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🔗 China 🔗 Food and drink 🔗 Plants 🔗 Taiwan

Celtuce () (Lactuca sativa var. augustana, angustata, or asparagina), also called stem lettuce, celery lettuce, asparagus lettuce, or Chinese lettuce, is a cultivar of lettuce grown primarily for its thick stem or its leaves, which are known as A-choy. It is used as a vegetable. In China, the family is informally called woju (traditional Chinese: 萵苣; simplified Chinese: 莴苣; pinyin: wōjù), which is also the name of a cultivar. It is especially popular in both China and Taiwan, where the stem is interchangeably called wosun (traditional Chinese: 萵筍; simplified Chinese: 莴笋; pinyin: wōsǔn) or qingsun(青筍; 青笋; qīngsǔn).

🔗 Physics 🔗 Geology 🔗 Physics/Acoustics

Singing sand, also called whistling sand, barking sand or singing dune, is sand that produces sound. The sound emission may be caused by wind passing over dunes or by walking on the sand.

Certain conditions have to come together to create singing sand:

1. The sand grains have to be round and between 0.1 and 0.5 mm in diameter.
2. The sand has to contain silica.
3. The sand needs to be at a certain humidity.

The most common frequency emitted seems to be close to 450 Hz.

There are various theories about the singing sand mechanism. It has been proposed that the sound frequency is controlled by the shear rate. Others have suggested that the frequency of vibration is related to the thickness of the dry surface layer of sand. The sound waves bounce back and forth between the surface of the dune and the surface of the moist layer, creating a resonance that increases the sound's volume. The noise may be generated by friction between the grains or by the compression of air between them.

Other sounds that can be emitted by sand have been described as "roaring" or "booming".

🔗 Dentistry

Palmer notation (sometimes called the "Military System" and named for 19th-century American dentist Dr. Corydon Palmer from Warren, Ohio) is a dental notation (tooth numbering system). Despite the adoption of the FDI World Dental Federation notation (ISO 3950) in most of the world and by the World Health Organization, the Palmer notation continued to be the overwhelmingly preferred method used by orthodontists, dental students and practitioners in the United Kingdom as of 1998.

The notation was originally termed the Zsigmondy system after Hungarian dentist Adolf Zsigmondy, who developed the idea in 1861 using a Zsigmondy cross to record quadrants of tooth positions. Adult teeth were numbered 1 to 8, and the child primary dentition (also called deciduous, milk or baby teeth) were depicted with a quadrant grid using Roman numerals I, II, III, IV, V to number the teeth from the midline. Palmer changed this to A, B, C, D, E, which made it less confusing and less prone to errors in interpretation.

The Palmer notation consists of a symbol (⏌⎿ ⏋⎾) designating in which quadrant the tooth is found and a number indicating the position from the midline. Adult teeth are numbered 1 to 8, with deciduous (baby) teeth indicated by a letter A to E. Hence the left and right maxillary central incisor would have the same number, "1", but the right one would have the symbol "⏌" underneath it, while the left one would have "⎿".

🔗 China 🔗 Economics

Made in China 2025 (Chinese: 中国制造2025; pinyin: Zhōngguózhìzào èrlíng'èrwǔ) (MIC25, MIC 2025, or MIC2025) is a national strategic plan and industrial policy of the Chinese Communist Party (CCP) to further develop the manufacturing sector of China, issued by CCP general secretary Xi Jinping and Chinese Premier Li Keqiang's cabinet in May 2015. As part of the Thirteenth and Fourteenth Five-year Plans, China aims to move away from being the "world's factory"—a producer of cheap low-tech goods facilitated by lower labour costs and supply chain advantages. The industrial policy aims to upgrade the manufacturing capabilities of Chinese industries, growing from labor-intensive workshops into a more technology-intensive powerhouse.

Made in China 2025's goals include increasing the Chinese-domestic content of core materials to 40 percent by 2020 and 70 percent by 2025. To help achieve independence from foreign suppliers, the initiative encourages increased production in high-tech products and services, with its semiconductor industry central to the industrial plan, partly because advances in chip technology may "lead to breakthroughs in other areas of technology, handing the advantage to whoever has the best chips – an advantage that currently is out of Beijing’s reach."

Since 2018, following a backlash from the U.S., Europe, and elsewhere, the phrase "MIC 2025" has been de-emphasized in government and other official communications, while the program remains in place. The Chinese government continues to invest heavily in identified technologies. In 2018, the Chinese government committed to investing roughly US$300 billion into achieving the industrial plan. In the wake of the COVID-19 pandemic, at least an additional $1.4 trillion was also invested into MIC 2025 initiatives. Given China's current middle income country status, the practicality of its disproportionate expenditure on pioneering new technologies has been called into question.

🔗 Chemicals 🔗 Dentistry

Tin(II) fluoride, commonly referred to commercially as stannous fluoride (from Latin stannum, 'tin'), is a chemical compound with the formula SnF₂. It is a colourless solid used as an ingredient in toothpastes.

🔗 Military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/Weaponry 🔗 Middle Ages 🔗 Middle Ages/History 🔗 Military history/Medieval warfare

A rondel dagger or roundel dagger was a type of stiff-bladed dagger in Europe in the late Middle Ages (from the 14th century onwards), used by a variety of people from merchants to knights. It was worn at the waist and might be used as a utility tool, or worn into battle or in a jousting tournament as a side arm.

The rondel dagger featured a long, slim steel blade with a round or circular hand guard and pommel. Designed for close-quarter combat, it was effective in puncturing and bursting mail armor links and penetrating weak points in plate armor. The dagger evolved from the early knightly dagger and became the standard side-arm for knights in the 15th century. It was used as a backup weapon for hand-to-hand fighting and as a tool to force surrender, as captured knights could be ransomed. The rondel dagger also gained popularity among the middle class in the 15th century. Various combat techniques involving the rondel dagger can be found in Hans Talhoffer's combat manuals from the 1440s to 1460s.

🔗 Mass surveillance 🔗 Film 🔗 Germany 🔗 Film/American cinema 🔗 Film/German cinema

The Lives of Others (German: Das Leben der Anderen, pronounced [das ˈleːbm̩ deːɐ̯ ˈʔandəʁən] ) is a 2006 German drama film written and directed by Florian Henckel von Donnersmarck marking his feature film directorial debut. The plot is about the monitoring of East Berlin residents by agents of the Stasi, East Germany's secret police. It stars Ulrich Mühe as Stasi Captain Gerd Wiesler, Ulrich Tukur as his superior Anton Grubitz, Sebastian Koch as the playwright Georg Dreyman, and Martina Gedeck as Dreyman's lover, a prominent actress named Christa-Maria Sieland.

The film was released by Buena Vista International in Germany on 23 March 2006. At the same time, the screenplay was published by Suhrkamp Verlag. The Lives of Others won the Academy Award for Best International Feature Film. The film had earlier won seven Deutscher Filmpreis awards—including those for best film, best director, best screenplay, best actor, and best supporting actor—after setting a new record with 11 nominations. It also won the BAFTA Award for Best Film Not in the English Language and European Film Award for Best Film, while it was nominated for the Golden Globe Award for Best Foreign Language Film. The Lives of Others cost US$2 million and grossed more than US$77 million worldwide.

Released 17 years after the fall of the Berlin Wall, marking the end of the German Democratic Republic, it was the first notable drama film about the subject after a series of comedies such as Good Bye, Lenin! and Sonnenallee. This approach was widely applauded in Germany, and the film was complimented for its accurate tone despite some criticism that Wiesler's character was depicted unrealistically and with undue sympathy. The film's authenticity was considered praiseworthy given that the director grew up outside of East Germany and was 16 when the Berlin Wall fell.

🔗 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".

🔗 Biography 🔗 Mathematics 🔗 Biography/science and academia 🔗 Astronomy 🔗 Linguistics 🔗 Linguistics/Applied Linguistics 🔗 Indigenous peoples of North America 🔗 University of Oxford

Thomas Harriot (Oxford, c. 1560 – London, 2 July 1621), also spelled Harriott, Hariot or Heriot, was an English astronomer, mathematician, ethnographer and translator who made advances within the scientific field. Thomas Harriot was recognized for his contributions in astronomy, mathematics, and navigational techniques. Harriot worked closely with John White to create advanced maps for navigation. While Harriot worked extensively on numerous papers on the subjects of astronomy, mathematics, and navigation the amount of work that was actually published was sparse. So sparse that the only publication that has been produced by Harriot was The Briefe and True Report of the New Found Land of Virginia. The premise of the book includes descriptions of English settlements and financial issues in Virginia at the time. He is sometimes credited with the introduction of the potato to the British Isles. Harriot was the first person to make a drawing of the Moon through a telescope, on 26 July 1609, over four months before Galileo Galilei.

After graduating from St Mary Hall, Oxford, Harriot travelled to the Americas, accompanying the 1585 expedition to Roanoke island funded by Sir Walter Raleigh and led by Sir Ralph Lane. Harriot was a vital member of the venture, having learned and translating the Carolina Algonquian language from two Native Americans: Wanchese and Manteo. On his return to England, he worked for the 9th Earl of Northumberland. At the Earl's house, he became a prolific mathematician and astronomer to whom the theory of refraction is attributed.

🔗 United States/U.S. Government 🔗 United States 🔗 Law 🔗 Open

Patentleft (also patent left, copyleft-style patent license or open patent) is the practice of licensing patents (especially biological patents) for royalty-free use, on the condition that adopters license related improvements they develop under the same terms. Copyleft-style licensors seek "continuous growth of a universally accessible technology commons" from which they, and others, will benefit.

Patentleft is analogous to copyleft, a license which allows distribution of a copyrighted work and derived works, but only under the same or equivalent terms.