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🔗 Mathematics

The Berry paradox is a self-referential paradox arising from an expression like "The smallest positive integer not definable in under sixty letters" (a phrase with fifty-seven letters).

Bertrand Russell, the first to discuss the paradox in print, attributed it to G. G. Berry (1867–1928), a junior librarian at Oxford's Bodleian Library. Russell called Berry "the only person in Oxford who understood mathematical logic". The paradox was called "Richard's paradox" by Jean-Yves Gerard".

🔗 Crime 🔗 Africa 🔗 Squatting 🔗 Africa/Ghana

Agbogbloshie is a nickname of a commercial district on the Korle Lagoon of the Odaw River, near the center of Accra, Ghana's capital city. Near the slum called "Old Fadama", the Agbogbloshie site became known as a destination for externally generated automobile and electronic scrap collected from mostly the western world. It was alleged to be at the center of a legal and illegal exportation network for the environmental dumping of electronic waste (e-waste) from industrialized nations. The Basel Action Network, a small NGO based in Seattle, has referred to Agbogbloshie as a "digital dumping ground", where they allege millions of tons of e-waste are processed each year.

However, repeated international studies have failed to confirm the allegations, which have been labelled an "e-waste hoax" by international reuse advocate WR3A. The most exhaustive study of the trade in used electronics in Nigeria, funded by UNEP and Basel Convention, revealed that from 540 000 tonnes of informally processed waste electronics, 52% of the material was recovered.

According to statistics from the World Bank, in large cities like Accra and Lagos the majority of households have owned televisions and computers for decades. The UN Report "Where are WEEE in Africa" (2012) disclosed that the majority of used electronics found in African dumps had not in fact been recently imported as scrap, but originated from these African cities. Agbogbloshie is situated on the banks of the Korle Lagoon, northwest of Accra's Central Business District. Roughly 40,000 Ghanaians inhabit the area, most of whom are migrants from rural areas. Due to its harsh living conditions and rampant crime, the area is nicknamed "Sodom and Gomorrah".

The Basel Convention prevents the transfrontier shipment of hazardous waste from developed to less developed countries. However, the Convention specifically allows export for reuse and repair under Annex Ix, B1110. While numerous international press reports have made reference to allegations that the majority of exports to Ghana are dumped, research by the US International Trade Commission found little evidence of unprocessed e-waste being shipped to Africa from the United States, a finding corroborated by the United Nations Environment Programme, MIT, Memorial University, Arizona State University, and other research. In 2013, the original source of the allegation blaming foreign dumping for the material found in Agbogbloshie recanted, or rather stated it had never made the claim that 80% of US e-waste is exported.

Whether domestically generated by residents of Ghana or imported, concern remains over methods of waste processing - especially burning - which emit toxic chemicals into the air, land and water. Exposure is especially hazardous to children, as these toxins are known to inhibit the development of the reproductive system, the nervous system, and especially the brain. Concerns about human health and the environment of Agbogbloshie continue to be raised as the area remains heavily polluted. In the 2000s, the Ghanaian government, with new funding and loans, implemented the Korle Lagoon Ecological Restoration Project (KLERP), an environmental remediation and restoration project that will address the pollution problem by dredging the lagoon and Odaw canal to improve drainage and flooding into the ocean.

🔗 Germany 🔗 Archaeology 🔗 Visual arts 🔗 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 für Vor- und Frühgeschichte 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.

🔗 Women's History 🔗 Iceland

On 24 October 1975, Icelandic women went on strike for the day to "demonstrate the indispensable work of women for Iceland’s economy and society" and to "protest wage discrepancy and unfair employment practices". It was then publicized domestically as Women's Day Off (Kvennafrídagurinn). Participants, led by women's organizations, did not go to their paid jobs and did not do any housework or child-rearing for the whole day. Ninety percent of Iceland's female population participated in the strike. Iceland's parliament passed a law guaranteeing equal pay the following year.

🔗 Mexico 🔗 Food and drink

Al pastor (from Spanish, "shepherd style"), tacos al pastor, or tacos de trompo is a preparation of spit-grilled slices of pork originating in the Central Mexican region of Puebla and Mexico City, although today it is a common menu item found in taquerías throughout Mexico. The method of preparing and cooking al pastor is based on the lamb shawarma brought by Lebanese immigrants to the region. Al pastor features a flavor palate that uses traditional Mexican adobada (marinade). It is a popular street food that has spread to the United States. In some places of northern Mexico and coastal Mexico, such as in Baja California, taco al pastor is known as taco de trompo or taco de adobada. A similar dish also from Puebla that uses a combination of middle eastern spices and indigenous central Mexican ingredients is called tacos árabes.

🔗 Aviation 🔗 Military history 🔗 Military history/Military aviation 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Aviation/aircraft

The North American F-82 Twin Mustang is the last American piston-engine fighter ordered into production by the United States Air Force. Based on the P-51 Mustang, the F-82 was originally designed as a long-range escort fighter in World War II. The war ended well before the first production units were operational.

In the postwar era, Strategic Air Command used the planes as a long-range escort fighter. Radar-equipped F-82s were used extensively by the Air Defense Command as replacements for the Northrop P-61 Black Widow as all-weather day/night interceptors. During the Korean War, Japan-based F-82s were among the first USAF aircraft to operate over Korea. The first three North Korean aircraft destroyed by U.S. forces were shot down by F-82s, the first being a North-Korean Yak-11 downed over Gimpo Airfield by the USAF 68th Fighter Squadron.

🔗 Physics 🔗 Astronomy 🔗 Physics/relativity 🔗 Astronomy/Astronomical objects

In general relativity, a white hole is a hypothetical region of spacetime and singularity that cannot be entered from the outside, although energy-matter, light and information can escape from it. In this sense, it is the reverse of a black hole, which can be entered only from the outside and from which energy-matter, light and information cannot escape. White holes appear in the theory of eternal black holes. In addition to a black hole region in the future, such a solution of the Einstein field equations has a white hole region in its past. This region does not exist for black holes that have formed through gravitational collapse, however, nor are there any observed physical processes through which a white hole could be formed.

Supermassive black holes (SBHs) are theoretically predicted to be at the center of every galaxy and that possibly, a galaxy cannot form without one. Stephen Hawking and others have proposed that these SBHs spawn a supermassive white hole/Big Bang.

🔗 Computer science

The Q notation is a succinct way to specify the parameters of a binary fixed point number format. A number of other notations have been used for the same purpose.

🔗 Military history

🔗 Psychology 🔗 Sociology 🔗 Media

The spiral of silence theory is a political science and mass communication theory proposed by the German political scientist Elisabeth Noelle-Neumann. It states that an individual's perception of the distribution of public opinion influences that individual's willingness to express their own opinions, which in turn affects the perceptions and, ultimately, willingness of others to express their opinions. The main idea is that people influence each other's willingness to express opinions through social interaction. According to the spiral of silence theory, individuals will be more confident and outward with their opinion when they notice that their personal opinion is shared throughout a group. But if the individual notices that their opinion is unpopular with the group they will be more inclined to be reserved and remain silent. In other words, from the individual's perspective, "not isolating himself is more important than his own judgement", meaning his perception of how others in the group perceive him is more important to himself than the need for his opinion to be heard.

According to Glynn (1995), "the major components of the spiral of silence include (1) an issue of public interest; (2) divisiveness on the issue; (3) a quasi-statistical sense that helps an individual perceive the climate of opinion as well as estimate the majority and minority opinion; (4) 'fear of isolation' from social interaction "(though, whether this is a causal factor in the willingness to speak out is contested)"; (5) an individual's belief that a minority (or 'different') opinion isolates oneself from others; and (6) a 'hardcore' group of people whose opinions are unaffected by others' opinions."