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๐ The Messinian Salinity Crisis
The Messinian Salinity Crisis (MSC), also referred to as the Messinian Event, and in its latest stage as the Lago Mare event, was a geological event during which the Mediterranean Sea went into a cycle of partly or nearly complete desiccation throughout the latter part of the Messinian age of the Miocene epoch, from 5.96 to 5.33 Ma (million years ago). It ended with the Zanclean flood, when the Atlantic reclaimed the basin.
Sediment samples from below the deep seafloor of the Mediterranean Sea, which include evaporite minerals, soils, and fossil plants, show that the precursor of the Strait of Gibraltar closed tight about 5.96 million years ago, sealing the Mediterranean off from the Atlantic. This resulted in a period of partial desiccation of the Mediterranean Sea, the first of several such periods during the late Miocene. After the strait closed for the last time around 5.6 Ma, the region's generally dry climate at the time dried the Mediterranean basin out nearly completely within a thousand years. This massive desiccation left a deep dry basin, reaching 3 to 5ย km (1.9 to 3.1ย mi) deep below normal sea level, with a few hypersaline pockets similar to today's Dead Sea. Then, around 5.5 Ma, less dry climatic conditions resulted in the basin receiving more freshwater from rivers, progressively filling and diluting the hypersaline lakes into larger pockets of brackish water (much like today's Caspian Sea). The Messinian Salinity Crisis ended with the Strait of Gibraltar finally reopening 5.33 Ma, when the Atlantic rapidly filled up the Mediterranean basin in what is known as the Zanclean flood.
Even today, the Mediterranean is considerably saltier than the North Atlantic, owing to its near isolation by the Strait of Gibraltar and its high rate of evaporation. If the Strait of Gibraltar closes again (which is likely to happen in the near future on a geological time scale), the Mediterranean would mostly evaporate in about a thousand years, after which continued northward movement of Africa may obliterate the Mediterranean altogether.
Only the inflow of Atlantic water maintains the present Mediterranean level. When that was shut off sometime between 6.5 to 6 MYBP, net evaporative loss set in at the rate of around 3,300 cubic kilometers yearly. At that rate, the 3.7 million cubic kilometres of water in the basin would dry up in scarcely more than a thousand years, leaving an extensive layer of salt some tens of meters thick and raising global sea level about 12 meters.
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- "The Messinian Salinity Crisis" | 2016-02-22 | 17 Upvotes 4 Comments
๐ Pankration
Pankration (; Greek: ฯฮฑฮณฮบฯฮฌฯฮนฮฟฮฝ) was a sporting event introduced into the Greek Olympic Games in 648 BC and was an empty-hand submission sport with scarcely any rules. The athletes used boxing and wrestling techniques, but also others, such as kicking and holds, locks and chokes on the ground. The term comes from the Greek ฯฮฑฮณฮบฯฮฌฯฮนฮฟฮฝ [paลkrรกtion], literally meaning "all of power" from ฯแพถฮฝ (pan) "all" and ฮบฯฮฌฯฮฟฯ (kratos) "strength, might, power".
It was known in ancient times for its ferocity and allowance of such tactics as knees to the head and eye gouging. One ancient account tells of a situation in which the judges were trying to determine the winner of a match. The difficulty lay in that fact that both men had died in the arena from their injuries, making it hard to determine a victor. Eventually, the judges decided the winner was the one who didn't have his eyes gouged out. Over time, however, maneuvers like eye gouging were discouraged to prevent such unpleasant incidents.
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- "Pankration" | 2015-04-09 | 16 Upvotes 18 Comments
๐ Cairo โ Open-Source 2D Graphics Layer/API with font support and many back-ends
Cairo (stylized as cairo) is an open-source graphics library that provides a vector graphics-based, device-independent API for software developers. It provides primitives for two-dimensional drawing across a number of different back ends. Cairo uses hardware acceleration when available.
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- "Cairo โ Open-Source 2D Graphics Layer/API with font support and many back-ends" | 2023-07-15 | 10 Upvotes 5 Comments
๐ C++0x (upcoming C++ standard, includes lambda functions)
C++11 is a version of the standard for the programming language C++. It was approved by International Organization for Standardization (ISO) on 12 August 2011, replacing C++03, superseded by C++14 on 18 August 2014 and later, by C++17. The name follows the tradition of naming language versions by the publication year of the specification, though it was formerly named C++0x because it was expected to be published before 2010.
Although one of the design goals was to prefer changes to the libraries over changes to the core language, C++11 does make several additions to the core language. Areas of the core language that were significantly improved include multithreading support, generic programming support, uniform initialization, and performance. Significant changes were also made to the C++ Standard Library, incorporating most of the C++ Technical Report 1 (TR1) libraries, except the library of mathematical special functions.
C++11 was published as ISO/IEC 14882:2011 in September 2011 and is available for a fee. The working draft most similar to the published C++11 standard is N3337, dated 16 January 2012; it has only editorial corrections from the C++11 standard.
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- "C++0x (upcoming C++ standard, includes lambda functions)" | 2010-08-11 | 19 Upvotes 25 Comments
๐ Tupper's formula
Tupper's self-referential formula is a formula that visually represents itself when graphed at a specific location in the (x, y) plane.
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- "Tupper's formula" | 2015-04-16 | 92 Upvotes 24 Comments
๐ Palmer Notation
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 (โโฟ โโพ) 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 "โ" underneath it, while the left one would have "โฟ".
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- "Palmer Notation" | 2022-04-07 | 22 Upvotes 4 Comments
๐ Sรคkkijรคrven polkka
Sรคkkijรคrven polkka ("the Sรคkkijรคrvi polka"), also called the "Karelian-Finnish Polka," is a well-known folk tune from Finland, very popular with Finnish accordionists. It was especially popularized by Viljo "Vili" Vesterinen (1907โ1961). The tune was first recorded in Sรคkkijรคrvi (now Kondratyevo in the Leningrad Oblast, Russia), and the lyrics sometimes sung with the tune state that while Sรคkkijรคrvi itself might have been lost (ceded to the Soviet Union in 1940), the Finns at least still had the polka.
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- "Sรคkkijรคrven polkka" | 2020-05-05 | 172 Upvotes 56 Comments
๐ James-Lange Theory
The JamesโLange theory is a hypothesis on the origin and nature of emotions and is one of the earliest theories of emotion within modern psychology. It was developed by philosopher John Dewey and named for two 19th-century scholars, William James and Carl Lange (see modern criticism for more on the theory's origin). The basic premise of the theory is that physiological arousal instigates the experience of emotion. Previously people considered emotions as reactions to some significant events or their features, i.e. events come first, and then there is an emotional response. James-Lange theory proposed that the state of the body can induce emotions or emotional dispositions. In other words, this theory suggests that when we feel teary, it generates a disposition for sad emotions; when our heartbeat is out of normality, it makes us feel anxiety. Instead of feeling an emotion and subsequent physiological (bodily) response, the theory proposes that the physiological change is primary, and emotion is then experienced when the brain reacts to the information received via the body's nervous system. It proposes that each specific category of emotion is attached to a unique and different pattern of physiological arousal and emotional behaviour in reaction due to an exciting stimulus.
The theory has been criticized and modified over the course of time, as one of several competing theories of emotion. Modern theorists have built on its ideas by proposing that the experience of emotion is modulated by both physiological feedback and other information, rather than consisting solely of bodily changes, as James suggested. Psychologist Tim Dalgleish states that most modern affective neuroscientists would support such a viewpoint. In 2002, a research paper on the autonomic nervous system stated that the theory has been "hard to disprove".
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- "James-Lange Theory" | 2023-12-01 | 38 Upvotes 12 Comments
๐ Before Present
Before Present (BP) years is a time scale used mainly in archaeology, geology and other scientific disciplines to specify when events occurred in the past. Because the "present" time changes, standard practice is to use 1 January 1950 as the commencement date (epoch) of the age scale, reflecting the origin of practical radiocarbon dating in the 1950s. The abbreviation "BP" has been interpreted retrospectively as "Before Physics"; that refers to the time before nuclear weapons testing artificially altered the proportion of the carbon isotopes in the atmosphere, making dating after that time likely to be unreliable.
In a convention that is not always observed, many sources restrict the use of BP dates to those produced with radiocarbon dating; the alternative notation RCYBP is explicitly Radio Carbon Years Before Present.
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- "Before Present" | 2018-07-20 | 56 Upvotes 27 Comments
๐ Kugelmugel
Kugelmugel, officially the Republic of Kugelmugel (German: Republik Kugelmugel), is a spherical art object located in Vienna, Austria.
It came about as the result of the artist Edwin Lipburger constructing the 8 meter diameter spherical object without permissions from the authorities in Austria. After the dispute between the artist and authorities, the artist declared it a micronation, and it was eventually granted asylum by the then-mayor Helmut Zilk in Vienna where it is housed in the Prater park.
The 'Republic' is currently administered by Linda Treiber as president.