phlegmon is mostly used descriptively in the fields of surgery/surgical pathology and medical imaging. The ultrasound and CT imaging findings of phlegmon are those of focal tissue edema, with no loculated fluid collection to suggest the formation of an abscess.
Treatment
Since phlegmon describes an area of inflammation, and not a specific disease process, the treatment depends on the cause and severity of the inflammation. Bacterial infections such as cellulitis may be treated by antibiotic therapy, depending on the severity.
See also
Cellulitis
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https://en.wikipedia.org/wiki/SpareMiNT
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SpareMiNT is a software distribution based on FreeMiNT, which consists of a MiNT-like operating system (OS) and kernel plus GEM compatible AES (Application Environment Services).
Features and compatibility
The English language distribution is intended for the Atari ST and derivative m68k computers, clones and emulators, such as the FireBee project or Hatari and ARAnyM. The MiNT itself, also once called MultiTOS, provided an Atari TOS compatible OS replacement with multitasking and multi-user switching capabilities and Unix-like operation, all of which the original TOS lacked.
The distribution comes with Red Hat's rpm utility for managing the source- and binary packages. Unix/Linux-style software can be used, if ported, GEM-programs for TOS can run concurrently. The TOS clone EmuTOS, instead of Atari's original, can be used as a base to boot a MiNT, and e.g. XaAES, a modern AES derivate, as essential part of the GEM-GUI (Graphical user interface).
FreeMiNT, and therefore SpareMiNT, is basically the enhanced and greatly improved derivate, and can be used on today's computers, even on different hardware platforms via emulation or Virtual Machines, thanks to the flexibility of the original MiNT and its components that made further development possible.
Comparable Distributions
EasyMiNT
Derived from SpareMiNT is EasyMiNT, using its software repository and a GEM based installer, providing a folder system similar to the UNIX Filesystem Hierarchy Standard and German language translations to programs.
AFROS
AFROS (Atari FRee Operating System) comes as a set of files, creating a TOS compatible operating system; there exists a Live-CD to test. Its key components all consist of Free Software:
EmuTOS and FreeMiNT; fVDI (free Virtual Device Interface), clone of GEM's VDI; XaAES; TeraDesk (Tera Desktop), clone of the original Desktop Filemanager and "shell"
AFROS software is available to all Atari and/or TOS compatible platforms, but is optimized to be used with the ARA
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https://en.wikipedia.org/wiki/Mensurstrich
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(plural ) is a German term used in musical notation to denote a barline that is drawn between staves, but not across them. It is typically seen in modern editions of Medieval and Renaissance vocal polyphony, where it is intended to allow modern performers the convenience of barlines without having them interfere with the music, which was originally written without barlines. In most cases note values are allowed to cross over a without requiring a tie.
The convention of the was introduced by German musicologists such as Heinrich Besseler in the 1920s and became common in editorial practice by the mid-20th century. It is frequently applied in academic editions of 15th and 16th century music such as those in the multi-volume Corpus mensurabilis musicae published by the American Institute of Musicology.
A few modern composers (such as Hugo Distler, whose vocal music is reminiscent of Renaissance vocal polyphony) have made a practice of using it in their music in order to minimize the regularity of meter.
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https://en.wikipedia.org/wiki/Lattice%20model
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Lattice model may refer to:
Lattice model (physics), a physical model that is defined on a periodic structure with a repeating elemental unit pattern, as opposed to the continuum of space or spacetime
Lattice model (finance), a "discrete-time" model of the varying price over time of the underlying financial instrument, during the life of the instrument
Lattice model (mathematics), a regular tiling of a space by a primitive cell
Lattice model (biophysics), a class of Ising-type models for the description of biomacromolecules, their transformations and binding in gene regulation and signal transduction
Lattice-based access control, a complex access control model based on the interaction between any combination of objects and subjects
Lattice models
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https://en.wikipedia.org/wiki/Lattice%20model%20%28finance%29
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In finance, a lattice model is a technique applied to the valuation of derivatives, where a discrete time model is required. For equity options, a typical example would be pricing an American option, where a decision as to option exercise is required at "all" times (any time) before and including maturity. A continuous model, on the other hand, such as Black–Scholes, would only allow for the valuation of European options, where exercise is on the option's maturity date. For interest rate derivatives lattices are additionally useful in that they address many of the issues encountered with continuous models, such as pull to par. The method is also used for valuing certain exotic options, where because of path dependence in the payoff, Monte Carlo methods for option pricing fail to account for optimal decisions to terminate the derivative by early exercise, though methods now exist for solving this problem.
Equity and commodity derivatives
In general the approach is to divide time between now and the option's expiration into N discrete periods. At the specific time n, the model has a finite number of outcomes at time n + 1 such that every possible change in the state of the world between n and n + 1 is captured in a branch. This process is iterated until every possible path between n = 0 and n = N is mapped. Probabilities are then estimated for every n to n + 1 path. The outcomes and probabilities flow backwards through the tree until a fair value of the option today is calculated.
For equity and commodities the application is as follows. The first step is to trace the evolution of the option's key underlying variable(s), starting with today's spot price, such that this process is consistent with its volatility; log-normal Brownian motion with constant volatility is usually assumed. The next step is to value the option recursively: stepping backwards from the final time-step, where we have exercise value at each node; and applying risk neutral valuation at each ear
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https://en.wikipedia.org/wiki/Putty%20knife
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A putty knife is a specialized tool used when glazing single glazed windows, to work putty around the edges of each pane of glass. An experienced glazer will apply the putty by hand, and then smooth it with the knife. Modern insulated glazing may use other ways of securing the glass to the window frame.
A spackle knife (called a scraper in British English, also known as a spatula in American English) is also commonly called a "putty knife", and is used for scraping surfaces or spreading material such as plaster in various construction trades. Widths from 1" to 5" or 6" are commonly available. Wider-bladed knives up to about 12" are used for sheet rocking. Larger blades are made, but generally lack the stability of the smaller blades and do not make a perfectly flat surface.
Stiff-blade knives, typically 1 mm or .040" thick, are suitable for scraping. Flexible-blade knives, typically 0.5 mm or .020" thick, are suitable for spreading. Due to the conductive nature of metallic blades, they should be kept at a safe distance from electrical components.
Disposable knives, with handle and blade molded as a single piece of plastic, are suitable for occasional jobs such as spreading roof patching tar or mixing two-part adhesives, avoiding laborious cleanup which may involve hazardous solvents.
See also
Taping knife
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https://en.wikipedia.org/wiki/Carbogen
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Carbogen, also called Meduna's Mixture after its inventor Ladislas Meduna, is a mixture of carbon dioxide and oxygen gas. Meduna's original formula was 30% CO2 and 70% oxygen, but the term carbogen can refer to any mixture of these two gases, from 1.5% to 50% CO2.
Mechanism
When carbogen is inhaled, the increased level of carbon dioxide causes a perception, both psychological and physiological, of suffocation because the brain interprets an increase in blood carbon dioxide as a decrease in oxygen level, which would generally be the case under natural circumstances. Inhalation of carbogen causes the body to react as if it were not receiving sufficient oxygen: breathing quickens and deepens, heart rate increases, and cells release alkaline buffering agents to remove carbonic acid from the bloodstream.
Psychotherapy
Carbogen was once used in psychology and psychedelic psychotherapy to determine whether a patient would react to an altered state of consciousness or to a sensation of loss of control. Individuals who reacted especially negatively to carbogen were generally not administered other psychotherapeutic drugs for fear of similar reactions. Meduna administered carbogen to his patients to induce abreaction, which, with proper preparation and administration, he found could help clients become free of their neuroses. Carbogen users are said to have discovered unconscious contents of their minds, with the experience clearing away repressed material and freeing the subject for a smoother, more profound psychedelic experience.
One subject reported:
"After the second breath came an onrush of color, first a predominant sheet of beautiful rosy-red, following which came successive sheets of brilliant color and design, some geometric, some fanciful and graceful …. Then the colors separated; my soul drawing apart from the physical being, was drawn upward seemingly to leave the earth and to go upward where it reached a greater Spirit with Whom there was a communion, pro
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https://en.wikipedia.org/wiki/Commercial%20use%20of%20space
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Commercial use of space is the provision of goods or services of commercial value by using equipment sent into Earth orbit or outer space. This phenomenon – aka Space Economy (or New Space Economy) – is accelerating cross-sector innovation processes combining the most advanced space and digital technologies to develop a broad portfolio of space-based services. The use of space technologies and of the data they collect, combined with the most advanced enabling digital technologies is generating a multitude of business opportunities that include the development of new products and services all the way to the creation of new business models, and the reconfiguration of value networks and relationships between companies. If well leveraged such technology and business opportunities can contribute to the creation of tangible and intangible value, through new forms and sources of revenue, operating efficiency and the start of new projects leading to multidimensional (e.g. society, environment) positive impact. Examples of the commercial use of space include satellite navigation, satellite television and commercial satellite imagery. Operators of such services typically contract the manufacturing of satellites and their launch to private or public companies, which form an integral part of the space economy. Some commercial ventures have long-term plans to exploit natural resources originating outside Earth, for example asteroid mining. Space tourism, currently an exceptional activity, could also be an area of future growth, as new businesses strive to reduce the costs and risks of human spaceflight.
The first commercial use of outer space occurred in 1962, when the Telstar 1 satellite was launched to transmit television signals over the Atlantic Ocean. By 2004, global investment in all space sectors was estimated to be US$50.8 billion.
As of 2010, 31% of all space launches were commercial.
History
The first commercial use of satellites may have been the Telstar 1 satelli
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https://en.wikipedia.org/wiki/Square-free%20polynomial
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In mathematics, a square-free polynomial is a polynomial defined over a field (or more generally, an integral domain) that does not have as a divisor any square of a non-constant polynomial. A univariate polynomial is square free if and only if it has no multiple root in an algebraically closed field containing its coefficients. This motivates that, in applications in physics and engineering, a square-free polynomial is commonly called a polynomial with no repeated roots.
In the case of univariate polynomials, the product rule implies that, if divides , then divides the formal derivative of . The converse is also true and hence, is square-free if and only if is a greatest common divisor of the polynomial and its derivative.
A square-free decomposition or square-free factorization of a polynomial is a factorization into powers of square-free polynomials
where those of the that are non-constant are pairwise coprime square-free polynomials (here, two polynomials are said coprime is their greatest common divisor is a constant; in other words that is the coprimality over the field of fractions of the coefficients that is considered). Every non-zero polynomial admits a square-free factorization, which is unique up to the multiplication and division of the factors by non-zero constants. The square-free factorization is much easier to compute than the complete factorization into irreducible factors, and is thus often preferred when the complete factorization is not really needed, as for the partial fraction decomposition and the symbolic integration of rational fractions. Square-free factorization is the first step of the polynomial factorization algorithms that are implemented in computer algebra systems. Therefore, the algorithm of square-free factorization is basic in computer algebra.
Over a field of characteristic 0, the quotient of by its GCD with its derivative is the product of the in the above square-free decomposition. Over a perfect field of non-zero
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https://en.wikipedia.org/wiki/Ervand%20Kogbetliantz
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Ervand George Kogbetliantz (; February 22, 1888 in Rostov-on-the-Don – 1974 in Paris, France) was an Armenian-American mathematician and the first president of the Yerevan State University. He left Russia in 1918. He received a Doctorate in mathematics from the University of Paris in 1923. His mathematical work was mainly on infinite series, on the theory of orthogonal polynomials, on an algorithm for singular value decomposition which bears his name, on algorithms for the evaluation of elementary functions in computers, and the enumeration of prime elements of the Gaussian integers. He also invented a three-dimensional version of chess. He was working at his death with Bobby Fischer on a game of chess for three people. When he first went to America (1941), he taught Mathematics at Lehigh University. In the early 1950s, he was a consultant for IBM in New York City and taught at Columbia University. Prior to moving back to Paris and retiring, he was a professor at Rockefeller University.
Articles and books
Recherches sur la summabilité des séries ultrasphériques par la méthode des moyennes arithmétiques, J. Math. Pures Appl. 9, 107–187, 1924.
Fundamentals of mathematics from an advanced viewpoint, 4 volumes, Gordon and Breach Science Publishers, 1968.
(with Alice Krikorian) Handbook of first complex prime numbers, Gordon and Breach Science Publishers, 1971.
External links
Life magazine, 9 June 1952, on his three-dimensional chess board
Two photos of Kogbetliantz from the Pontigny Conference at Mount Holyoke College in 1944
1888 births
1974 deaths
Deaths from cancer in France
20th-century Armenian mathematicians
Numerical analysts
Singular value decomposition
Academic staff of Yerevan State University
University of Paris alumni
Soviet emigrants to the United States
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https://en.wikipedia.org/wiki/Tree%20spanner
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A tree k-spanner (or simply k-spanner) of a graph is a spanning subtree of in which the distance between every pair of vertices is at most times their distance in .
Known Results
There are several papers written on the subject of tree spanners. One of these was entitled Tree Spanners written by mathematicians Leizhen Cai and Derek Corneil, which explored theoretical and algorithmic problems associated with tree spanners. Some of the conclusions from that paper are listed below. is always the number of vertices of the graph, and is its number of edges.
A tree 1-spanner, if it exists, is a minimum spanning tree and can be found in time (in terms of complexity) for a weighted graph, where . Furthermore, every tree 1-spanner admissible weighted graph contains a unique minimum spanning tree.
A tree 2-spanner can be constructed in time, and the tree -spanner problem is NP-complete for any fixed integer .
The complexity for finding a minimum tree spanner in a digraph is , where is a functional inverse of the Ackermann function
The minimum 1-spanner of a weighted graph can be found in time.
For any fixed rational number , it is NP-complete to determine whether a weighted graph contains a tree t-spanner, even if all edge weights are positive integers.
A tree spanner (or a minimum tree spanner) of a digraph can be found in linear time.
A digraph contains at most one tree spanner.
The quasi-tree spanner of a weighted digraph can be found in time.
See also
Graph spanner
Geometric spanner
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https://en.wikipedia.org/wiki/Lists%20of%20animals
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Animals are multicellular eukaryotic organisms in the biological kingdom Animalia. With few exceptions, animals consume organic material, breathe oxygen, are able to move, reproduce sexually, and grow from a hollow sphere of cells, the blastula, during embryonic development. Over 1.5 million living animal species have been described—of which around 1 million are insects—but it has been estimated there are over 7 million in total. Animals range in size from 8.5 millionths of a metre to long and have complex interactions with each other and their environments, forming intricate food webs. The study of animals is called zoology.
Animals may be listed or indexed by many criteria, including taxonomy, status as endangered species, their geographical location, and their portrayal and/or naming in human culture.
By common name
List of animal names (male, female, young, and group)
By aspect
List of common household pests
List of animal sounds
List of animals by number of neurons
By domestication
List of domesticated animals
By eating behaviour
List of herbivorous animals
List of omnivores
List of carnivores
By endangered status
IUCN Red List endangered species (Animalia)
United States Fish and Wildlife Service list of endangered species
By extinction
List of extinct animals
List of extinct birds
List of extinct mammals
List of extinct cetaceans
List of extinct butterflies
By region
Lists of amphibians by region
Lists of birds by region
Lists of mammals by region
Lists of reptiles by region
By individual (real or fictional)
Real
Lists of snakes
List of individual cats
List of oldest cats
List of giant squids
List of individual elephants
List of historical horses
List of leading Thoroughbred racehorses
List of individual apes
List of individual bears
List of giant pandas
List of individual birds
List of individual bovines
List of individual cetaceans
List of individual dogs
List of oldest dogs
List of individual monkeys
List of individual pigs
List of w
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https://en.wikipedia.org/wiki/Brightest%20cluster%20galaxy
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A brightest cluster galaxy (BCG) is defined as the brightest galaxy in a cluster of galaxies. BCGs include the most massive galaxies in the universe. They are generally elliptical galaxies which lie close to the geometric and kinematical center of their host galaxy cluster, hence at the bottom of the cluster potential well. They are also generally coincident with the peak of the cluster X-ray emission.
Formation scenarios for BCGs include:
Cooling flow—Star formation from the central cooling flow in high density cooling centers of X-ray cluster halos.
The study of accretion populations in BCGs has cast doubt over this theory and astronomers have seen no evidence of cooling flows in radiative cooling clusters. The two remaining theories exhibit healthier prospects.
Galactic cannibalism—Galaxies sink to the center of the cluster due to dynamical friction and tidal stripping.
Galactic merger—Rapid galactic mergers between several galaxies take place during cluster collapse.
It is possible to differentiate the cannibalism model from the merging model by considering the formation period of the BCGs. In the cannibalism model, there are numerous small galaxies present in the evolved cluster, whereas in the merging model, a hierarchical cosmological model is expected due to the collapse of clusters. It has been shown that the orbit decay of cluster galaxies is not effective enough to account for the growth of BCGs.
The merging model is now generally accepted as the most likely one, but recent observations are at odds with some of its predictions. For example, it has been found that the stellar mass of BCGs was assembled much earlier than the merging model predicts.
BCGs are divided into various classes of galaxies: giant ellipticals (gE), D galaxies and cD galaxies. cD and D galaxies both exhibit an extended diffuse envelope surrounding an elliptical-like nucleus akin to regular elliptical galaxies. The light profiles of BCGs are often described by a Sersic surface
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https://en.wikipedia.org/wiki/Propyl%20gallate
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Propyl gallate, or propyl 3,4,5-trihydroxybenzoate is an ester formed by the condensation of gallic acid and propanol. Since 1948, this antioxidant has been added to foods containing oils and fats to prevent oxidation. As a food additive, it is used under the E number E310.
Description
Propyl gallate is an antioxidant. It protects against oxidation by hydrogen peroxide and oxygen free radicals.
Uses
Propyl gallate is used to protect oils and fats in products from oxidation; it is used in foods, cosmetics, hair products, adhesives, and lubricants.
It is used as a triplet state quencher and an antioxidant in fluorescence microscopy.
Biological effects
A 1993 study in fat rodents found little or no effect on carcinogenesis by propyl gallate.
A 2009 study found that propyl gallate acts as an estrogen antagonist.
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https://en.wikipedia.org/wiki/Matthew%20Hennessy
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Matthew Hennessy is an Irish computer scientist who has contributed especially to concurrency, process calculi and programming language semantics.
Career
During 1976–77, Matthew Hennessy was an assistant professor at the University of Waterloo in Canada. Then during 1977–78, he was a visiting professor at the Universidade Federal de Pernambuco in Brazil. Subsequently, he was a research associate (1979–81) and then lecturer (1981–85) at the University of Edinburgh in Scotland. During 1985, he was a guest lecturer/researcher at the University of Aarhus in Denmark.
Hennessy was Professor of Computer Science at the Department of Informatics, University of Sussex, England, from 1985 until 2008. Since then, Hennessy has held a research professorship at the Department of Computer Science, Trinity College, Dublin.
Hennessy's research interests are in the area of the semantic foundations of programming and specification languages, particularly involving distributed computing, including mobile computing. He also has an interest in verification tools. His co-authors include Robin Milner and Gordon Plotkin.
Hennessy is a member of the Academy of Europe. He held a Royal Society/Leverhulme Trust Senior Research Fellowship during 2005–06 and has a
Science Foundation Ireland Research Professorship at Trinity College Dublin.
Books
Matthew Hennessy has written a number of books:
Hennessy, Matthew. A Distributed Pi-Calculus. Cambridge University Press, Cambridge, UK, 2007. .
Hennessy, Matthew. Algebraic Theory of Processes. The MIT Press, Cambridge, Massachusetts, 1988. .
Hennessy, Matthew. The Semantics of Programming Languages: An Elementary Introduction using Structural Operational Semantics. John Wiley and Sons, New York, 1990. .
See also
Hennessy–Milner logic
Ó hAonghusa
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https://en.wikipedia.org/wiki/Nintendo%20Wi-Fi%20USB%20Connector
|
The Nintendo Wi-Fi USB Connector is a wireless game adapter, developed by Nintendo and Buffalo Technology, which allows the Nintendo DS, Wii and 3DS users without a Wi-Fi connection or compatible Wi-Fi network to establish an Internet connection via a broadband-connected PC. When inserted into the host PC's USB port, the connector functions with the Nintendo DS, Wii, DSi and 3DS, permitting the user to connect to the Internet and play Nintendo games that require a Wi-Fi connection and access various other online services. According to the official Nintendo website, this product was the best-selling Nintendo accessory to date on 15 November 2007, but was discontinued in the same month. On September 9, 2005, Nintendo announced the Nintendo Wi-Fi Network Adapter, an 802.11g wireless router/bridge which serves a similar purpose.
Functionality
The Nintendo Wi-Fi USB Connector is essentially a re-branded version of the Buffalo WLI-U2-KG54-YB. The Buffalo WLI-U2-KG54-YB is often confused for the Buffalo WLI-U2-KG54-AI because the two adapters are almost identical, and only differ in that the Buffalo WLI-U2-KG54-AI features flash memory to allow for auto installation. Both are based on the Ralink RT2570 chipset. This differentiated the Nintendo Wi-Fi USB Connector from most other Wi-Fi adapters as it could operate as a software access point (also known as a soft AP). At the time of the Nintendo Wi-Fi USB Connector's release, few Wi-Fi adapters could do this on the Windows operating system as Windows lacked both the software necessary to configure a soft AP and capable drivers that were natively supported by hardware. By bundling a soft AP compatible device with their own proprietary software, Nintendo was able to overcome the limitations of Windows and simplified the otherwise complicated process of putting a supported device into soft AP mode, configuring it, and routing Internet traffic over it.
Additionally, a number of community development tools and drivers exist whi
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https://en.wikipedia.org/wiki/Saccheri%20quadrilateral
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A Saccheri quadrilateral is a quadrilateral with two equal sides perpendicular to the base. It is named after Giovanni Gerolamo Saccheri, who used it extensively in his 1733 book (Euclid freed of every flaw), an attempt to prove the parallel postulate using the method reductio ad absurdum. Such a quadrilateral is sometimes called a Khayyam–Saccheri quadrilateral to credit Persian scholar Omar Khayyam who described them in his 11th century book (Explanations of the difficulties in the postulates of Euclid).
For a Saccheri quadrilateral the legs and are equal in length and each perpendicular to the base The top is called the summit and the angles at and are called the summit angles.
The advantage of using Saccheri quadrilaterals when considering the parallel postulate is that they clearly present three mutually exclusive options: Are the summit angles right angles, obtuse angles, or acute angles?
Saccheri himself did not consider the possibility of non-Euclidean geometry and believed that both the obtuse and acute cases could be shown to be contradictory from Euclid's other postulates. He did show that the obtuse case was contradictory, but failed to properly handle the acute case.
The existence of a Saccheri quadrilateral with right angles at the summit for any base and sides is equivalent to the parallel postulate, leading to Euclidean geometry. In hyperbolic geometry, arising from the negation of the parallel postulate, the summit angles are always acute. In elliptic or spherical geometry (which require a few modifications to Euclid's other postulates), the summit angles are always obtuse.
History
While the quadrilaterals are named for Saccheri, they were considered in the works of earlier mathematicians. Saccheri's first proposition states that if two equal lines and form equal angles with the line the angles at will equal each other; a version of this statement appears in the works of the ninth century scholar Thabit ibn Qurra. Abner of Burgos's
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https://en.wikipedia.org/wiki/Dragon%20Buster
|
is a platform, action role-playing dungeon crawl game developed by Namco and released in 1984. It runs on Namco Pac-Land hardware, modified to support vertical scrolling. In Japan, the game was ported to the Family Computer (Famicom), MSX, and X68000; the latter version was later released for the Virtual Console in the same region on November 18, 2008. Dragon Buster has been ported for the PSP and is available as part of Namco Museum Battle Collection. It was followed by a Japan-only Famicom sequel, Dragon Buster II: Yami no Fūin, and was later followed by the PlayStation game Dragon Valor, which was both a remake and sequel.
The game has side-scrolling platform gameplay and an overworld map similar to the later platform games for home consoles and personal computers. Dragon Buster was also the earliest game to feature a double jump mechanic, and one of the first to use a visual health meter.
Plot
In the beginning, a prince named Clovis was born the son of the kingdom's chief bodyguard to the royal Lawrence family. As a young child, Clovis was very mischievous and undisciplined, so his father thought it might be best to place him under the care of a monk who lived in the woods far from the kingdom. Under the monk's care, Clovis began to learn various aspects of knowledge, including how to be a superior swordsman. When word reached the monk that King Lawrence's 16-year-old daughter Celia had been abducted and held by a fearsome dragon, who wished to break the kingdom's spirit and coerce the kingdom to do his bidding, Clovis felt a sense of duty to chase after the dragon and rescue Celia in the name of his father. In order to save the Princess, he trained daily with the monk and learned to withstand injury, whether cut by swords or burned by the flame and still be just as capable a fighter as ever.
Gameplay
The player must guide the hero Clovis through each round on to the castle to rescue his beloved Princess Celia. There are multiple Princess Celias in the game,
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https://en.wikipedia.org/wiki/E-social%20science
|
E-social science is a more recent development in conjunction with the wider developments in e-science. It is social science using grid computing and other information technologies to collect, process, integrate, share, and disseminate social and behavioural data.
External links
UK National Centre for e-Social Science Web Home Page
Oxford e-Social Science This project has focused on the ethical, legal and institutional factors shaping e-Science.
ReDReSS project This site provides resources for social scientists interested in using e-Social Science and e-Science tools and methodologies.
Collaboratory for Quantitative e-Social Science
Chinese e-Social Science
E-Science
Cyberinfrastructure
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https://en.wikipedia.org/wiki/Event%20monitoring
|
In computer science, event monitoring is the process of collecting, analyzing, and signaling event occurrences to subscribers such as operating system processes, active database rules as well as human operators. These event occurrences may stem from arbitrary sources in both software or hardware such as operating systems, database management systems, application software and processors. Event monitoring may use a time series database.
Basic concepts
Event monitoring makes use of a logical bus to transport event occurrences from sources to subscribers, where event sources signal event occurrences to all event subscribers and event subscribers receive event occurrences. An event bus can be distributed over a set of physical nodes such as standalone computer systems. Typical examples of event buses are found in graphical systems such as X Window System, Microsoft Windows as well as development tools such as SDT.
Event collection is the process of collecting event occurrences in a filtered event log for analysis. A filtered event log is logged event occurrences that can be of meaningful use in the future; this implies that event occurrences can be removed from the filtered event log if they are useless in the future. Event log analysis is the process of analyzing the filtered event log to aggregate event occurrences or to decide whether or not an event occurrence should be signalled. Event signalling is the process of signalling event occurrences over the event bus.
Something that is monitored is denoted the monitored object; for example, an application, an operating system, a database, hardware etc. can be monitored objects. A monitored object must be properly conditioned with event sensors to enable event monitoring, that is, an object must be instrumented with event sensors to be a monitored object. Event sensors are sensors that signal event occurrences whenever an event occurs. Whenever something is monitored, the probe effect must be managed.
Monitored object
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https://en.wikipedia.org/wiki/Seabather%27s%20eruption
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Seabather's eruption is an itching dermatitis caused by a hypersensitivity reaction to the immature nematocysts of larval-stage thimble jellyfish (Linuche unguiculata), sea anemones (Edwardsiella lineata) and other larval cnidarians. The eruption is sometimes attributed to "sea lice" or "sea ants", but sea lice (Caligidae) are crustacean parasites of fish only.
It should not be confused with swimmer's itch.
Symptoms and signs
Symptoms generally arise later after showering. It is unusual to notice the eruptions immediately. Symptoms can last from a few days up to, exceptionally, two weeks.
The reaction is identified by severe itching around small red papules 1mm to 1.5 cm in size on areas of skin that were covered by water-permeable clothing or hair during ocean swimming. Initial swimmer exposure to the free-floating larvae produces no effects, as each organism possesses only a single undeveloped nematocyst which is inactive while suspended in seawater. However, due to their microscopic size and sticky bodies, large concentrations of larvae can become trapped in minute gaps between skin and clothing or hair. Once the swimmer leaves the ocean, the organisms stuck against the skin die, and automatically discharge their nematocysts when crushed, dried out, or exposed to freshwater. This is why symptoms usually do not appear until the swimmer dries, or takes a freshwater shower, without removing the affected clothing.
Treatment
Treatment is symptomatic, with most affected using a topical anti-itch cream (diphenhydramine) and a cortisone solution (hydrocortisone).
Incidence
Seabather's eruption is common throughout the range of Linuche unguiculata in the Caribbean, Florida, Mexico, and Gulf States. Cases were first identified in Brazil in 2001. The closely related Linuche aquila, found anywhere between Malaysia, the Philippines and the east coast of Africa, is also known to cause the condition.
Swimmers in Queensland, Australia, have reported seabather's eruptio
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https://en.wikipedia.org/wiki/Autoimmune%20hemolytic%20anemia
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Autoimmune hemolytic anemia (AIHA) occurs when antibodies directed against the person's own red blood cells (RBCs) cause them to burst (lyse), leading to an insufficient number of oxygen-carrying red blood cells in the circulation. The lifetime of the RBCs is reduced from the normal 100–120 days to just a few days in serious cases. The intracellular components of the RBCs are released into the circulating blood and into tissues, leading to some of the characteristic symptoms of this condition. The antibodies are usually directed against high-incidence antigens, therefore they also commonly act on allogenic RBCs (RBCs originating from outside the person themselves, e.g. in the case of a blood transfusion). AIHA is a relatively rare condition, with an incidence of 5–10 cases per 1 million persons per year in the warm-antibody type and 0.45 to 1.9 cases per 1 million persons per year in the cold antibody type. Autoimmune hemolysis might be a precursor of later onset systemic lupus erythematosus.
The terminology used in this disease is somewhat ambiguous. Although MeSH uses the term "autoimmune hemolytic anemia", some sources prefer the term "immunohemolytic anemia" so drug reactions can be included in this category. The National Cancer Institute considers "immunohemolytic anemia", "autoimmune hemolytic anemia", and "immune complex hemolytic anemia" to all be synonyms.
Signs and symptoms
Symptoms of AIHA may be due to the underlying anemia; including shortness of breath or dyspnea, fatigue, headache, muscle weakness and pallor. In cold agglutinin disease (cold antibody type), agglutination and impaired passage of red blood cells through capillaries in the extremities causes acrocyanosis and Raynaud phenomenon with a rare complication of gangrene
Spherocytes are found in immunologically mediated hemolytic anemias. Signs of hemolysis that are present in AIHA include low hemoglobin (blood count), alterations in levels of cell markers of hemolysis; including elevated la
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https://en.wikipedia.org/wiki/Argan%20oil
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Argan oil is a plant oil produced from the kernels of the argan tree (Argania spinosa L.), which is indigenous to Morocco and southwestern Algeria. In Morocco, argan oil is used to dip bread in at breakfast or to drizzle on couscous or pasta. It is also used for cosmetic purposes.
Properties
99% of argan oil consists of triglycerides and related derivatives. These are derived from the following fatty acids:
Argan oil has a relative density at ranging from 0.906 to 0.919.
Argan oil also contains traces of tocopherols (vitamin E), phenols, carotenes, squalene. Some trace phenols in argan oil include caffeic acid, oleuropein, vanillic acid, tyrosol, catechol, resorcinol, (−)-epicatechin and (+)-catechin.
Depending on the extraction method, argan oil may be more resistant to oxidation than olive oil.
Uses
Culinary
In Morocco, the oil is used for culinary purposes, e.g. dipping bread, as salad dressing or on couscous. Amlu, a thick brown paste with a consistency similar to peanut butter, is used locally as a bread dip. It is produced by grinding roasted almonds and argan oil together using stones, and then mixing the paste with honey.
Cosmetics
Since the early 2000s argan oil has been increasingly used in cosmetics and hair care preparations. , the main cosmetics products containing argan oil are face creams, lip glosses, shampoos, moisturizers, and soaps.
Extraction
The argan nut contains one to three oil-rich argan kernels. Extraction yields from 30% to 50% of the oil in the kernels, depending on the method. It takes about of dried argan fruit to produce only one litre of oil.
Extraction is key to the production process. To extract the kernels, workers first dry argan fruit in the open air and then remove the fleshy pulp. Some producers remove the flesh mechanically without drying the fruit. Moroccans usually use the flesh as animal feed. A tradition in some areas of Morocco allows goats to climb argan trees to feed freely on the fruits. The kernels
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https://en.wikipedia.org/wiki/Technical%20illustration
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Technical Illustration is illustration meant to visually communicate information of a technical nature. Technical illustrations can be components of technical drawings or diagrams. Technical illustrations in general aim "to generate expressive images that effectively convey certain information via the visual channel to the human observer".
Technical illustrations generally have to describe and explain the subjects to a nontechnical audience. Therefore, the visual image should be accurate in terms of dimensions and proportions, and should provide "an overall impression of what an object is or does, to enhance the viewer’s interest and understanding".
Types
Types of communication
Today, technical illustration can be broken down into three categories based on the type of communication:
Communication with the general public: informs the general public, for example illustrated instructions found in the manuals for automobiles and consumer electronics. This type of technical illustration contains simple terminology and symbols that can be understood by the lay person and is sometimes called creative technical illustration/graphics.
Specialized engineering or scientific communication: used by engineers/scientists to communicate with their peers and in specifications. This use of technical illustration has its own complex terminology and specialized symbols; examples are the fields of atomic energy, aerospace and military/defense. These areas can be further broken down into disciplines of mechanical, electrical, architectural engineering and many more.
Communication between highly skilled experts: used by engineers to communicate with people who are highly skilled in a field, but who are not engineers. Examples of this type of technical illustration are illustrations found in user/operator documentation. These illustrations can be very complex and have jargon and symbols not understood by the general public, such as illustrations that are part of instructional materi
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https://en.wikipedia.org/wiki/Spectrum%20of%20a%20theory
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In model theory, a branch of mathematical logic, the spectrum of a theory
is given by the number of isomorphism classes of models in various cardinalities. More precisely,
for any complete theory T in a language we write I(T, κ) for the number of models of T (up to isomorphism) of cardinality κ. The spectrum problem is to describe the possible behaviors of I(T, κ) as a function of κ. It has been almost completely solved for the case of a countable theory T.
Early results
In this section T is a countable complete theory and κ is a cardinal.
The Löwenheim–Skolem theorem shows that if I(T,κ) is nonzero for one infinite cardinal then it is nonzero for all of them.
Morley's categoricity theorem was the first main step in solving the spectrum problem: it states that if I(T,κ) is 1 for some uncountable κ then it is 1 for all uncountable κ.
Robert Vaught showed that I(T,ℵ0) cannot be 2. It is easy to find examples where it is any given non-negative integer other than 2. Morley proved that if I(T,ℵ0) is infinite then it must be ℵ0 or ℵ1 or 2ℵ0. It is not known if it can be ℵ1 if the continuum hypothesis is false: this is called the Vaught conjecture and is the main remaining open problem (in 2005) in the theory of the spectrum.
Morley's problem was a conjecture (now a theorem) first proposed by Michael D. Morley that I(T,κ) is nondecreasing in κ for uncountable κ. This was proved by Saharon Shelah. For this, he proved a very deep dichotomy theorem.
Saharon Shelah gave an almost complete solution to the spectrum problem. For a given complete theory T, either I(T,κ) = 2κ for all uncountable cardinals κ, or for all ordinals ξ (See Aleph number and Beth number for an explanation of the notation), which is usually much smaller than the bound in the first case. Roughly speaking this means that either there are the maximum possible number of models in all uncountable cardinalities, or there are only "few" models in all uncountable cardinalities. Shelah also gave a de
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https://en.wikipedia.org/wiki/Stretch%20shortening%20cycle
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A stretch-shortening cycle (SSC) is an active stretch (eccentric contraction) of a muscle followed by an immediate shortening (concentric contraction) of that same muscle.
Research studies
The increased performance benefit associated with muscle contractions that take place during SSCs has been the focus of much research in order to determine the true nature of this enhancement. At present, there is some debate as to where and how this performance enhancement takes place. It has been postulated that elastic structures in series with the contractile component can store energy like a spring after being forcibly stretched. Since the length of the tendon increases due to the active stretch phase, if the series elastic component acts as a spring, it would therefore be storing more potential energy. This energy would be released as the tendon shortened. Thus, the recoil of the tendon during the shortening phase of the movement would result in a more efficient movement than one in which no energy had been stored. This research is further supported by Roberts et al.
However, other studies have found that removing portions of these series-elastic components (by way of tendon length reduction) had little effect on muscle performance.
Studies on turkeys have, nevertheless, shown that during SSC, a performance enhancement associated with elastic energy storage still takes place but it is thought that the aponeurosis could be a major source of energy storage (Roleveld et al., 1994).
The contractile component itself has also been associated with the ability to increase contractile performance through muscle potentiation
while other studies have found that this ability is quite limited and unable to account for such enhancements (Lensel and Goubel, 1987, Lensel-Corbeil and Goubel, 1990; Ettema and Huijing, 1989).
Community agreement
The results of these often contradictory studies have been associated with improved efficiencies for human or animal movements such as counter
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https://en.wikipedia.org/wiki/Two%20dots%20%28diacritic%29
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Diacritical marks of two dots , placed side-by-side over or under a letter, are used in a number of languages for several different purposes. The most familiar to English-language speakers are the diaeresis and the umlaut, though there are numerous others. For example, in Albanian, represents a schwa. Such dots are also sometimes used for stylistic reasons (as in the family name Brontë or the band name Mötley Crüe).
In modern computer systems using Unicode, the two-dot diacritics are almost always encoded identically, having the same code point. For example, represents both a-umlaut and a-diaeresis. Their appearance in print or on screen may vary between typefaces but rarely within the same typeface.
Uses
Diaeresis
The "diaeresis" diacritic is used to mark the separation of two distinct vowels in adjacent syllables when an instance of diaeresis (or hiatus) occurs, so as to distinguish from a digraph or diphthong. For example, in the spelling "coöperate", the diaeresis reminds the reader that the word has four syllables co-op-er-ate, not three. It is used in several languages of western and southern Europe, though rarely now in English.
Umlaut
The "umlaut" diacritic indicates a sound shift phenomenon also known as umlaut in which a back vowel becomes a front vowel. It is a specific phenomenon in German and other Germanic languages, affecting the graphemes , , and , which are modified to , , and .
Stylistic use
The two dot diacritic is also sometimes used for purely stylistic reasons. For example, the Brontë family, whose surname was derived from gaelic and had been anglicised as "Prunty", or "Brunty": At some point, the father of the sisters, Patrick Brontë (born Brunty), decided on the alternative spelling with a diaeresis diacritic over the terminal to indicate that the name had two syllables.
Similarly the "metal umlaut" is a diacritic that is sometimes used gratuitously or decoratively over letters in the names of hard rock or heavy metal bandsfor ex
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https://en.wikipedia.org/wiki/Parasitic%20structure
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In a semiconductor device, a parasitic structure is a portion of the device that resembles in structure some other, simpler semiconductor device, and causes the device to enter an unintended mode of operation when subjected to conditions outside of its normal range. For example, the internal structure of an NPN bipolar transistor resembles two P-N junction diodes connected together by a common anode. In normal operation the base-emitter junction does indeed form a diode, but in most cases it is undesirable for the base-collector junction to behave as a diode. If a sufficient forward bias is placed on this junction it will form a parasitic diode structure, and current will flow from base to collector.
A common parasitic structure is that of a silicon controlled rectifier (SCR). Once triggered, an SCR conducts for as long as there is a current, necessitating a complete power-down to reset the behavior of the device. This condition is known as latchup.
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https://en.wikipedia.org/wiki/Friendly%20number
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In number theory, friendly numbers are two or more natural numbers with a common abundancy index, the ratio between the sum of divisors of a number and the number itself. Two numbers with the same "abundancy" form a friendly pair; n numbers with the same "abundancy" form a friendly n-tuple.
Being mutually friendly is an equivalence relation, and thus induces a partition of the positive naturals into clubs (equivalence classes) of mutually "friendly numbers".
A number that is not part of any friendly pair is called solitary.
The "abundancy" index of n is the rational number σ(n) / n, in which σ denotes the sum of divisors function. A number n is a "friendly number" if there exists m ≠ n such that σ(m) / m = σ(n) / n. "Abundancy" is not the same as abundance, which is defined as σ(n) − 2n.
"Abundancy" may also be expressed as where denotes a divisor function with equal to the sum of the k-th powers of the divisors of n.
The numbers 1 through 5 are all solitary. The smallest "friendly number" is 6, forming for example, the "friendly" pair 6 and 28 with "abundancy" σ(6) / 6 = (1+2+3+6) / 6 = 2, the same as σ(28) / 28 = (1+2+4+7+14+28) / 28 = 2. The shared value 2 is an integer in this case but not in many other cases. Numbers with "abundancy" 2 are also known as perfect numbers. There are several unsolved problems related to the "friendly numbers".
In spite of the similarity in name, there is no specific relationship between the friendly numbers and the amicable numbers or the sociable numbers, although the definitions of the latter two also involve the divisor function.
Examples
As another example, 30 and 140 form a friendly pair, because 30 and 140 have the same "abundancy":
The numbers 2480, 6200 and 40640 are also members of this club, as they each have an "abundancy" equal to 12/5.
For an example of odd numbers being friendly, consider 135 and 819 ("abundancy" 16/9 (deficient)). There are also cases of even being "friendly" to odd, such as 42 and 54463
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https://en.wikipedia.org/wiki/Redundant%20code
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In computer programming, redundant code is source code or compiled code in a computer program that is unnecessary, such as:
recomputing a value that has previously been calculated and is still available,
code that is never executed (known as unreachable code),
code which is executed but has no external effect (e.g., does not change the output produced by a program; known as dead code).
A NOP instruction might be considered to be redundant code that has been explicitly inserted to pad out the instruction stream or introduce a time delay, for example to create a timing loop by "wasting time". Identifiers that are declared, but never referenced, are termed redundant declarations.
Examples
The following examples are in C.
int foo(int iX)
{
int iY = iX*2;
return iX*2;
}
The second iX*2 expression is redundant code and can be replaced by a reference to the variable iY. Alternatively, the definition int iY = iX*2 can instead be removed.
Consider:
#define min(A,B) ((A)<(B)?(A):(B))
int shorter_magnitude(int u1, int v1, int u2, int v2)
{
/* Returns the shorter magnitude of (u1,v1) and (u2,v2) */
return sqrt(min(u1*u1 + v1*v1, u2*u2 + v2*v2));
}
As a consequence of using the C preprocessor, the compiler will only see the expanded form:
int shorter_magnitude(int u1, int v1, int u2, int v2)
{
int temp;
if (u1*u1 + v1*v1 < u2*u2 + v2*v2)
temp = u1*u1 + v1*v1; /* Redundant already calculated for comparison */
else
temp = u2*u2 + v2*v2; /* Redundant already calculated for comparison */
return sqrt(temp);
}
Because the use of min/max macros is very common, modern compilers are programmed to recognize and eliminate redundancy caused by their use.
There is no redundancy, however, in the following code:
#define max(A,B) ((A)>(B)?(A):(B))
int random(int cutoff, int range)
{
return max(cutoff, rand()%range);
}
If the initial call to rand(), modulo range, is greater than or equal to cutoff, rand() will be called a seco
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https://en.wikipedia.org/wiki/Secondary%20growth
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In botany, secondary growth is the growth that results from cell division in the cambia or lateral meristems and that causes the stems and roots to thicken, while primary growth is growth that occurs as a result of cell division at the tips of stems and roots, causing them to elongate, and gives rise to primary tissue. Secondary growth occurs in most seed plants, but monocots usually lack secondary growth. If they do have secondary growth, it differs from the typical pattern of other seed plants.
The formation of secondary vascular tissues from the cambium is a characteristic feature of dicotyledons and gymnosperms. In certain monocots, the vascular tissues are also increased after the primary growth is completed but the cambium of these plants is of a different nature. In the living pteridophytes this feature is extremely rare, only occurring in Isoetes.
Lateral meristems
In many vascular plants, secondary growth is the result of the activity of the two lateral meristems, the cork cambium and vascular cambium. Arising from lateral meristems, secondary growth increases the width of the plant root or stem, rather than its length. As long as the lateral meristems continue to produce new cells, the stem or root will continue to grow in diameter. In woody plants, this process produces wood, and shapes the plant into a tree with a thickened trunk.
Because this growth usually ruptures the epidermis of the stem or roots, plants with secondary growth usually also develop a cork cambium. The cork cambium gives rise to thickened cork cells to protect the surface of the plant and reduce water loss. If this is kept up over many years, this process may produce a layer of cork. In the case of the cork oak it will yield harvestable cork.
In nonwoody plants
Secondary growth also occurs in many nonwoody plants, e.g. tomato, potato tuber, carrot taproot and sweet potato tuberous root. A few long-lived leaves also have secondary growth.
Abnormal secondary growth
Abnormal seco
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https://en.wikipedia.org/wiki/Antibonding%20molecular%20orbital
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In theoretical chemistry, an antibonding orbital is a type of molecular orbital that weakens the chemical bond between two atoms and helps to raise the energy of the molecule relative to the separated atoms. Such an orbital has one or more nodes in the bonding region between the nuclei. The density of the electrons in the orbital is concentrated outside the bonding region and acts to pull one nucleus away from the other and tends to cause mutual repulsion between the two atoms. This is in contrast to a bonding molecular orbital, which has a lower energy than that of the separate atoms, and is responsible for chemical bonds.
Diatomic molecules
Antibonding molecular orbitals (MOs) are normally higher in energy than bonding molecular orbitals. Bonding and antibonding orbitals form when atoms combine into molecules. If two hydrogen atoms are initially far apart, they have identical atomic orbitals. However, as the spacing between the two atoms becomes smaller, the electron wave functions begin to overlap. The Pauli exclusion principle prohibits any two electrons (e-) in a molecule from having the same set of quantum numbers. Therefore each original atomic orbital of the isolated atoms (for example, the ground state energy level, 1s) splits into two molecular orbitals belonging to the pair, one lower in energy than the original atomic level and one higher. The orbital which is in a lower energy state than the orbitals of the separate atoms is the bonding orbital, which is more stable and promotes the bonding of the two H atoms into H2. The higher-energy orbital is the antibonding orbital, which is less stable and opposes bonding if it is occupied. In a molecule such as H2, the two electrons normally occupy the lower-energy bonding orbital, so that the molecule is more stable than the separate H atoms.
A molecular orbital becomes antibonding when there is less electron density between the two nuclei than there would be if there were no bonding interaction at all. When
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https://en.wikipedia.org/wiki/Matrox%20Parhelia
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The Matrox Parhelia-512 is a graphics processing unit (GPU) released by Matrox in 2002. It has full support for DirectX 8.1 and incorporates several DirectX 9.0 features. At the time of its release, it was best known for its ability to drive three monitors ("Surround Gaming") and its Coral Reef tech demo.
As had happened with previous Matrox products, the Parhelia was released just before competing companies released cards that completely outperformed it. In this case it was the ATI Radeon 9700, released only a few months later. The Parhelia remained a niche product, and was Matrox's last major effort to sell into the consumer market.
Background
The Parhelia series was Matrox's attempt to return to the market after a long hiatus, their first significant effort since the G200 and G400 lines had become uncompetitive. Their other post-G400 products, G450 and G550, were cost-reduced revisions of G400 technology and were not competitive with ATI's Radeon or NVIDIA's GeForce lines with regards to 3D computer graphics.
Description
Features
The Parhelia-512 was the first GPU by Matrox to be equipped with a 256-bit memory bus, giving it an advantage over other cards of the time in the area of memory bandwidth. The "-512" suffix refers to the 512-bit ring bus. The Parhelia processor featured Glyph acceleration, where anti-aliasing of text was accelerated by the hardware.
Parhelia-512 includes 4 32×4 vertex shaders with dedicated displacement mapping engine, pixel shader array with 4 texturing unit and 5-stage pixel shader per pixel pipeline. It supports 16× fragment anti-aliasing, all of which were featured prominently in Matrox's Coral Reef technical demo.
Display controller component supports 10-bit color frame buffer (called "Gigacolor") with 10-bit 400 MHz RAMDACs on 2 RGB ports and 230 MHz RAMDAC on TV encoder port, which was an improvement over its competitors. The frame buffer is in RGBA (10:10:10:2) format, and supports full gamma correction. Dual link TMDS is
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https://en.wikipedia.org/wiki/Matrox%20G400
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The G400 is a video card made by Matrox, released in September 1999. The graphics processor contains a 2D GUI, video, and Direct3D 6.0 3D accelerator. Codenamed "Toucan", it was a more powerful and refined version of its predecessor, the G200.
Overview
The Matrox G200 graphics processor had been a successful product, competing with the various 2D & 3D combination cards available in 1998. Matrox took the technology developed from the G200 project, refined it, and essentially doubled it up to form the G400 processor. The new chip featured several new and innovative additions, such as multiple monitor output support, an all-around 32-bit rendering pipeline with high performance, further improved 2D and video acceleration, and a new 3D feature known as Environment Mapped Bump Mapping.
Internally the G400 is a 256-bit processor, using what Matrox calls a "DualBus" architecture. This is an evolution of G200's "DualBus", which had been 128-bit. A Matrox "DualBus" chip consists of twin unidirectional buses internally, each moving data into or out of the chip. This increases the efficiency and bandwidth of data flow within the chip to each of its functional units. G400's 3D engine consists of 2 parallel pixel pipelines with 1 texture unit each, providing single-pass dual-texturing capability. The Millennium G400 MAX is capable of 333 megapixels per second fillrate at its 166 MHz core clock speed. It is purely a Direct3D 6.0 accelerator and, as such, lacks support for the later hardware transform and lighting acceleration of Direct3D 7.0 cards.
The chip's external memory interface is 128-bit and is designed to use either SDRAM or SGRAM. Matrox released both 16 MiB and 32 MiB versions of the G400 boards, and used both types of RAM. The slowest models are equipped with 166 MHz SDRAM, while the fastest (G400 MAX) uses 200 MHz SGRAM. G400MAX had the highest memory bandwidth of any card before the release of the DDR-equipped version of NVIDIA GeForce 256.
Perhaps the most not
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https://en.wikipedia.org/wiki/Ring%20flip
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In organic chemistry, a ring flip (also known as a ring inversion or ring reversal) is the interconversion of cyclic conformers that have equivalent ring shapes (e.g., from a chair conformer to another chair conformer) that results in the exchange of nonequivalent substituent positions. The overall process generally takes place over several steps, involving coupled rotations about several of the molecule's single bonds, in conjunction with minor deformations of bond angles. Most commonly, the term is used to refer to the interconversion of the two chair conformers of cyclohexane derivatives, which is specifically referred to as a chair flip, although other cycloalkanes and inorganic rings undergo similar processes.
Chair flip
As stated above, a chair flip is a ring inversion specifically of cyclohexane (and its derivatives) from one chair conformer to another, often to reduce steric strain. The term, "flip" is misleading, because the direction of each carbon remains the same; what changes is the orientation. A conformation is a unique structural arrangement of atoms, in particular one achieved through the rotation of single bonds. A conformer is a conformational isomer, a blend of the two words.
Cyclohexane
There exist many different conformations for cyclohexane, such as chair, boat, and twist-boat, but the chair conformation is the most commonly observed state for cyclohexanes because it requires the least amount of energy. The chair conformation minimizes both angle strain and torsional strain by having all carbon-carbon bonds at 110.9° and all hydrogens staggered from one another.
The molecular motions involved in a chair flip are detailed in the figure on the right: The half-chair conformation (D, 10.8 kcal/mol, C2 symmetry) is the energy maximum when proceeding from the chair conformer (A, 0 kcal/mol reference, D3d symmetry) to the higher energy twist-boat conformer (B, 5.5 kcal/mol, D2 symmetry). The boat conformation (C, 6.9 kcal/mol, C2v symmetry) is a
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https://en.wikipedia.org/wiki/P-y%20method
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In geotechnical civil engineering, the p–y is a method of analyzing the ability of deep foundations to resist loads applied in the lateral direction. This method uses the finite difference method and p-y graphs to find a solution. P–y graphs are graphs which relate the force applied to soil to the lateral deflection of the soil. In essence, non-linear springs are attached to the foundation in place of the soil. The springs can be represented by the following equation:
where '' is the non-linear spring stiffness defined by the p–y curve, is the deflection of the spring, and is the force applied to the spring.
The p–y curves vary depending on soil type.
The available geotechnical engineering software programs for the p–y method include FB-MultiPier by the Bridge Software Institute, DeepFND by Deep Excavation LLC, PileLAT by Innovative Geotechnics, LPile by Ensoft, and PyPile by Yong Technology.
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https://en.wikipedia.org/wiki/Plain%20old%20CLR%20object
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In software engineering, a plain old CLR object, or plain old class object (POCO) is a simple object created in the .NET Common Language Runtime (CLR) that is unencumbered by inheritance or attributes. This is often used in opposition to the complex or specialized objects that object-relational mapping frameworks often require. In essence, a POCO does not have any dependency on an external framework.
Etymology
Plain Old CLR Object is a play on the term plain old Java object from the Java EE programming world, which was coined by Martin Fowler in 2000. POCO is often expanded to plain old C# object, though POCOs can be created with any language targeting the CLR. An alternative acronym sometimes used is plain old .NET object.
Benefits
Some benefits of POCOs are:
allows a simple storage mechanism for data, and simplifies serialization and passing data through layers;
goes hand-in-hand with dependency injection and the repository pattern;
minimised complexity and dependencies on other layers (higher layers only care about the POCOs, POCOs don't care about anything) which facilitates loose coupling;
increases testability through simplification.
See also
Plain old data structure
Plain old Java object
Data transfer object
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https://en.wikipedia.org/wiki/JavaScript%20syntax
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The syntax of JavaScript is the set of rules that define a correctly structured JavaScript program.
The examples below make use of the log function of the console object present in most browsers for standard text output.
The JavaScript standard library lacks an official standard text output function (with the exception of document.write). Given that JavaScript is mainly used for client-side scripting within modern web browsers, and that almost all Web browsers provide the alert function, alert can also be used, but is not commonly used.
Origins
Brendan Eich summarized the ancestry of the syntax in the first paragraph of the JavaScript 1.1 specification as follows:
Basics
Case sensitivity
JavaScript is case sensitive. It is common to start the name of a constructor with a capitalised letter, and the name of a function or variable with a lower-case letter.
Example:
var a = 5;
console.log(a); // 5
console.log(A); // throws a ReferenceError: A is not defined
Whitespace and semicolons
Unlike in C, whitespace in JavaScript source can directly impact semantics. Semicolons end statements in JavaScript. Because of automatic semicolon insertion (ASI), some statements that are well formed when a newline is parsed will be considered complete, as if a semicolon were inserted just prior to the newline. Some authorities advise supplying statement-terminating semicolons explicitly, because it may lessen unintended effects of the automatic semicolon insertion.
There are two issues: five tokens can either begin a statement or be the extension of a complete statement; and five restricted productions, where line breaks are not allowed in certain positions, potentially yielding incorrect parsing.
The five problematic tokens are the open parenthesis "(", open bracket "[", slash "/", plus "+", and minus "-". Of these, the open parenthesis is common in the immediately invoked function expression pattern, and open bracket occurs sometimes, while others are quite rare. An example:
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https://en.wikipedia.org/wiki/Speed%20Dependent%20Damping%20Control
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Speed Dependent Damping Control (also called SD²C) was an automatic damper system installed on late-1980s and early-1990s Cadillac automobiles. This system firmed up the suspension at 25 mph (40 km/h) and again at 60 mph (97 km/h). The firmest setting was also used when starting from a standstill until 5 mph (8 km/h).
Applications:
1989–1992 Cadillac Allanté
Computer Command Ride
The semi-active suspension system was updated as Computer Command Ride in 1991. This new system included acceleration, braking rates, and lateral acceleration to the existing vehicle speed metric.
1991– Cadillac Fleetwood
1991– Cadillac Eldorado
1991– Cadillac Seville
1991– Cadillac De Ville (optional, standard for 1993)
1992– Oldsmobile Achieva SCX W41
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https://en.wikipedia.org/wiki/High%20availability
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High availability (HA) is a characteristic of a system that aims to ensure an agreed level of operational performance, usually uptime, for a higher than normal period.
Modernization has resulted in an increased reliance on these systems. For example, hospitals and data centers require high availability of their systems to perform routine daily activities. Availability refers to the ability of the user community to obtain a service or good, access the system, whether to submit new work, update or alter existing work, or collect the results of previous work. If a user cannot access the system, it is – from the user's point of view – unavailable. Generally, the term downtime is used to refer to periods when a system is unavailable.
Resilience
High availability is a property of network resilience, the ability to "provide and maintain an acceptable level of service in the face of faults and challenges to normal operation." Threats and challenges for services can range from simple misconfiguration over large scale natural disasters to targeted attacks. As such, network resilience touches a very wide range of topics. In order to increase the resilience of a given communication network, the probable challenges and risks have to be identified and appropriate resilience metrics have to be defined for the service to be protected.
The importance of network resilience is continuously increasing, as communication networks are becoming a fundamental component in the operation of critical infrastructures. Consequently, recent efforts focus on interpreting and improving network and computing resilience with applications to critical infrastructures. As an example, one can consider as a resilience objective the provisioning of services over the network, instead of the services of the network itself. This may require coordinated response from both the network and from the services running on top of the network.
These services include:
supporting distributed processing
supportin
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https://en.wikipedia.org/wiki/Vapor%20recovery
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Vapor (or vapour) recovery is the process of collecting the vapors of gasoline and other fuels, so that they do not escape into the atmosphere. This is often done (and sometimes required by law) at filling stations, to reduce noxious and potentially explosive fumes and pollution.
The negative pressure created by a vacuum pump typically located in the fuel dispenser, combined with the pressure in the car's fuel tank caused by the inflow, is usually used to pull in the vapors. They are drawn in through holes in the side of the nozzle and travel along a return path through another hose.
In 1975 the Vapor Recovery Gasoline Nozzle was an improvement on the idea of the original gasoline nozzle delivery system.
The improved idea was the brain child of Mark Maine of San Diego, California, where Mark was a gas station attendant at a corporate owned and operated Chevron U.S.A. service station. The story is, after watching the tanker truck driver deliver gasoline to the station using two hoses, one to deliver the gasoline from the tanker, and the other hose to recover the escaping gasoline vapors back into the emptying tanker. Mark talked with the driver to understand why the two hose system was used, and also why is was not implemented on the standard delivery nozzle, allowing vapors to escape from the vehicle gas tank. After the tanker driver left, Mark drew an idea for a Vapor Recovery Gasoline Nozzle and submitted it to the Chevron Station Management as an employee suggestion.
Mark was included in the design and development as the original Vapor recovery gasoline nozzle, which was manufactured and delivered by Huddleson. Mark was also promoted from the Chevron Service Station to an executive position based out of the Corporate in La Habra, California. Mark was appointed as the Vapor Recovery Gasoline Nozzle executive for the 2 year implementation program, his duties were to train and oversee the installation and maintenance of 124 Chevron Service Stations within San Di
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https://en.wikipedia.org/wiki/Richard%20M.%20Dudley
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Richard Mansfield Dudley (July 28, 1938 – January 19, 2020) was Professor of Mathematics at the Massachusetts Institute of Technology.
Education and career
Dudley was born in Cleveland, Ohio. He earned his BA at Harvard College and received his PhD at Princeton University in 1962 under the supervision of Edward Nelson and Gilbert Hunt. He was a Putnam Fellow in 1958. He was an instructor and assistant professor at University of California, Berkeley between 1962 and 1967, before moving to MIT as a professor in mathematics, where he stayed from 1967 until 2015, when he retired.
He died on January 19, 2020, following a long illness.
Research
His work mainly concerned fields of probability, mathematical statistics, and machine learning, with highly influential contributions to the theory of Gaussian processes and empirical processes. He published over a hundred papers in peer-reviewed journals and authored several books. His specialty was probability theory and statistics, especially empirical processes. He is often noted for his results on the so-called Dudley entropy integral. In 2012 he became a fellow of the American Mathematical Society.
Books
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https://en.wikipedia.org/wiki/Air%20gap%20%28networking%29
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An air gap, air wall, air gapping or disconnected network is a network security measure employed on one or more computers to ensure that a secure computer network is physically isolated from unsecured networks, such as the public Internet or an unsecured local area network. It means a computer or network has no network interface controllers connected to other networks, with a physical or conceptual air gap, analogous to the air gap used in plumbing to maintain water quality.
Use in classified settings
An air-gapped computer or network is one that has no network interfaces, either wired or wireless, connected to outside networks. Many computers, even when they are not plugged into a wired network, have a wireless network interface controller (WiFi) and are connected to nearby wireless networks to access the Internet and update software. This represents a security vulnerability, so air-gapped computers either have their wireless interface controller permanently disabled or physically removed. To move data between the outside world and the air-gapped system, it is necessary to write data to a physical medium such as a thumbdrive, and physically move it between computers. Physical access has to be controlled (man identity and storage media itself). It is easier to control than a direct full network interface, which can be attacked from the exterior insecure system and, if malware infects the secure system, can be used to export secure data. That's why some new hardware technologies are also available like unidirectional data diodes or bidirectional diodes (also called electronic airgaps), that physically separate the network and transportation layers and copy and filter the application data.
In environments where networks or devices are rated to handle different levels of classified information, the two disconnected devices or networks are referred to as low side and high side, low being unclassified and high referring to classified, or classified at a higher
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https://en.wikipedia.org/wiki/Trace%20vector%20decoder
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A Trace Vector Decoder (TVD) is computer software that uses the trace facility of its underlying microprocessor to decode encrypted instruction opcodes just-in-time prior to execution and possibly re-encode them afterwards. It can be used to hinder reverse engineering when attempting to prevent software cracking as part of an overall copy protection strategy.
Microprocessor tracing
Certain microprocessor families (e.g. 680x0, x86) provide the capability to trace instructions to aid in program development. A debugger might use this capability to single step through a program, providing the means for a programmer to monitor the execution of the program under test.
By installing a custom handler for the trace exception, it is possible to gain control of the microprocessor between the execution of normal program flow instructions. A typical trace vector decoder exception handler decodes the upcoming instruction located outside the exception, as well as re-encoding the previously decoded instruction.
Implementations
Motorola 680x0
The Motorola 68000 has an instruction-by-instruction tracing facility. When its trace state is enabled, the processor automatically forces a trace exception after each (non-exception) instruction is executed. The following assembly code snippet is an example of a program initializing a trace exception handler on a 68000 system.
InstallHandler: MOVE.L #$4E730000,-(SP) ; Push trace exception handler on to stack
MOVE.L #$00000010,-(SP)
MOVE.L #$0004DDB9,-(SP)
MOVE.L #$BD96BDAE,-(SP)
MOVE.L #$B386B586,-(SP)
MOVE.L #$D046D246,-(SP)
MOVE.L #$0246A71F,-(SP)
MOVE.L #$00023C17,-(SP)
MOVE.W #$2C6F,-(SP)
MOVE.L SP,($24).W ; Set trace exception handler vector
ORI.W #$A71F,SR ; Enable trace state
NOP ; CPU generates a trace
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https://en.wikipedia.org/wiki/Cake%20number
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In mathematics, the cake number, denoted by Cn, is the maximum of the number of regions into which a 3-dimensional cube can be partitioned by exactly n planes. The cake number is so-called because one may imagine each partition of the cube by a plane as a slice made by a knife through a cube-shaped cake. It is the 3D analogue of the lazy caterer's sequence.
The values of Cn for are given by .
General formula
If n! denotes the factorial, and we denote the binomial coefficients by
and we assume that n planes are available to partition the cube, then the n-th cake number is:
Properties
The only cake number which is prime is 2, since it requires to have prime factorisation where is some prime. This is impossible for as we know must be even, so it must be equal to , , , or , which correspond to the cases: (which has only complex roots), (i.e. ), , and .
The cake numbers are the 3-dimensional analogue of the 2-dimensional lazy caterer's sequence. The difference between successive cake numbers also gives the lazy caterer's sequence.
The fourth column of Bernoulli's triangle (k = 3) gives the cake numbers for n cuts, where n ≥ 3.
The sequence can be alternatively derived from the sum of up to the first 4 terms of each row of Pascal's triangle:
{| class="wikitable" style="text-align:right;"
! !! 0 !! 1 !! 2 !! 3
! rowspan="11" style="padding:0;"| !! Sum
|-
! style="text-align:left;"|1
| 1 || — || — || — || 1
|-
! style="text-align:left;"|2
| 1 || 1 || — || — || 2
|-
! style="text-align:left;"|3
| 1 || 2 || 1 || — || 4
|-
! style="text-align:left;"|4
| 1 || 3 || 3 || 1 || 8
|-
! style="text-align:left;"|5
| 1 || 4 || 6 || 4 || 15
|-
! style="text-align:left;"|6
| 1 || 5 || 10 || 10 || 26
|-
! style="text-align:left;"|7
| 1 || 6 || 15 || 20 || 42
|-
! style="text-align:left;"|8
| 1 || 7 || 21 || 35 || 64
|-
! style="text-align:left;"|9
| 1 || 8 || 28 || 56 || 93
|-
! style="text-align:left;"|10
| 1 || 9 || 36 || 84 || 130
|}
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https://en.wikipedia.org/wiki/Maclaurin%20spheroid
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A Maclaurin spheroid is an oblate spheroid which arises when a self-gravitating fluid body of uniform density rotates with a constant angular velocity. This spheroid is named after the Scottish mathematician Colin Maclaurin, who formulated it for the shape of Earth in 1742. In fact the figure of the Earth is far less oblate than Maclaurin's formula suggests, since the Earth is not homogeneous, but has a dense iron core. The Maclaurin spheroid is considered to be the simplest model of rotating ellipsoidal figures in hydrostatic equilibrium since it assumes uniform density.
Maclaurin formula
For a spheroid with equatorial semi-major axis and polar semi-minor axis , the angular velocity about is given by Maclaurin's formula
where is the eccentricity of meridional cross-sections of the spheroid, is the density and is the gravitational constant. The formula predicts two possible equilibrium figures when , one is a sphere () and the other is a very flattened spheroid (). The maximum angular velocity occurs at eccentricity and its value is , so that above this speed, no equilibrium figures exist. The angular momentum is
where is the mass of the spheroid and is the mean radius, the radius of a sphere of the same volume as the spheroid.
Stability
For a Maclaurin spheroid of eccentricity greater than 0.812670, a Jacobi ellipsoid of the same angular momentum has lower total energy. If such a spheroid is composed of a viscous fluid, and if it suffers a perturbation which breaks its rotational symmetry, then it will gradually elongate into the Jacobi ellipsoidal form, while dissipating its excess energy as heat. This is termed secular instability. However, for a similar spheroid composed of an inviscid fluid, the perturbation will merely result in an undamped oscillation. This is described as dynamic (or ordinary) stability.
A Maclaurin spheroid of eccentricity greater than 0.952887 is dynamically unstable. Even if it is composed of an inviscid fluid and h
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https://en.wikipedia.org/wiki/Block%20walking
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In combinatorial mathematics, block walking is a method useful in thinking about sums of combinations graphically as "walks" on Pascal's triangle. As the name suggests, block walking problems involve counting the number of ways an individual can walk from one corner A of a city block to another corner B of another city block given restrictions on the number of blocks the person may walk, the directions the person may travel, the distance from A to B, et cetera.
An example block walking problem
Suppose such an individual, say "Fred", must walk exactly k blocks to get to a point B that is exactly k blocks from A. It is convenient to regard Fred's starting point A as the origin, , of a rectangular array of lattice points and B as some lattice point , e units "East" and n units "North" of A, where and both and are nonnegative.
Solution by brute force
A "brute force" solution to this problem may be obtained by systematically counting the number of ways Fred can reach each point where
and
without backtracking (i.e. only traveling North or East from one point to another) until a pattern is observed. For example, the number of ways Fred could go from to or is exactly one; to is two; to or is one; to or is three; and so on. Actually, you could receive the number of ways to get to a particular point by adding up the number of ways you can get to the point south of it and the number of ways you can get to the point west of it.(With the starting point being zero and all the points directly north and south of it one.) In general, one soon discovers that the number of paths from A to any such X corresponds to an entry of Pascal's Triangle.
Combinatorial solution
Since the problem involves counting a finite, discrete number of paths between lattice points, it is reasonable to assume a combinatorial solution exists to the problem. Towards this end, we note that for Fred to still be on a path that will take him from A to B over blocks, at any point X he must ei
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https://en.wikipedia.org/wiki/Epistemic%20modal%20logic
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Epistemic modal logic is a subfield of modal logic that is concerned with reasoning about knowledge. While epistemology has a long philosophical tradition dating back to Ancient Greece, epistemic logic is a much more recent development with applications in many fields, including philosophy, theoretical computer science, artificial intelligence, economics and linguistics. While philosophers since Aristotle have discussed modal logic, and Medieval philosophers such as Avicenna, Ockham, and Duns Scotus developed many of their observations, it was C. I. Lewis who created the first symbolic and systematic approach to the topic, in 1912. It continued to mature as a field, reaching its modern form in 1963 with the work of Kripke.
Historical development
Many papers were written in the 1950s that spoke of a logic of knowledge in passing, but the Finnish philosopher G. H. von Wright's 1951 paper titled An Essay in Modal Logic is seen as a founding document. It was not until 1962 that another Finn, Hintikka, would write Knowledge and Belief, the first book-length work to suggest using modalities to capture the semantics of knowledge rather than the alethic statements typically discussed in modal logic. This work laid much of the groundwork for the subject, but a great deal of research has taken place since that time. For example, epistemic logic has been combined recently with some ideas from dynamic logic to create dynamic epistemic logic, which can be used to specify and reason about information change and exchange of information in multi-agent systems. The seminal works in this field are by Plaza, Van Benthem, and Baltag, Moss, and Solecki.
Standard possible worlds model
Most attempts at modeling knowledge have been based on the possible worlds model. In order to do this, we must divide the set of possible worlds between those that are compatible with an agent's knowledge, and those that are not. This generally conforms with common usage. If I know that it is eithe
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https://en.wikipedia.org/wiki/Chicken%20feet
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Chicken feet are cooked and eaten in many countries. After an outer layer of hard skin is removed, most of the edible tissue on the feet consists of skin and tendons, with no muscle. This gives the feet a distinct gelatinous texture different from the rest of the chicken meat.
Around the world
China
Chicken feet are used in several regional Chinese cuisines; they can be served as a beer snack, cold dish, soup or main dish. They are interchangeably called Fèng zhuǎ (鳯爪, phoenix claws), Jī zhuǎ (鷄爪, chicken claws), and Jī jiǎo (雞脚, chicken feet).
In Guangdong and Hong Kong, they are typically deep fried and steamed first to make them puffy before being stewed and simmered in a sauce flavoured with black fermented beans, bean paste, and sugar; or in abalone sauce.
In mainland China, popular snack bars specializing in marinated food such as yabozi (duck's necks) also sell lu ji zhua (鹵雞爪, marinated chicken feet), which are simmered with soy sauce, Sichuanese peppercorn, clove, garlic, star anise, cinnamon and chili flakes. Today, packaged chicken feet are sold in most grocery stores and supermarkets in China as a snack, often seasoned with rice vinegar and chili. Another popular recipe is bai yun feng zhao (), which is marinated in a sauce of rice vinegar, rice wine flavored with sugar, salt, and minced ginger for an extended period of time and served as a cold dish. In southern China, they also cook chicken feet with raw peanuts to make a thin soup.
The huge demand in China raises the price of chicken feet, which are often used as fodder in other countries. As of June 2011, 1 kg of raw chicken feet costs around 12 to 16 yuan in China, compared to 11–12 yuan for 1 kg of frozen chicken breast. In 2000, Hong Kong, once the largest entrepôt for shipping chicken feet from over 30 countries, traded a total of 420,000 tons of chicken feet at the value of US$230 million. Two years after joining the WTO in 2001, China approved the direct import of American chicken feet,
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https://en.wikipedia.org/wiki/Calculator%20%28Apple%29
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Calculator is a basic calculator application made by Apple Inc. and bundled with its macOS, iOS, and watchOS operating systems. It has three modes: basic, scientific, and programmer. The basic mode includes a number pad, buttons for adding, subtracting, multiplying, and dividing, as well as memory keys. Scientific mode supports exponents and trigonometric functions. The macOS version of Calculator guys apple is the worst also has a programmer mode that gives the user access to more options related to computer programming.
The Calculator program has a long associated history with the beginning of the Macintosh platform, where a simple four-function calculator program was a standard desk accessory from the earliest system versions. Though no higher math capability was included, third-party developers provided upgrades, and Apple released the Graphing Calculator application with the first PowerPC release (7.1.2) of the Mac OS, and it was a standard component through Mac OS 9. Apple also ships a different application with macOS called Grapher for this purpose.
A calculator function has been included with iOS since its launch on iPhone and iPod Touch. However, iPads have never had a first party calculator application. A native calculator function was added to the Apple Watch with watchOS 6, which included a dedicated button for calculating tips.
Features
Calculator has Reverse Polish notation support, and can also speak the buttons pressed and result returned.
The calculator also includes some basic conversion functions to convert between units in the following categories:
Area
Currency (exchange rates may be updated over the Internet)
Energy or Work
Temperature
Length
Speed
Pressure
Weight/Mass
Power
Volume
Since the release of Mac OS X Leopard, simple arithmetic functions can be calculated from the Spotlight feature. They include the standard addition, subtraction, multiplication, and division operations, with exponentiation and the use of the percent sign to denot
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https://en.wikipedia.org/wiki/Glivenko%E2%80%93Cantelli%20theorem
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In the theory of probability, the Glivenko–Cantelli theorem (sometimes referred to as the Fundamental Theorem of Statistics), named after Valery Ivanovich Glivenko and Francesco Paolo Cantelli, determines the asymptotic behaviour of the empirical distribution function as the number of independent and identically distributed observations grows.
The uniform convergence of more general empirical measures becomes an important property of the Glivenko–Cantelli classes of functions or sets. The Glivenko–Cantelli classes arise in Vapnik–Chervonenkis theory, with applications to machine learning. Applications can be found in econometrics making use of M-estimators.
Statement
Assume that are independent and identically distributed random variables in with common cumulative distribution function . The empirical distribution function for is defined by
where is the indicator function of the set For every (fixed) is a sequence of random variables which converge to almost surely by the strong law of large numbers. Glivenko and Cantelli strengthened this result by proving uniform convergence of to
Theorem
almost surely.
This theorem originates with Valery Glivenko and Francesco Cantelli, in 1933.
Remarks
If is a stationary ergodic process, then converges almost surely to The Glivenko–Cantelli theorem gives a stronger mode of convergence than this in the iid case.
An even stronger uniform convergence result for the empirical distribution function is available in the form of an extended type of law of the iterated logarithm. See asymptotic properties of the empirical distribution function for this and related results.
Proof
For simplicity, consider a case of continuous random variable . Fix such that for . Now for all there exists such that . Note that
Therefore,
Since by strong law of large numbers, we can guarantee that for any positive and any integer such that , we can find such that for all , we have . Combined with the above result,
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https://en.wikipedia.org/wiki/Donsker%27s%20theorem
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In probability theory, Donsker's theorem (also known as Donsker's invariance principle, or the functional central limit theorem), named after Monroe D. Donsker, is a functional extension of the central limit theorem.
Let be a sequence of independent and identically distributed (i.i.d.) random variables with mean 0 and variance 1. Let . The stochastic process is known as a random walk. Define the diffusively rescaled random walk (partial-sum process) by
The central limit theorem asserts that converges in distribution to a standard Gaussian random variable as . Donsker's invariance principle extends this convergence to the whole function . More precisely, in its modern form, Donsker's invariance principle states that: As random variables taking values in the Skorokhod space , the random function converges in distribution to a standard Brownian motion as
Formal statement
Let Fn be the empirical distribution function of the sequence of i.i.d. random variables with distribution function F. Define the centered and scaled version of Fn by
indexed by x ∈ R. By the classical central limit theorem, for fixed x, the random variable Gn(x) converges in distribution to a Gaussian (normal) random variable G(x) with zero mean and variance F(x)(1 − F(x)) as the sample size n grows.
Theorem (Donsker, Skorokhod, Kolmogorov) The sequence of Gn(x), as random elements of the Skorokhod space , converges in distribution to a Gaussian process G with zero mean and covariance given by
The process G(x) can be written as B(F(x)) where B is a standard Brownian bridge on the unit interval.
History and related results
Kolmogorov (1933) showed that when F is continuous, the supremum and supremum of absolute value, converges in distribution to the laws of the same functionals of the Brownian bridge B(t), see the Kolmogorov–Smirnov test. In 1949 Doob asked whether the convergence in distribution held for more general functionals, thus formulating a problem of weak converg
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https://en.wikipedia.org/wiki/Medication%20discontinuation
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Medication discontinuation is the ceasing of a medication treatment for a patient by either the clinician or the patient themself. When initiated by the clinician, it is known as deprescribing. Medication discontinuation is an important medical practice that may be motivated by a number of reasons:
Reducing polypharmacy
Reducing health expenditure
Improving quality of life by ceasing medications with potential adverse effects or where the indication for a medical treatment may have changed
Reflect changes in evidence that support a treatment
Reflecting changes in treatment goals, such as a move to end-of-life care.
Unlike the prescribing of medications, appropriate discontinuation has not attracted nearly as much attention or interest.
End-of-life care
Medications may be stopped in the context of end-of-life care, such as medications that may affect risk factors for future disease. Medications that may be stopped as part of discussions about end-of-life care include antihypertensives, medications for diabetes, and drugs for high cholesterol.
Life limiting conditions
For people with a life limiting condition such as a dementia, it is important to consider when to discontinue medications used to prevent future serious events. The Medication Appropriateness Tool for Comorbid Health conditions during Dementia (MATCH-D) provides guidance for clinicians and consumers on how to manage medications.
Effects
Drug discontinuation may cause rebound effects (return of the symptoms the drug relieved, and that, to a degree stronger than they were before treatment first began) and withdrawal syndromes (symptoms caused by the discontinuation by the drug itself).
Drug discontinuation may be difficult to adjust to, owing to the long term use and the symbolism associated with ceasing medications, such as the decision to stop chemotherapy.
Recent research (Nixon & Vendelø, 2016) shows that General Practitioners (GPs) who actively consider discontinuation, are reluctant to d
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https://en.wikipedia.org/wiki/Functional%20spinal%20unit
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A functional spinal unit (FSU) (or motion segment) is the smallest physiological motion unit of the spine to exhibit biomechanical characteristics similar to those of the entire spine.
A FSU consists of two adjacent vertebrae, the intervertebral disc and all adjoining ligaments between them and excludes other connecting tissues such as muscles. The three-joint complex that results is sometimes referred to as the "articular triad".
In vitro studies of isolated or multiple FSU's are often used to measure biomechanical properties of the spine. The typical load-displacement behavior of a cadaveric FSU specimen is nonlinear. Within the total range of passive motion of any FSU, the typical load-displacement curve consists of 2 regions or 'zones' that exhibit very different biomechanical behavior. In the vicinity of the resting neutral position of the FSU, this load-displacement behavior is highly flexible. This is the region known as the 'neutral zone', which is the motion region of the joint where the passive osteoligamentous stability mechanisms exert little or no influence. During passive physiological movement of the FSU, motion occurs in this region against minimal internal resistance. It is a region in which a small load causes a relatively large displacement. The 'elastic zone' is the remaining region of FSU motion that continues from the end of the neutral zone to the point of maximum resistance (provided by the passive osteoligamentous stability mechanism), thus limiting the range of motion.
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https://en.wikipedia.org/wiki/Human%20bonding
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Human bonding is the process of development of a close interpersonal relationship between two or more people. It most commonly takes place between family members or friends, but can also develop among groups, such as sporting teams and whenever people spend time together. Bonding is a mutual, interactive process, and is different from simple liking. It is the process of nurturing social connection.
Bonding typically refers to the process of attachment that develops between romantic or platonic partners, close friends, or parents and children. This bond is characterised by emotions such as affection and trust. Any two people who spend time together may form a bond. Male bonding refers to the establishment of relationships between men through shared activities. The term female bonding refers to the formation of close personal relationships between women. Cross-sex friendships refers to personal relationships between men and women.
Early views
In the 4th century BC, the Greek philosopher Plato argued that love directs the bonds of human society. In his Symposium, Eryximachus, one of the narrators in the dialog, states that love goes far beyond simple attraction to human beauty. He states that it occurs throughout the animal and plant kingdoms, as well as throughout the universe. Love directs everything that occurs, in the realm of the gods as well as that of humans (186a–b).
Eryximachus reasons that when various opposing elements such as wet and dry are "animated by the proper species of Love, they are in harmony with one another... But when the sort of Love that is crude and impulsive controls the seasons, he brings death and destruction" (188a). Because it is love that guides the relations between these sets of opposites throughout existence, in every case it is the higher form of love that brings harmony and cleaves toward the good, whereas the impulsive vulgar love creates disharmony.
Plato concludes that the highest form of love is the greatest. When love "is
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https://en.wikipedia.org/wiki/The%20Return%20of%20Ishtar
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is an action role-playing arcade video game released by Namco in 1986. It runs on Namco System 86 hardware and is the sequel to The Tower of Druaga, which was released two years earlier. The game's story directly starts after the first game, where Ki and Gil must venture down in the Tower of Druaga and escape it. It is the second game in the company's Babylonian Castle Saga series, and was later ported to the MSX, NEC PC-8801, FM-7, and Sharp X68000 platforms. The Return of Ishtar was included in the compilation game Namco Museum Volume 4 for the PlayStation, which is also the first time the game had been released overseas.
Gameplay
The Return of Ishtar is an adventure game that requires two players. It was also the first game from Namco to have a password feature, to give players the opportunity to continue from where they left off, and their first to not feature a scoring system. Player 1 controls the priestess Ki who fights with magic, while Player 2 controls the sword-wielding Prince Gilgamesh. This sequel starts off directly after Gilgamesh has saved Ki from Druaga, and focuses on their escape from the tower (and its inhabitants) who are after Gilgamesh and Ki to avenge their former master. There are a total of 128 rooms in the sixty-floor tower, and the screen will only scroll according to Ki's location, so the second player will have to stay close to their partner as they traverse the tower. Ki attacks by casting spells at the enemies, while Gilgamesh automatically draws his sword whenever an enemy gets close enough to him, allowing him to attack the enemy by bumping into it with his blade (similar to Adol from the Ys games). However, colliding with enemies will also damage Gilgamesh, and the counter in the bottom-right of the screen will decrease by a preset amount, depending on what enemy type it was. If the counter reaches 0, he will disappear, and the game will be over for both players (which will also happen if Ki is touched by any enemy at all). There
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https://en.wikipedia.org/wiki/Genstat
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Genstat (General Statistics) is a statistical software package with data analysis capabilities, particularly in the field of agriculture.
It was developed in 1968 by the Rothamsted Research in the United Kingdom and was designed to provide modular design, linear mixed models and graphical functions. It was developed and distributed by VSN International (VSNi), which was owned by The Numerical Algorithms Group and Rothamsted Research.
Genstat is used in a number of research areas, including plant science, forestry, animal science, and medicine.
See also
ASReml: a statistical package which fits linear mixed models to large data sets with complex variance models, using Residual Maximum Likelihood (REML)
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https://en.wikipedia.org/wiki/S-PLUS
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S-PLUS is a commercial implementation of the S programming language sold by TIBCO Software Inc.
It features object-oriented programming capabilities and advanced analytical algorithms.
Due to the increasing popularity of the open source S successor R, TIBCO Software released the TIBCO Enterprise Runtime for R (TERR) as an alternative R interpreter.
Historical timeline
1988: S-PLUS is first produced by a Seattle-based start-up company called Statistical Sciences, Inc. The founder and sole owner is R. Douglas Martin, professor of statistics at the University of Washington, Seattle.
1993: Statistical Sciences acquires the exclusive license to distribute S and merges with MathSoft, becoming the firm's Data Analysis Products Division (DAPD).
1995: S-PLUS 3.3 for Windows 95/NT. Matrix library, command history, Trellis graphics
1996: S-PLUS 3.4 for UNIX. Trellis graphics, (non-linear mixed effects) library, hexagonal binning, cluster methods.
1997: S-PLUS 4 for Windows. New GUI, integration with Excel, editable graphics.
1998: S-PLUS 4.5 for Windows. Scatterplot brushing, create S-PLUS graphs from within Excel & SPSS.
1998: S-PLUS is available for Linux & Solaris.
1999: S-PLUS 5 for Solaris, Linux, HP-UX, AIX, IRIX, and DEC Alpha. S-PLUS 2000 for Windows. 3.3, quality control charting, new commands for data manipulation.
2000: S-PLUS 6 for Linux/Unix. Java-based GUI, Graphlets, survival5, missing data library, robust library.
2001: MathSoft sells its Cambridge-based Engineering and Education Products Division (EEPD), changes name to Insightful Corporation, and moves headquarters to Seattle. This move is basically an "Undo" of the previous merger between MathSoft and Statistical Sciences, Inc.
2001: S-PLUS Analytic Server 2.0. S-PLUS 6 for Windows (Excel integration, C++ classes/libraries for connectivity, Graphlets, S version 4, missing data library, robust library).
2002: StatServer 6. Student edition of S-PLUS now free.
2003: S-PLUS 6.2 New reporting, d
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https://en.wikipedia.org/wiki/Fungal%20prion
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A fungal prion is a prion that infects hosts which are fungi. Fungal prions are naturally occurring proteins that can switch between multiple, structurally distinct conformations, at least one of which is self-propagating and transmissible to other prions. This transmission of protein state represents an epigenetic phenomenon where information is encoded in the protein structure itself, instead of in nucleic acids. Several prion-forming proteins have been identified in fungi, primarily in the yeast Saccharomyces cerevisiae. These fungal prions are generally considered benign, and in some cases even confer a selectable advantage to the organism.
Fungal prions have provided a model for the understanding of disease-forming mammalian prions. Study of fungal prions has led to a characterisation of the sequence features and mechanisms that enable prion domains to switch between functional and amyloid-forming states.
Sequence features
Prions are formed by portable, transmissible prion domains that are often enriched in asparagine, glutamine, tyrosine and glycine residues. When a reporter protein is fused with a prion domain, it forms a chimeric protein that demonstrates the conformational switching that is characteristic of prions. Meanwhile, removing this prion domain prevents prionogenesis. This suggests that these prion domains are, in fact, portable and are the sole initiator of prionogenesis. This supports the protein-only hypothesis.
A recent study of candidate prion domains in S. cerevisiae found several specific sequence features that were common to proteins showing aggregation and self-templating properties. For example, proteins that aggregated had candidate prion domains that were more highly enriched in asparagine, while non-aggregating domains where more highly enriched in glutamine and charged peptides. There was also evidence that the spacing of charged peptides that prevent amyloid formation, such as proline, is important in prionogenesis. This discovery
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https://en.wikipedia.org/wiki/Dot-matrix%20display
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A dot-matrix display is a low-cost electronic digital display device that displays information on machines such as clocks, watches, calculators, and many other devices requiring a simple alphanumeric (and/or graphic) display device of limited resolution.
The display consists of a dot matrix of lights or mechanical indicators arranged in a rectangular configuration (other shapes are also possible, although not common) such that by switching on or off selected lights, text or graphics can be displayed. These displays are normally created with LCD, OLED, or LED lights and can be found in some Thin Film Transistors. The Thin Film Transistors had an active display which allows the dot matrix to display different pixels with different colors at the same time. A dot matrix controller converts instructions from a processor into signals that turn on or off indicator elements in the matrix so that the required display is produced.
History
The dot-matrix display is also known by the obsolete term "punktmatrix display" (German for point-matrix) due to the dot matrix being created in Germany by Rudolf Hell in 1925.
On September 1977, the US Army wrote up a form to the Westinghouse Research and Development Center requesting a more effective energy source that soldiers could use in their technology in the field. Japan and America were using the LCD matrices to develop Casio TVs from 1984 to 2000 creating and experimenting with different display setups. In the 1980s, dot-matrix displays were introduced into several technologies including computers, the Game Boy, and television screens that were used. The dot matrix displays became a popular public technology in 1991 America when the company Data East created Checkpoint (pinball) machines that interested the public. Dot-matrix displays were added into new pieces of technology as a background part of LCD or OLED displays as the technology improved.
Pixel resolutions
Common sizes of dot matrix displays:
128×16 (Two-lined)
128×3
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https://en.wikipedia.org/wiki/Citrate%20synthase
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The enzyme citrate synthase E.C. 2.3.3.1 (previously 4.1.3.7)] exists in nearly all living cells and stands as a pace-making enzyme in the first step of the citric acid cycle (or Krebs cycle). Citrate synthase is localized within eukaryotic cells in the mitochondrial matrix, but is encoded by nuclear DNA rather than mitochondrial. It is synthesized using cytoplasmic ribosomes, then transported into the mitochondrial matrix.
Citrate synthase is commonly used as a quantitative enzyme marker for the presence of intact mitochondria. Maximal activity of citrate synthase indicates the mitochondrial content of skeletal muscle. The maximal activity can be increased by endurance training or high-intensity interval training, but maximal activity is further increased with high-intensity interval training.
Citrate synthase catalyzes the condensation reaction of the two-carbon acetate residue from acetyl coenzyme A and a molecule of four-carbon oxaloacetate to form the six-carbon citrate:
acetyl-CoA + oxaloacetate + H2O → citrate + CoA-SH
Oxaloacetate is regenerated after the completion of one round of the Krebs cycle.
Oxaloacetate is the first substrate to bind to the enzyme. This induces the enzyme to change its conformation, and creates a binding site for the acetyl-CoA. Only when this citryl-CoA has formed will another conformational change cause thioester hydrolysis and release coenzyme A. This ensures that the energy released from the thioester bond cleavage will drive the condensation.
Structure
Citrate synthase's 437 amino acid residues are organized into two main subunits, each consisting of 20 alpha-helices. These alpha helices compose approximately 75% of citrate synthase's tertiary structure, while the remaining residues mainly compose irregular extensions of the structure, save a single beta-sheet of 13 residues. Between these two subunits, a single cleft exists containing the active site. Two binding sites can be found therein: one reserved for citrat
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https://en.wikipedia.org/wiki/Buffy%20coat
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The buffy coat is the fraction of an anticoagulated blood sample that contains most of the white blood cells and platelets following centrifugation.
Description
After centrifugation, one can distinguish a layer of clear fluid (the plasma), a layer of red fluid containing most of the red blood cells, and a thin layer in between. Composing less than 1% of the total volume of the blood sample, the buffy coat (so-called because it is usually buff in hue), contains most of the white blood cells and platelets. The buffy coat is usually whitish in color, but is sometimes green if the blood sample contains large amounts of neutrophils, which are high in green-colored myeloperoxidase. The layer beneath the buffy coat contains granulocytes and red blood cells.
The buffy coat is commonly used for DNA extraction, with white blood cells providing approximately 10 times more concentrated sources of nucleated cells. They are extracted from the blood of mammals because mammalian red blood cells are anucleate and do not contain DNA. A common protocol is to store buffy coat specimens for future DNA isolation and these may remain in frozen storage for many years.
Diagnostic uses
Quantitative buffy coat (QBC), based on the centrifugal stratification of blood components, is a laboratory test for the detection of malarial parasites, as well as of other blood parasites.
The blood is taken in a QBC capillary tube which is coated with acridine orange (a fluorescent dye) and centrifuged; the fluorescing parasitized erythrocytes get concentrated in a layer which can then be observed by fluorescence microscopy, under ultraviolet light at the interface between red blood cells and buffy coat. This test is more sensitive than the conventional thick smear and in > 90% of cases the species of parasite can also be identified.
In cases of extremely low white blood cell count, it may be difficult to perform a manual differential of the various types of white cells, and it may be virtually impossi
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https://en.wikipedia.org/wiki/Claudia%20Zaslavsky
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Claudia Zaslavsky (January 12, 1917 – January 13, 2006) was an American mathematics teacher and ethnomathematician.
Life
She was born Claudia Natoma Cohen (later changed to Cogan) on January 12, 1917, in Upper Manhattan in New York City and grew up in Allentown, Pennsylvania. She attributed her first interest in mathematics to her early childhood experiences when she helped her parents in their dry goods store.
She studied mathematics at Hunter College and then earned a master's degree in statistics at the University of Michigan.
In the 1950's while raising her children she was the bookkeeper at Chelsea Publishing Co. and taught pre-instrument classes to small children.
Math teacher
She became a mathematics teacher at Woodlands High School in Hartsdale, New York.
She pursued postgraduate study in mathematics education at Teachers College, Columbia University, in 1974–1978.
During that time she sought to learn about mathematics in Africa to better capture the interest of the African-American students in her classes.
She discovered "that little of what was known about this topic [African cultural mathematics] was available in accessible sources." Thus began a years-long project of assembling, organizing and interpreting a vast amount of little-known material on expressions of mathematics in diverse African cultures, including number words and signs, reckoning of time, games, and architectural and decorative patterns. Her field work on a trip to East Africa in 1970 was assisted by the photography of her husband Sam and travel guidance from her son Alan, then teaching in Kenya.
Zaslavsky wrote the book Africa Counts about mathematics in African culture to sum up her discoveries up to that time.
Her work was welcomed into the burgeoning field of ethnomathematics, which studies the ways in which mathematical concepts are expressed and used by people in diverse cultures in the course of everyday life. As she wrote, "scholars of ethnomathematics examine the pr
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https://en.wikipedia.org/wiki/Abhyankar%27s%20conjecture
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In abstract algebra, Abhyankar's conjecture is a conjecture of Shreeram Abhyankar posed in 1957, on the Galois groups of algebraic function fields of characteristic p. The soluble case was solved by Serre in 1990 and the full conjecture was proved in 1994 by work of Michel Raynaud and David Harbater.
Statement
The problem involves a finite group G, a prime number p, and the function field K(C) of a nonsingular integral algebraic curve C defined over an algebraically closed field K of characteristic p.
The question addresses the existence of a Galois extension L of K(C), with G as Galois group, and with specified ramification. From a geometric point of view, L corresponds to another curve , together with
a morphism
π : → C.
Geometrically, the assertion that π is ramified at a finite set S of points on C
means that π restricted to the complement of S in C is an étale morphism.
This is in analogy with the case of Riemann surfaces.
In Abhyankar's conjecture, S is fixed, and the question is what G can be. This is therefore a special type of inverse Galois problem.
Results
The subgroup p(G) is defined to be the subgroup generated by all the Sylow subgroups of G for the prime number p. This is a normal subgroup, and the parameter n is defined as the minimum number of generators of
G/p(G).
Raynaud proved the case where C is the projective line over K, the conjecture states that G can be realised as a Galois group of L, unramified outside S containing s + 1 points, if and only if
n ≤ s.
The general case was proved by Harbater, in which g isthe genus of C and G can be realised if and only if
n ≤ s + 2 g.
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https://en.wikipedia.org/wiki/Modal%20operator
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A modal connective (or modal operator) is a logical connective for modal logic. It is an operator which forms propositions from propositions. In general, a modal operator has the "formal" property of being non-truth-functional in the following sense: The truth-value of composite formulae sometimes depend on factors other than the actual truth-value of their components. In the case of alethic modal logic, a modal operator can be said to be truth-functional in another sense, namely, that of being sensitive only to the distribution of truth-values across possible worlds, actual or not. Finally, a modal operator is "intuitively" characterized by expressing a modal attitude (such as necessity, possibility, belief, or knowledge) about the proposition to which the operator is applied. See also Garson, James, "Modal Logic", The Stanford Encyclopedia of Philosophy (Summer 2021 Edition), Edward N. Zalta (ed.), URL = <https://plato.stanford.edu/archives/sum2021/entries/logic-modal/>
Syntax for modal operators
The syntax rules for modal operators and are very similar to those for universal and existential quantifiers; In fact, any formula with modal operators and , and the usual logical connectives in propositional calculus () can be rewritten to a de dicto normal form, similar to prenex normal form. One major caveat: Whereas the universal and existential quantifiers only binds to the propositional variables or the predicate variables following the quantifiers, since the modal operators and quantifies over accessible possible worlds, they will bind to any formula in their scope. For example, is logically equivalent to , but is not logically equivalent to ; Instead, is logically equivalent to .
When there are both modal operators and quantifiers in a formula, different order of an adjacent pair of modal operator and quantifier can lead to different semantic meanings; Also, when multimodal logic is involved, different order of an adjacent pair of modal operators can al
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https://en.wikipedia.org/wiki/Actigraphy
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Actigraphy is a non-invasive method of monitoring human rest/activity cycles. A small actigraph unit, also called an actimetry sensor, is worn for a week or more to measure gross motor activity. The unit is usually in a wristwatch-like package worn on the wrist. The movements the actigraph unit undergoes are continually recorded and some units also measure light exposure. The data can be later read to a computer and analysed offline; in some brands of sensors the data are transmitted and analysed in real time.
Purpose
Sleep
Sleep actigraphs are generally watch-shaped and worn on the wrist of the non-dominant arm for adults and usually on the ankle for children. They are useful for determining sleep patterns and circadian rhythms and may be worn for several weeks at a time. In the medical setting, traditional polysomnography has long been cited as "the 'gold standard' for sleep assessment." Since the 1990s, however, actigraphy has increasingly been used to assess sleep/wake behavior; especially for young children. Studies have found actigraphy to be helpful for sleep research because it tends to be less expensive and cumbersome than polysomnography. Unlike polysomnography, actigraphy allows the patient to be movable and to continue her or his normal routines while the required data are being recorded in his or her natural sleep environment; this may render the measured data more generally applicable. As sleep actigraphs are more affordable than polysomnographs, their use has advantages, particularly in the case of large field studies.
However, actigraphy cannot be considered as a substitute to polysomnography. A full night sleep measured with polysomnography may be required for some sleep disorders. Indeed, actigraphy may be efficient in measuring sleep parameters and sleep quality, however it is not provided with measures for brain activity (EEG), eye movements (EOG), muscle activity (EMG) or heart rhythm (ECG).
Actigraphy is useful for assessing daytime sle
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https://en.wikipedia.org/wiki/Formal%20derivative
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In mathematics, the formal derivative is an operation on elements of a polynomial ring or a ring of formal power series that mimics the form of the derivative from calculus. Though they appear similar, the algebraic advantage of a formal derivative is that it does not rely on the notion of a limit, which is in general impossible to define for a ring. Many of the properties of the derivative are true of the formal derivative, but some, especially those that make numerical statements, are not.
Formal differentiation is used in algebra to test for multiple roots of a polynomial.
Definition
Fix a ring (not necessarily commutative) and let be the ring of polynomials over .
(If is not commutative, this is the Free algebra over a single indeterminate variable.)
Then the formal derivative is an operation on elements of , where if
then its formal derivative is
In the above definition, for any nonnegative integer and , is defined as usual in a Ring: (with if ).
This definition also works even if does not have a multiplicative identity.
Alternative axiomatic definition
One may also define the formal derivative axiomatically as the map satisfying the following properties.
1) for all
2) The normalization axiom,
3) The map commutes with the addition operation in the polynomial ring,
4) The map satisfies Leibniz's law with respect to the polynomial ring's multiplication operation,
One may prove that this axiomatic definition yields a well-defined map respecting all of the usual ring axioms.
The formula above (i.e. the definition of the formal derivative when the coefficient ring is commutative) is a direct consequence of the aforementioned axioms:
Properties
It can be verified that:
Formal differentiation is linear: for any two polynomials f(x),g(x) in R[x] and elements r,s of R we have
The formal derivative satisfies the Product rule:
Note the order of the factors; when R is not commutative this is important.
These two properties make D a d
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https://en.wikipedia.org/wiki/Escher%20in%20the%20Palace
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Escher in Het Paleis (Escher in The Palace) is a museum in The Hague, Netherlands, featuring the works of the Dutch graphical artist M. C. Escher. It is housed in the Lange Voorhout Palace since November 2002.
In 2015 it was revealed that many of the prints on display at the museum were replicas, scanned from original prints and printed onto the same type of paper used by Escher, rather than original Escher prints as they had been labeled.
History
The museum is housed in the Lange Voorhout Palace, a former royal residence dating back to the eighteenth century. Queen Emma bought the stately house in 1896. She used it as a winter palace from March 1901 until her death in March 1934. It was used by four subsequent Dutch queens for their business offices, until Queen Beatrix moved the office to Paleis Noordeinde. The first and second floors have exhibitions showing the royal period of the palace, highlighting Queen Emma's residence.
The museum features a permanent display of a large number of woodcuts and lithographs by M.C. Escher, among them the world-famous prints, Air and Water (birds become fish); Belvedere (the inside out of a Folly); Waterfall (where water seems to flow upwards); Drawing (two hands drawing each other). Escher in Het Paleis shows the early lovely Italian landscapes, the many mirror prints and a choice from the tesselation drawings, also the three versions of the Metamorphosis, from the first small one, to the third, of 7 meters. This one is shown in a circle. It underlines the new vision of the museum on the work of M.C. Escher.
The third floor of the museum is dedicated to the Optical Illusion, besides the famous Escher Room in which grownups seem to be smaller than their children, one's eyes will be tricked by multiple interactive displays.
Interior
In the rooms of the museum are fifteen chandeliers made by the Rotterdam artist Hans van Bentem. The artist designed these especially for the museum, with some references to the work of Escher
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https://en.wikipedia.org/wiki/Computer%20%28occupation%29
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The term "computer", in use from the early 17th century (the first known written reference dates from 1613), meant "one who computes": a person performing mathematical calculations, before electronic computers became commercially available. Alan Turing described the "human computer" as someone who is "supposed to be following fixed rules; he has no authority to deviate from them in any detail." Teams of people, often women from the late nineteenth century onwards, were used to undertake long and often tedious calculations; the work was divided so that this could be done in parallel. The same calculations were frequently performed independently by separate teams to check the correctness of the results.
Since the end of the 20th century, the term "human computer" has also been applied to individuals with prodigious powers of mental arithmetic, also known as mental calculators.
Origins in sciences
Astronomers in Renaissance times used that term about as often as they called themselves "mathematicians" for their principal work of calculating the positions of planets. They often hired a "computer" to assist them. For some men, such as Johannes Kepler, assisting a scientist in computation was a temporary position until they moved on to greater advancements. Before he died in 1617, John Napier suggested ways by which "the learned, who perchance may have plenty of pupils and computers" might construct an improved logarithm table.
Computing became more organized when the Frenchman Alexis Claude Clairaut (1713–1765) divided the computation to determine the time of the return of Halley's Comet with two colleagues, Joseph Lalande and Nicole-Reine Lepaute. Human computers continued plotting the future movements of astronomical objects to create celestial tables for almanacs in the late 1760s.
The computers working on the Nautical Almanac for the British Admiralty included William Wales, Israel Lyons and Richard Dunthorne. The project was overseen by Nevil Maskelyne. Maskely
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https://en.wikipedia.org/wiki/Pascal%20MicroEngine
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Pascal MicroEngine is a series of microcomputer products manufactured by Western Digital from 1979 through the mid-1980s, designed specifically to run the UCSD p-System efficiently. Compared to other microcomputers, which use a machine language p-code interpreter, the Pascal MicroEngine has its interpreter implemented in microcode; p-code is its machine language. The most common programming language used on the p-System is Pascal.
The MicroEngine runs a special release III p-System. The enhancements of release III were incorporated into release IV which was made publicly available for other platforms but not for the MicroEngine.
Products
The MicroEngine series of products was offered at various levels of integration:
WD-9000 five chip microprocessor chip set
WD-900 single board computer
WD-90 packaged system
SB-1600 MicroEngine single board computer
ME-1600 Modular MicroEngine packaged system
The MicroEngine chipset was based on the MCP-1600 chipset, which formed the basis of the DEC LSI-11 low-end minicomputer and the WD16 processor used by Alpha Microsystems (each using different microcode).
One of the well regarded systems was the S-100 bus based dual processor cards developed by Digicomp Research of Ithaca, NY. These cards deserve an entry on their own, as they survived the demise of the WD single-board system and delivered reliable performance at up to 2.5Mhz. A typical configuration was a Digicomp dual processor board set, containing a Zilog Z80 and a bipolar memory mapper harnessed to a microengine chipset on the second board, linked by a direct cable. The sole configuration known to be still running in 2018 and documented on the web is described by Marcus Wigan and contains 312 kB of memory, RAM disc support through a modified Z80 BIOS (written by Tom Evans) taking advantage of the memory mapping chip on the Z80 board, and using the UCSD Pascal III version of the operating system tuned specifically for the WD chipset - once the Microengine had boo
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https://en.wikipedia.org/wiki/Sabayon%20Linux
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Sabayon Linux or Sabayon (formerly RR4 Linux and RR64 Linux), was an Italian Gentoo-based Linux distribution created by Fabio Erculiani and the Sabayon development team. Sabayon followed the "out of the box" philosophy, aiming to give the user a wide number of applications ready to use and a self-configured operating system.
Sabayon Linux featured a rolling release cycle, its own software repository and a package management system called Entropy. Sabayon was available in both x86 and AMD64 distributions and there was support for ARMv7 in development for the BeagleBone.
It was named after an Italian dessert, zabaione, which is made from eggs. Sabayon's logo was an impression of a chicken foot. In November 2020 it was announced that future Sabayon Linux versions would base on Funtoo instead of Gentoo Linux. Sabayon Linux would hence be rebranded to MocaccinoOS.
Editions
Since version 4.1, Sabayon had been released in two different flavors featuring either the GNOME or KDE desktop environments, with the ultralight Fluxbox environment included as well. (In the previous versions all three environments were included in a DVD ISO image).
Since Sabayon's initial release, additional versions of Sabayon have added other X environments, including Xfce and LXDE. A CoreCD edition which featured a minimal install of Sabayon was released to allow the creation of spins of the Sabayon operating system; however, this was later discontinued and replaced by CoreCDX (fluxbox window manager) and Spinbase (no X environment) first and by "Sabayon Minimal" later. A ServerBase edition was released which featured a server-optimized kernel and a small footprint, but this was later discontinued and integrated into the "Sabayon Minimal".
Daily build images were available to Sabayon testers, but were released weekly to the public on the system mirrors containing stable releases. Official releases were simply DAILY versions which had received deeper testing. The adoption of Molecule led the
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https://en.wikipedia.org/wiki/Comparability
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In mathematics, two elements x and y of a set P are said to be comparable with respect to a binary relation ≤ if at least one of x ≤ y or y ≤ x is true. They are called incomparable if they are not comparable.
Rigorous definition
A binary relation on a set is by definition any subset of Given is written if and only if in which case is said to be to by
An element is said to be , or (), to an element if or
Often, a symbol indicating comparison, such as (or and many others) is used instead of in which case is written in place of which is why the term "comparable" is used.
Comparability with respect to induces a canonical binary relation on ; specifically, the induced by is defined to be the set of all pairs such that is comparable to ; that is, such that at least one of and is true.
Similarly, the on induced by is defined to be the set of all pairs such that is incomparable to that is, such that neither nor is true.
If the symbol is used in place of then comparability with respect to is sometimes denoted by the symbol , and incomparability by the symbol .
Thus, for any two elements and of a partially ordered set, exactly one of and is true.
Example
A totally ordered set is a partially ordered set in which any two elements are comparable. The Szpilrajn extension theorem states that every partial order is contained in a total order. Intuitively, the theorem says that any method of comparing elements that leaves some pairs incomparable can be extended in such a way that every pair becomes comparable.
Properties
Both of the relations and are symmetric, that is is comparable to if and only if is comparable to and likewise for incomparability.
Comparability graphs
The comparability graph of a partially ordered set has as vertices the elements of and has as edges precisely those pairs of elements for which .
Classification
When classifying mathematical objects (e.g., topological spaces), two are sa
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https://en.wikipedia.org/wiki/WS-Discovery
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Web Services Dynamic Discovery (WS-Discovery) is a technical specification that defines a multicast discovery protocol to locate services on a local network. It operates over TCP and UDP port 3702 and uses IP multicast address or . As the name suggests, the actual communication between nodes is done using web services standards, notably SOAP-over-UDP.
Various components in Microsoft's Windows Vista operating system use WS-Discovery, e.g. "People near me". The component WSDMON in Windows 7 and later uses WS-Discovery to automatically discover WSD-enabled network printers, which show in Network in Windows Explorer, and can be installed by double-clicking on them. In Windows 8 or later installation is automatic. WS-Discovery is enabled by default in networked HP printers since 2008. WS-Discovery is an integral part of Windows Rally technologies and Devices Profile for Web Services.
The protocol was originally developed by BEA Systems, Canon, Intel, Microsoft, and WebMethods. On July 1, 2009 it was approved as a standard by OASIS.
See also
Avahi
Bonjour
DHCP
Jini
List of Web service specifications
LLMNR
OSGi Alliance
SSDP
Universal Plug and Play (UPnP)
Web Services Discovery
Web Services for Devices
Zero-configuration networking (Zeroconf)
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https://en.wikipedia.org/wiki/Supertoys%20Last%20All%20Summer%20Long
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"Supertoys Last All Summer Long" is a science fiction short story by Brian Aldiss, first published in the UK edition of Harper's Bazaar, in its December 1969 issue. The story deals with humanity in an age of intelligent machines and of the aching loneliness endemic in an overpopulated future where child creation is controlled.
In the same year, the short story was republished in the eponymous Aldiss short-story collection Supertoys Last All Summer Long and Other Stories of Future Time, along with the tie-in stories Supertoys When Winter Comes and Supertoys in Other Seasons. The collection also contained a number of stories not tied to the Supertoys theme. The short story was later used as the basis for the first act of the feature film A.I. Artificial Intelligence directed by Steven Spielberg in 2001.
Plot
In a dystopian future where only a quarter of the world's oversized human population is fed and living comfortably, families must request permission to bear children. Monica Swinton lives with her husband, Henry, and her young son, David, with whom she struggles to bond. She seeks help from Teddy, a robot toy companion of sorts, to try to understand why she feels unable to communicate with David, let alone feel compassion for him. David also questions Teddy about whether his mother truly loves him and wonders whether he is truly real. He attempts to write letters of his own to explain how he feels about his mother and the inner conflict he faces but all of his letters remain unfinished.
Meanwhile, the story jumps to Henry, who is in a meeting with a company he is associated with known as Synthank. They are discussing artificial life forms and bio-electronic beings for future developments. Henry tells them he believes that the new AI under production will finally solve humanity's problems with experiencing personal isolation and loneliness.
Monica discovers David's unfinished letters which express both love and a jealous contempt for Teddy, whom Monica always
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https://en.wikipedia.org/wiki/Nursing%20pin
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A nursing pin is a type of badge, usually made of metal such as gold or silver, which is worn by nurses to identify the nursing school from which they graduated. They are traditionally presented to the newly graduated nurses by the faculty at a pinning ceremony as a symbolic welcome into the profession. Most pins have a symbolic meaning, often representing the history of the nursing program for that school of nursing.
The ancestor of the nursing pin is the Maltese cross. Some significant historical contributors to the foundation of hospital standards involved in using the Maltese cross were the Knights Hospitaller and Order of Saint Lazarus, pioneers of communicable disease care, such as leprosy, syphilis, and other chronic skin diseases during their period, and established one of a few hospitals in the territories of their reign. As the Renaissance period progressed, the use of the symbol has evolved into family coat of arms, then given to those who were providers of exclusive services. Such pins were then awarded to nurses who were needed by society during periods of spread of uncontrolled illnesses during the early period, and to recognize them as nurses who are educated, trained and experienced in the said field.
Nurse's pins today
Modern designs of nurses' pins have evolved through time. The Maltese cross, in some nursing educational institutions, has not been incorporated in their pins. Instead, their own seal or logo, such as that of their nursing school, nursing organization or university affiliation is used. The pin is still worn as part of nurses' uniforms today, in such cases, before or even after they graduate from their respective nursing schools and work for medical institutions, such as hospitals and health and wellness centers.
Nursing symbols
Pins vary widely in shape and imagery, generally about the proportions of a woman's brooch (less than 10 cm diameter). A common graphic is an old pattern oil lamp. These lamps or candles were the only light
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https://en.wikipedia.org/wiki/Extraterrestrial%20%28TV%20program%29
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Extraterrestrial (also Alien Worlds in the UK) is a British-American two-part television documentary miniseries, aired in 2005 in the UK by Channel 4, by the National Geographic Channel (as Extraterrestrial) in the US on Monday, May 30, 2005 and produced by Big Wave Productions Ltd. The program focuses on the hypothetical and scientifically feasible evolution of alien life on extrasolar planets, providing model examples of two different fictional worlds, one in each of the series's two episodes.
The documentary is based on speculative collaboration of a group of American and British scientists, who were collectively commissioned by National Geographic. For the purposes of the documentary, the team of scientists divides two hypothetical examples of realistic worlds on which extraterrestrial life could evolve: A tidally locked planet (dubbed "Aurelia") orbiting a red dwarf star and a large moon (dubbed "Blue Moon") orbiting a gas giant in a binary star system. The scientific team of the series used a combination of accretion theory, climatology, and xenobiology to imagine the most likely locations for extraterrestrial life and most probable evolutionary path such life would take.
The "Aurelia" and "Blue Moon" concepts seen in the series were also featured in the touring exhibition The Science of Aliens.
Series concept and scientific basis
At the start of the documentary, the presenter and team of scientists draw attention to their reasons for speculating about life on extrasolar planets. Discoveries regarding extrasolar planets were first published in 1989 raising the prospect of whether life (as we know it or imagine it) could be supported on other planets. It is currently believed that for this to happen a planet must orbit in a relatively narrow band around its parent star, where temperatures are suitable for water to exist as a liquid. This region is called the habitable zone.
The most Earth-like exoplanets yet found, Gliese 667 Cc and Gliese 581g (disputed)
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https://en.wikipedia.org/wiki/OpenVAS
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OpenVAS (Open Vulnerability Assessment Scanner, originally known as GNessUs) is the scanner component of Greenbone Vulnerability Management (GVM), a software framework of several services and tools offering vulnerability scanning and vulnerability management.
All Greenbone Vulnerability Management products are free software, and most components are licensed under the GNU General Public License (GPL). Plugins for Greenbone Vulnerability Management are written in the Nessus Attack Scripting Language, NASL.
History
Greenbone Vulnerability Manager began under the name of OpenVAS, and before that the name GNessUs, as a fork of the previously open source Nessus scanning tool, after its developers Tenable Network Security changed it to a proprietary (closed source) license in October 2005. OpenVAS was originally proposed by pentesters at SecuritySpace, discussed with pentesters at Portcullis Computer Security and then announced by Tim Brown on Slashdot.
Greenbone Vulnerability Manager is a member project of Software in the Public Interest.
Structure
There is a daily updated feed of Network Vulnerability Tests (NVTs). , there were over 50,000 NVTs.
Documentation
The OpenVAS protocol structure aims to be well-documented to assist developers. The OpenVAS Compendium is a publication of the OpenVAS Project that delivers documentation on OpenVAS.
See also
Aircrack-ng
BackBox
BackTrack
Kali Linux
Kismet (software)
List of free and open-source software packages
Metasploit Project
Nmap
ZMap (software)
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https://en.wikipedia.org/wiki/Logical%20Disk%20Manager
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The Logical Disk Manager (LDM) is an implementation of a logical volume manager for Microsoft Windows NT, developed by Microsoft and Veritas Software. It was introduced with the Windows 2000 operating system, and is supported in Windows XP, Windows Server 2003, Windows Vista, Windows 7, Windows 8, Windows 10 and Windows 11. The MMC-based Disk Management snap-in () hosts the Logical Disk Manager. On Windows 8 and Windows Server 2012, Microsoft deprecated LDM in favor of Storage Spaces.
Logical Disk Manager enables disk volumes to be dynamic, in contrast to the standard basic volume format. Basic volumes and dynamic volumes differ in their ability to extend storage beyond one physical disk. Basic partitions are restricted to a fixed size on one physical disk. Dynamic volumes can be enlarged to include more free space - either from the same disk or another physical disk. (For more information on the difference, see Basic and dynamic disks and volumes, below.)
Overview
Basic storage involves dividing a disk into primary and extended partitions. This is the route that all versions of Windows that were reliant on DOS-handled storage took, and disks formatted in this manner are known as basic disks. Dynamic storage involves the use of a single partition that covers the entire disk, and the disk itself is divided into volumes or combined with other disks to form volumes that are greater in size than one disk itself. Volumes can use any supported file system.
Basic disks can be upgraded to dynamic disks; however, when this is done the disk cannot easily be downgraded to a basic disk again. To perform a downgrade, data on the dynamic disk must first be backed up onto some other storage device. Second, the dynamic disk must be re-formatted as a basic disk (erasing all data). Finally, data from the backup must be copied back over to the newly re-formatted basic disk.
Dynamic disks provide the capability for software implementations of RAID. The main disadvantage of dynami
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https://en.wikipedia.org/wiki/CANopen
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CANopen is a communication protocol and device profile specification for embedded systems used in automation. In terms of the OSI model, CANopen implements the layers above and including the network layer. The CANopen standard consists of an addressing scheme, several small communication protocols and an application layer defined by a device profile. The communication protocols have support for network management, device monitoring and communication between nodes, including a simple transport layer for message segmentation/desegmentation. The lower level protocol implementing the data link and physical layers is usually Controller Area Network (CAN), although devices using some other means of communication (such as Ethernet Powerlink, EtherCAT) can also implement the CANopen device profile.
The basic CANopen device and communication profiles are given in the CiA 301 specification released by CAN in Automation. Profiles for more specialized devices are built on top of this basic profile, and are specified in numerous other standards released by CAN in Automation, such as CiA 401 for I/O-modules and CiA 402 for motion control.
Device model
Every CANopen device has to implement certain standard features in its controlling software.
A communication unit implements the protocols for messaging with the other nodes in the network.
Starting and resetting the device is controlled via a state machine. It must contain the states Initialization, Pre-operational, Operational and Stopped. The transitions between states are made by issuing a network management (NMT) communication object to the device.
The object dictionary is an array of variables with a 16-bit index. Additionally, each variable can have an 8-bit subindex. The variables can be used to configure the device and reflect its environment, i.e. contain measurement data.
The application part of the device actually performs the desired function of the device, after the state machine is set to the operational state
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https://en.wikipedia.org/wiki/Off-key
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Off-key is musical content that is not at the expected frequency or pitch period, either with respect to some absolute reference frequency, or in a ratiometric sense (i.e. through removal of exactly one degree of freedom, such as the frequency of a keynote), or pitch intervals not well-defined in the ratio of small whole numbers.
The term may also refer to a person or situation being out of step with what is considered normal or appropriate. A single note deliberately played or sung off-key can be called an "off-note". It is sometimes used the same way as a blue note in jazz.
Explanation of on-key
The opposite of off-key is on-key or in-key, which suggests that there is a well defined keynote, or reference pitch. This does not necessarily have to be an absolute pitch but rather one that is relative for at least the duration of a song. A song is usually in a certain key, which is usually the note that the song ends on, and is the base frequency around which it resolves to at the end.
The base-frequency is usually called the harmonic or key center. Being on-key presumes that there is a key center frequency around which some portion of notes have well defined intervals to.
Deliberate use off-key content
In jazz and blues music, certain notes called "blue notes" are deliberately sung somewhat flat for expressive effect. Examples include the words "Thought He Was a Goner" in the song "And the Cat Came Back" and the words "Yum Yum" in the children's song "Five Green and Speckled Frogs".
See also
Melody
Tonality
Blue note
Tonic (music)
Notes
Musical tuning
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https://en.wikipedia.org/wiki/Trilinear%20coordinates
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In geometry, the trilinear coordinates of a point relative to a given triangle describe the relative directed distances from the three sidelines of the triangle. Trilinear coordinates are an example of homogeneous coordinates. The ratio is the ratio of the perpendicular distances from the point to the sides (extended if necessary) opposite vertices and respectively; the ratio is the ratio of the perpendicular distances from the point to the sidelines opposite vertices and respectively; and likewise for and vertices and .
In the diagram at right, the trilinear coordinates of the indicated interior point are the actual distances (, , ), or equivalently in ratio form, for any positive constant . If a point is on a sideline of the reference triangle, its corresponding trilinear coordinate is 0. If an exterior point is on the opposite side of a sideline from the interior of the triangle, its trilinear coordinate associated with that sideline is negative. It is impossible for all three trilinear coordinates to be non-positive.
Notation
The ratio notation for trilinear coordinates is often used in preference to the ordered triple notation with the latter reserved for triples of directed distances relative to a specific triangle. The trilinear coordinates can be rescaled by any arbitrary value without affecting their ratio. The bracketed, comma-separated triple notation can cause confusion because conventionally this represents a different triple than e.g. but these equivalent ratios represent the same point.
Examples
The trilinear coordinates of the incenter of a triangle are ; that is, the (directed) distances from the incenter to the sidelines are proportional to the actual distances denoted by , where is the inradius of . Given side lengths we have:
Note that, in general, the incenter is not the same as the centroid; the centroid has barycentric coordinates (these being proportional to actual signed areas of the triangles , where = centroi
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https://en.wikipedia.org/wiki/Lewis%20Goldberg
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Lewis R. Goldberg is an American personality psychologist and a professor emeritus at the University of Oregon. He is closely associated
with the lexical hypothesis that any culturally important personality characteristic will be represented in the language of that culture. This hypothesis led to a five factor structure of personality trait adjectives (which he dubbed the Big 5). When applied to personality items this structure is also known as the five-factor model (FFM) of personality. He is the creator of the International Personality Item Pool(IPIP), a website that provides public-domain personality measures.
Education
Lew Goldberg was born in Chicago, Illinois, on January 28, 1932. His early education took place at the Bret Harte elementary school in Chicago, and the Highland Park High School in Highland Park, Illinois. In 1953 Goldberg received an A.B. in social relations from Harvard University. He earned a Ph.D. in psychology from the University of Michigan in 1958 where his Ph.D. advisor was E. Lowell Kelly; Kelly provided Goldberg with training in the methodology of quantitative personality assessment.
Academic career
As an advanced graduate student at Michigan, Goldberg met Warren T. Norman, a new assistant professor, who became a lifelong friend and collaborator on issues in personality structure and assessment. Their initial work together on the generality of the Big 5, and their subsequent work on the lexical hypothesis has had a major impact upon the development of a consensual model of personality. After receiving his doctorate, Goldberg became a visiting assistant professor at Stanford University. Since 1960 he has taught at the University of Oregon, where he is professor emeritus. He is a senior scientist at the Oregon Research Institute, where he has carried out research since 1961.
From 1962 to 1966, Goldberg served as a field selection officer for the United States Peace Corps. In 1966 he became a Fulbright professor at the Univers
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https://en.wikipedia.org/wiki/Seismic%20anisotropy
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Seismic anisotropy is the directional dependence of the velocity of seismic waves in a medium (rock) within the Earth.
Description
A material is said to be anisotropic if the value of one or more of its properties varies with direction. Anisotropy differs from the property called heterogeneity in that anisotropy is the variation in values with direction at a point while heterogeneity is the variation in values between two or more points.
Seismic anisotropy can be defined as the dependence of seismic velocity on direction or upon angle. General anisotropy is described by a 4th order elasticity tensor with 21 independent elements. However, in practice observational studies are unable to distinguish all 21 elements, and anisotropy is usually simplified. In the simplest form, there are two main types of anisotropy, both of them are called transverse isotropy (it is called transverse isotropy because there is isotropy in either the horizontal or vertical plane) or polar anisotropy. The difference between them is in their axis of symmetry, which is an axis of rotational invariance such that if we rotate the formation about the axis, the material is still indistinguishable from what it was before. The symmetry axis is usually associated with regional stress or gravity.
VTI- transverse isotropy with a vertical axis of symmetry, this is also called VTI (vertical transverse isotropy). This kind of anisotropy is associated with layering and shale and is found where gravity is the dominant factor.
HTI- transverse isotropy with a horizontal axis of symmetry, this is also called HTI (horizontal transverse isotropy). This kind of anisotropy is associated with cracks and fractures and is found where regional stress is the dominant factor.
The transverse anisotropic matrix has the same form as the isotropic matrix, except that it has five non-zero values distributed among 12 non-zero elements.
Transverse isotropy is sometimes called transverse anisotropy or anisotropy with hex
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https://en.wikipedia.org/wiki/Metasploit
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The Metasploit Project is a computer security project that provides information about security vulnerabilities and aids in penetration testing and IDS signature development. It is owned by Boston, Massachusetts-based security company Rapid7.
Its best-known sub-project is the open-source Metasploit Framework, a tool for developing and executing exploit code against a remote target machine. Other important sub-projects include the Opcode Database, shellcode archive and related research.
The Metasploit Project includes anti-forensic and evasion tools, some of which are built into the Metasploit Framework. Metasploit is pre-installed in the Kali Linux operating system.
History
Metasploit was created by H. D. Moore in 2003 as a portable network tool using Perl. By 2007, the Metasploit Framework had been completely rewritten in Ruby. On October 21, 2009, the Metasploit Project announced that it had been acquired by Rapid7, a security company that provides unified vulnerability management solutions.
Like comparable commercial products such as Immunity's Canvas or Core Security Technologies' Core Impact, Metasploit can be used to test the vulnerability of computer systems or to break into remote systems. Like many information security tools, Metasploit can be used for both legitimate and unauthorized activities. Since the acquisition of the Metasploit Framework, Rapid7 has added an open core proprietary edition called Metasploit Pro.
Metasploit's emerging position as the de facto exploit development framework led to the release of software vulnerability advisories often accompanied by a third party Metasploit exploit module that highlights the exploitability, risk and remediation of that particular bug. Metasploit 3.0 began to include fuzzing tools, used to discover software vulnerabilities, rather than just exploits for known bugs. This avenue can be seen with the integration of the lorcon wireless (802.11) toolset into Metasploit 3.0 in November 2006.
Framework
Th
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https://en.wikipedia.org/wiki/Vulval%20vestibule
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The vulval vestibule (also known as the vulvar vestibule or vestibule of vagina) is the part of the vulva between the labia minora. On the inside, the urinary meatus and the vaginal opening open to the vestibule, while the outer edge is marked by Hart's line, named after David Berry Hart.
It represents the distal end of the urogenital sinus of the embryo.
Structure
Structures opening in the vulval vestibule are the urethra, vagina, Bartholin's glands, and Skene's ducts.
The external urethral orifice is placed about 25–30 millimetres (1–1.2 in) behind the clitoris and immediately in front of that of the vagina; it usually assumes the form of a short, sagittal cleft with slightly raised margins. Nearby are the openings of the Skene's ducts.
The vaginal orifice is a median slit below and behind the opening of the urethra; its size varies inversely with that of the hymen.
To the left and right of the vulval vestibule are the labia minora. Anterior to it are the clitoral hood, frenulum clitoridis, and the clitoral glans. Posterior to it is the posterior commissure of the labia minora and the frenulum of labia minora.
The sides of the vestibule are visible as Hart's line on the inside of the inner lips. Hart's line is the outer edge of the area and marks the change from vulvar skin to the smoother transitional skin of the vulva.
Clinical significance
The prevalence of pain at the vulvar vestibule is relatively common. A study by the University of Michigan found that about 28% of women have experienced vulvar vestibular pain in the past, and about 8% had the pain in the last 6 months.
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https://en.wikipedia.org/wiki/Cox%20Models
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Cox Models, a former division of Estes Industries of Penrose, Colorado, was a multimillion-dollar hobby company, is one of the hobby industry's oldest companies and is noted for its production of miniature model internal-combustion engines.
History
The company, originally named The L. M. Cox Manufacturing Co, Inc., was founded in 1945 by the machinist Roy Cox in Placentia, California. Cox grew up in and around his father's bicycle shop, and he developed an interest in mechanical devices. Cox's first products were wooden pop guns, produced in his home garage. Cox chose wood for his basic material, since metal was scarce during WW II.
When metals became readily available in the United States in 1947, Cox turned his attention to new products, beginning with a diecast metal car. This product was developed into a "whip car", a tethered vehicle which could be manually swung in a circle at high speed. Nitro- and gasoline-powered tether cars with .60 cubic inch miniature engines capable of speeds of 100 mph (160 km/h) were quickly becoming popular. Cox's first contribution to that growing hobby was a cast aluminum midget racer powered by a .15 engine by Cameron Brothers.
Cox Manufacturing enjoyed a large postwar growth due in part to its production of miniature model internal combustion engines and control line model aircraft, finally moving to a new factory in Santa Ana, California, in 1963. The factory started at 80,000 square feet (7432 square meters). Three expansions in a few years' time saw expansion to 225,000 square feet (20,903 square meters) and introduction of a line of slot cars, model rockets, HO scale model trains, and a full-sized, one-horsepower gasoline-powered chain saw.
Roy Cox retired in 1969, and he sold the company to the hobby conglomerate "Leisure Dynamics". Kites, toy walkie-talkies, and yo-yos were added to the Cox company products. A major step toward participation in the growing radio controlled hobby business happened in 1976 with the
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https://en.wikipedia.org/wiki/Solaris%20IP%20network%20multipathing
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The IP network multipathing or IPMP is a facility provided by Solaris to provide fault-tolerance and load spreading for network interface cards (NICs). With IPMP, two or more NICs are dedicated for each network to which the host connects. Each interface can be assigned a static "test" IP address, which is used to assess the operational state of the interface. Each virtual IP address is assigned to an interface, though there may be more interfaces than virtual IP addresses, some of the interfaces being purely for standby purposes. When the failure of an interface is detected its virtual IP addresses are swapped to an operational interface in the group.
The IPMP load spreading feature increases the machine's bandwidth by spreading the outbound load between all the cards in the same IPMP group.
in.mpathd is the daemon in the Solaris OS responsible for IPMP functionality.
See also
Multihoming
Multipath routing
Multipath TCP
Common Address Redundancy Protocol
External links
Enterprise Networking Article, February 2, 2006
Introducing IPMP - Oracle Solaris 11
IPMP section from Sun Solaris 10 System Administration Guide
Networking standards
Sun Microsystems software
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https://en.wikipedia.org/wiki/ADM%20formalism
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The ADM formalism (named for its authors Richard Arnowitt, Stanley Deser and Charles W. Misner) is a Hamiltonian formulation of general relativity that plays an important role in canonical quantum gravity and numerical relativity. It was first published in 1959.
The comprehensive review of the formalism that the authors published in 1962 has been reprinted in the journal General Relativity and Gravitation, while the original papers can be found in the archives of Physical Review.
Overview
The formalism supposes that spacetime is foliated into a family of spacelike surfaces , labeled by their time coordinate , and with coordinates on each slice given by . The dynamic variables of this theory are taken to be the metric tensor of three-dimensional spatial slices and their conjugate momenta . Using these variables it is possible to define a Hamiltonian, and thereby write the equations of motion for general relativity in the form of Hamilton's equations.
In addition to the twelve variables and , there are four Lagrange multipliers: the lapse function, , and components of shift vector field, . These describe how each of the "leaves" of the foliation of spacetime are welded together. The equations of motion for these variables can be freely specified; this freedom corresponds to the freedom to specify how to lay out the coordinate system in space and time.
Notation
Most references adopt notation in which four dimensional tensors are written in abstract index notation, and that Greek indices are spacetime indices taking values (0, 1, 2, 3) and Latin indices are spatial indices taking values (1, 2, 3). In the derivation here, a superscript (4) is prepended to quantities that typically have both a three-dimensional and a four-dimensional version, such as the metric tensor for three-dimensional slices and the metric tensor for the full four-dimensional spacetime .
The text here uses Einstein notation in which summation over repeated indices is assumed.
Two types
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https://en.wikipedia.org/wiki/Ian%20Frazer
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Ian Hector Frazer (born 6 January 1953) is a Scottish-born Australian immunologist, the founding CEO and Director of Research of the Translational Research Institute (Australia). Frazer and Jian Zhou developed and patented the basic technology behind the HPV vaccine against cervical cancer at the University of Queensland. Researchers at the National Cancer Institute, Georgetown University, and University of Rochester also contributed to the further development of the cervical cancer vaccine in parallel.
Education
Frazer was born in Glasgow, Scotland. His parents were medical scientists, and he was drawn to science from a young age.
Frazer attended Aberdeen private school Robert Gordon's College. He chose to pursue medicine over an earlier interest in physics due to physics having fewer research opportunities, and he received his Bachelor of Science and Bachelor of Medicine and Bachelor of Surgery, at the University of Edinburgh in 1974 and 1977 respectively. It was during this time that he met his wife Caroline, whom he married in 1976. His 1978–79 residency was in the Edinburgh Eastern General Hospital, the Edinburgh Royal Infirmary and the Roodlands General Hospital in Haddington.
In 1980/81 Frazer immigrated to Melbourne after he was headhunted by Dr. Ian Mackay at the Walter and Eliza Hall Institute of Medical Research to research viral immunology. In 1981 he discovered that the immunodeficiency afflicting homosexuals in San Francisco was also found in the gay men in his hepatitis B study, and in 1984 helped to confirm that HIV was a cause. It was also found that another sexually transmitted virus was having a surprising effect: the human papilloma virus (HPV) infection seemed to be inducing precancerous cells.
In 1985 he moved to the University of Queensland as a Senior Lecturer, with the opportunity to establish his own research laboratory. It was here in the Lions Human Immunology Laboratories he continued to research HPV in men, and contributed to HIV
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https://en.wikipedia.org/wiki/Bismuth%20telluride
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Bismuth telluride () is a gray powder that is a compound of bismuth and tellurium also known as bismuth(III) telluride. It is a semiconductor, which, when alloyed with antimony or selenium, is an efficient thermoelectric material for refrigeration or portable power generation. is a topological insulator, and thus exhibits thickness-dependent physical properties.
Properties as a thermoelectric material
Bismuth telluride is a narrow-gap layered semiconductor with a trigonal unit cell. The valence and conduction band structure can be described as a many-ellipsoidal model with 6 constant-energy ellipsoids that are centered on the reflection planes. cleaves easily along the trigonal axis due to Van der Waals bonding between neighboring tellurium atoms. Due to this, bismuth-telluride-based materials used for power generation or cooling applications must be polycrystalline. Furthermore, the Seebeck coefficient of bulk becomes compensated around room temperature, forcing the materials used in power-generation devices to be an alloy of bismuth, antimony, tellurium, and selenium.
Recently, researchers have attempted to improve the efficiency of -based materials by creating structures where one or more dimensions are reduced, such as nanowires or thin films. In one such instance n-type bismuth telluride was shown to have an improved Seebeck coefficient (voltage per unit temperature difference) of −287 μV/K at 54 °C, However, one must realize that Seebeck coefficient and electrical conductivity have a tradeoff: a higher Seebeck coefficient results in decreased carrier concentration and decreased electrical conductivity.
In another case, researchers report that bismuth telluride has high electrical conductivity of 1.1×105 S·m/m2 with its very low lattice thermal conductivity of 1.20 W/(m·K), similar to ordinary glass.
Properties as a topological insulator
Bismuth telluride is a well-studied topological insulator. Its physical properties have been shown to change at highly
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https://en.wikipedia.org/wiki/Fermentek
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Fermentek Ltd. is a biotechnological company in the Atarot industrial zone of Jerusalem, Israel. It specializes in the research, development and manufacture of biologically active, natural products isolated from microorganisms as well as from other natural sources such as plants and algae.
The main microorganisms used are nonpathogenic actinomycetes, Nocardia and Streptomycetes. The fungi used are: Penicillium, Aspergillus, Fusarium and the like. None of these is a human pathogen.
Fermentek does not sell to individuals. Most of its products are marketed through major international distributors specializing in chemicals, under their own brand names. Nevertheless, Fermentek has specific impact on the biochemical market, especially in the field of mycotoxins.
Mycotoxins are toxic compounds produced by molds in human food and farm animal feeds, thus being economically important factors. Fermentek manufactures an extensive line of pure mycotoxins used as standards in food analysis. In some cases, such as Aflatoxin M2, Fermentek supplies the entire world's requirements.
In 2009, Fermentek announced a product family of highly standardized calibrant solutions of main mycotoxins. These are marketed under the brand name FermaSol. In 2010, it obtained ISO 13485 accreditation in connection with the production of starting materials for experimental drug production, and with manufacturing of reference standards of food contaminants.
None of Fermentek's products have been invented by it. Fermentek's aim is to make known compounds affordable to the scientific community.
Fermentek was founded by Dr. Yosef Behrend in 1994. It moved in 2004 to its new building, quadrupling its working space and greatly enlarging its manufacturing capacities.
Technology
Fermentek operates fermentors ranging in size from 10 to 15,000 liters, with filter presses and centrifuges of matching capacity.
According to the company policy as declared at its official website, Fermentek uses only the "Cla
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https://en.wikipedia.org/wiki/Superior%20cerebellar%20artery
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The superior cerebellar artery (SCA) is an artery of the head. It arises near the end of the basilar artery. It is a branch of the basilar artery. It supplies parts of the cerebellum, the midbrain, and other nearby structures. It is the cause of trigeminal neuralgia in some patients.
Structure
The superior cerebellar artery arises near the end of the basilar artery. It passes laterally around the brainstem. This is immediately below the oculomotor nerve, which separates it from the posterior cerebral artery. It then winds around the cerebral peduncle, close to the trochlear nerve. It also lies close to the cerebellar tentorium. When it arrives at the upper surface of the cerebellum, it divides into branches which ramify in the pia mater and anastomose with those of the anterior inferior cerebellar arteries and the posterior inferior cerebellar arteries.
Several branches are given to the pineal body, the anterior medullary velum, and the tela chorioidea of the third ventricle.
Function
The superior cerebellar artery supplies deep parts and superior parts of the cerebellum. It supplies parts of the midbrain (tectum, including the cerebral crus). It also supplies superior medullary velum, the superior cerebellar peduncle, the middle cerebellar peduncle, and the interpeduncular region.
Clinical significance
Trigeminal neuralgia
The superior cerebellar artery is frequently the cause of trigeminal neuralgia. It compresses the trigeminal nerve (CN V), causing pain on the patient's face (the distribution of the nerve). This may be treated with vascular microsurgery to decompress the trigeminal nerve. At autopsy, 50% of people without trigeminal neuralgia will also be noted to have vascular compression of the nerve.
Stroke
An infarction of the superior cerebellar artery can cause a cerebellar stroke. This can cause a headache and ataxia (with problems walking).
See also
Posterior cerebral artery
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