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๐ Yakovlevian Torque
Yakovlevian torque (also known as occipital bending (OB) or counterclockwise brain torque) is the tendency of the right side of the human brain to be warped slightly forward relative to the left and the left side of the human brain to be warped slightly backward relative to the right. This is responsible for certain asymmetries, such as how the lateral sulcus of the human brain is often longer and less curved on the left side of the brain relative to the right. Stated in another way, Yakovlevian Torque can be defined by the existence of right-frontal and left-occipital petalias, which are protrusions of the surface of one hemisphere relative to the other. It is named for Paul Ivan Yakovlev (1894โ1983), a Russian-American neuroanatomist from Harvard Medical School.
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- "Yakovlevian Torque" | 2019-11-08 | 88 Upvotes 34 Comments
๐ Braessโs paradox
Braess' paradox is the observation that adding one or more roads to a road network can slow down overall traffic flow through it. The paradox was postulated in 1968 by German mathematician Dietrich Braess, who noticed that adding a road to a particular congested road traffic network would increase overall journey time.
The paradox may have analogies in electrical power grids and biological systems. It has been suggested that in theory, the improvement of a malfunctioning network could be accomplished by removing certain parts of it. The paradox has been used to explain instances of improved traffic flow when existing major roads are closed.
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- "Braess's Paradox" | 2021-05-16 | 64 Upvotes 30 Comments
- "Braessโs paradox" | 2018-09-22 | 134 Upvotes 37 Comments
- "Braessโ paradox" | 2017-01-08 | 136 Upvotes 91 Comments
- "Braess' paradox: adding a new road to a city can slow down traffic" | 2015-10-16 | 98 Upvotes 61 Comments
๐ Biosphere 2
Biosphere 2 is an American Earth system science research facility located in Oracle, Arizona. Its mission is to serve as a center for research, outreach, teaching, and lifelong learning about Earth, its living systems, and its place in the universe. It is a 3.14-acre (1.27-hectare) structure originally built to be an artificial, materially closed ecological system, or vivarium. It remains the largest closed ecological system ever created.
Constructed between 1987 and 1991, Biosphere 2 was originally meant to demonstrate the viability of closed ecological systems to support and maintain human life in outer space as a substitute for Earth's biosphere. It was designed to explore the web of interactions within life systems in a structure with different areas based on various biological biomes. In addition to the several biomes and living quarters for people, there was an agricultural area and work space to study the interactions between humans, farming, technology and the rest of nature as a new kind of laboratory for the study of the global ecology. Its mission was a two-year closure experiment with a crew of eight humans ("biospherians"). Long-term it was seen as a precursor to gaining knowledge about the use of closed biospheres in space colonization. As an experimental ecological facility it allowed the study and manipulation of a mini biospheric system without harming Earth's biosphere.
Its seven biome areas were a 1,900-square-meter (20,000ย sqย ft) rainforest, an 850-square-meter (9,100ย sqย ft) ocean with a coral reef, a 450-square-meter (4,800ย sqย ft) mangrove wetlands, a 1,300-square-metre (14,000ย sqย ft) savannah grassland, a 1,400-square-meter (15,000ย sqย ft) fog desert, and two anthropogenic biomes: a 2,500-square-meter (27,000ย sqย ft) agricultural system and a human habitat with living spaces, laboratories and workshops. Below ground was an extensive part of the technical infrastructure. Heating and cooling water circulated through independent piping systems and passive solar input through the glass space frame panels covering most of the facility, and electrical power was supplied into Biosphere 2 from an onsite natural gas energy center.
Biosphere 2 was only used twice for its original intended purposes as a closed-system experiment: once from 1991 to 1993, and the second time from March to September 1994. Both attempts ran into problems including low amounts of food and oxygen, die-offs of many animals and plants included in the experiment (though this was anticipated since the project used a strategy of deliberately "species-packing" anticipating losses as the biomes developed), group dynamic tensions among the resident crew, outside politics, and a power struggle over management and direction of the project. Nevertheless, the closure experiments set world records in closed ecological systems, agricultural production, health improvements with the high nutrient and low caloric diet the crew followed, and insights into the self-organization of complex biomic systems and atmospheric dynamics. The second closure experiment achieved total food sufficiency and did not require injection of oxygen.
In June 1994, during the middle of the second experiment, the managing company, Space Biosphere Ventures, was dissolved, and the facility was left in limbo. Columbia University assumed management of the facility in 1995 and used it to run experiments until 2003. It then appeared to be in danger of being demolished to make way for housing and retail stores, but was taken over for research by the University of Arizona in 2007. The University of Arizona took full ownership of the structure in 2011.
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- "Biosphere 2" | 2023-05-26 | 100 Upvotes 50 Comments
๐ The Population Bomb (1968)
The Population Bomb is a 1968 book co-authored by former Stanford University professor Paul R. Ehrlich and former Stanford senior researcher in conservation biology Anne H. Ehrlich. From the opening page, it predicted worldwide famines due to overpopulation, as well as other major societal upheavals, and advocated immediate action to limit population growth. Fears of a "population explosion" existed in the mid-20th century baby boom years, but the book and its authors brought the idea to an even wider audience.
The book has been criticized since its publication for an alarmist tone, and over the subsequent decades, for inaccurate assertions and failed predictions. For instance, regional famines have occurred since the publication of the book, but not world famines. The Ehrlichs themselves still stand by the book despite the flaws identified by its critics, with Paul stating in 2009 that "perhaps the most serious flaw in The Bomb was that it was much too optimistic about the future," despite having predicted catastrophic global famines that never came to pass. They believe that it achieved their goals because "it alerted people to the importance of environmental issues and brought human numbers into the debate on the human future."
๐ 1975 Icelandic Women's Strike
On 24 October 1975, Icelandic women went on strike for the day to "demonstrate the indispensable work of women for Icelandโs economy and society" and to "protest wage discrepancy and unfair employment practices". It was then publicized domestically as Women's Day Off (Kvennafrรญdagurinn). Participants, led by women's organizations, did not go to their paid jobs and did not do any housework or child-rearing for the whole day. Ninety percent of Iceland's female population participated in the strike. Iceland's parliament passed a law guaranteeing equal pay the following year.
๐ FloydโHoare logic
Hoare logic (also known as FloydโHoare 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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- "FloydโHoare logic" | 2015-07-13 | 36 Upvotes 14 Comments
๐ Raven paradox
The raven paradox, also known as Hempel's paradox, Hempel's ravens, or rarely the paradox of indoor ornithology, is a paradox arising from the question of what constitutes evidence for a statement. Observing objects that are neither black nor ravens may formally increase the likelihood that all ravens are black even though, intuitively, these observations are unrelated.
This problem was proposed by the logician Carl Gustav Hempel in the 1940s to illustrate a contradiction between inductive logic and intuition.
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- "Raven paradox" | 2015-04-04 | 69 Upvotes 43 Comments
- "The Raven Paradox (logic)" | 2008-01-13 | 9 Upvotes 16 Comments
๐ Kuleshov effect
The Kuleshov effect is a film editing (montage) effect demonstrated by Soviet filmmaker Lev Kuleshov in the 1910s and 1920s. It is a mental phenomenon by which viewers derive more meaning from the interaction of two sequential shots than from a single shot in isolation.
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- "Kuleshov effect" | 2019-01-02 | 151 Upvotes 31 Comments
๐ Japanese Invasion Money
Japanese invasion money, officially known as Southern Development Bank Notes (Japanese: ๅคงๆฑไบๆฆไบ่ป็ฅจ Dai Tล-A Sensล gunpyล, "Greater East Asia War military scrip"), was currency issued by the Japanese Military Authority, as a replacement for local currency after the conquest of colonies and other states in World War II. In February 1942 in Japan, laws were passed establishing the Wartime Finance Bank and the Southern Development Bank. Both institutions issued bonds to raise funds. The former loaned money primarily to military industries, but also to a wide range of other ventures, including hydroelectric generators, electric power companies, shipbuilding and petroleum. The latter provided financial services in areas occupied by the Japanese military, and Southern Development Bank notes were in fact used as de facto military scrip. In December 1942, the outstanding balance of Southern Development Bank notes stood at more than 470ย million; in March 1945, more than 13ย billion.
Already engaged in war with China, in 1940 the Japanese expanded the scope of their military operations in Asia and finally entered the Second World War in late 1941 with the attack on Pearl Harbor. Japan invaded various Asian countries, occupying vast territories and setting up military administrations.
Beginning with the capture of the Philippines, the Japanese military confiscated all hard currency, both on a federal and individual level, replacing it with locally printed notes bearing a proclamation of military issue. All notes bore the name of the Imperial Japanese government, and some notes proclaimed the "promises to pay the bearer on demand". Called โMickey Mouse Money" by local Filipinos, it was valueless after the overthrow of the Japanese, and tons of it were burned. Japanese troops were ordered to destroy bank records and any remaining currency prior to capitulation.
With the end of World War II, the currency circulated bearing the Japanese name immediately lost any value it once possessed and was discarded en masse. Money that was issued included the Philippines, Burma (now Myanmar), Malaya, North Borneo and Sarawak (now Malaysia), Singapore, Brunei, the Dutch East Indies (now Indonesia) and some areas of Oceania (New Guinea and the Solomon and Gilbert islands). Large amounts of the currency were obtained by Allied forces and civilians at the end of the war; many were kept as wartime souvenirs, and are now in both private and museum collections.
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- "Japanese Invasion Money" | 2021-05-29 | 12 Upvotes 1 Comments
๐ Kyshtym Disaster
The Kyshtym disaster, sometimes referred to as the Mayak disaster or Ozyorsk disaster in newer sources, was a radioactive contamination accident that occurred on 29 September 1957 at Mayak, a plutonium production site for nuclear weapons and nuclear fuel reprocessing plant located in the closed city of Chelyabinsk-40 (now Ozyorsk) in Chelyabinsk Oblast, Russian SFSR, Soviet Union.
The disaster was the second worst nuclear incident (by radioactivity released) after the Chernobyl disaster. It measured as a Level 6 disaster on the International Nuclear Event Scale (INES), making it the third highest on the INES (which ranks by population impact), behind Chernobyl (evacuated 335,000 people) and the Fukushima Daiichi nuclear disaster (evacuated 154,000 people) which are both Level 7 on the INES. At least twenty-two villages were exposed to radiation from the Kyshtym disaster, with a total population of around 10,000 people evacuated. Some were evacuated after a week, but it took almost two years for evacuations to occur at other sites.
The disaster spread hot particles over more than 52,000 square kilometres (20,000ย sqย mi), where at least 270,000 people lived. Since Chelyabinsk-40 (later renamed Chelyabinsk-65 until 1994) was not marked on maps, the disaster was named after Kyshtym, the nearest known town.
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- "Kyshtym Disaster" | 2021-10-13 | 60 Upvotes 37 Comments