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🔗 Physics 🔗 Soil

The angle of repose, or critical angle of repose, of a granular material is the steepest angle of descent or dip relative to the horizontal plane to which a material can be piled without slumping. At this angle, the material on the slope face is on the verge of sliding. The angle of repose can range from 0° to 90°. The morphology of the material affects the angle of repose; smooth, rounded sand grains cannot be piled as steeply as can rough, interlocking sands. The angle of repose can also be affected by additions of solvents. If a small amount of water is able to bridge the gaps between particles, electrostatic attraction of the water to mineral surfaces will increase the angle of repose, and related quantities such as the soil strength.

When bulk granular materials are poured onto a horizontal surface, a conical pile will form. The internal angle between the surface of the pile and the horizontal surface is known as the angle of repose and is related to the density, surface area and shapes of the particles, and the coefficient of friction of the material. Material with a low angle of repose forms flatter piles than material with a high angle of repose.

The term has a related usage in mechanics, where it refers to the maximum angle at which an object can rest on an inclined plane without sliding down. This angle is equal to the arctangent of the coefficient of static friction μ_s between the surfaces.

🔗 History 🔗 Ancient Near East 🔗 Business 🔗 Iraq

The complaint tablet to Ea-nasir is a clay tablet from ancient Babylon written c. 1750 BC. It is a complaint to a merchant named Ea-Nasir from a customer named Nanni. Written in cuneiform, it is considered to be the oldest known written complaint. It is currently kept in the British Museum.

Ea-Nasir travelled to the Persian Gulf to buy copper and return to sell it in Mesopotamia. On one particular occasion, he had agreed to sell copper ingots to Nanni. Nanni sent his servant with the money to complete the transaction. The copper was sub-standard and not accepted. In response, Nanni created the cuneiform letter for delivery to Ea-nasir. Inscribed on it is a complaint to Ea-nasir about a copper ore delivery of the incorrect grade, and issues with another delivery. He also complained that his servant (who handled the transaction) had been treated rudely. He stated that, at the time of writing, he had not accepted the copper but had paid the money.

The tablet is 11.6 centimetres (4.6 in) high, 5 centimetres (2.0 in) wide, 2.6 centimetres (1.0 in) thick, and slightly damaged. Translated from Akkadian, it reads:

Tell Ea-nasir: Nanni sends the following message:

When you came, you said to me as follows : "I will give Gimil-Sin (when he comes) fine quality copper ingots." You left then but you did not do what you promised me. You put ingots which were not good before my messenger (Sit-Sin) and said: "If you want to take them, take them; if you do not want to take them, go away!"

What do you take me for, that you treat somebody like me with such contempt? I have sent as messengers gentlemen like ourselves to collect the bag with my money (deposited with you) but you have treated me with contempt by sending them back to me empty-handed several times, and that through enemy territory. Is there anyone among the merchants who trade with Telmun who has treated me in this way? You alone treat my messenger with contempt! On account of that one (trifling) mina of silver which I owe(?) you, you feel free to speak in such a way, while I have given to the palace on your behalf 1,080 pounds of copper, and Šumi-abum has likewise given 1,080 pounds of copper, apart from what we both have had written on a sealed tablet to be kept in the temple of Shamash.

How have you treated me for that copper? You have withheld my money bag from me in enemy territory; it is now up to you to restore (my money) to me in full.

Take cognizance that (from now on) I will not accept here any copper from you that is not of fine quality. I shall (from now on) select and take the ingots individually in my own yard, and I shall exercise against you my right of rejection because you have treated me with contempt.

The tablet was acquired by the British Museum in 1953. It was originally found in the ruins of Ur.

🔗 Russia 🔗 Dogs 🔗 Russia/science and education in Russia 🔗 Genetics

The domesticated silver fox is a form of the silver fox that has been to some extent domesticated under laboratory conditions. The silver fox is a melanistic form of the wild red fox. Domesticated silver foxes are the result of an experiment designed to demonstrate the power of selective breeding to transform species, as described by Charles Darwin in On the Origin of Species. The experiment at the Institute of Cytology and Genetics in Novosibirsk, Siberia explored whether selection for behaviour rather than morphology may have been the process that had produced dogs from wolves, by recording the changes in foxes when in each generation only the most tame foxes were allowed to breed. Many of the descendant foxes became both tamer and more dog-like in morphology, including displaying mottled or spotted coloured fur.

In 2019, an international research team questioned the conclusion that this experiment had provided strong support for the validity of domestication syndrome. They did conclude that it remains "a resource for investigation of the genomics and biology of behavior".

🔗 Mathematics

A prime number (or a prime) is a natural number greater than 1 that cannot be formed by multiplying two smaller natural numbers. A natural number greater than 1 that is not prime is called a composite number. For example, 5 is prime because the only ways of writing it as a product, 1 × 5 or 5 × 1, involve 5 itself. However, 6 is composite because it is the product of two numbers (2 × 3) that are both smaller than 6. Primes are central in number theory because of the fundamental theorem of arithmetic: every natural number greater than 1 is either a prime itself or can be factorized as a product of primes that is unique up to their order.

The property of being prime is called primality. A simple but slow method of checking the primality of a given number ${\displaystyle n}$, called trial division, tests whether ${\displaystyle n}$ is a multiple of any integer between 2 and ${\displaystyle {\sqrt {n}}}$. Faster algorithms include the Miller–Rabin primality test, which is fast but has a small chance of error, and the AKS primality test, which always produces the correct answer in polynomial time but is too slow to be practical. Particularly fast methods are available for numbers of special forms, such as Mersenne numbers. As of December 2018 the largest known prime number has 24,862,048 decimal digits.

There are infinitely many primes, as demonstrated by Euclid around 300 BC. No known simple formula separates prime numbers from composite numbers. However, the distribution of primes within the natural numbers in the large can be statistically modelled. The first result in that direction is the prime number theorem, proven at the end of the 19th century, which says that the probability of a randomly chosen number being prime is inversely proportional to its number of digits, that is, to its logarithm.

Several historical questions regarding prime numbers are still unsolved. These include Goldbach's conjecture, that every even integer greater than 2 can be expressed as the sum of two primes, and the twin prime conjecture, that there are infinitely many pairs of primes having just one even number between them. Such questions spurred the development of various branches of number theory, focusing on analytic or algebraic aspects of numbers. Primes are used in several routines in information technology, such as public-key cryptography, which relies on the difficulty of factoring large numbers into their prime factors. In abstract algebra, objects that behave in a generalized way like prime numbers include prime elements and prime ideals.

🔗 Film 🔗 Lists 🔗 European Microstates 🔗 European Microstates/Vatican City

In 1995, on the occasion of the 100th anniversary of cinema, the Vatican compiled a list of 45 "great films". The 45 movies are divided into three categories: religion, values, and art.

🔗 Computing

The Owner-Free File System (OFF System, or OFF for short) is a peer-to-peer distributed file system in which all shared files are represented by randomized multi-used data blocks. Instead of anonymizing the network, the data blocks are anonymized and therefore, only data garbage is ever exchanged and stored and no forwarding via intermediate nodes is required. OFF claims to have been created with the expressed intention "to cut off some gangrene-infested bits of the copyright industry."

🔗 Environment 🔗 Architecture 🔗 Civil engineering 🔗 Industrial design

Biophilic design is a concept used within the building industry to increase occupant connectivity to the natural environment through the use of direct nature, indirect nature, and space and place conditions. Used at both the building and city-scale, it is argued that this idea has health, environmental, and economic benefits for building occupants and urban environments, with few drawbacks. Although its name was coined in recent history, indicators of biophilic design have been seen in architecture from as far back as the Hanging Gardens of Babylon.

🔗 United States 🔗 Law 🔗 Women's History 🔗 LGBT studies 🔗 Virginia 🔗 African diaspora 🔗 Civil Rights Movement 🔗 U.S. Supreme Court cases

Loving v. Virginia, 388 U.S. 1 (1967), was a landmark civil rights decision of the U.S. Supreme Court in which the Court ruled that laws banning interracial marriage violate the Equal Protection and Due Process Clauses of the Fourteenth Amendment to the U.S. Constitution. Beginning in 2013, it was cited as precedent in U.S. federal court decisions holding restrictions on same-sex marriage in the United States unconstitutional, including in the 2015 Supreme Court decision Obergefell v. Hodges.

The case involved Mildred Loving, a woman of color, and her white husband Richard Loving, who in 1958 were sentenced to a year in prison for marrying each other. Their marriage violated Virginia's Racial Integrity Act of 1924, which criminalized marriage between people classified as "white" and people classified as "colored". The Lovings appealed their conviction to the Supreme Court of Virginia, which upheld it. They then appealed to the U.S. Supreme Court, which agreed to hear their case.

In June 1967, the Supreme Court issued a unanimous decision in the Lovings' favor and overturned their convictions. Its decision struck down Virginia's anti-miscegenation law and ended all race-based legal restrictions on marriage in the United States. Virginia had argued that its law was not a violation of the Equal Protection Clause because the punishment was the same regardless of the offender's race, and thus it "equally burdened" both whites and non-whites. The Court found that the law nonetheless violated the Equal Protection Clause because it was based solely on "distinctions drawn according to race" and outlawed conduct—namely, getting married—that was otherwise generally accepted and which citizens were free to do.

🔗 Biography 🔗 Internet 🔗 Computing 🔗 Philosophy 🔗 Biography/science and academia 🔗 Philosophy/Philosophers 🔗 Sociology 🔗 University of Oxford

Theodor Holm Nelson (born June 17, 1937) is an American pioneer of information technology, philosopher and sociologist. He coined the terms hypertext and hypermedia in 1963 and published them in 1965. Nelson coined the terms transclusion, virtuality, and intertwingularity (in Literary Machines), and teledildonics. According to a 1997 Forbes profile, Nelson "sees himself as a literary romantic, like a Cyrano de Bergerac, or 'the Orson Welles of software.'"

🔗 Russia 🔗 Military history 🔗 Geography 🔗 Poland 🔗 Lithuania 🔗 Military history/Russian, Soviet and CIS military history 🔗 Military history/Polish military history 🔗 Military history/European military history 🔗 Belarus 🔗 NATO

The Suwałki Gap, also known as the Suwałki corridor ([suˈvawkʲi] (listen)), is a sparsely populated area immediately southwest of the border between Lithuania and Poland, between Belarus and the Russian exclave of Kaliningrad Oblast. Named after the Polish town of Suwałki, this choke point has become of great strategic and military importance since Poland and the Baltic states joined the North Atlantic Treaty Organization (NATO).

The border between Poland and Lithuania was formed after the Suwałki Agreement of 1920; but it carried little importance in the interwar period as at the time, the Polish lands stretched farther northeast, while during the Cold War, Lithuania was part of the Soviet Union and communist Poland belonged to the Soviet-led Warsaw Pact alliance. The dissolution of the Soviet Union and the Warsaw Pact created borders that cut through the shortest land route between Kaliningrad (Russian territory isolated from the mainland) and Belarus (Russia's ally). As the Baltic states and Poland eventually joined NATO, this narrow border stretch between Poland and Lithuania became a vulnerability for the military bloc because, if a hypothetical military conflict were to erupt between Russia and Belarus on one side and NATO on the other, the capture of the 65 km (40 mi)-long strip of land between Russia's Kaliningrad Oblast and Belarus would likely jeopardise NATO's attempts to defend the Baltic states. NATO's fears about the Suwałki Gap intensified after 2014, when Russia annexed Crimea and launched the war in Donbas, and further increased after Russia invaded Ukraine in February 2022. These worries prompted the alliance to increase its military presence in the area, and an arms race was triggered by these events.

Both Russia and the European Union countries also saw great interest in civilian uses of the gap. In the 1990s and early 2000s, Russia attempted to negotiate an extraterritorial corridor to connect its exclave of Kaliningrad Oblast with Grodno in Belarus, but Poland, Lithuania and the EU did not consent. Movement of goods through the gap was disrupted in summer 2022, during the Russian invasion of Ukraine, as Lithuania and the European Union introduced transit restrictions on Russian vehicles as part of their sanctions. The Via Baltica road, a vital link connecting Finland and the Baltic states with the rest of the European Union, goes through the area and, as of November 2022, is under construction in Poland as expressway S61.