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🔗 1984 Rajneeshee bioterror attack

🔗 United States 🔗 Medicine 🔗 Oregon 🔗 Crime 🔗 Religion 🔗 Biology 🔗 Terrorism

The 1984 Rajneeshee bioterror attack was the food poisoning of 751 individuals in The Dalles, Oregon, through the deliberate contamination of salad bars at ten local restaurants with Salmonella. A group of prominent followers of Bhagwan Shree Rajneesh (later known as Osho) led by Ma Anand Sheela had hoped to incapacitate the voting population of the city so that their own candidates would win the 1984 Wasco County elections. The incident was the first and is the single largest bioterrorist attack in United States history.

Having previously gained political control of Antelope, Oregon, Rajneesh's followers, who were based in nearby Rajneeshpuram, sought election to two of the three seats on the Wasco County Circuit Court that were up for election in November 1984. Fearing they would not gain enough votes, some Rajneeshpuram officials decided to incapacitate voters in The Dalles, the largest population center in Wasco County. The chosen biological agent was Salmonella enterica Typhimurium, which was first delivered through glasses of water to two County Commissioners and then, on a larger scale, at salad bars and in salad dressing.

As a result of the attack, 751 people contracted salmonellosis, 45 of whom were hospitalized, but none died. Although an initial investigation by the Oregon Public Health Division and the Centers for Disease Control did not rule out deliberate contamination, the agents and contamination were only confirmed a year later. On February 28, 1985, Congressman James H. Weaver gave a speech in the United States House of Representatives in which he "accused the Rajneeshees of sprinkling Salmonella culture on salad bar ingredients in eight restaurants".

At a press conference in September 1985, Rajneesh accused several of his followers of participation in this and other crimes, including an aborted plan in 1985 to assassinate a United States Attorney, and he asked state and federal authorities to investigate. Oregon Attorney General David B. Frohnmayer set up an interagency task force, composed of Oregon State Police and the Federal Bureau of Investigation, and executed search warrants in Rajneeshpuram. A sample of bacteria matching the contaminant that had sickened the town residents was found in a Rajneeshpuram medical laboratory. Two leading Rajneeshpuram officials were convicted on charges of attempted murder and served 29 months of 20-year sentences in a minimum-security federal prison.

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🔗 The SOLID principles of object-oriented design

🔗 Computing 🔗 Computing/Software 🔗 Computing/Computer science

In object-oriented computer programming, SOLID is a mnemonic acronym for five design principles intended to make software designs more understandable, flexible and maintainable. It is not related to the GRASP software design principles. The principles are a subset of many principles promoted by American software engineer and instructor Robert C. Martin. Though they apply to any object-oriented design, the SOLID principles can also form a core philosophy for methodologies such as agile development or adaptive software development. The theory of SOLID principles was introduced by Martin in his 2000 paper Design Principles and Design Patterns, although the SOLID acronym was introduced later by Michael Feathers.

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🔗 Gastronorm

🔗 Food and drink

Gastronorm (GN), sometimes spelled Gastro-Norm, is a European standard for kitchenware tray and container sizes that is commonly seen worldwide in the catering and professional food industry, as well as in certain parts of the high-end consumer market. Gastronorm is generally used worldwide except in most of the United States and Canada, which have their own domestic systems. The Gastronorm standard was first introduced in Switzerland in 1964 and became an official European standard in 1993 with the EN 631 standard.

The basic format is called "GN 1/1" and measures 530×325 mm, with other Gastronorm sizes being multiples and fractions of this basic module size. Gastronorm containers allow for flexible, place efficient, and compatible storage, transport, processing, and serving and can be adapted for shelving, transport on trolleys and conveyor belts, secure temporary placement in compatible sinks, working tables, refrigerators, freezers, ovens, hot water baths, and compatible dishwashers, or display. Other products that have adopted the Gastronorm format include cutting boards and non-stick mats. Many professional food products are even packaged for optimal compatibility with Gastronorm containers, such as pizza base sizes, pre-baked breads, or frozen vegetables.

The most commonly used materials for the containers are stainless steel and (transparent or non-transparent) plastic. Stackable baking trays and stainless steel containers are commonly used for cooking in an oven, while polycarbonate and polypropylene variants are suited for storage of cold foods. Porcelain or melamine containers are used for display.

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🔗 Ettore Majorana

🔗 Biography 🔗 Physics 🔗 Biography/science and academia 🔗 Physics/Biographies 🔗 Sicily

Ettore Majorana (, Italian: [ˈɛttore majoˈraːna]; born on 5 August 1906 – likely dying in or after 1959) was an Italian theoretical physicist who worked on neutrino masses. On 25 March 1938, he disappeared under mysterious circumstances after purchasing a ticket to travel by ship from Naples to Palermo.

The Majorana equation and Majorana fermions are named after him. In 2006, the Majorana Prize was established in his memory.

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🔗 The Market for Lemons

🔗 Economics

"The Market for Lemons: Quality Uncertainty and the Market Mechanism" is a well-known 1970 paper by economist George Akerlof which examines how the quality of goods traded in a market can degrade in the presence of information asymmetry between buyers and sellers, leaving only "lemons" behind. In American slang, a lemon is a car that is found to be defective after it has been bought.

Suppose buyers cannot distinguish between a high-quality car (a "peach") and a "lemon". Then they are only willing to pay a fixed price for a car that averages the value of a "peach" and "lemon" together (pavg). But sellers know whether they hold a peach or a lemon. Given the fixed price at which buyers will buy, sellers will sell only when they hold "lemons" (since plemon < pavg) and they will leave the market when they hold "peaches" (since ppeach > pavg). Eventually, as enough sellers of "peaches" leave the market, the average willingness-to-pay of buyers will decrease (since the average quality of cars on the market decreased), leading to even more sellers of high-quality cars to leave the market through a positive feedback loop.

Thus the uninformed buyer's price creates an adverse selection problem that drives the high-quality cars from the market. Adverse selection is a market mechanism that can lead to a market collapse.

Akerlof's paper shows how prices can determine the quality of goods traded on the market. Low prices drive away sellers of high-quality goods, leaving only lemons behind. In 2001, Akerlof, along with Michael Spence, and Joseph Stiglitz, jointly received the Nobel Memorial Prize in Economic Sciences, for their research on issues related to asymmetric information.

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🔗 A hypercane is a hypothetical class of extreme tropical cyclone

🔗 Meteorology 🔗 Tropical cyclones

A hypercane is a hypothetical class of extreme tropical cyclone that could form if ocean temperatures reached approximately 50 °C (122 °F), which is 15 °C (27 °F) warmer than the warmest ocean temperature ever recorded. Such an increase could be caused by a large asteroid or comet impact, a large supervolcanic eruption, a large submarine flood basalt, or extensive global warming. There is some speculation that a series of hypercanes resulting from an impact by a large asteroid or comet contributed to the demise of the non-avian dinosaurs. The hypothesis was created by Kerry Emanuel of MIT, who also coined the term.

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🔗 Dagen H – the day Sweden switched to driving on the right

🔗 Transport 🔗 Sweden

Dagen H (H day), today usually called "Högertrafikomläggningen" ("The right-hand traffic diversion"), was the day on 3 September 1967, in which the traffic in Sweden switched from driving on the left-hand side of the road to the right. The "H" stands for "Högertrafik", the Swedish word for "right traffic". It was by far the largest logistical event in Sweden's history.

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🔗 Atanasoff–Berry Computer

🔗 United States 🔗 Computing 🔗 Computing/Computer hardware 🔗 Computing/Early computers 🔗 United States/Iowa

The Atanasoff–Berry computer (ABC) was the first automatic electronic digital computer. Limited by the technology of the day, and execution, the device has remained somewhat obscure. The ABC's priority is debated among historians of computer technology, because it was neither programmable, nor Turing-complete. Conventionally, the ABC would be considered the first electronic ALU (arithmetic logic unit) – which is integrated into every modern processor's design.

Its unique contribution was to make computing faster by being the first to use vacuum tubes to do the arithmetic calculations. Prior to this, slower electro-mechanical methods were used by Konrad Zuse's Z1, and the simultaneously developed Harvard Mark I. The first electronic, programmable, digital machine, the Colossus computer from 1943 to 1945, used similar tube-based technology as ABC.

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🔗 Bremermann's limit

🔗 Computing 🔗 Physics 🔗 Systems 🔗 Systems/Cybernetics

Bremermann's limit, named after Hans-Joachim Bremermann, is a limit on the maximum rate of computation that can be achieved in a self-contained system in the material universe. It is derived from Einstein's mass-energy equivalency and the Heisenberg uncertainty principle, and is c2/h ≈ 1.36 × 1050 bits per second per kilogram. This value is important when designing cryptographic algorithms, as it can be used to determine the minimum size of encryption keys or hash values required to create an algorithm that could never be cracked by a brute-force search.

For example, a computer with the mass of the entire Earth operating at the Bremermann's limit could perform approximately 1075 mathematical computations per second. If one assumes that a cryptographic key can be tested with only one operation, then a typical 128-bit key could be cracked in under 10−36 seconds. However, a 256-bit key (which is already in use in some systems) would take about two minutes to crack. Using a 512-bit key would increase the cracking time to approaching 1072 years, without increasing the time for encryption by more than a constant factor (depending on the encryption algorithms used).

The limit has been further analysed in later literature as the maximum rate at which a system with energy spread Δ E {\displaystyle \Delta E} can evolve into an orthogonal and hence distinguishable state to another, Δ t = π 2 Δ E . {\displaystyle \Delta t={\frac {\pi \hbar }{2\Delta E}}.} In particular, Margolus and Levitin have shown that a quantum system with average energy E takes at least time Δ t = π 2 E {\displaystyle \Delta t={\frac {\pi \hbar }{2E}}} to evolve into an orthogonal state. However, it has been shown that access to quantum memory in principle allows computational algorithms that require arbitrarily small amount of energy/time per one elementary computation step.

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🔗 Snobol (“StriNg Oriented and SymBOlic Language”)

🔗 Computing 🔗 Computer science 🔗 Software 🔗 Software/Computing

SNOBOL ("StriNg Oriented and symBOlic Language") is a series of programming languages developed between 1962 and 1967 at AT&T Bell Laboratories by David J. Farber, Ralph E. Griswold and Ivan P. Polonsky, culminating in SNOBOL4. It was one of a number of text-string-oriented languages developed during the 1950s and 1960s; others included COMIT and TRAC.

SNOBOL4 stands apart from most programming languages of its era by having patterns as a first-class data type (i.e. a data type whose values can be manipulated in all ways permitted to any other data type in the programming language) and by providing operators for pattern concatenation and alternation. SNOBOL4 patterns are a type of object and admit various manipulations, much like later object-oriented languages such as JavaScript whose patterns are known as regular expressions. In addition SNOBOL4 strings generated during execution can be treated as programs and either interpreted or compiled and executed (as in the eval function of other languages).

SNOBOL4 was quite widely taught in larger U.S. universities in the late 1960s and early 1970s and was widely used in the 1970s and 1980s as a text manipulation language in the humanities.

In the 1980s and 1990s, its use faded as newer languages such as AWK and Perl made string manipulation by means of regular expressions fashionable. SNOBOL4 patterns subsume BNF grammars, which are equivalent to context-free grammars and more powerful than regular expressions. The "regular expressions" in current versions of AWK and Perl are in fact extensions of regular expressions in the traditional sense, but regular expressions, unlike SNOBOL4 patterns, are not recursive, which gives a distinct computational advantage to SNOBOL4 patterns. (Recursive expressions did appear in Perl 5.10, though, released in December 2007.)

The later SL5 (1977) and Icon (1978) languages were designed by Griswold to combine the backtracking of SNOBOL4 pattern matching with more standard ALGOL-like structuring.

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