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πŸ”— Belyayev's Fox Experiment

πŸ”— Biography πŸ”— Soviet Union πŸ”— Russia πŸ”— Biology πŸ”— Biography/science and academia πŸ”— Russia/science and education in Russia πŸ”— Genetics πŸ”— Russia/physical geography of Russia

Dmitry Konstantinovich Belyayev (Russian: Дми́трий ΠšΠΎΠ½ΡΡ‚Π°Π½Ρ‚ΠΈΜΠ½ΠΎΠ²ΠΈΡ‡ БСля́Св, 17 July 1917 – 14 November 1985) was a Russian geneticist and academician who served as director of the Institute of Cytology and Genetics (IC&G) of the USSR Academy of Sciences, Novosibirsk, from 1959 to 1985. His decades-long effort to breed domesticated foxes was described by The New York Times as β€œarguably the most extraordinary breeding experiment ever conducted.” A 2010 article in Scientific American stated that Belyayev β€œmay be the man most responsible for our understanding of the process by which wolves were domesticated into our canine companions.”

Beginning in the 1950s, in order to uncover the genetic basis of the distinctive behavioral and physiological attributes of domesticated animals, Belyayev and his team spent decades breeding the wild silver fox (Vulpes vulpes) and selecting for reproduction only those individuals in each generation that showed the least fear of humans. After several generations of controlled breeding, a majority of the silver foxes no longer showed any fear of humans and often wagged their tails and licked their human caretakers to show affection. They also began to display spotted coats, floppy ears, curled tails, as well as other physical attributes often found in domesticated animals, thus confirming Belyayev’s hypothesis that both the behavioral and physical traits of domesticated animals could be traced to "a collection of genes that conferred a propensity to tamenessβ€”a genotype that the foxes perhaps shared with any species that could be domesticated".

Belyayev’s experiments were the result of a politically motivated demotion, in response to defying the now discredited non-Mendellian theories of Lysenkoism, which were politically accepted in the Soviet Union at the time. Belyayev has since been vindicated in recent years by major scientific journals, and by the Soviet establishment as a pioneering figure in modern genetics.

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πŸ”— Unidirectional Network

A unidirectional network (also referred to as a unidirectional gateway or data diode) is a network appliance or device that allows data to travel in only one direction. Data diodes can be found most commonly in high security environments, such as defense, where they serve as connections between two or more networks of differing security classifications. Given the rise of industrial IoT and digitization, this technology can now be found at the industrial control level for such facilities as nuclear power plants, power generation and safety critical systems like railway networks.

After years of development the use of data diodes have increased creating two variations:

  • Data diode: Network appliance or device allowing raw data to travel only in one direction, used in guaranteeing information security or protection of critical digital systems, such as industrial control systems, from inbound cyber attacks.
  • Unidirectional gateway: Combination of hardware and software running in proxy computers in the source and destination networks. The hardware, a data diode, enforces physical unidirectionality and the software replicates databases and emulates protocol servers to handle bi-directional communication. The unidirectional gateway is capable of transferring multiple protocols and data types simultaneously. It contains a broader range of cybersecurity features like, secure boot, certificate management, data integrity, forward error correction (FEC), secure communication via TLS, among others. A unique characteristic is that data is transferred deterministically (to predetermined locations) with a protocol "break" that allows the data to be transferred through the data diode.

Data diodes are commonly found in high security military and government environments, and are now becoming widely spread in sectors like oil & gas, water/wastewater, airplanes (between flight control units and in-flight entertainment systems), manufacturing and cloud connectivity for industrial IoT. New regulations have increased demand and with increased capacity, major technology vendors have lowered the cost of the core technology.

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πŸ”— The Schmidt insect sting pain index

πŸ”— Medicine πŸ”— Agriculture πŸ”— Insects πŸ”— Insects/Ant πŸ”— Agriculture/Beekeeping πŸ”— Insects/Hymenoptera

The Schmidt sting pain index is a pain scale rating the relative pain caused by different hymenopteran stings. It is mainly the work of Justin O. Schmidt (born 1947), an entomologist at the Carl Hayden Bee Research Center in Arizona, United States. Schmidt has published a number of papers on the subject, and claims to have been stung by the majority of stinging Hymenoptera.

His original paper in 1983 was a way to systematize and compare the hemolytic properties of insect venoms. A table contained in the paper included a column that rated sting pain, starting from 0 for stings that are completely ineffective against humans, progressing through 2, a familiar pain such as that caused by a common bee or wasp sting, and finishing at 4 for the most painful stings; in the original paper, only the bullet ant, Paraponera clavata, was given a rating of 4. Later revised versions of the index added Synoeca septentrionalis, along with tarantula hawks as the only species to share this ranking. In later versions, some descriptions of the most painful examples were given, e.g.: "Paraponera clavata stings induced immediate, excruciating pain and numbness to pencil-point pressure, as well as trembling in the form of a totally uncontrollable urge to shake the affected part."

Schmidt has repeatedly refined his scale, including a paper published in 1990, which classifies the stings of 78 species and 41 genera of Hymenoptera, and culminating in a book published in 2016.

An entry in The Straight Dope reported that "implausibly exact numbers" which do not appear in any of Schmidt’s published scientific papers were "wheedled out of him" by Outside magazine for an article it published in 1996.

In September 2015, Schmidt was co-awarded the Ig Nobel Physiology and Entomology prize with Michael Smith for their Hymenoptera research.

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πŸ”— Great Woman of Mathematics: Marie-Sophie Germain, 1776-1831

πŸ”— Biography πŸ”— Mathematics πŸ”— France πŸ”— Women scientists πŸ”— Biography/science and academia πŸ”— Women's History πŸ”— Mathematics/Mathematicians

Marie-Sophie Germain (French:Β [maʁi sΙ”fi ʒɛʁmΙ›Μƒ]; 1 April 1776 – 27 June 1831) was a French mathematician, physicist, and philosopher. Despite initial opposition from her parents and difficulties presented by society, she gained education from books in her father's library, including ones by Leonhard Euler, and from correspondence with famous mathematicians such as Lagrange, Legendre, and Gauss (under the pseudonym of Β«Monsieur LeBlancΒ»). One of the pioneers of elasticity theory, she won the grand prize from the Paris Academy of Sciences for her essay on the subject. Her work on Fermat's Last Theorem provided a foundation for mathematicians exploring the subject for hundreds of years after. Because of prejudice against her sex, she was unable to make a career out of mathematics, but she worked independently throughout her life. Before her death, Gauss had recommended that she be awarded an honorary degree, but that never occurred. On 27 June 1831, she died from breast cancer. At the centenary of her life, a street and a girls’ school were named after her. The Academy of Sciences established the Sophie Germain Prize in her honor.

πŸ”— Balloonomania

πŸ”— Aviation

Balloonomania was a strong public interest or fad in balloons that originated in France in the late 18th century and continued into the 19th century, during the advent of balloon flights. The interest began with the first flights of the Montgolfier brothers in 1783 (in a balloon inflated with hot air). Soon afterwards Jacques Alexandre CΓ©sar Charles flew another type of balloon (inflated with hydrogen) and both types of balloon were in use from then on. The fad quickly spread in France and across the channel in England.

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πŸ”— Mental poker

Mental poker is the common name for a set of cryptographic problems that concerns playing a fair game over distance without the need for a trusted third party. The term is also applied to the theories surrounding these problems and their possible solutions. The name comes from the card game poker which is one of the games to which this kind of problem applies. Similar problems described as two party games are Blum's flipping a coin over a distance, Yao's Millionaires' Problem, and Rabin's oblivious transfer.

The problem can be described thus: "How can one allow only authorized actors to have access to certain information while not using a trusted arbiter?" (Eliminating the trusted third-party avoids the problem of trying to determine whether the third party can be trusted or not, and may also reduce the resources required.)

In poker, this could translate to: "How can we make sure no player is stacking the deck or peeking at other players' cards when we are shuffling the deck ourselves?". In a physical card game, this would be relatively simple if the players were sitting face to face and observing each other, at least if the possibility of conventional cheating can be ruled out. However, if the players are not sitting at the same location but instead are at widely separate locations and pass the entire deck between them (using the postal mail, for instance), this suddenly becomes very difficult. And for electronic card games, such as online poker, where the mechanics of the game are hidden from the user, this is impossible unless the method used is such that it cannot allow any party to cheat by manipulating or inappropriately observing the electronic "deck".

Several protocols for doing this have been suggested, the first by Adi Shamir, Ron Rivest and Len Adleman (the creators of the RSA-encryption protocol). This protocol was the first example of two parties conducting secure computation rather than secure message transmission, employing cryptography; later on due to leaking partial information in the original protocol, this led to the definition of semantic security by Shafi Goldwasser and Silvio Micali. The concept of multi-player mental poker was introduced in Moti Yung's 1984 book Cryptoprotocols. The area has later evolved into what is known as secure multi-party computation protocols (for two parties, and multi parties as well).

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πŸ”— Mariko Aoki Phenomenon

πŸ”— Books πŸ”— Psychology πŸ”— Japan

The Mariko Aoki phenomenon (ι’ζœ¨γΎγ‚Šγ“ηΎθ±‘, Aoki Mariko genshō) is a Japanese expression referring to an urge to defecate that is suddenly felt after entering bookstores. The phenomenon's name derives from the name of the woman who mentioned the phenomenon in a magazine article in 1985. According to Japanese social psychologist Shozo Shibuya, the specific causes that trigger a defecation urge in bookstores are not yet clearly understood (as of 2014). There are also some who are skeptical about whether such a peculiar phenomenon really exists at all, and it is sometimes discussed as one type of urban myth.

The series of processes through which being in a bookstore leads to an awareness of a defecation urge is something that cannot be explained from a medical perspective as a single pathological concept, at least at present. According to a number of discussions on the topic, even if it can be sufficiently found that this phenomenon actually exists, it is a concept that would be difficult to be deemed a specific pathological entity (such as a "Mariko Aoki disease", for example). On the other hand, it is also a fact that a considerable number of the intellectuals (particularly clinicians) who discuss this phenomenon have adopted existing medical terminology such as from diagnostics and pathology. Borrowing from this approach, this article also uses expressions from existing medical terminology for convenience.

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πŸ”— Operation Snow White

πŸ”— United States πŸ”— Espionage πŸ”— Scientology πŸ”— Crime and Criminal Biography

Operation Snow White was a criminal conspiracy by the Church of Scientology during the 1970s to purge unfavorable records about Scientology and its founder, L. Ron Hubbard. This project included a series of infiltrations into and thefts from 136 government agencies, foreign embassies and consulates, as well as private organizations critical of Scientology, carried out by Church members in more than 30 countries. It was one of the largest infiltrations of the United States government in history, with up to 5,000 covert agents. This operation also exposed the Scientology plot "Operation Freakout", because Operation Snow White was the case that initiated the U.S. government's investigation of the Church.

Under this program, Scientology operatives committed infiltration, wiretapping, and theft of documents in government offices, most notably those of the U.S. Internal Revenue Service. Eleven highly placed Church executives, including Mary Sue Hubbard (third wife of founder L. Ron Hubbard and second-in-command of the organization), pleaded guilty and were convicted in federal court of obstructing justice, burglary of government offices, and theft of documents and government property. The case was United States v. Mary Sue Hubbard et al., 493 F.Supp. 209 (D.D.C. 1979).

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πŸ”— A Tesla Valve

πŸ”— Technology

A Tesla valve, called by Tesla a valvular conduit, is a fixed-geometry passive check valve. It allows a fluid to flow preferentially in one direction, without moving parts. The device is named after Nikola Tesla, who was awarded U.S. Patent 1,329,559 in 1920 for its invention. The patent application describes the invention as follows:

The interior of the conduit is provided with enlargements, recesses, projections, baffles, or buckets which, while offering virtually no resistance to the passage of the fluid in one direction, other than surface friction, constitute an almost impassable barrier to its flow in the opposite direction.

Tesla illustrates this with the drawing, showing one possible construction with a series of eleven flow-control segments, although any other number of such segments could be used as desired to increase or decrease the flow regulation effect.

One computational fluid dynamics simulation of Tesla valves with two and four segments showed that the flow resistance in the blocking (or reverse) direction was about 15 and 40 times greater, respectively, than the unimpeded (or forward) direction. This lends support to Tesla's patent assertion that in the valvular conduit in his diagram, a pressure ratio "approximating 200 can be obtained so that the device acts as a slightly leaking valve".

The Tesla valve is used in microfluidic applications and offers advantages such as scalability, durability, and ease of fabrication in a variety of materials.

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