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Uranium can be extracted from seawater in useful amounts

Energy Mining

Uranium mining is the process of extraction of uranium ore from the ground. The worldwide production of uranium in 2019 amounted to 53,656 tonnes. Kazakhstan, Canada, and Australia were the top three uranium producers, respectively, and together account for 68% of world production. Other countries producing more than 1,000 tonnes per year included Namibia, Niger, Russia, Uzbekistan, the United States, and China. Nearly all of the world's mined uranium is used to power nuclear power plants.

Uranium is mined by in-situ leaching (57% of world production) or by conventional underground or open-pit mining of ores (43% of production). During in-situ mining, a leaching solution is pumped down drill holes into the uranium ore deposit where it dissolves the ore minerals. The uranium-rich fluid is then pumped back to the surface and processed to extract the uranium compounds from solution. In conventional mining, ores are processed by grinding the ore materials to a uniform particle size and then treating the ore to extract the uranium by chemical leaching. The milling process commonly yields dry powder-form material consisting of natural uranium, "yellowcake," which is sold on the uranium market as U3O8.

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Ant mill

Insects Insects/Ant

An ant mill is an observed phenomenon in which a group of army ants are separated from the main foraging party, lose the pheromone track and begin to follow one another, forming a continuously rotating circle, commonly known as a "death spiral" because the ants might eventually die of exhaustion. It has been reproduced in laboratories and has been produced in ant colony simulations. The phenomenon is a side effect of the self-organizing structure of ant colonies. Each ant follows the ant in front of it, which works until a slight deviation begins to occur, typically by an environmental trigger, and an ant mill forms. An ant mill was first described in 1921 by William Beebe, who observed a mill 1200 ft (~370 m) in circumference. It took each ant 2.5 hours to make one revolution. Similar phenomena have been noted in processionary caterpillars and fish.

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Land Value Tax

Economics Taxation

A land value tax (LVT) is a levy on the value of land without regard to buildings, personal property and other improvements. It is also known as a location value tax, a site valuation tax, split rate tax, or a site-value rating,

Land value taxes are generally favored by economists as they do not cause economic inefficiency, and reduce inequality. A land value tax is a progressive tax, in that the tax burden falls on land owners, because land ownership is correlated with wealth and income. The land value tax has been referred to as "the perfect tax" and the economic efficiency of a land value tax has been accepted since the eighteenth century. Economists since Adam Smith and David Ricardo have advocated this tax because it does not hurt economic activity or discourage or subsidize development.

LVT is associated with Henry George, whose ideology became known as Georgism. George argued that taxing the land value is most logical source of public revenue because the supply of land is fixed and because public infrastructure improvements would be reflected in (and thus paid for) by increased land values.

Land value taxation is currently implemented throughout Denmark, Estonia, Lithuania, Russia, Singapore, and Taiwan; it has also been applied to lesser extents in parts of Australia, Mexico (Mexicali), and the United States (e.g., Pennsylvania).

A graph is moral if two nodes that have a common child are married

Computing Mathematics Statistics Robotics

In graph theory, a moral graph is used to find the equivalent undirected form of a directed acyclic graph. It is a key step of the junction tree algorithm, used in belief propagation on graphical models.

The moralized counterpart of a directed acyclic graph is formed by adding edges between all pairs of non-adjacent nodes that have a common child, and then making all edges in the graph undirected. Equivalently, a moral graph of a directed acyclic graph G is an undirected graph in which each node of the original G is now connected to its Markov blanket. The name stems from the fact that, in a moral graph, two nodes that have a common child are required to be married by sharing an edge.

Moralization may also be applied to mixed graphs, called in this context "chain graphs". In a chain graph, a connected component of the undirected subgraph is called a chain. Moralization adds an undirected edge between any two vertices that both have outgoing edges to the same chain, and then forgets the orientation of the directed edges of the graph.

The Trundle

Military history Military history/Fortifications Archaeology Military history/European military history Military history/British military history Sussex

The Trundle is an Iron Age hillfort on St Roche's Hill about 4 miles (6 km) north of Chichester, Sussex, England, built on the site of a causewayed enclosure, a form of early Neolithic earthwork found in northwestern Europe. Causewayed enclosures were built in England from shortly before 3700 BC until about 3300 BC; they are characterized by the full or partial enclosure of an area with ditches that are interrupted by gaps, or causeways. Their purpose is not known; they may have been settlements, meeting places, or ritual sites. Hillforts were built as early as 1000 BC, in the Late Bronze Age, and continued to be built through the Iron Age until shortly before the Roman occupation. A chapel dedicated to St Roche was built on the hill around the end of the 14th century; it was in ruins by 1570. A windmill and a beacon were subsequently built on the hill. The site was occasionally used as a meeting place in the post-medieval period.

The hillfort is still a substantial earthwork, but the Neolithic site was unknown until 1925 when archaeologist O.G.S. Crawford obtained an aerial photograph of the Trundle, clearly showing additional structures inside the ramparts of the hillfort. Causewayed enclosures were new to archaeology at the time, with only five known by 1930, and the photograph persuaded archaeologist E. Cecil Curwen to excavate the site in 1928 and 1930. These early digs established a construction date of about 500 BC to 100 BC for the hillfort and proved the existence of the Neolithic site. In 2011, the Gathering Time project published an analysis of radiocarbon dates from almost forty British causewayed enclosures, including some from the Trundle. The conclusion was that the Neolithic part of the site was probably constructed no earlier than the mid-fourth millennium BC. A review of the site in 1995 by Alastair Oswald noted the presence of fifteen possible Iron Age house platforms within the hillfort's ramparts.

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Volcanic Winter

Environment Volcanoes Geology Weather Weather/Non-tropical storms

A volcanic winter is a reduction in global temperatures caused by volcanic ash and droplets of sulfuric acid and water obscuring the Sun and raising Earth's albedo (increasing the reflection of solar radiation) after a large, particularly explosive volcanic eruption. Long-term cooling effects are primarily dependent upon injection of sulfur gases into the stratosphere where they undergo a series of reactions to create sulfuric acid which can nucleate and form aerosols. Volcanic stratospheric aerosols cool the surface by reflecting solar radiation and warm the stratosphere by absorbing terrestrial radiation. The variations in atmospheric warming and cooling result in changes in tropospheric and stratospheric circulation.

Curse of the Colonel

Japan Paranormal Baseball Japan/Japanese baseball Japan/Mythology

The Curse of the Colonel (Japanese: カーネルサンダースの呪い, romanisation: Kāneru Sandāsu no Noroi) refers to a 1985 Japanese urban legend regarding a reputed curse placed on the Japanese Kansai-based Hanshin Tigers baseball team by the ghost of deceased KFC founder and mascot Colonel Sanders.

The curse was said to be placed on the team because of the Colonel's anger over treatment of one of his store-front statues, which was thrown into the Dōtonbori River by celebrating Hanshin fans before their team's victory in the 1985 Japan Championship Series. As is common with sports-related curses, the Curse of the Colonel was used to explain the team's subsequent 18-year losing streak. Some fans believed the team would never win another Japan Series until the statue had been recovered. They have appeared in the Japan Series three times since then, losing in 2003, 2005 and 2014.

Comparisons are often made between the Hanshin Tigers and the Boston Red Sox, who were said to be under the Curse of the Bambino until they won the World Series in 2004. The "Curse of the Colonel" has also been used as a bogeyman threat to those who would divulge the secret recipe of eleven herbs and spices that result in the unique taste of his chicken.

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Fifty Cent Party

Internet China

50 Cent Party, 50 Cent Army and wumao ( WOO-mow) are terms for Internet commentators who are hired by the authorities of the People's Republic of China to manipulate public opinion and disseminate disinformation to the benefit of the governing Chinese Communist Party (CCP). It was created during the early phases of the Internet's rollout to the wider public in China.

The name is derived from the allegation that such commentators are paid RMB¥0.50 for every post. These commentators create comments or articles on popular Chinese social media networks that are intended to derail discussions which are critical of the CCP, promoting narratives that serve the government's interests and insulting or spreading misinformation about political opponents of the Chinese government, both domestic and abroad. Some of these commentators have labeled themselves ziganwu (Chinese: 自干五, short for 自带干粮的五毛, lit.'wumao who bring their own dry rations'), claiming they are not paid by authorities and express their support for the Chinese government out of their own volition.

Authors of a paper published in 2017 in the American Political Science Review estimate that the Chinese government fabricates 488 million social media posts per year. In contrast to common assumptions, the 50 Cent Party consists mostly of paid bureaucrats who respond to government directives and rarely defend their government from criticism or engage in direct arguments because "... the goal of this massive secretive operation is instead to distract the public and change the subject." Around 80% of the analysed posts involve pro-China cheerleading with inspirational slogans, and 13% involve general praise and suggestions on governmental policies. Despite the common allegation of the commentators getting paid for their posts, the paper suggested there was "no evidence" that they are paid anything for their posts, instead being required to do so as a part of their official party duties.

Research by professors at Harvard, Stanford, and UC San Diego indicated a "massive secretive operation" to fill China's Internet with propaganda, and has resulted in some 488 million posts written by fake social media accounts, representing about 0.6% of the 80 billion posts generated on Chinese social media. To maximize their influence, such pro-government comments are made largely during times of intense online debate, and when online protests have a possibility of transforming into real life actions. The colloquial term wumao has also been used by some English speakers outside of China as an insult against people with perceived pro-CCP bias.

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Cyclorama

Visual arts

A cyclorama is a panoramic image on the inside of a cylindrical platform, designed to give viewers standing in the middle of the cylinder a 360° view, and also a building designed to show a panoramic image. The intended effect is to make viewers, surrounded by the panoramic image, feel as if they were standing in the midst of the place depicted in the image.

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Fluoroantimonic Acid

Chemicals

Fluoroantimonic acid is a mixture of hydrogen fluoride and antimony pentafluoride, containing various cations and anions (the simplest being H
2
F+
and SbF
6
). This substance is a superacid that can be excess of a quadrillion times stronger than 100% pure sulfuric acid, depending on proportion of its ingredients. It has been shown to protonate even hydrocarbons to afford pentacoordinate carbocations (carbonium ions). Extreme caution needs to be in place when handling fluoroantimonic acid. It is exceptionally corrosive, but can be stored in containers lined with PTFE (Teflon).

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