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🔗 Indigenous peoples of the Americas 🔗 Peru

Quipu (also spelled khipu) are recording devices fashioned from strings historically used by a number of cultures in the region of Andean South America. Knotted strings were used by many other cultures such as the ancient Chinese and native Hawaiians, but such practices should not be confused with the quipu, which refers only to the Andean device.

A quipu usually consisted of cotton or camelid fiber strings. The Inca people used them for collecting data and keeping records, monitoring tax obligations, properly collecting census records, calendrical information, and for military organization. The cords stored numeric and other values encoded as knots, often in a base ten positional system. A quipu could have only a few or thousands of cords. The configuration of the quipus has been "compared to string mops." Archaeological evidence has also shown the use of finely carved wood as a supplemental, and perhaps more sturdy, base to which the color-coded cords would be attached. A relatively small number have survived.

Objects that can be identified unambiguously as quipus first appear in the archaeological record in the first millennium AD. They subsequently played a key part in the administration of the Kingdom of Cusco and later Tawantinsuyu, the empire controlled by the Inca ethnic group, flourishing across the Andes from c. 1100 to 1532 AD. As the region was subsumed under the invading Spanish Empire, the quipu faded from use, to be replaced by European writing and numeral systems. However, in several villages, quipu continued to be important items for the local community, albeit for ritual rather than practical use. It is unclear as to where and how many intact quipus still exist, as many have been stored away in mausoleums.

Quipu is the Spanish spelling and the most common spelling in English. Khipu (pronounced [ˈkʰɪpʊ], plural: khipukuna) is the word for "knot" in Cusco Quechua. In most Quechua varieties, the term is kipu.

🔗 Central Asia 🔗 Oceans 🔗 Lakes 🔗 Central Asia/Kazakhstan 🔗 Central Asia/Uzbekistan

The Aral Sea ( ARR-əl; Kazakh: Арал теңізі, romanized: Aral teñızı; Uzbek: Орол денгизи, romanized: Orol dengizi; Karakalpak: Арал теңизи, romanized: Aral teńizi; Russian: Аральское море, romanized: Aral'skoye more) was an endorheic lake lying between Kazakhstan (Aktobe and Kyzylorda Regions) in the north and Uzbekistan (Karakalpakstan autonomous region) in the south which began shrinking in the 1960s and had largely dried up by the 2010s. The name roughly translates as "Sea of Islands", referring to over 1,100 islands that had dotted its waters. In the Mongolic and Turkic languages aral means "island, archipelago". The Aral Sea drainage basin encompasses Uzbekistan and parts of Tajikistan, Turkmenistan, Kyrgyzstan, Kazakhstan, Afghanistan, and Iran.

Formerly the fourth largest lake in the world with an area of 68,000 km² (26,300 sq mi), the Aral Sea began shrinking in the 1960s after the rivers that fed it were diverted by Soviet irrigation projects. By 1997, it had declined to 10% of its original size, splitting into four lakes: the North Aral Sea, the eastern and western basins of the once far larger South Aral Sea, and the smaller intermediate Barsakelmes Lake.

By 2009, the southeastern lake had disappeared and the southwestern lake had retreated to a thin strip at the western edge of the former southern sea. In subsequent years occasional water flows have led to the southeastern lake sometimes being replenished to a small degree. Satellite images by NASA in August 2014 revealed that for the first time in modern history the eastern basin of the Aral Sea had completely dried up. The eastern basin is now called the Aralkum Desert.

In an ongoing effort in Kazakhstan to save and replenish the North Aral Sea, the Dike Kokaral dam was completed in 2005. By 2008, the water level had risen 12 m (39 ft) above that of 2003. Salinity has dropped, and fish are again present in sufficient numbers for some fishing to be viable. The maximum depth of the North Aral Sea was 42 m (138 ft) (as of 2008).

United Nations Secretary General Ban Ki-moon called the shrinking of the Aral Sea "one of the planet's worst environmental disasters". The region's once-prosperous fishing industry has been devastated, bringing unemployment and economic hardship. The water from the diverted Syr Darya river is used to irrigate about two million hectares (5,000,000 acres) of farmland in the Ferghana Valley. The Aral Sea region is heavily polluted, with consequent serious public health problems. UNESCO has added historical documents concerning the Aral Sea to its Memory of the World Register as a resource to study the environmental tragedy.

🔗 Korea 🔗 China 🔗 East Asia 🔗 Writing systems 🔗 Japan 🔗 Japan/History 🔗 Japan/Culture 🔗 Korea/one or more inactive working groups 🔗 Japan/Education

The Thousand Character Classic (Chinese: 千字文; pinyin: Qiānzì Wén), also known as the Thousand Character Text, is a Chinese poem that has been used as a primer for teaching Chinese characters to children from the sixth century onward. It contains exactly one thousand characters, each used only once, arranged into 250 lines of four characters apiece and grouped into four line rhyming stanzas to make it easy to memorize. It is sung, much as children learning the Latin alphabet sing an "alphabet song." Along with the Three Character Classic and the Hundred Family Surnames, it has formed the basis of literacy training in traditional China.

The first line is Tian di xuan huang (traditional Chinese: 天地玄黃; simplified Chinese: 天地玄黄; pinyin: Tiāndì xuán huáng; Jyutping: tin1 dei6 jyun4 wong4; lit. 'Heaven and Earth Dark and Yellow') and the last line, Yan zai hu ye (焉哉乎也; Yān zāi hū yě; yin1 zoi1 fu4 jaa5) explains the use of the grammatical particles "yan", "zai", "hu", and "ye".

🔗 Film 🔗 Film/Japanese cinema

Ornamental Hairpin (簪, Kanzashi) is a 1941 Japanese comedy-drama film written and directed by Hiroshi Shimizu. It is based on the short story Yottsu no yubune (四つの湯槽, lit. "The four bathtubs") by Masuji Ibuse.

🔗 Biography 🔗 Korea 🔗 Biography/science and academia

Kim Ung-Yong (Hangul: 김웅용; born March 8, 1962) is a South Korean professor and former child prodigy, who once held the Guinness World Record for highest IQ, at a score of 230+.

🔗 Computing 🔗 Mathematics 🔗 Statistics 🔗 Cognitive science

The curse of dimensionality refers to various phenomena that arise when analyzing and organizing data in high-dimensional spaces (often with hundreds or thousands of dimensions) that do not occur in low-dimensional settings such as the three-dimensional physical space of everyday experience. The expression was coined by Richard E. Bellman when considering problems in dynamic programming.

Cursed phenomena occur in domains such as numerical analysis, sampling, combinatorics, machine learning, data mining and databases. The common theme of these problems is that when the dimensionality increases, the volume of the space increases so fast that the available data become sparse. This sparsity is problematic for any method that requires statistical significance. In order to obtain a statistically sound and reliable result, the amount of data needed to support the result often grows exponentially with the dimensionality. Also, organizing and searching data often relies on detecting areas where objects form groups with similar properties; in high dimensional data, however, all objects appear to be sparse and dissimilar in many ways, which prevents common data organization strategies from being efficient.

🔗 Physics 🔗 Chemistry 🔗 Geology 🔗 Rocks and minerals

A quasiperiodic crystal, or quasicrystal, is a structure that is ordered but not periodic. A quasicrystalline pattern can continuously fill all available space, but it lacks translational symmetry. While crystals, according to the classical crystallographic restriction theorem, can possess only two-, three-, four-, and six-fold rotational symmetries, the Bragg diffraction pattern of quasicrystals shows sharp peaks with other symmetry orders—for instance, five-fold.

Aperiodic tilings were discovered by mathematicians in the early 1960s, and, some twenty years later, they were found to apply to the study of natural quasicrystals. The discovery of these aperiodic forms in nature has produced a paradigm shift in the fields of crystallography. Quasicrystals had been investigated and observed earlier, but, until the 1980s, they were disregarded in favor of the prevailing views about the atomic structure of matter. In 2009, after a dedicated search, a mineralogical finding, icosahedrite, offered evidence for the existence of natural quasicrystals.

Roughly, an ordering is non-periodic if it lacks translational symmetry, which means that a shifted copy will never match exactly with its original. The more precise mathematical definition is that there is never translational symmetry in more than n – 1 linearly independent directions, where n is the dimension of the space filled, e.g., the three-dimensional tiling displayed in a quasicrystal may have translational symmetry in two directions. Symmetrical diffraction patterns result from the existence of an indefinitely large number of elements with a regular spacing, a property loosely described as long-range order. Experimentally, the aperiodicity is revealed in the unusual symmetry of the diffraction pattern, that is, symmetry of orders other than two, three, four, or six. In 1982 materials scientist Dan Shechtman observed that certain aluminium-manganese alloys produced the unusual diffractograms which today are seen as revelatory of quasicrystal structures. Due to fear of the scientific community's reaction, it took him two years to publish the results for which he was awarded the Nobel Prize in Chemistry in 2011. On 25 October 2018, Luca Bindi and Paul Steinhardt were awarded the Aspen Institute 2018 Prize for collaboration and scientific research between Italy and the United States.

🔗 United States 🔗 Companies 🔗 Taxation

Companies of the United States with untaxed profits deals with those U.S. companies whose offshore subsidiaries earn profits which are retained in foreign countries to defer paying U.S. corporate tax. The profits of United States corporations are subject to a federal corporate tax rate of 21%. In principle, the tax is payable on all profits of corporations, whether earned domestically or abroad. However, overseas subsidiaries of U.S. corporations are entitled to a tax deferral of profits on active income until repatriated to the U.S., and are regarded as untaxed. When repatriated, the corporations are entitled to a foreign tax credit for taxes (if any) paid in foreign countries.

Retaining such profits offshore may be regarded as a tax strategy. Many corporations have accumulated substantial untaxed profits offshore, especially in countries with low corporate tax rates. In recent years it has been estimated that untaxed profits range from US$1.6 to $2.1 trillion. The Wall Street Journal noted that the "[u]ntaxed foreign earnings are part of a contentious debate over U.S. fiscal policy and tax code." The profits earned abroad and retained there are subject to a foreign exchange risk, besides other financial risks.

The downside of a strategy of retaining profits offshore is that corporations may want or need to pay dividends to shareholders, or to make investments in the United States, besides other reasons. The alternative may be to borrow funds in the U.S., or access the funds retained offshore in the form of inter-company loans.

The Tax Cuts and Jobs Act of 2017 (TCJA) imposed a one time tax on these offshore profits at 8% (non-cash) and 15.5% (cash) respectively. The Act also includes a provision that taxes all foreign profits in the US in the year they are earned ending the ability of US companies to defer paying US tax on unrepatriated earnings.

🔗 Soviet Union 🔗 Socialism 🔗 Latvia 🔗 Estonia 🔗 Soviet Union/history of Russia 🔗 Soviet Union/Russia 🔗 Lithuania

The Baltic Way or Baltic Chain (also Chain of Freedom; Estonian: Balti kett; Latvian: Baltijas ceļš; Lithuanian: Baltijos kelias; Russian: Балтийский путь Baltiysky put) was a peaceful political demonstration that occurred on 23 August 1989. Approximately two million people joined their hands to form a human chain spanning 675.5 kilometres (419.7 mi) across the three Baltic states – Estonia, Latvia, and Lithuania, which were considered at the time to be constituent republics of the Soviet Union.

The demonstration originated in "Black Ribbon Day" protests held in the western cities in the 1980s. It marked the 50th anniversary of the Molotov–Ribbentrop Pact between the Soviet Union and Nazi Germany. The pact and its secret protocols divided Eastern Europe into spheres of influence and led to the occupation of the Baltic states in 1940. The event was organised by Baltic pro-independence movements: Rahvarinne of Estonia, the Tautas fronte of Latvia, and Sąjūdis of Lithuania. The protest was designed to draw global attention by demonstrating a popular desire for independence and showcasing solidarity among the three nations. It has been described as an effective publicity campaign, and an emotionally captivating and visually stunning scene. The event presented an opportunity for the Baltic activists to publicise the Soviet rule and position the question of Baltic independence not only as a political matter, but also as a moral issue. The Soviet authorities responded to the event with intense rhetoric, but failed to take any constructive actions that could bridge the widening gap between the Baltic republics and the rest of the Soviet Union. Within seven months of the protest, Lithuania became the first of the Soviet republics to declare independence.

After the Revolutions of 1989, 23 August has become an official remembrance day both in the Baltic countries, in the European Union and in other countries, known as the Black Ribbon Day or as the European Day of Remembrance for Victims of Stalinism and Nazism.

🔗 United States 🔗 Law

Hush-A-Phone v. United States, 238 F.2d 266 (D.C. Cir. 1956) was a seminal ruling in United States telecommunications decided by the D.C. Circuit Court of Appeals. Hush-A-Phone Corporation marketed a small, cup-like device which mounted on the speaking party's microphone, reducing the risk of conversations being overheard and increasing sound fidelity for the listening party. At the time, AT&T had a near-monopoly on America's phone system, even controlling the equipment attached to its network. In this era, Americans had to lease equipment from "Ma Bell" or use approved devices. At this time Hush-A-Phone had been around for 20 years without any issues. However, when an AT&T lawyer saw one in a store window, the company decided to sue on the grounds that anything attached to a phone could damage their network.

AT&T, citing the Communications Act of 1934, which stated in part that the company had the right to make changes and dictate "the classifications, practices, and regulations affecting such charges," claimed the right to "forbid attachment to the telephone of any device 'not furnished by the telephone company.'"

Initially, the Federal Communications Commission (FCC) ruled in AT&T's favor. It found that the device was a "foreign attachment" subject to AT&T control and that unrestricted use of the device could, in the commission's opinion, result in a general deterioration of the quality of telephone service.