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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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Elephant
Elephants are the largest existing land animals. Three living species are currently recognised: the African bush elephant, the African forest elephant, and the Asian elephant. They are an informal grouping within the proboscidean family Elephantidae. Elephantidae is the only surviving family of proboscideans; extinct members include the mastodons. Elephantidae also contains several extinct groups, including the mammoths and straight-tusked elephants. African elephants have larger ears and concave backs, whereas Asian elephants have smaller ears, and convex or level backs. The distinctive features of all elephants include a long proboscis called a trunk, tusks, large ear flaps, massive legs, and tough but sensitive skin. The trunk is used for breathing, bringing food and water to the mouth, and grasping objects. Tusks, which are derived from the incisor teeth, serve both as weapons and as tools for moving objects and digging. The large ear flaps assist in maintaining a constant body temperature as well as in communication. The pillar-like legs carry their great weight. Elephants are scattered throughout sub-Saharan Africa, South Asia, and Southeast Asia and are found in different habitats, including savannahs, forests, deserts, and marshes. They are herbivorous, and they stay near water when it is accessible. They are considered to be keystone species, due to their impact on their environments. Elephants have a fission–fusion society, in which multiple family groups come together to socialise. Females (cows) tend to live in family groups, which can consist of one female with her calves or several related females with offspring. The groups, which do not include bulls, are usually led by the oldest cow, known as the matriarch. Males (bulls) leave their family groups when they reach puberty and may live alone or with other males. Adult bulls mostly interact with family groups when looking for a mate. They enter a state of increased testosterone and aggression known as musth, which helps them gain dominance over other males as well as reproductive success. Calves are the centre of attention in their family groups and rely on their mothers for as long as three years. Elephants can live up to 70 years in the wild. They communicate by touch, sight, smell, and sound; elephants use infrasound, and seismic communication over long distances. Elephant intelligence has been compared with that of primates and cetaceans. They appear to have self-awareness, and appear to show empathy for dying and dead family members. African bush elephants and Asian elephants are listed as endangered and African forest elephants as critically endangered by the International Union for Conservation of Nature (IUCN). One of the biggest threats to elephant populations is the ivory trade, as the animals are poached for their ivory tusks. Other threats to wild elephants include habitat destruction and conflicts with local people. Elephants are used as working animals in Asia. In the past, they were used in war; today, they are often controversially put on display in zoos, or exploited for entertainment in circuses. Elephants are highly recognisable and have been featured in art, folklore, religion, literature, and popular culture.
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  • 09 Nov 2022
Topic Review
Deep Sea Fish
Deep-sea fish are animals that live in the darkness below the sunlit surface waters, that is below the epipelagic or photic zone of the sea. The lanternfish is, by far, the most common deep-sea fish. Other deep sea fishes include the flashlight fish, cookiecutter shark, bristlemouths, anglerfish, viperfish, and some species of eelpout. Only about 2% of known marine species inhabit the pelagic environment. This means that they live in the water column as opposed to the benthic organisms that live in or on the sea floor. Deep-sea organisms generally inhabit bathypelagic (1000–4000m deep) and abyssopelagic (4000–6000m deep) zones. However, characteristics of deep-sea organisms, such as bioluminescence can be seen in the mesopelagic (200–1000m deep) zone as well. The mesopelagic zone is the disphotic zone, meaning light there is minimal but still measurable. The oxygen minimum layer exists somewhere between a depth of 700m and 1000m deep depending on the place in the ocean. This area is also where nutrients are most abundant. The bathypelagic and abyssopelagic zones are aphotic, meaning that no light penetrates this area of the ocean. These zones make up about 75% of the inhabitable ocean space. The epipelagic zone (0–200m) is the area where light penetrates the water and photosynthesis occurs. This is also known as the photic zone. Because this typically extends only a few hundred meters below the water, the deep sea, about 90% of the ocean volume, is in darkness. The deep sea is also an extremely hostile environment, with temperatures that rarely exceed 3 °C (37.4 °F) and fall as low as −1.8 °C (28.76 °F) (with the exception of hydrothermal vent ecosystems that can exceed 350 °C, or 662 °F), low oxygen levels, and pressures between 20 and 1,000 atmospheres (between 2 and 100 megapascals).
  • 5.8K
  • 08 Nov 2022
Topic Review
Restraining Order
A restraining order or protective order is an order used by a court to protect a person, business, company, establishment, or entity, and the general public, in a situation involving alleged domestic violence, harassment, stalking, or sexual assault. In the United States , every state has some form of domestic violence restraining order law, and many states also have specific restraining order laws for stalking and sexual assault. Restraining and personal protection order laws vary from one jurisdiction to another but all establish who can file for an order, what protection or relief a person can get from such an order, and how the order will be enforced. The court will order the adverse party to refrain from certain actions or require compliance with certain provisions. Failure to comply is a violation of the order which can result in the arrest and prosecution of the offender. Violations in some jurisdictions may also constitute criminal or civil contempt of court.
  • 1.3K
  • 08 Nov 2022
Topic Review
Bacteriologist (Professional)
A bacteriologist is a professional trained in bacteriology, a subdivision of microbiology. The duties of a bacteriologist include prevention, diagnosis and prognosis of diseases, as well as health care, and they may carry out various functions such as epidemiological surveillance, quality auditing with biotechnology development, basic research, management and teaching related to the career, scientist management, laboratory coordination and blood banks.
  • 1.8K
  • 03 Nov 2022
Topic Review
Content-Control Software
Content-control software, commonly referred to as an Internet filter, is software that restricts or controls the content an Internet user is capable to access, especially when utilised to restrict material delivered over the Internet via the Web, Email, or other means. Content-control software determines what content will be available or be blocked. Such restrictions can be applied at various levels: a government can attempt to apply them nationwide (see Internet censorship), or they can, for example, be applied by an ISP to its clients, by an employer to its personnel, by a school to its students, by a library to its visitors, by a parent to a child's computer, or by an individual user to their own computer. The motive is often to prevent access to content which the computer's owner(s) or other authorities may consider objectionable. When imposed without the consent of the user, content control can be characterised as a form of internet censorship. Some content-control software includes time control functions that empowers parents to set the amount of time that child may spend accessing the Internet or playing games or other computer activities. In some countries, such software is ubiquitous. In Cuba, if a computer user at a government-controlled Internet cafe types certain words, the word processor or web browser is automatically closed, and a "state security" warning is given.
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  • 08 Nov 2022
Topic Review
The Incoherence of the Philosophers
The Incoherence of the Philosophers (تهافت الفلاسفة Tahāfut al-Falāsifaʰ in Arabic) is the title of a landmark 11th-century work by the Persian theologian Abū Ḥāmid Muḥammad ibn Muḥammad al-Ghazali and a student of the Asharite school of Islamic theology criticizing the Avicennian school of early Islamic philosophy. Muslim philosophers such as Ibn Sina (Avicenna) and Al-Farabi (Alpharabius) are denounced in this book, as they follow Greek philosophy even when it contradicts Islam. The text was dramatically successful, and marked a milestone in the ascendance of the Asharite school within Islamic philosophy and theological discourse. The book favors faith over philosophy in matters specifically concerning metaphysics or knowledge of the divine.
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  • 08 Nov 2022
Topic Review
Stoned (Computer Virus)
Stoned is a boot sector computer virus created in 1987. It is one of the first viruses and is thought to have been written by a student in Wellington, New Zealand. By 1989 it had spread widely in New Zealand and Australia, and variants became very common worldwide in the early 1990s. A computer infected with the original version had a one in eight probability that the screen would declare: "Your PC is now Stoned!", a phrase found in infected boot sectors of infected floppy disks and master boot records of infected hard disks, along with the phrase "Legalise Marijuana". Later variants produced a range of other messages.
  • 1.4K
  • 03 Nov 2022
Topic Review
Coverage Data
A coverage is the digital representation of some spatio-temporal phenomenon. ISO 19123 provides the definition: Coverages play an important role in geographic information systems (GIS), geospatial content and services, GIS data processing, and data sharing. A coverage is represented by its "domain" (the universe of extent) and a collection representing the coverage's values at each defined location within its range. For example, a satellite image derived from remote sensing might record varying degrees of light pollution. Aerial photography, land cover data, and digital elevation models all provide coverage data. Generally, a coverage can be multi-dimensional, such as 1-D sensor timeseries, 2-D satellite images, 3-D x/y/t image time series or x/y/z geo tomograms, or 4-D x/y/z/t climate and ocean data. However, coverages are more general than just regularly gridded imagery. The corresponding standards (see below) address regular and irregular grids, point clouds, and general meshes. An interoperable service definition for navigating, accessing, processing, and aggregation of coverages is provided by the Open Geospatial Consortium (OGC) Web Coverage Service (WCS) suite and Web Coverage Processing Service (WCPS), a spatio-temporal coverage query language.
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  • 03 Nov 2022
Topic Review
Transfer-Appropriate Processing
Transfer-appropriate processing (TAP) is a type of state-dependent memory specifically showing that memory performance is not only determined by the depth of processing (where associating meaning with information strengthens the memory; see levels-of-processing effect), but by the relationship between how information is initially encoded and how it is later retrieved.
  • 1.1K
  • 03 Nov 2022
Topic Review
Anno Mundi
Anno Mundi (Latin for "in the year of the world"; Hebrew: לבריאת העולם, "to the creation of the world"), abbreviated as AM, or Year After Creation, is a calendar era based on the biblical accounts of the creation of the world and subsequent history. Two such calendar eras have seen notable use historically: While differences in biblical interpretation or in calculation methodology can produce some differences in the creation date, most results fall relatively close to one of these two dominant models. The primary reason for the disparity seems to lie in which underlying Biblical text is chosen (roughly 5500 BC based on the Greek Septuagint text, about 3750 BC based on the Hebrew Masoretic text). Most of the 1,732-year difference resides in numerical discrepancies in the genealogies of the two versions of the Book of Genesis. Patriarchs from Adam to Terah, the father of Abraham, are said to be older by as much as 100 years or more when they begat their named son in the Greek Septuagint than they were in the Latin Vulgate (Genesis 5; Genesis 11) or the Hebrew Tanakh (Gen 5; Gen 11). The net difference between the two major genealogies of Genesis is 1466 years (ignoring the "second year after the flood" ambiguity), 85% of the total difference. (See Dating creation.)
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  • 03 Nov 2022
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