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Metriorhynchids were the only group of archosaurs to become fully adapted to the marine realm, becoming pelagic in lifestyle. With tail flukes, reduced limb musculature, and long bones histologically comparable to other obligately aquatic animals, they were almost certainly incapable of terrestrial locomotion; combined... | Metriorhynchidae | Wikipedia | 466 | 5353692 | https://en.wikipedia.org/wiki/Metriorhynchidae | Biology and health sciences | Other prehistoric archosaurs | Animals |
The classification presented by Young and Andrade in 2009 was approved in later studies of the Metriorhynchidae. Metriorhynchidae is a node-based taxon defined in the PhyloCode by Mark T. Young and colleagues in 2024 as "the smallest clade within Metriorhynchoidea containing Thalattosuchus superciliosus, Gracilineustes... | Metriorhynchidae | Wikipedia | 288 | 5353692 | https://en.wikipedia.org/wiki/Metriorhynchidae | Biology and health sciences | Other prehistoric archosaurs | Animals |
A personal flotation device (PFD; also referred to as a life jacket, life preserver, life belt, Mae West, life vest, life saver, cork jacket, buoyancy aid or flotation suit) is a flotation device in the form of a vest or suit that is worn by a user to prevent the wearer from drowning in a body of water. The device will... | Personal flotation device | Wikipedia | 452 | 1481498 | https://en.wikipedia.org/wiki/Personal%20flotation%20device | Technology | Basics_7 | null |
In a letter to the Naval Chronicle, dated February 1802, Abraham Bosquet proposed issuing Royal Navy Ships with "strong canvas bags of dimensions, when filled with cork shavings, equal to about that of a bed bolster, coiled in manner like a collar, and sufficiently wide for the head and shoulders to pass through."
In ... | Personal flotation device | Wikipedia | 470 | 1481498 | https://en.wikipedia.org/wiki/Personal%20flotation%20device | Technology | Basics_7 | null |
In 1904 the rigid cork material was supplanted by pouches containing watertight cells filled with kapok, a vegetable material. These soft cells were much more flexible and comfortable to wear compared with devices using hard cork pieces. Kapok buoyancy was used in many navies fighting in World War II.
In 1972 yellow o... | Personal flotation device | Wikipedia | 462 | 1481498 | https://en.wikipedia.org/wiki/Personal%20flotation%20device | Technology | Basics_7 | null |
The Mae West was a common nickname for the first inflatable life preserver, which was invented in 1928 by Peter Markus (1885–1974) (US Patent 1694714), with his subsequent improvements in 1930 and 1931. The nickname originated because someone wearing the inflated life preserver often appeared to be as large-breasted as... | Personal flotation device | Wikipedia | 434 | 1481498 | https://en.wikipedia.org/wiki/Personal%20flotation%20device | Technology | Basics_7 | null |
Life jackets or life vests are mandatory on airplanes flying over water bodies, in which case they consist of a pair of air cells (bladders) that can be inflated by triggering the release of carbon dioxide gas from a canister—one for each cell. Alternately, the cells can be inflated "orally", that is by blowing into a ... | Personal flotation device | Wikipedia | 394 | 1481498 | https://en.wikipedia.org/wiki/Personal%20flotation%20device | Technology | Basics_7 | null |
Some buoyancy aids also come designed especially for children and youth. These vests may include one or two understraps to be worn between the legs of the wearer and also a headrest flap. The understraps are designed to keep the vest from riding up when worn in the water and restrict the wearer from slipping out of the... | Personal flotation device | Wikipedia | 437 | 1481498 | https://en.wikipedia.org/wiki/Personal%20flotation%20device | Technology | Basics_7 | null |
Quality life jackets always provide more buoyancy than offered by the buoyancy aids alone. The positioning of the buoyancy on the wearer's torso is such that a righting moment (rotational force) results that will eventually turn most persons who are floating face down in the water (for example, because they are unconsc... | Personal flotation device | Wikipedia | 474 | 1481498 | https://en.wikipedia.org/wiki/Personal%20flotation%20device | Technology | Basics_7 | null |
To be on the safe side, a pill-activated inflation device is preferred. A small pill that dissolves on water contact is the safest option, as it also works in shallow waters where a hydrostatic activator fails. This type of jacket is called an 'automatic'. As it is more sensitive to the presence of water, early models ... | Personal flotation device | Wikipedia | 490 | 1481498 | https://en.wikipedia.org/wiki/Personal%20flotation%20device | Technology | Basics_7 | null |
Because it is a full-body suit, the Mark 10 provides thermal protection once the wearer reaches the surface, and the Royal Navy has successfully tested it at depths.
Buoyancy compensator
Scuba divers commonly wear a buoyancy compensator, which has an inflatable gas chamber. The amount of gas can be increased or dec... | Personal flotation device | Wikipedia | 499 | 1481498 | https://en.wikipedia.org/wiki/Personal%20flotation%20device | Technology | Basics_7 | null |
Anomura (sometimes Anomala) is a group of decapod crustaceans, including hermit crabs and others. Although the names of many anomurans include the word crab, all true crabs are in the sister group to the Anomura, the Brachyura (the two groups together form the clade Meiura).
Description
The name Anomura derives from a... | Anomura | Wikipedia | 468 | 1481660 | https://en.wikipedia.org/wiki/Anomura | Biology and health sciences | Crabs and hermit crabs | Animals |
Some of the internal relationships within Anomura are shown in the cladogram below, which shows Hippidae as sister to Paguroidea, and resolves Parapaguridae outside of Paguroidea:
Classification
The infraorder Anomura contained seven extant superfamilies:
The oldest fossil attributed to Anomura is Platykotta, from th... | Anomura | Wikipedia | 96 | 1481660 | https://en.wikipedia.org/wiki/Anomura | Biology and health sciences | Crabs and hermit crabs | Animals |
Copper(II) chloride, also known as cupric chloride, is an inorganic compound with the chemical formula . The monoclinic yellowish-brown anhydrous form slowly absorbs moisture to form the orthorhombic blue-green dihydrate , with two water molecules of hydration. It is industrially produced for use as a co-catalyst in th... | Copper(II) chloride | Wikipedia | 472 | 1481873 | https://en.wikipedia.org/wiki/Copper%28II%29%20chloride | Physical sciences | Halide salts | Chemistry |
The reported melting point of copper(II) chloride of is a melt of a mixture of copper(I) chloride and copper(II) chloride. The true melting point of can be extrapolated by using the melting points of the mixtures of CuCl and . Copper(II) chloride reacts with several metals to produce copper metal or copper(I) chlorid... | Copper(II) chloride | Wikipedia | 473 | 1481873 | https://en.wikipedia.org/wiki/Copper%28II%29%20chloride | Physical sciences | Halide salts | Chemistry |
Once prepared, a solution of may be purified by crystallization. A standard method takes the solution mixed in hot dilute hydrochloric acid, and causes the crystals to form by cooling in a calcium chloride () ice bath.
There are indirect and rarely used means of using copper ions in solution to form copper(II) chlori... | Copper(II) chloride | Wikipedia | 450 | 1481873 | https://en.wikipedia.org/wiki/Copper%28II%29%20chloride | Physical sciences | Halide salts | Chemistry |
Copper(II) chloride dihydrate promotes the hydrolysis of acetonides, i.e., for deprotection to regenerate diols or aminoalcohols, as in this example (where TBDPS = tert-butyldiphenylsilyl):
also catalyses the free radical addition of sulfonyl chlorides to alkenes; the alpha-chlorosulfone may then undergo elimination ... | Copper(II) chloride | Wikipedia | 440 | 1481873 | https://en.wikipedia.org/wiki/Copper%28II%29%20chloride | Physical sciences | Halide salts | Chemistry |
Copper(II) chloride occurs naturally as the very rare anhydrous mineral tolbachite and the dihydrate eriochalcite.<ref name="xray18">Marlene C. Morris, Howard F. McMurdie, Eloise H. Evans, Boris Paretzkin, Harry S. Parker, and Nicolas C. Panagiotopoulos (1981) Copper chloride hydrate (eriochalcite), in Standard X-ray D... | Copper(II) chloride | Wikipedia | 385 | 1481873 | https://en.wikipedia.org/wiki/Copper%28II%29%20chloride | Physical sciences | Halide salts | Chemistry |
Cannabis (), commonly known as marijuana (), weed, and pot, among other names, is a non-chemically uniform drug from the cannabis plant. Native to Central or South Asia, the cannabis plant has been used as a drug for both recreational and entheogenic purposes and in various traditional medicines for centuries. Tetrahyd... | Cannabis (drug) | Wikipedia | 486 | 1481886 | https://en.wikipedia.org/wiki/Cannabis%20%28drug%29 | Biology and health sciences | Drugs and pharmacology | null |
Cannabis plants have been grown since at least the 3rd millennium BCE and there is evidence of it being smoked for its psychoactive effects around 500 BCE in the Pamir Mountains, Central Asia. Since the 14th century, cannabis has been subject to legal restrictions. The possession, use, and cultivation of cannabis has b... | Cannabis (drug) | Wikipedia | 483 | 1481886 | https://en.wikipedia.org/wiki/Cannabis%20%28drug%29 | Biology and health sciences | Drugs and pharmacology | null |
Recreational
According to DEA Chief Administrative Law Judge, Francis Young, "cannabis is one of the safest therapeutically active substances known to man". Being under the effects of cannabis is usually referred to as being "high". Cannabis consumption has both psychoactive and physiological effects. The "high" experi... | Cannabis (drug) | Wikipedia | 376 | 1481886 | https://en.wikipedia.org/wiki/Cannabis%20%28drug%29 | Biology and health sciences | Drugs and pharmacology | null |
Many different ways to consume cannabis involve heat to decarboxylate THCA into THC; common modes include:
Smoking, involves burning and inhaling cannabinoids ("smoke") from small pipes, bongs (portable versions of hookahs with a water chamber), paper-wrapped joints, tobacco-leaf-wrapped blunts, or the like.
Vaporizi... | Cannabis (drug) | Wikipedia | 496 | 1481886 | https://en.wikipedia.org/wiki/Cannabis%20%28drug%29 | Biology and health sciences | Drugs and pharmacology | null |
Marijuana use in the United States is three times above the global average, but in line with other Western democracies. Forty-four percent of American 12th graders have tried the drug at least once, and the typical age of first-use is 16, similar to the typical age of first-use for alcohol but lower than the first-use ... | Cannabis (drug) | Wikipedia | 483 | 1481886 | https://en.wikipedia.org/wiki/Cannabis%20%28drug%29 | Biology and health sciences | Drugs and pharmacology | null |
Psychological effects
A 2015 meta-analysis found that, although a longer period of abstinence was associated with smaller magnitudes of impairment, both retrospective and prospective memory were impaired in cannabis users. The authors concluded that some, but not all, of the deficits associated with cannabis use were r... | Cannabis (drug) | Wikipedia | 507 | 1481886 | https://en.wikipedia.org/wiki/Cannabis%20%28drug%29 | Biology and health sciences | Drugs and pharmacology | null |
About 9% of those who experiment with marijuana eventually become dependent according to DSM-IV (1994) criteria. A 2013 review estimates daily use is associated with a 10–20% rate of dependence. The highest risk of cannabis dependence is found in those with a history of poor academic achievement, deviant behavior in ch... | Cannabis (drug) | Wikipedia | 422 | 1481886 | https://en.wikipedia.org/wiki/Cannabis%20%28drug%29 | Biology and health sciences | Drugs and pharmacology | null |
Physical
Heavy, long-term exposure to marijuana may have physical, mental, behavioral and social health consequences. It may be "associated with diseases of the liver (particularly with co-existing hepatitis C), lungs, heart, and vasculature". A 2014 review found that while cannabis use may be less harmful than alcohol... | Cannabis (drug) | Wikipedia | 309 | 1481886 | https://en.wikipedia.org/wiki/Cannabis%20%28drug%29 | Biology and health sciences | Drugs and pharmacology | null |
Cannabis smoke contains thousands of organic and inorganic chemical compounds. This tar is chemically similar to that found in tobacco smoke, and over fifty known carcinogens have been identified in cannabis smoke, including; nitrosamines, reactive aldehydes, and polycyclic aromatic hydrocarbons, including benz[a]pyren... | Cannabis (drug) | Wikipedia | 381 | 1481886 | https://en.wikipedia.org/wiki/Cannabis%20%28drug%29 | Biology and health sciences | Drugs and pharmacology | null |
Emergency department visits
Emergency room (ER) admissions associated with cannabis use rose significantly from 2012 to 2016; adolescents from age 12–17 had the highest risk. At one Colorado medical center following legalization, approximately two percent of ER admissions were classified as cannabis users. The symptoms... | Cannabis (drug) | Wikipedia | 422 | 1481886 | https://en.wikipedia.org/wiki/Cannabis%20%28drug%29 | Biology and health sciences | Drugs and pharmacology | null |
Pharmacokinetics
The high lipid-solubility of cannabinoids results in their persisting in the body for long periods of time. Even after a single administration of THC, detectable levels of THC can be found in the body for weeks or longer (depending on the amount administered and the sensitivity of the assessment method... | Cannabis (drug) | Wikipedia | 416 | 1481886 | https://en.wikipedia.org/wiki/Cannabis%20%28drug%29 | Biology and health sciences | Drugs and pharmacology | null |
The Duquenois–Levine test is commonly used as a screening test in the field, but it cannot definitively confirm the presence of cannabis, as a large range of substances have been shown to give false positives. Researchers at John Jay College of Criminal Justice reported that dietary zinc supplements can mask the presen... | Cannabis (drug) | Wikipedia | 488 | 1481886 | https://en.wikipedia.org/wiki/Cannabis%20%28drug%29 | Biology and health sciences | Drugs and pharmacology | null |
Australia's National Cannabis Prevention and Information Centre (NCPIC) states that the buds (infructescences) of the female cannabis plant contain the highest concentration of THC, followed by the leaves. The stalks and seeds have "much lower THC levels". The UN states that the leaves can contain ten times less THC th... | Cannabis (drug) | Wikipedia | 466 | 1481886 | https://en.wikipedia.org/wiki/Cannabis%20%28drug%29 | Biology and health sciences | Drugs and pharmacology | null |
Hashish (also spelled hasheesh, hashisha, or simply hash) is a concentrated resin cake or ball produced from pressed kief, the detached trichomes and fine material that falls off cannabis fruits, flowers and leaves, or from scraping the resin from the surface of the plants and rolling it into balls. It varies in color ... | Cannabis (drug) | Wikipedia | 477 | 1481886 | https://en.wikipedia.org/wiki/Cannabis%20%28drug%29 | Biology and health sciences | Drugs and pharmacology | null |
Cannabis is indigenous to Central or South Asia and its uses for fabric and rope dates back to the Neolithic age in China and Japan. It is unclear when cannabis first became known for its psychoactive properties. The oldest archeological evidence for the burning of cannabis was found in Romanian kurgans dated 3,500 BC,... | Cannabis (drug) | Wikipedia | 478 | 1481886 | https://en.wikipedia.org/wiki/Cannabis%20%28drug%29 | Biology and health sciences | Drugs and pharmacology | null |
Modern history
Cannabis was introduced to the New World by the Spaniards in 1530–1545. Following an 1836–1840 travel in North Africa and the Middle East, French physician Jacques-Joseph Moreau wrote on the psychological effects of cannabis use; he founded the Paris' Club des Hashischins in 1844. In 1842, Irish physicia... | Cannabis (drug) | Wikipedia | 402 | 1481886 | https://en.wikipedia.org/wiki/Cannabis%20%28drug%29 | Biology and health sciences | Drugs and pharmacology | null |
In 1972, the Dutch government divided drugs into more- and less-dangerous categories, with cannabis being in the lesser category. Accordingly, possession of or less was made a misdemeanor. Cannabis has been available for recreational use in coffee shops since 1976. Cannabis products are only sold openly in certain loc... | Cannabis (drug) | Wikipedia | 497 | 1481886 | https://en.wikipedia.org/wiki/Cannabis%20%28drug%29 | Biology and health sciences | Drugs and pharmacology | null |
Since the beginning of the 20th century, most countries have enacted laws against the cultivation, possession or transfer of cannabis. These laws have had an adverse effect on cannabis cultivation for non-recreational purposes, but there are many regions where handling of cannabis is legal or licensed. Many jurisdictio... | Cannabis (drug) | Wikipedia | 502 | 1481886 | https://en.wikipedia.org/wiki/Cannabis%20%28drug%29 | Biology and health sciences | Drugs and pharmacology | null |
In November 2015, Uttarakhand became the first state of India to legalize the cultivation of hemp for industrial purposes. Usage within the Hindu and Buddhist cultures of the Indian subcontinent is common, with many street vendors in India openly selling products infused with cannabis, and traditional medical practitio... | Cannabis (drug) | Wikipedia | 345 | 1481886 | https://en.wikipedia.org/wiki/Cannabis%20%28drug%29 | Biology and health sciences | Drugs and pharmacology | null |
Legal status by country
As of 2022, Uruguay and Canada are the only countries that have fully legalized the cultivation, consumption and bartering of recreational cannabis nationwide. In the United States, 24 states, 3 territories, and the District of Columbia have legalized the recreational use of cannabis – though t... | Cannabis (drug) | Wikipedia | 504 | 1481886 | https://en.wikipedia.org/wiki/Cannabis%20%28drug%29 | Biology and health sciences | Drugs and pharmacology | null |
The average levels of THC in cannabis sold in the United States rose dramatically between the 1970s and 2000. This is disputed for various reasons, and there is little consensus as to whether this is a fact or an artifact of poor testing methodologies. According to Daniel Forbes writing for slate.com, the relative stre... | Cannabis (drug) | Wikipedia | 509 | 1481886 | https://en.wikipedia.org/wiki/Cannabis%20%28drug%29 | Biology and health sciences | Drugs and pharmacology | null |
The gateway hypothesis states that cannabis use increases the probability of trying "harder" drugs. The hypothesis has been hotly debated as it is regarded by some as the primary rationale for the United States prohibition on cannabis use. A Pew Research Center poll found that political opposition to marijuana use was ... | Cannabis (drug) | Wikipedia | 404 | 1481886 | https://en.wikipedia.org/wiki/Cannabis%20%28drug%29 | Biology and health sciences | Drugs and pharmacology | null |
In 2020, the National Institute on Drug Abuse released a study backing allegations that marijuana is a gateway to harder drugs, though not for the majority of marijuana users. The National Institute on Drug Abuse determined that marijuana use is "likely to precede use of other licit and illicit substances" and that "ad... | Cannabis (drug) | Wikipedia | 377 | 1481886 | https://en.wikipedia.org/wiki/Cannabis%20%28drug%29 | Biology and health sciences | Drugs and pharmacology | null |
A carbon planet is a hypothetical type of planet that contains more carbon than oxygen. Carbon is the fourth most abundant element in the universe by mass after hydrogen, helium, and oxygen.
Marc Kuchner and Sara Seager coined the term "carbon planet" in 2005 and investigated such planets following the suggestion of K... | Carbon planet | Wikipedia | 450 | 1483403 | https://en.wikipedia.org/wiki/Carbon%20planet | Physical sciences | Planetary science | Astronomy |
Carbon planets are predicted to be of similar diameter to silicate and water planets of the same mass, potentially making them difficult to distinguish. The equivalents of geologic features on Earth may also be present, but with different compositions. For instance, the rivers might consist of oils. If the temperature ... | Carbon planet | Wikipedia | 339 | 1483403 | https://en.wikipedia.org/wiki/Carbon%20planet | Physical sciences | Planetary science | Astronomy |
Other carbon-rich objects
In August 2011, Matthew Bailes and colleagues from Swinburne University of Technology in Australia reported that the millisecond pulsar PSR J1719-1438 may have a binary companion star that has been crushed into a much smaller planet made largely of solid diamond. They deduced that a small com... | Carbon planet | Wikipedia | 317 | 1483403 | https://en.wikipedia.org/wiki/Carbon%20planet | Physical sciences | Planetary science | Astronomy |
The Belt of Venusalso called Venus's Girdle, the antitwilight arch, or antitwilightis an atmospheric phenomenon visible shortly before sunrise or after sunset, during civil twilight. It is a pinkish glow that surrounds the observer, extending roughly 10–20° above the horizon. It appears opposite to the afterglow, which... | Belt of Venus | Wikipedia | 427 | 3983697 | https://en.wikipedia.org/wiki/Belt%20of%20Venus | Physical sciences | Celestial mechanics | Astronomy |
The late Paleozoic icehouse, also known as the Late Paleozoic Ice Age (LPIA) and formerly known as the Karoo ice age, was an ice age that began in the Late Devonian and ended in the Late Permian, occurring from 360 to 255 million years ago (Mya), and large land-based ice sheets were then present on Earth's surface. It ... | Late Paleozoic icehouse | Wikipedia | 259 | 3988315 | https://en.wikipedia.org/wiki/Late%20Paleozoic%20icehouse | Physical sciences | Events | Earth science |
The first glacial episodes of the LPIA occurred during the late Famennian and the Tournaisian, with δ15N evidence showing that the transition from greenhouse to icehouse was a stepwise process and not an immediate change. These Early Mississippian glaciations were transient and minor, with them sometimes being consider... | Late Paleozoic icehouse | Wikipedia | 507 | 3988315 | https://en.wikipedia.org/wiki/Late%20Paleozoic%20icehouse | Physical sciences | Events | Earth science |
Another long regional interval also limited to Australia from the middle Kungurian to the early Capitanian, known as P3, though unlike the previous glaciations, this one and the following P4 glaciation was largely limited to alpine glaciation. A final regional Australian interval lasted from the middle Capitanian to th... | Late Paleozoic icehouse | Wikipedia | 150 | 3988315 | https://en.wikipedia.org/wiki/Late%20Paleozoic%20icehouse | Physical sciences | Events | Earth science |
The time intervals here referred to as glacial and interglacial periods represented intervals of several million years corresponding to colder and warmer icehouse intervals, respectively, were influenced by long term variations in palaeogeography, greenhouse gas levels, and geological processes such as rates of volcani... | Late Paleozoic icehouse | Wikipedia | 436 | 3988315 | https://en.wikipedia.org/wiki/Late%20Paleozoic%20icehouse | Physical sciences | Events | Earth science |
In southern Victoria Land, Antarctica, the Metschel Tillite, made up of reworked Devonian Beacon Supergroup sedimentary strata along with Cambrian and Ordovician granitoids and some Neoproterozoic metamorphic rocks, preserves glacial sediments indicating the presence of major ice sheets. Northern Victoria Land and Tasm... | Late Paleozoic icehouse | Wikipedia | 320 | 3988315 | https://en.wikipedia.org/wiki/Late%20Paleozoic%20icehouse | Physical sciences | Events | Earth science |
Greenhouse gas reduction
The evolution of plants following the Silurian-Devonian Terrestrial Revolution and the subsequent adaptive radiation of vascular plants on land began a long-term increase in planetary oxygen levels. Large tree ferns, growing to high, were secondarily dominant to the large arborescent lycopods... | Late Paleozoic icehouse | Wikipedia | 506 | 3988315 | https://en.wikipedia.org/wiki/Late%20Paleozoic%20icehouse | Physical sciences | Events | Earth science |
The Mississippian witnessed major uplift in southwestern Gondwana, where the earliest glaciations of the LPIA began. The uplift, driven by mantle dynamics rather than by crustal tectonic processes, is evidenced by the increase in temperature of the southwestern Gondwanan crust as shown by changing compositions of grani... | Late Paleozoic icehouse | Wikipedia | 453 | 3988315 | https://en.wikipedia.org/wiki/Late%20Paleozoic%20icehouse | Physical sciences | Events | Earth science |
Biotic effects
The development of high-frequency, high-amplitude glacioeustasy, which resulted in sea level changes of up to 120 metres between warmer and colder intervals, during the beginning of the LPIA, combined with the increased geographic separation of marine ecoregions and decrease in ocean circulation it caus... | Late Paleozoic icehouse | Wikipedia | 433 | 3988315 | https://en.wikipedia.org/wiki/Late%20Paleozoic%20icehouse | Physical sciences | Events | Earth science |
Once these factors brought a halt and a small reversal in the spread of ice sheets, the lower planetary albedo resulting from the fall in size of the glaciated areas would have been enough for warmer summers and winters and thus limit the depth of snowfields in areas from which the glaciers expanded. Rising sea levels ... | Late Paleozoic icehouse | Wikipedia | 232 | 3988315 | https://en.wikipedia.org/wiki/Late%20Paleozoic%20icehouse | Physical sciences | Events | Earth science |
Tarpon are fish of the genus Megalops. They are the only members of the family Megalopidae. Of the two species, one (M. atlanticus) is native to the Atlantic, and the other (M. cyprinoides) to the Indo-Pacific Oceans.
Species and habitats
The two species of tarpon are M. atlanticus (Atlantic tarpon) and M. cyprinoid... | Tarpon | Wikipedia | 469 | 23210152 | https://en.wikipedia.org/wiki/Tarpon | Biology and health sciences | Anguilliformes | Animals |
Tarpon grow to about long and weigh . They have dorsal and anal soft rays and bluish or greenish backs. Tarpons possess shiny, silvery scales that cover most of their bodies, excluding the head. They have large eyes with adipose eyelids and broad mouths with prominent lower jaws that jut out farther than the rest of t... | Tarpon | Wikipedia | 460 | 23210152 | https://en.wikipedia.org/wiki/Tarpon | Biology and health sciences | Anguilliformes | Animals |
One of the unique features of Megalops is the swim bladder, which, in addition to controlling the buoyancy, can be used as an accessory respiratory organ. It arises dorsally from the posterior pharynx, and the respiratory surface is coated with blood capillaries with a thin epithelium over the top. This is the basis of... | Tarpon | Wikipedia | 478 | 23210152 | https://en.wikipedia.org/wiki/Tarpon | Biology and health sciences | Anguilliformes | Animals |
Geographical distribution and migration
Since tarpon are not commercially valuable as a food fish, very little has been documented concerning their geographical distribution and migrations. They inhabit both sides of the Atlantic Ocean, and their range in the eastern Atlantic has been reliably established from Senegal ... | Tarpon | Wikipedia | 301 | 23210152 | https://en.wikipedia.org/wiki/Tarpon | Biology and health sciences | Anguilliformes | Animals |
The gram per cubic centimetre is a unit of density in the CGS system, and is commonly used in chemistry. It is defined by dividing the CGS unit of mass, the gram, by the CGS unit of volume, the cubic centimetre. The official SI symbols are g/cm3, g·cm−3, or g cm−3. It is equivalent to the units gram per millilitre (g/m... | Gram per cubic centimetre | Wikipedia | 205 | 23215561 | https://en.wikipedia.org/wiki/Gram%20per%20cubic%20centimetre | Physical sciences | Density | Basics and measurement |
In astrophysics, an event horizon is a boundary beyond which events cannot affect an outside observer. Wolfgang Rindler coined the term in the 1950s.
In 1784, John Michell proposed that gravity can be strong enough in the vicinity of massive compact objects that even light cannot escape. At that time, the Newtonian th... | Event horizon | Wikipedia | 452 | 29320146 | https://en.wikipedia.org/wiki/Event%20horizon | Physical sciences | Basics_3 | null |
In cosmology, the event horizon of the observable universe is the largest comoving distance from which light emitted now can ever reach the observer in the future. This differs from the concept of the particle horizon, which represents the largest comoving distance from which light emitted in the past could reach the o... | Event horizon | Wikipedia | 478 | 29320146 | https://en.wikipedia.org/wiki/Event%20horizon | Physical sciences | Basics_3 | null |
For example, this occurs with a uniformly accelerated particle. A spacetime diagram of this situation is shown in the figure to the right. As the particle accelerates, it approaches, but never reaches, the speed of light with respect to its original reference frame. On the spacetime diagram, its path is a hyperbola, wh... | Event horizon | Wikipedia | 367 | 29320146 | https://en.wikipedia.org/wiki/Event%20horizon | Physical sciences | Basics_3 | null |
One of the best-known examples of an event horizon derives from general relativity's description of a black hole, a celestial object so dense that no nearby matter or radiation can escape its gravitational field. Often, this is described as the boundary within which the black hole's escape velocity is greater than the ... | Event horizon | Wikipedia | 422 | 29320146 | https://en.wikipedia.org/wiki/Event%20horizon | Physical sciences | Basics_3 | null |
Black hole event horizons are widely misunderstood. Common, although erroneous, is the notion that black holes "vacuum up" material in their neighborhood, where in fact they are no more capable of seeking out material to consume than any other gravitational attractor. As with any mass in the universe, matter must come ... | Event horizon | Wikipedia | 403 | 29320146 | https://en.wikipedia.org/wiki/Event%20horizon | Physical sciences | Basics_3 | null |
Interacting with black hole horizons
A misconception concerning event horizons, especially black hole event horizons, is that they represent an immutable surface that destroys objects that approach them. In practice, all event horizons appear to be some distance away from any observer, and objects sent towards an event... | Event horizon | Wikipedia | 373 | 29320146 | https://en.wikipedia.org/wiki/Event%20horizon | Physical sciences | Basics_3 | null |
Assuming that the possible apparent horizon is far inside the event horizon, or there is none, observers crossing a black hole event horizon would not actually see or feel anything special happen at that moment. In terms of visual appearance, observers who fall into the hole perceive the eventual apparent horizon as a ... | Event horizon | Wikipedia | 431 | 29320146 | https://en.wikipedia.org/wiki/Event%20horizon | Physical sciences | Basics_3 | null |
An alternative is provided by the complementarity principle, according to which, in the chart of the far observer, infalling matter is thermalized at the horizon and reemitted as Hawking radiation, while in the chart of an infalling observer matter continues undisturbed through the inner region and is destroyed at the ... | Event horizon | Wikipedia | 182 | 29320146 | https://en.wikipedia.org/wiki/Event%20horizon | Physical sciences | Basics_3 | null |
Completeness is a property of the real numbers that, intuitively, implies that there are no "gaps" (in Dedekind's terminology) or "missing points" in the real number line. This contrasts with the rational numbers, whose corresponding number line has a "gap" at each irrational value. In the decimal number system, comp... | Completeness of the real numbers | Wikipedia | 505 | 29322627 | https://en.wikipedia.org/wiki/Completeness%20of%20the%20real%20numbers | Mathematics | Real analysis | null |
The least upper bound property can be generalized to the setting of partially ordered sets. See completeness (order theory).
Dedekind completeness
Dedekind completeness is the property that every Dedekind cut of the real numbers is generated by a real number. In a synthetic approach to the real numbers, this is the ... | Completeness of the real numbers | Wikipedia | 502 | 29322627 | https://en.wikipedia.org/wiki/Completeness%20of%20the%20real%20numbers | Mathematics | Real analysis | null |
The rational number line does not satisfy the nested interval theorem. For example, the sequence (whose terms are derived from the digits of pi in the suggested way)
is a nested sequence of closed intervals in the rational numbers whose intersection is empty. (In the real numbers, the intersection of these intervals... | Completeness of the real numbers | Wikipedia | 491 | 29322627 | https://en.wikipedia.org/wiki/Completeness%20of%20the%20real%20numbers | Mathematics | Real analysis | null |
A walnut is the edible seed of any tree of the genus Juglans (family Juglandaceae), particularly the Persian or English walnut, Juglans regia. They are accessory fruit because the outer covering of the fruit is technically an involucre and thus not morphologically part of the carpel; this means it cannot be a drupe but... | Walnut | Wikipedia | 433 | 30826411 | https://en.wikipedia.org/wiki/Walnut | Biology and health sciences | Fagales | null |
Species
The three species of walnuts most commonly grown for their seeds are the Persian (or English) walnut (J. regia), originating from Iran, the black walnut (J. nigra) – native to eastern North America – and the Japanese walnut, also known as the heartnut (J. ailantifolia). Other species include J. californica, th... | Walnut | Wikipedia | 469 | 30826411 | https://en.wikipedia.org/wiki/Walnut | Biology and health sciences | Fagales | null |
In 2022, world production of walnuts (in shell) was 3.9 million tonnes, with China contributing 36% of the total (table). Other significant producers (in the order of decreasing harvest) were the United States, Iran, and Turkey.
Nutrition
English walnuts without shells are 4% water, 15% protein, 65% fat, and 14% carb... | Walnut | Wikipedia | 491 | 30826411 | https://en.wikipedia.org/wiki/Walnut | Biology and health sciences | Fagales | null |
Walnut meats are available in two forms: in their shells or de-shelled. Due to processing, the meats may be whole, halved, or in smaller portions. All walnuts can be eaten on their own (raw, toasted, or pickled), or as part of a mix such as muesli, or as an ingredient of a dish: e.g. walnut soup, walnut pie, walnut cof... | Walnut | Wikipedia | 497 | 30826411 | https://en.wikipedia.org/wiki/Walnut | Biology and health sciences | Fagales | null |
Cat litter
At least two companies, LitterMaid and Naturally Fresh, make cat litter from ground walnut shells. Advantages cited over conventional clay litter include environmental sustainability of using what would otherwise be a waste product, superior natural biodegradability, and odor control as good or better than ... | Walnut | Wikipedia | 230 | 30826411 | https://en.wikipedia.org/wiki/Walnut | Biology and health sciences | Fagales | null |
The ISCC–NBS System of Color Designation is a system for naming colors based on a set of 13 basic color terms and a small set of adjective modifiers. It was first established in the 1930s by a joint effort of the Inter-Society Color Council (ISCC), made up of delegates from various American trade organizations, and the... | ISCC–NBS system | Wikipedia | 337 | 27973777 | https://en.wikipedia.org/wiki/ISCC%E2%80%93NBS%20system | Physical sciences | Basics | Physics |
After the definition of the Munsell system was slightly altered by its 1943 renotations, the ISCC–NBS system was redefined in the 1950s in relation to the new Munsell coordinates. In 1955, the NBS published The Color Names Dictionary, which cross-referenced terms from several other color systems and dictionaries, relat... | ISCC–NBS system | Wikipedia | 431 | 27973777 | https://en.wikipedia.org/wiki/ISCC%E2%80%93NBS%20system | Physical sciences | Basics | Physics |
The Color Names Dictionary
One of the primary original goals of the ISCC–NBS system was to relate several other common color systems and charts to a common frame of reference. To that end, in the late 1940s, the creators of the ISCC–NBS system measured several other significant color standards and charts, either spect... | ISCC–NBS system | Wikipedia | 356 | 27973777 | https://en.wikipedia.org/wiki/ISCC%E2%80%93NBS%20system | Physical sciences | Basics | Physics |
Aerospace engineering is the primary field of engineering concerned with the development of aircraft and spacecraft. It has two major and overlapping branches: aeronautical engineering and astronautical engineering. Avionics engineering is similar, but deals with the electronics side of aerospace engineering.
"Aeron... | Aerospace engineering | Wikipedia | 503 | 21732545 | https://en.wikipedia.org/wiki/Aerospace%20engineering | Technology | Disciplines | null |
Between World Wars I and II, great leaps were made in the field, accelerated by the advent of mainstream civil aviation. Notable airplanes of this era include the Curtiss JN 4, Farman F.60 Goliath, and Fokker Trimotor. Notable military airplanes of this period include the Mitsubishi A6M Zero, Supermarine Spitfire and M... | Aerospace engineering | Wikipedia | 447 | 21732545 | https://en.wikipedia.org/wiki/Aerospace%20engineering | Technology | Disciplines | null |
On October 25, 2007, the Airbus A380 made its maiden commercial flight from Singapore to Sydney, Australia. This aircraft was the first passenger plane to surpass the Boeing 747 in terms of passenger capacity, with a maximum of 853. Though development of this aircraft began in 1988 as a competitor to the 747, the A380 ... | Aerospace engineering | Wikipedia | 78 | 21732545 | https://en.wikipedia.org/wiki/Aerospace%20engineering | Technology | Disciplines | null |
Some of the elements of aerospace engineering are:
Radar cross-section – the study of vehicle signature apparent to remote sensing by radar.
Fluid mechanics – the study of fluid flow around objects. Specifically aerodynamics concerning the flow of air over bodies such as wings or through objects such as wind tunnels ... | Aerospace engineering | Wikipedia | 499 | 21732545 | https://en.wikipedia.org/wiki/Aerospace%20engineering | Technology | Disciplines | null |
Risk and reliability – the study of risk and reliability assessment techniques and the mathematics involved in the quantitative methods.
Noise control – the study of the mechanics of sound transfer.
Aeroacoustics – the study of noise generation via either turbulent fluid motion or aerodynamic forces interacting with ... | Aerospace engineering | Wikipedia | 92 | 21732545 | https://en.wikipedia.org/wiki/Aerospace%20engineering | Technology | Disciplines | null |
The basis of most of these elements lies in theoretical physics, such as fluid dynamics for aerodynamics or the equations of motion for flight dynamics. There is also a large empirical component. Historically, this empirical component was derived from testing of scale models and prototypes, either in wind tunnels or in... | Aerospace engineering | Wikipedia | 414 | 21732545 | https://en.wikipedia.org/wiki/Aerospace%20engineering | Technology | Disciplines | null |
In the mathematical field of graph theory, the Coxeter graph is a 3-regular graph with 28 vertices and 42 edges. It is one of the 13 known cubic distance-regular graphs. It is named after Harold Scott MacDonald Coxeter.
Properties
The Coxeter graph has chromatic number 3, chromatic index 3, radius 4, diameter 4 and gi... | Coxeter graph | Wikipedia | 499 | 5358570 | https://en.wikipedia.org/wiki/Coxeter%20graph | Mathematics | Graph theory | null |
As a finite connected vertex-transitive graph that contains no Hamiltonian cycle, the Coxeter graph is a counterexample to a variant of the Lovász conjecture, but the canonical formulation of the conjecture asks for an Hamiltonian path and is verified by the Coxeter graph.
Only five examples of vertex-transitive graph... | Coxeter graph | Wikipedia | 203 | 5358570 | https://en.wikipedia.org/wiki/Coxeter%20graph | Mathematics | Graph theory | null |
The nurse shark (Ginglymostoma cirratum) is an elasmobranch fish in the family Ginglymostomatidae. The conservation status of the nurse shark is globally assessed as Vulnerable in the IUCN List of Threatened Species. They are considered to be a species of least concern in the United States and in The Bahamas, but consi... | Nurse shark | Wikipedia | 442 | 5363452 | https://en.wikipedia.org/wiki/Nurse%20shark | Biology and health sciences | Sharks | null |
Distribution and habitat
The nurse shark has a wide but patchy geographical distribution along tropical and subtropical coastal waters of the Eastern Atlantic, Western Atlantic, and Eastern Pacific. In the Eastern Atlantic it ranges from Cape Verde to Gabon (accidental north to France). In the Western Atlantic, includi... | Nurse shark | Wikipedia | 434 | 5363452 | https://en.wikipedia.org/wiki/Nurse%20shark | Biology and health sciences | Sharks | null |
Reproduction
Nurse sharks are ovoviviparous, with fertilized eggs hatching inside the female. The mating cycle of nurse sharks is biennial, with females taking up to 18 months to produce a new batch of eggs. The mating season runs from late June to the end of July, with a gestation period of six months and a typical li... | Nurse shark | Wikipedia | 170 | 5363452 | https://en.wikipedia.org/wiki/Nurse%20shark | Biology and health sciences | Sharks | null |
In mathematics and physics, vector is a term that refers to quantities that cannot be expressed by a single number (a scalar), or to elements of some vector spaces. They have to be expressed by both magnitude and direction.
Historically, vectors were introduced in geometry and physics (typically in mechanics) for quan... | Vector (mathematics and physics) | Wikipedia | 511 | 23218956 | https://en.wikipedia.org/wiki/Vector%20%28mathematics%20and%20physics%29 | Mathematics | Linear algebra | null |
The set of tuples of real numbers has a natural structure of vector space defined by component-wise addition and scalar multiplication. It is common to call these tuples vectors, even in contexts where vector-space operations do not apply. More generally, when some data can be represented naturally by vectors, they a... | Vector (mathematics and physics) | Wikipedia | 410 | 23218956 | https://en.wikipedia.org/wiki/Vector%20%28mathematics%20and%20physics%29 | Mathematics | Linear algebra | null |
In botany, a berry is a fleshy fruit without a stone (pit) produced from a single flower containing one ovary. Berries so defined include grapes, currants, and tomatoes, as well as cucumbers, eggplants (aubergines), persimmons and bananas, but exclude certain fruits that meet the culinary definition of berries, such as... | Berry (botany) | Wikipedia | 495 | 3991810 | https://en.wikipedia.org/wiki/Berry%20%28botany%29 | Biology and health sciences | Plant: General | null |
The nature of the endocarp distinguishes a berry from a drupe, which has a hardened or stony endocarp (see also below). The two kinds of fruit intergrade, depending on the state of the endocarp. Some sources have attempted to quantify the difference, e.g. requiring the endocarp to be less than 2 mm thick in a berry.
E... | Berry (botany) | Wikipedia | 452 | 3991810 | https://en.wikipedia.org/wiki/Berry%20%28botany%29 | Biology and health sciences | Plant: General | null |
"True berries", or "baccae", may also be required to have a thin outer skin, not self-supporting when removed from the berry. This distinguishes, for example, a Vaccinium or Solanum berry from an Adansonia (baobab) amphisarca, which has a dry, more rigid and self-supporting skin. The fruit of citrus, such as the orange... | Berry (botany) | Wikipedia | 385 | 3991810 | https://en.wikipedia.org/wiki/Berry%20%28botany%29 | Biology and health sciences | Plant: General | null |
Drupes are varyingly distinguished from botanical berries. Drupes are fleshy fruits produced from a (usually) single-seeded ovary with a hard woody layer (called the endocarp) surrounding the seed. Familiar examples include the stonefruits of the genus Prunus (peaches, plums and cherries), olives, coconut, dates, baybe... | Berry (botany) | Wikipedia | 498 | 3991810 | https://en.wikipedia.org/wiki/Berry%20%28botany%29 | Biology and health sciences | Plant: General | null |
Accessory fruits are not botanical berries. In accessory fruits, the edible part is not generated by the ovary. Berry-like examples include:
Strawberry – the non-fleshy aggregate of seed-like achenes on its exterior is actually the "fruit", derived from an aggregate of ovaries; the fleshy part develops instead from th... | Berry (botany) | Wikipedia | 359 | 3991810 | https://en.wikipedia.org/wiki/Berry%20%28botany%29 | Biology and health sciences | Plant: General | null |
In 1751, Carl Linnaeus wrote Philosophia Botanica, considered to be the first textbook of descriptive systematic botany. He used eight different terms for fruits, one of which was or berry, distinguished from other types of fruit such as (drupe) and (pome). A was defined as "", meaning "unvalved solid pericarp, con... | Berry (botany) | Wikipedia | 429 | 3991810 | https://en.wikipedia.org/wiki/Berry%20%28botany%29 | Biology and health sciences | Plant: General | null |
By definition, berries have a fleshy, indehiscent pericarp, as opposed to a dry, dehiscent pericarp. Fossils show that early flowering plants had dry fruits; fleshy fruits, such as berries or drupes, appeared only towards the end of the Cretaceous Period or the beginning of the Paleogene Period, about . The increasing ... | Berry (botany) | Wikipedia | 509 | 3991810 | https://en.wikipedia.org/wiki/Berry%20%28botany%29 | Biology and health sciences | Plant: General | null |
Berries, defined loosely, have been valuable as a food source to humans since before the start of agriculture, and remain among the primary food sources of other primates. Botanically defined berries with culinary uses include:
Berries in the strictest sense: including bananas and plantains, blueberries, cranberries, ... | Berry (botany) | Wikipedia | 409 | 3991810 | https://en.wikipedia.org/wiki/Berry%20%28botany%29 | Biology and health sciences | Plant: General | null |
History
Cucurbit berries or pepos, particularly from Cucurbita and Lagenaria, are the earliest plants known to be domesticated – before 9,000–10,000 BP in the Americas, and probably by 12,000–13,000 BP in Asia. Peppers were domesticated in Mesoamerica by 8,000 BP. Many other early cultivated plants were also berries by... | Berry (botany) | Wikipedia | 346 | 3991810 | https://en.wikipedia.org/wiki/Berry%20%28botany%29 | Biology and health sciences | Plant: General | null |
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