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Anthracotheriidae is a paraphyletic family of extinct, hippopotamus-like artiodactyl ungulates related to hippopotamuses and whales. The oldest genus, Elomeryx, first appeared during the middle Eocene in Asia. They thrived in Africa and Eurasia, with a few species ultimately entering North America during the Oligocene.... | Anthracotheriidae | Wikipedia | 486 | 8686104 | https://en.wikipedia.org/wiki/Anthracotheriidae | Biology and health sciences | Other artiodactyla | Animals | vital_articles |
Recent evidence, gained from comparative gene sequencing, further suggests that hippos are the closest living relatives of whales, so, if anthracotheres are stem hippos, they would also be related to whales in a clade provisionally called Whippomorpha.
However, the earliest known anthracotheres appear in the fossil re... | Anthracotheriidae | Wikipedia | 292 | 8686104 | https://en.wikipedia.org/wiki/Anthracotheriidae | Biology and health sciences | Other artiodactyla | Animals | vital_articles |
Hammond's postulate (or alternatively the Hammond–Leffler postulate), is a hypothesis in physical organic chemistry which describes the geometric structure of the transition state in an organic chemical reaction. First proposed by George Hammond in 1955, the postulate states that:
If two states, as, for example, a tra... | Hammond's postulate | Wikipedia | 427 | 4131678 | https://en.wikipedia.org/wiki/Hammond%27s%20postulate | Physical sciences | Kinetics | Chemistry | vital_articles |
History
During the 1940s and 1950s, chemists had trouble explaining why even slight changes in the reactants caused significant differences in the rate and product distributions of a reaction. In 1955 George Hammond, a young professor at Iowa State University, postulated that transition-state theory could be used to q... | Hammond's postulate | Wikipedia | 415 | 4131678 | https://en.wikipedia.org/wiki/Hammond%27s%20postulate | Physical sciences | Kinetics | Chemistry | vital_articles |
An example of the “early” transition state is chlorination. Chlorination favors the products because it is an exothermic reaction, which means that the products are lower in energy than the reactants. When looking at the adjacent diagram (representation of an "early" transition state), one must focus on the transition ... | Hammond's postulate | Wikipedia | 393 | 4131678 | https://en.wikipedia.org/wiki/Hammond%27s%20postulate | Physical sciences | Kinetics | Chemistry | vital_articles |
Therefore, since the tertiary carbocation is relatively stable and therefore close in energy to the R-X reactant, then the tertiary transition state will have a structure that is fairly similar to the R-X reactant. In terms of the graph of reaction coordinate versus energy, this is shown by the fact that the tertiary ... | Hammond's postulate | Wikipedia | 437 | 4131678 | https://en.wikipedia.org/wiki/Hammond%27s%20postulate | Physical sciences | Kinetics | Chemistry | vital_articles |
E2 reactions
Elimination, bimolecular reactions are one step, concerted reaction where both base and substrate participate in the rate limiting step. In an E2 mechanism, a base takes a proton near the leaving group, forcing the electrons down to make a double bond, and forcing off the leaving group-all in one concerte... | Hammond's postulate | Wikipedia | 506 | 4131678 | https://en.wikipedia.org/wiki/Hammond%27s%20postulate | Physical sciences | Kinetics | Chemistry | vital_articles |
First, consider the reaction at secondary and tertiary carbons. As the BEP principle notes, experimentally SN1 reactions at tertiary carbons are faster than at secondary carbons. Therefore, by definition, the transition state for tertiary reactions will be at a lower energy than for secondary reactions. However, the... | Hammond's postulate | Wikipedia | 416 | 4131678 | https://en.wikipedia.org/wiki/Hammond%27s%20postulate | Physical sciences | Kinetics | Chemistry | vital_articles |
Explaining seemingly contradictory results
Hammond's postulate is especially important when looking at the rate-limiting step of a reaction. However, one must be cautious when examining a multistep reaction or one with the possibility of rearrangements during an intermediate stage. In some cases, the final products ap... | Hammond's postulate | Wikipedia | 272 | 4131678 | https://en.wikipedia.org/wiki/Hammond%27s%20postulate | Physical sciences | Kinetics | Chemistry | vital_articles |
Ultrafast laser spectroscopy is a category of spectroscopic techniques using ultrashort pulse lasers for the study of dynamics on extremely short time scales (attoseconds to nanoseconds). Different methods are used to examine the dynamics of charge carriers, atoms, and molecules. Many different procedures have been dev... | Ultrafast laser spectroscopy | Wikipedia | 499 | 4136723 | https://en.wikipedia.org/wiki/Ultrafast%20laser%20spectroscopy | Physical sciences | Spectroscopy | Chemistry | vital_articles |
Fiber laser
A fiber laser is usually generated first from a laser diode. The laser diode then couples the light into a fiber where it will be confined. Different wavelengths can be achieved with the use of doped fiber. The pump light from the laser diode will excite a state in the doped fiber which can then drop in ene... | Ultrafast laser spectroscopy | Wikipedia | 386 | 4136723 | https://en.wikipedia.org/wiki/Ultrafast%20laser%20spectroscopy | Physical sciences | Spectroscopy | Chemistry | vital_articles |
Pulse shaping
Pulse shaping is to modify the pulses from the source in a well-defined manner, including manipulation on pulse’s amplitude, phase, and duration.
To amplify pulse’s intensity, chirped pulse amplification is generally employed, which includes a pulse stretcher, amplifier, and compressor. It will not change... | Ultrafast laser spectroscopy | Wikipedia | 484 | 4136723 | https://en.wikipedia.org/wiki/Ultrafast%20laser%20spectroscopy | Physical sciences | Spectroscopy | Chemistry | vital_articles |
Frequency conversion techniques
Different spectroscopy experiments require different excitation or probe wavelengths. For this reason, frequency conversion techniques are commonly used to extend the operational spectrum of existing laser light sources.
The most widespread conversion techniques rely on using crystals wi... | Ultrafast laser spectroscopy | Wikipedia | 205 | 4136723 | https://en.wikipedia.org/wiki/Ultrafast%20laser%20spectroscopy | Physical sciences | Spectroscopy | Chemistry | vital_articles |
Ultrafast transient absorption
This method is typical of 'pump-probe' experiments, where a pulsed laser is used to excite the electrons in a material (such as a molecule or semiconducting solid) from their ground states to higher-energy excited states. A probing light source, typically a xenon arc lamp or broadband las... | Ultrafast laser spectroscopy | Wikipedia | 353 | 4136723 | https://en.wikipedia.org/wiki/Ultrafast%20laser%20spectroscopy | Physical sciences | Spectroscopy | Chemistry | vital_articles |
Ultrafast transient absorption can use almost any probe light, so long as the probe is of a pertinent wavelength or set of wavelengths. A monochromator and photomultiplier tube in place of the avalanche photodiode array allows observation of a single probe wavelength, and thus allows probing of the decay kinetics of th... | Ultrafast laser spectroscopy | Wikipedia | 380 | 4136723 | https://en.wikipedia.org/wiki/Ultrafast%20laser%20spectroscopy | Physical sciences | Spectroscopy | Chemistry | vital_articles |
Time-resolved photoelectron spectroscopy and two-photon photoelectron spectroscopy
Time-resolved photoelectron spectroscopy and two-photon photoelectron spectroscopy (2PPE) combine a pump-probe scheme with angle-resolved photoemission. A first laser pulse is used to excite a material, a second laser pulse ionizes the s... | Ultrafast laser spectroscopy | Wikipedia | 448 | 4136723 | https://en.wikipedia.org/wiki/Ultrafast%20laser%20spectroscopy | Physical sciences | Spectroscopy | Chemistry | vital_articles |
2D spectroscopy using ultrafast pulses can be combined with complementary experimental methods to characterize the system under study. Photoelectrochemical measurements of photosynthetic complexes have been correlated with ultrafast pulses to stimulate and probe chromophores involved in photosynthesis and to characteri... | Ultrafast laser spectroscopy | Wikipedia | 370 | 4136723 | https://en.wikipedia.org/wiki/Ultrafast%20laser%20spectroscopy | Physical sciences | Spectroscopy | Chemistry | vital_articles |
Applications of femtosecond spectroscopy to biochemistry
Ultrafast processes are found throughout biology. Until the advent of femtosecond methods, many of the mechanism of such processes were unknown. Examples of these include the cis-trans photoisomerization of the rhodopsin chromophore retinal, excited state and pop... | Ultrafast laser spectroscopy | Wikipedia | 434 | 4136723 | https://en.wikipedia.org/wiki/Ultrafast%20laser%20spectroscopy | Physical sciences | Spectroscopy | Chemistry | vital_articles |
Time-correlated single photon counting
Time-correlated single photon counting (TCSPC) is used to analyze the relaxation of molecules from an excited state to a lower energy state. Since various molecules in a sample will emit photons at different times following their simultaneous excitation, the decay must be thought ... | Ultrafast laser spectroscopy | Wikipedia | 482 | 4136723 | https://en.wikipedia.org/wiki/Ultrafast%20laser%20spectroscopy | Physical sciences | Spectroscopy | Chemistry | vital_articles |
This electrical pulse comes after the second laser pulse excites the molecule to a higher energy state, and a photon is eventually emitted from a single molecule upon returning to its original state. Thus, the longer a molecule takes to emit a photon, the higher the voltage of the resulting pulse. The central concept o... | Ultrafast laser spectroscopy | Wikipedia | 488 | 4136723 | https://en.wikipedia.org/wiki/Ultrafast%20laser%20spectroscopy | Physical sciences | Spectroscopy | Chemistry | vital_articles |
TCSPC has extensive applications in fluorescence spectroscopy, microscopy (FLIM), and optical tomography. Over the years, this technique has gained significant attention for studying the fluorescence decay of various classes of molecules, including the fluorescence decay of residues in biological systems. The modulatio... | Ultrafast laser spectroscopy | Wikipedia | 138 | 4136723 | https://en.wikipedia.org/wiki/Ultrafast%20laser%20spectroscopy | Physical sciences | Spectroscopy | Chemistry | vital_articles |
A pyeong (abbreviationpy) is a Korean unit of area and floorspace, equal to a square kan or 36square Korean feet. The ping and tsubo are its equivalent Taiwanese and Japanese units, similarly based on a square bu (ja:步) or ken, equivalent to 36square Chinese or Japanese feet.
Current use
Korea
In Korea, the period of... | Pyeong | Wikipedia | 393 | 4137557 | https://en.wikipedia.org/wiki/Pyeong | Physical sciences | Area | Basics and measurement | vital_articles |
Chemical decomposition, or chemical breakdown, is the process or effect of simplifying a single chemical entity (normal molecule, reaction intermediate, etc.) into two or more fragments. Chemical decomposition is usually regarded and defined as the exact opposite of chemical synthesis. In short, the chemical reaction i... | Chemical decomposition | Wikipedia | 483 | 1533184 | https://en.wikipedia.org/wiki/Chemical%20decomposition | Physical sciences | Other reactions | Chemistry | vital_articles |
Other reactions involving decomposition do require the input of external energy. This energy can be in the form of heat, radiation, electricity, or light. The latter being the reason some chemical compounds, such as many prescription medicines, are kept and stored in dark bottles which reduce or eliminate the possibili... | Chemical decomposition | Wikipedia | 284 | 1533184 | https://en.wikipedia.org/wiki/Chemical%20decomposition | Physical sciences | Other reactions | Chemistry | vital_articles |
The needle-gun was a 19th-century military breech-loading rifle, as well as the first breech-loading rifle to use a bolt action to open and close the chamber. It was used as the main infantry weapon of the Prussians in the Wars of German Unification. It was invented in 1836 by the German gunsmith Johann Nikolaus von D... | Dreyse needle gun | Wikipedia | 509 | 1533521 | https://en.wikipedia.org/wiki/Dreyse%20needle%20gun | Technology | Specific firearms | null | vital_articles |
The British Army evaluated the Dreyse needle gun in 1849–1851. In the British trials, the Dreyse was shown to be capable of six rounds per minute, and to maintain accuracy at . The trials suggested that the Dreyse was "too complicated and delicate" for service use. The French muzzle-loading rifle was judged to be a b... | Dreyse needle gun | Wikipedia | 430 | 1533521 | https://en.wikipedia.org/wiki/Dreyse%20needle%20gun | Technology | Specific firearms | null | vital_articles |
The cartridge used with this rifle consisted of the paper case, the bullet, the percussion cap and the black powder charge. The 15.4 mm (0.61 in) bullet was shaped like an acorn, with the broader end forming a point and the primer attached to its base. The bullet was held in a paper case known as a sabot, which separat... | Dreyse needle gun | Wikipedia | 512 | 1533521 | https://en.wikipedia.org/wiki/Dreyse%20needle%20gun | Technology | Specific firearms | null | vital_articles |
The placement of the primer directly behind the bullet meant the firing needle was enclosed in black powder when the gun was fired, causing stress to the pin, which could break over time and render the rifle useless until it could be replaced. Soldiers were provided with two replacement needles for that purpose. The ne... | Dreyse needle gun | Wikipedia | 186 | 1533521 | https://en.wikipedia.org/wiki/Dreyse%20needle%20gun | Technology | Specific firearms | null | vital_articles |
Ammonium sulfate (American English and international scientific usage; ammonium sulphate in British English); (NH4)2SO4, is an inorganic salt with a number of commercial uses. The most common use is as a soil fertilizer. It contains 21% nitrogen and 24% sulfur.
Uses
Agriculture
The primary use of ammonium sulfate is ... | Ammonium sulfate | Wikipedia | 497 | 1536137 | https://en.wikipedia.org/wiki/Ammonium%20sulfate | Physical sciences | Salts | null | vital_articles |
Other uses
Ammonium sulfate is a precursor to other ammonium salts, especially ammonium persulfate.
Ammonium sulfate is listed as an ingredient for many United States vaccines per the Centers for Disease Control.
Ammonium sulfate has also been used in flame retardant compositions acting much like diammonium phosphat... | Ammonium sulfate | Wikipedia | 458 | 1536137 | https://en.wikipedia.org/wiki/Ammonium%20sulfate | Physical sciences | Salts | null | vital_articles |
As a salt of a strong acid (H2SO4) and weak base (NH3), its solution is acidic; the pH of 0.1 M solution is 5.5. In aqueous solution the reactions are those of and ions. For example, addition of barium chloride, precipitates out barium sulfate. The filtrate on evaporation yields ammonium chloride.
Ammonium sulfate f... | Ammonium sulfate | Wikipedia | 350 | 1536137 | https://en.wikipedia.org/wiki/Ammonium%20sulfate | Physical sciences | Salts | null | vital_articles |
In modern models of physical cosmology, a dark matter halo is a basic unit of cosmological structure. It is a hypothetical region that has decoupled from cosmic expansion and contains gravitationally bound matter.
A single dark matter halo may contain multiple virialized clumps of dark matter bound together by gravit... | Dark matter halo | Wikipedia | 466 | 1539785 | https://en.wikipedia.org/wiki/Dark%20matter%20halo | Physical sciences | Basics_2 | Astronomy | vital_articles |
The formation of dark matter halos is believed to have played a major role in the early formation of galaxies. During initial galactic formation, the temperature of the baryonic matter should have still been much too high for it to form gravitationally self-bound objects, thus requiring the prior formation of dark matt... | Dark matter halo | Wikipedia | 437 | 1539785 | https://en.wikipedia.org/wiki/Dark%20matter%20halo | Physical sciences | Basics_2 | Astronomy | vital_articles |
where denotes the finite central density and the core radius. This provides a good fit to most rotation curve data. However, it cannot be a complete description, as the enclosed mass fails to converge to a finite value as the radius tends to infinity. The isothermal model is, at best, an approximation. Many effects m... | Dark matter halo | Wikipedia | 454 | 1539785 | https://en.wikipedia.org/wiki/Dark%20matter%20halo | Physical sciences | Basics_2 | Astronomy | vital_articles |
The collapse of overdensities in the cosmic density field is generally aspherical. So, there is no reason to expect the resulting halos to be spherical. Even the earliest simulations of structure formation in a CDM universe emphasized that the halos are substantially flattened. Subsequent work has shown that halo equid... | Dark matter halo | Wikipedia | 413 | 1539785 | https://en.wikipedia.org/wiki/Dark%20matter%20halo | Physical sciences | Basics_2 | Astronomy | vital_articles |
Milky Way dark matter halo
The visible disk of the Milky Way Galaxy is thought to be embedded in a much larger, roughly spherical halo of dark matter. The dark matter density drops off with distance from the galactic center. It is now believed that about 95% of the galaxy is composed of dark matter, a type of matter ... | Dark matter halo | Wikipedia | 164 | 1539785 | https://en.wikipedia.org/wiki/Dark%20matter%20halo | Physical sciences | Basics_2 | Astronomy | vital_articles |
Madtsoiidae is an extinct family of mostly Gondwanan snakes with a fossil record extending from early Cenomanian (Upper Cretaceous) to late Pleistocene strata located in South America, Africa, India, Australia and Southern Europe. Madtsoiidae include very primitive snakes, which like extant boas and pythons would likel... | Madtsoiidae | Wikipedia | 194 | 9337873 | https://en.wikipedia.org/wiki/Madtsoiidae | Biology and health sciences | Prehistoric squamates | Animals | vital_articles |
Madtsoiidae was first classified as a subfamily of Boidae, Madtsoiinae, in Hoffstetter (1961). Further study and new finds allowed ranking the group as a distinct family in Linnaean systems. With the recent use of cladistics to unravel phylogeny, various analyses have posited Madtsoiidae as a likely clade within Serpen... | Madtsoiidae | Wikipedia | 332 | 9337873 | https://en.wikipedia.org/wiki/Madtsoiidae | Biology and health sciences | Prehistoric squamates | Animals | vital_articles |
Like most fossil snakes the majority of madtsoiids are known only from isolated vertebrae, but several (Madtsoia bai, M. camposi, Wonambi naracoortensis, Nanowana spp., unnamed Yurlunggur spp., Najash rionegrina) have associated or articulated parts of skeletons. Of the genera listed below, all have been referred to M... | Madtsoiidae | Wikipedia | 183 | 9337873 | https://en.wikipedia.org/wiki/Madtsoiidae | Biology and health sciences | Prehistoric squamates | Animals | vital_articles |
Rieppel et al. (2002) classified Wonambi naracoortensis within the extant radiation (crown group) of snakes as Macrostomata incertae sedis, but many of their character state attributions for this species have been criticised or refuted by Scanlon (2005) and the better-preserved skulls of Yurlunggur sp./spp. have numero... | Madtsoiidae | Wikipedia | 507 | 9337873 | https://en.wikipedia.org/wiki/Madtsoiidae | Biology and health sciences | Prehistoric squamates | Animals | vital_articles |
A 2022 morphological study found Madtsoiidae to be paraphyletic, with Sanajeh being found to be the most basal member of the Ophidia, whereas the Cenozoic Australian madtsoiids were basal alethinophidians.
Classification | Madtsoiidae | Wikipedia | 56 | 9337873 | https://en.wikipedia.org/wiki/Madtsoiidae | Biology and health sciences | Prehistoric squamates | Animals | vital_articles |
Gigantophis Andrews, 1901
Gigantophis garstini Andrews, 1901 (Andrews, 1906; Hoffstetter, 1961b; Paleogene, Late Eocene; Egypt (Birket Qarun and Qasr el-Sagha Formations), Libya)
Madtsoia Simpson, 1933
Madtsoia bai Simpson, 1933 (Paleogene, Early Eocene Sarmiento Formation; Argentina)
Madtsoia cf. M. bai (Simpson, ... | Madtsoiidae | Wikipedia | 509 | 9337873 | https://en.wikipedia.org/wiki/Madtsoiidae | Biology and health sciences | Prehistoric squamates | Animals | vital_articles |
Yurlunggur camfieldensis Scanlon, 1992 (Neogene, middle Miocene Bullock Creek (Northern Territory); Australia)
Yurlunggur spp. (Scanlon, 2004; 2006; Paleogene-Neogene, Oligocene to Miocene; Australia)
Herensugea Rage, 1996
Herensugea caristiorum Rage, 1996 (Cretaceous, Campanian or Maastrichtian Vitoria Formation; S... | Madtsoiidae | Wikipedia | 507 | 9337873 | https://en.wikipedia.org/wiki/Madtsoiidae | Biology and health sciences | Prehistoric squamates | Animals | vital_articles |
Unnamed specimens
Madtsoiidae indet. (Rage, 1987; Paleogene, Paleocene; Morocco)
Madtsoiidae indet. (Werner and Rage, 1994, Rage and Werner 1999; Cretaceous, Cenomanian; Sudan)
?Madtsoiid (Rage and Prasad, 1992; Cretaceous, Maastrichtian; India)
?Madtsoiid (Rage, 1991; Paleogene, early Paleocene Santa Lucía Formatio... | Madtsoiidae | Wikipedia | 266 | 9337873 | https://en.wikipedia.org/wiki/Madtsoiidae | Biology and health sciences | Prehistoric squamates | Animals | vital_articles |
Magnesium citrates are metal-organic compounds formed from citrate and magnesium ions. They are salts. One form is the 1:1 magnesium preparation in salt form with citric acid in a 1:1 ratio (1 magnesium atom per citrate molecule). It contains 11.33% magnesium by weight. Magnesium citrate (sensu lato) is used medicin... | Magnesium citrate | Wikipedia | 449 | 9339120 | https://en.wikipedia.org/wiki/Magnesium%20citrate | Physical sciences | Citrates | Chemistry | vital_articles |
Use and dosage
The maximum upper tolerance limit (UTL) for magnesium in supplement form for adults is 350 mg of elemental magnesium per day, according to the National Institutes of Health (NIH). In addition, according to the NIH, total dietary requirements for magnesium from all sources (in other words, food and suppl... | Magnesium citrate | Wikipedia | 327 | 9339120 | https://en.wikipedia.org/wiki/Magnesium%20citrate | Physical sciences | Citrates | Chemistry | vital_articles |
Energy engineering is a multidisciplinary field of engineering that focuses on optimizing energy systems, developing renewable energy technologies, and improving energy efficiency to meet the world's growing demand for energy in a sustainable manner. It encompasses areas such as energy harvesting and storage, energy co... | Energy engineering | Wikipedia | 421 | 9348093 | https://en.wikipedia.org/wiki/Energy%20engineering | Technology | Disciplines | null | vital_articles |
History
Human civilizations have long relied on the conversion of energy for various purposes, from the use of fire to the development of water wheels, windmills, and, eventually, electricity generation. The formalization of energy engineering began during the industrial revolution and accelerated in the mid-20th centu... | Energy engineering | Wikipedia | 419 | 9348093 | https://en.wikipedia.org/wiki/Energy%20engineering | Technology | Disciplines | null | vital_articles |
Energy efficiency is seen two ways. The first view is that more work is done from the same amount of energy used. The other perception is that the same amount of work is accomplished with less energy used in the system. Some ways to get more work out of less energy is to "Reduce, Reuse, and Recycle" the materials used ... | Energy engineering | Wikipedia | 397 | 9348093 | https://en.wikipedia.org/wiki/Energy%20engineering | Technology | Disciplines | null | vital_articles |
Education
To become an energy engineer, a bachelor's degree in energy engineering or related fields such as mechanical, electrical, or environmental engineering is typically required. Many universities now offer specialized energy engineering programs with a focus on renewable energy, energy storage, and grid managemen... | Energy engineering | Wikipedia | 364 | 9348093 | https://en.wikipedia.org/wiki/Energy%20engineering | Technology | Disciplines | null | vital_articles |
Perch is a common name for freshwater fish from the genus Perca, which belongs to the family Percidae of the large order Perciformes. The name comes from , meaning the type species of this genus, the European perch (P. fluviatilis).
Many species of freshwater game fish more or less resemble perch, but belong to differ... | Perch | Wikipedia | 148 | 47325 | https://en.wikipedia.org/wiki/Perch | Biology and health sciences | Acanthomorpha | null | vital_articles |
Species
Most authorities recognize three species within the perch genus:
The European perch (P. fluviatilis) is primarily found in Europe, but a few can also be found in South Africa, and even as far east on the Southern hemisphere as Australia. This species is typically greenish in color with dark vertical bars on it... | Perch | Wikipedia | 375 | 47325 | https://en.wikipedia.org/wiki/Perch | Biology and health sciences | Acanthomorpha | null | vital_articles |
External anatomy
Perch have a long and round body shape which allows for fast swimming in the water. True perch have "rough" or ctenoid scales. Perch have paired pectoral and pelvic fins, and two dorsal fins, the first one spiny and the second soft. These two fins can be separate or joined. The head consists of the sk... | Perch | Wikipedia | 265 | 47325 | https://en.wikipedia.org/wiki/Perch | Biology and health sciences | Acanthomorpha | null | vital_articles |
Internal anatomy
The esophagus is a flexible tube that goes from the mouth to the stomach. The stomach is connected to the intestine via the pyloric sphincter. The intestines of perch consist of the small intestine and large intestine; the intestines have many pyloric caeca and a spiral value, the small intestine cons... | Perch | Wikipedia | 441 | 47325 | https://en.wikipedia.org/wiki/Perch | Biology and health sciences | Acanthomorpha | null | vital_articles |
Fishing
Perch are a popular sport fish species. They are known to put up a fight, and to be good for eating. They can be caught with a variety of methods, including float fishing, lure fishing, and legering. Fly fishing for perch using patterns that imitate small fry or invertebrates can be successful. The record weig... | Perch | Wikipedia | 129 | 47325 | https://en.wikipedia.org/wiki/Perch | Biology and health sciences | Acanthomorpha | null | vital_articles |
Trout (: trout) is a generic common name for numerous species of carnivorous freshwater ray-finned fishes belonging to the genera Oncorhynchus, Salmo and Salvelinus, all of which are members of the subfamily Salmoninae in the family Salmonidae. The word trout is also used for some similar-shaped but non-salmonid fish, ... | Trout | Wikipedia | 496 | 47326 | https://en.wikipedia.org/wiki/Trout | Biology and health sciences | Salmoniformes | null | vital_articles |
Genus Salmo, all extant species except Atlantic salmon
Adriatic trout, Salmo obtusirostris
Brown trout, Salmo trutta
River trout, S. t. morpha fario
Lake trout/Lacustrine trout, S. t. morpha lacustris
Sea trout, S. t. morpha trutta
Flathead trout, Salmo platycephalus
Marble trout, Soca River trout or Soča trout ... | Trout | Wikipedia | 134 | 47326 | https://en.wikipedia.org/wiki/Trout | Biology and health sciences | Salmoniformes | null | vital_articles |
Genus Oncorhynchus, six of the 12 extant species
Apache trout, Oncorhynchus apache
Biwa trout, Oncorhynchus masou rhodurus
Cutthroat trout, Oncorhynchus clarki
Coastal cutthroat trout, O. c. clarki
Crescenti trout, O. c. c. f. crescenti
Alvord cutthroat trout, O. c. alvordensis (extinct)
Bonneville cutthroat tro... | Trout | Wikipedia | 511 | 47326 | https://en.wikipedia.org/wiki/Trout | Biology and health sciences | Salmoniformes | null | vital_articles |
Eagle Lake trout, Oncorhynchus mykiss aquilarum
McCloud River redband trout, Oncorhynchus mykiss stonei
Sheepheaven Creek redband trout
Mexican golden trout, Oncorhynchus chrysogaster | Trout | Wikipedia | 54 | 47326 | https://en.wikipedia.org/wiki/Trout | Biology and health sciences | Salmoniformes | null | vital_articles |
Genus Salvelinus, five of the 52 extant species
Brook trout, Salvelinus fontinalis
Aurora trout, S. f. timagamiensis
Bull trout, Salvelinus confluentus
Dolly Varden trout, Salvelinus malma
Lake trout, Salvelinus namaycush
Silver trout, † Salvelinus agassizi (extinct)
Hybrids
Tiger trout, Salmo trutta X Salvelinu... | Trout | Wikipedia | 434 | 47326 | https://en.wikipedia.org/wiki/Trout | Biology and health sciences | Salmoniformes | null | vital_articles |
There are many species, and even more populations, that are isolated from each other and morphologically different. However, since many of these distinct populations show no significant genetic differences, what may appear to be a large number of species is considered a much smaller number of distinct species by most i... | Trout | Wikipedia | 437 | 47326 | https://en.wikipedia.org/wiki/Trout | Biology and health sciences | Salmoniformes | null | vital_articles |
Trout generally feed on other fish, and soft-bodied aquatic invertebrates, such as flies, mayflies, caddisflies, stoneflies, mollusks and dragonflies. In lakes, various species of zooplankton often form a large part of the diet. In general, trout longer than about prey almost exclusively on fish, where they are availa... | Trout | Wikipedia | 407 | 47326 | https://en.wikipedia.org/wiki/Trout | Biology and health sciences | Salmoniformes | null | vital_articles |
In Mainland China, farm-raised rainbow trout from Qinghai was officially sanctioned to be labeled and sold domestically as salmon, which caused much controversy regarding food safety and consumer rights violation, as raw fish dishes or yusheng using Atlantic salmon are gaining popularity in southern China. Farmed rainb... | Trout | Wikipedia | 483 | 47326 | https://en.wikipedia.org/wiki/Trout | Biology and health sciences | Salmoniformes | null | vital_articles |
Understanding how moving water shapes the stream channel makes it easier to find trout. In most streams, the current creates a riffle-run-pool pattern that repeats itself over and over. A deep pool may hold a big brown trout, but rainbow trout and smaller brown trout are likely found in runs. Riffles are where fishers ... | Trout | Wikipedia | 455 | 47326 | https://en.wikipedia.org/wiki/Trout | Biology and health sciences | Salmoniformes | null | vital_articles |
Brook trout caught by Dr. W. Cook in the Nipigon River, Canada, on July 1, 1916, that weighed
Cutthroat trout caught by John Skimmerhorn in Pyramid Lake located in Nevada, US, on December 1, 1925, that weighed
Bull trout caught by N. Higgins in Lake Pend Oreille located in Idaho, US, on October 27, 1949, that weigh... | Trout | Wikipedia | 151 | 47326 | https://en.wikipedia.org/wiki/Trout | Biology and health sciences | Salmoniformes | null | vital_articles |
Declines in native trout populations
Salmonid populations in general have been declining due to numerous factors, including invasive species, hybridization, wildfires, and climate change. Native salmonid fish in the western and southwestern United States are threatened by non-native species that were introduced decade... | Trout | Wikipedia | 449 | 47326 | https://en.wikipedia.org/wiki/Trout | Biology and health sciences | Salmoniformes | null | vital_articles |
Climate change is also dwindling native salmonid populations. Global warming continually affects various cold-water fish such as trout, especially as inland waterbodies are more prone to warming than oceans. With an increase of temperature along with changes in spawning river flow, an abundance of trout species are eff... | Trout | Wikipedia | 115 | 47326 | https://en.wikipedia.org/wiki/Trout | Biology and health sciences | Salmoniformes | null | vital_articles |
Mackerel is a common name applied to a number of different species of pelagic fish, mostly from the family Scombridae. They are found in both temperate and tropical seas, mostly living along the coast or offshore in the oceanic environment.
Mackerel species typically have deeply forked tails and vertical "tiger-like"... | Mackerel | Wikipedia | 501 | 47332 | https://en.wikipedia.org/wiki/Mackerel | Biology and health sciences | Acanthomorpha | null | vital_articles |
The true mackerels belong to the tribe Scombrini. The tribe consists of seven species, each belonging to one of two genera: Scomber or Rastrelliger.
Scomberomorini, the Spanish mackerels
The Spanish mackerels belong to the tribe Scomberomorini, which is the "cousin tribe" of the true mackerels. This tribe consists of ... | Mackerel | Wikipedia | 382 | 47332 | https://en.wikipedia.org/wiki/Mackerel | Biology and health sciences | Acanthomorpha | null | vital_articles |
Most mackerel belong to the family Scombridae, which also includes tuna and bonito. Generally, mackerel are much smaller and slimmer than tuna, though in other respects, they share many common characteristics. Their scales, if present at all, are extremely small. Like tuna and bonito, mackerel are voracious feeders, an... | Mackerel | Wikipedia | 498 | 47332 | https://en.wikipedia.org/wiki/Mackerel | Biology and health sciences | Acanthomorpha | null | vital_articles |
Mackerel are strong swimmers. Known in the latin family as "punctualis piscis" which translates to "punctual fish." This is due to its punctuality of migration during mating season as it moves from warm to cold waters. Atlantic mackerel can swim at a sustained speed of 0.98 m/sec with a burst speed of 5.5 m/sec, while ... | Mackerel | Wikipedia | 480 | 47332 | https://en.wikipedia.org/wiki/Mackerel | Biology and health sciences | Acanthomorpha | null | vital_articles |
The remaining catch of scombroid mackerels is divided equally between the Atlantic mackerel and all other scombroid mackerels.
Just these two species (Chub mackerel and Atlantic mackerel) account for about 75% of the total catch of scombroid mackerels.
Chilean jack mackerel are the most commonly fished nonscombroid m... | Mackerel | Wikipedia | 451 | 47332 | https://en.wikipedia.org/wiki/Mackerel | Biology and health sciences | Acanthomorpha | null | vital_articles |
Mackerel preservation is not simple. Before the 19th-century development of canning and the widespread availability of refrigeration, salting and smoking were the principal preservation methods available. Historically in England, this fish was not preserved, but was consumed only in its fresh form. However, spoilage wa... | Mackerel | Wikipedia | 245 | 47332 | https://en.wikipedia.org/wiki/Mackerel | Biology and health sciences | Acanthomorpha | null | vital_articles |
Catfish (or catfishes; order Siluriformes or Nematognathi) are a diverse group of ray-finned fish. Named for their prominent barbels, which resemble a cat's whiskers, catfish range in size and behavior from the three largest species alive, the Mekong giant catfish from Southeast Asia, the wels catfish of Eurasia, and ... | Catfish | Wikipedia | 483 | 47335 | https://en.wikipedia.org/wiki/Catfish | Biology and health sciences | Siluriformes | null | vital_articles |
Catfish are believed to have a Gondwanan origin primarily centered around South America, as the most basal living catfish groups are known from there. The earliest known definitive members lived in the Americas from the Campanian to Maastrichtian stages of the Late Cretaceous, including the Andinichthyidae, Vorhisia vu... | Catfish | Wikipedia | 314 | 47335 | https://en.wikipedia.org/wiki/Catfish | Biology and health sciences | Siluriformes | null | vital_articles |
The taxonomy of catfish is quickly changing. In a 2007 and 2008 paper, Horabagrus, Phreatobius, and Conorhynchos were not classified under any current catfish families. There is disagreement on the family status of certain groups; for example, Nelson (2006) lists Auchenoglanididae and Heteropneustidae as separate famil... | Catfish | Wikipedia | 321 | 47335 | https://en.wikipedia.org/wiki/Catfish | Biology and health sciences | Siluriformes | null | vital_articles |
The higher-level phylogeny of Siluriformes has gone through several recent changes, mainly due to molecular phylogenetic studies. While most studies, both morphological and molecular, agree that catfishes are arranged into three main lineages, the relationship among these lineages has been a contentious point in which ... | Catfish | Wikipedia | 424 | 47335 | https://en.wikipedia.org/wiki/Catfish | Biology and health sciences | Siluriformes | null | vital_articles |
Unassigned families:
Bachmanniidae†
Scoloplacidae (Loricarioidei)
Akysidae (Sisoroidea)
Amblycipitidae (Sisoroidea)
Anchariidae (Arioidea)
Ariidae (Arioidea)
Amphiliidae (Big African catfishes)
Austroglanididae (Arioidea)
Chacidae (Siluroidei)
Conorhynchos (Pimelodoidea)
Cranoglanididae (Ictaluroidea)
Heter... | Catfish | Wikipedia | 477 | 47335 | https://en.wikipedia.org/wiki/Catfish | Biology and health sciences | Siluriformes | null | vital_articles |
Representatives of the genus Ictalurus have been introduced into European waters in the hope of obtaining a sporting and food resource, but the European stock of American catfishes has not achieved the dimensions of these fish in their native waters and have only increased the ecological pressure on native European fau... | Catfish | Wikipedia | 503 | 47335 | https://en.wikipedia.org/wiki/Catfish | Biology and health sciences | Siluriformes | null | vital_articles |
Catfish do not have scales; their bodies are often naked. In some species, their mucus-covered skin is used in cutaneous respiration, where the fish breathes through its skin. In some catfish, the skin is covered in bony plates called scutes; some form of body armor appears in various ways within the order. In loricari... | Catfish | Wikipedia | 509 | 47335 | https://en.wikipedia.org/wiki/Catfish | Biology and health sciences | Siluriformes | null | vital_articles |
Juvenile catfish, like most fish, have relatively large heads, eyes, and posterior median fins in comparison to larger, more mature individuals. These juveniles can be readily placed in their families, particularly those with highly derived fin or body shapes; in some cases, identification of the genus is possible. As ... | Catfish | Wikipedia | 468 | 47335 | https://en.wikipedia.org/wiki/Catfish | Biology and health sciences | Siluriformes | null | vital_articles |
These records pale in comparison to a Mekong giant catfish caught in northern Thailand on 1 May 2005, and reported to the press almost 2 months later, that weighed . This is the largest giant Mekong catfish caught since Thai officials started keeping records in 1981. Also in Asia, Jeremy Wade caught a goonch following... | Catfish | Wikipedia | 482 | 47335 | https://en.wikipedia.org/wiki/Catfish | Biology and health sciences | Siluriformes | null | vital_articles |
The occurrence of seminal vesicles, in spite of their interspecific variability in size, gross morphology, and function, has not been related to the mode of fertilization. They are typically paired, multichambered, and connected with the sperm duct, and have been reported to play glandular and storage functions. Semina... | Catfish | Wikipedia | 451 | 47335 | https://en.wikipedia.org/wiki/Catfish | Biology and health sciences | Siluriformes | null | vital_articles |
Catfish also have a sound-generating mechanism in their pectoral fins. Many species in the catfish family possess an enhanced first pectoral fin ray, called the spine, which can be moved by large abductor and adductor muscles. The base of the catfishes' spines has a sequence of ridges, and the spine normally slides wit... | Catfish | Wikipedia | 485 | 47335 | https://en.wikipedia.org/wiki/Catfish | Biology and health sciences | Siluriformes | null | vital_articles |
Catfish are easy to farm in warm climates, leading to inexpensive and safe food at local grocers. About 60% of U.S. farm-raised catfish are grown within a 65-mile (100-km) radius of Belzoni, Mississippi. Channel catfish (Ictalurus punctatus) supports a $450 million/yr aquaculture industry. The largest producers are loc... | Catfish | Wikipedia | 476 | 47335 | https://en.wikipedia.org/wiki/Catfish | Biology and health sciences | Siluriformes | null | vital_articles |
The most commonly eaten species in the United States are the channel catfish and the blue catfish, both of which are common in the wild and increasingly widely farmed. Farm-raised catfish became such a staple of the U.S. diet that President Ronald Reagan proclaimed National Catfish Day on June 25, 1987, to recognize "t... | Catfish | Wikipedia | 416 | 47335 | https://en.wikipedia.org/wiki/Catfish | Biology and health sciences | Siluriformes | null | vital_articles |
Vietnamese catfish, of the genus Pangasius, cannot be legally marketed as catfish in the United States, and so is referred to as swai or basa. Only fish of the family Ictaluridae may be marketed as catfish in the United States.See Piazza's Seafood World, LLC v. Odom , 448 F. 3d 744 (5th Cir. 2006), citing Kerrilee E. K... | Catfish | Wikipedia | 447 | 47335 | https://en.wikipedia.org/wiki/Catfish | Biology and health sciences | Siluriformes | null | vital_articles |
A fishing rod is a long, thin rod used by anglers to catch fish by manipulating a line ending in a hook (formerly known as an angle, hence the term "angling"). At its most basic form, a fishing rod is a straight rigid stick/pole with a line fastened to one end (as seen in traditional bamboo rod fishing such as Tenkara... | Fishing rod | Wikipedia | 461 | 47337 | https://en.wikipedia.org/wiki/Fishing%20rod | Technology | Hunting and fishing | null | vital_articles |
In contrast with fishing nets and traps, which are usually used in subsistence and commercial fishing, angling with rods is a far less efficient method of catching fish, and is used more often in recreational fishing and competitive casting, which focus less on the yield and more on the experience. Fishing rods also co... | Fishing rod | Wikipedia | 450 | 47337 | https://en.wikipedia.org/wiki/Fishing%20rod | Technology | Hunting and fishing | null | vital_articles |
The 18th century was mainly an era of consolidation of the techniques developed in the previous century. Running rings began to appear along the fishing rods, which gave anglers greater control over the cast line. The rods themselves were also becoming increasingly sophisticated and specialized for different roles. Joi... | Fishing rod | Wikipedia | 507 | 47337 | https://en.wikipedia.org/wiki/Fishing%20rod | Technology | Hunting and fishing | null | vital_articles |
Until the mid 19th century, rods were generally made in England. This changed in 1846 when American Samuel Phillippe introduced an imported fishing rod the first six strips of Calcutta cane made in Bavaria where Phillippe was importing Violins that he passed off as his own hand work. Split-cane rods were later independ... | Fishing rod | Wikipedia | 496 | 47337 | https://en.wikipedia.org/wiki/Fishing%20rod | Technology | Hunting and fishing | null | vital_articles |
Generally there are three types of rods used today graphite, fiberglass, and bamboo rods. Bamboo rods are the heaviest of the three, but people still use it for its feel. Fiberglass rods are the heaviest of the new chemically-made material rods. They are mostly popular with the new and young anglers, as well as anglers... | Fishing rod | Wikipedia | 480 | 47337 | https://en.wikipedia.org/wiki/Fishing%20rod | Technology | Hunting and fishing | null | vital_articles |
Power value
Also known as "rod weight", the power value of a fishing rod implies its stiffness by vaguely describing the force needed to produce a certain degree of flexure upon the rod, and may be classified as ultra-light (UL), light (L), medium-light (ML), medium (M), medium-heavy (MH), heavy (H), extra-heavy (XH), ... | Fishing rod | Wikipedia | 363 | 47337 | https://en.wikipedia.org/wiki/Fishing%20rod | Technology | Hunting and fishing | null | vital_articles |
Action
The action of a fishing rod refers to the speed with which it elastically returns to the neutral (straightened) position after a flexional load is removed (i.e. the "recoil" or "rebound" speed), and is generally described as being "slow", "medium", "fast", or anything in between (e.g. "medium-fast") or beyond (e... | Fishing rod | Wikipedia | 499 | 47337 | https://en.wikipedia.org/wiki/Fishing%20rod | Technology | Hunting and fishing | null | vital_articles |
Rod sensitivity
A rods blank will determine the amount of sensitivity anglers feel. Fishing rods made of graphite are the most sensitive due to the fact they can transfer vibrations better than rods made of fiberglass. But the rod blank is not the only thing that translates into sensitivity. The rods design will impac... | Fishing rod | Wikipedia | 457 | 47337 | https://en.wikipedia.org/wiki/Fishing%20rod | Technology | Hunting and fishing | null | vital_articles |
A rod can bend in different curves. Traditionally the bending curve is mainly determined by its tapering. In simplified terms, a fast taper will bend a lot more in the tip area and not much in the butt part, and a slow taper will tend to bend too much at the butt and delivers a weak rod. A progressive tapering which lo... | Fishing rod | Wikipedia | 466 | 47337 | https://en.wikipedia.org/wiki/Fishing%20rod | Technology | Hunting and fishing | null | vital_articles |
A common way today to describe a rod's bending properties is the Common Cents System, which is "a system of objective and relative measurement for quantifying rod power, action and even this elusive thing ... fishermen like to call feel."
The bending curve determines the way a rod builds up and releases its power. Thi... | Fishing rod | Wikipedia | 423 | 47337 | https://en.wikipedia.org/wiki/Fishing%20rod | Technology | Hunting and fishing | null | vital_articles |
Number of sections
Rods that are one piece from butt to tip are considered to have the most natural "feel" due to the theoretically uninterrupted transfer of vibrations to the angler's hand, and are preferred by many. However, the difficulty in transporting one-piece rod safely becomes an increasing problem with incre... | Fishing rod | Wikipedia | 431 | 47337 | https://en.wikipedia.org/wiki/Fishing%20rod | Technology | Hunting and fishing | null | vital_articles |
Fly rods, thin, flexible fishing rods designed to cast an artificial fly, usually consisting of a hook tied with fur, feathers, foam, or other lightweight material. More modern flies are also tied with synthetic materials. Originally made of yew, green heart, and later split bamboo (Tonkin cane), most modern fly rods a... | Fishing rod | Wikipedia | 390 | 47337 | https://en.wikipedia.org/wiki/Fishing%20rod | Technology | Hunting and fishing | null | vital_articles |
Fly rods are, in modern manufacture, almost always built out of carbon graphite. The graphite fibres are laid down in increasingly sophisticated patterns to keep the rod from flattening when stressed (usually referred to as hoop strength). The rod tapers from one end to the other and the degree of taper determines how ... | Fishing rod | Wikipedia | 212 | 47337 | https://en.wikipedia.org/wiki/Fishing%20rod | Technology | Hunting and fishing | null | vital_articles |
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