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Biography
Clyde Cowan
Clyde Lorrain Cowan Jr (December 6, 1919 in Detroit, Michigan – May 24, 1974 in Bethesda, Maryland) was an American physicist, the co-discoverer of the neutrino along with Frederick Reines. The discovery was made in 1956 in the neutrino experiment.[1] Frederick Reines received the Nobel Prize in Physics in 1995 in both their names. Born the oldest of four children in Detroit, Michigan, Cowa
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  • 15 Nov 2022
Topic Review
High-Resolution Transmission Electron Microscopy
High-resolution transmission electron microscopy is an imaging mode of specialized transmission electron microscopes that allows for direct imaging of the atomic structure of samples. It is a powerful tool to study properties of materials on the atomic scale, such as semiconductors, metals, nanoparticles and sp2-bonded carbon (e.g., graphene, C nanotubes). While this term is often also used to refer to high resolution scanning transmission electron microscopy, mostly in high angle annular dark field mode, this article describes mainly the imaging of an object by recording the two-dimensional spatial wave amplitude distribution in the image plane, in analogy to a "classic" light microscope. For disambiguation, the technique is also often referred to as phase contrast transmission electron microscopy. At present, the highest point resolution realised in phase contrast transmission electron microscopy is around 0.5 ångströms (0.050 nm). At these small scales, individual atoms of a crystal and its defects can be resolved. For 3-dimensional crystals, it may be necessary to combine several views, taken from different angles, into a 3D map. This technique is called electron crystallography. One of the difficulties with high resolution transmission electron microscopy is that image formation relies on phase contrast. In phase-contrast imaging, contrast is not intuitively interpretable, as the image is influenced by aberrations of the imaging lenses in the microscope. The largest contributions for uncorrected instruments typically come from defocus and astigmatism. The latter can be estimated from the so-called Thon ring pattern appearing in the Fourier transform modulus of an image of a thin amorphous film.
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  • 15 Nov 2022
Topic Review
Forth and Bargy Dialect
The Forth and Bargy dialect, also known as Yola, is an extinct Anglic language once spoken in the baronies of Forth and Bargy in County Wexford, Ireland. It is thought to have evolved from Middle English, which was brought to Ireland during the Norman invasion, beginning in 1169. As such, it was similar to the Fingallian dialect of the Fingal area. Both became extinct in the 19th century, when they were replaced by modern Hiberno-English. The name "Yola" means "old" in the dialect.
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  • 21 Nov 2022
Biography
Pierre-Joseph Proudhon
Pierre-Joseph Proudhon (/ˈpruːdɒn/;[1] French: [pjɛʁʒozɛf pʁudɔ̃]; 15 January 1809 – 19 January 1865) was a French politician, philosopher and the founder of mutualist philosophy. He was the first person to declare himself an anarchist,[2][3] using that term, and is widely regarded as one of the ideology's most influential theorists. Proudhon is even considered by many to be the "fa
  • 7.0K
  • 15 Nov 2022
Topic Review
Allosaurus
Allosaurus (/ˌæləˈsɔːrəs/) is a genus of large carnosaurian theropod dinosaur that lived 155 to 145 million years ago during the Late Jurassic epoch (Kimmeridgian to late Tithonian). The name "Allosaurus" means "different lizard" alluding to its unique (at the time of its discovery) concave vertebrae. It is derived from the Greek ἄλλος (allos) ("different, other") and σαῦρος (sauros) ("lizard / generic reptile"). The first fossil remains that could definitively be ascribed to this genus were described in 1877 by paleontologist Othniel Charles Marsh. As one of the first well-known theropod dinosaurs, it has long attracted attention outside of paleontological circles. Allosaurus was a large bipedal predator. Its skull was light, robust and equipped with dozens of sharp, serrated teeth. It averaged 8.5 meters (28 ft) in length for A. fragilis, with the largest specimens estimated as being 9.7 metres (32 ft) long. Relative to the large and powerful hindlimbs, its three-fingered forelimbs were small, and the body was balanced by a long and heavily muscled tail. It is classified as an allosaurid, a type of carnosaurian theropod dinosaur. The genus has a complicated taxonomy, and includes at least three valid species, the best known of which is A. fragilis. The bulk of Allosaurus remains have come from North America's Morrison Formation, with material also known from Portugal. It was known for over half of the 20th century as Antrodemus, but a study of the abundant remains from the Cleveland-Lloyd Dinosaur Quarry brought the name "Allosaurus" back to prominence and established it as one of the best-known dinosaurs. As the most abundant large predator in the Morrison Formation, Allosaurus was at the top of the food chain, probably preying on contemporaneous large herbivorous dinosaurs, and perhaps other predators. Potential prey included ornithopods, stegosaurids, and sauropods. Some paleontologists interpret Allosaurus as having had cooperative social behavior, and hunting in packs, while others believe individuals may have been aggressive toward each other, and that congregations of this genus are the result of lone individuals feeding on the same carcasses.
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  • 16 Nov 2022
Topic Review
Carbonaceous Biochemical Oxygen Demand
Carbonaceous biochemical oxygen demand or CBOD is a method defined test measured by the depletion of dissolved oxygen by biological organisms in a body of water in which the contribution from nitrogenous bacteria has been suppressed. CBOD is a method defined parameter is widely used as an indication of the pollutant removal from wastewater. It is listed as a conventional pollutant in the U.S. Clean Water Act.
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  • 21 Nov 2022
Topic Review
Synesthesia
Synesthesia (American English) or synaesthesia (British English) is a perceptual phenomenon in which stimulation of one sensory or cognitive pathway leads to involuntary experiences in a second sensory or cognitive pathway. People who report a lifelong history of such experiences are known as synesthetes. Awareness of synesthetic perceptions varies from person to person. In one common form of synesthesia, known as grapheme–color synesthesia or color–graphemic synesthesia, letters or numbers are perceived as inherently colored. In spatial-sequence, or number form synesthesia, numbers, months of the year, or days of the week elicit precise locations in space (e.g., 1980 may be "farther away" than 1990), or may appear as a three-dimensional map (clockwise or counterclockwise). Synesthetic associations can occur in any combination and any number of senses or cognitive pathways. Little is known about how synesthesia develops. It has been suggested that synesthesia develops during childhood when children are intensively engaged with abstract concepts for the first time. This hypothesis – referred to as semantic vacuum hypothesis – could explain why the most common forms of synesthesia are grapheme–color, spatial sequence, and number form. These are usually the first abstract concepts that educational systems require children to learn. Difficulties have been recognized in adequately defining synesthesia. Many different phenomena have been included in the term synesthesia, and in many cases the terminology seems to be inaccurate. A more accurate but less common term may be ideasthesia. The earliest recorded case of synesthesia is attributed to the Oxford University academic and philosopher John Locke, who, in 1690, made a report about a blind man who said he experienced the color scarlet when he heard the sound of a trumpet. However, there is disagreement as to whether Locke described an actual instance of synesthesia or was using a metaphor. The first medical account came from German physician Georg Tobias Ludwig Sachs in 1812. The term is from the Ancient Greek σύν syn, 'together', and αἴσθησις aisthēsis, 'sensation'.
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  • 15 Nov 2022
Topic Review
Mercury's Magnetic Field
Mercury's magnetic field is approximately a magnetic dipole (meaning the field has only two magnetic poles) apparently global, on planet Mercury. Data from Mariner 10 led to its discovery in 1974; the spacecraft measured the field's strength as 1.1% that of Earth's magnetic field. The origin of the magnetic field can be explained by dynamo theory. The magnetic field is strong enough near the bow shock to slow the solar wind, which induces a magnetosphere.
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  • 15 Nov 2022
Topic Review
Medicine Lodge Treaty
The Medicine Lodge Treaty is the overall name for three treaties signed near Medicine Lodge, Kansas, between the Federal government of the United States and southern Plains Indian tribes in October 1867, intended to bring peace to the area by relocating the Native Americans to reservations in Indian Territory and away from European-American settlement. The treaty was negotiated after investigation by the Indian Peace Commission, which in its final report in 1868 concluded that the wars had been preventable. They determined that the United States government and its representatives, including the United States Congress, had contributed to the warfare on the Great Plains by failing to fulfill their legal obligations and to treat the Native Americans with honesty. The U.S. government and tribal chiefs met at a place traditional for Native American ceremonies, at their request. The first treaty was signed October 21, 1867, with the Kiowa and Comanche tribes. The second, with the Kiowa-Apache, was signed the same day. The third treaty was signed with the Southern Cheyenne and Arapaho on October 28. Under the Medicine Lodge Treaty, the tribes were assigned reservations of diminished size compared to territories defined in an 1865 treaty. The treaty tribes never ratified the treaty by vote of adult males, as it required. In addition, by changing allotment policy under the Dawes Act and authorizing sales under the Agreement with the Cheyenne and Arapaho (1890) and the Agreement with the Comanche, Kiowa and Apache (1892) signed with the Cherokee Commission, the Congress effectively further reduced their reservation territory. The Kiowa chief Lone Wolf filed suit against the government for fraud on behalf of the tribes in Lone Wolf v. Hitchcock. In 1903 the U.S. Supreme Court ruled against the tribes, determining that the Congress had "plenary power" and the political right to make such decisions. In the aftermath of that case, Congress acted unilaterally on land decisions related to other reservations as well. Because of the outstanding issues with the treaty and subsequent government actions, in the mid-20th century, the Kiowa, Arapaho and Comanche filed several suits for claims against the U.S. government. Over decades, they won substantial settlements of monetary compensation in the amount of tens of millions of dollars, although it took years for the cases to be resolved.
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  • 15 Nov 2022
Biography
Valery Rubakov
Valery Anatolyevich Rubakov (Russian: Валерий Анатольевич Рубаков, born 16 February 1955 in Moscow, USSR) is a Russian theoretical physicist. His scientific interests include quantum field theory, elementary particle physics, and cosmology. He is affiliated with the Institute for Nuclear Research (INR) of the Russian Academy of Sciences in Moscow. Rubakov studied phys
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  • 15 Nov 2022
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