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🔗 Chemicals 🔗 Molecular and Cell Biology 🔗 Evolutionary biology

Evolution of metal ions in biological systems refers to the incorporation of metallic ions into living organisms and how it has changed over time. Metal ions have been associated with biological systems for billions of years, but only in the last century have scientists began to truly appreciate the scale of their influence. Major (iron, manganese, magnesium and zinc) and minor (copper, cobalt, nickel, molybdenum, tungsten) metal ions have become aligned with living organisms through the interplay of biogeochemical weathering and metabolic pathways involving the products of that weathering. The associated complexes have evolved over time.

Natural development of chemicals and elements challenged organisms to adapt or die. Current organisms require redox reactions to induce metabolism and other life processes. Metals have a tendency to lose electrons and are important for redox reactions.

Metals have become so central to cellular function that the collection of metal-binding proteins (referred to as the metallomes) accounts for over 30% of all proteins in the cell. Metals are known to be involved in over 40% of enzymatic reactions, and metal-binding proteins carry out at least one step in almost all biological pathways.

Metals are also toxic so a balance must be acquired to regulate where the metals are in an organism as well as in what quantities. Many organisms have flexible systems in which they can exchange one metal for another if one is scarce. Metals in this discussion are naturally occurring elements that have a tendency to undergo oxidation. Vanadium, molybdenum, cobalt, copper, chromium, iron, manganese, nickel, and zinc are deemed essential because without them biological function is impaired.

🔗 Television 🔗 Telecommunications 🔗 Amateur radio

Slow-scan television (SSTV) is a picture transmission method, used mainly by amateur radio operators, to transmit and receive static pictures via radio in monochrome or color.

A literal term for SSTV is narrowband television. Analog broadcast television requires at least 6 MHz wide channels, because it transmits 25 or 30 picture frames per second (see ITU analog broadcast standards), but SSTV usually only takes up to a maximum of 3 kHz of bandwidth. It is a much slower method of still picture transmission, usually taking from about eight seconds to a couple of minutes, depending on the mode used, to transmit one image frame.

Since SSTV systems operate on voice frequencies, amateurs use it on shortwave (also known as HF by amateur radio operators), VHF and UHF radio.

🔗 Economics 🔗 New York City

The National Debt Clock is a billboard-sized running total display which constantly updates to show the current United States gross national debt and each American family's share of the debt. It is currently installed on the western side of One Bryant Park, west of Sixth Avenue between 42nd and 43rd Streets in Manhattan, New York City. It was the first debt clock installed anywhere.

The idea for the clock came from New York real estate developer Seymour Durst, who wanted to highlight the rising national debt. In 1989, he sponsored the installation of the first clock, which was originally placed on Sixth Avenue between 42nd and 43rd Streets, one block away from Times Square. In 2004, the original clock was dismantled and replaced by a newer clock near 44th Street and Sixth Avenue. In 2008, as the U.S. national debt exceeded $10 trillion for the first time, it was reported that the value of the debt may have exceeded the number of digits in the clock. The lit dollar-sign in the clock's leftmost digit position was later changed to the "1" digit to represent the ten-trillionth place. In 2017, the clock was moved again to One Bryant Park, near its original location.

🔗 Business 🔗 Psychology 🔗 Languages 🔗 Anthroponymy

Nominative determinism is the hypothesis that people tend to gravitate towards areas of work that fit their names. The term was first used in the magazine New Scientist in 1994, after the magazine's humorous Feedback column noted several studies carried out by researchers with remarkably fitting surnames. These included a book on polar explorations by Daniel Snowman and an article on urology by researchers named Splatt and Weedon. These and other examples led to light-hearted speculation that some sort of psychological effect was at work. Since the term appeared, nominative determinism has been an irregularly recurring topic in New Scientist, as readers continue to submit examples. Nominative determinism differs from the related concept aptronym, and its synonyms aptonym, namephreak, and Perfect Fit Last Name, in that it focuses on causality. "Aptronym" merely means the name is fitting, without saying anything about why it has come to fit.

The idea that people are drawn to professions that fit their name was suggested by psychologist Carl Jung, citing as an example Sigmund Freud who studied pleasure and whose surname means "joy". A few recent empirical studies have indicated that certain professions are disproportionately represented by people with appropriate surnames (and sometimes given names), though the methods of these studies have been challenged. One explanation for nominative determinism is implicit egotism, which states that humans have an unconscious preference for things they associate with themselves. An alternative explanation is genetic: a person might be named Smith or Taylor because that was originally their occupation, and they would pass on their genes to their descendants, including an aptitude for activities involving strength in the case of Smith, or dexterity in the case of Taylor.

🔗 Mathematics

A mathematical coincidence is said to occur when two expressions with no direct relationship show a near-equality which has no apparent theoretical explanation.

For example, there is a near-equality close to the round number 1000 between powers of 2 and powers of 10:

${\displaystyle 2^{10}=1024\approx 1000=10^{3}.}$

Some mathematical coincidences are used in engineering when one expression is taken as an approximation of another.

🔗 Soviet Union 🔗 Firearms

The TP-82 (Russian: ТП-82) was a triple-barrelled Soviet pistol that was carried by cosmonauts on space missions.

It was intended as a survival aid to be used after landings and before recovery in the Siberian wilderness. The TP-82 was the result of cosmonaut Alexei Leonov's concerns after being stranded in the Siberian wilderness when his Voskhod capsule malfunctioned. He feared that the 9mm pistol that was provided in the survival kit would be ineffective against the Siberian wildlife, namely bears and wolves.

The upper two shotgun barrels used 12.5×70 mm ammunition (40 gauge), and the lower rifled barrel used 5.45×39mm ammunition developed for the AK-74 assault rifle. The TP-82 has a large lever on the left side of the receiver that opens the action and a small grip-safety under the trigger-guard that resembles a secondary trigger.

The pistol could be used for hunting, to defend against predators and for visible and audible distress signals. The detachable buttstock was also a machete that came with a canvas sheath. TP-82s were carried regularly on Soviet and Russian space missions from 1986 to 2007. They were part of the Soyuz Portable Emergency-Survival Kit (Носимый аварийный запас, Nosimyi Avariynyi Zapas, NAZ). In 2007, the media reported that the remaining ammunition for the TP-82 had become unusable and that a regular semi-automatic pistol would be used on future missions.

🔗 United States 🔗 Computing 🔗 Computing/Computer hardware 🔗 Plan 9

The AT&T Hobbit is a microprocessor design that AT&T Corporation developed in the early 1990s. It was based on the company's CRISP (C-language Reduced Instruction Set Processor) design, which in turn grew out of Bell Labs' C Machine design of the late 1980s. C Machine, CRISP and Hobbit were optimized for running the C programming language. The design concentrated on fast instruction decoding, indexed array access and procedure calls. Its processor was partially RISC-like. The project ended in 1994 because the Hobbit failed to achieve commercially viable sales.

🔗 United States 🔗 United States/North Carolina 🔗 Aviation 🔗 Military history 🔗 Disaster management 🔗 Military history/Military aviation 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 United States/Military history - U.S. military history 🔗 Aviation/Aviation accident 🔗 Military history/Military science, technology, and theory 🔗 Military history/Weaponry

The 1961 Goldsboro B-52 crash was an accident that occurred near Goldsboro, North Carolina, on 23 January 1961. A Boeing B-52 Stratofortress carrying two 3–4-megaton Mark 39 nuclear bombs broke up in mid-air, dropping its nuclear payload in the process. The pilot in command, Walter Scott Tulloch, ordered the crew to eject at 9,000 feet (2,700 m). Five crewmen successfully ejected or bailed out of the aircraft and landed safely, another ejected, but did not survive the landing, and two died in the crash. Information declassified in 2013 showed that one of the bombs came very close to detonating.

🔗 Graphic design

Corporate Memphis is a term used (often disparagingly) to describe a flat, geometric art style, widely used in Big Tech illustrations in the late 2010s and early 2020s. It is often criticized as seeming uninspired and dystopian.

🔗 Computing 🔗 Computing/Computer hardware

Rekursiv was a computer processor designed by David M. Harland in the mid-1980s for Linn Smart Computing in Glasgow, Scotland. It was one of the few computer architectures intended to implement object-oriented concepts directly in hardware, a form of high-level language computer architecture. The Rekursiv operated directly on objects rather than bits, nibbles, bytes and words. Virtual memory was used as a persistent object store and unusually, the processor instruction set supported recursion (hence the name).

The project originated in an initiative within the hi-fi manufacturer Linn Products to improve its manufacturing automation systems, which at the time ran on a DEC VAX minicomputer. This resulted in the design of Lingo, an object-oriented programming language derived from Smalltalk and ALGOL. Due to the poor performance of Lingo on the VAX, a subsidiary company, Linn Smart Computing Ltd., was formed to develop a new processor to efficiently run Lingo.

The Rekursiv processor consisted of four gate-array chips named Numerik (32-bit ALU), Logik (instruction sequencer), Objekt (object-oriented memory management unit) and Klock (processor clock and support logic). A small number of prototype VMEbus boards, called Hades, comprising these four chips plus 80 MB of RAM were produced. These were intended for installation in a host system such as a Sun-3 workstation.

Although the Rekursiv was never fully developed and was not a commercial success, several Hades boards were used in academic research projects in the UK. The last known copy of a Rekursiv computer ended up at the bottom of the Forth and Clyde canal in Glasgow.