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HandWiki is the world's largest wiki-style encyclopedia dedicated to science, technology and computing. It allows you to create and edit articles as long as you have external citations and login account. In addition, this is a content management environment that can be used for collaborative editing of original scholarly content, such as books, manuals, monographs and tutorials.

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Topic Review
Examples of Differential Equations
Differential equations arise in many problems in physics, engineering, and other sciences. The following examples show how to solve differential equations in a few simple cases when an exact solution exists.
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  • 11 Nov 2022
Topic Review
Control Rod
Control rods are used in nuclear reactors to control the rate of fission of the nuclear fuel – uranium or plutonium. Their compositions include chemical elements such as boron, cadmium, silver, hafnium, or indium, that are capable of absorbing many neutrons without themselves fissioning. These elements have different neutron capture cross sections for neutrons of various energies. Boiling water reactors (BWR), pressurized water reactors (PWR), and heavy-water reactors (HWR) operate with thermal neutrons, while breeder reactors operate with fast neutrons. Each reactor design can use different control rod materials based on the energy spectrum of its neutrons.
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Topic Review
2017–2018 Togolese Protests
The 2017–18 Togolese protests are a significant representation of civil unrest in Togo and against the 50 year rule of the father-son combination of Gnassingbé Eyadéma and Faure Gnassingbé. The protesters demanded that the president honour the 1992 constitution, and demanding that he step down immediately. Gnassingbé offered the protesters the option of enacting the two-term limit set in the constitution effective from 2018, thus ensuring that he could stay in power until 2030. This has been rejected by the opposition. However, on 8 May 2019 the Togolese Parliament voted unanimously to accept this amendment and imposed this non-retroactive term limit on the president's office. As the protests continued, the opposition started focusing more on protesting Gnassingbé's rule. Starting in August 2017, the opposition held protests on a near-weekly basis. The scale of the protests have been enormous, with some estimates claiming 800,000 present at one protest in a country of 6.6 million. The demonstrations are also taking place all over the country, even in the north, the traditional power base for the Gnassingbé family. The Togolese government has responded to these protests by shutting down the internet. The protesters utilised social media, with the hashtag #togodebut for publicity. The protests and police response have resulted in the deaths of at least 16 people, including two soldiers. In response to the protests, Gnassingbé offered some concessions to the opposition, but held onto power due to his crackdown on activists.
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Biography
Salman of Saudi Arabia
Salman bin Abdulaziz Al Saud (Arabic: سلمان بن عبد العزیز آل سعود Salmān ibn ‘Abd al-‘Azīz Āl Su‘ūd, Najdi Arabic pronunciation: [sælˈmæːn ben ˈʕæbd ælʕæˈziːz ʔæːl sæˈʕuːd]; born 31 December 1935) is a Saudi Arabian statesman who has ruled as King of Saudi Arabia since 23 January 2015. Salman is the 25th son of King Abdulaziz and his mother was
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Topic Review
Morpha
In biology, polymorphism is the occurrence of two or more clearly different morphs or forms, also referred to as alternative phenotypes, in the population of a species. To be classified as such, morphs must occupy the same habitat at the same time and belong to a panmictic population (one with random mating). Put simply, polymorphism is when there are two or more possibilities of a trait on a gene. For example, there is more than one possible trait in terms of a jaguar's skin colouring; they can be light morph or dark morph. Due to having more than one possible variation for this gene, it is termed 'polymorphism'. However, if the jaguar has only one possible trait for that gene, it would be termed "monomorphic". For example, if there was only one possible skin colour that a jaguar could have, it would be termed monomorphic. The term polyphenism can be used to clarify that the different forms arise from the same genotype. Genetic polymorphism is a term used somewhat differently by geneticists and molecular biologists to describe certain mutations in the genotype, such as single nucleotide polymorphisms that may not always correspond to a phenotype, but always corresponds to a branch in the genetic tree. See below. Polymorphism is common in nature; it is related to biodiversity, genetic variation, and adaptation. Polymorphism usually functions to retain a variety of forms in a population living in a varied environment.:126 The most common example is sexual dimorphism, which occurs in many organisms. Other examples are mimetic forms of butterflies (see mimicry), and human hemoglobin and blood types. According to the theory of evolution, polymorphism results from evolutionary processes, as does any aspect of a species. It is heritable and is modified by natural selection. In polyphenism, an individual's genetic makeup allows for different morphs, and the switch mechanism that determines which morph is shown is environmental. In genetic polymorphism, the genetic makeup determines the morph. The term polymorphism also refers to the occurrence of structurally and functionally more than two different types of individuals, called zooids, within the same organism. It is a characteristic feature of cnidarians. For example, Obelia has feeding individuals, the gastrozooids; the individuals capable of asexual reproduction only, the gonozooids, blastostyles; and free-living or sexually reproducing individuals, the medusae. Balanced polymorphism refers to the maintenance of different phenotypes in population.
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Topic Review
Panel Van
A panel van (or panelvan) is a form of solid (rigid-bodied, non-articulated) van, smaller than a lorry or truck, without rear side windows. In the UK this body style is referred to as a "car-derived van" and in North American as a "sedan delivery" (while the term "panel van" or "cargo van" generally refers to larger, truck-based vans such as the Ford E-Series and Chevrolet Express). In Australia panel vans were a development of the Australian "ute" (utility), a variety of pickup, based on a car chassis, these often utilizing the floorpan of the station wagon model. In North America a two-door station wagon base was used with only front seats and steel sheet-metal panels in place of the rear and side windows. Panel vans are widely used in many parts of the world for transporting cargo. In some national usages it is distinct from a purpose-designed van in that it is based on the chassis of a family car design. In places where they are distinct from a "van", they have less cargo space but better agility and maneuverability, making them particularly suited for cities with narrow streets or heavy traffic.
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Topic Review
Censorship of Twitter
Censorship of Twitter refers to Internet censorship by governments that block access to Twitter. Twitter censorship also includes governmental notice and take down requests to Twitter, which Twitter enforces in accordance with its Terms of Service when a government or authority submits a valid removal request to Twitter indicating that specific content (such as a tweet) is illegal in their jurisdiction.
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Biography
Sabine Hossenfelder
Sabine Hossenfelder (born 18 September 1976) is a German author and theoretical physicist who researches quantum gravity. She is a Research Fellow at the Frankfurt Institute for Advanced Studies where she leads the Superfluid Dark Matter group. She is the author of Lost in Math: How Beauty Leads Physics Astray, which explores the concept of elegance in fundamental physics and cosmology. Hosse
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  • 15 Nov 2022
Topic Review
Cromemco Dazzler
Cromemco's Dazzler (or TV DAZZLER) is a graphics card for S-100 bus computers. Released in 1976, it is the first commercial color bit-mapped graphics card available for microcomputers. Multiple Dazzler cards could be installed in a single machine and synced together, a feature which could, with minor modification, be used to genlock. Genlocked Dazzler cards drove ColorGraphics Weather Systems displays that generated most of the weather imagery seen on US television in the early 1980s.
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Biography
Dexter Holland
Bryan Keith "Dexter" Holland, Ph.D (born December 29, 1965)[1][2][3] is an American musician who is best known as the lead vocalist, rhythm guitarist, and primary songwriter of the American rock band The Offspring. In 2017 he attained a PhD in molecular biology. Holland attended Pacifica High School in Garden Grove, California, where he graduated as class valedictorian in 1984. During high sc
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