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🔗 Albert Stevens

🔗 Biography

Albert Stevens (1887–1966), also known as patient CAL-1, was a victim of a human radiation experiment, and survived the highest known accumulated radiation dose in any human. On May 14, 1945, he was injected with 131 kBq (3.55 µCi) of plutonium without his knowledge or informed consent.

Plutonium remained present in his body for the remainder of his life, the amount decaying slowly through radioactive decay and biological elimination. Stevens died of heart disease some 20 years later, having accumulated an effective radiation dose of 64 Sv (6400 rem) over that period, i.e. an average of 3 Sv per year or 350 μSv/h. The current annual permitted dose for a radiation worker in the United States is 0.05 Sv (or 5 rem), i.e. an average of 5.7 μSv/h.

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🔗 Levenshtein Distance

🔗 Computer science

In information theory, linguistics and computer science, the Levenshtein distance is a string metric for measuring the difference between two sequences. Informally, the Levenshtein distance between two words is the minimum number of single-character edits (insertions, deletions or substitutions) required to change one word into the other. It is named after the Soviet mathematician Vladimir Levenshtein, who considered this distance in 1965.

Levenshtein distance may also be referred to as edit distance, although that term may also denote a larger family of distance metrics known collectively as edit distance. It is closely related to pairwise string alignments.

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🔗 Sputnik virophage

🔗 Viruses

Sputnik virophage (from Russian cпутник "satellite", Latin "virus" and Greek φάγειν phagein "to eat") is a subviral agent that reproduces in amoeba cells that are already infected by a certain helper virus; Sputnik uses the helper virus's machinery for reproduction and inhibits replication of the helper virus.

Viruses like Sputnik that depend on co-infection of the host cell by helper viruses are known as satellite viruses. At its discovery in a Paris water-cooling tower in 2008 Sputnik was the first known satellite virus that inhibited replication of its helper virus and thus acted as a parasite of that virus. In analogy to the term bacteriophage it was called a virophage. However, the usage of this term and the relationship between virophages and classical satellite viruses remain controversial.

Sputnik virophages were found infecting giant viruses of Mimiviridae group A. However, they are able to grow in amoebae infected by Mimiviridae of any of the groups A, B, and C.

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🔗 The Great Debate

🔗 Astronomy

The Great Debate, also called the Shapley–Curtis Debate, was held on 26 April 1920 at the Smithsonian Museum of Natural History, between the astronomers Harlow Shapley and Heber Curtis. It concerned the nature of so-called spiral nebulae and the size of the universe; Shapley believed that distant nebulae were relatively small and lay within the outskirts of Earth's home galaxy, while Curtis held that they were in fact independent galaxies, implying that they were exceedingly large and distant.

The two scientists first presented independent technical papers about "The Scale of the Universe" during the day and then took part in a joint discussion that evening. Much of the lore of the Great Debate grew out of two papers published by Shapley and by Curtis in the May 1921 issue of the Bulletin of the National Research Council. The published papers each included counter arguments to the position advocated by the other scientist at the 1920 meeting.

In the aftermath of the public debate, scientists have been able to verify individual pieces of evidence from both astronomers, but on the main point of the existence of other galaxies, Curtis has been proven correct.

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🔗 The Overview Effect

🔗 Spaceflight 🔗 Psychology 🔗 Spirituality

The overview effect is a cognitive shift in awareness reported by some astronauts during spaceflight, often while viewing the Earth from outer space.

It is the experience of seeing firsthand the reality of the Earth in space, which is immediately understood to be a tiny, fragile ball of life, "hanging in the void", shielded and nourished by a paper-thin atmosphere. From space, national boundaries vanish, the conflicts that divide people become less important, and the need to create a planetary society with the united will to protect this "pale blue dot" becomes both obvious and imperative.

The thing that really surprised me was that it [Earth] projected an air of fragility. And why, I don’t know. I don’t know to this day. I had a feeling it’s tiny, it’s shiny, it’s beautiful, it’s home, and it’s fragile.

Astronauts Michael Collins, Ron Garan, Rusty Schweikart, Edgar Mitchell, Tom Jones, Scott Kelly, James Irwin, Mike Massimino, André Kuipers, Chris Hadfield, and Sally Ride are all reported to have experienced the effect.

The term and concept were coined in 1987 by Frank White, who explored the theme in his book The Overview Effect — Space Exploration and Human Evolution (Houghton-Mifflin, 1987), (AIAA, 1998).

In 2018, the SpaceBuzz project was created so "children around the world can also get to experience the Overview Effect." It was announced in a press release on December 20 by astronaut André Kuipers on the European Space Agency's (ESA) website. Spacebuzz aims to give children an overview effect like experience using virtual reality (VR) in order to have the same insight astronauts have when seeing planet Earth from space. Spacebuzz is a project started by the Overview Effect Foundation backed by ESA and the Netherlands Space Office..

In late 2019 it was reported that researchers at the University of Missouri aimed to reproduce the experience, with an isolation tank, half a tonne of Epsom salts, and a waterproof VR headset.

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🔗 Chorded keyboard

🔗 Computing 🔗 Computing/Computer hardware 🔗 Occupational Safety and Health 🔗 Typography

A keyset or chorded keyboard (also called a chorded keyset, chord keyboard or chording keyboard) is a computer input device that allows the user to enter characters or commands formed by pressing several keys together, like playing a "chord" on a piano. The large number of combinations available from a small number of keys allows text or commands to be entered with one hand, leaving the other hand free. A secondary advantage is that it can be built into a device (such as a pocket-sized computer or a bicycle handlebar) that is too small to contain a normal-sized keyboard.

A chorded keyboard minus the board, typically designed to be used while held in the hand, is called a keyer. Douglas Engelbart introduced the chorded keyset as a computer interface in 1968 at what is often called "The Mother of All Demos".

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🔗 Deep Operation

🔗 Soviet Union 🔗 Military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/World War II 🔗 Military history/Russian, Soviet and CIS military history

Deep operation (Russian: Глубокая операция, glubokaya operatsiya), also known as Soviet Deep Battle, was a military theory developed by the Soviet Union for its armed forces during the 1920s and 1930s. It was a tenet that emphasized destroying, suppressing or disorganizing enemy forces not only at the line of contact, but throughout the depth of the battlefield.

The term comes from Vladimir Triandafillov, an influential military writer, who worked with others to create a military strategy with its own specialized operational art and tactics. The concept of deep operations was a national strategy, tailored to the economic, cultural and geopolitical position of the Soviet Union. In the aftermath of several failures or defeats in the Russo-Japanese War, First World War and Polish–Soviet War, the Soviet High Command (Stavka) focused on developing new methods for the conduct of war. This new approach considered military strategy and tactics, but also introduced a new intermediate level of military art: operations. The Soviet Union was the first country to officially distinguish the third level of military thinking which occupied the position between strategy and tactics.

Using these templates, the Soviets developed the concept of deep battle and by 1936 it had become part of the Red Army Field Regulations. Deep operations had two phases: the tactical deep battle, followed by the exploitation of tactical success, known as the conduct of deep battle operations. Deep battle envisaged the breaking of the enemy's forward defenses, or tactical zones, through combined arms assaults, which would be followed up by fresh uncommitted mobile operational reserves sent to exploit the strategic depth of an enemy front. The goal of a deep operation was to inflict a decisive strategic defeat on the enemy's logistical abilities and render the defence of their front more difficult, impossible—or, indeed, irrelevant. Unlike most other doctrines, deep battle stressed combined arms cooperation at all levels: strategic, operational, and tactical.

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🔗 Kayfabe

🔗 Linguistics 🔗 Professional wrestling

In professional wrestling, kayfabe (also called work or worked) is the portrayal of staged events within the industry as "real" or "true", specifically the portrayal of competition, rivalries, and relationships between participants as being genuine and not of a staged or predetermined nature of any kind. The term kayfabe has evolved to also become a code word of sorts for maintaining this "reality" within the direct or indirect presence of the general public.

Kayfabe is often seen as the suspension of disbelief that is used to create the non-wrestling aspects of promotions, such as feuds, angles, and gimmicks in a manner similar to other forms of fictional entertainment. In relative terms, a wrestler breaking kayfabe during a show would be likened to an actor breaking character on-camera. Also, since wrestling is performed in front of a live audience, whose interaction with the show is crucial to its success, kayfabe can be compared to the fourth wall in acting, since hardly any conventional fourth wall exists to begin with. In general, everything in a professional wrestling show is to some extent scripted, or "kayfabe", even though at times it is portrayed as real-life.

Kayfabe was fiercely maintained for decades, but with the advent of the Internet wrestling community, and the sports entertainment movement, the pro wrestling industry has become less concerned with protecting so-called backstage secrets and typically maintains kayfabe only during the shows. Kayfabe is, however, occasionally broken during shows, usually when dealing with genuine injuries during a match or paying tribute to wrestlers.

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🔗 The Invincible – 1964 novel

🔗 Novels 🔗 Novels/Science fiction

The Invincible (Polish: Niezwyciężony) is a hard science fiction novel by Polish writer Stanisław Lem, published in 1964.

The Invincible originally appeared as the title story in Lem's collection Niezwyciężony i inne opowiadania ("The Invincible and Other Stories"). A translation into German was published in 1967; an English translation by Wendayne Ackerman, based on the German one, was published in 1973. A direct translation into English from Polish, by Bill Johnston, was published in 2006.

It was one of the first novels to explore the ideas of microrobots/smartdust/etc., artificial swarm intelligence and "necroevolution", a term suggested by Lem for evolution of non-living matter.

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🔗 Giffard Dirigible

🔗 Aviation 🔗 Aviation/aircraft

The Giffard dirigible or Giffard airship was an airship built in France in 1852 by Henri Giffard, the first powered and steerable (French: dirigeable – "directable") airship to fly. The craft featured an elongated hydrogen-filled envelope that tapered to a point at each end. From this was suspended a long beam with a triangular, sail-like rudder at its aft end, and beneath the beam a platform for the pilot and steam engine. Due to the highly flammable nature of the lift gas, special precautions were taken to minimise the potential for the envelope to be ignited by the engine beneath it. The engine's exhaust was diverted downwards to a long pipe projecting below the platform, and the area surrounding the boiler's stoke hole was surrounded by wire gauze. On 24 September 1852, Giffard flew the airship from the hippodrome at Place de l'Etoile to Élancourt, covering the 27 km (17 mi) in around 3 hours, demonstrating maneuvering along the way. The engine, however, was not sufficiently powerful to allow Giffard to fly against the wind to make a return journey.