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https://en.wikipedia.org/wiki/The%20Hacker%20and%20the%20Ants
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The Hacker and the Ants is a science fiction novel by American writer and mathematician Rudy Rucker, published in 1994 by Avon Books. It was written while Rucker was working as a programmer at Autodesk, Inc., of Sausalito, California from 1988 to 1992.
Plot summary
Jerzy Rugby is trying to create truly intelligent robots. While his actual life crumbles, Rugby toils in his virtual office, testing the robots online. Then, something goes wrong and zillions of computer virus ants invade the net. Rugby is the man wanted for the crime. He's been set up to take a fall for a giant cyberconspiracy and he needs to figure out who — or what — is sabotaging the system in order to clear his name. Plunging deep into the virtual worlds of Antland of Fnoor to find some answers, Rugby confronts both electronic and all-too-real perils, facing death itself in a battle for his freedom.
Transrealism
The main character is a transrealist interpretation of Rucker's life in the 1970s. (Rucker taught mathematics at the State University College at Geneseo, New York from 1972 to 1978.) As such, though the character is fictional, he bears some exaggerated resemblance to Rucker's interpretation of himself at the time. Rucker tells John Shirley in the introduction to recent editions, "I have never really left my body and gone to infinity's Heaven."
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https://en.wikipedia.org/wiki/LastPass
|
LastPass is a password manager application owned by GoTo (formerly LogMeIn Inc.). The standard version of LastPass comes with a web interface, but also includes plugins for various web browsers and apps for many smartphones. It also includes support for bookmarklets.
LastPass suffered significant security incidents between 2011 and 2022. Notably, in late 2022, user data, billing information, and vaults (with some fields encrypted and others not) were breached, leading many security professionals to call for users to change all their passwords and switch to other password managers.
Overview
A user's content in LastPass, including passwords and secure notes, is protected by one master password. The content is synchronized to any device the user uses the LastPass software or app extensions on. Information is encrypted with AES-256 encryption with PBKDF2 SHA-256, salted hashes, and the ability to increase password iterations value. Encryption and decryption takes place at the device level.
LastPass has a form filler that automates password entering and form filling, and it supports password generation, site sharing and site logging, and two-factor authentication. LastPass supports two-factor authentication via various methods including the LastPass Authenticator app for mobile phones as well as others including YubiKey. LastPass is available as an extension to many web browsers, including Google Chrome, Mozilla Firefox, Apple Safari, Microsoft Edge, Vivaldi, and Opera. It also has apps available for smartphones running the Android, iOS, or Windows Phone operating systems. The apps have offline functionality.
Unlike some other major password managers, LastPass offers a user-set password hint, allowing access when the master password is missing.
History
On December 2, 2010, it was announced that LastPass had acquired Xmarks, a web browser extension that enabled password synchronization between browsers. The acquisition meant the survival of Xmarks, which had finan
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https://en.wikipedia.org/wiki/Schema%20migration
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In software engineering, a schema migration (also database migration, database change management) refers to the management of version-controlled, incremental and reversible changes to relational database schemas. A schema migration is performed on a database whenever it is necessary to update or revert that database's schema to some newer or older version.
Migrations are performed programmatically by using a schema migration tool. When invoked with a specified desired schema version, the tool automates the successive application or reversal of an appropriate sequence of schema changes until it is brought to the desired state.
Most schema migration tools aim to minimize the impact of schema changes on any existing data in the database. Despite this, preservation of data in general is not guaranteed because schema changes such as the deletion of a database column can destroy data (i.e. all values stored under that column for all rows in that table are deleted). Instead, the tools help to preserve the meaning of the data or to reorganize existing data to meet new requirements. Since meaning of the data often cannot be encoded, the configuration of the tools usually needs manual intervention.
Risks and benefits
Schema migration allows for fixing mistakes and adapting the data as requirements change. They are an essential part of software evolution, especially in agile environments (see below).
Applying a schema migration to a production database is always a risk. Development and test databases tend to be smaller and cleaner. The data in them is better understood or, if everything else fails, the amount of data is small enough for a human to process. Production databases are usually huge, old and full of surprises. The surprises can come from many sources:
Corrupt data that was written by old versions of the software and not cleaned properly
Implied dependencies in the data which no one knows about anymore
People directly changing the database without using the
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https://en.wikipedia.org/wiki/Comment%20%28computer%20programming%29
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In computer programming, a comment is a programmer-readable explanation or annotation in the source code of a computer program. They are added with the purpose of making the source code easier for humans to understand, and are generally ignored by compilers and interpreters. The syntax of comments in various programming languages varies considerably.
Comments are sometimes also processed in various ways to generate documentation external to the source code itself by documentation generators, or used for integration with source code management systems and other kinds of external programming tools.
The flexibility provided by comments allows for a wide degree of variability, but formal conventions for their use are commonly part of programming style guides.
Overview
Comments are generally formatted as either block comments (also called prologue comments or stream comments) or line comments (also called inline comments).
Block comments delimit a region of source code which may span multiple lines or a part of a single line. This region is specified with a start delimiter and an end delimiter. Some programming languages (such as MATLAB) allow block comments to be recursively nested inside one another, but others (such as Java) do not.
Line comments either start with a comment delimiter and continue until the end of the line, or in some cases, start at a specific column (character line offset) in the source code, and continue until the end of the line.
Some programming languages employ both block and line comments with different comment delimiters. For example, C++ has block comments delimited by /* and */ that can span multiple lines and line comments delimited by //. Other languages support only one type of comment. For example, Ada comments are line comments: they start with -- and continue to the end of the line.
Uses
How best to make use of comments is subject to dispute; different commentators have offered varied and sometimes opposing viewpoints.
There
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https://en.wikipedia.org/wiki/Jan%20Low
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Jan Low (born 1955) is an American food scientist. She is known for her work helping develop the biofortified orange-fleshed sweet potato at the CGIAR International Potato Center, for which she was a co-recipient of the 2016 World Food Prize alongside Maria Andrade, Robert Mwanga, and Howarth Bouis.
Early life and education
Low was born in 1955 in Denver, Colorado. She attended Pomona College and spent four years in Zaire with the Peace Corps before earning a doctorate in agricultural economics at Cornell University in 1994.
Career
After Cornell, Low began working at the Nairobi office of the CGIAR International Potato Center, a research center based in Lima, Peru. She helped develop the biofortified orange-fleshed sweet potato, which contains more vitamin A than the dominant variant, and can therefore be used to help alleviate the vitamin A deficiency common among children in the region.
Recognition
2016 World Food Prize (co-recipient)
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https://en.wikipedia.org/wiki/Pseudo%20Jahn%E2%80%93Teller%20effect
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The pseudo Jahn–Teller effect (PJTE), occasionally also known as second-order JTE, is a direct extension of the Jahn–Teller effect (JTE) where spontaneous symmetry breaking in polyatomic systems (molecules and solids) occurs even in nondegenerate electronic states under the influence of sufficiently low-lying excited states of appropriate symmetry. "The pseudo Jahn–Teller effect is the only source of instability and distortions of high-symmetry configurations of polyatomic systems in nondegenerate states, and it contributes significantly to the instability in degenerate states".
History
In their early 1957 paper on the (what is now called) pseudo Jahn–Teller effect (PJTE), Öpik and Pryce showed that a small splitting of the degenerate electronic term does not necessarily remove the instability and distortion of the polyatomic system induced by the Jahn–Teller effect (JTE), provided the splitting is sufficiently small (the two split states remain “pseudo degenerate”), and the vibronic coupling between them is strong enough. From another perspective, the idea of a "mix" of different electronic states induced by low-symmetry vibrations was introduced in 1933 by Herzberg and Teller to explore forbidden electronic transitions, and extended in the late 1950s by Murrell and Pople and by Liehr.
The role of excited states in softening the ground state with respect to distortions in benzene was demonstrated qualitatively by Longuet-Higgins and Salem by analyzing the π electron levels in the Hückel approximation, while a general second-order perturbation formula for such vibronic softening was derived by Bader in 1960. In 1961 Fulton and Gouterman presented a symmetry analysis of the two-level case in dimers and introduced the term "pseudo Jahn–Teller effect". The first application of the PJTE to solving a major solid-state structural problem with regard to the origin of ferroelectricity was published in 1966 by Isaac Bersuker, and the first book on the JTE covering the PJTE
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https://en.wikipedia.org/wiki/Primitive%20part%20and%20content
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In algebra, the content of a nonzero polynomial with integer coefficients (or, more generally, with coefficients in a unique factorization domain) is the greatest common divisor of its coefficients. The primitive part of such a polynomial is the quotient of the polynomial by its content. Thus a polynomial is the product of its primitive part and its content, and this factorization is unique up to the multiplication of the content by a unit of the ring of the coefficients (and the multiplication of the primitive part by the inverse of the unit).
A polynomial is primitive if its content equals 1. Thus the primitive part of a polynomial is a primitive polynomial.
Gauss's lemma for polynomials states that the product of primitive polynomials (with coefficients in the same unique factorization domain) also is primitive. This implies that the content and the primitive part of the product of two polynomials are, respectively, the product of the contents and the product of the primitive parts.
As the computation of greatest common divisors is generally much easier than polynomial factorization, the first step of a polynomial factorization algorithm is generally the computation of its primitive part–content factorization (see ). Then the factorization problem is reduced to factorize separately the content and the primitive part.
Content and primitive part may be generalized to polynomials over the rational numbers, and, more generally, to polynomials over the field of fractions of a unique factorization domain. This makes essentially equivalent the problems of computing greatest common divisors and factorization of polynomials over the integers and of polynomials over the rational numbers.
Over the integers
For a polynomial with integer coefficients, the content may be either the greatest common divisor of the coefficients or its additive inverse. The choice is arbitrary, and may depend on a further convention, which is commonly that the leading coefficient of the prim
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https://en.wikipedia.org/wiki/Taint%20checking
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Taint checking is a feature in some computer programming languages, such as Perl, Ruby or Ballerina designed to increase security by preventing malicious users from executing commands on a host computer. Taint checks highlight specific security risks primarily associated with web sites which are attacked using techniques such as SQL injection or buffer overflow attack approaches.
Overview
The concept behind taint checking is that any variable that can be modified by an outside user (for example a variable set by a field in a web form) poses a potential security risk. If that variable is used in an expression that sets a second variable, that second variable is now also suspicious. The taint checking tool can then proceed variable by variable forming a list of variables which are potentially influenced by outside input. If any of these variables is used to execute dangerous commands (such as direct commands to a SQL database or the host computer operating system), the taint checker warns that the program is using a potentially dangerous tainted variable. The computer programmer can then redesign the program to erect a safe wall around the dangerous input.
Taint checking may be viewed as a conservative approximation of the full verification of non-interference or the more general concept of secure information flow. Because information flow in a system cannot be verified by examining a single execution trace of that system, the results of taint analysis will necessarily reflect approximate information regarding the information flow characteristics of the system to which it is applied.
Example
The following dangerous Perl code opens a large SQL injection vulnerability by not checking the value of the $name variable:
#!/usr/bin/perl
my $name = $cgi->param("name"); # Get the name from the browser
...
$dbh->{TaintIn} = 1;
$dbh->execute("SELECT * FROM users WHERE name = '$name';"); # Execute an SQL query
If taint checking is turned on, Perl would refuse to run t
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https://en.wikipedia.org/wiki/COX14
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Cytochrome c oxidase assembly factor COX14 is a protein that in humans is encoded by the COX14 gene. This gene encodes a small single-pass transmembrane protein that localizes to mitochondria. This protein may play a role in coordinating the early steps of cytochrome c oxidase (COX; also known as complex IV) subunit assembly and, in particular, the synthesis and assembly of the COX I subunit of the holoenzyme. Mutations in this gene have been associated with mitochondrial complex IV deficiency. Alternative splicing results in multiple transcript variants.
Structure
The COX14 gene is located on the q arm of chromosome 12 at position 13.12 and it spans 8,476 base pairs. The COX14 gene produces a 6.6 kDa protein composed of 57 amino acids. COX14 is a component of the enzyme MITRAC (mitochondrial translation regulation assembly intermediate of cytochrome c oxidase complex) complex, and the structure contains a central transmembrane domain.
Function
The COX14 gene encodes for a core protein component of the MITRAC (mitochondrial translation regulation assembly intermediate of cytochrome c oxidase complex) complex, which is required for the proper regulation of complex IV assembly. Complex IV of the mitochondrial respiratory chain is essential in catalyzing the oxidation of cytochrome c by molecular oxygen. COX14 has been shown to contribute to the early stages of complex IV assembly by coelution with COX1 and COX4 for nucleation of the assembly. The protein participates in the coupling synthesis of COX1 followed by an assembly of nascent subunits into the holoenzyme complex IV. The knockdown of the protein COX14 involving small interfering RNA in regular human fibroblast has been shown to result in a complex IV defect with reduced activity.
Clinical significance
Variants of COX14 have been associated with the mitochondrial Complex IV deficiency, a deficiency in an enzyme complex of the mitochondrial respiratory chain which catalyzes the oxidation of cytochrome c utili
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https://en.wikipedia.org/wiki/Pubic%20arch
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The pubic arch, also referred to as the ischiopubic arch, is part of the pelvis. It is formed by the convergence of the inferior rami of the ischium and pubis on either side, below the pubic symphysis. The angle at which they converge is known as the subpubic angle.
Function
The pubic arch is one of three notches (the one in front) that separate the eminences of the lower circumference of the true pelvis.
Clinical significance
Subpubic angle
The subpubic angle (or pubic angle) is the angle in the human body as the apex of the pubic arch, formed by the convergence of the inferior rami of the ischium and pubis on either side. The subpubic angle is important in forensic anthropology, in determining the sex of someone from skeletal remains. A subpubic angle of 50–82 degrees indicates a male; an angle of 90 degrees indicates a female. Other sources operate with 50–60 degrees for males and 70–90 degrees in females. Women have wider hips, and thus a greater subpubic angle, in order to allow for child birth.
Intrapubic angle
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https://en.wikipedia.org/wiki/Topological%20quantum%20number
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In physics, a topological quantum number (also called topological charge) is any quantity, in a physical theory, that takes on only one of a discrete set of values, due to topological considerations. Most commonly, topological quantum numbers are topological invariants associated with topological defects or soliton-type solutions of some set of differential equations modeling a physical system, as the solitons themselves owe their stability to topological considerations. The specific "topological considerations" are usually due to the appearance of the fundamental group or a higher-dimensional homotopy group in the description of the problem, quite often because the boundary, on which the boundary conditions are specified, has a non-trivial homotopy group that is preserved by the differential equations. The topological quantum number of a solution is sometimes called the winding number of the solution, or, more precisely, it is the degree of a continuous mapping.
Recent ideas about the nature of phase transitions indicates that topological quantum numbers, and their associated solutions, can be created or destroyed during a phase transition.
Particle physics
In particle physics, an example is given by the Skyrmion, for which the baryon number is a topological quantum number. The origin comes from the fact that the isospin is modelled by SU(2), which is isomorphic to the 3-sphere and inherits the group structure of SU(2) through its bijective association, so the isomorphism is in the category of topological groups. By taking real three-dimensional space, and closing it with a point at infinity, one also gets a 3-sphere. Solutions to Skyrme's equations in real three-dimensional space map a point in "real" (physical; Euclidean) space to a point on the 3-manifold SU(2). Topologically distinct solutions "wrap" the one sphere around the other, such that one solution, no matter how it is deformed, cannot be "unwrapped" without creating a discontinuity in the solution.
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https://en.wikipedia.org/wiki/Clock%20drift
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Clock drift refers to several related phenomena where a clock does not run at exactly the same rate as a reference clock. That is, after some time the clock "drifts apart" or gradually desynchronizes from the other clock. All clocks are subject to drift, causing eventual divergence unless resynchronized. In particular, the drift of crystal-based clocks used in computers requires some synchronization mechanism for any high-speed communication. Computer clock drift can be utilized to build random number generators. These can however be exploited by timing attacks.
In non-atomic clocks
Everyday clocks such as wristwatches have finite precision. Eventually they require correction to remain accurate. The rate of drift depends on the clock's quality, sometimes the stability of the power source, the ambient temperature, and other subtle environmental variables. Thus the same clock can have different drift rates at different occasions.
More advanced clocks and old mechanical clocks often have some kind of speed trimmer where one can adjust the speed of the clock and thus correct for clock drift. For instance, in pendulum clocks the clock drift can be manipulated by slightly changing the length of the pendulum.
A quartz oscillator is less subject to drift due to manufacturing variances than the pendulum in a mechanical clock. Hence most everyday quartz clocks do not have an adjustable drift correction.
Atomic clocks
Atomic clocks are very precise and have nearly no clock drift. Even the Earth's rotation rate has more drift and variation in drift than an atomic clock due to tidal acceleration and other effects. The principle behind the atomic clock has enabled scientists to re-define the SI unit second in terms of exactly oscillations of the caesium-133 atom. The precision of these oscillations allows atomic clocks to drift roughly only one second in a hundred million years; as of 2015, the most accurate atomic clock loses one second every 15 billion years. The In
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https://en.wikipedia.org/wiki/Proteon
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Proteon, Inc. was a pioneering designer and manufacturer computer network equipment based in Westborough, Massachusetts. Proteon created the first commercial Token Ring products and created the first commercially available multiprotocol Internet router as well as the OSPF routing protocol.
History
Proteon designed and manufactured of some of the earliest commercial local area network and TCP/IP Internet Router products. Although founded in 1972 by Howard Salwen as communications consulting firm, Proteon became a manufacturer when they produced the first commercial Token Ring network interfaces and media access units in conjunction with MIT. In 1981, they released the 10Mbit/sec Pronet-10 Token Ring network. and evolved the speeds through 16 MBit/sec, 80 Mbit/sec and 100 Mbit/sec. IBM released a competing Token Ring system in 1984.
In 1986, Proteon released the first commercially available multi-protocol router, the p4200, based on the MIT multi-protocol router, using code developed by Noel Chiappa. Proteon's router products made them one of the key companies producing products to support the growing Internet, among rivals such as Cisco and Wellfleet Communications.
Proteon went public in 1991, issuing 3.1 million shares.
Proteon was renamed and relaunched as OpenROUTE Networks in 1998. OpenRoute Networks merged into Netrix in 1999. The combined company was rebranded as NX Networks. which was acquired by NSGDatacom in 2002, who dropped the NX Networks name in favor of Netrix.
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https://en.wikipedia.org/wiki/Hermitian%20matrix
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In mathematics, a Hermitian matrix (or self-adjoint matrix) is a complex square matrix that is equal to its own conjugate transpose—that is, the element in the -th row and -th column is equal to the complex conjugate of the element in the -th row and -th column, for all indices and :
or in matrix form:
Hermitian matrices can be understood as the complex extension of real symmetric matrices.
If the conjugate transpose of a matrix is denoted by then the Hermitian property can be written concisely as
Hermitian matrices are named after Charles Hermite, who demonstrated in 1855 that matrices of this form share a property with real symmetric matrices of always having real eigenvalues. Other, equivalent notations in common use are although in quantum mechanics, typically means the complex conjugate only, and not the conjugate transpose.
Alternative characterizations
Hermitian matrices can be characterized in a number of equivalent ways, some of which are listed below:
Equality with the adjoint
A square matrix is Hermitian if and only if it is equal to its adjoint, that is, it satisfies
for any pair of vectors where denotes the inner product operation.
This is also the way that the more general concept of self-adjoint operator is defined.
Reality of quadratic forms
An matrix is Hermitian if and only if
Spectral properties
A square matrix is Hermitian if and only if it is unitarily diagonalizable with real eigenvalues.'Applications
Hermitian matrices are fundamental to quantum mechanics because they describe operators with necessarily real eigenvalues. An eigenvalue of an operator on some quantum state is one of the possible measurement outcomes of the operator, which necessitates the need for operators with real eigenvalues.
Examples and solutions
In this section, the conjugate transpose of matrix is denoted as the transpose of matrix is denoted as and conjugate of matrix is denoted as
See the following example:
The diagonal elements m
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https://en.wikipedia.org/wiki/Party%20line%20%28telephony%29
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A party line (multiparty line, shared service line, party wire) is a local loop telephone circuit that is shared by multiple telephone service subscribers.
Party line systems were widely used to provide telephone service, starting with the first commercial switchboards in 1878. A majority of Bell System subscribers in the mid-20th century in the United States and Canada were served by party lines, which had a discount over individual service. During wartime shortages, these were often the only available lines.
British users similarly benefited from the party line discount. Farmers in rural Australia and South Africa used party lines, where a single line spanned miles from the nearest town to one property and on to the next.
History
Telephone companies offered party lines beginning in the late 1800s, although subscribers in all but the most rural areas may have had the option to upgrade to individual line service at an additional monthly charge. The service was common in sparsely populated areas where subscribers were spread across large distances. An example is Australia where these were operated by the Government Postmaster General's Department. In rural areas in the early 20th century, additional subscribers and telephones, often numbering several dozen, were frequently connected to the single loop available.
Party lines provided no privacy in communication. They were frequently used as a source of entertainment and gossip, as well as a means of quickly alerting entire neighbourhoods of emergencies such as fires, becoming a cultural fixture of rural areas for many decades.
The rapid growth of telephone service demand, especially after WWII, resulted in many party line installations in the middle of the 20th century in the United States. This often led to traffic congestion in the telephone network, as the line to a destination telephone was often busy. Nearly three-quarters of Pennsylvania residential service in 1943 was party line, with users encouraged
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https://en.wikipedia.org/wiki/Generation%20time
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In population biology and demography, generation time is the average time between two consecutive generations in the lineages of a population. In human populations, generation time typically has ranged from 20 to 30 years, with wide variation based on gender and society. Historians sometimes use this to date events, by converting generations into years to obtain rough estimates of time.
Definitions and corresponding formulas
The existing definitions of generation time fall into two categories: those that treat generation time as a renewal time of the population, and those that focus on the distance between individuals of one generation and the next. Below are the three most commonly used definitions:
The time it takes for the population to grow by a factor of its net reproductive rate
The net reproductive rate is the number of offspring an individual is expected to produce during its lifetime (a net reproductive rate of 1 means that the population is at its demographic equilibrium). This definition envisions the generation time as a renewal time of the population. It justifies the very simple definition used in microbiology ("the time it takes for the population to double", or doubling time) since one can consider that during the exponential phase of bacterial growth mortality is very low and as a result a bacterium is expected to be replaced by two bacteria in the next generation (the mother cell and the daughter cell). If the population dynamic is exponential with a growth rate , that is,
,
where is the size of the population at time , then this measure of the generation time is given by
.
Indeed, is such that , i.e. .
The average difference in age between parent and offspring
This definition is a measure of the distance between generations rather than a renewal time of the population. Since many demographic models are female-based (that is, they only take females into account), this definition is often expressed as a mother-daughter distance (the "ave
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https://en.wikipedia.org/wiki/Controversial%20Reddit%20communities
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Some communities on the social news site Reddit (known as "subreddits") are devoted to explicit, violent, or hateful material, and have been the topic of controversy. Controversial Reddit communities sometimes receive significant media coverage.
History
When Reddit was founded in 2005, there was only one shared space for all links, and subreddits did not exist. Subreddits were created later, but could only initially be created by Reddit administrators. In 2008, subreddit creation was opened to all users.
Reddit rose to infamy in October 2011, when a report by CNN showed that Reddit was harboring the r/Jailbait community, which was devoted to sharing suggestive or revealing photos of underage girls. After commenters were seen asking for nude photos of underage girls, and under significant external scrutiny, Reddit shut down r/Jailbait.
In 2012, the subreddit r/Creepshots received major backlash due to being a subreddit for sharing suggestive or revealing photos of women taken without their awareness or consent. Adrian Chen wrote a Gawker exposé of one of the subreddit's moderators and identified the person behind the account, starting discussion in the media about the ethics of anonymity and outing on the Internet.
Quarantining
In 2015, Reddit introduced a quarantine policy to make visiting certain subreddits more difficult. Visiting or joining a quarantined subreddit requires bypassing a warning prompt. In addition, quarantined subreddits do not appear in non-subscription based (aggregate) feeds such as r/all in order to prevent accidental viewing, do not generate revenue, and their user count is not visible. Since 2018, subreddits are allowed to appeal their quarantine.
Misinformation
Due to Reddit's decentralized moderation, user anonymity, and lack of fact-checking systems, the platform is highly prone to spreading misinformation and disinformation. It has been suggested that those who use Reddit should exercise caution in taking user-created unsourced
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https://en.wikipedia.org/wiki/Paleobiota%20of%20the%20Posidonia%20Shale
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The Sachrang Formation or "Posidonienschiefer" Formation (Whose Vulgar name is "Posidonia Shale") is a geological formation of southwestern Germany, northern Switzerland, northwestern Austria, southeast Luxembourg and the Netherlands, that spans about 3 million years during the Early Jurassic period (early Toarcian stage). It is known for its detailed fossils, especially sea fauna, listed below. Composed mostly by black shale, the formation is a Lagerstätte, where fossils show exceptional preservation (Including exquisite soft tissues), with a thickness that varies from about 1 m to about 40 m on the Rhine level, being on the main quarry at Holzmaden between 5 and 14 m. Some of the preserved material has been transformed into fossil hydrocarbon Jet, specially wood remains, used for jewelry. The exceptional preservation seen on the Posidonia Shale has been studied since the late 1800s, finding that a cocktail of chemical and environmental factors let to such an impressive conservation of the marine fauna. The most common theory is the changes in the oxygen level, where the different anoxic events of the Toarcian left oxygen-depleted bottom waters, with the biota dying and falling to the bottom without any predator able to eat the dead bodies.
Biological interaction frozen in time
Several animal behaviours have been recovered on the Posidonia Shale. The Monotis-Dactylioceras bed is one of them, as it shows an accumulation of the bivalves Meleagrinella substriata and the ammonite Dactylioceras, that were the most abundant representatives of its group on the Altdorf region, and were probably washed to near epicontinental waters by a rapid event, or as result of a large succession of events. This assemblage has been compared with modern Brazilian coastal Mangroves and also linked to Tsunami events.
Related to the Ammonite fauna, on Holzmaden there have been found several empty shells of this cephalopods, with associated crustaceans inside. The original specimen was repo
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https://en.wikipedia.org/wiki/GNOME%20Screensaver
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Up until GNOME 3.5, GNOME Screensaver was the GNOME project's official screen blanking and locking framework. With the release of GNOME 3.5.5, screen locking functionality became a function of GDM and GNOME Shell by default.
History
GNOME Screensaver continued to be used by the GNOME Fallback mode until GNOME Fallback was deprecated with the release of GNOME 3.8. GNOME Screensaver continues to be used in the GNOME Flashback session, a continuation of the GNOME Fallback mode. In October 2014, a member of the GNOME Flashback team requested maintainer-ship of GNOME Screensaver which would allow it to officially become part of the GNOME Flashback project.
On some GNOME-based Linux distributions, GNOME Screensaver was used instead of the framework that is a part of XScreenSaver. On these systems, the screen savers themselves still came from the XScreenSaver collection, GNOME Screensaver just provided the interface.
The GNOME Screensaver interface was designed for improved integration with the GNOME desktop, including themeability, language support, and human interface guidelines compliance. However, it no longer runs any screensavers and is more properly referred to as a screen blanker.
Compared to the front end included with XScreenSaver, GNOME Screensaver has a simplified interface but less customizability. For instance, users may not select which screensavers to select at random – either only one is selected or the program randomly selects from the whole list. In addition, the inability to configure individual screensavers and the developers' response to this issue has been criticized by some users. It also lacks a setting to control cycling through different screensavers.
In GNOME 3, GNOME Screensaver was drastically simplified, supporting only screen blanking and no graphical screen savers.
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https://en.wikipedia.org/wiki/The%20Copernican%20Revolution%20%28book%29
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The Copernican Revolution is a 1957 book by the philosopher Thomas Kuhn, in which the author provides an analysis of the Copernican Revolution, documenting the pre-Ptolemaic understanding through the Ptolemaic system and its variants until the eventual acceptance of the Keplerian system.
Kuhn argues that the Ptolemaic system provided broader appeal than a simple astronomical system but also became intertwined in broader philosophical and theological beliefs. Kuhn argues that this broader appeal made it more difficult for other systems to be proposed.
Summary
At the end of the book, Kuhn summarizes the achievements of Copernicus and Newton, while comparing the incompatibility of Newtonian physics with Aristotelian concepts that preceded the then new physics. Kuhn also noted that discoveries, such as that produced by Newton, were not in agreement with the prevailing worldview during his lifetime.
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https://en.wikipedia.org/wiki/Node%20deletion
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Node deletion is the procedure of removing a node from a network, where the node is either chosen randomly or directly. Node deletion is used to test the robustness and the attack tolerance of networks. Understanding how a network changes in response to node deletion is critical in many empirical networks. Application varies across many fields, including the breakdown of the World Wide Web via router removal, elimination of epidemics or fighting against criminal organizations.
Random deletion
Removing a node or multiple nodes randomly from a network means that the elimination of a set of nodes happens with a certain probability. The probability of deleting a node can follow any distribution; the most common is to assume a uniform distribution. The effect of the node deletion is highly dependent on the topology of the network, so it affects each empirical network differently.
Erdős-Rényi model
The effect on the network connectedness is measured with the diameter of the network (the length of the longest shortest path between two nodes). When we remove a fraction f of nodes, the diameter of the network increases monotonically with f. This is because each node has approximately the same degree and thus contributes to the interconnectedness by relatively the same amount.
Barabási-Albert model
The effect on a scale-free network is very different from what is experienced with random networks. As f increases, the diameter remains unchanged even on a 5% error level. This robustness comes from the presence of hubs in the network. As long as the hubs are not malfunctioning, the interconnectedness of the network is untouched.
Random removal from a growing network
When node deletion is combined with other processes, the topology of the network can change drastically. To illustrate this, consider the BA model. In each step add a new node with m links to the network, and also remove a node with probability r. This leads to different networks depending on m and r.
, Scale-fr
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https://en.wikipedia.org/wiki/Impedance%20analyzer
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An impedance analyzer is a type of electronic test equipment used to measure complex electrical impedance as a function of test frequency.
Impedance is an important parameter used to characterize electronic components, electronic circuits, and the materials used to make components. Impedance analysis can also be used to characterize materials exhibiting dielectric behavior such as biological tissue, foodstuffs or geological samples.
Impedance analyzers come in three distinct hardware implementations, and together these three implementations can probe from ultra low frequency to ultra high frequency and can measure impedances from µΩ to TΩ.
Operation
Impedance analyzers are a class of instruments which measure complex electrical impedance as a function of frequency. This involves the phase sensitive measurement of current and voltage applied to a device under test while the measurement frequency is varied over the course of the measurement. Key specifications of an impedance analyzer are the frequency range, impedance range, absolute impedance accuracy and phase angle accuracy. Further specifications include the ability to apply voltage bias and current bias while measuring, and the measurement speed.
Impedance analyzers typically offer highly accurate impedance measurements, e.g. with a basic accuracy of up to 0.05%, and a frequency measurement range from µHz to GHz. Impedance values can range over many decades from µΩ to TΩ, whereas the phase angle accuracy is in the range of 10 millidegree. Measured impedance values include absolute impedance, the real and imaginary part of the measured impedance and the phase between the voltage and current. Model-derived impedance parameters such as conductance, inductance and capacitance are calculated based on a replacement circuit model and subsequently displayed.
LCR meters also provide impedance measurement functionality, typically with similar accuracy but lower frequency range. The measurement frequency of LCR meters
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https://en.wikipedia.org/wiki/Rodolfo%20Llin%C3%A1s
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Rodolfo Llinás Riascos (born 16 December 1934) is a Colombian and American neuroscientist. He is currently the Thomas and Suzanne Murphy Professor of Neuroscience and Chairman Emeritus of the Department of Physiology & Neuroscience at the NYU School of Medicine. Llinás has published over 800 scientific articles.
Early life
Llinás was born in Bogotá, Colombia. He is the son of Jorge Enrique Llinás (a surgeon of Spanish descent, whose family arrived in Colombia at the end of the 19th century) and Bertha Riascos. He was motivated to study the brain by watching his grandfather Pablo Llinás Olarte working as a neuropsychiatrist. Llinás describes himself as a logical positivist.
Education and early research
Llinás went to the Gimnasio Moderno school in Bogotá and graduated as a medical doctor from the Pontifical Xavierian University in 1959. During his medical studies he had the opportunity to travel to Europe and there he met several researchers in Spain, France and finally Switzerland, where he participated in neurophysiology experiments with Dr. Walter Rudolf Hess, Nobel Prize in Physiology, Medicine, professor and director of the Department of the Institute of Physiology of the University of Zurich. Additionally, while studying medicine he made a theoretical thesis on the visual system under the tuition of neurosurgeon and neurophysiologist Fernando Rosas and the mathematician Carlo Federici at the National University of Colombia. He received his PhD in 1965 from the Australian National University working under Sir John Eccles.
Personal life
By graduation in Australia, he was very interested in the biological basis of the mind. During this time he met his future wife who was studying philosophy. His two sons, Drs. Rafael and Alexander Llinas, are also physicians. His wife, Gillian Llinas (née Kimber) is an Australian philosopher of mind.
Llinás was a scientific advisor during the establishment of an interactive science museum located in Bogotá, Colombia called Malo
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https://en.wikipedia.org/wiki/Fond
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In the culinary arts, fond is a contraction of fonds de cuisine which is loosely described as "the foundation and working capital of the kitchen". It refers to a flavorful liquid that is used as foundation (fondation in French, hence the abbreviation fond) for other preparations, such as stocks, broths, gravies and sauces.
In popular usage, the word fond is often conveniently used to refer to the stock made from a fond. It is also sometime used colloquially to refer to the solid bits of food found stuck to a pan after something was cooked; more technically, these bits are deglazed with a liquid in order to produce a fond.
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https://en.wikipedia.org/wiki/Ensonido
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Ensonido is a real-time post processing algorithm that allows users to play back MP3 Surround files in standard headphones.
Ensonido was developed by the Fraunhofer Society. It simulates the natural reception of surround sound by the human ear, which usually receives tones from surrounding loudspeakers and from reflections and echoes of the listening room. The out-of-head localization achieved that way increases the listening comfort noticeably in contrast to conventional stereo headphone listening with its in-head localization of all sounds. In version 3.0 of the Fraunhofer IIS MP3 Surround Player, Ensonido is replaced with newer mp3HD
External links
all4mp3.com Software, demos, information, and various mp3 resources
mp3surround.com - Demo content, information and evaluation software
The Register news story
Press Releases
mp3surrounded.com - First Blog in the internet about MP3 Surround-MP3 Surround Samples
Audio codecs
Digital audio
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https://en.wikipedia.org/wiki/Wine%20law
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Wine laws are legislation regulating various aspects of production and sales of wine. The purpose of wine laws includes combating wine fraud, by means of regulated protected designations of origin, labelling practices and classification of wine, as well as regulating allowed additives and procedures in winemaking and viticulture. Legislation affecting all kinds of alcohol beverages, such as the legal drinking age and licensing practices related to distribution and sales, are usually not considered wine laws.
Wine is regulated by regional, state, and local laws. The laws and their relative rigidity differ for New World and Old World wines. Old World wines tend to have more stringent regulations than New World wines. Various wine laws, however, may include appellation-based regulations that cover boundaries as well as permitted grape varieties and winemaking practice-such as the French Appellation d'origine contrôlée (AOC), Italian Denominazione di origine controllata (DOC), Spanish Denominación de Origen (DO) and Portuguese Denominação de Origem Controlada (DOC). In some New World wine regions, such as the United States and Australia, the wine laws of the appellation systems (American Viticultural Area (AVA) and Australian Geographical Indication (GIs)) only pertain to boundary specifics and guaranteeing that a certain percentage of grapes come from the area listed on the wine label.
Some wine laws are established by local governments and are specific to that wine region, such as the 1954 municipal decree in the village of Châteauneuf-du-Pape that banned the overhead flying, landing or taking off of flying saucers in the commune which could negatively affect the region's vineyards and wine production.
History
The oldest known wine laws were created by the Roman emperor Domitian, who c. 92 issued an edict that banned the plantings of any new vineyards in Italy and ordered the uprooting of half of the vineyards in Roman provinces. The purpose of the edict was to i
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https://en.wikipedia.org/wiki/Bacillus%20spore%20morphogenesis%20and%20germination%20holin%20family
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The Bacillus Spore Morphogenesis and Germination Holin (BSH) Family (TC# 1.E.23) is a family of proteins named after a holin in Bacillus subtilis described to be involved in spore morphogenesis and germination by Real et al (2005). The gene encoding this holin is ywcE. Mutants lacking this gene or its product have spores that exhibit outer coat defects. These spores lack the characteristic striatal pattern resulting in the failure of the outer coat to attach to the underlying inner coat. Finally, the mutant spores accumulate reduced amounts of dipicolinic acid. BSH proteins average about 90 amino acyl residues in length and exhibit 3 transmembrane segments (TMSs). A representative list of homologous proteins, found only in Bacillus species, is available in the Transporter Classification Database.
See also
Holin
Lysin
Transporter Classification Database
Further reading
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https://en.wikipedia.org/wiki/National%20Institute%20of%20Chemical%20Physics%20and%20Biophysics
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National Institute of Chemical Physics and Biophysics (NICPB; Estonian Keemilise ja Bioloogilise Füüsika Instituut, or KBFI) is public non-profit research institute that carries out fundamental and applied research and engages in the development of the novel directions in material sciences, physics, chemistry, gene- and biotechnology, environmental technology, and computer science. in Estonia, Tallinn at the address Akadeemia tee 23.
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https://en.wikipedia.org/wiki/Bioluminescence
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Bioluminescence is the production and emission of light by living organisms. It is a form of chemiluminescence. Bioluminescence occurs widely in marine vertebrates and invertebrates, as well as in some fungi, microorganisms including some bioluminescent bacteria, and terrestrial arthropods such as fireflies. In some animals, the light is bacteriogenic, produced by symbiotic bacteria such as those from the genus Vibrio; in others, it is autogenic, produced by the animals themselves.
In a general sense, the principal chemical reaction in bioluminescence involves a light-emitting molecule and an enzyme, generally called luciferin and luciferase, respectively. Because these are generic names, luciferins and luciferases are often distinguished by the species or group, e.g. firefly luciferin. In all characterized cases, the enzyme catalyzes the oxidation of the luciferin.
In some species, the luciferase requires other cofactors, such as calcium or magnesium ions, and sometimes also the energy-carrying molecule adenosine triphosphate (ATP). In evolution, luciferins vary little: one in particular, coelenterazine, is found in 11 different animal phyla, though in some of these, the animals obtain it through their diet. Conversely, luciferases vary widely between different species, which is evidence that bioluminescence has arisen over 40 times in evolutionary history.
Both Aristotle and Pliny the Elder mentioned that damp wood sometimes gives off a glow. Many centuries later Robert Boyle showed that oxygen was involved in the process, in both wood and glowworms. It was not until the late nineteenth century that bioluminescence was properly investigated. The phenomenon is widely distributed among animal groups, especially in marine environments. On land it occurs in fungi, bacteria and some groups of invertebrates, including insects.
The uses of bioluminescence by animals include counterillumination camouflage, mimicry of other animals, for example to lure prey, and signal
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https://en.wikipedia.org/wiki/Energy-based%20model
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An energy-based model (EBM) is a form of generative model (GM) imported directly from statistical physics to learning. GMs learn an underlying data distribution by analyzing a sample dataset. Once trained, a GM can produce other datasets that also match the data distribution. EBMs provide a unified framework for many probabilistic and non-probabilistic approaches to such learning, particularly for training graphical and other structured models.
An EBM learns the characteristics of a target dataset and generates a similar but larger dataset. EBMs detect the latent variables of a dataset and generate new datasets with a similar distribution.
Target applications include natural language processing, robotics and computer vision.
History
The term "energy-based models" was first coined in a JMLR paper where the authors defined a generalisation of independent components analysis to the overcomplete setting using EBMs.
Other early work on EBMs proposed models that represented energy as a composition of latent and observable variables. EBMs surfaced in 2003.
Approach
EBMs capture dependencies by associating an unnormalized probability scalar (energy) to each configuration of the combination of observed and latent variables. Inference consists of finding (values of) latent variables that minimize the energy given a set of (values of) the observed variables. Similarly, the model learns a function that associates low energies to correct values of the latent variables, and higher energies to incorrect values.
Traditional EBMs rely on stochastic gradient-descent (SGD) optimization methods that are typically hard to apply to high-dimension datasets. In 2019, OpenAI publicized a variant that instead used Langevin dynamics (LD). LD is an iterative optimization algorithm that introduces noise to the estimator as part of learning an objective function. It can be used for Bayesian learning scenarios by producing samples from a posterior distribution.
EBMs do not require that e
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https://en.wikipedia.org/wiki/Neurosarcoidosis
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Neurosarcoidosis (sometimes shortened to neurosarcoid) refers to a type of sarcoidosis, a condition of unknown cause featuring granulomas in various tissues, in this type involving the central nervous system (brain and spinal cord). Neurosarcoidosis can have many manifestations, but abnormalities of the cranial nerves (a group of twelve nerves supplying the head and neck area) are the most common. It may develop acutely, subacutely, and chronically. Approximately 5–10 percent of people with sarcoidosis of other organs (e.g. lung) develop central nervous system involvement. Only 1 percent of people with sarcoidosis will have neurosarcoidosis alone without involvement of any other organs. Diagnosis can be difficult, with no test apart from biopsy achieving a high accuracy rate. Treatment is with immunosuppression. The first case of sarcoidosis involving the nervous system was reported in 1905.
Signs and symptoms
Neurological
Abnormalities of the cranial nerves are present in 50–70 percent of cases. The most common abnormality is involvement of the facial nerve, which may lead to reduced power on one or both sides of the face (65 percent resp 35 percent of all cranial nerve cases), followed by reduction in visual perception due to optic nerve involvement. Rarer symptoms are double vision (oculomotor nerve, trochlear nerve or abducens nerve), decreased sensation of the face (trigeminal nerve), hearing loss or vertigo (vestibulocochlear nerve), swallowing problems (glossopharyngeal nerve) and weakness of the shoulder muscles (accessory nerve) or the tongue (hypoglossal nerve). Visual problems may also be the result of papilledema (swelling of the optic disc) due to obstruction by granulomas of the normal cerebrospinal fluid (CSF) circulation.
Seizures (mostly of the tonic-clonic/"grand mal" type) are present in about 15 percent and may be the presenting phenomenon in 10 percent.
Meningitis (inflammation of the lining of the brain) occurs in 3–26 percent of cases. Sym
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https://en.wikipedia.org/wiki/Fortnite%20Holocaust%20Museum
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The Fortnite Holocaust Museum, also known as Voices of the Forgotten, is a virtual museum for the video game Fortnite Creative, designed by Luc Bernard and approved by publisher Epic Games. It became available in August 2023.
Content
The museum features photographs and plaques highlighting people who resisted the Nazis, and show visitors examples of Nazi atrocities such as the Kristallnacht. One room in the museum features a "Hall of Historical Figures" featuring people such as Marianne Cohn and Abdol Hossein Sardari.
On August 3, 2023, The Jewish Chronicle uploaded a trailer for the Fortnite Holocaust Museum, showcasing the displays and the first person & single player perspective of the exhibit. Designer Luc Bernard cited his fears of the misuse of AI as being a driving force behind his attempts to build a virtual Holocaust exhibit.
Response
Fortnite publisher Epic Games approved the project in August 2023. Some critics of the museum have highlighted issues with Fortnites virtual Martin Luther King Jr. Museum in 2021, where Epic Games disabled emotes following players recording themselves dancing to King's "I Have a Dream" speech. In response to concerns about vandalism of the memorial, Bernard said that many of the game's features would be disabled, arguing that this would make the Fortnite Holocaust Museum better protected than real world monuments.
The Christian Science Monitor commented on the choice of Fortnite as a venue for a Holocaust Museum:"Fortnite is not an obvious location for a museum about genocide; the popular battle royal game is probably known best for its extensive suite of goofy, gesticulating characters. It’s a place where you can find Batman duking it out with a sentient banana peel, and then swinging his arms in a viral victory dance known as the griddy."
Release
The release of the Fortnite Holocaust Museum was delayed following concerns of vandalism by Neo-Nazi internet trolls, particularly after comments from American Holocaust den
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https://en.wikipedia.org/wiki/Eternal%20September
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Eternal September or the September that never ended is Usenet slang for a period beginning around 1993 when Internet service providers began offering Usenet access to many new users. The flood of new users overwhelmed the existing culture for online forums and the ability to enforce existing norms. AOL followed with their Usenet gateway service in March 1994, leading to a constant stream of new users. Hence, from the early Usenet point of view, the influx of new users in September 1993 never ended.
History
During the 1980s and early 1990s, Usenet and the Internet were generally the domain of dedicated computer professionals and hobbyists; new users joined slowly, in small numbers, and observed and learned the social conventions of online interaction without having much of an impact on the experienced users. The only exception to this was September of every year, when large numbers of first-year college students gained access to the Internet and Usenet through their universities. These large groups of new users who had not yet learned online etiquette created a nuisance for the experienced users, who came to dread September every year. Once ISPs like AOL made Internet access widely available for home users, a continuous influx of new users began, making it feel like it was always "September" to the more experienced users.
The full phrase appears to have evolved over a series of months on two separate alt.folklore newsgroups where a number of threads exist lamenting what they saw as an increase in low-quality posts across various newsgroups. Several members of the newsgroups referenced aspects of the "September" issue, typically in a joking manner.
In a thread on January 8, 1994, Joel Furr cross-posted asking "Is it just me, or has Delphi unleashed a staggering amount of weirdos on the net?", which garnered a reply from Karl Reinsch "Of course it's perpetually September for Delphi users, isn't it?" The day before, Furr had also posted the same message to alt.fol
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https://en.wikipedia.org/wiki/Sharktopus%20vs.%20Pteracuda
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Sharktopus vs. Pteracuda is the sequel to the 2010 SyFy original monster film Sharktopus and premiered on August 2, 2014. The film was produced by Roger Corman, who directed the Conan O'Brien cameo, and stars Robert Carradine, Katie Savoy, and Rib Hillis. O'Brien makes his acting debut in a scene described as "truly violent, patently disgusting and darkly humorous". It is the second film in the Sharktopus franchise.
Plot
Sometime after the events of the first film, marine biologist Lorena Christmas (Katie Savoy) discovers an egg sac containing a baby Sharktopus in the ocean, left behind by the destruction of the original Sharktopus.
Sometime later, Dr. Rico Symes (Robert Carradine), CEO of Symodyne (the company that originally created Sharktopus), releases a barracuda-pterodactyl hybrid creature known as Pteracuda, intended for military use, above the desert against the advice of head of security Hamilton (Rib Hillis). The Pteracuda, controlled with a computer chip in its brain, is secretly hacked by a scientist at Symodyne named Vladimir Futon to terrorize populated areas. The Pteracuda is directed towards the Symodyne lab, and kills a worker before Hamilton scares it off. Futon flees the scene and continues to control the Pteracuda from his car.
Hamilton and his team of military commandos engage in battle with the Pteracuda in a helicopter. Symes discovers that Pteracuda's computer chip has been hacked, and reports this information to Hamilton. The Pteracuda then causes the helicopter to crash in the ocean, killing everybody except Hamilton. Futon – while driving his car – loses the Pteracuda's signal after spilling a beverage on his computer keyboard and then crashing his car, leaving Pteracuda on his own command.
Meanwhile, Lorena is working at a water park/aquarium owned by her uncle, greedy business mogul Munoz, and is currently training the now fully grown Sharktopus. After two customers threaten to give Munoz a one star review, he shows them the Sharktop
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https://en.wikipedia.org/wiki/3-subset%20meet-in-the-middle%20attack
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The 3-subset meet-in-the-middle (hereafter shortened MITM) attack is a variant of the generic meet-in-the-middle attack, which is used in cryptology for hash and block cipher cryptanalysis. The 3-subset variant opens up the possibility to apply MITM attacks on ciphers, where it is not trivial to divide the keybits into two independent key-spaces, as required by the MITM attack.
The 3-subset variant relaxes the restriction for the key-spaces to be independent, by moving the intersecting parts of the keyspaces into a subset, which contains the keybits common between the two key-spaces.
History
The original MITM attack was first suggested in an article by Diffie and Hellman in 1977, where they discussed the cryptanalytic properties of DES. They argued that the keysize of DES was too small, and that reapplying DES multiple times with different keys could be a solution to the key-size; however, they advised against using double-DES and suggested triple-DES as a minimum, due to MITM attacks (Double-DES is very susceptible to a MITM attack, as DES could easily be split into two subciphers (the first and second DES encryption) with keys independent of one another, thus allowing for a basic MITM attack that reduces the computational complexity from to .
Many variations has emerged, since Diffie and Hellman suggested MITM attacks. These variations either makes MITM attacks more effective, or allows them to be used in situations, where the basic variant cannot. The 3-subset variant was shown by Bogdanov and Rechberger in 2011, and has shown its use in cryptanalysis of ciphers, such as the lightweight block-cipher family KTANTAN.
Procedure
As with general MITM attacks, the attack is split into two phases: A key-reducing phase and a key-verification phase. In the first phase, the domain of key-candidates is reduced, by applying the MITM attack. In the second phase, the found key-candidates are tested on another plain-/ciphertext pair to filter away the wrong key(s).
Key-
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https://en.wikipedia.org/wiki/Poincar%C3%A9%20separation%20theorem
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In mathematics, the Poincaré separation theorem, also known as the Cauchy interlacing theorem, gives some upper and lower bounds of eigenvalues of a real symmetric matrix B'AB that can be considered as the orthogonal projection of a larger real symmetric matrix A onto a linear subspace spanned by the columns of B. The theorem is named after Henri Poincaré.
More specifically, let A be an n × n real symmetric matrix and B an n × r semi-orthogonal matrix such that B'B = Ir. Denote by , i = 1, 2, ..., n and , i = 1, 2, ..., r the eigenvalues of A and B'AB, respectively (in descending order). We have
Proof
An algebraic proof, based on the variational interpretation of eigenvalues, has been published in Magnus' Matrix Differential Calculus with Applications in Statistics and Econometrics. From the geometric point of view, B'AB can be considered as the orthogonal projection of A onto the linear subspace spanned by B, so the above results follow immediately.
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https://en.wikipedia.org/wiki/Tupper%27s%20self-referential%20formula
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Tupper's self-referential formula is a formula that visually represents itself when graphed at a specific location in the (x, y) plane.
History
The formula was defined by Jeff Tupper and appears as an example in Tupper's 2001 SIGGRAPH paper on reliable two-dimensional computer graphing algorithms. This paper discusses methods related to the GrafEq formula-graphing program developed by Tupper.
Although the formula is called "self-referential", Tupper did not name it as such.
Formula
The formula is an inequality defined as:
where denotes the floor function, and mod is the modulo operation.
Plots
Let equal the following 543-digit integer:
960939379918958884971672962127852754715004339660129306651505519271702802395266424689642842174350718121267153782770623355993237280874144307891325963941337723487857735749823926629715517173716995165232890538221612403238855866184013235585136048828693337902491454229288667081096184496091705183454067827731551705405381627380967602565625016981482083418783163849115590225610003652351370343874461848378737238198224849863465033159410054974700593138339226497249461751545728366702369745461014655997933798537483143786841806593422227898388722980000748404719
Graphing the set of points in and , results in the following plot:
The formula is a general-purpose method of decoding a bitmap stored in the constant , and it could be used to draw any other image. When applied to the unbounded positive range , the formula tiles a vertical swath of the plane with a pattern that contains all possible 17-pixel-tall bitmaps. One horizontal slice of that infinite bitmap depicts the drawing formula itself, but this is not remarkable, since other slices depict all other possible formulae that might fit in a 17-pixel-tall bitmap. Tupper has created extended versions of his original formula that rule out all but one slice.
The constant is a simple monochrome bitmap image of the formula treated as a binary number and multiplied by 17. If is divided by 17,
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https://en.wikipedia.org/wiki/ANO5
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Anoctamin 5 (ANO5) is a protein that in humans is encoded by the ANO5 gene.
Function
The ANO5 gene provides instructions for making a protein called anoctamin-5. While the specific function of this protein is not well understood, it belongs to a family of proteins, called anoctamins, that act as chloride channels. Chloride channels, which transport negatively charged chlorine atoms (chloride ions) in and out of cells, play a key role in a cell's ability to generate and transmit electrical signals. Most anoctamin proteins function as chloride channels that are turned on (activated) in the presence of positively charged calcium atoms (calcium ions); these channels are known as calcium-activated chloride channels. The mechanism for this calcium activation is unclear. Anoctamin proteins are also involved in maintaining the membrane that surrounds cells and repairing the membrane if damaged.
The anoctamin-5 protein is most abundant in muscles used for movement (skeletal muscles). For the body to move normally, skeletal muscles must tense (contract) and relax in a coordinated way. The regulation of chloride flow within muscle cells plays a role in controlling muscle contraction and relaxation.
The anoctamin-5 protein is also found in other cells including heart (cardiac) muscle cells and bone cells. The anoctamin-5 protein may be important for the development of muscle and bone before birth.
Diseases associated with ANO5 mutations
Gnathodiaphyseal dysplasia (GDD), a rare skeletal syndrome.
Limb Girdle Muscular Dystrophy 2L (LGMD2L, Autosomal Recessive 12) and Miyoshi Muscular Dystrophy 3 (MMD3). These forms of muscular dystrophy are inherited in an autosomal recessive pattern. To be affected, a person must have mutations on both copies of the gene. Males and females are equally likely to be affected.
Typical Symptoms
GDD causes bone fragility, sclerosis of tubular bones, and cemento-osseous lesions of the jawbone. Patients also experience frequent bone fractures.
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https://en.wikipedia.org/wiki/Catamount%20%28operating%20system%29
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Catamount is an operating system for supercomputers.
Catamount is a lightweight kernel that provides basic functionality and aims for efficiency. The roots of Catamount go back to 1991 when SUNMOS was developed by Sandia National Laboratories and the University of New Mexico as a lightweight operating system. The Cray XT3 uses Catamount on compute nodes and Linux on server nodes.
A case study by the IEEE assessed the performance of a particle transport code on AWE's Cray XT3 8,000-core supercomputer while running images of the Catamount and the Cray Linux Environment (CLE) operating systems. This work demonstrated that by running a number of small benchmarks on a test machine it is possible to speculate as to the performance impact of upgrading from one operating system to another on the system as a whole. The study's findings allows researchers to minimise system downtime while exploring software-system upgrades. The results show that benchmark tests run on less than 256 cores would suggest that the impact of upgrading the operating system to CLE was less than 10%.
See also
Compute Node Linux
Cray XT3
Cray Inc. supercomputers
Timeline of operating systems
CNK operating system
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https://en.wikipedia.org/wiki/Pruinescence
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Pruinescence , or pruinosity, is a "frosted" or dusty-looking coating on top of a surface. It may also be called a pruina (plural: pruinae), from the Latin word for hoarfrost. The adjectival form is pruinose .
Entomology
In insects, a "bloom" caused by wax particles on top of an insect's cuticle covers up the underlying coloration, giving a dusty or frosted appearance. The pruinescence is commonly white to pale blue in color but can be gray, pink, purple, or red; these colors may be produced by Tyndall scattering of light. When pale in color, pruinescence often strongly reflects ultraviolet.
Pruinescence is found in many species of Odonata, particularly damselflies of the families Lestidae and Coenagrionidae, where it occurs on the wings and body. Among true dragonflies it is most common on male Libellulidae (skimmers).
In the common whitetail and blue dasher dragonflies (Plathemis lydia and Pachydiplax longipennis), males display the pruinescence on the back of the abdomen to other males as a territorial threat. Other Odonata may use pruinescence to recognize members of their own species or to cool their bodies by reflecting radiation away.
Plants, fungi, and lichens
The term pruinosity is also applied to "blooms" on plants—for example, on the skin of grapes—and to powderings on the cap and stem of mushrooms, which can be important for identification.
An epinecral layer is "a layer of horny dead fungal hyphae with indistinct lumina in or near the cortex above the algal layer".
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https://en.wikipedia.org/wiki/Further%20research%20is%20needed
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The phrases "further research is needed" (FRIN), "more research is needed" and other variants are commonly used in research papers. The cliché is so common that it has attracted research, regulation and cultural commentary.
Meaning
Some research journals have banned the phrase "more research is needed" on the grounds that it is redundant; it is almost always true and fits almost any article, and so can be taken as understood.
A 2004 metareview by the Cochrane collaboration of their own systematic medical reviews found that 93% of the reviews studied made indiscriminate FRIN-like statements, reducing their ability to guide future research. The presence of FRIN had no correlation with the strength of the evidence against the medical intervention. Authors who thought a treatment was useless were just as likely to recommend researching it further.
Indeed, authors may recommend "further research" when, given the existing evidence, further research would be extremely unlikely to be approved by an ethics committee.
Studies finding that a treatment has no noticeable effects are sometimes greeted with statements that "more research is needed" by those convinced that the treatment is effective, but the effect has not yet been found. Since even the largest study can never rule out an infinitesimal effect, an effect can only ever be shown to be insignificant, not non-existent. Similarly, Trish Greenhalgh, Professor of Primary Care Health Sciences at the University of Oxford, argues that FRIN is often used as a way in which a "[l]ack of hard evidence to support the original hypothesis gets reframed as evidence that investment efforts need to be redoubled", and a way to avoid upsetting hopes and vested interests. She has also described FRIN as "an indicator that serious scholarly thinking on the topic has ceased", saying that "it is almost never the only logical conclusion that can be drawn from a set of negative, ambiguous, incomplete or contradictory data."
Addressing the
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https://en.wikipedia.org/wiki/Semantic%20analysis%20%28computational%29
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Semantic analysis (computational) within applied linguistics and computer science, is a composite of semantic analysis and computational components. Semantic analysis refers to a formal analysis of meaning, and computational refers to approaches that in principle support effective implementation in digital computers.
See also
Computational semantics
Natural language processing
Semantic analytics
Semantic analysis (machine learning)
Semantic Web
SemEval
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https://en.wikipedia.org/wiki/B%C3%B6hm%20tree
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In the study of denotational semantics of the lambda calculus, Böhm trees, Lévy-Longo trees, and Berarducci trees are (potentially infinite) tree-like mathematical objects that capture the "meaning" of a term up to some set of "meaningless" terms.
Motivation
A simple way to read the meaning of a computation is to consider it as a mechanical procedure consisting of a finite number of steps that, when completed, yields a result. In particular, considering the lambda calculus as a rewriting system, each beta reduction step is a rewrite step, and once there are no further beta reductions the term is in normal form. We could thus, naively following Church's suggestion, say the meaning of a term is its normal form, and that terms without a normal form are meaningless. For example the meanings of I = λx.x and I I are both I. This works for any strongly normalizing subset of the lambda calculus, such as a typed lambda calculus.
This naive assignment of meaning is however inadequate for the full lambda calculus. The term Ω =(λx.x x)(λx.x x) does not have a normal form, and similarly the term X=λx.xΩ does not have a normal form. But the application Ω (K I), where K denotes the standard lambda term λx.λy.x, reduces only to itself, whereas the application X (K I) reduces with normal order reduction to I, hence has a meaning. We thus see that not all non-normalizing terms are equivalent. We would like to say that Ω is less meaningful than X because applying X to a term can produce a result but applying Ω cannot.
In the infinitary lambda calculus, the term N N, where N = λx.I(xx), reduces to both to I (I (...)) and Ω. Hence there are also issues with confluence of normalization.
Sets of meaningless terms
We define a set of meaningless terms as follows:
Root-activeness: Every root-active term is in . A term is root-active if for all there exists a redex such that .
Closure under β-reduction: For all , if then .
Closure under substitution: For all and substitution
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https://en.wikipedia.org/wiki/Edible%20lichen
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Edible lichens are lichens that have a cultural history of use as a food. Although almost all lichen are edible (with some notable poisonous exceptions like the wolf lichen, powdered sunshine lichen, and the ground lichen), not all have a cultural history of usage as an edible lichen. Often lichens are merely famine foods eaten in times of dire needs, but in some cultures lichens are a staple food or even a delicacy.
Uses
Although there are many lichen species throughout the world, only a few species of lichen are known to be both edible and provide any nutrition. Two problems often encountered with eating lichens is that they usually contain mildly toxic secondary compounds, and that lichen polysaccharides are generally indigestible to humans. Many human cultures have discovered preparation techniques to overcome these problems. Lichens are often thoroughly washed, boiled, or soaked in ash water to help remove secondary compounds.
Recent analytics within the field have identified 15 kinds of edible lichen, which have been mostly found in China. Due to its rubbery consistency, individuals within China fry, boil, and pressure-cook edible lichens. Further, edible lichens can be made into beverages such as tea.
In the past Iceland moss (Cetraria islandica) was an important human food in northern Europe and Scandinavia, and was cooked in many different ways, such as bread, porridge, pudding, soup, or salad. Bryoria fremontii was an important food in parts of North America, where it was usually pitcooked. It is even featured in a Secwepemc story. Reindeer lichen (Cladonia spp.) is a staple food of reindeer and caribou in the Arctic. Northern peoples in North America and Siberia traditionally eat the partially digested lichen after they remove it from the rumen of caribou that have been killed. It is often called 'stomach icecream'. Rock tripe (Umbilicaria spp. and Lasalia spp.) is a lichen that has frequently been used as an emergency food in North America.
One spe
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https://en.wikipedia.org/wiki/Esther%20M.%20Conwell
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Esther Marley Conwell (May 23, 1922 – November 16, 2014) was a pioneering American chemist and physicist, best known for the Conwell-Weisskopf theory that describes how electrons travel through semiconductors, a breakthrough that helped revolutionize modern computing. During her life, she was described as one of the most important women in science.
Conwell studied properties of semiconductors and organic conductors, especially electron transport. In 1990, she became an adjunct professor at the University of Rochester while still working at Xerox. In 1998, she joined the University of Rochester faculty full-time as a professor of chemistry, focused on the flow of electrons through DNA.
Conwell held four patents and published more than 270 papers and multiple textbooks over the course of her career. Her textbook, High Field Transport in Semiconductors, became the authoritative text in the field. She received numerous honors, including the National Medal of Science in 2009.
Education
Conwell obtained a physics B.A. from Brooklyn College in 1942. She then went to the University of Rochester to complete a M.S. in physics in 1945 with Victor Weisskopf. She initially planned to do a Ph.D. at Rochester, but since her adviser left to work at Los Alamos after her first year there, she completed her masters and obtained a Ph.D. at a later point in time. Conwell collaborated with Karl Lark-Horovitz and Vivian Johnson at Purdue University on silicon and germanium semiconductor physics. Her masters was initially classified then finally declassified in 1945 and subsequently her M.S. was awarded in which she determined the Conwell-Weisskopf theory. Conwell received her physics Ph.D. in 1948, from the University of Chicago under the advisement of Nobel Laureate Subrahmanyan Chandrasekhar at Yerkes Observatory and was also an assistant to Enrico Fermi. She was a teaching assistant at Chicago and graded the work of Nobel Laureates such as Chen-Ning Yang and Owen Chamberlain.
Care
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https://en.wikipedia.org/wiki/Eye%20relief
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The eye relief of an optical instrument (such as a telescope, a microscope, or binoculars) is the distance from the last surface of an eyepiece within which the user's eye can obtain the full viewing angle. If a viewer's eye is outside this distance, a reduced field of view will be obtained. The calculation of eye relief is complex, though generally, the higher the magnification and the larger the intended field of view, the shorter the eye relief.
Eye relief and exit pupil
The eye relief property should not be confused with the exit pupil width of an instrument: that is best described as the width of the cone of light that is available to the viewer at the exact eye relief distance. An exit pupil larger than the observer's pupil wastes some light, but allows for some fumbling in side-to-side movement without vignetting or clipping. Conversely, an exit pupil smaller than the eye's pupil will have all of its available light used, but since it cannot tolerate much side-to-side error in eye alignment, will often result in a vignetted or clipped image.
The exit pupil width of say, a binocular, can be calculated as the objective diameter divided by the magnification, and gives the width of the exit cone of light in the same dimensions as the objective. For example, a 10 × 42 binocular has a 4.2 mm wide exit cone, and fairly comfortable for general use, whereas doubling the magnification with a zoom feature to 20 × results in a much more critical 2.1 mm exit cone.
Eye relief distance can be particularly important for eyeglass wearers and shooters. The eye of an eyeglass wearer is typically further from the eyepiece, so that user needs a longer eye relief in order to still see the entire field of view. A simple practical test as to whether or not spectacles limit the field of view can be conducted by viewing first without spectacles and then again with them. Ideally there should be no difference in the field.
For a shooter, eye relief is also a safety consideration. If
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https://en.wikipedia.org/wiki/Parietal%20bone
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The parietal bones () are two bones in the skull which, when joined at a fibrous joint, form the sides and roof of the cranium. In humans, each bone is roughly quadrilateral in form, and has two surfaces, four borders, and four angles. It is named from the Latin paries (-ietis), wall.
Surfaces
External
The external surface [Fig. 1] is convex, smooth, and marked near the center by an eminence, the parietal eminence (tuber parietale), which indicates the point where ossification commenced.
Crossing the middle of the bone in an arched direction are two curved lines, the superior and inferior temporal lines; the former gives attachment to the temporal fascia, and the latter indicates the upper limit of the muscular origin of the temporal muscle.
Above these lines the bone is covered by a tough layer of fibrous tissue – the epicranial aponeurosis; below them it forms part of the temporal fossa, and affords attachment to the temporal muscle.
At the back part and close to the upper or sagittal border is the parietal foramen which transmits a vein to the superior sagittal sinus, and sometimes a small branch of the occipital artery; it is not constantly present, and its size varies considerably.
Internal
The internal surface [Fig. 2] is concave; it presents depressions corresponding to the cerebral convolutions, and numerous furrows (grooves) for the ramifications of the middle meningeal artery; the latter run upward and backward from the sphenoidal angle, and from the central and posterior part of the squamous border.
Along the upper margin is a shallow groove, which, together with that on the opposite parietal, forms a channel, the sagittal sulcus, for the superior sagittal sinus; the edges of the sulcus afford attachment to the falx cerebri.
Near the groove are several depressions, best marked in the skulls of old persons, for the arachnoid granulations (Pacchionian bodies).
In the groove is the internal opening of the parietal foramen when that aperture exists.
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https://en.wikipedia.org/wiki/Online%20magazine
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An online magazine is a magazine published on the Internet, through bulletin board systems and other forms of public computer networks. One of the first magazines to convert from a print magazine format to an online only magazine was the computer magazine Datamation. Some online magazines distributed through the World Wide Web call themselves webzines. An ezine (also spelled e-zine) is a more specialized term appropriately used for small magazines and newsletters distributed by any electronic method, for example, by email. Some social groups may use the terms cyberzine and hyperzine when referring to electronically distributed resources. Similarly, some online magazines may refer to themselves as "electronic magazines", "digital magazines", or "e-magazines" to reflect their readership demographics or to capture alternative terms and spellings in online searches.
An online magazine shares some features with a blog and also with online newspapers, but can usually be distinguished by its approach to editorial control. Magazines typically have editors or editorial boards who review submissions and perform a quality control function to ensure that all material meets the expectations of the publishers (those investing time or money in its production) and the readership.
Many large print publishers now provide digital reproduction of their print magazine titles through various online services for a fee. These service providers also refer to their collections of these digital format products as online magazines, and sometimes as digital magazines.
Online magazines representing matters of interest to specialists or societies for academic subjects, science, trade, or industry are typically referred to as online journals.
Business model
Many general interest online magazines provide free access to all aspects of their online content, although some publishers have opted to require a subscription fee to access premium online article and/or multimedia content. Online magazi
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https://en.wikipedia.org/wiki/Sigma%20electron%20donor-acceptor
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The sEDA parameter (sigma electron donor-acceptor) is a sigma-electron substituent effect scale, described also as inductive and electronegativity related effect. There is also a complementary scale - pEDA. The more positive is the value of sEDA the more sigma-electron donating is a substituent. The more negative sEDA, the more sigma-electron withdrawing is the substituent (see the table below).
The sEDA parameter for a given substituent is calculated by means of quantum chemistry methods. The model molecule is the monosubstituted benzene. First the geometry should be optimized at a suitable model of theory, then the natural population analysis within the framework of Natural Bond Orbital theory is performed. The molecule have to be oriented in such a way that the aromatic benzene ring lays in the xy plane and is perpendicular to the z-axis. Then, the 2s, 2px and 2py orbital occupations of ring carbon atoms are summed up to give the total sigma system occupation. From this value the sum of sigma-occupation for unsubstituted benzene is subtracted resulting in original sEDA parameter. For sigma-electron donating substituents like -Li, -BH2, -SiH3, the sEDA parameter is positive, and for sigma-electron withdrawing substituents like -F, -OH, -NH2, -NO2, -COOH the sEDA is negative.
The sEDA scale was invented by Wojciech P. Oziminski and Jan Cz. Dobrowolski and the details are available in the original paper.
The sEDA scale linearly correlates with experimental substituent constants like Taft-Topsom σR parameter.
For easy calculation of sEDA the free of charge for academic purposes written in Tcl program with Graphical User Interface AromaTcl is available.
Sums of sigma-electron occupations and sEDA parameter for substituents of various character are gathered in the following table:
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https://en.wikipedia.org/wiki/Discovery%20and%20Launch
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Discovery and Launch (DIAL) is a protocol co-developed by Netflix and YouTube with help from Sony and Samsung. It is a mechanism for discovering and launching applications on a single subnet, typically a home network. It relies on Universal Plug and Play (UPnP), Simple Service Discovery Protocol (SSDP), and HTTP protocols. The protocol works without requiring a pairing between devices. It was formerly used by the Chromecast media streaming adapter that was introduced in July 2013 by Google. (Chromecast now uses mDNS instead of DIAL.) DIAL enables what the TV industry calls second screen devices, such as tablet computers and mobile phones to send content to first screen devices, such as televisions, Blu-ray players, and set-top boxes.
Terminology and operation
1st screen: a television, Blu-ray player, set-top-box, or similar device.
2nd screen: a smartphone, tablet, or similar device.
DIAL Server: a device implementing the server side of the DIAL protocol, usually a 1st screen device.
DIAL Client: a device that can discover and launch applications on a DIAL server – usually a 2nd screen device.
The DIAL protocol has two components, DIAL Service Discovery and the DIAL REST Service. The DIAL Service Discovery enables a DIAL client device to discover DIAL servers on its local network segment and obtain access to the DIAL REST Service on those devices. The DIAL REST Service enables a DIAL client to query, launch and optionally stop applications on a DIAL Server device.
See also
AirPlay
Digital Living Network Alliance (DLNA)
Jini
Miracast
Neighbor Discovery Protocol
Service Location Protocol
Simple Service Discovery Protocol
Zero-configuration networking
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https://en.wikipedia.org/wiki/Code%20page
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In computing, a code page is a character encoding and as such it is a specific association of a set of printable characters and control characters with unique numbers. Typically each number represents the binary value in a single byte. (In some contexts these terms are used more precisely; see .)
The term "code page" originated from IBM's EBCDIC-based mainframe systems, but Microsoft, SAP, and Oracle Corporation are among the vendors that use this term. The majority of vendors identify their own character sets by a name. In the case when there is a plethora of character sets (like in IBM), identifying character sets through a number is a convenient way to distinguish them. Originally, the code page numbers referred to the page numbers in the IBM standard character set manual, a condition which has not held for a long time. Vendors that use a code page system allocate their own code page number to a character encoding, even if it is better known by another name; for example, UTF-8 has been assigned page numbers 1208 at IBM, 65001 at Microsoft, and 4110 at SAP.
Hewlett-Packard uses a similar concept in its HP-UX operating system and its Printer Command Language (PCL) protocol for printers (either for HP printers or not). The terminology, however, is different: What others call a character set, HP calls a symbol set, and what IBM or Microsoft call a code page, HP calls a symbol set code. HP developed a series of symbol sets, each with an associated symbol set code, to encode both its own character sets and other vendors’ character sets.
The multitude of character sets leads many vendors to recommend Unicode.
The code page numbering system
IBM introduced the concept of systematically assigning a small, but globally unique, 16 bit number to each character encoding that a computer system or collection of computer systems might encounter. The IBM origin of the numbering scheme is reflected in the fact that the smallest (first) numbers are assigned to variations of IBM
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https://en.wikipedia.org/wiki/Actin%20assembly-inducing%20protein
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The Actin assembly-inducing protein (ActA) is a protein encoded and used by Listeria monocytogenes to propel itself through a mammalian host cell. ActA is a bacterial surface protein comprising a membrane-spanning region. In a mammalian cell the bacterial ActA interacts with the Arp2/3 complex and actin monomers to induce actin polymerization on the bacterial surface generating an actin comet tail. The gene encoding ActA is named actA or prtB.
Introduction
As soon as L. monocytogenes bacteria are ingested by humans, they get internalized into intestinal epithelium cells and rapidly try to escape their internalization vacuole. In the cytosol they start to polymerize actin on their surface by the help of the ActA protein. It has been shown that ActA is not only necessary but also sufficient to induce motility of bacteria in the absence of other bacterial factors.
Discovery
ActA was discovered by analysing lecithinase-negative Tn917-lac Listeria mutants because of the phenotype that they were unable to spread from cell to cell. These mutant bacteria still escaped from the phagosomes as efficiently as wild-type bacteria and multiplied within the infected cells but they were not surrounded by actin like wild-type bacteria. Further analysis showed, that Tn917-lac had inserted into actA, the second gene of an operon. The third gene of this operon, plcB, encodes the L. monocytogenes lecithinase. To determine whether actA itself, plcB or other co-transcribed downstream regions are involved in actin assembly, mutations in the appropriate genes were generated. All mutants except the actA mutants were similar to wild-type concerning association with F-actin and cell-cell spreading. Complementation with actA restored wild-type phenotype in the actA mutants.
Function
ActA is a protein which acts as a mimic of Wiskott-Aldrich syndrome protein (WASP), a nucleation promoting factor (NPF) present in host cells. NPFs in the mammalian cell recruit and bind to the already existin
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https://en.wikipedia.org/wiki/List%20of%20national%20liquors
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This is a list of national liquors. A national liquor is a distilled alcoholic beverage considered standard and respected in a given country. While the status of many such drinks may be informal, there is usually a consensus in a given country that a specific drink has national status or is the "most popular liquor" in a given nation. This list is distinct from national drink, which include non-alcoholic beverages.
East Asia
: Baijiu (including Kaoliang liquor) (sorghum, rice, wheat, barley, millet)
: Kaoliang liquor
: Sake, Shōchū (including Awamori) (rice, barley, sweet potatoes, buckwheat), Japanese whisky
: Pyongyang Soju
: Soju (rice, barley, corn, potato, sweet potato)
: Kumis (Airag)
Europe
: Rakia
: Inländer Rum & schnapps (fruit)
: Krambambula
: Jenever (malt and Juniper)
: Rakija (fruit: apples, plums, pears)
: Rakia (grapes, apricots, plums)
: Rakija (fruit: plums, pears) and Pelinkovac
: Zivania (wine or grape residue left over from winemaking) and Commandaria (sweet dessert wine)
: Becherovka (herbs) or Slivovice (plums)
: Akvavit (grain or potatoes)
: Vana Tallinn
: Koskenkorva Viina (grain (barley) and Finlandia vodka (barley)
: Calvados (apple brandy from Normandy); Armagnac and Cognac, Pastis
: Schnapps (fruit) (in the South), Korn (in the North)
: Raki (Ρακί ή Ρακή), produced from fruit. Ouzo (distilled 96 percent pure ethyl alcohol and Anise). Crete: Tsikoudia (pomace raki). Mainland Greece: Tsipouro (pomace raki)
: Unicum (herbs), Pálinka (fruit), Tokaji
: Brennivín, aka “Black Death” (potatoes)
: Irish Whiskey (fermented mash of cereal grains), Poitín (malted barley grain)
: Grappa (pomace and grape residue left over from winemaking), Limoncello, Amaretto, Amaro, Fernet, Mirto, Alchermes, Aperol, Campari, Cynar, Frangelico, Maraschino, Rosolio, Sambuca, Strega
: Riga Black Balsam
: Midus
: Rakija and Mastika (Typically, red and/or white grapes. Plums used in some areas such as Kichevo. Mastika is anise and herb fl
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https://en.wikipedia.org/wiki/Super%20Hydlide
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Super Hydlide is an action role-playing game for the Sega Genesis/Mega Drive. It was originally released in 1987 in Japan only under the title for the MSX, MSX2, and PC-8801mkII SR. It's the third game in the Hydlide series. Ports were also released for the X1, Famicom, X68000, and Microsoft Windows. The game was developed by Hydlide series veterans T&E Soft and released worldwide on the Sega Genesis / Mega Drive on October 6, 1989, in Japan, early 1990 in the United States, and 1991 in Europe. This remake evidences substantial graphical upgrades to the original Hydlide 3, though the gameplay remains largely identical. Before its release, it was called Hollo Fighter in some Sega advertising material and was one of the first third party published titles to be released in the U.S, the other being Air Diver.
Story
Many years after the events of Hydlide II, an explosion of flames appeared near The City of the Woods. After that, monsters spread throughout the world. A young man is chosen to find the source of the evil.
Gameplay
The game incorporates a 'good/evil character' morality/alignment system. Like its predecessor Hydlide II: Shine of Darkness (1985), the player has a morality meter that can be aligned with either Justice, Normal, or Evil. The game has both good and evil monsters. Evil monsters attack the player character on sight, while good monsters only attack if the player character attacks them first. Killing any monster, good or evil, results in a reward of experience points, money, and occasionally a piece of equipment. However, if the player kills a good monster, points are lost from a statistic called "MF" (Moral Fiber). If the player's MF stat drops to zero, frequent traps will appear across the world. If the player manages to keep it over 100, rewards appear in the form of random items found around Fairyland. Unlike Hydlide II, the morality meter no longer affects the way in which the townsfolk react to the player.
The game also features an in-game c
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https://en.wikipedia.org/wiki/Descent%20%28video%20game%29
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Descent is a first-person shooter (FPS) game developed by Parallax Software and released by Interplay Productions in 1995 for MS-DOS, and later for Macintosh, PlayStation, and RISC OS. It popularized a subgenre of FPS games employing six degrees of freedom and was the first FPS to feature entirely true-3D graphics. The player is cast as a mercenary hired to eliminate the threat of a mysterious extraterrestrial computer virus infecting off-world mining robots. In a series of mines throughout the Solar System, the protagonist pilots a spaceship and must locate and destroy the mine's power reactor and escape before being caught in the mine's self-destruction, defeating opposing robots along the way. Players can play online and compete in either deathmatches or cooperate to take on the robots.
Descent was a commercial success. Together with its sequel, it sold over 1.1 million units as of 1998 and was critically acclaimed. Commentators and reviewers compared it to Doom and praised its unrestrained range of motion and full 3D graphics. The combination of traditional first-person shooter mechanics with that of a space flight simulator was also well received. Complaints tended to focus on the frequency for the player to become disoriented and the potential to induce motion sickness. The game's success spawned expansion packs and the sequels Descent II (1996) and Descent 3 (1999).
Gameplay
Single-player
Descent is a first-person shooter and shoot 'em up game wherein the player pilots a spaceship through labyrinthine mines while fighting virus-infected robots, using the ship's armaments. They must find and destroy each mine's reactor core, triggering a meltdown that will destroy the mine as the player escapes. For two levels, the reactor core is replaced with a boss. To obtain access to the reactor, the player must collect one or a combination of the three colored access keys for each level. As a secondary objective, the player can also choose to rescue PTMC (Post Terran
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https://en.wikipedia.org/wiki/University%20Library%2C%20Bratislava
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University Library in Bratislava (ULB) is the oldest library in Slovakia. It was founded in 1919 in Bratislava. Today, it is the largest and most visited library in Slovakia and it is a universal state research library.
History
The library was one of the first cultural and educational institutions set up in the newly founded Czecho-Slovak Republic after WWI at the territory of Slovakia to support the emerging university education, science and library system. Its origin in 1919 was closely connected with the newly founded Comenius Czecholslovak State University where the name of the university was reflected in the Library's name. The library has never become an integral part of university, although relations between the two institutions were based on collaboration and close contact. The Library keeps its name because it refers to the original close contact towards the university and at the same time reflects the universal character of its collections.
As the time passed by the authorities set further goals and competences for ULB within the national and international framework. ULB has become the first library entitled to the legal deposit from the territory of Slovakia, and it is the only one which has kept this tradition since 1919 until today. Library's historical book collections also have the character of a depository collection. Until 1954 ULB fulfilled the tasks of the national library in Slovakia. Since then it has the statute of a universal state research library.
Throughout its history two clear directions can be identified : a solid leading place in the national library system and active participation in international library cooperation.
Reconstruction of the historical buildings of the Library
The main objective was to renew buildings which are protected as cultural monuments, to modernize decaying library premises, to solve the lack of stacks and eliminated the danger of stagnation in the field of library services. Realization of the investment proj
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https://en.wikipedia.org/wiki/UNI/O
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The UNI/O bus is an asynchronous serial bus created by Microchip Technology for low speed communication in embedded systems. The bus uses a master/slave configuration, requiring one signal to pass data between devices. The first devices supporting the UNI/O bus were released in May 2008.
Interface
The UNI/O bus requires one logic signal:
SCIO — Serial Clock, Data Input/Output
Only one master device is allowed per bus, but multiple slave devices can be connected to a single UNI/O bus. Individual slaves are selected through an 8-bit to 12-bit address included in the command overhead.
Both master and slave devices use a tri-stateable, push-pull I/O pin to connect to SCIO, with the pin being placed in a high impedance state when not driving the bus. Because push-pull outputs are used, the output driver on slave devices is current-limited to prevent high system currents from occurring during bus collisions.
The idle state of the UNI/O bus is logic high. A pull-up resistor can be used to ensure the bus remains idle when no device is driving SCIO, but is not required for operation.
Data encoding
Bit encoding
Clock and data signals are combined and communicated on the bus through Manchester encoding. This means that each data bit is transmitted in a fixed amount of time (called the "bit period").
The UNI/O specification places certain rules on the bit period:
It is determined by the master.
Slaves are required to synchronize with the master to recover the bit period during the start header.
It can be within 10 µs and 100 µs (corresponding to a bit rate of 100 kbit/s to 10 kbit/s, respectively).
It is only required to be fixed within a single bus operation (for new bus operations, the master can choose a different bit period).
In accordance with Manchester encoding, the bit value is defined by a signal transition in the middle of the bit period. UNI/O uses the IEEE 802.3 convention for defining 0 and 1 values:
A high-to-low transition signifies a 0.
A
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https://en.wikipedia.org/wiki/Flag%20of%20Arkansas
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The flag of Arkansas, also known as the Arkansas flag, consists of a red field charged with a large blue-bordered white lozenge (diamond). Twenty-nine five-pointed stars appear on the flag: twenty-five small white stars within the blue border, and four larger blue stars in the white diamond. The inscription "ARKANSAS" appears in blue within the white lozenge, with one star above and three stars below. The star above and the two outer stars below point upwards; the inner star below points downwards. The flag was designed by Willie K. Hocker of Wabbaseka, a member of Pine Bluff Chapter of the Arkansas Society of the Daughters of the American Revolution.
History
In 1912, the Pine Bluff Chapter of the Daughters of the American Revolution decided to present the newly commissioned battleship USS Arkansas with an official state flag. The chapter contacted Arkansas secretary of state Earle E. Hodges requesting information on how to obtain the state's flag. Hodges then informed the chapter that in fact no such state flag existed. With Hodge's support, the Pine Bluff Chapter began a statewide contest to design a new state flag. A committee was appointed, and it asked for designs to be submitted for consideration. Hocker's design was "a rectangular field of red, on which is placed a large white diamond, bordered by a wide band of blue. Across the diamond is the word 'ARKANSAS'," (placed there by request of the committee) "and the blue stars, one above, two below the word. On the blue band are placed 25 white stars." This flag was adopted by the Arkansas legislature on February 26, 1913.
In 1923, the legislature added a fourth star, representing the Confederate States. This fourth star was originally placed so that there were two stars above the state name and two below; this was to include the Confederate States alongside France, Spain, and the United States. Since this disturbed the other two meanings of the original three stars, the legislature corrected this in 1924 by p
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https://en.wikipedia.org/wiki/Sine%20wave
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A sine wave, sinusoidal wave, or sinusoid (symbol: ∿) is a periodic wave whose waveform (shape) is the trigonometric sine function.
In mechanics, as a linear motion over time, this is simple harmonic motion; as rotation, it corresponds to uniform circular motion.
Sine waves occur often in physics, including wind waves, sound waves, and light waves.
In engineering, signal processing, and mathematics, Fourier analysis decomposes general functions into a sum of sine waves of various frequencies.
When any two sine waves of the same frequency (but arbitrary phase) are linearly combined, the result is another sine wave of the same frequency; this property is unique among periodic waves. Conversely, if some phase is chosen as a zero reference, a sine wave of arbitrary phase can be written as the linear combination of two sine waves with phases of zero and a quarter cycle, the sine and cosine components, respectively. (In this context it can be helpful to call waves of arbitrary phase sinusoids, to avoid confusion.)
Audio example
A sine wave represents a single frequency with no harmonics and is considered an acoustically pure tone. Adding sine waves of different frequencies results in a different waveform. Presence of higher harmonics in addition to the fundamental causes variation in the timbre, which is the reason why the same musical pitch played on different instruments sounds different.
Sine wave as a function of time
Sine waves that are only a function of time can be represented by the form:
where:
, amplitude, the peak deviation of the function from zero.
, ordinary frequency, the number of oscillations (cycles) that occur each second of time.
, angular frequency, the rate of change of the function argument in units of radians per second.
, phase, specifies (in radians) where in its cycle the oscillation is at t = 0.
When is non-zero, the entire waveform appears to be shifted backwards in time by the amount seconds. A negative value represents a delay
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https://en.wikipedia.org/wiki/E48%20particulate%20bomb
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The E48 particulate bomb was a U.S. biological sub-munition designed during the 1950s for use with the E96 cluster bomb.
History
In February 1950 a U.S. Army report prepared by William Creasy, a colonel within the U.S. bio-weapons program, noted that the E48 particulate bomb was in its final stages of development. Creasy also reported that the E48 had been successfully tested in three field trials.
Specifications
The E48 particulate bomb was a sub-munition meant to be clustered in the E38 type cluster adapter, together the E48 and E38 constituted the E96 cluster bomb. In practice, the E96 and its payload of E48 sub-munitions was intended to be air-dropped from . The weapon could generate an elliptical aerosol agent cloud from this altitude that had major axes of . Some of the agents considered for use with the E48 included, B. suis, anthrax, and botulin.
Tests involving the E48
The E48 sub-munition was utilized in tests at Dugway Proving Ground in July and August 1950. The July tests released Bacillus globigii from the E48 using air-dropped cluster bombs. The August tests utilized the bacteria Serratia marcescens, and involved E48s which dispersed the agent statically, from the ground.
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https://en.wikipedia.org/wiki/Appeal%20to%20tradition
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Appeal to tradition (also known as argumentum ad antiquitatem or argumentum ad antiquitam, appeal to antiquity, or appeal to common practice) is a claim in which a thesis is deemed correct on the basis of correlation with past or present tradition. The appeal takes the form of "this is right because we've always done it this way", and is a logical fallacy. The opposite of an appeal to tradition is an appeal to novelty, in which one claims that an idea is superior just because it is new.
An appeal to tradition essentially makes two assumptions that may not be necessarily true:
The old way of thinking was proven correct when introduced, i.e. since the old way of thinking was prevalent, it was necessarily correct.
In reality, this may be false—the tradition might be entirely based on incorrect grounds.
The past justifications for the tradition are still valid.
In reality, the circumstances may have changed; this assumption may also therefore have become untrue.
See also
Appeal to novelty
Argument from authority
Argument to moderation
Common sense
Conservatism
Herd mentality
Inductive reasoning
List of logical fallacies
Precedent
Social inertia
Status quo
Notes
Tradition
Conservatism
Genetic fallacies
Fallacies
Tradition
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https://en.wikipedia.org/wiki/Cracovian
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In astronomical and geodetic calculations, Cracovians are a clerical convenience introduced in the 1930s by Tadeusz Banachiewicz for solving systems of linear equations by hand. Such systems can be written as in matrix notation where x and b are column vectors and the evaluation of b requires the multiplication of the rows of A by the vector x.
Cracovians introduced the idea of using the transpose of A, AT, and multiplying the columns of AT by the column x. This amounts to the definition of a new type of matrix multiplication denoted here by '∧'. Thus . The Cracovian product of two matrices, say A and B, is defined by , where BT and A are assumed compatible for the common (Cayley) type of matrix multiplication.
Since , the products and will generally be different; thus, Cracovian multiplication is non-associative. Cracovians are an example of a quasigroup.
Cracovians adopted a column-row convention for designating individual elements as opposed to the standard row-column convention of matrix analysis. This made manual multiplication easier, as one needed to follow two parallel columns (instead of a vertical column and a horizontal row in the matrix notation.) It also sped up computer calculations, because both factors' elements were used in a similar order, which was more compatible with the sequential access memory in computers of those times — mostly magnetic tape memory and drum memory. Use of Cracovians in astronomy faded as computers with bigger random access memory came into general use. Any modern reference to them is in connection with their non-associative multiplication.
In programming
In R the desired effect can be achieved via the crossprod() function. Specifically, the Cracovian product of matrices A and B can be obtained as crossprod(B, A).
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https://en.wikipedia.org/wiki/Cognition
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Cognition is the "mental action or process of acquiring knowledge and understanding through thought, experience, and the senses". It encompasses all aspects of intellectual functions and processes such as: perception, attention, thought, imagination, intelligence, the formation of knowledge, memory and working memory, judgment and evaluation, reasoning and computation, problem-solving and decision-making, comprehension and production of language. Cognitive processes use existing knowledge and discover new knowledge.
Cognitive processes are analyzed from different perspectives within different contexts, notably in the fields of linguistics, musicology, anesthesia, neuroscience, psychiatry, psychology, education, philosophy, anthropology, biology, systemics, logic, and computer science. These and other approaches to the analysis of cognition (such as embodied cognition) are synthesized in the developing field of cognitive science, a progressively autonomous academic discipline.
Etymology
The word cognition dates back to the 15th century, where it meant "thinking and awareness". The term comes from the Latin noun ('examination', 'learning', or 'knowledge'), derived from the verb , a compound of ('with') and ('know'). The latter half, , itself is a cognate of a Greek verb, ().
Early studies
Despite the word cognitive itself dating back to the 15th century, attention to cognitive processes came about more than eighteen centuries earlier, beginning with Aristotle (384–322 BC) and his interest in the inner workings of the mind and how they affect the human experience. Aristotle focused on cognitive areas pertaining to memory, perception, and mental imagery. He placed great importance on ensuring that his studies were based on empirical evidence, that is, scientific information that is gathered through observation and conscientious experimentation. Two millennia later, the groundwork for modern concepts of cognition was laid during the Enlightenment by thinkers suc
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https://en.wikipedia.org/wiki/1729%20%28number%29
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1729 is the natural number following 1728 and preceding 1730. It is notably the first taxicab number.
In mathematics
1729 is the smallest taxicab number, and is variously known as Ramanujan's number or the Ramanujan–Hardy number, after an anecdote of the British mathematician G. H. Hardy when he visited Indian mathematician Srinivasa Ramanujan in hospital. He related their conversation:
The two different ways are:
1729 = 13 + 123 = 93 + 103
The quotation is sometimes expressed using the term "positive cubes", since allowing negative perfect cubes (the cube of a negative integer) gives the smallest solution as 91 (which is a divisor of 1729; 1991 = 1729).
91 = 63 + (−5)3 = 43 + 33
1729 was also found in one of Ramanujan's notebooks dated years before the incident, and was noted by Frénicle de Bessy in 1657. A commemorative plaque now appears at the site of the Ramanujan-Hardy incident, at 2 Colinette Road in Putney.
The same expression defines 1729 as the first in the sequence of "Fermat near misses" defined, in reference to Fermat's Last Theorem, as numbers of the form which are also expressible as the sum of two other cubes .
Other properties
1729 is a sphenic number. It is the third Carmichael number, the first Chernick–Carmichael number , the first absolute Euler pseudoprime, and the third Zeisel number. It is a centered cube number, as well as a dodecagonal number, a 24-gonal and 84-gonal number.
Investigating pairs of distinct integer-valued quadratic forms that represent every integer the same number of times, Schiemann found that such quadratic forms must be in four or more variables, and the least possible discriminant of a four-variable pair is 1729.
1729 is the lowest number which can be represented by a Loeschian quadratic form in four different ways with a and b positive integers. The integer pairs are (25,23), (32,15), (37,8) and (40,3).
1729 is also the smallest integer side of an equilateral triangle for which there are three sets o
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https://en.wikipedia.org/wiki/Clinophilia
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In medicine, clinophilia is a sleep disorder described as the tendency of a patient to remain in bed in a reclined position without sleeping for prolonged periods of time.
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https://en.wikipedia.org/wiki/Generic%20function
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In computer programming, a generic function is a function defined for polymorphism.
In statically typed languages
In statically typed languages (such as C++ and Java), the term generic functions refers to a mechanism for compile-time polymorphism (static dispatch), specifically parametric polymorphism. These are functions defined with TypeParameters, intended to be resolved with compile time type information. The compiler uses these types to instantiate suitable versions, resolving any function overloading appropriately.
In Common Lisp Object System
In some systems for object-oriented programming such as the Common Lisp Object System (CLOS) and Dylan, a generic function is an entity made up of all methods having the same name. Typically a generic function is an instance of a class that inherits both from function and standard-object. Thus generic functions are both functions (that can be called with and applied to arguments) and ordinary objects. The book The Art of the Metaobject Protocol explains the implementation and use of CLOS generic functions in detail.
One of the early object-oriented programming extensions to Lisp is Flavors. It used the usual message sending paradigm influenced by Smalltalk. The Flavors syntax to send a message is:
(send object :message)
With New Flavors, it was decided the message should be a real function and the usual function calling syntax should be used:
(message object)
message now is a generic function, an object and function in its own right. Individual implementations of the message are called methods.
The same idea was implemented in CommonLoops. New Flavors and CommonLoops were the main influence for the Common Lisp Object System.
Example
Common Lisp
Define a generic function with two parameters object-1 and object-2. The name of the generic function is collide.
(defgeneric collide (object-1 object-2))
Methods belonging to the generic function are defined outside of classes.
Here we define a method for the gen
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https://en.wikipedia.org/wiki/Julian%20Schwinger
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Julian Seymour Schwinger (; February 12, 1918 – July 16, 1994) was a Nobel Prize-winning American theoretical physicist. He is best known for his work on quantum electrodynamics (QED), in particular for developing a relativistically invariant perturbation theory, and for renormalizing QED to one loop order. Schwinger was a physics professor at several universities.
Schwinger is recognized as one of the greatest physicists of the twentieth century, responsible for much of modern quantum field theory, including a variational approach, and the equations of motion for quantum fields. He developed the first electroweak model, and the first example of confinement in 1+1 dimensions. He is responsible for the theory of multiple neutrinos, Schwinger terms, and the theory of the spin-3/2 field.
Biography
Early life and career
Julian Seymour Schwinger was born in New York City, to Ashkenazi Jewish parents, Belle (née Rosenfeld) and Benjamin Schwinger, a garment manufacturer, who had emigrated from Poland to the United States. Both his father and his mother's parents were prosperous clothing manufacturers, although the family business declined after the Wall Street Crash of 1929. The family followed the Orthodox Jewish tradition. Julian's older brother Harold Schwinger was born in 1911, seven years before Julian who was born in 1918.
Schwinger was a precocious student. He attended the Townsend Harris High School from 1932 to 1934, a highly regarded high school for gifted students at the time. During high school, Julian had already started reading Physical Review papers by authors such as Paul Dirac in the library of the City College of New York, in whose campus Townsend Harris was then located.
In the fall of 1934, Schwinger entered the City College of New York as an undergraduate. CCNY automatically accepted all Townsend Harris graduates at the time, and both institutions offered free tuition. Due to his intense interest in physics and mathematics, Julian performed very w
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https://en.wikipedia.org/wiki/Center%20for%20Quantum%20Spintronics
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The Center for Quantum Spintronics (QuSpin) is a research center at the Department of Physics at the Norwegian University of Science and Technology (NTNU).
In 2017, the Research Council of Norway designated QuSpin as a Center of Excellence (SFF) for the period 2017–2027.
Spintronics, or spin electronics, is a field in condensed matter physics, a study of the physical effects associated with quantum mechanical spin. Electrons do not only have charge. They also have a spin, an apparent inner rotation, as if the electrons spin around their own axis. Spintronics has already contributed to a revolution in data storage, and was, among other things, the basis for Apple's music player iPod.
The researchers at QuSpin aim to describe and develop new ways of controlling electrical signals. This may contribute to a major development in energy efficient information and communication technology. The results of their research have already attracted interest internationally, and have been discussed and published in several scientific journals, e.g. Nature and Science.
In electronics, the electrical charge of electrons is used to store and process information. Electric currents generate a lot of heat, which is emitted to the surroundings. This is an increasing challenge, and limits how small and efficient electronic devices can be.
QuSpin works to find new ways of controlling and utilizing electrons' intrinsic spin. The goal is to control the spin, and other quantum mechanical variables, using new combinations of nanoscale materials. Their research includes studies of quantum mechanical transport properties for superconducting, magnetic and topological materials.
QuSpin has research activity in both theoretical and experimental physics. By the end of 2018, the center had a team of more than 60 members, of which 11 were professors and associate professors; three researchers; seven postdocs and 26 Ph.D. students.
The center management consists (as of 2020) of four primary
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https://en.wikipedia.org/wiki/FOXP2
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Forkhead box protein P2 (FOXP2) is a protein that, in humans, is encoded by the FOXP2 gene. FOXP2 is a member of the forkhead box family of transcription factors, proteins that regulate gene expression by binding to DNA. It is expressed in the brain, heart, lungs and digestive system.
FOXP2 is found in many vertebrates, where it plays an important role in mimicry in birds (such as birdsong) and echolocation in bats. FOXP2 is also required for the proper development of speech and language in humans. In humans, mutations in FOXP2 cause the severe speech and language disorder developmental verbal dyspraxia. Studies of the gene in mice and songbirds indicate that it is necessary for vocal imitation and the related motor learning. Outside the brain, FOXP2 has also been implicated in development of other tissues such as the lung and digestive system.
Initially identified in 1998 as the genetic cause of a speech disorder in a British family designated the KE family, FOXP2 was the first gene discovered to be associated with speech and language and was subsequently dubbed "the language gene". However, other genes are necessary for human language development, and a 2018 analysis confirmed that there was no evidence of recent positive evolutionary selection of FOXP2 in humans.
Structure and function
As a FOX protein, FOXP2 contains a forkhead-box domain. In addition, it contains a polyglutamine tract, a zinc finger and a leucine zipper. The protein attaches to the DNA of other proteins and controls their activity through the forkhead-box domain. Only a few targeted genes have been identified, however researchers believe that there could be up to hundreds of other genes targeted by the FOXP2 gene. The forkhead box P2 protein is active in the brain and other tissues before and after birth, many studies show that it is paramount for the growth of nerve cells and transmission between them. The FOXP2 gene is also involved in synaptic plasticity, making it imperative for learni
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https://en.wikipedia.org/wiki/JOHNNIAC
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The JOHNNIAC was an early computer built by the RAND Corporation (not Remington Rand, maker of the contemporaneous UNIVAC I computer) and based on the von Neumann architecture that had been pioneered on the IAS machine. It was named in honor of von Neumann, short for John von Neumann Numerical Integrator and Automatic Computer. JOHNNIAC is arguably the longest operational early computer, being used almost continuously from 1953 for over 13 years before finally being shut down on February 11, 1966, logging over 50,000 operating hours.
After being rescued from the scrap heap twice, the machine is currently at the Computer History Museum in Mountain View, California.
Like the IAS machine, JOHNNIAC used 40-bit words, and included 1024 words of Selectron tube main memory, each holding 256 bits of data. Two instructions were stored in every word in 20-bit subwords consisting of an 8-bit instruction and a 12-bit address, the instructions being operated in series with the left subword running first. The initial machine had 83 instructions. A single register, named A, supplied an accumulator and the machine also featured a register named Q, for quotient. There was only one test condition, whether or not the high bit of the A register was set. There were no index registers, and as addresses were stored in the instructions, loops had to be implemented by modifying the instructions as the program ran. Since the machine only had 10 bits of address space, two of the address bits were unused and were sometimes used for data storage by interleaving data through the instructions.
JOHNNIAC weighed .
Numerous modifications were made to the system over its lifetime. In March 1955, 4096 words of magnetic-core memory were added to the system, replacing the earlier Selectrons. This required all 12 bits of addressing, and caused programs that stored data in the "spare bits" to fail. Later in 1955 a 12k-word drum memory secondary storage system was added as well. A transistor-based adde
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https://en.wikipedia.org/wiki/Solemoviridae
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Solemoviridae is a family of non-enveloped, positive-strand RNA viruses which infect plants. Solemoviridae is a member of the order Sobelivirales.
Structure
Member viruses are non-enveloped and have a viral capsid with T=3 symmetry.
Genome
Solemoviruses have a positive-sense, single-strand RNA genome. The length of the genome is 4652 bp. The 3' terminus does not have a polyA-tail. The 5' terminus has a genome-linked viral protein (VPg).
Taxonomy
The family contains four genera and seven species unassigned to a genus:
Genera:
Enamovirus
Polemovirus
Polerovirus
Sobemovirus
Species unassigned to a genus:
Barley yellow dwarf virus GPV
Barley yellow dwarf virus SGV
Chickpea stunt disease associated virus
Groundnut rosette assistor virus
Indonesian soybean dwarf virus
Sweet potato leaf speckling virus
Tobacco necrotic dwarf virus
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https://en.wikipedia.org/wiki/Protein%20engineering
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Protein engineering is the process of developing useful or valuable proteins through the design and production of unnatural polypeptides, often by altering amino acid sequences found in nature. It is a young discipline, with much research taking place into the understanding of protein folding and recognition for protein design principles. It has been used to improve the function of many enzymes for industrial catalysis. It is also a product and services market, with an estimated value of $168 billion by 2017.
There are two general strategies for protein engineering: rational protein design and directed evolution. These methods are not mutually exclusive; researchers will often apply both. In the future, more detailed knowledge of protein structure and function, and advances in high-throughput screening, may greatly expand the abilities of protein engineering. Eventually, even unnatural amino acids may be included, via newer methods, such as expanded genetic code, that allow encoding novel amino acids in genetic code.
Approaches
Rational design
In rational protein design, a scientist uses detailed knowledge of the structure and function of a protein to make desired changes. In general, this has the advantage of being inexpensive and technically easy, since site-directed mutagenesis methods are well-developed. However, its major drawback is that detailed structural knowledge of a protein is often unavailable, and, even when available, it can be very difficult to predict the effects of various mutations since structural information most often provide a static picture of a protein structure. However, programs such as Folding@home and Foldit have utilized crowdsourcing techniques in order to gain insight into the folding motifs of proteins.
Computational protein design algorithms seek to identify novel amino acid sequences that are low in energy when folded to the pre-specified target structure. While the sequence-conformation space that needs to be searched is
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https://en.wikipedia.org/wiki/Umbilical%20cord
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In placental mammals, the umbilical cord (also called the navel string, birth cord or funiculus umbilicalis) is a conduit between the developing embryo or fetus and the placenta. During prenatal development, the umbilical cord is physiologically and genetically part of the fetus and (in humans) normally contains two arteries (the umbilical arteries) and one vein (the umbilical vein), buried within Wharton's jelly. The umbilical vein supplies the fetus with oxygenated, nutrient-rich blood from the placenta. Conversely, the fetal heart pumps low-oxygen, nutrient-depleted blood through the umbilical arteries back to the placenta.
Structure and development
The umbilical cord develops from and contains remnants of the yolk sac and allantois. It forms by the fifth week of development, replacing the yolk sac as the source of nutrients for the embryo. The cord is not directly connected to the mother's circulatory system, but instead joins the placenta, which transfers materials to and from the maternal blood without allowing direct mixing. The length of the umbilical cord is approximately equal to the crown-rump length of the fetus throughout pregnancy. The umbilical cord in a full term neonate is usually about 50 centimeters (20 in) long and about 2 centimeters (0.75 in) in diameter. This diameter decreases rapidly within the placenta. The fully patent umbilical artery has two main layers: an outer layer consisting of circularly arranged smooth muscle cells and an inner layer which shows rather irregularly and loosely arranged cells embedded in abundant ground substance staining metachromatic. The smooth muscle cells of the layer are rather poorly differentiated, contain only a few tiny myofilaments and are thereby unlikely to contribute actively to the process of post-natal closure.
Umbilical cord can be detected on ultrasound by 6 weeks of gestation and well-visualised by 8 to 9 weeks of gestation.
The umbilical cord lining is a good source of mesenchymal and epith
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https://en.wikipedia.org/wiki/Hot-potato%20routing
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In commercial network routing between autonomous systems which are interconnected in multiple locations, hot-potato routing is the practice of passing traffic off to another autonomous system as quickly as possible, thus using their network for wide-area transit. Cold-potato routing is the opposite, where the originating autonomous system internally forwards the packet until it is as near to the destination as possible.
Behaviors
Hot-potato routing is the normal behavior of most settlement-free peering agreements. Hot-potato routing has the effect that the network receiving the data bears the cost of carrying it between cities. When the traffic ratio (the ratio of traffic flowing in one direction to the traffic flowing in the other direction between peers) is reasonably even, this is considered fair, because the networks will share evenly in carrying traffic exchanged by their customers between cities. The marginal cost of carrying traffic between cities depends on how the network has purchased those links; some networks own dark fiber, which can be upgraded by merely replacing the equipment on each end of the fiber, and possibly the amplifiers along the path between cities. In other cases, the network has an agreement with a telco that allows for a specific amount of bandwidth, and upgrading involves paying more money to the telco.
Cold-potato routing, on the other hand, is more expensive to do, but keeps the traffic under the network administrator's control for longer, allowing operators of well-provisioned networks to offer a higher quality of service to their customers. It can also be preferred when connecting to content providers; if content providers use cold-potato routing, they may escape from paying for the cost of links between cities. Cold-potato routing is prone to misconfiguration as well as poor coordination between two networks. In such scenarios, packets can be routed further distances and can allow another autonomous system to manipulate rout
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https://en.wikipedia.org/wiki/Lucas%20cell
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A Lucas cell is a type of scintillation counter. It is used to acquire a gas sample, filter out the radioactive particulates through a special filter and then count the radioactive decay. The inside of the gas chamber is coated with ZnS(Ag) - a chemical that emits light when struck by alpha particles. A photomultiplier tube at the top of the chamber counts the photons and sends the count to a data logger.
Radon measurement
A Lucas cell can be used to measure radon gas concentrations.
Radon itself is an inert gas. Its danger lies in the fact that it undergoes radioactive decay. The radon decay products may lodge in the lungs and bombard them with alpha and beta particles, thus increasing the risk of lung cancer.
See also
Geiger counter
Counting efficiency
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https://en.wikipedia.org/wiki/Fungible%20information
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Fungible information is the information for which the means of encoding is not important. Classical information theorists and computer scientists are mainly concerned with information of this sort.
It is sometimes referred as speakable information.
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https://en.wikipedia.org/wiki/Max-min%20fairness
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In communication networks, multiplexing and the division of scarce resources, max-min fairness is said to be achieved by an allocation if and only if the allocation is feasible and an attempt to increase the allocation of any participant necessarily results in the decrease in the allocation of some other participant with an equal or smaller allocation.
In best-effort statistical multiplexing, a first-come first-served (FCFS) scheduling policy is often used. The advantage with max-min fairness over FCFS is that it results in traffic shaping, meaning that an ill-behaved flow, consisting of large data packets or bursts of many packets, will only punish itself and not other flows. Network congestion is consequently to some extent avoided.
Fair queuing is an example of a max-min fair packet scheduling algorithm for statistical multiplexing and best-effort networks, since it gives scheduling priority to users that have achieved lowest data rate since they became active. In case of equally sized data packets, round-robin scheduling is max-min fair.
Comparison with other policies for resource sharing
Generally, policies for sharing resources that are characterized by low level of fairness (see fairness measures) provide high average throughput but low stability in the service quality, meaning that the achieved service quality is varying in time depending on the behavior of other users. If this instability is severe, it may result in unhappy users who will choose another more stable communication service.
Max-min fair resource sharing results in higher average throughput (or system spectral efficiency in wireless networks) and better utilization of the resources than a work-conserving equal sharing policy of the resources. In equal sharing, some dataflows may not be able to utilize their "fair share" of the resources. A policy for equal sharing would prevent a dataflow from obtaining more resources than any other flow, and from utilizing free resources in the network
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https://en.wikipedia.org/wiki/Riesz%20space
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In mathematics, a Riesz space, lattice-ordered vector space or vector lattice is a partially ordered vector space where the order structure is a lattice.
Riesz spaces are named after Frigyes Riesz who first defined them in his 1928 paper Sur la décomposition des opérations fonctionelles linéaires.
Riesz spaces have wide-ranging applications. They are important in measure theory, in that important results are special cases of results for Riesz spaces. For example, the Radon–Nikodym theorem follows as a special case of the Freudenthal spectral theorem. Riesz spaces have also seen application in mathematical economics through the work of Greek-American economist and mathematician Charalambos D. Aliprantis.
Definition
Preliminaries
If is an ordered vector space (which by definition is a vector space over the reals) and if is a subset of then an element is an upper bound (resp. lower bound) of if (resp. ) for all
An element in is the least upper bound or supremum (resp. greater lower bound or infimum) of if it is an upper bound (resp. a lower bound) of and if for any upper bound (resp. any lower bound) of (resp. ).
Definitions
Preordered vector lattice
A preordered vector lattice is a preordered vector space in which every pair of elements has a supremum.
More explicitly, a preordered vector lattice is vector space endowed with a preorder, such that for any :
Translation Invariance: implies
Positive Homogeneity: For any scalar implies
For any pair of vectors there exists a supremum (denoted ) in with respect to the order
The preorder, together with items 1 and 2, which make it "compatible with the vector space structure", make a preordered vector space.
Item 3 says that the preorder is a join semilattice.
Because the preorder is compatible with the vector space structure, one can show that any pair also have an infimum, making also a meet semilattice, hence a lattice.
A preordered vector space is a preordered vector lattice i
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https://en.wikipedia.org/wiki/1942%20Herefordshire%20TRE%20Halifax%20crash
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V9977 was an Handley Page Halifax II that had been sent to the Telecommunications Research Establishment (TRE) at RAF Defford to be used as a flying testbed for the H2S radar.
On the afternoon of 7 June 1942, one of its Rolls-Royce Merlin engines caught fire and led to the aircraft crashing near the England-Wales border, killing all eleven crew-members. Among the dead was Alan Blumlein of EMI, who was well known as the inventor of stereophonic sound recording and the 405-line television system used in the UK until 1985.
Investigators determined that improper engine maintenance/assembly procedures caused the accident. It remains the deadliest crash in the history of military test flight in the UK.
History
Construction
V9977 was an early model Halifax II, which introduced the more powerful Merlin XX engine and a number of other detail changes over the original model.
Chosen for H2S
At a meeting on 23 December 1941, the Secretary of State for Air, Archibald Sinclair, directed the TRE should direct their work on H2S radar towards the new four-engine bombers, Shorts Stirling, Handley Page Halifax and Avro Lancaster. Immediately thereafter, Philip Dee, B J O'Kane and Geoffrey Hensby visited the Aeroplane and Armament Experimental Establishment at Boscombe Down to examine the available aircraft and concluded that the Halifax had the best possibilities for mounting the scanner in different locations for testing.
On 1 January 1942, Bernard Lovell received orders from Albert Rowe, director of the TRE, to take over the direction of H2S. Three days later he visited Handley Page with Bob King, a TRE fitter who was well acquainted with the installation of test systems on a variety of aircraft, and Whitaker from Nash & Thompson, who were building the scanner system. They had collectively planned for the radar to be installed in a large long radome under the aircraft.
They were met at the factory by a team of high-ranking members of the Halifax design team, including the c
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https://en.wikipedia.org/wiki/Basophilic
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Basophilic is a technical term used by pathologists. It describes the appearance of cells, tissues and cellular structures as seen through the microscope after a histological section has been stained with a basic dye. The most common such dye is haematoxylin.
The name basophilic refers to the characteristic of these structures to be stained very well by basic dyes. This can be explained by their charges. Basic dyes are cationic, i.e. contain positive charges, and thus they stain anionic structures (i.e. structures containing negative charges), such as the phosphate backbone of DNA in the cell nucleus and ribosomes.
"Basophils" are cells that "love" (from greek "-phil") basic dyes, for example haematoxylin, azure and methylene blue. Specifically, this term refers to:
basophil granulocytes
anterior pituitary basophils
An abnormal increase in basophil granulocytes is therefore also described as basophilia.
The opposite of basophilic structures are acidophilic structures, also called eosinophilic. These structures contain many positive charges and are thus strongly stained by anionic dyes like eosin. A typical combination of basophilic and eosinophilic dyes is the H&E stain, which visualizes basophilic structures in blue and eosinophilic structures in red.
See also
Acidophile (histology)
Basophil cell
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https://en.wikipedia.org/wiki/Ara%20h%203
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Ara h 3 is a seed storage protein from Arachis hypogaea (peanuts). It is a heat stable 11S legumin-like globulin with a stable trimeric form that comprises 19% of the total protein in peanut extracts.
Structure
Ara h 3 forms homotrimers and has a highly stable structure, mediated through hydrophobic interactions. It has been established as an allergen.
The trimeric assemblies are stabilized by multiple hydrogen bonds.
Influence of Ara h 3 in peanut allergies
The protein Ara h 3 plays an important role in peanut allergic reactions. Ara h 3 makes up 19% of the total protein in peanut extracts and is classified as a major peanut allergen because it provokes sensitization of patients with this allergy.
This protein is a very potent allergen and it causes a severe reaction. The symptoms can be:
Skin reaction: urticarial, redness or edema.
Itchy reaction: usually around the mouth and throat.
Digestive problems: such as diarrhea, stomach cramps, nausea or vomiting.
Breath problems: it has a relation with the inflammation reaction which causes the blockage of the air passages.
Heart problems: histamine can cause a coronary artery spasm.
Anaphylaxis: a whole-body allergic reaction that causes low blood pressure, suffocation and can bring a person to death.
Treatment
No treatment is currently available, avoidance is the only option for peanut-allergic individuals. Unfortunately, consumers can be inadvertently exposed to peanut allergens when food becomes contaminated from processing lines shared with other peanut products. Therefore, there can be labelling mistakes because companies may not include peanuts as ingredients.
In consequence, therapeutic interventions and/or hypoallergenic peanuts are needed to prevent anaphylactic reactions caused by accidental ingestion of peanut-containing products by allergic individuals.
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https://en.wikipedia.org/wiki/Halomonadaceae
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Halomonadaceae is a family of halophilic Pseudomonadota.
History
The family was originally described in 1988 to contain the genera Halomonas and Deleya.
In 1989, Chromobacterium marismortui was reclassified as Chromohalobacter marismortui forming a third genus in the family Halomonadaceae.
Subsequently, in 1990 a species was discovered and was originally proposed to be called Volcaniella eurihalina forming a new genus in the Halomonadaceae, but was later (in 1995) reclassified as a member of the genus Halomonas.
The species Carnimonas nigrificans (sole member of genus) was not placed in the family due to the lack of two out of 15 descriptive 16S rRNA signature sequences, but it has been proposed to reclassify it into the family.
In 1996, the family was later reorganised by unifying genera Deleya, Halomonas and Halovibrio and the species Paracoccus halodenitrificans into Halomonas and placing Zymobacter in this family. However, it was later discovered that the strain of Halovibrio variabilis DSM 3051 and DSM 3050 differed and the latter was made type strain of the Halovibrio, which remains still in use. and now comprising two species (the other being Halovibrio denitrificans)
In 2002, Halomonas marina was transferred to its own genus Cobetia, and in 2009 Halomonas marisflavi, Halomonas indalinina. and Halomonas avicenniae were transferred to a new genus called Kushneria (5 species)
Several singleton genera were created recently: in 2007, Halotalea alkalilenta was described, Aidingimonas halophila in 2009, Halospina denitrificans in 2006, Modicisalibacter tunisiensis in 2009 Salinicola socius in 2009. To the latter genus two species were transferred Halomonas salaria as Salinicola salarius and Chromohalobacter salarius as Salinicola halophilus.
The family also contain the recently discovered but uncultured bacterium "Candidatus Portiera aleyrodidarum" (primary endosymbionts of whiteflies).
Genera
Halomonas, the type genus
Halomonas elongata, the type speci
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https://en.wikipedia.org/wiki/Patrick%20Dehornoy
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Patrick Dehornoy (11 September 1952 – 4 September 2019) was a mathematician at the University of Caen Normandy who worked on set theory and group theory.
Early life and education
Dehornoy was born on 11 September 1952 in Rouen, France. He graduated from the Lycée Pierre-Corneille in 1971. He studied at the École normale supérieure from 1971 to 1975 and completed his Ph.D. in 1978 at the University of Paris, with a thesis written under the direction of Kenneth Walter McAloon.
Career
Dehornoy was a researcher at the French National Centre for Scientific Research (CNRS) from 1975 to 1982. He was at the University of Caen Normandy as a Professor from 1983 to 2017 and as an Emeritus Professor from 2017 until his death. From 2009 to 2013, he was an adjunct scientific director of the (INSMI) at the CNRS. Dehornoy died on 4 September 2019 in Villejuif, France at the age of 66.
Research
Dehornoy found one of the first applications of large cardinals to algebra by constructing a certain left-invariant total order, called the Dehornoy order, on the braid group. In his later career, he was a major contributor to the theory of braid groups, including creating a fast algorithm for comparing braids, and was one of the main contributors to the development of Garside methods.
Awards
In 1999, Dehornoy received the Ferran Sunyer i Balaguer Prize. In 2002, he was elected a senior member of the Institut Universitaire de France (renewed in 2007). In 2005, he received the of the French Academy of Sciences. In 2014, he received the EMS Monograph Award for his book Foundations of Garside Theory.
Selected publications
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https://en.wikipedia.org/wiki/Music%20transposer
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A music transposer is a software program, physical or electronic device for the transposition of musical notes and/or chords from one note/key to another. It simply consists of two identical scales which can be moved in relation to each other to give the required result.
See also
List of music software
|
https://en.wikipedia.org/wiki/Rational%20dependence
|
In mathematics, a collection of real numbers is rationally independent if none of them can be written as a linear combination of the other numbers in the collection with rational coefficients. A collection of numbers which is not rationally independent is called rationally dependent. For instance we have the following example.
Because if we let , then .
Formal definition
The real numbers ω1, ω2, ... , ωn are said to be rationally dependent if there exist integers k1, k2, ... , kn, not all of which are zero, such that
If such integers do not exist, then the vectors are said to be rationally independent. This condition can be reformulated as follows: ω1, ω2, ... , ωn are rationally independent if the only n-tuple of integers k1, k2, ... , kn such that
is the trivial solution in which every ki is zero.
The real numbers form a vector space over the rational numbers, and this is equivalent to the usual definition of linear independence in this vector space.
See also
Baker's theorem
Dehn invariant
Gelfond–Schneider theorem
Hamel basis
Hodge conjecture
Lindemann–Weierstrass theorem
Linear flow on the torus
Schanuel's conjecture
Bibliography
Dynamical systems
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https://en.wikipedia.org/wiki/Latch-up
|
In electronics, a latch-up is a type of short circuit which can occur in an integrated circuit (IC). More specifically, it is the inadvertent creation of a low-impedance path between the power supply rails of a MOSFET circuit, triggering a parasitic structure which disrupts proper functioning of the part, possibly even leading to its destruction due to overcurrent. A power cycle is required to correct this situation.
The parasitic structure is usually equivalent to a thyristor (or SCR), a PNPN structure which acts as a PNP and an NPN transistor stacked next to each other. During a latch-up when one of the transistors is conducting, the other one begins conducting too. They both keep each other in saturation for as long as the structure is forward-biased and some current flows through it - which usually means until a power-down. The SCR parasitic structure is formed as a part of the totem-pole PMOS and NMOS transistor pair on the output drivers of the gates.
The latch-up does not have to happen between the power rails - it can happen at any place where the required parasitic structure exists. A common cause of latch-up is a positive or negative voltage spike on an input or output pin of a digital chip that exceeds the rail voltage by more than a diode drop. Another cause is the supply voltage exceeding the absolute maximum rating, often from a transient spike in the power supply. It leads to a breakdown of an internal junction. This frequently happens in circuits which use multiple supply voltages that do not come up in the required sequence on power-up, leading to voltages on data lines exceeding the input rating of parts that have not yet reached a nominal supply voltage. Latch-ups can also be caused by an electrostatic discharge event.
Another common cause of latch-ups is ionizing radiation which makes this a significant issue in electronic products designed for space (or very high-altitude) applications. A single event latch-up is a latch-up caused by a si
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https://en.wikipedia.org/wiki/Japanese%20sleeper%20ray
|
The Japanese sleeper ray (Narke japonica) is a species of electric ray in the family Narkidae. It is common in the inshore and offshore waters of the northwestern Pacific Ocean from southern Japan to southern China. Growing up to long, the Japanese sleeper ray has a nearly circular pectoral fin disc colored reddish to chocolate brown above, sometimes with darker or lighter spots, and lighter brown below. The spiracles behind its small eyes have raised, smooth rims. Its short and muscular tail bears a single dorsal fin positioned aft of the rounded pelvic fins, and terminates in a large caudal fin.
Inhabiting shallow, sandy areas near rocky reefs, the Japanese sleeper ray is a bottom-dwelling predator of invertebrates. Like other members of its family, it can produce a strong electric shock from its electric organs for defensive purposes. Females give live birth to litters of up to five pups. The gestating young are sustained at first by yolk, and later by histotroph ("uterine milk"). The International Union for Conservation of Nature (IUCN) has listed this species as Vulnerable, due to its susceptibility to trawl fisheries that operate intensively throughout its range.
Taxonomy
The first specimens of the Japanese sleeper ray known to science were four fish collected from Japan by German naturalists Philipp Franz von Siebold and Heinrich Burger during the second quarter of the 19th century. The specimens were stuffed and deposited at the National Museum of Natural History in Leiden; three of them were labeled as "Narcine spec." and one as "Narcine timlei". This material formed the basis for a description authored by Coenraad Jacob Temminck and Hermann Schlegel, which was published in 1850 as part of Fauna Japonica, a series of monographs on Japanese zoology. Temminck and Schlegel assigned the new species to the subgenus Astrape of the genus Torpedo; later authors would synonymize Astrape with Narke. In 1947, Marinus Boeseman reexamined the four original specimens
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https://en.wikipedia.org/wiki/76th%20meridian%20east
|
The meridian 76° east of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, Asia, the Indian Ocean, the Southern Ocean, and Antarctica to the South Pole.
The 76th meridian east forms a great circle with the 104th meridian west.
From Pole to Pole
Starting at the North Pole and heading south to the South Pole, the 76th meridian east passes through:
{| class="wikitable plainrowheaders"
! scope="col" width="120" | Co-ordinates
! scope="col" | Country, territory or sea
! scope="col" | Notes
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Arctic Ocean
| style="background:#b0e0e6;" |
|-valign="top"
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Kara Sea
| style="background:#b0e0e6;" | Passing just west of Vize Island, Krasnoyarsk Krai,
|-
|
! scope="row" |
| Yamalo-Nenets Autonomous Okrug — Vilkitsky Island
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Kara Sea
| style="background:#b0e0e6;" | Passing just west of Neupokoyeva Island, Yamalo-Nenets Autonomous Okrug,
|-
|
! scope="row" |
| Yamalo-Nenets Autonomous Okrug — Gydan Peninsula
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Khalmyer Bay
| style="background:#b0e0e6;" |
|-
|
! scope="row" |
| Yamalo-Nenets Autonomous Okrug — Gydan Peninsula
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Taz Estuary
| style="background:#b0e0e6;" |
|-valign="top"
|
! scope="row" |
| Yamalo-Nenets Autonomous Okrug Khanty-Mansi Autonomous Okrug — from Tomsk Oblast — from Omsk Oblast — from Novosibirsk Oblast — from Omsk Oblast — from Novosibirsk Oblast — from
|-
|
! scope="row" |
| Passing through Lake Balkhash
|-
|
! scope="row" |
|
|-valign="top"
|
! scope="row" |
| Xinjiang — passing through the city of Kashgar
|-
|
! scope="row" |
| Gilgit-Baltistan — for about 11 km, claimed by
|-valign="top"
|
! scope="row"
|
https://en.wikipedia.org/wiki/Multiphase%20heat%20transfer
|
A multiphase flow system is one characterized by the simultaneous presence of several phases, the two-phase system being the simplest case. The term ‘two-component’ is sometimes used to describe flows in which the phases consist of different chemical substances. However, since the same mathematics describes two-phase and two-component flows, the two expressions can be treated as synonymous.
Analysis of multiphase systems can include consideration of multiphase flow and multiphase heat transfer. The former occurs only if all parts are at the same temperature, but interphase heat transfer also occurs when the temperatures of the individual phases are different.
If different phases of the same pure substance are present in a multiphase system, interphase heat transfer will result in a change of phase, which is always accompanied by interphase mass transfer.
Definitions
A multiphase flow system is one characterized by the simultaneous presence of several phases, the two-phase system being the simplest case. The term ‘two-component’ is sometimes used to describe flows in which the phases consist of different chemical substances. For example, steam-water flows are two-phase, while air-water flows are two-component. Some two-component flows (mostly liquid-liquid) technically consist of a single phase but are identified as two-phase flows in which the term “phase” is applied to each of the components. Since the same mathematics describes two-phase and two-component flows, the two expressions can be treated as synonymous.
Multiphase flow versus heat transfer
The analysis of multiphase systems can include consideration of multiphase flow and multiphase heat transfer. When all of the phases in a multiphase system exist at the same temperature, multiphase flow is the only concern. However, when the temperatures of the individual phases are different, interphase heat transfer also occurs.
Phase-change heat transfer
If different phases of the same pure substance are present
|
https://en.wikipedia.org/wiki/Transcription%20factor%20II%20A
|
Transcription factor TFIIA is a nuclear protein involved in the RNA polymerase II-dependent transcription of DNA. TFIIA is one of several general (basal) transcription factors (GTFs) that are required for all transcription events that use RNA polymerase II. Other GTFs include TFIID, a complex composed of the TATA binding protein TBP and TBP-associated factors (TAFs), as well as the factors TFIIB, TFIIE, TFIIF, and TFIIH. Together, these factors are responsible for promoter recognition and the formation of a transcription preinitiation complex (PIC) capable of initiating RNA synthesis from a DNA template.
Functions
TFIIA interacts with the TBP subunit of TFIID and aids in the binding of TBP to TATA-box containing promoter DNA. Interaction of TFIIA with TBP facilitates formation of and stabilizes the preinitiation complex. Interaction of TFIIA with TBP also results in the exclusion of negative (repressive) factors that might otherwise bind to TBP and interfere with PIC formation. TFIIA also acts as a coactivator for some transcriptional activators, assisting with their ability to increase, or activate, transcription. The requirement for TFIIA in vitro transcription systems has been variable, and it can be considered either as a GTF and/or a loosely associated TAF-like coactivator. Genetic analysis in yeast has shown that TFIIA is essential for viability.
Structure
TFIIA is a heterodimer with two subunits: one large unprocessed (subunit 1, or alpha/beta; gene name ) and one small (subunit 2, or gamma; gene name ). It was originally believed to be a heterotrimer of an alpha (p35), a beta (p19) and a gamma subunit (p12). In humans, the sizes of the encoded proteins are approximately 55 kD and 12 kD. Both genes are present in species ranging from humans to yeast, and their protein products interact to form a complex composed of a beta barrel domain and an alpha helical bundle domain. It is the N-terminal and C-terminal regions of the large subunit that particip
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https://en.wikipedia.org/wiki/High%20Performance%20Storage%20System
|
High Performance Storage System (HPSS) is a flexible, scalable, policy-based, software-defined Hierarchical Storage Management product developed by the HPSS Collaboration. It provides scalable hierarchical storage management (HSM), archive, and file system services using cluster, LAN and SAN technologies to aggregate the capacity and performance of many computers, disks, disk systems, tape drives, and tape libraries.
Architecture
HPSS supports a variety of methods for accessing and creating data. Among them are support for FTP, parallel FTP, FUSE (Linux), as well as a robust client API with support for parallel I/O.
As of version 7.5, HPSS has full support on Linux. The HPSS client API is supported on AIX, Linux, and Solaris.
The implementation is built around IBM's Db2, a scalable relational database management system.
The HPSS Collaboration
In early 1992, several United States Department of Energy (DOE) National Laboratories — Lawrence Livermore (LLNL), Los Alamos (LANL), Oak Ridge (ORNL), and Sandia (SNL) — joined with IBM to form the National Storage Laboratory (NSL). The NSL's purpose was to commercialize software and hardware technologies that would overcome computing and data storage bottlenecks. The NSL's research on data storage gave birth to the collaboration which produces HPSS. This collaboration began in the fall of 1992 and involved IBM's Houston Global Services and five DOE national labs (Lawrence Berkeley [LBL], LLNL, LANL, ORNL, and SNL). At that time, the HPSS design team at the DOE national laboratories and IBM recognized there would be a data storage explosion driven by computing power rising to teraflops/petaflops requiring data stored in HSMs to rise to petabytes and beyond, data transfer rates with the HSM to rise to gigabytes/s and higher, and daily throughput with a HSM in tens of terabytes per day. Therefore, the collaboration set out to design and deploy a system that would scale by a factor of 1,000 or more and evolve from the ba
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https://en.wikipedia.org/wiki/Medical%20geology
|
Medical geology is an interdisciplinary scientific field studying the relationship between natural geological factors and their effects on human and animal health. The Commission on Geological Sciences for Environmental Planning defines medical geology as "the science dealing with the influence of ordinary environmental factors on the geographical distribution of health problems in man and animals."
In its broadest sense, medical geology studies exposure to or deficiency of trace elements and minerals; inhalation of ambient and anthropogenic mineral dusts and volcanic emissions; transportation, modification and concentration of organic compounds; and exposure to radionuclides, microbes and pathogens.
History
Many have deemed medical geology as a new field, when in actuality it is re-emerging. Hippocrates and Aristotle first recognized the relationship between human diseases and the earth's elements. This field ultimately depends on a number of different fields coming and working together to solve some of the earth's mysteries. The scientific term for this field is hydrobiogeochemoepidemiopathoecology; however, it is more commonly known as medical geology. It was established in 1990 by the International Union of Geological Sciences. Paracelsus, the "father of pharmacology" (1493–1541), stated that "all substances are poisons, there is none which is not a poison. The right dosage differentiates a poison and a remedy." This passage sums up the idea of medical geology. The goal of this field is to find the right balance and intake of elements/minerals in order to improve and maintain health.
Examples of research in medical geology include:
Studies on the impact of contaminant mobility as a result of extreme weather events such as flooding.
Lead and other heavy metal exposure resulting from dust and other particulates
Asbestos exposure such as amphibole asbestos dusts in Libby, Montana
Fungal infection resulting from airborne dust, such as Valley Fever or coccidio
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https://en.wikipedia.org/wiki/Reporter%20gene
|
In molecular biology, a reporter gene (often simply reporter) is a gene that researchers attach to a regulatory sequence of another gene of interest in bacteria, cell culture, animals or plants. Such genes are called reporters because the characteristics they confer on organisms expressing them are easily identified and measured, or because they are selectable markers. Reporter genes are often used as an indication of whether a certain gene has been taken up by or expressed in the cell or organism population.
Common reporter genes
To introduce a reporter gene into an organism, scientists place the reporter gene and the gene of interest in the same DNA construct to be inserted into the cell or organism. For bacteria or prokaryotic cells in culture, this is usually in the form of a circular DNA molecule called a plasmid. For viruses, this is known as a viral vector. It is important to use a reporter gene that is not natively expressed in the cell or organism under study, since the expression of the reporter is being used as a marker for successful uptake of the gene of interest.
Commonly used reporter genes that induce visually identifiable characteristics usually involve fluorescent and luminescent proteins. Examples include the gene that encodes jellyfish green fluorescent protein (GFP), which causes cells that express it to glow green under blue light, the enzyme luciferase, which catalyzes a reaction with luciferin to produce light, and the red fluorescent protein from the gene . The GUS gene has been commonly used in plants but luciferase and GFP are becoming more common.
A common reporter in bacteria is the E. coli lacZ gene, which encodes the protein beta-galactosidase. This enzyme causes bacteria expressing the gene to appear blue when grown on a medium that contains the substrate analog X-gal. An example of a selectable marker which is also a reporter in bacteria is the chloramphenicol acetyltransferase (CAT) gene, which confers resistance to the antibioti
|
https://en.wikipedia.org/wiki/VEK-30%20protein%20domain
|
In molecular biology, the protein domain VEK-30, is a 30-amino acid long, internal peptide present within bacterial organisms that acts as an epitope or antigenic determinant. It increases the pathogenicity of the cell. More specifically, it is found in streptococcal M-like plasminogen (Pg)-binding protein (PAM) from gram-positive group-A streptococci (GAS). VEK-30 represents an epitope within PAM that shows high affinity for the lysine binding site (LBS) of the kringle-2 (K2) domain of human (h)Pg.
Plasminogen
Plasminogen (Pg) is an important mediator of angiostatin production in the fibrinolytic pathway. Plasminogen is made up of five subunit kringle molecules (Pg-K1 to Pg-K5), of which the first three make the protein angiostatin. VEK-30 is a protein domain of the group A streptococcal protein PAM. It binds to Pg-K2 domain of angiostatin and activates the molecule to mediate its anti-angiogenic effects. VEK-30 binds to angiostatin via a C-terminal lysine with argininyl and glutamyl side chain residues known as a 'through space isostere'.
Function
Since VEK-30 binds to Pg-K2 domain of angiostatin, its function is crucial to blood clotting, and in lower organisms increase their pathogenicity.
Structure
In solution, it has been found that VEK-30, exhibited the canonical fold of a kringle domain,
including a lack of regular secondary structure.
|
https://en.wikipedia.org/wiki/Quantum%20Fourier%20transform
|
In quantum computing, the quantum Fourier transform (QFT) is a linear transformation on quantum bits, and is the quantum analogue of the discrete Fourier transform. The quantum Fourier transform is a part of many quantum algorithms, notably Shor's algorithm for factoring and computing the discrete logarithm, the quantum phase estimation algorithm for estimating the eigenvalues of a unitary operator, and algorithms for the hidden subgroup problem. The quantum Fourier transform was discovered by Don Coppersmith.
The quantum Fourier transform can be performed efficiently on a quantum computer with a decomposition into the product of simpler unitary matrices. The discrete Fourier transform on amplitudes can be implemented as a quantum circuit consisting of only Hadamard gates and controlled phase shift gates, where is the number of qubits. This can be compared with the classical discrete Fourier transform, which takes gates (where is the number of bits), which is exponentially more than .
The quantum Fourier transform acts on a quantum state vector (a quantum register), and the classical Fourier transform acts on a vector. Both types of vectors can be written as lists of complex numbers. In the quantum case it is a sequence of probability amplitudes for all the possible outcomes upon measurement (called basis states, or eigenstates). Because measurement collapses the quantum state to a single basis state, not every task that uses the classical Fourier transform can take advantage of the quantum Fourier transform's exponential speedup.
The best quantum Fourier transform algorithms known (as of late 2000) require only gates to achieve an efficient approximation, provided that a controlled phase gate is implemented as a native operation.
Definition
The quantum Fourier transform is the classical discrete Fourier transform applied to the vector of amplitudes of a quantum state, which usually has length .
The classical Fourier transform acts on a vector and ma
|
https://en.wikipedia.org/wiki/Certificate-based%20encryption
|
Certificate-based encryption is a system in which a certificate authority uses ID-based cryptography to produce a certificate. This system gives the users both implicit and explicit certification, the certificate can be used as a conventional certificate (for signatures, etc.), but also implicitly for the purpose of encryption.
Example
A user Alice can doubly encrypt a message using another user's (Bob) public key and his (Bob's) identity.
This means that the user (Bob) cannot decrypt it without a currently valid certificate and also that the certificate authority cannot decrypt the message as they don't have the user's private key (i.e., there is no implicit escrow as with ID-based cryptography, as the double encryption means they cannot decrypt it solely with the information they have).Certificate is the trust between two parties.
Key revocation
Key revocation can be added to the system by requiring a new certificate to be issued as frequently as the level of security requires. Because the certificate is "public information", it does not need to be transmitted over a secret channel. The downside of this is the requirement for regular communication between users and the certificate authority, which means the certificate authority is more vulnerable to electronic attacks (such as denial-of-service attacks) and also that such attacks could effectively stop the system from working. This risk can be partially but not completely reduced by having a hierarchy of multiple certificate authorities.
Practical applications
The best example of practical use of certificate-based encryption is Content Scrambling System (CSS), which is used to encode DVD movies in such a way as to make them playable only in a part of the world where they are sold. However, the fact that the region decryption key is stored on the hardware level in the DVD players substantially weakens this form of protection.
See also
X.509
Certificate server
|
https://en.wikipedia.org/wiki/Health%20ecology
|
Health ecology (also known as eco-health) is an emerging field that studies the impact of ecosystems on human health. It examines alterations in the biological, physical, social, and economic environments to understand how these changes affect mental and physical human health. Health ecology focuses on a transdisciplinary approach to understanding all the factors which influence an individual's physiological, social, and emotional well-being.
Eco-health studies often involve environmental pollution. Some examples include an increase in asthma rates due to air pollution, or PCB contamination of game fish in the Great Lakes of the United States. However, health ecology is not necessarily tied to environmental pollution. For example, research has shown that habitat fragmentation is the main factor that contributes to increased rates of Lyme disease in human populations.
History
Ecosystem approaches to public health emerged as a defined field of inquiry and application in the 1990s, primarily through global research supported by the International Development Research Centre (IDRC) in Ottawa, Canada (Lebel, 2003). However, this was a resurrection of an approach to health and ecology traced back to Hippocrates in Western societies. It can also be traced back to earlier eras in Eastern societies. The approach was also popular among scientists in the centuries. However, it fell out of common practice in the twentieth century, when technical professionalism and expertise were assumed sufficient to manage health and disease. In this relatively brief era, evaluating the adverse impacts of environmental change (both the natural and artificial environment) on human health was assigned to medicine and environmental health.
Integrated approaches to health and ecology re-emerged in the 20th century. These revolutionary movements were built on a foundation laid by earlier scholars, including Hippocrates, Rudolf Virchow, and Louis Pasteur. In the 20th century, Calvin Schwabe coi
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https://en.wikipedia.org/wiki/South%20Atlantic%20Anomaly
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The South Atlantic Anomaly (SAA) is an area where Earth's inner Van Allen radiation belt comes closest to Earth's surface, dipping down to an altitude of . This leads to an increased flux of energetic particles in this region and exposes orbiting satellites (including the ISS) to higher-than-usual levels of ionizing radiation.
The effect is caused by the non-concentricity of Earth and its magnetic dipole and has been observed to be increasing in intensity recently. The SAA is the near-Earth region where Earth's magnetic field is weakest relative to an idealized Earth-centered dipole field.
Definition
The area of the SAA is confined by the intensity of Earth's magnetic field at less than 32,000 nanotesla at sea level, which corresponds to the dipolar magnetic field at ionospheric altitudes. However, the field itself varies in intensity as a gradient.
Position and shape
The Van Allen radiation belts are symmetric about the Earth's magnetic axis, which is tilted with respect to the Earth's rotational axis by an angle of approximately 11°. The intersection between the magnetic and rotation axes of the Earth is located not at the Earth's center, but some away. Because of this asymmetry, the inner Van Allen belt is closest to the Earth's surface over the south Atlantic Ocean where it dips down to in altitude, and farthest from the Earth's surface over the north Pacific Ocean.
If Earth's magnetism is represented by a bar magnet of small size but strong intensity ("magnetic dipole"), the SAA variation can be illustrated by placing the magnet not in the plane of the Equator, but some small distance North, shifted more or less in the direction of Singapore. As a result, over northern South America and the south Atlantic, near Singapore's antipodal point, the magnetic field is relatively weak, resulting in a lower repulsion to trapped particles of the radiation belts there, and as a result these particles reach deeper into the upper atmosphere than they otherwise would.
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https://en.wikipedia.org/wiki/Freedom%20to%20Read%20Foundation
|
The Freedom to Read Foundation (FTRF) is an American non-profit anti-censorship organization, established in 1969 by the American Library Association. The organization has been active in First Amendment-based challenges to book removals from libraries, and in anti-surveillance work. In addition to its legal work, the FTRF engages in advocacy and public awareness, such as its sponsorship of the annual celebration of "Banned Books Week".
History
The FTRF was established in 1969 by members of the American Library Association, including Judith Krug, Alexander Allain, and Carrie C Robinson. The organization was founded as "the American Library Association's response to its members' interest in having adequate means to support and defend librarians whose positions are jeopardized because of their resistance to abridgments of the First Amendment; and to set legal precedent for the freedom to read on behalf of all people".
The FTRF was set up in conjunction with the ALA's Office of Intellectual Freedom instead of as a separate entity because of the work ALA was already doing to protect the First Amendment and intellectual freedom. When the Foundation was being planned for and organized, Allain expressed concern in a letter to the Director of the Intellectual Freedom Office, Judith Krug, that ALA members would forget what the ALA has done and continues to do for intellectual freedom by covering themselves in this new umbrella of aid and assistance in the FTRF. Allain felt that there should be overlap of both organizations so that the focus remained centered on intellectual freedom and could be worked on in harmony.
Allain also felt that in forming the FTRF with the ALA, the Foundation would be able to benefit from some of the clout and connections that ALA already had. He also suggested keeping policies between the two organizations similar because of his belief in the good work that the ALA does; he was continuously concerned about the ALA in his creation of the foundat
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https://en.wikipedia.org/wiki/Matrix%20difference%20equation
|
A matrix difference equation is a difference equation in which the value of a vector (or sometimes, a matrix) of variables at one point in time is related to its own value at one or more previous points in time, using matrices. The order of the equation is the maximum time gap between any two indicated values of the variable vector. For example,
is an example of a second-order matrix difference equation, in which is an vector of variables and and are matrices. This equation is homogeneous because there is no vector constant term added to the end of the equation. The same equation might also be written as
or as
The most commonly encountered matrix difference equations are first-order.
Nonhomogeneous first-order case and the steady state
An example of a nonhomogeneous first-order matrix difference equation is
with additive constant vector . The steady state of this system is a value of the vector which, if reached, would not be deviated from subsequently. is found by setting in the difference equation and solving for to obtain
where is the identity matrix, and where it is assumed that is invertible. Then the nonhomogeneous equation can be rewritten in homogeneous form in terms of deviations from the steady state:
Stability of the first-order case
The first-order matrix difference equation is stable—that is, converges asymptotically to the steady state —if and only if all eigenvalues of the transition matrix (whether real or complex) have an absolute value which is less than 1.
Solution of the first-order case
Assume that the equation has been put in the homogeneous form . Then we can iterate and substitute repeatedly from the initial condition , which is the initial value of the vector and which must be known in order to find the solution:
and so forth, so that by mathematical induction the solution in terms of is
Further, if is diagonalizable, we can rewrite in terms of its eigenvalues and eigenvectors, giving the solution as
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