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π Wikipedia's ivermectin talk page shows editors' mayhem
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- "Wikipedia's ivermectin talk page shows editors' mayhem" | 2021-09-09 | 36 Upvotes 28 Comments
π Island of Stability
In nuclear physics, the island of stability is a predicted set of isotopes of superheavy elements that may have considerably longer half-lives than known isotopes of these elements. It is predicted to appear as an "island" in the chart of nuclides, separated from known stable and long-lived primordial radionuclides. Its theoretical existence is attributed to stabilizing effects of predicted "magic numbers" of protons and neutrons in the superheavy mass region.
Several predictions have been made regarding the exact location of the island of stability, though it is generally thought to center near copernicium and flerovium isotopes in the vicinity of the predicted closed neutron shell at NΒ =Β 184. These models strongly suggest that the closed shell will confer further stability towards fission and alpha decay. While these effects are expected to be greatest near atomic number ZΒ =Β 114 and NΒ =Β 184, the region of increased stability is expected to encompass several neighboring elements, and there may also be additional islands of stability around heavier nuclei that are doubly magic (having magic numbers of both protons and neutrons). Estimates of the stability of the elements on the island are usually around a half-life of minutes or days; some estimates predict half-lives of millions of years.
Although the nuclear shell model predicting magic numbers has existed since the 1940s, the existence of long-lived superheavy nuclides has not been definitively demonstrated. Like the rest of the superheavy elements, the nuclides on the island of stability have never been found in nature; thus, they must be created artificially in a nuclear reaction to be studied. Scientists have not found a way to carry out such a reaction, for it is likely that new types of reactions will be needed to populate nuclei near the center of the island. Nevertheless, the successful synthesis of superheavy elements up to ZΒ =Β 118 (oganesson) with up to 177 neutrons demonstrates a slight stabilizing effect around elements 110 to 114 that may continue in unknown isotopes, supporting the existence of the island of stability.
π The ADE 651 is a fake bomb detector, sold for up to US$60k each
The ADE 651 is a fake bomb detector produced by the British company Advanced Tactical Security & Communications Ltd (ATSC). Its manufacturer claimed it could detect bombs, guns, ammunition, and more from kilometers away. However, it was a scam, and the device was little more than a dowsing rod. The device was sold for up to US$60,000 each, despite costing almost nothing to produce. It was widely used in the Middle East, and may have led to numerous deadly bombings in Iraq due to its inability to detect explosives. Its inventor, James McCormick, was sentenced to 10 years in prison in 2013 for fraud.
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- "The ADE 651 is a fake bomb detector, sold for up to US$60k each" | 2021-09-08 | 127 Upvotes 85 Comments
π Spaceflight Before 1951
Spaceflight as a practical endeavor began during World War II with the development of operational liquid-fueled rockets. Beginning life as a weapon, the V-2 was pressed into peaceful service after the war at the United States' White Sands Missile Range as well as the Soviet Union's Kapustin Yar. This led to a flourishing of missile designs setting the stage for the exploration of space. The small American WAC Corporal rocket was evolved into the Aerobee, a much more powerful sounding rocket. Exploration of space began in earnest in 1947 with the flight of the first Aerobee, 46 of which had flown by the end of 1950. These and other rockets, both Soviet and American, returned the first direct data on air density, temperature, charged particles and magnetic fields in the Earth's upper atmosphere.
By 1948, the United States Navy had evolved the V-2 design into the Viking capable of more than 100 miles (160Β km) in altitude. The first Viking to accomplish this feat, number four, did so 10 May 1950. The Soviet Union developed a virtual copy of the V-2 called the R-1, which first flew in 1948. Its longer-ranged successor, the R-2, entered military service in 1950. This event marked the entry of both superpowers into the post-V-2 rocketry era.
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- "Spaceflight Before 1951" | 2021-09-06 | 63 Upvotes 31 Comments
π Extracorporeal Membrane Oxygenation
Extracorporeal membrane oxygenation (ECMO), also known as extracorporeal life support (ECLS), is an extracorporeal technique of providing prolonged cardiac and respiratory support to persons whose heart and lungs are unable to provide an adequate amount of gas exchange or perfusion to sustain life. The technology for ECMO is largely derived from cardiopulmonary bypass, which provides shorter-term support with arrested native circulation. The device used is a membrane oxygenator, also known as an artificial lung.
ECMO works by temporarily drawing blood from the body to allow artificial oxygenation of the red blood cells and removal of carbon dioxide. Generally, it is used either post-cardiopulmonary bypass or in late-stage treatment of a person with profound heart and/or lung failure, although it is now seeing use as a treatment for cardiac arrest in certain centers, allowing treatment of the underlying cause of arrest while circulation and oxygenation are supported. ECMO is also used to support patients with the acute viral pneumonia associated with COVID-19 in cases where artificial ventilation alone is not sufficient to sustain blood oxygenation levels.
π Gene Gun
In genetic engineering, a gene gun or biolistic particle delivery system is a device used to deliver exogenous DNA (transgenes), RNA, or protein to cells. By coating particles of a heavy metal with a gene of interest and firing these micro-projectiles into cells using mechanical force, an integration of desired genetic information can be induced into cells. The technique involved with such micro-projectile delivery of DNA is often referred to as biolistics.
This device is able to transform almost any type of cell and is not limited to the transformation of the nucleus; it can also transform organelles, including plastids and mitochondria.
π Lowercase
Lowercase is an extreme form of ambientminimalism where very quiet, usually unheard sounds are amplified to extreme levels. Minimal artist Steve Roden popularized the movement with an album entitled Forms of Paper, in which he made recordings of himself handling paper in various ways. These recordings were commissioned by the Hollywood branch of the Los Angeles Public Library.
π Chekhov's gun
Chekhov's gun (Russian: Π§Π΅Ρ ΠΎΠ²ΡΠΊΠΎΠ΅ ΡΡΠΆΡΡ) is a dramatic principle that states that every element in a story must be necessary, and irrelevant elements should be removed. Elements should not appear to make "false promises" by never coming into play. The statement is recorded in letters by Anton Chekhov several times, with some variation:
- "Remove everything that has no relevance to the story. If you say in the first chapter that there is a rifle hanging on the wall, in the second or third chapter it absolutely must go off. If it's not going to be fired, it shouldn't be hanging there."
- "One must never place a loaded rifle on the stage if it isn't going to go off. It's wrong to make promises you don't mean to keep." Chekhov, letter to Aleksandr Semenovich Lazarev (pseudonym of A. S. Gruzinsky), 1 November 1889. Here the "gun" is a monologue that Chekhov deemed superfluous and unrelated to the rest of the play.
- "If in the first act you have hung a pistol on the wall, then in the following one it should be fired. Otherwise don't put it there." From Gurlyand's Reminiscences of A. P. Chekhov, in Teatr i iskusstvo 1904, No. 28, 11 July, p.Β 521.
Ernest Hemingway mocked the interpretation given by English instructors to the principle. He gives in his essay "The Art of the Short Story" an example of two characters that are introduced and then never again mentioned in his short story "Fifty Grand". Hemingway valued inconsequential details, but conceded that readers will inevitably seek symbolism and significance in these inconsequential details.
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- "Chekhov's Gun" | 2021-09-05 | 257 Upvotes 172 Comments
- "Chekhov's Gun" | 2020-05-14 | 93 Upvotes 72 Comments
- "Chekhov's gun" | 2013-10-13 | 11 Upvotes 8 Comments
π Borax
Borax, also known as sodium borate, sodium tetraborate, or disodium tetraborate, is an important boron compound, a mineral, and a salt of boric acid. Powdered borax is white, consisting of soft colorless crystals that dissolve in water. A number of closely related minerals or chemical compounds that differ in their crystal water content are referred to as borax, and the word is usually used to refer to the octahydrate. Commercially sold borax is partially dehydrated.
Borax is a component of many detergents, cosmetics, and enamel glazes. It is used to make buffer solutions in biochemistry, as a fire retardant, as an anti-fungal compound, in the manufacture of fiberglass, as a flux in metallurgy, neutron-capture shields for radioactive sources, a texturing agent in cooking, as a cross-linking agent in Slime, as an alkali in photographic developers, as a precursor for other boron compounds, and along with its inverse, boric acid, is useful as an insecticide.
In artisanal gold mining, borax is sometimes used as part of a process (as a flux) meant to eliminate the need for toxic mercury in the gold extraction process, although it cannot directly replace mercury. Borax was reportedly used by gold miners in parts of the Philippines in the 1900s.
Borax was first discovered in dry lake beds in Tibet and was imported via the Silk Road to the Arabian Peninsula in the 8th century AD. Borax first came into common use in the late 19th century when Francis Marion Smith's Pacific Coast Borax Company began to market and popularize a large variety of applications under the 20 Mule Team Borax trademark, named for the method by which borax was originally hauled out of the California and Nevada deserts.
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- "Borax" | 2021-09-05 | 81 Upvotes 47 Comments
π Project MKUltra
Project MKUltra (or MK-Ultra), also called the CIA mind control program, is the code name given to a program of experiments on human subjects that were designed and undertaken by the U.S. Central Intelligence Agency, some of which were illegal. Experiments on humans were intended to identify and develop drugs and procedures to be used in interrogations in order to weaken the individual and force confessions through mind control. The project was organized through the Office of Scientific Intelligence of the CIA and coordinated with the United States Army Biological Warfare Laboratories. Code names for drug-related experiments were Project Bluebird and Project Artichoke.
The operation was officially sanctioned in 1953, reduced in scope in 1964 and further curtailed in 1967. It was officially halted in 1973. The program engaged in many illegal activities, including the use of U.S. and Canadian citizens as its unwitting test subjects, which led to controversy regarding its legitimacy. MKUltra used numerous methods to manipulate its subjects' mental states and brain functions. Techniques included the covert administration of high doses of psychoactive drugs (especially LSD) and other chemicals, electroshocks, hypnosis, sensory deprivation, isolation, verbal and sexual abuse, as well as other forms of torture.
The scope of Project MKUltra was broad, with research undertaken at more than 80 institutions, including colleges and universities, hospitals, prisons, and pharmaceutical companies. The CIA operated using front organizations, although sometimes top officials at these institutions were aware of the CIA's involvement.
Project MKUltra was first brought to public attention in 1975 by the Church Committee of the United States Congress and Gerald Ford's United States President's Commission on CIA activities within the United States (also known as the Rockefeller Commission).
Investigative efforts were hampered by CIA Director Richard Helms' order that all MKUltra files be destroyed in 1973; the Church Committee and Rockefeller Commission investigations relied on the sworn testimony of direct participants and on the relatively small number of documents that survived Helms's destruction order. In 1977, a Freedom of Information Act request uncovered a cache of 20,000 documents relating to project MKUltra which led to Senate hearings later that year. Some surviving information regarding MKUltra was declassified in July 2001. In December 2018, declassified documents included a letter to an unidentified doctor discussing work on six dogs made to run, turn and stop via remote control and brain implants.
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- "Project MKUltra" | 2021-09-05 | 29 Upvotes 4 Comments
- "Project MKUltra" | 2019-10-05 | 229 Upvotes 121 Comments