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🔗 Mathematics

In number theory, specifically the study of Diophantine approximation, the lonely runner conjecture is a conjecture about the long-term behavior of runners on a circular track. It states that ${\displaystyle n}$ runners on a track of unit length, with constant speeds all distinct from one another, will each be lonely at some time—at least ${\displaystyle 1/n}$ units away from all others.

The conjecture was first posed in 1967 by German mathematician Jörg M. Wills, in purely number-theoretic terms, and independently in 1974 by T. W. Cusick; its illustrative and now-popular formulation dates to 1998. The conjecture is known to be true for 7 runners or less, but the general case remains unsolved. Implications of the conjecture include solutions to view-obstruction problems and bounds on properties, related to chromatic numbers, of certain graphs.

🔗 United States 🔗 Plants

The American chestnut (Castanea dentata) is a large deciduous tree of the beech family native to eastern North America. The American chestnut was one of the most important forest trees throughout its range and was considered the finest chestnut tree in the world.

The species was devastated by chestnut blight, a fungal disease that came from Chinese chestnut trees introduced into North America from East Asia. It is estimated that between 3 and 4 billion American chestnut trees were destroyed in the first half of the 20th century by chestnut blight after the blight's initial discovery in North America in 1904. Very few mature specimens of the tree exist within its historical range, although many small shoots of the former live trees remain. There are hundreds of large (2 to 5 ft diameter) American chestnuts outside its historical range, some in areas where less virulent strains of the pathogen are more common, such as the 600 to 800 large trees in Northern Michigan. The species is listed as endangered in the United States and Canada. American chestnuts are also susceptible to ink disease, particularly in the southern part of its native range. This susceptibility to ink disease may have contributed to the devastation of the species.

Several groups are attempting to create blight-resistant American chestnuts. Scientists at the SUNY College of Environmental Science and Forestry created the Darling 58 cultivar of American chestnut by inserting the oxalate oxidase gene from wheat into the genome of an American chestnut. When expressed in the cambium of the Darling 58 cultivar, oxalate oxidase detoxifies oxalic acid, resulting in a tree that still gets infected by the blight fungus but that resists girdling of the trunk and survives such infection. As of 2021, the researchers who developed this cultivar are working towards applying for government permission to make these trees available to the public. If approved, these chestnut trees would be the first genetically modified forest trees released into the wild in the United States. Cross-breeding of chestnut species represents an alternate approach to restoring the American chestnut. One approach has been cross-breeding among different partially blight-resistant American chestnuts, with the goal of developing a cultivar with high resistance. Another approach is to crossbreed American chestnuts with Chinese chestnut trees, which are moderately blight-resistant, and then to backcross with American chestnuts, with the goal of creating a cultivar with most of the genetic heritage of American but retaining the blight resistance of the Chinese chestnut.

🔗 Death 🔗 Italy 🔗 Hungary 🔗 Austria 🔗 Netherlands 🔗 Jewish history

A Stolperstein (pronounced [ˈʃtɔlpɐˌʃtaɪn] (listen); plural Stolpersteine; literally "stumbling stone", metaphorically a "stumbling block") is a sett-size, ten-centimetre (3.9 in) concrete cube bearing a brass plate inscribed with the name and life dates of victims of Nazi extermination or persecution.

The Stolpersteine project, initiated by the German artist Gunter Demnig in 1992, aims to commemorate individuals at exactly the last place of residency—or, sometimes, work—which was freely chosen by the person before he or she fell victim to Nazi terror, euthanasia, eugenics, deportation to a concentration or extermination camp, or escaped persecution by emigration or suicide. As of December 2019, 75,000 Stolpersteine have been laid, making the Stolpersteine project the world's largest decentralized memorial.

The majority of Stolpersteine commemorate Jewish victims of the Holocaust. Others have been placed for Sinti and Romani people (then also called "gypsies"), homosexuals, the physically or mentally disabled, Jehovah's Witnesses, black people, members of the Communist Party, the Social Democratic Party, and the anti-Nazi Resistance, the Christian opposition (both Protestants and Catholics), and Freemasons, along with International Brigade soldiers in the Spanish Civil War, military deserters, conscientious objectors, escape helpers, capitulators, "habitual criminals", looters, and others charged with treason, military disobedience, or undermining the Nazi military, as well as Allied soldiers.

🔗 Amateur radio

The British Amateur Television Club (BATC) is the world's largest television technology club; it has members in the UK and all around the world and is a non-profit making club run by an elected committee of volunteers for the benefit of its members. Membership is open to all who are interested in television, amateur or professional, indeed the club has many members who work for major broadcasting companies.

🔗 Law 🔗 Sexology and sexuality 🔗 Pornography

The Miller test, also called the three-prong obscenity test, is the United States Supreme Court's test for determining whether speech or expression can be labeled obscene, in which case it is not protected by the First Amendment to the United States Constitution and can be prohibited.

🔗 Volcanoes 🔗 Islands 🔗 British Overseas Territories 🔗 Argentina 🔗 South America/South Georgia and the South Sandwich Islands 🔗 South America

South Georgia and the South Sandwich Islands (SGSSI) is a British Overseas Territory in the southern Atlantic Ocean. It is a remote and inhospitable collection of islands, consisting of South Georgia Island and a chain of smaller islands known as the South Sandwich Islands. South Georgia is 165 kilometres (103 mi) long and 35 kilometres (22 mi) wide and is by far the largest island in the territory. The South Sandwich Islands lie about 700 kilometres (430 mi) southeast of South Georgia. The territory's total land area is 3,903 km² (1,507 sq mi). The Falkland Islands are about 1,300 kilometres (810 mi) west from its nearest point.

No permanent native population lives in the South Sandwich Islands, and a very small non-permanent population resides on South Georgia. There are no scheduled passenger flights or ferries to or from the territory, although visits by cruise liners to South Georgia are increasingly popular, with several thousand visitors each summer.

The United Kingdom claimed sovereignty over South Georgia in 1775 and the South Sandwich Islands in 1908. The territory of "South Georgia and the South Sandwich Islands" was formed in 1985; previously, it had been governed as part of the Falkland Islands Dependencies. Argentina claimed South Georgia in 1927 and claimed the South Sandwich Islands in 1938.

Argentina maintained a naval station, Corbeta Uruguay, on Thule Island in the South Sandwich Islands from 1976 until 1982 when it was closed by the Royal Navy. The Argentine claim over South Georgia contributed to the 1982 Falklands War, during which Argentine forces briefly occupied the island. Argentina continues to claim sovereignty over South Georgia and the South Sandwich Islands.

Toothfish are vital to the islands' economy; as a result, Toothfish Day is celebrated on 4 September as a bank holiday in the territory.

🔗 New Zealand

Taumatawhakatangi­hangakoauauotamatea­turipukakapikimaunga­horonukupokaiwhen­uakitanatahu is a hill near Porangahau, south of Waipukurau in southern Hawke's Bay, New Zealand. The height of the hill is 305 metres (1,001 ft). The hill is notable primarily for its unusually long name, which is of Māori origin; it is often shortened to Taumata for brevity. It has gained a measure of fame as it is the longest place name found in any English-speaking country, and possibly the longest place name in the world; according to World Atlas. The name of the hill (with 85 characters) has also been listed in the Guinness World Records as the longest place name. Other versions of the name, including longer ones, are also sometimes used.

🔗 United States History 🔗 Past Political Scandals and Controversies

The Burr conspiracy was a suspected treasonous cabal of US planters, politicians, and army officers in the early 19th century. The alleged cabal was led by Aaron Burr, the former Vice President of the United States (1801–1805). According to the accusations against him, his goal was to create an independent country in the center of North America including the Southwestern United States and parts of Mexico. Burr's version was that he intended to farm 40,000 acres (160 km²) in the Texas Territory which had been leased to him by the Spanish Crown.

President Thomas Jefferson ordered Burr arrested and indicted for treason, despite a lack of firm evidence. Burr's true intentions remain unclear to historians; some claim that he intended to take parts of Texas and the Louisiana Purchase for himself, others, that he intended to conquer Mexico, and yet others, that he planned to conquer most of the North American continent. The number of men backing him is also unclear, with accounts varying from fewer than forty to over seven thousand. He was acquitted of treason, but the trial destroyed his already faltering political career.

🔗 Psychology

The 'doorway effect' or ‘location updating effect’ is a replicable psychological phenomenon characterized by short-term memory loss when passing through a doorway or moving from one location to another. We tend to forget items of recent significance immediately after crossing a boundary and often forget what we were thinking about or planning on doing upon entering a different room. Research suggests that this phenomenon occurs both at literal boundaries (e.g., moving from one room to another via a door) and metaphorical boundaries (e.g., imagining traversing a doorway, or even when moving from one desktop window to another on a computer).

Memory is organized around specific events or episodes, such as attending a lecture or having a family meal, rather than being a continuous stream interrupted by sleep. This organization is called episodic memory, which involves receiving and storing information about events that are temporarily dated, along with their time and place relationships.

Numerous psychological studies have indicated that the external context, including the location where events occur, plays a significant role in how memories are separated. This context helps establish distinctions between different remembered events. Memories of events that happen in the environment we're currently in are easier to access compared to those from different places. As a result, when we experience spatial changes and move to a different location, it can act as a boundary marker that separates and categorizes our continuous flow of memories into distinct segments.