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π The American Chestnut Tree
The American chestnut (Castanea dentata) is a large deciduous tree of the beech family native to eastern North America. The American chestnut was one of the most important forest trees throughout its range and was considered the finest chestnut tree in the world.
The species was devastated by chestnut blight, a fungal disease that came from Chinese chestnut trees introduced into North America from East Asia. It is estimated that between 3 and 4 billion American chestnut trees were destroyed in the first half of the 20th century by chestnut blight after the blight's initial discovery in North America in 1904. Very few mature specimens of the tree exist within its historical range, although many small shoots of the former live trees remain. There are hundreds of large (2 to 5Β ft diameter) American chestnuts outside its historical range, some in areas where less virulent strains of the pathogen are more common, such as the 600 to 800 large trees in Northern Michigan. The species is listed as endangered in the United States and Canada. American chestnuts are also susceptible to ink disease, particularly in the southern part of its native range. This susceptibility to ink disease may have contributed to the devastation of the species.
Several groups are attempting to create blight-resistant American chestnuts. Scientists at the SUNY College of Environmental Science and Forestry created the Darling 58 cultivar of American chestnut by inserting the oxalate oxidase gene from wheat into the genome of an American chestnut. When expressed in the cambium of the Darling 58 cultivar, oxalate oxidase detoxifies oxalic acid, resulting in a tree that still gets infected by the blight fungus but that resists girdling of the trunk and survives such infection. As of 2021, the researchers who developed this cultivar are working towards applying for government permission to make these trees available to the public. If approved, these chestnut trees would be the first genetically modified forest trees released into the wild in the United States. Cross-breeding of chestnut species represents an alternate approach to restoring the American chestnut. One approach has been cross-breeding among different partially blight-resistant American chestnuts, with the goal of developing a cultivar with high resistance. Another approach is to crossbreed American chestnuts with Chinese chestnut trees, which are moderately blight-resistant, and then to backcross with American chestnuts, with the goal of creating a cultivar with most of the genetic heritage of American but retaining the blight resistance of the Chinese chestnut.
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- "The American Chestnut Tree" | 2022-02-14 | 118 Upvotes 73 Comments
π Clock on iOS6 iPads is an homage to a 1944 design by Hans Hilfiker
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- "Clock on iOS6 iPads is an homage to a 1944 design by Hans Hilfiker" | 2012-09-20 | 27 Upvotes 20 Comments
π Text from Wikipedia good enough for Oxford University Press to claim as own
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- "Text from Wikipedia good enough for Oxford University Press to claim as own" | 2015-02-28 | 20 Upvotes 1 Comments
π Snottite
Snottite, also snoticle, is a microbial mat of single-celled extremophilic bacteria which hang from the walls and ceilings of caves and are similar to small stalactites, but have the consistency of nasal mucus. In the Frasassi Caves in Italy, over 70% of cells in Snottite have been identified as Acidithiobacillus thiooxidans, with smaller populations including an archaeon in the uncultivated 'G-plasma' clade of Thermoplasmatales (>15%) and a bacterium in the Acidimicrobiaceae family (>5%).
The bacteria derive their energy from chemosynthesis of volcanic sulfur compounds including H2S and warm-water solution dripping down from above, producing sulfuric acid. Because of this, their waste products are highly acidic (approaching pH=0), with similar properties to battery acid. Researchers at the University of Texas have suggested that this sulfuric acid may be a more significant cause of cave formation than the usual explanation offered of the carbonic acid formed from carbon dioxide dissolved in water.
Snottites were brought to attention by researchers Diana Northup and Penny Boston studying them (and other organisms) in a toxic sulfur cave called Cueva de Villa Luz (Cave of the Lighted House), in Tabasco, Mexico. Snottites were first discovered in this cave by Jim Pisarowicz in 1986, who also coined the term.
The BBC series Wonders of the Solar System saw Professor Brian Cox examining snottites and positing that if there is life on Mars, it may be similarly primitive and hidden beneath the surface of the Red Planet.
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- "Snottite" | 2024-04-02 | 57 Upvotes 9 Comments
π Teuvo Kohonen Has Died
Teuvo Kalevi Kohonen (11 July 1934 β 15 December 2021) was a prominent Finnish academic (Dr. Eng.) and researcher. He was professor emeritus of the Academy of Finland.
Prof. Kohonen made many contributions to the field of artificial neural networks, including the Learning Vector Quantization algorithm, fundamental theories of distributed associative memory and optimal associative mappings, the learning subspace method and novel algorithms for symbol processing like redundant hash addressing. He has published several books and over 300 peer-reviewed papers.
Kohonenβs most famous contribution is the Self-Organizing Map (also known as the Kohonen map or Kohonen artificial neural networks, although Kohonen himself prefers SOM). Due to the popularity of the SOM algorithm in many research and in practical applications, Kohonen is often considered to be the most cited Finnish scientist. The current version of the SOM bibliography contains close to 8000 entries.
During most of his career, Prof. Kohonen conducted research at Helsinki University of Technology (TKK). The Neural Networks Research Centre of TKK, a center of excellence appointed by Academy of Finland was founded to conduct research related to Teuvo Kohonen's innovations. After Kohonen's retirement, the center was led by Prof. Erkki Oja and later renamed to Adaptive Informatics Research Centre with widened foci of research.
Teuvo Kohonen was elected the First Vice President of the International Association for Pattern Recognition from 1982 to 1984, and acted as the first president of the European Neural Network Society from 1991 to 1992.
For his scientific achievements, Prof. Kohonen has received a number of prizes including the following:
- IEEE Neural Networks Council Pioneer Award, 1991
- Technical Achievement Award of the IEEE Signal Processing Society, 1995
- IEEE Frank Rosenblatt Award, 2008
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- "Teuvo Kohonen Has Died" | 2021-12-16 | 11 Upvotes 2 Comments
π Policy laundering
Policy laundering is the disguising of the origins of political decisions, laws, or international treaties. The term is based on the similar money laundering.
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- "Policy laundering" | 2018-03-15 | 119 Upvotes 65 Comments
π Solar pond
A solar pond is a pool of saltwater which collects and stores solar thermal energy. The saltwater naturally forms a vertical salinity gradient also known as a "halocline", in which low-salinity water floats on top of high-salinity water. The layers of salt solutions increase in concentration (and therefore density) with depth. Below a certain depth, the solution has a uniformly high salt concentration.
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- "Solar pond" | 2013-09-25 | 78 Upvotes 11 Comments
π Hitler Has Only Got One Ball
"Hitler Has Only Got One Ball", sometimes known as "The River Kwai March", is a World War II British song, the lyrics of which, sung to the tune of the World War I-era "Colonel Bogey March", impugn the masculinity of Nazi leaders by alleging they had missing, deformed, or undersized testicles. Multiple variant lyrics exist, but the most common version refers to rumours that Adolf Hitler had monorchism ("one ball"), and accuses Hermann GΓΆring and Heinrich Himmler of microorchidism ("two but very small") and Joseph Goebbels of anorchia ("no balls at all"). An alternative version suggests Hitler's missing testicle is displayed as a war trophy in the Royal Albert Hall.
The author of the lyrics is unknown, though several claims have been made. The song first appeared among British soldiers in 1939 and was quickly taken up by Allied military and civilians. Its familiarity increased after its use in a scene in the 1957 film The Bridge on the River Kwai. The song has been cited as an example of morally-correct disrespect that used political mockery to boost morale in wartime.
π Functional Fixedness - The Candle Problem
Functional fixedness is a cognitive bias that limits a person to use an object only in the way it is traditionally used. The concept of functional fixedness originated in Gestalt psychology, a movement in psychology that emphasizes holistic processing. Karl Duncker defined functional fixedness as being a "mental block against using an object in a new way that is required to solve a problem". This "block" limits the ability of an individual to use components given to them to complete a task, as they cannot move past the original purpose of those components. For example, if someone needs a paperweight, but they only have a hammer, they may not see how the hammer can be used as a paperweight. Functional fixedness is this inability to see a hammer's use as anything other than for pounding nails; the person couldn't think to use the hammer in a way other than in its conventional function.
When tested, 5-year-old children show no signs of functional fixedness. It has been argued that this is because at age 5, any goal to be achieved with an object is equivalent to any other goal. However, by age 7, children have acquired the tendency to treat the originally intended purpose of an object as special.
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- "Functional Fixedness - The Candle Problem" | 2010-03-22 | 10 Upvotes 5 Comments
π Massachusetts Right to Repair Initiative
The Massachusetts "Right to Repair" Initiative, also known as Question 1, appeared on the Massachusetts 2012 general election ballot as an initiated state statute. The Right to Repair proposal was to require vehicle owners and independent repair facilities in Massachusetts to have access to the same vehicle diagnostic and repair information made available to the manufacturers' Massachusetts dealers and authorized repair facilities. The initiative passed with overwhelming voter support on November 6, 2012, with 86% for and 14% against. The measure, originally filed four times with the Massachusetts Attorney General, was filed by Arthur W. Kinsman, and was assigned initiative numbers 11-17.
2019 Ballot Initiative In early 2019 the Massachusetts Legislature submitted bills advocating change to close loopholes associated with wireless transmission of diagnostic information. Advocates supporting an update to the Massachusetts Right to Repair law have announced that the required signatures have been gathered to place Right to Repair on the November 3, 2020 ballot.
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- "Massachusetts Right to Repair Initiative" | 2016-04-04 | 264 Upvotes 128 Comments