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๐Ÿ”— Denรฉโ€“Yeniseian Languages

๐Ÿ”— Russia ๐Ÿ”— Linguistics ๐Ÿ”— Russia/demographics and ethnography of Russia ๐Ÿ”— Languages ๐Ÿ”— Indigenous peoples of North America ๐Ÿ”— Russia/language and literature of Russia

Denรฉโ€“Yeniseian is a proposed language family consisting of the Yeniseian languages of central Siberia and the Na-Denรฉ languages of northwestern North America.

Reception among experts has been largely, though not universally, favorable; thus, Denรฉโ€“Yeniseian has been called "the first demonstration of a genealogical link between Old World and New World language families that meets the standards of traditional comparative-historical linguistics," besides the Eskimoโ€“Aleut languages spoken in far eastern Siberia and North America.

๐Ÿ”— Tendril perversion โ€“ spontaneous symmetry breaking, uncoiling helical structures

๐Ÿ”— Mathematics ๐Ÿ”— Biology ๐Ÿ”— Physics ๐Ÿ”— Plants

Tendril perversion, often referred to in context as simply perversion, is a geometric phenomenon found in helical structures such as plant tendrils, in which a helical structure forms that is divided into two sections of opposite chirality, with a transition between the two in the middle. A similar phenomenon can often be observed in kinked helical cables such as telephone handset cords.

The phenomenon was known to Charles Darwin, who wrote in 1865,

A tendril ... invariably becomes twisted in one part in one direction, and in another part in the opposite direction... This curious and symmetrical structure has been noticed by several botanists, but has not been sufficiently explained.

The term "tendril perversion" was coined by Goriely and Tabor in 1998 based on the word perversion found in the 19th Century science literature. "Perversion" is a transition from one chirality to another and was known to James Clerk Maxwell, who attributed it to the topologist J. B. Listing.

Tendril perversion can be viewed as an example of spontaneous symmetry breaking, in which the strained structure of the tendril adopts a configuration of minimum energy while preserving zero overall twist.

Tendril perversion has been studied both experimentally and theoretically. Gerbode et al. have made experimental studies of the coiling of cucumber tendrils. A detailed study of a simple model of the physics of tendril perversion was made by MacMillen and Goriely in the early 2000s. Liu et al. showed in 2014 that "the transition from a helical to a hemihelical shape, as well as the number of perversions, depends on the height to width ratio of the strip's cross-section."

Generalized tendril perversions were put forward by Silva et al., to include perversions that can be intrinsically produced in elastic filaments, leading to a multiplicity of geometries and dynamical properties.

๐Ÿ”— Children of Men

๐Ÿ”— Film ๐Ÿ”— Film/American cinema ๐Ÿ”— Science Fiction ๐Ÿ”— Romania ๐Ÿ”— Film/British cinema ๐Ÿ”— Film/War films

Children of Men is a 2006 dystopian action thriller film co-written and directed by Alfonso Cuarรณn. The screenplay, based on P. D. James' 1992 novel The Children of Men, was credited to five writers, with Clive Owen making uncredited contributions. The film takes place in 2027, when two decades of human infertility have left society on the brink of collapse. Asylum seekers seek sanctuary in the United Kingdom, where they are subjected to detention and refoulement by the government. Owen plays civil servant Theo Faron, who must help refugee Kee (Clare-Hope Ashitey) escape the chaos. Children of Men also stars Julianne Moore, Chiwetel Ejiofor, Pam Ferris, Charlie Hunnam, and Michael Caine.

The film was released by Universal Pictures on 22 September 2006 in the UK and on 25 December in the US. Critics noted the relationship between the US' Christmas opening and the film's themes of hope, redemption, and faith. Despite the limited release and lack of any clear marketing strategy during awards season by the film's distributor, Children of Men received critical acclaim and was recognised for its achievements in screenwriting, cinematography, art direction, and innovative single-shot action sequences. It was nominated for three Academy Awards: Best Adapted Screenplay, Best Cinematography, and Best Film Editing. It was also nominated for three BAFTA Awards, winning Best Cinematography and Best Production Design, and for three Saturn Awards, winning Best Science Fiction Film. In 2016 it was voted 13th among 100 films considered the best of the 21st century by 117 film critics from around the world.

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๐Ÿ”— Albert Stevens

๐Ÿ”— Biography

Albert Stevens (1887โ€“1966), also known as patient CAL-1, was a victim of a human radiation experiment, and survived the highest known accumulated radiation dose in any human. On May 14, 1945, he was injected with 131 kBq (3.55 ยตCi) of plutonium without his knowledge or informed consent.

Plutonium remained present in his body for the remainder of his life, the amount decaying slowly through radioactive decay and biological elimination. Stevens died of heart disease some 20 years later, having accumulated an effective radiation dose of 64 Sv (6400 rem) over that period, i.e. an average of 3 Sv per year or 350ย ฮผSv/h. The current annual permitted dose for a radiation worker in the United States is 0.05 Sv (or 5 rem), i.e. an average of 5.7 ฮผSv/h.

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๐Ÿ”— Internet 0

๐Ÿ”— Computing ๐Ÿ”— Computing/Networking

Internet 0 is a low-speed physical layer designed to route 'IP over anything.' It was developed at MIT's Center for Bits and Atoms by Neil Gershenfeld, Raffi Krikorian, and Danny Cohen. When it was invented, a number of other proposals were being labelled as "internet 2." The name was chosen to emphasize that this was designed to be a slow, but very inexpensive internetworking system, and forestall "high-performance" comparison questions such as "how fast is it?"

Effectively, it would enable a platform for pervasive computing -- everything in a building could be on the same network to share data gathering and actuation. A light switch could turn on a light bulb by sending a packet to it, they can be linked together by the user.

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๐Ÿ”— Blinkenlights

๐Ÿ”— Computing ๐Ÿ”— Computing/Computer hardware ๐Ÿ”— Computing/Early computers

In computer jargon, blinkenlights are diagnostic lights on front panels of old mainframe computers. More recently the term applies to status lights of modern network hardware (modems, network hubs, etc.). Blinkenlights disappeared from more recent computers for a number of reasons, the most important being the fact that with faster CPUs a human can no longer interpret the processes in the computer on the fly. Though more sophisticated UI mechanisms have since been developed, blinkenlights may still be present as additional status indicators and familiar skeuomorphs.

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๐Ÿ”— Floydโ€“Hoare logic

๐Ÿ”— Computer science

Hoare logic (also known as Floydโ€“Hoare logic or Hoare rules) is a formal system with a set of logical rules for reasoning rigorously about the correctness of computer programs. It was proposed in 1969 by the British computer scientist and logician Tony Hoare, and subsequently refined by Hoare and other researchers. The original ideas were seeded by the work of Robert W. Floyd, who had published a similar system for flowcharts.

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