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πŸ”— The Butlerian Jihad

πŸ”— Novels πŸ”— Novels/Science fiction πŸ”— Science Fiction

Dune: The Butlerian Jihad is a 2002 science fiction novel by Brian Herbert and Kevin J. Anderson, set in the fictional Dune universe created by Frank Herbert. It is the first book in the Legends of Dune prequel trilogy, which takes place over 10,000 years before the events of Frank Herbert's celebrated 1965 novel Dune. The series chronicles the fictional Butlerian Jihad, a crusade by the last free humans in the universe against the thinking machines, a violent and dominating force led by the sentient computer Omnius.

Dune: The Butlerian Jihad rose to #7 on The New York Times Best Seller list in its second week of publication.

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πŸ”— Project Orion (nuclear propulsion)

πŸ”— Spaceflight

Project Orion was a study of a spacecraft intended to be directly propelled by a series of explosions of atomic bombs behind the craft (nuclear pulse propulsion). Early versions of this vehicle were proposed to take off from the ground (with significant associated nuclear fallout); later versions were presented for use only in space. Six non-nuclear tests were conducted using models. The project was eventually abandoned for multiple reasons such as the Partial Test Ban Treaty which banned nuclear explosions in space as well as concerns over nuclear fallout.

The idea of rocket propulsion by combustion of explosive substance was first proposed by Russian explosives expert Nikolai Kibalchich in 1881, and in 1891 similar ideas were developed independently by German engineer Hermann Ganswindt. Robert A. Heinlein mentions powering spaceships with nuclear bombs in his 1940 short story "Blowups Happen." Real life proposals of nuclear propulsion were first made by Stanislaw Ulam in 1946, and preliminary calculations were made by F. Reines and Ulam in a Los Alamos memorandum dated 1947. The actual project, initiated in 1958, was led by Ted Taylor at General Atomics and physicist Freeman Dyson, who at Taylor's request took a year away from the Institute for Advanced Study in Princeton to work on the project.

The Orion concept offered high thrust and high specific impulse, or propellant efficiency, at the same time. The unprecedented extreme power requirements for doing so would be met by nuclear explosions, of such power relative to the vehicle's mass as to be survived only by using external detonations without attempting to contain them in internal structures. As a qualitative comparison, traditional chemical rocketsβ€”such as the Saturn V that took the Apollo program to the Moonβ€”produce high thrust with low specific impulse, whereas electric ion engines produce a small amount of thrust very efficiently. Orion would have offered performance greater than the most advanced conventional or nuclear rocket engines then under consideration. Supporters of Project Orion felt that it had potential for cheap interplanetary travel, but it lost political approval over concerns with fallout from its propulsion.

The Partial Test Ban Treaty of 1963 is generally acknowledged to have ended the project. However, from Project Longshot to Project Daedalus, Mini-Mag Orion, and other proposals which reach engineering analysis at the level of considering thermal power dissipation, the principle of external nuclear pulse propulsion to maximize survivable power has remained common among serious concepts for interstellar flight without external power beaming and for very high-performance interplanetary flight. Such later proposals have tended to modify the basic principle by envisioning equipment driving detonation of much smaller fission or fusion pellets, in contrast to Project Orion's larger nuclear pulse units (full nuclear bombs) based on less speculative technology.

To Mars by A-Bomb: The Secret History of Project Orion was a 2003 BBC documentary film about the project.

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πŸ”— Williams syndrome

πŸ”— Medicine πŸ”— Medicine/Neurology πŸ”— Medicine/Medical genetics

Williams syndrome (WS) is a genetic disorder that affects many parts of the body. Facial features frequently include a broad forehead, short nose and full cheeks, an appearance that has been described as "elfin". While mild to moderate intellectual disability with particular problems with visual spatial tasks such as drawing is typical, verbal skills are generally relatively unaffected. Those affected often have an outgoing personality, interact readily with strangers, and appear happy. Problems with teeth, heart problems, especially supravalvular aortic stenosis, and periods of high blood calcium are common.

Williams syndrome is caused by a genetic abnormality, specifically a deletion of about 27 genes from the long arm of one of the two chromosome 7s. Typically this occurs as a random event during the formation of the egg or sperm from which a person develops. In a small number of cases, it is inherited from an affected parent in an autosomal dominant manner. The different characteristic features have been linked to the loss of specific genes. The diagnosis is typically suspected based on symptoms and confirmed by genetic testing.

Treatment includes special education programs and various types of therapy. Surgery may be done to correct heart problems. Dietary changes or medications may be required for high blood calcium. The syndrome was first described in 1961 by New Zealander John C. P. Williams. Williams syndrome affects between 1 in 7,500 to 1 in 20,000 people at birth. Life expectancy is less than that of the general population, mostly due to the increased rates of heart disease.

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πŸ”— Chrysler Turbine Car

πŸ”— Guild of Copy Editors πŸ”— Automobiles

The Chrysler Turbine Car is an experimental two-door hardtop coupe powered by a turbine engine and manufactured by Chrysler from 1963–1964. The bodywork was constructed by Italian design studio Carrozzeria Ghia and Chrysler completed the final assembly in Detroit. A total of 55 cars were manufactured: five prototypes and a limited run of 50 cars for a public user program. All have a signature metallic paint named "turbine bronze", roughly the color of root beer. The car was styled by Elwood Engel and the Chrysler studios and featured power brakes, power steering, and a TorqueFlite transmission.

The Chrysler turbine engine program that produced the Turbine Car began during the late 1930s and created prototypes that completed long-distance trips in the 1950s and early 1960s. The A-831 engines that powered the Ghia-designed Turbine Car could operate on many fuels, required less maintenance, and lasted longer than conventional piston engines, although they were much more expensive to produce.

After testing, Chrysler conducted a user program from October 1963 to January 1966 that involved 203 drivers in 133 cities in the United States cumulatively driving more than one million miles (1.6 million km). The program helped the company determine problems with the cars, notably with their complicated starting procedure, relatively unimpressive acceleration, and sub-par fuel economy and noise. The experience also revealed advantages of the turbine engines, including their remarkable durability, smooth operation, and relatively modest maintenance requirements.

After the user program ended in 1966, Chrysler reclaimed the cars and destroyed all but nine; Chrysler kept two cars, six are displayed at museums in the United States, and one is in a private collection. Chrysler's turbine engine program ended in 1979, largely due to the failure of the engines to meet government emissions regulations, relatively poor fuel economy, and as a condition of receiving a government loan in 1979.

πŸ”— American cover-up of Japanese war crimes

πŸ”— United States πŸ”— International relations πŸ”— Human rights πŸ”— Military history πŸ”— Military history/North American military history πŸ”— Military history/United States military history πŸ”— Law πŸ”— Psychology πŸ”— International relations/International law πŸ”— Sociology πŸ”— Military history/World War II πŸ”— Japan πŸ”— Japan/Japanese military history πŸ”— Military history/Asian military history πŸ”— Military history/Japanese military history πŸ”— United States/U.S. history πŸ”— Military history/Military culture, traditions, and heraldry πŸ”— Crime and Criminal Biography

The occupying United States government undertook the selective cover-up of some Japanese war crimes after the end of World War II in Asia, granting political immunity to military personnel who had engaged in human experimentation and other crimes against humanity, predominantly in mainland China. The pardon of Japanese war criminals, among whom were Unit 731's commanding officers General Shirō Ishii and General Masaji Kitano, was overseen by General of the Army Douglas MacArthur in September 1945. While a series of war tribunals and trials was organized, many of the high-ranking officials and doctors who devised and respectively performed the experiments were pardoned and never brought to justice due to the US government both classifying incriminating evidence, as well as blocking the prosecution access to key witnesses. As many as 12,000 people, most of them Chinese, died in Unit 731 alone and many more died in other facilities, such as Unit 100 and in field experiments throughout Manchuria.

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πŸ”— Erfurt Latrine Disaster of 1184

πŸ”— Germany πŸ”— Disaster management πŸ”— European history πŸ”— Royalty and Nobility πŸ”— Germany/Holy Roman Empire

In July 1184, Henry VI, King of Germany (later Holy Roman Emperor), held court at a Hoftag in the Petersberg Citadel in Erfurt. On the morning of 26 July, the combined weight of the assembled nobles caused the wooden second story floor of the building to collapse and most of them fell through into the latrine cesspit below the ground floor, where about 60 of them drowned in liquid excrement. This event is called Erfurter Latrinensturz (lit. 'Erfurt latrine fall') in several German sources.

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πŸ”— Namecoin

πŸ”— Computing πŸ”— Computing/Software πŸ”— Numismatics πŸ”— Software πŸ”— Software/Computing πŸ”— Numismatics/Cryptocurrency πŸ”— Cryptocurrency πŸ”— Computing/Computer Security

Namecoin (Symbol: β„• or NMC) is a cryptocurrency originally forked from bitcoin software. It is based on the code of bitcoin and uses the same proof-of-work algorithm. Like bitcoin, it is limited to 21 million coins.

Namecoin can store data within its own blockchain transaction database. The original proposal for Namecoin called for Namecoin to insert data into bitcoin's blockchain directly. Anticipating scaling difficulties with this approach, a shared proof-of-work (POW) system was proposed to secure new cryptocurrencies with different use cases.

Namecoin's flagship use case is the censorship-resistant top level domain .bit, which is functionally similar to .com or .net domains but is independent of ICANN, the main governing body for domain names.

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πŸ”— Hydraulic Telegraph

πŸ”— Telecommunications

A hydraulic telegraph (Greek: Ο…Ξ΄ΟΞ±Ο…Ξ»ΞΉΞΊΟŒΟ‚ τηλέγραφος) is either of two different hydraulic-telegraph telecommunication systems. The earliest one was developed in 4th-century BC Greece, while the other was developed in 19th-century AD Britain. The Greek system was deployed in combination with semaphoric fires, while the latter British system was operated purely by hydraulic fluid pressure.

Although both systems employed water in their sending and receiver devices, their transmission media were completely different. The ancient Greek system transmitted its semaphoric information to the receiver visually, which limited its use to line-of-sight distances in good visibility weather conditions only. The 19th-century British system used water-filled pipes to effect changes to the water level in the receiver unit (similar to a transparent water-filled flexible tube used as a level indicator), thus limiting its range to the hydraulic pressure that could be generated at the transmitter's device.

While the Greek device was extremely limited in the codes (and hence the information) it could convey, the British device was never deployed in operation other than for very short-distance demonstrations. Although the British device could be used in any visibility within its range of operation, it could not work in sub-zero temperatures without additional infrastructure to heat the pipes. This contributed to its impracticality.

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πŸ”— The Price of Anarchy

πŸ”— Game theory

The Price of Anarchy (PoA) is a concept in economics and game theory that measures how the efficiency of a system degrades due to selfish behavior of its agents. It is a general notion that can be extended to diverse systems and notions of efficiency. For example, consider the system of transportation of a city and many agents trying to go from some initial location to a destination. Let efficiency in this case mean the average time for an agent to reach the destination. In the 'centralized' solution, a central authority can tell each agent which path to take in order to minimize the average travel time. In the 'decentralized' version, each agent chooses its own path. The Price of Anarchy measures the ratio between average travel time in the two cases.

Usually the system is modeled as a game and the efficiency is some function of the outcomes (e.g. maximum delay in a network, congestion in a transportation system, social welfare in an auction, ...). Different concepts of equilibrium can be used to model the selfish behavior of the agents, among which the most common is the Nash equilibrium. Different flavors of Nash equilibrium lead to variations of the notion of Price of Anarchy as Pure Price of Anarchy (for deterministic equilibria), Mixed Price of Anarchy (for randomized equilibria), and Bayes–Nash Price of Anarchy (for games with incomplete information). Solution concepts other than Nash equilibrium lead to variations such as the Price of Sinking.

The term Price of Anarchy was first used by Elias Koutsoupias and Christos Papadimitriou, but the idea of measuring inefficiency of equilibrium is older. The concept in its current form was designed to be the analogue of the 'approximation ratio' in an approximation algorithm or the 'competitive ratio' in an online algorithm. This is in the context of the current trend of analyzing games using algorithmic lenses (algorithmic game theory).

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πŸ”— Berlin Gold Hat

πŸ”— Germany πŸ”— Archaeology πŸ”— Visual arts πŸ”— Fashion

The Berlin Gold Hat or Berlin Golden Hat (German: Berliner Goldhut) is a Late Bronze Age artefact made of thin gold leaf. It served as the external covering on a long conical brimmed headdress, probably of an organic material. It is now in the Neues Museum on Museum Island in Berlin, in a room by itself with an elaborate explanatory display.

The Berlin Gold Hat is the best preserved specimen among the four known conical golden hats known from Bronze Age Europe so far. Of the three others, two were found in southern Germany, and one in the west of France. All were found in the 19th and 20th centuries. It is generally assumed that the hats served as the insignia of deities or priests in the context of a sun cult that appears to have been widespread in Central Europe at the time. The hats are also suggested to have served astronomical/calendrical functions.

The Berlin Gold Hat was acquired in 1996 by the Berlin Museum fΓΌr Vor- und FrΓΌhgeschichte as a single find without provenance. A comparative study of the ornaments and techniques in conjunction with dateable finds suggests that it was made in the Late Bronze Age, circa 1,000 to 800 BC.

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