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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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Cover Test
A cover test or cover-uncover test is an objective determination of the presence and amount of ocular deviation. It is typically performed by orthoptists, ophthalmologists and optometrists during eye examinations. The two primary types of cover tests are: The test involves having the patient focusing on both a distance as well as near object at different times during the examination. A cover is placed over an eye for a short moment then removed while observing both eyes for movement. The misaligned eye will deviate inwards or outwards. The process is repeated on both eyes and then with the child focusing on a distant object. The cover test is used to determine both the type of ocular deviation and measure the amount of deviation. The two primary types of ocular deviations are the tropia and the phoria. A tropia is a misalignment of the two eyes when a patient is looking with both eyes uncovered. A phoria (or latent deviation) only appears when binocular viewing is broken and the two eyes are no longer looking at the same object. The unilateral cover test is performed by having the patient focus on an object then covering the fixating eye and observing the movement of the other eye. If the eye was exotropic, covering the fixating eye will cause an inwards movement; and esotropic if covering the fixating eye will cause an outwards movement. The alternating cover test, or cross cover test is used to detect total deviation (tropia + phoria).
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  • 16 Nov 2022
Topic Review
Parallel Tree Contraction
In computer science, parallel tree contraction is a broadly applicable technique for the parallel solution of a large number of tree problems, and is used as an algorithm design technique for the design of a large number of parallel graph algorithms. Parallel tree contraction was introduced by Gary L. Miller and John H. Reif, and has subsequently been modified to improve efficiency by X. He and Y. Yesha, Hillel Gazit, Gary L. Miller and Shang-Hua Teng and many others. Tree contraction has been used in designing many efficient parallel algorithms, including expression evaluation, finding lowest common ancestors, tree isomorphism, graph isomorphism, maximal subtree isomorphism, common subexpression elimination, computing the 3-connected components of a graph, and finding an explicit planar embedding of a planar graph Based on the research and work on parallel tree contraction, various algorithms have been proposed targeting to improve the efficiency or simplicity of this topic. This article hereby focuses on a particular solution, which is a variant of the algorithm by Miller and Reif, and its application.
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  • 16 Nov 2022
Topic Review
Soyuz TM-21
Soyuz TM-21 was a crewed Soyuz spaceflight to Mir. The mission launched from Baikonur Cosmodrome, atop a Soyuz-U2 carrier rocket, at 06:11:34 UTC on March 14, 1995. The flight marked the first time thirteen humans were flying in space simultaneously, with three aboard the Soyuz, three aboard Mir and seven aboard Space Shuttle Endeavour, flying STS-67. The spacecraft carried expedition EO-18 to the space station. This included the first American astronaut to launch on a Soyuz spacecraft and board Mir, Norman Thagard, for the American Thagard Increment aboard the station, which was the first Increment of the Shuttle-Mir program. The three crew members it launched were relieved by Space Shuttle Atlantis during STS-71, when they were replaced by expedition EO-19. The crew returned to earth aboard Soyuz TM-21 on September 11, 1995.
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  • 16 Nov 2022
Topic Review
Glossary of Graph Theory Terms
This is a glossary of graph theory terms. Graph theory is the study of graphs, systems of nodes or vertices connected in pairs by edges.
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  • 16 Nov 2022
Topic Review
Leadership
Leadership is both a research area and a practical skill encompassing the ability of an individual or organization to "lead" or guide other individuals, teams, or entire organizations. Specialist literature debates various viewpoints, contrasting Eastern and Western approaches to leadership, and also (within the West) United States versus European approaches. U.S. academic environments define leadership as "a process of social influence in which a person can enlist the aid and support of others in the accomplishment of a common task". Leadership seen from a European and non-academic perspective encompasses a view of a leader who can be moved not only by communitarian goals but also, as the European researcher Daniele Trevisani sugggests, by the search for personal power. Studies of leadership have produced theories involving traits, situational interaction, function, behavior, power, vision and values, charisma, and intelligence, among others.
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  • 21 Nov 2022
Topic Review
Ket
Ket is an open source algebra editor. It is distinct from other editors which focus on automated computation such as integration or equation solving (Mathematica, Maple etc.) or on the presentation quality of the resulting document (e.g. LaTeX). The focus of Ket is to enable the user to perform algebra quickly and efficiently. It is therefore closer to a text editor, whiteboard or to the back of an envelope. However, it does provide a range of tools to automate the individual steps of algebra.
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  • 16 Nov 2022
Topic Review
Republic
A republic (Latin: res publica, meaning "public affair") is a form of government in which the country is considered a "public matter", not the private concern or property of the rulers. The primary positions of power within a republic are attained, through democracy, oligarchy, or a mix thereof, rather than being unalterably occupied. It has become the opposing form of government to a monarchy and has therefore no monarch as head of state. (As of 2017), 159 of the world's 206 sovereign states use the word "republic" as part of their official names – not all of these are republics in the sense of having elected governments, nor is the word "republic" used in the names of all nations with elected governments. The word republic comes from the Latin term res publica, which literally means "public thing", "public matter", or "public affair" and was used to refer to the state as a whole. The term developed its modern meaning in reference to the constitution of the ancient Roman Republic, lasting from the overthrow of the kings in 509 BC to the establishment of the Empire in 27 BC. This constitution was characterized by a Senate composed of wealthy aristocrats and wielding significant influence; several popular assemblies of all free citizens, possessing the power to elect magistrates and pass laws; and a series of magistracies with varying types of civil and political authority. Most often a republic is a single sovereign state, but there are also sub-sovereign state entities that are referred to as republics, or that have governments that are described as "republican" in nature. For instance, Article IV of the United States Constitution "guarantee[s] to every State in this Union a Republican form of Government". Another example is the Soviet Union which described itself as being a group of "Soviet Socialist Republics", in reference to the 15 individually federal, multinational, top-level subdivisions or republics. In the context of American constitutional law, the definition of republic refers specifically to a form of government in which elected individuals represent the citizen body and exercise power according to the rule of law under a constitution, including separation of powers with an elected head of state, referred to as a constitutional republic or representative democracy.
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  • 16 Nov 2022
Topic Review
Antibiotics in Poultry Farming
Antibiotics in poultry farming is the controversial prophylactic use of antibiotics in the poultry farming industry in the USA. This does not represent the position in other countries. Antibiotics have been applied in mass quantities since 1951 in the USA, when its Food and Drug Administration (FDA) approved their use. Three years prior to the FDA's approval, scientists were investigating a phenomenon in which chickens who were rooting through bacteria-rich manure were displaying signs of greater health than those who did not. Through testing, it was discovered that chickens who were fed a variety of vitamin B12 manufactured with the residue of a certain antibiotic grew 50 percent faster than those chickens who were fed B12 manufactured from a different source. Further testing confirmed that use of antibiotics did improve the health of the chickens, resulting in the chickens laying more eggs and experiencing lower mortality rates and less illness. Upon this discovery, farmers transitioned from expensive animal proteins to comparatively inexpensive antibiotics and B12. Chickens were now reaching their market weight at a much faster rate and at a lower cost. With a growing population and greater demand on the farmers, antibiotics appeared to be an ideal and cost-effective way to increase the output of poultry. Since this discovery, antibiotics have been routinely used in poultry production, but more recently have been the topic of debate secondary to the fear of bacterial antibiotic resistance.
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  • 16 Nov 2022
Topic Review
Fossil Fuel Phase-Out
Fossil fuel phase-out is the gradual reduction of the use of fossil fuels to zero use. Current efforts in fossil fuel phase-out involve replacing fossil fuels with alternative energy sources in sectors such as transport, heating and industry.
  • 2.1K
  • 16 Nov 2022
Topic Review
Eurabia
Eurabia is a political neologism, a portmanteau of Europe and Arabia, used to describe a far-right anti-Muslim conspiracy theory, involving globalist entities allegedly led by French and Arab powers, to Islamise and Arabise Europe, thereby weakening its existing culture and undermining a previous alignment with the United States and Israel. The term was first used in the 1970s as the title of a newsletter and the concept itself developed by Bat Ye'or (pen name of Gisèle Littman) in the early 2000s and is described in her 2005 book titled Eurabia: The Euro‐Arab Axis. Benjamin Lee of the Centre for Research and Evidence on Security Threats at the University of Lancaster describes her work as arguing that Europe "has surrendered to Islam and is in a state of submission (described as dhimmitude) in which Europe is forced to deny its own culture, stand silently by in the face of Muslim atrocities, accept Muslim immigration, and pay tribute through various types of economic assistance." According to the theory, the blame rests with a range of groups including communists, fascists, the media, universities, mosques and Islamic cultural centres, European bureaucrats, and the Euro-Arab Dialogue. The term has gained some public interest and has been used and discussed across a wide range of the political spectrum, including right-wing activists, self-described "conservatives" and counter-jihad and other anti-Islamism activists. Bat Ye'or's "mother conspiracy theory" has been used for further subtheories. The narrative grew important in expressing anti-Islamist sentiments and was used by movements like Stop Islamisation of Europe. It gained renewed interest after the September 11 attacks and the use of the term by 2011 Norway attacker, Anders Behring Breivik. Ye'or's thesis has come under criticism by scholars, which intensified after Breivik's crime. The conspiracy has been described as having resemblance to the anti-Semitic Protocols of the Elders of Zion. Eurabia is also discussed in classical anti-Europeanism, a strong influence in the culture of the United States and in the notion of American exceptionalism, which sometimes sees Europe on the decline or as a rising rival power, or, as is the case here, both.
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  • 16 Nov 2022
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