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🔗 Soviet Union 🔗 Russia 🔗 Law 🔗 Politics 🔗 Cities 🔗 Russia/Russian, Soviet, and CIS military history 🔗 Russia/politics and law of Russia 🔗 Russia/human geography of Russia

A closed city or closed town is a settlement where travel or residency restrictions are applied so that specific authorization is required to visit or remain overnight. They may be sensitive military establishments or secret research installations that require much more space or freedom than is available in a conventional military base. There may also be a wider variety of permanent residents including close family members of workers or trusted traders who are not directly connected with its clandestine purposes.

Many closed cities existed in the Soviet Union until its collapse in 1991. After 1991, a number of them still existed in the CIS countries, especially Russia. In modern Russia, such places are officially known as "closed administrative-territorial formations" (закрытые административно-территориальные образования, zakrytye administrativno-territorial'nye obrazovaniya, or ЗАТО ZATO for short).

🔗 Palaeontology 🔗 Amphibians and Reptiles 🔗 Mammals

Dimetrodon ( (listen) or , meaning "two measures of teeth") is an extinct genus of non-mammalian synapsids that lived during the Cisuralian (Early Permian), around 295–272 million years ago (Ma). It is a member of the family Sphenacodontidae. The most prominent feature of Dimetrodon is the large neural spine sail on its back formed by elongated spines extending from the vertebrae. It walked on four legs and had a tall, curved skull with large teeth of different sizes set along the jaws. Most fossils have been found in the southwestern United States, the majority coming from a geological deposit called the Red Beds of Texas and Oklahoma. More recently, fossils have been found in Germany. Over a dozen species have been named since the genus was first described in 1878.

Dimetrodon is often mistaken for a dinosaur or as a contemporary of dinosaurs in popular culture, but it became extinct some 40 million years before the first appearance of dinosaurs. Reptile-like in appearance and physiology, Dimetrodon is nevertheless more closely related to mammals than to modern reptiles, though it is not a direct ancestor of mammals. Dimetrodon is assigned to the "non-mammalian synapsids", a group traditionally called "mammal-like reptiles". This groups Dimetrodon together with mammals in a clade (evolutionary group) called Synapsida, while placing dinosaurs, reptiles and birds in a separate clade, Sauropsida. Single openings in the skull behind each eye, known as temporal fenestrae, and other skull features distinguish Dimetrodon and mammals from most of the earliest sauropsids.

Dimetrodon was probably one of the apex predators of the Cisuralian ecosystems, feeding on fish and tetrapods, including reptiles and amphibians. Smaller Dimetrodon species may have had different ecological roles. The sail of Dimetrodon may have been used to stabilize its spine or to heat and cool its body as a form of thermoregulation. Some recent studies argue that the sail would have been ineffective at removing heat from the body due to large species being discovered with small sails and small species being discovered with large sails, essentially ruling out heat regulation as its main purpose. The sail was most likely used in courtship display with methods such as threatening rivals or showing off to potential mates.

🔗 Computing 🔗 Computing/Computer hardware

Viewtron was an online service offered by Knight-Ridder and AT&T from 1983 to 1986. Patterned after the British Post Office's Prestel system, it started as a videotex service requiring users to have a special terminal, the AT&T Sceptre. As home computers became important in the marketplace, the development focus shifted to IBM, Apple, Commodore and other personal computers.

Viewtron differed from contemporary services like CompuServe and The Source by emphasizing news from The Miami Herald and Associated Press and e-commerce services from JCPenney and other merchants over computer-oriented services such as file downloads or online chat. Intended to be "the McDonald's of videotex," Viewtron was specifically targeted toward users who would be apprehensive about using a computer.

Viewtron also offered airline schedules from the Official Airline Guide (OAG), real estate research from Century 21, e-cards from Hallmark, product information from Consumer Reports, educational software from Scott Foresman, online auctions, financial services from American Express and EF Hutton, as well as limited online banking services as part of a research program into the uses and costs of banking online that included 20 US and Canadian banks.

At its height, Viewtron was operated in at least 15 cities by various newspaper companies. After six years of research and an investment reportedly in excess of $50 million, Viewtron never turned a profit, and, despite its developer's forecasts of breaking even in two years, Knight Ridder did not expect it ever would be profitable. AT&T had invested over $100 million in the project, but was forced to write off that investment as part of its court-ordered breakup. Viewtron closed on March 31, 1986, after an attempt by the Independent Commodore Users Group to buy the service failed.

A feature tying Viewtron to local newspapers was envisioned, with printed text instructing users how to access further information online, but it was never implemented.

In 2008, PCWorld magazine named Viewtron to a list of the biggest project failures in information technology (IT) history.

🔗 Medicine 🔗 Conservatism

Ronald Reagan Speaks Out Against Socialized Medicine is a 1961 LP featuring the actor Ronald Reagan. In this more than ten-minute recording, Reagan "criticized Social Security for supplanting private savings and warned that subsidized medicine would curtail Americans' freedom" and that "pretty soon your son won't decide when he's in school, where he will go or what he will do for a living. He will wait for the government to tell him." Roger Lowenstein called the LP part of a "stealth program" conducted by the American Medical Association (see Operation Coffee Cup).

🔗 Apple Inc./Macintosh 🔗 Apple Inc. 🔗 Computing 🔗 Apple Inc./iOS

Mach () is a kernel developed at Carnegie Mellon University to support operating system research, primarily distributed and parallel computing. Mach is often mentioned as one of the earliest examples of a microkernel. However, not all versions of Mach are microkernels. Mach's derivatives are the basis of the operating system kernel in GNU Hurd and of Apple's XNU kernel used in macOS, iOS, iPadOS, tvOS, and watchOS.

The project at Carnegie Mellon ran from 1985 to 1994, ending with Mach 3.0, which is a true microkernel. Mach was developed as a replacement for the kernel in the BSD version of Unix, so no new operating system would have to be designed around it. Mach and its derivatives exist within a number of commercial operating systems. These include all using the XNU operating system kernel which incorporates an earlier non-microkernel Mach as a major component. The Mach virtual memory management system was also adopted in 4.4BSD by the BSD developers at CSRG, and appears in modern BSD-derived Unix systems, such as FreeBSD.

Mach is the logical successor to Carnegie Mellon's Accent kernel. The lead developer on the Mach project, Richard Rashid, has been working at Microsoft since 1991 in various top-level positions revolving around the Microsoft Research division. Another of the original Mach developers, Avie Tevanian, was formerly head of software at NeXT, then Chief Software Technology Officer at Apple Inc. until March 2006.

🔗 Human rights 🔗 Russia 🔗 Crime 🔗 Religion 🔗 Islam 🔗 LGBT studies 🔗 Sociology 🔗 Chechnya 🔗 Discrimination 🔗 Correction and Detention Facilities 🔗 Sexology and sexuality

Anti-gay purges in the Chechen Republic, a part of the Russian Federation, have included forced disappearances — secret abductions, imprisonment, torture — and extrajudicial killing by authorities targeting persons based on their perceived sexual orientation. An unknown number of people, who authorities detained on suspicion of being gay or bisexual, have reportedly died after being held in what human rights groups and eyewitnesses have called concentration camps.

Allegations were initially reported on 1 April 2017 in Novaya Gazeta, a Russian-language opposition newspaper, which reported that since February 2017 over 100 men had allegedly been detained and tortured and at least three had died in an extrajudicial killing. The paper, citing its sources in the Chechen special services, called the wave of detentions a "prophylactic sweep". The journalist who first reported on the subject went into hiding. There have been calls for reprisals against journalists who report on the situation.

As news spread of Chechen authorities' actions, which have been described as part of a systematic anti-LGBT purge, Russian and international activists scrambled to evacuate survivors of the camps and other vulnerable Chechens but were met with difficulty obtaining visas to conduct them safely beyond Russia.

The reports of the persecution were met with a variety of reactions worldwide. The Head of the Chechen Republic Ramzan Kadyrov denied not only the occurrence of any persecution but also the existence of gay men in Chechnya, adding that such people would be killed by their own families. Officials in Moscow were skeptical, although in late May the Russian government reportedly agreed to send an investigative team to Chechnya. Numerous national leaders and other public figures in the West condemned Chechnya's actions, and protests were held in Russia and elsewhere. A report released in December 2018 by the Organization for Security and Cooperation in Europe (OSCE) confirmed claims that persecution of LGBT persons had taken place and was ignored by authorities.

On 11 January 2019, it was reported that another 'gay purge' had begun in the country in December 2018, with several gay men and women being detained. The Russian LGBT Network believes that around 40 persons were detained and two killed.

🔗 Medicine 🔗 Linguistics 🔗 Linguistics/Applied Linguistics

Semantic satiation is a psychological phenomenon in which repetition causes a word or phrase to temporarily lose meaning for the listener, who then perceives the speech as repeated meaningless sounds. Extended inspection or analysis (staring at the word or phrase for a lengthy period of time) in place of repetition also produces the same effect.

🔗 India 🔗 Numismatics 🔗 India/Indian politics workgroup

A zero-rupee note is a banknote imitation issued in India as a means of helping to fight systemic political corruption. The notes are "paid" in protest by angry citizens to government functionaries who solicit bribes in return for services which are supposed to be free. Zero rupee notes, which are made to resemble the regular 50 rupee banknote of India, are the creation of a non-governmental organization known as 5th Pillar which has, since their inception in 2007, distributed over 2.5 million notes as of August 2014. The notes remain in current use and thousands of notes are distributed every month.

🔗 Spaceflight 🔗 Physics 🔗 Science Fiction

A black hole starship is a theoretical idea for enabling interstellar travel by propelling a starship by using a black hole as the energy source. The concept was first discussed in science fiction, notably in the book Imperial Earth by Arthur C. Clarke, and in the work of Charles Sheffield, in which energy extracted from a Kerr-Newman black hole is described as powering the rocket engines in the story "Killing Vector" (1978).

In a more detailed analysis, a proposal to create an artificial black hole and using a parabolic reflector to reflect its Hawking radiation was discussed in 2009 by Louis Crane and Shawn Westmoreland. Their conclusion was that it was on the edge of possibility, but that quantum gravity effects that are presently unknown will either make it easier, or make it impossible. Similar concepts were also sketched out by Bolonkin.

🔗 United States 🔗 Numismatics 🔗 Numismatics/American currency 🔗 United States/Massachusetts

BerkShares is a local currency that circulates in The Berkshires region of Massachusetts. It was launched on September 29, 2006 by BerkShares Inc., with research and development assistance from the Schumacher Center for a New Economics. The BerkShares website lists around 400 businesses in Berkshire County that accept the currency. Since launch, over 10 million BerkShares have been issued from participating branch offices of local banks (as of February 2020, 9 branches of 3 different banks). The bills were designed by John Isaacs and were printed by Excelsior Printing on special paper with incorporated security features from Crane & Co.. BerkShares are pegged with an exchange rate to the US dollar, but the Schumacher Center has discussed the possibility of pegging its value to a basket of local goods in order to insulate the local economy against volatility in the US economy.