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🔗 Original Antigenic Sin
Original antigenic sin, also known as antigenic imprinting or the Hoskins effect, refers to the propensity of the body's immune system to preferentially utilize immunological memory based on a previous infection when a second slightly different version of that foreign pathogen (e.g. a virus or bacterium) is encountered. This leaves the immune system "trapped" by the first response it has made to each antigen, and unable to mount potentially more effective responses during subsequent infections. Antibodies or T-cells induced during infections with the first variant of the pathogen are subject to a form of original antigenic sin, termed repertoire freeze.
The phenomenon of original antigenic sin has been described in relation to influenza virus, dengue fever, human immunodeficiency virus (HIV) and to several other viruses.
This phenomenon was first described in 1960 by Thomas Francis Jr. in the article "On the Doctrine of Original Antigenic Sin". It is named by analogy to the theological concept of original sin. According to Francis as cited by Richard Krause:
"The antibody of childhood is largely a response to dominant antigen of the virus causing the first type A influenza infection of the lifetime. [...] The imprint established by the original virus infection governs the antibody response thereafter. This we have called the Doctrine of the Original Antigenic Sin."
🔗 Bruno Pontecorvo
Bruno Pontecorvo (Italian: [ponteˈkɔrvo]; Russian: Бру́но Макси́мович Понтеко́рво, Bruno Maksimovich Pontecorvo; 22 August 1913 – 24 September 1993) was an Italian and Soviet nuclear physicist, an early assistant of Enrico Fermi and the author of numerous studies in high energy physics, especially on neutrinos. A convinced communist, he defected to the Soviet Union in 1950, where he continued his research on the decay of the muon and on neutrinos. The prestigious Pontecorvo Prize was instituted in his memory in 1995.
The fourth of eight children of a wealthy Jewish-Italian family, Pontecorvo studied physics at the University of Rome La Sapienza, under Fermi, becoming the youngest of his Via Panisperna boys. In 1934 he participated in Fermi's famous experiment showing the properties of slow neutrons that led the way to the discovery of nuclear fission. He moved to Paris in 1934, where he conducted research under Irène and Frédéric Joliot-Curie. Influenced by his cousin, Emilio Sereni, he joined the French Communist Party, as did his sisters Giuliana and Laura and brother Gillo. The Italian Fascist regime's 1938 racial laws against Jews caused his family members to leave Italy for Britain, France and the United States.
When the German Army closed in on Paris during the Second World War, Pontecorvo, his brother Gillo, cousin Emilio Sereni and Salvador Luria fled the city on bicycles. He eventually made his way to Tulsa, Oklahoma, where he applied his knowledge of nuclear physics to prospecting for oil and minerals. In 1943, he joined the British Tube Alloys team at the Montreal Laboratory in Canada. This became part of the Manhattan Project to develop the first atomic bombs. At Chalk River Laboratories, he worked on the design of the nuclear reactor ZEEP, the first reactor outside of the United States that went critical in 1945, followed by the NRX reactor in 1947. He also looked into cosmic rays, the decay of muons, and what would become his obsession, neutrinos. He moved to Britain in 1949, where he worked for the Atomic Energy Research Establishment at Harwell.
After his defection to the Soviet Union in 1950, he worked at the Joint Institute for Nuclear Research (JINR) in Dubna. He had proposed using chlorine to detect neutrinos. In a 1959 paper, he argued that the electron neutrino (
ν
e) and the muon neutrino (
ν
μ) were different particles. Solar neutrinos were detected by the Homestake Experiment, but only between one third and one half of the predicted number were found. In response to this solar neutrino problem, he proposed a phenomenon known as neutrino oscillation, whereby electron neutrinos became muon neutrinos. The existence of the oscillations was finally established by the Super-Kamiokande experiment in 1998. He also predicted in 1958 that supernovae would produce intense bursts of neutrinos, which was confirmed in 1987 when Supernova SN1987A was detected by neutrino detectors.
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- "Bruno Pontecorvo" | 2021-10-27 | 13 Upvotes 4 Comments
🔗 Retrieve a random Wikipedia page
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- "Longest Wikipedia Pages" | 2022-03-25 | 10 Upvotes 3 Comments
- "Retrieve a random Wikipedia page" | 2021-10-26 | 19 Upvotes 13 Comments
🔗 Ephemeralization
Ephemeralization, a term coined by R. Buckminster Fuller in 1938, is the ability of technological advancement to do "more and more with less and less until eventually you can do everything with nothing," that is, an accelerating increase in the efficiency of achieving the same or more output (products, services, information, etc.) while requiring less input (effort, time, resources, etc.). Fuller's vision was that ephemeralization will result in ever-increasing standards of living for an ever-growing population despite finite resources. The concept has been embraced by those who argue against Malthusian philosophy. The subsequently coined economics term "dematerialization" refers to essentially the same concept as also does eco-economic decoupling.
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- "Ephemeralization" | 2021-10-25 | 146 Upvotes 68 Comments
🔗 Intelink
Intelink is a group of secure intranets used by the United States Intelligence Community. The first Intelink network was established in 1994 to take advantage of Internet technologies (though not connected to the public Internet) and services to promote intelligence dissemination and business workflow. Since then it has become an essential capability for the US intelligence community and its partners to share information, collaborate across agencies, and conduct business. Intelink refers to the web environment on protected top secret, secret, and unclassified networks. One of the key features of Intelink is Intellipedia, an online system for collaborative data sharing based on MediaWiki. Intelink uses WordPress as the basis of its blogging service.
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- "Intelink" | 2021-10-25 | 53 Upvotes 11 Comments
🔗 Signal for Help
The Signal for Help (or the Violence at Home Signal for Help) is a single-handed gesture that can be used by an individual to alert others that they feel threatened and need help over a video call, or in-person. It was originally created as a tool to combat the rise in domestic violence cases around the world as a result of the self-isolation measures related to the COVID-19 pandemic.
The signal is performed by holding one hand up with the thumb tucked into the palm, then folding the four other fingers down, symbolically trapping the thumb in the rest of the fingers. It was intentionally designed as a single continuous hand movement, rather than a sign held in one position, that could be made easily visible.
The Signal for Help was first introduced in Canada by the Canadian Women's Foundation on April 14, 2020, and on April 28, 2020 in the United States by the Women's Funding Network (WFN). It received widespread praise from local, national, and international news organizations for helping provide a modern solution to the issue of a rise in domestic violence cases.
Addressing concerns that abusers may become aware of such a widespread online initiative, the Canadian Women's Foundation and other organizations clarified that this signal is not "something that's going to save the day," but rather a tool someone could use to get help.
Instructions for what to do if an individual sees the signal, and how to check-in safely, were also created.
Discussed on
- "Signal for Help" | 2021-10-24 | 231 Upvotes 98 Comments
🔗 Jesuit Reduction
The Jesuit reductions were a type of settlement for indigenous people specifically in the Rio Grande do Sul area of Brazil, Paraguay and neighbouring Argentina in South America, established by the Jesuit Order early in the 17th century and wound up in the 18th century with the banning of the Jesuit order in several European countries. Subsequently, it has been called an experiment in "socialist theocracy" or a rare example of "benign colonialism".
In their newly acquired South American dominions, the Spanish and Portuguese Empires had adopted a strategy of gathering native populations into communities called "Indian reductions" (Spanish: reducciones de indios) and Portuguese: redução (plural reduções). The objectives of the reductions were to impart Christianity and European culture. Secular as well as religious authorities created "reductions".
The Jesuit reductions were Christian missions that extended successfully in an area straddling the borders of present-day Paraguay, Brazil, and Argentina (the triple frontera) amongst the Guaraní peoples. The reductions are often called collectively the Río de la Plata missions. The Jesuits attempted to create a "state within a state" in which the native peoples in the reductions, guided by the Jesuits, would remain autonomous and isolated from Spanish colonists and Spanish rule. A major factor attracting the natives to the reductions was the protection they afforded from enslavement and the forced labour of encomiendas.
Under the leadership of both the Jesuits and native caciques, the reductions achieved a high degree of autonomy within the Spanish colonial empire. With the use of native labour, the reductions became economically successful. When the incursions of Brazilian Bandeirante slave-traders threatened the existence of the reductions, Indian militias were set up, which fought effectively against the Portuguese colonists. However, directly as a result of the Suppression of the Society of Jesus in several European countries, including Spain, in 1767, the Jesuits were expelled from the Guaraní missions (and the Americas) by order of the Spanish king, Charles III. So ended the era of the Paraguayan reductions. The reasons for the expulsion related more to politics in Europe than the activities of the Jesuit missions themselves.
The Jesuit Rio de la Plata reductions reached a maximum population of 141,182 in 1732 in 30 missions in Brazil, Paraguay, and Argentina. The reductions of the Jesuit Missions of Chiquitos in eastern Bolivia reached a maximum population of 25,000 in 1766. Jesuit reductions in the Llanos de Moxos, also in Bolivia, reached a population of about 30,000 in 1720. In Chiquitos, the first reduction was founded in 1691 and in the Llanos de Moxos in 1682.
The Jesuit reductions have been lavishly praised as a "socialist utopia" and a "Christian communistic republic" as well as criticized for their "rigid, severe and meticulous regimentation" of the lives of the Indian people they ruled with a firm hand through Guaraní intermediaries.
Discussed on
- "Jesuit Reduction" | 2021-10-22 | 13 Upvotes 1 Comments
🔗 Wall of Sound
The Wall of Sound (also called the Spector Sound) is a music production formula developed by American record producer Phil Spector at Gold Star Studios, in the 1960s, with assistance from engineer Larry Levine and the conglomerate of session musicians later known as "the Wrecking Crew". The intention was to exploit the possibilities of studio recording to create an unusually dense orchestral aesthetic that came across well through radios and jukeboxes of the era. Spector explained in 1964: "I was looking for a sound, a sound so strong that if the material was not the greatest, the sound would carry the record. It was a case of augmenting, augmenting. It all fit together like a jigsaw."
A popular misconception holds that the Wall of Sound was created simply through a maximum of noise and distortion, but the method was actually more nuanced. To attain the Wall of Sound, Spector's arrangements called for large ensembles (including some instruments not generally used for ensemble playing, such as electric and acoustic guitars), with multiple instruments doubling or tripling many of the parts to create a fuller, richer tone. For example, Spector often duplicated a part played by an acoustic piano with an electric piano and a harpsichord. Mixed well enough, the three instruments would then be indistinguishable to the listener.
Among other features of the sound, Spector incorporated an array of orchestral instruments (strings, woodwind, brass and percussion) not previously associated with youth-oriented pop music. Reverb from an echo chamber was also highlighted for additional texture. He characterized his methods as "a Wagnerian approach to rock & roll: little symphonies for the kids". The combination of large ensembles with reverberation effects also increased the average audio power in a way that resembles compression. By 1979, the use of compression had become common on the radio, marking the trend that led to the loudness war in the 1980s.
The intricacies of the technique were unprecedented in the field of sound production for popular music. According to Beach Boys leader Brian Wilson, who used the formula extensively: "In the '40s and '50s, arrangements were considered 'OK here, listen to that French horn' or 'listen to this string section now.' It was all a definite sound. There weren't combinations of sound and, with the advent of Phil Spector, we find sound combinations, which—scientifically speaking—is a brilliant aspect of sound production."
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- "Wall of Sound" | 2021-10-22 | 69 Upvotes 50 Comments
🔗 Mulford Act
The Mulford Act was a 1967 California bill that repealed a law allowing public carrying of loaded firearms. Named after Republican assemblyman Don Mulford, and signed into law by governor of California Ronald Reagan, the bill was crafted with the goal of disarming members of the Black Panther Party who were conducting armed patrols of Oakland neighborhoods, in what would later be termed copwatching. They garnered national attention after Black Panthers members, bearing arms, marched upon the California State Capitol to protest the bill.
Assembly Bill 1591 was introduced by Don Mulford (R) from Oakland on April 5, 1967, and subsequently co-sponsored by John T. Knox (D) from Richmond, Walter J. Karabian (D) from Monterey Park, Frank Murphy Jr. (R) from Santa Cruz, Alan Sieroty (D) from Los Angeles, and William M. Ketchum (R) from Bakersfield. AB-1591 was made an “urgency statute” under Article IV, §8(d) of the Constitution of California after “an organized band of men armed with loaded firearms [...] entered the Capitol” on May 2, 1967; as such, it required a 2/3 majority in each house. It passed the Assembly (controlled by Democrats, 42:38) at subsequent readings, passed the Senate (controlled by Democrats, 20:19) on July 26 by 29 votes to 7, and was signed by Governor Ronald Reagan on July 28, 1967. The law banned the carrying of loaded weapons in public.
Both Republicans and Democrats in California supported increased gun control, as did the National Rifle Association of America. Governor Ronald Reagan, who was coincidentally present on the capitol lawn when the protesters arrived, later commented that he saw "no reason why on the street today a citizen should be carrying loaded weapons" and that guns were a "ridiculous way to solve problems that have to be solved among people of good will." In a later press conference, Reagan added that the Mulford Act "would work no hardship on the honest citizen."
The bill was signed by Reagan and became California penal code 25850 and 171c.
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- "Mulford Act" | 2021-10-20 | 17 Upvotes 3 Comments
🔗 Umbral Calculus
In mathematics before the 1970s, the term umbral calculus referred to the surprising similarity between seemingly unrelated polynomial equations and certain "shadowy" techniques used to "prove" them. These techniques were introduced by John Blissard (1861) and are sometimes called Blissard's symbolic method. They are often attributed to Édouard Lucas (or James Joseph Sylvester), who used the technique extensively.