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🔗 Davy Crockett (nuclear device)

🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/Weaponry 🔗 Military history/Cold War 🔗 Pritzker Military Library 🔗 Firearms

The M-28 or M-29 Davy Crockett Weapon System was the tactical nuclear recoilless gun (smoothbore) for firing the M-388 nuclear projectile that was deployed by the United States during the Cold War. It was one of the smallest nuclear weapon systems ever built, with a yield between 10 and 20 tons TNT equivalent (40–80 gigajoules). It is named after American folk hero, soldier, and congressman Davy Crockett.

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🔗 Pizza Effect

🔗 Religion 🔗 Sociology

In religious studies and sociology, the pizza effect is the phenomenon of elements of a nation or people's culture being transformed or at least more fully embraced elsewhere, then re-imported back to their culture of origin, or the way in which a community's self-understanding is influenced by (or imposed by, or imported from) foreign sources. It is named after the idea that modern pizza toppings were developed among Italian immigrants in the United States (rather than in native Italy, where in its simpler form it was originally looked down upon), and was later exported back to Italy to be interpreted as a delicacy in Italian cuisine.

Related phrases include "hermeneutical feedback loop", "re-enculturation", and "self-orientalization". The term "pizza effect" was coined by the Austrian-born Hindu monk and professor of Anthropology at Syracuse University, Agehananda Bharati in 1970.

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🔗 Tuskegee Syphilis Study

🔗 Human rights 🔗 Medicine 🔗 History of Science 🔗 Alabama 🔗 Science Policy 🔗 Nursing

The Tuskegee Study of Untreated Syphilis in the Negro Male (informally referred to as the Tuskegee Experiment or Tuskegee Syphilis Study) was a study conducted between 1932 and 1972 by the United States Public Health Service (PHS) and the Centers for Disease Control and Prevention (CDC) on a group of nearly 400 African American men with syphilis. The purpose of the study was to observe the effects of the disease when untreated, though by the end of the study medical advancements meant it was entirely treatable. The men were not informed of the nature of the experiment, and more than 100 died as a result.

The Public Health Service started the study in 1932 in collaboration with Tuskegee University (then the Tuskegee Institute), a historically Black college in Alabama. In the study, investigators enrolled a total of 600 impoverished African-American sharecroppers from Macon County, Alabama. Of these men, 399 had latent syphilis, with a control group of 201 men who were not infected. As an incentive for participation in the study, the men were promised free medical care. While the men were provided with both medical and mental care that they otherwise would not have received, they were deceived by the PHS, who never informed them of their syphilis diagnosis and provided disguised placebos, ineffective methods, and diagnostic procedures as treatment for "bad blood".

The men were initially told that the experiment was only going to last six months, but it was extended to 40 years. After funding for treatment was lost, the study was continued without informing the men that they would never be treated. None of the infected men were treated with penicillin despite the fact that, by 1947, the antibiotic was widely available and had become the standard treatment for syphilis.

The study continued, under numerous Public Health Service supervisors, until 1972, when a leak to the press resulted in its termination on November 16 of that year. By then, 28 patients had died directly from syphilis, 100 died from complications related to syphilis, 40 of the patients' wives were infected with syphilis, and 19 children were born with congenital syphilis.

The 40-year Tuskegee Study was a major violation of ethical standards and has been cited as "arguably the most infamous biomedical research study in U.S. history." Its revelation led to the 1979 Belmont Report and to the establishment of the Office for Human Research Protections (OHRP) and federal laws and regulations requiring institutional review boards for the protection of human subjects in studies. The OHRP manages this responsibility within the United States Department of Health and Human Services (HHS). Its revelation has also been an important cause of distrust in medical science and the US government amongst African Americans.

On May 16, 1997, President Bill Clinton formally apologized on behalf of the United States to victims of the study, calling it shameful and racist. "What was done cannot be undone, but we can end the silence," he said. "We can stop turning our heads away. We can look at you in the eye, and finally say, on behalf of the American people, what the United States government did was shameful and I am sorry."

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🔗 Traitorous Eight

🔗 California 🔗 California/San Francisco Bay Area 🔗 Computing 🔗 Computing/Computer hardware

The traitorous eight was a group of eight employees who left Shockley Semiconductor Laboratory in 1957 to found Fairchild Semiconductor. William Shockley had in 1956 recruited a group of young PhD graduates with the goal to develop and produce new semiconductor devices. While Shockley had received a Nobel Prize in Physics and was an experienced researcher and teacher, his management of the group was authoritarian and unpopular. This was accentuated by Shockley's research focus not proving fruitful. After the demand for Shockley to be replaced was rebuffed, the eight left to form their own company.

Shockley described their leaving as a "betrayal". The eight who left Shockley Semiconductor were Julius Blank, Victor Grinich, Jean Hoerni, Eugene Kleiner, Jay Last, Gordon Moore, Robert Noyce, and Sheldon Roberts. In August 1957, they reached an agreement with Sherman Fairchild, and on September 18, 1957, they formed Fairchild Semiconductor. The newly founded Fairchild Semiconductor soon grew into a leader of the semiconductor industry. In 1960, it became an incubator of Silicon Valley and was directly or indirectly involved in the creation of dozens of corporations, including Intel and AMD. These many spin-off companies came to be known as "Fairchildren".

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🔗 Kramatorsk Radiological Accident

🔗 Disaster management 🔗 Ukraine

The Kramatorsk radiological accident was a radiation accident that happened in Kramatorsk, in the Ukrainian SSR from 1980 to 1989. A small capsule containing highly radioactive caesium-137 was found inside the concrete wall of an apartment building, with a surface gamma radiation exposure dose rate of 1800 R/year. The capsule was detected only after residents requested that the level of radiation in the apartment be measured by a health physicist.

The capsule was originally part of a radiation level gauge and was lost in the Karansky quarry in the late 1970s. The search for the capsule was unsuccessful and ended after a week. The gravel from the quarry was used in construction. The caesium capsule ended up in the concrete panel of apartment 85 of building 7 on Mariyi Pryimachenko Street (at the time under the Soviet name Gvardeytsiv Kantemirovtsiv), between apartments 85 and 52.

Over nine years, two families lived in apartment 85. A child's bed was located directly next to the wall containing the capsule. The apartment was fully settled in 1980. A year later, an 18-year-old woman who lived there suddenly died. In 1982, her 16-year-old brother followed, and then their mother. Even after that the flat did not attract much public attention, despite the fact that the residents all died from leukemia. Doctors were unable to determine root-cause of illness and explained the diagnosis by poor heredity. A new family moved into the apartment, and their son died from leukemia as well. His father managed to start a detailed investigation, during which the vial was found in the wall in 1989.

By the time the capsule was discovered, four residents of the building had died from it and 17 more had received varying doses of radiation. Part of the wall was removed and sent to the Institute for Nuclear Research, where the caesium capsule was removed, identified by serial number and disposed of.

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🔗 Akaike information criterion

🔗 Mathematics 🔗 Statistics

The Akaike information criterion (AIC) is an estimator of out-of-sample prediction error and thereby relative quality of statistical models for a given set of data. Given a collection of models for the data, AIC estimates the quality of each model, relative to each of the other models. Thus, AIC provides a means for model selection.

AIC is founded on information theory. When a statistical model is used to represent the process that generated the data, the representation will almost never be exact; so some information will be lost by using the model to represent the process. AIC estimates the relative amount of information lost by a given model: the less information a model loses, the higher the quality of that model.

In estimating the amount of information lost by a model, AIC deals with the trade-off between the goodness of fit of the model and the simplicity of the model. In other words, AIC deals with both the risk of overfitting and the risk of underfitting.

The Akaike information criterion is named after the Japanese statistician Hirotugu Akaike, who formulated it. It now forms the basis of a paradigm for the foundations of statistics; as well, it is widely used for statistical inference.

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🔗 Ur

🔗 Ancient Near East 🔗 Bible 🔗 Iraq 🔗 Archaeology 🔗 Cities

Ur was an important Sumerian city-state in ancient Mesopotamia, located at the site of modern Tell el-Muqayyar (Arabic: تل ٱلْمُقَيَّر) in south Iraq's Dhi Qar Governorate. Although Ur was once a coastal city near the mouth of the Euphrates on the Persian Gulf, the coastline has shifted and the city is now well inland, on the south bank of the Euphrates, 16 kilometres (9.9 miles) from Nasiriyah in modern-day Iraq. The city dates from the Ubaid period circa 3800 BC, and is recorded in written history as a city-state from the 26th century BC, its first recorded king being Mesannepada.

The city's patron deity was Nanna (in Akkadian, Sin), the Sumerian and Akkadian moon god, and the name of the city is in origin derived from the god's name, UNUGKI, literally "the abode (UNUG) of Nanna". The site is marked by the partially restored ruins of the Ziggurat of Ur, which contained the shrine of Nanna, excavated in the 1930s. The temple was built in the 21st century BC (short chronology), during the reign of Ur-Nammu and was reconstructed in the 6th century BC by Nabonidus, the last king of Babylon. The ruins cover an area of 1,200 metres (3,900 ft) northwest to southeast by 800 metres (2,600 ft) northeast to southwest and rise up to about 20 metres (66 ft) above the present plain level.

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  • "Ur" | 2022-11-12 | 509 Upvotes 103 Comments

🔗 Homoiconicity

🔗 Computing

In computer programming, homoiconicity (from the Greek words homo- meaning "the same" and icon meaning "representation") is a property of some programming languages. A language is homoiconic if a program written in it can be manipulated as data using the language, and thus the program's internal representation can be inferred just by reading the program itself. For example, a Lisp program is written as a regular Lisp list, and can be manipulated by other Lisp code. In homoiconic languages, all code can be accessed and transformed as data, using the same representation. This property is often summarized by saying that the language treats "code as data".

In a homoiconic language, the primary representation of programs is also a data structure in a primitive type of the language itself. This makes metaprogramming easier than in a language without this property: reflection in the language (examining the program's entities at runtime) depends on a single, homogeneous structure, and it does not have to handle several different structures that would appear in a complex syntax.

As noted above, a commonly cited example is Lisp, which was created to allow for easy list manipulations and where the structure is given by S-expressions that take the form of nested lists. Lisp programs are written in the form of lists; the result is that the program can access its own functions and procedures while running, and programmatically alter itself on the fly. Homoiconic languages typically include full support of syntactic macros, allowing the programmer to express transformations of programs in a concise way. Examples are the programming languages Clojure (a contemporary dialect of Lisp), Rebol (also its successor Red), Refal, Prolog, and more recently Julia.

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🔗 Great Britain road numbering scheme

🔗 Highways 🔗 Road transport 🔗 Transport in Scotland 🔗 Highways/United Kingdom Roads 🔗 UK geography

The Great Britain road numbering scheme is a numbering scheme used to classify and identify all roads in Great Britain. Each road is given a single letter, which represents the road's category, and a subsequent number, of 1 to 4 digits. Introduced to arrange funding allocations, the numbers soon became used on maps and as a method of navigation. Two sub-schemes exist: one for motorways, and another for non-motorway roads. While some major roads form part of the International E-road network, no E-routes are signposted in Great Britain, or the rest of the UK.

The scheme applies only to Great Britain (England, Scotland and Wales); a similar system is used in Northern Ireland, as well as outside the UK in the Isle of Man, Jersey and British overseas territories. These other numbering schemes use similar conventions.

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🔗 Wikipedia entry for Aaron Swartz-founded PAC was deleted the day he died

🔗 Internet

Demand Progress is an internet activist-related entity encompassing a 501(c)4 arm sponsored by the 1630 Fund and a 501(c)3 arm sponsored by the New Venture Fund. It specializes in online-intensive and other grassroots activism to support Internet freedom, civil liberties, transparency, and human rights, and in opposition to censorship and corporate control of government. The organization was founded through a petition in opposition to the Combating Online Infringement and Counterfeits Act, sparking the movement that eventually defeated COICA's successor bills, the Stop Online Piracy Act and the PROTECT IP Act, two highly controversial pieces of United States legislation.

The organization has continued to fight for such causes in the wake of the successful shelving of these two acts. Demand Progress has also played key roles in forwarding the passage of net neutrality rules, blocking expansion of the Computer Fraud and Abuse Act, under which co-founder Aaron Swartz was indicted, and other key legislative efforts. Estimated membership numbers in early 2015 weigh in at over two million. As of late 2013, the organization encompasses the Demand Progress, Rootstrikers and Watchdog.net wings/brands.