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Catastrophe
Catastrophe or catastrophic comes from the Greek κατά (''kata'') = down; στροφή (''strophē'') = turning ( el, καταστροφή). It may refer to: A general or specific event * Disaster, a devastating event * The Asia Minor Catastrophe, a Greek name for the 1923 Greek defeat at the Greco-Turkish War (1919–1922) and the population exchange between Greece and Turkey after the defeat * The Holocaust, also known by the Hebrew name ''HaShoah'' which translates to "The Catastrophe" * The Chernobyl Catastrophe, a name of the 1986 Chernobyl disaster * Blue sky catastrophe, a type of bifurcation of a periodic orbit, where the orbit ''vanishes into the blue sky'' * Catastrophic failure, complete failure of a system from which recovery is impossible (e.g. a bridge collapses) * Climatic catastrophe, forced transition of climate system to a new climate state at a rate which is more rapid than the rate of change of the external forcing * Cosmic catastrophe, thought experiment ab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitotic Catastrophe
Mitotic Catastrophe has been defined as either a cellular mechanism to prevent potentially cancerous cells from proliferating or as a mode of cellular death that occurs following improper cell cycle progression or entrance. Mitotic catastrophe can be induced by prolonged activation of the spindle assembly checkpoint, errors in mitosis, or DNA damage and functioned to prevent genomic instability. It is a mechanism that is being researched as a potential therapeutic target in cancers, and numerous approved therapeutics induce mitotic catastrophe. Term usage Multiple attempts to specifically define mitotic catastrophe have been made since the term was first used to describe a temperature dependent lethality in the yeast, ''Schizosaccharomyces pombe,'' that demonstrated abnormal segregation of chromosomes. The term has been used to define a mechanism of cellular death that occurs while a cell is in mitosis or as a method of oncosuppression that prevents potentially tumorigenic cells ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catastrophe (drama)
In drama, particularly the tragedies of classical antiquity, the catastrophe is the final resolution in a poem or narrative plot, which unravels the intrigue and brings the piece to a close. In comedies, this may be a marriage between main characters; in tragedies, it may be the death of one or more main characters. It is the final part of a play, following the protasis, epitasis, and catastasis. The catastrophe is either simple or complex, for which also the fable and action are denominated. In a simple catastrophe, there is no change in the state of the main characters, nor any discovery or unravelling; the plot being only a mere passage out of agitation, to quiet and repose. This catastrophe is rather accommodated to the nature of the epic poem, than of the tragedy. In a complex catastrophe, the main character undergoes a change of fortune, sometimes by means of a discovery, and sometimes without. The qualifications of this change are that it be probable and necessary: in orde ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Malthusian Catastrophe
Malthusianism is the idea that population growth is potentially exponential while the growth of the food supply or other resources is linear, which eventually reduces living standards to the point of triggering a population die off. This event, called a Malthusian catastrophe (also known as a Malthusian trap, population trap, Malthusian check, Malthusian crisis, Malthusian spectre, or Malthusian crunch) occurs when population growth outpaces agricultural production, causing famine or war, resulting in poverty and depopulation. Such a catastrophe inevitably has the effect of forcing the population to "correct" back to a lower, more easily sustainable level (quite rapidly, due to the potential severity and unpredictable results of the mitigating factors involved, as compared to the relatively slow time scales and well-understood processes governing unchecked growth or growth affected by preventive checks). Malthusianism has been linked to a variety of political and social movemen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chernobyl Disaster
The Chernobyl disaster was a nuclear accident that occurred on 26 April 1986 at the No. 4 nuclear reactor, reactor in the Chernobyl Nuclear Power Plant, near the city of Pripyat in the north of the Ukrainian Soviet Socialist Republic, Ukrainian SSR in the Soviet Union. It is one of only two nuclear energy accidents rated at seven—the maximum severity—on the International Nuclear Event Scale, the other being the 2011 Fukushima nuclear disaster in Japan. The initial emergency response, together with later decontamination of the environment, involved more than Chernobyl liquidators, 500,000 personnel and cost an estimated 18 billion Soviet rouble, roubles—roughly US$68 billion in 2019, adjusted for inflation. The accident occurred during a safety test meant to measure the ability of the steam turbine to power the emergency feedwater pumps of an RBMK, RBMK-type nuclear reactor in the event of a simultaneous loss of external power and major coolant leak. During a pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catastrophe (film)
''Catastrophe'' is a 1977 American documentary film that is written and directed by Larry Savadove and narrated by actor William Conrad about natural and man-made disasters. Disasters featured * The footage of the Hindenburg disaster in 1937. * The tornado that hit Xenia, Ohio in 1974 * Hurricane Camille in 1969. * The Dust Bowl during the Great Depression * The 1974 Joelma fire in Brazil. * The eruption of Mount Etna in Italy in 1971. * The sinking of the SS Andrea Doria in 1956. * The accidents during the 1973 Indianapolis 500. Release Theatrical ''Catastrophe'' premiered in Tucson, Arizona on April 20, 1977 and later received a wide release in the United States in February 1978. Home media In 1987, Embassy Home Entertainment (later renamed as Nelson Entertainment) released the film on VHS. Television broadcasts The film premiered on premium cable network Home Box Office (HBO) in March 1979. The film aired on the superstation feed of Chicago independent station An inde ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultraviolet Catastrophe
The ultraviolet catastrophe, also called the Rayleigh–Jeans catastrophe, was the prediction of late 19th century/early 20th century classical physics that an ideal black body at thermal equilibrium would emit an infinity, unbounded quantity of energy as wavelength decreased into the ultraviolet range. The term "ultraviolet catastrophe" was first used in 1911 by Paul Ehrenfest, but the concept originated with the 1900 statistical derivation of the Rayleigh–Jeans law. The phrase refers to the fact that the Rayleigh–Jeans law accurately predicts experimental results at radiative frequencies below 100 Terahertz (unit), THz, but begins to diverge from empirical observations as these frequencies reach the ultraviolet region of the electromagnetic spectrum. Since the first use of this term, it has also been used for other predictions of a similar nature, as in quantum electrodynamics and such cases as ultraviolet divergence. Problem The Rayleigh-Jeans law is an approximati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blue Sky Catastrophe
The blue sky catastrophe is a form of orbital indeterminacy, and an element of bifurcation theory. Orbital dynamics Blue sky catastrophe is a type of bifurcation of a periodic orbit. In other words, it describes a sort of behaviour stable solutions of a set of differential equations can undergo as the equations are gradually changed. This type of bifurcation is characterised by both the period and length of the orbit approaching infinity as the control parameter approaches a finite bifurcation value, but with the orbit still remaining within a bounded part of the phase space, and without loss of stability before the bifurcation point. In other words, the orbit ''vanishes into the blue sky''. Applications of blue sky catastrophe in other fields The bifurcation has found application in, amongst other places, slow-fast models of computational neuroscience. The possibility of the phenomenon was raised by David Ruelle and Floris Takens in 1971, and explored by R.L. Devaney and othe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Error Catastrophe
Error catastrophe refers to the cumulative loss of genetic information in a lineage of organisms due to high mutation rates. The mutation rate above which error catastrophe occurs is called the error threshold. Both terms were coined by Manfred Eigen in his mathematical evolutionary theory of the quasispecies. The term is most widely used to refer to mutation accumulation to the point of inviability of the organism or virus, where it cannot produce enough viable offspring to maintain a population. This use of Eigen's term was adopted by Lawrence Loeb and colleagues to describe the strategy of lethal mutagenesis to cure HIV by using mutagenic ribonucleoside analogs. There was an earlier use of the term introduced in 1963 by Leslie Orgel in a theory for cellular aging, in which errors in the translation of proteins involved in protein translation would amplify the errors until the cell was inviable. This theory has not received empirical support. Error catastrophe is predicted ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Bronze Age Collapse
The Late Bronze Age collapse was a time of widespread societal collapse during the 12th century BC, between c. 1200 and 1150. The collapse affected a large area of the Eastern Mediterranean ( North Africa and Southeast Europe) and the Near East, in particular Egypt, eastern Libya, the Balkans, the Aegean, Anatolia, and the Caucasus. It was sudden, violent, and culturally disruptive for many Bronze Age civilizations, and it brought a sharp economic decline to regional powers, notably ushering in the Greek Dark Ages. The palace economy of Mycenaean Greece, the Aegean region, and Anatolia that characterized the Late Bronze Age disintegrated, transforming into the small isolated village cultures of the Greek Dark Ages, which lasted from around 1100 to the beginning of the better-known Archaic age around 750 BC. The Hittite Empire of Anatolia and the Levant collapsed, while states such as the Middle Assyrian Empire in Mesopotamia and the New Kingdom of Egypt survived but w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cosmological Constant Problem
In cosmology, the cosmological constant problem or vacuum catastrophe is the disagreement between the observed values of vacuum energy density (the small value of the cosmological constant) and theoretical large value of zero-point energy suggested by quantum field theory. Depending on the Planck energy cutoff and other factors, the quantum vacuum energy contribution to the effective cosmological constant is calculated to be as little as 50 and as much as 120 orders of magnitude greater than observed, a state of affairs described by physicists as "the largest discrepancy between theory and experiment in all of science" and "the worst theoretical prediction in the history of physics". History The basic problem of a vacuum energy producing a gravitational effect was identified as early as 1916 by Walther Nernst. He predicted that the value had to be either zero or very small. In 1926, W. Lenz concluded that "If one allows waves of the shortest observed wavelengths λ ≈ 2 � ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nedelin Catastrophe
The Nedelin catastrophe or Nedelin disaster was a launch pad accident that occurred on 24 October 1960 at Baikonur test range (of which Baikonur Cosmodrome is a part), during the development of the Soviet R-16 ICBM. As a prototype of the missile was being prepared for a test flight, an explosion occurred when the second stage engine ignited accidentally, killing an unknown number of military and technical personnel working on the preparations. Despite the magnitude of the disaster, news of it was suppressed for many years and the Soviet government did not acknowledge the event until 1989. The disaster is named after Chief marshal of Artillery Mitrofan Ivanovich Nedelin, who was killed in the explosion. As commanding officer of the Soviet Union's Strategic Rocket Forces, Nedelin was the head of the R-16 development program. Launch preparations On 23 October 1960, the prototype R-16 had been installed on launching pad 41 (''russian: стартовая позиция 41'') aw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron Catastrophe
The iron catastrophe was a postulated major geological event early in the history of Earth, where heavy metals such as iron and nickel congregated in the core during a geologically brief period. The original accretion of the Earth's material into a spherical mass is thought to have resulted in a relatively uniform composition. While residual heat from the collision of the material that formed the Earth was significant, heating from radioactive materials in this mass gradually increased the temperature until a critical condition was reached. As material became molten enough to allow movement, the denser iron and nickel, evenly distributed throughout the mass, began to migrate to the center of the planet to form the core. The gravitational potential energy released by the sinking of the dense NiFe globules, along with any cooler, denser solid material, is thought to have been a runaway process, increasing the temperature of the protoplanet above the melting point of most components, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
