Summary

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.

Expand All
Entries
Topic Review
Cousin Marriage
A cousin marriage is a marriage where the partners are cousins (i.e. people with common grandparents or people who share other fairly recent ancestors). The practice was common in earlier times, and continues to be common in some societies today, though in some jurisdictions such marriages are prohibited. Worldwide, more than 10% of marriages are between first or second cousins. Cousin marriage is an important topic in anthropology and alliance theory. In some cultures and communities, cousin marriages are considered ideal and are actively encouraged and expected; in others, they are seen as incestuous and are subject to social stigma and taboo. Cousin marriage was historically practised by indigenous cultures in Australia, North America, South America, and Polynesia. Different religions have ranged from prohibiting up to sixth cousins from marrying (some forms of Hinduism and Catholicism) to freely allowing first cousin marriage (Protestantism, Islam and Judaism). In some jurisdictions, cousin marriage is legally prohibited, for example in China , Taiwan, North Korea, South Korea , the Philippines and 24 of the 50 United States. The laws of many jurisdictions set out the degree of consanguinity prohibited among sexual relations and marriage parties. Supporters of cousin marriage where it is banned may view the prohibition as discrimination, while opponents may appeal to moral or other arguments. Opinions vary widely as to the merits of the practice. Children of first-cousin marriages have an increased risk of autosomal recessive genetic disorders, and this risk is higher in populations that are already highly ethnically similar. Children of more distantly related cousins have less risk of these disorders, though still higher than the average population. A study indicated that between 1800 and 1965 in Iceland, more children and grandchildren were produced from marriages between third or fourth cousins (people with common great-great- or great-great-great-grandparents) than from other degrees of separation.
  • 58.8K
  • 13 Oct 2022
Topic Review
Feline Zoonosis
A feline zoonosis is a viral, bacterial, fungal, protozoan, nematode or arthropod infection that can be transmitted to humans from the domesticated cat, Felis catus. Some of these diseases are reemerging and newly emerging infections or infestations caused by zoonotic pathogens transmitted by cats. In some instances, the cat can display symptoms of infection (these may differ from the symptoms in humans) and sometimes the cat remains asymptomatic. There can be serious illnesses and clinical manifestations in people who become infected. This is dependent on the immune status and age of the person. Those who live in close association with cats are more prone to these infections. But those that do not keep cats as pets are also able to acquire these infections because of the transmission can be from cat feces and the parasites that leave their bodies. People can acquire cat-associated infections through bites, scratches or other direct contact of the skin or mucous membranes with the cat. This includes 'kissing' or letting the animal lick the mouth or nose. Mucous membranes are easily infected when the pathogen is in the mouth of the cat. Pathogens can also infect people when there is contact with animal saliva, urine and other body fluids or secretions. When fecal material is unintentionally ingested, infection can occur. A feline zoonosis can be acquired by a person by inhalation of aerosols or droplets coughed up by the cat. In the United States, thirty-two percent of homes have at least one cat. Some contagious infections such as campylobacteriosis and salmonellosis cause visible symptoms of the disease in cats. Other infections, such as cat scratch disease and toxoplasmosis, have no visible symptoms and are carried by apparently healthy cats.
  • 902
  • 13 Oct 2022
Topic Review
Amazon Relational Database Service
Amazon Relational Database Service (or Amazon RDS) is a distributed relational database service by Amazon Web Services (AWS). It is a web service running "in the cloud" designed to simplify the setup, operation, and scaling of a relational database for use in applications. Administration processes like patching the database software, backing up databases and enabling point-in-time recovery are managed automatically. Scaling storage and compute resources can be performed by a single API call to the AWS control plane on-demand. AWS does not offer an SSH connection to the underlying virtual machine as part of the managed service.
  • 1.3K
  • 12 Oct 2022
Topic Review
Indigenous Aryans
Indigenous Aryans, also known as the Out of India theory (OIT), is the idea that the Aryans are indigenous to the Indian subcontinent, and that the Indo-European languages radiated out from a homeland in India into their present locations. Reflecting traditional Indian views based on the Puranic chronology, the indigenist view proposes an older date than is generally accepted for the Vedic period, and argues that the Indus Valley Civilization was a Vedic civilization. In this view, "the Indian civilization must be viewed as an unbroken tradition that goes back to the earliest period of the Sindhu-Sarasvati (or Indus) tradition (7000 or 8000 BCE)." It is presented as an alternative to the established migration model, which proposes the Pontic steppe as the area of origin of the Indo-European languages. The proposal is based on traditional and religious views on Indian history and identity, and plays a signifcant role in Hindutva politics. Support for this idea mostly exists among Indian scholars of Hindu religion and the history and archaeology of India, and has no support in mainstream scholarship.
  • 13.5K
  • 13 Oct 2022
Topic Review
Severe Acute Respiratory Syndrome-related Coronavirus
Severe acute respiratory syndrome–related coronavirus (SARS-CoV or SARSr-CoV)[note 1] is a species of coronavirus that infects humans, bats and certain other mammals. It is an enveloped positive-sense single-stranded RNA virus that enters its host cell by binding to the angiotensin-converting enzyme 2 (ACE2) receptor. It is a member of the genus Betacoronavirus and subgenus Sarbecovirus. Two strains of the virus have caused outbreaks of severe respiratory diseases in humans: severe acute respiratory syndrome coronavirus (SARS-CoV or SARS-CoV-1), which caused the 2002–2004 outbreak of severe acute respiratory syndrome (SARS), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is causing the 2019–20 pandemic of coronavirus disease 2019 (COVID-19). There are hundreds of other strains of SARS-CoV, all of which are only known to infect non-human species: bats are a major reservoir of many strains of SARS-related coronaviruses, and several strains have been identified in palm civets, which were likely ancestors of SARS-CoV. The SARS-related coronavirus was one of several viruses identified by the World Health Organization (WHO) in 2016 as a likely cause of a future epidemic in a new plan developed after the Ebola epidemic for urgent research and development before and during an epidemic towards diagnostic tests, vaccines and medicines. The prediction came to pass with the COVID-19 pandemic.
  • 1.1K
  • 12 Oct 2022
Topic Review
Sky Angel
Sky Angel was a U.S. operator of Christian television networks; it operated three channels, Angel One, Angel Two, and KTV, all of which were exclusive to Dish Network. The company's corporate headquarters were located in Naples, Florida. The company also operated a Chattanooga, Tennessee location where programming, engineering and network operations resided. The company previously operated as a Christian-oriented television provider carrying religious and family-oriented programming, first as a satellite television service, and later as an over-the-top internet television provider. The shift to an IPTV platform was later accompanied by the spin-off of the provider's secular offerings into a second service known as FAVE TV. On January 14, 2014, Sky Angel ceased its IPTV business, citing that because it did not fall under the traditional legal definition of a multichannel video programming distributor, it was unable to employ legal remedies for its allegations that broadcasters were discriminating against its business model by preventing carriage of their channels.
  • 2.0K
  • 12 Oct 2022
Topic Review
Forensic Statistics
Forensic statistics is the application of probability models and statistical techniques to scientific evidence, such as DNA evidence, and the law. In contrast to "everyday" statistics, to not engender bias or unduly draw conclusions, forensic statisticians report likelihoods as likelihood ratios (LR). This ratio of probabilities is then used by juries or judges to draw inferences or conclusions and decide legal matters. Jurors and judges rely on the strength of a DNA match, given by statistics, to make conclusions and determine guilt or innocence in legal matters. In forensic science, the DNA evidence received for DNA profiling often contains a mixture of more than one person's DNA. DNA profiles are generated using a set procedure, however, the interpretation of a DNA profile becomes more complicated when the sample contains a mixture of DNA. Regardless of the number of contributors to the forensic sample, statistics and probabilities must be used to provide weight to the evidence and to describe what the results of the DNA evidence mean. In a single-source DNA profile, the statistic used is termed a random match probability (RMP). RMPs can also be used in certain situations to describe the results of the interpretation of a DNA mixture. Other statistical tools to describe DNA mixture profiles include likelihood ratios (LR) and combined probability of inclusion (CPI), also known as random man not excluded (RMNE). Computer programs have been implemented with forensic DNA statistics for assessing the biological relationships between two or more people. Forensic science uses several approaches for DNA statistics with computer programs such as; match probability, exclusion probability, likelihood ratios, Bayesian approaches, and paternity and kinship testing. Although the precise origin of this term remains unclear, it is apparent that the term was used in the 1980s and 1990s. Among the first forensic statistics conferences were two held in 1991 and 1993.
  • 3.2K
  • 12 Oct 2022
Topic Review
Yield (Engineering)
In materials science and engineering, the yield point is the point on a stress-strain curve that indicates the limit of elastic behavior and the beginning of plastic behavior. Below the yield point, a material will deform elastically and will return to its original shape when the applied stress is removed. Once the yield point is passed, some fraction of the deformation will be permanent and non-reversible and is known as plastic deformation. The yield strength or yield stress is a material property and is the stress corresponding to the yield point at which the material begins to deform plastically. The yield strength is often used to determine the maximum allowable load in a mechanical component, since it represents the upper limit to forces that can be applied without producing permanent deformation. In some materials, such as aluminium, there is a gradual onset of non-linear behavior, making the precise yield point difficult to determine. In such a case, the offset yield point (or proof stress) is taken as the stress at which 0.2% plastic deformation occurs. Yielding is a gradual failure mode which is normally not catastrophic, unlike ultimate failure. In solid mechanics, the yield point can be specified in terms of the three-dimensional principal stresses ([math]\displaystyle{ \sigma_1, \sigma_2 , \sigma_3 }[/math]) with a yield surface or a yield criterion. A variety of yield criteria have been developed for different materials.
  • 4.5K
  • 17 Oct 2022
Topic Review
September 2019 Climate Strikes
The September 2019 climate strikes, also known as the Global Week for Future, were a series of international strikes and protests to demand action be taken to address climate change, which took place from 20–27 September. The strikes' key dates were 20 September, which was three days before the United Nations Climate Summit, and 27 September. The protests took place across 4,500 locations in 150 countries. The event is a part of the school strike for climate movement, inspired by Swedish climate activist Greta Thunberg. The Guardian reported that roughly 6 million people participated in the events, whilst 350.org—a group that organised many of the protests—claim that 7.6 million people participated. The 20 September protests were likely the largest climate strikes in world history. Organisers reported that over 4 million people participated in strikes worldwide, including 1.4 million participants in Germany. An estimated 300,000 protesters took part in Australian strikes, a further 300,000 people joined UK protests and protesters in New York—where Greta Thunberg delivered a speech—numbered roughly 250,000. More than 2,000 scientists in 40 countries pledged to support the strikes. A second wave of protests took place on 27 September, in which an estimated 2 million people took part in over 2,400 protests. There were reported figures of one million protesters in Italy, and 170,000 people in New Zealand. In Montreal, where Greta Thunberg spoke, the Montreal school board cancelled classes for 114,000 of its students. Hundreds of thousands of people, including several federal party leaders, joined the march in Montreal.
  • 2.8K
  • 13 Oct 2022
Topic Review
Sleep Spindle
Sleep spindles are bursts of neural oscillatory activity that are generated by interplay of the thalamic reticular nucleus (TRN) and other thalamic nuclei during stage 2 NREM sleep in a frequency of ~10 –12 Hz for at least 0.5 seconds. After generation in the TRN, spindles are sustained and relayed to the cortex by a thalamo-thalamic and thalamo-cortical feedback loops regulated by both GABAergic and NMDA-receptor mediated glutamatergic neurotransmission. Sleep spindles have been found in all tested mammalian species and in vitro cells. Research supports that spindles (sometimes referred to as "sigma bands" or "sigma waves") play an essential role in both sensory processing and long term memory consolidation. Until recently, it was believed that each sleep spindle oscillation peaked at the same time throughout the neocortex. It was determined that oscillations sweep across the neocortex in circular patterns around the neocortex, peaking in one area, and then a few milliseconds later in an adjacent area. It has been suggested that this spindle organization allows for neurons to communicate across cortices. The time scale at which the waves travel at is the same speed it takes for neurons to communicate with each other.
  • 973
  • 12 Oct 2022
  • Page
  • of
  • 863

Other Entry Collections

>>