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Phages were discovered to be antibacterial agents and were used in the former Soviet Republic of Georgia (pioneered there by Giorgi Eliava with help from the co-discoverer of bacteriophages, Félix d'Hérelle) during the 1920s and 1930s for treating bacterial infections.
D'Herelle "quickly learned that bacteriophages a... | Bacteriophage | Wikipedia | 221 | 4185 | https://en.wikipedia.org/wiki/Bacteriophage | Biology and health sciences | Biology basics | Biology |
The use of phages has continued since the end of the Cold War in Russia, Georgia, and elsewhere in Central and Eastern Europe. The first regulated, randomized, double-blind clinical trial was reported in the Journal of Wound Care in June 2009, which evaluated the safety and efficacy of a bacteriophage cocktail to treat... | Bacteriophage | Wikipedia | 465 | 4185 | https://en.wikipedia.org/wiki/Bacteriophage | Biology and health sciences | Biology basics | Biology |
In 2017, a 68-year-old diabetic patient with necrotizing pancreatitis complicated by a pseudocyst infected with MDR A. baumannii strains was being treated with a cocktail of Azithromycin, Rifampicin, and Colistin for 4 months without results and overall rapidly declining health.
Because discussion had begun of the c... | Bacteriophage | Wikipedia | 461 | 4185 | https://en.wikipedia.org/wiki/Bacteriophage | Biology and health sciences | Biology basics | Biology |
Food industry
Phages have increasingly been used to safen food products and to forestall spoilage bacteria. Since 2006, the United States Food and Drug Administration (FDA) and United States Department of Agriculture (USDA) have approved several bacteriophage products. LMP-102 (Intralytix) was approved for treating rea... | Bacteriophage | Wikipedia | 476 | 4185 | https://en.wikipedia.org/wiki/Bacteriophage | Biology and health sciences | Biology basics | Biology |
Counteracting bioweapons and toxins
Government agencies in the West have for several years been looking to Georgia and the former Soviet Union for help with exploiting phages for counteracting bioweapons and toxins, such as anthrax and botulism. Developments are continuing among research groups in the U.S. Other uses i... | Bacteriophage | Wikipedia | 461 | 4185 | https://en.wikipedia.org/wiki/Bacteriophage | Biology and health sciences | Biology basics | Biology |
Dairy industry
Bacteriophages present in the environment can cause cheese to not ferment. In order to avoid this, mixed-strain starter cultures and culture rotation regimes can be used. Genetic engineering of culture microbes – especially Lactococcus lactis and Streptococcus thermophilus – have been studied for genetic... | Bacteriophage | Wikipedia | 501 | 4185 | https://en.wikipedia.org/wiki/Bacteriophage | Biology and health sciences | Biology basics | Biology |
Sometimes prophages may provide benefits to the host bacterium while they are dormant by adding new functions to the bacterial genome, in a phenomenon called lysogenic conversion. Examples are the conversion of harmless strains of Corynebacterium diphtheriae or Vibrio cholerae by bacteriophages to highly virulent ones ... | Bacteriophage | Wikipedia | 372 | 4185 | https://en.wikipedia.org/wiki/Bacteriophage | Biology and health sciences | Biology basics | Biology |
Synthesis of proteins and nucleic acid
Within minutes, bacterial ribosomes start translating viral mRNA into protein. For RNA-based phages, RNA replicase is synthesized early in the process. Proteins modify the bacterial RNA polymerase so it preferentially transcribes viral mRNA. The host's normal synthesis of protein... | Bacteriophage | Wikipedia | 485 | 4185 | https://en.wikipedia.org/wiki/Bacteriophage | Biology and health sciences | Biology basics | Biology |
Release of virions
Phages may be released via cell lysis, by extrusion, or, in a few cases, by budding. Lysis, by tailed phages, is achieved by an enzyme called endolysin, which attacks and breaks down the cell wall peptidoglycan. An altogether different phage type, the filamentous phage, makes the host cell continual... | Bacteriophage | Wikipedia | 215 | 4185 | https://en.wikipedia.org/wiki/Bacteriophage | Biology and health sciences | Biology basics | Biology |
Genome structure
Given the millions of different phages in the environment, phage genomes come in a variety of forms and sizes. RNA phages such as MS2 have the smallest genomes, with only a few kilobases. However, some DNA phages such as T4 may have large genomes with hundreds of genes; the size and shape of the capsi... | Bacteriophage | Wikipedia | 499 | 4185 | https://en.wikipedia.org/wiki/Bacteriophage | Biology and health sciences | Biology basics | Biology |
For instance, infection of Pseudomonas aeruginosa by the temperate phage PaP3 changed the expression of 38% (2160/5633) of its host's genes. Many of these effects are probably indirect, hence the challenge becomes to identify the direct interactions among bacteria and phage.
Several attempts have been made to map prot... | Bacteriophage | Wikipedia | 484 | 4185 | https://en.wikipedia.org/wiki/Bacteriophage | Biology and health sciences | Biology basics | Biology |
Bacteriophages are thought to contribute extensively to horizontal gene transfer in natural environments, principally via transduction, but also via transformation. Metagenomics-based studies also have revealed that viromes from a variety of environments harbor antibiotic-resistance genes, including those that could co... | Bacteriophage | Wikipedia | 432 | 4185 | https://en.wikipedia.org/wiki/Bacteriophage | Biology and health sciences | Biology basics | Biology |
186 phage
λ phage
Φ6 phage
Φ29 phage
ΦX174
Bacteriophage φCb5
G4 phage
M13 phage
MS2 phage (23–28 nm in size)
N4 phage
P1 phage
P2 phage
P4 phage
R17 phage
T2 phage
T4 phage (169 kbp genome, 200 nm long)
T7 phage
T12 phage
Bacteriophage databases and resources
Phagesdb
Phagescope | Bacteriophage | Wikipedia | 106 | 4185 | https://en.wikipedia.org/wiki/Bacteriophage | Biology and health sciences | Biology basics | Biology |
Bohrium is a synthetic chemical element; it has symbol Bh and atomic number 107. It is named after Danish physicist Niels Bohr. As a synthetic element, it can be created in particle accelerators but is not found in nature. All known isotopes of bohrium are highly radioactive; the most stable known isotope is 270Bh with... | Bohrium | Wikipedia | 464 | 4194 | https://en.wikipedia.org/wiki/Bohrium | Physical sciences | Group 7 | Chemistry |
In 1981, a German research team led by Peter Armbruster and Gottfried Münzenberg at the GSI Helmholtz Centre for Heavy Ion Research (GSI Helmholtzzentrum für Schwerionenforschung) in Darmstadt bombarded a target of bismuth-209 with accelerated nuclei of chromium-54 to produce 5 atoms of the isotope bohrium-262:
+ → ... | Bohrium | Wikipedia | 480 | 4194 | https://en.wikipedia.org/wiki/Bohrium | Physical sciences | Group 7 | Chemistry |
Bohrium has no stable or naturally occurring isotopes. Several radioactive isotopes have been synthesized in the laboratory, either by fusing two atoms or by observing the decay of heavier elements. Twelve different isotopes of bohrium have been reported with atomic masses 260–262, 264–267, 270–272, 274, and 278, one o... | Bohrium | Wikipedia | 499 | 4194 | https://en.wikipedia.org/wiki/Bohrium | Physical sciences | Group 7 | Chemistry |
Chemical
Bohrium is the fifth member of the 6d series of transition metals and the heaviest member of group 7 in the periodic table, below manganese, technetium and rhenium. All the members of the group readily portray their group oxidation state of +7 and the state becomes more stable as the group is descended. Thus b... | Bohrium | Wikipedia | 509 | 4194 | https://en.wikipedia.org/wiki/Bohrium | Physical sciences | Group 7 | Chemistry |
Physical and atomic
Bohrium is expected to be a solid under normal conditions and assume a hexagonal close-packed crystal structure (c/a = 1.62), similar to its lighter congener rhenium. Early predictions by Fricke estimated its density at 37.1 g/cm3, but newer calculations predict a somewhat lower value of 26–27 g/cm3... | Bohrium | Wikipedia | 442 | 4194 | https://en.wikipedia.org/wiki/Bohrium | Physical sciences | Group 7 | Chemistry |
In 2000, it was confirmed that although relativistic effects are important, bohrium behaves like a typical group 7 element. A team at the Paul Scherrer Institute (PSI) conducted a chemistry reaction using six atoms of 267Bh produced in the reaction between 249Bk and 22Ne ions. The resulting atoms were thermalised and r... | Bohrium | Wikipedia | 333 | 4194 | https://en.wikipedia.org/wiki/Bohrium | Physical sciences | Group 7 | Chemistry |
Barnard's Star is a small red dwarf star in the constellation of Ophiuchus. At a distance of from Earth, it is the fourth-nearest-known individual star to the Sun after the three components of the Alpha Centauri system, and is the closest star in the northern celestial hemisphere. Its stellar mass is about 16% of the ... | Barnard's Star | Wikipedia | 406 | 4196 | https://en.wikipedia.org/wiki/Barnard%27s%20Star | Physical sciences | Notable stars | Astronomy |
At 7–12 billion years of age, Barnard's Star is considerably older than the Sun, which is 4.5 billion years old, and it might be among the oldest stars in the Milky Way galaxy. Barnard's Star has lost a great deal of rotational energy; the periodic slight changes in its brightness indicate that it rotates once in 130 d... | Barnard's Star | Wikipedia | 466 | 4196 | https://en.wikipedia.org/wiki/Barnard%27s%20Star | Physical sciences | Notable stars | Astronomy |
Barnard's Star has a mass of about 0.16 solar masses (), and a radius about 0.2 times that of the Sun. Thus, although Barnard's Star has roughly 150 times the mass of Jupiter (), its radius is only roughly 2 times larger, due to its much higher density. Its effective temperature is about 3,220 kelvin, and it has a lumi... | Barnard's Star | Wikipedia | 439 | 4196 | https://en.wikipedia.org/wiki/Barnard%27s%20Star | Physical sciences | Notable stars | Astronomy |
Previous planetary claims
Barnard's Star has been subject to multiple claims of planets that were later disproven. From the early 1960s to the early 1970s, Peter van de Kamp argued that planets orbited Barnard's Star. His specific claims of large gas giants were refuted in the mid-1970s after much debate. In November ... | Barnard's Star | Wikipedia | 452 | 4196 | https://en.wikipedia.org/wiki/Barnard%27s%20Star | Physical sciences | Notable stars | Astronomy |
Van de Kamp never acknowledged any error and published a further claim of two planets' existence as late as 1982; he died in 1995. Wulff Heintz, Van de Kamp's successor at Swarthmore and an expert on double stars, questioned his findings and began publishing criticisms from 1976 onwards. The two men were reported to ha... | Barnard's Star | Wikipedia | 408 | 4196 | https://en.wikipedia.org/wiki/Barnard%27s%20Star | Physical sciences | Notable stars | Astronomy |
Null results for planetary companions continued throughout the 1980s and 1990s, including interferometric work with the Hubble Space Telescope in 1999. Gatewood was able to show in 1995 that planets with were impossible around Barnard's Star, in a paper which helped refine the negative certainty regarding planetary ob... | Barnard's Star | Wikipedia | 413 | 4196 | https://en.wikipedia.org/wiki/Barnard%27s%20Star | Physical sciences | Notable stars | Astronomy |
The analysis of radial velocities that eventually led to the announcement of a candidate super-Earth orbiting Barnard's Star was also used to set more precise upper mass limits for possible planets, up to and within the habitable zone: a maximum of up to the inner edge and on the outer edge of the optimistic habitabl... | Barnard's Star | Wikipedia | 475 | 4196 | https://en.wikipedia.org/wiki/Barnard%27s%20Star | Physical sciences | Notable stars | Astronomy |
2019
In 2019, two additional ultraviolet stellar flares were detected, each with far-ultraviolet energy of 3×1022 joules, together with one X-ray stellar flare with energy 1.6×1022 joules. The flare rate observed to date is enough to cause loss of 87 Earth atmospheres per billion years through thermal processes and ≈3 ... | Barnard's Star | Wikipedia | 419 | 4196 | https://en.wikipedia.org/wiki/Barnard%27s%20Star | Physical sciences | Notable stars | Astronomy |
The initial Project Daedalus model sparked further theoretical research. In 1980, Robert Freitas suggested a more ambitious plan: a self-replicating spacecraft intended to search for and make contact with extraterrestrial life. Built and launched in Jupiter's orbit, it would reach Barnard's Star in 47 years under param... | Barnard's Star | Wikipedia | 119 | 4196 | https://en.wikipedia.org/wiki/Barnard%27s%20Star | Physical sciences | Notable stars | Astronomy |
Boötes ( ) is a constellation in the northern sky, located between 0° and +60° declination, and 13 and 16 hours of right ascension on the celestial sphere. The name comes from , which comes from 'herdsman' or 'plowman' (literally, 'ox-driver'; from boûs 'cow').
One of the 48 constellations described by the 2nd-centu... | Boötes | Wikipedia | 400 | 4200 | https://en.wikipedia.org/wiki/Bo%C3%B6tes | Physical sciences | Other | Astronomy |
Another myth associated with Boötes by Hyginus is that of Icarius, who was schooled as a grape farmer and winemaker by Dionysus. Icarius made wine so strong that those who drank it appeared poisoned, which caused shepherds to avenge their supposedly poisoned friends by killing Icarius. Maera, Icarius' dog, brought his ... | Boötes | Wikipedia | 407 | 4200 | https://en.wikipedia.org/wiki/Bo%C3%B6tes | Physical sciences | Other | Astronomy |
Several former constellations were formed from stars now included in Boötes. Quadrans Muralis, the Quadrant, was a constellation created near Beta Boötis from faint stars. It was designated in 1795 by Jérôme Lalande, an astronomer who used a quadrant to perform detailed astronometric measurements. Lalande worked with N... | Boötes | Wikipedia | 469 | 4200 | https://en.wikipedia.org/wiki/Bo%C3%B6tes | Physical sciences | Other | Astronomy |
The other Chinese constellations made up of the stars of Boötes existed in the modern constellation's north; they are all representations of weapons. Tianqiang, the spear, was formed from Iota, Kappa and Theta Boötis; Genghe, variously representing a lance or shield, was formed from Epsilon, Rho and Sigma Boötis.
Ther... | Boötes | Wikipedia | 445 | 4200 | https://en.wikipedia.org/wiki/Bo%C3%B6tes | Physical sciences | Other | Astronomy |
Colloquially, its pattern of stars has been likened to a kite or ice cream cone. However, depictions of Boötes have varied historically. Aratus described him circling the north pole, herding the two bears. Later ancient Greek depictions, described by Ptolemy, have him holding the reins of his hunting dogs (Canes Venati... | Boötes | Wikipedia | 434 | 4200 | https://en.wikipedia.org/wiki/Bo%C3%B6tes | Physical sciences | Other | Astronomy |
Bayer located Arcturus above the Herdman's left knee in his Uranometria. Nearby Eta Boötis, or Muphrid, is the uppermost star denoting the left leg. It is a 2.68-magnitude star 37 light-years distant with a spectral class of G0IV, indicating it has just exhausted its core hydrogen and is beginning to expand and cool. I... | Boötes | Wikipedia | 465 | 4200 | https://en.wikipedia.org/wiki/Bo%C3%B6tes | Physical sciences | Other | Astronomy |
Mu Boötis, known as Alkalurops, is a triple star popular with amateur astronomers. It has an overall magnitude of 4.3 and is 121 light-years away. Its name is from the Arabic phrase for "club" or "staff". The primary appears to be of magnitude 4.3 and is blue-white. The secondary appears to be of magnitude 6.5, but is ... | Boötes | Wikipedia | 427 | 4200 | https://en.wikipedia.org/wiki/Bo%C3%B6tes | Physical sciences | Other | Astronomy |
Nearby Rho and Sigma Boötis denote the herdsman's waist. Rho is an orange giant of spectral type K3III located around 160 light-years from Earth. It is ever so slightly variable, wavering by 0.003 of a magnitude from its average of 3.57. Sigma, a yellow-white main-sequence star of spectral type F3V, is suspected of var... | Boötes | Wikipedia | 395 | 4200 | https://en.wikipedia.org/wiki/Bo%C3%B6tes | Physical sciences | Other | Astronomy |
An apparent magnitude 4.18 type A0p star, Lambda Boötis is the prototype of a class of chemically peculiar stars, only some of which pulsate as Delta Scuti-type stars. The distinction between the Lambda Boötis stars as a class of stars with peculiar spectra, and the Delta Scuti stars whose class describes pulsation in ... | Boötes | Wikipedia | 468 | 4200 | https://en.wikipedia.org/wiki/Bo%C3%B6tes | Physical sciences | Other | Astronomy |
There is one bright B-class star in Boötes; magnitude 4.93 Pi1 Boötis, also called Alazal. It has a spectral class of B9 and is 40 parsecs from Earth. There is also one M-type star, magnitude 4.81 34 Boötis. It is of class gM0.
Multiple stars
Besides Pulcherrima and Alkalurops, there are several other binary stars i... | Boötes | Wikipedia | 446 | 4200 | https://en.wikipedia.org/wiki/Bo%C3%B6tes | Physical sciences | Other | Astronomy |
44 Boötis (i Boötis) is a double variable star 42 light-years away. It has an overall magnitude of 4.8 and appears yellow to the naked eye. The primary is of magnitude 5.3 and the secondary is of magnitude 6.1; their orbital period is 220 years. The secondary is itself an eclipsing variable star with a range of 0.6 mag... | Boötes | Wikipedia | 479 | 4200 | https://en.wikipedia.org/wiki/Bo%C3%B6tes | Physical sciences | Other | Astronomy |
Extrasolar planets have been discovered encircling ten stars in Boötes as of 2012. Tau Boötis is orbited by a large planet, discovered in 1999. The host star itself is a magnitude 4.5 star of type F7V, 15.6 parsecs from Earth. It has a mass of and a radius of 1.331 solar radii (); a companion, GJ527B, orbits at a dist... | Boötes | Wikipedia | 451 | 4200 | https://en.wikipedia.org/wiki/Bo%C3%B6tes | Physical sciences | Other | Astronomy |
The larger of the two, HD 128311 c, has a mass of and was discovered in the same manner. It orbits every 919 days inclined at 50°, and is 1.76 AU from the host star. The host star, HD 128311, is a K0V-type star located 16.6 parsecs from Earth. It is smaller than the Sun, with a mass of and a radius of ; it also appea... | Boötes | Wikipedia | 427 | 4200 | https://en.wikipedia.org/wiki/Bo%C3%B6tes | Physical sciences | Other | Astronomy |
Another single planetary system in Boötes is the HD 132563 system, a triple star system. The parent star, technically HD 132563B, is a star of magnitude 9.47, 96 parsecs from Earth. It is almost exactly the size of the Sun, with the same radius and a mass only 1% greater. Its planet, HD 132563B b, was discovered in 201... | Boötes | Wikipedia | 390 | 4200 | https://en.wikipedia.org/wiki/Bo%C3%B6tes | Physical sciences | Other | Astronomy |
Boötes is in a part of the celestial sphere facing away from the plane of our home Milky Way galaxy, and so does not have open clusters or nebulae. Instead, it has one bright globular cluster and many faint galaxies. The globular cluster NGC 5466 has an overall magnitude of 9.1 and a diameter of 11 arcminutes. It is a ... | Boötes | Wikipedia | 504 | 4200 | https://en.wikipedia.org/wiki/Bo%C3%B6tes | Physical sciences | Other | Astronomy |
Boötes is home to the Quadrantid meteor shower, the most prolific annual meteor shower. It was discovered in January 1835 and named in 1864 by Alexander Herschel. The radiant is located in northern Boötes near Kappa Boötis, in its namesake former constellation of Quadrans Muralis. Quadrantid meteors are dim, but have a... | Boötes | Wikipedia | 419 | 4200 | https://en.wikipedia.org/wiki/Bo%C3%B6tes | Physical sciences | Other | Astronomy |
The June Bootids, also known as the Iota Draconids, is a meteor shower associated with the comet 7P/Pons–Winnecke, first recognized on May 27, 1916, by William F. Denning. The shower, with its slow meteors, was not observed prior to 1916 because Earth did not cross the comet's dust trail until Jupiter perturbed Pons–Wi... | Boötes | Wikipedia | 472 | 4200 | https://en.wikipedia.org/wiki/Bo%C3%B6tes | Physical sciences | Other | Astronomy |
The Beta Bootids is a weak shower that begins on January 5, peaks on January 16, and ends on January 18. Its meteors travel at 43 km/s. The January Bootids is a short, young meteor shower that begins on January 9, peaks from January 16 to January 18, and ends on January 18.
The Phi Bootids is another weak shower radia... | Boötes | Wikipedia | 467 | 4200 | https://en.wikipedia.org/wiki/Bo%C3%B6tes | Physical sciences | Other | Astronomy |
Bipedalism is a form of terrestrial locomotion where an animal moves by means of its two rear (or lower) limbs or legs. An animal or machine that usually moves in a bipedal manner is known as a biped , meaning 'two feet' (from Latin bis 'double' and pes 'foot'). Types of bipedal movement include walking or running (a b... | Bipedalism | Wikipedia | 426 | 4210 | https://en.wikipedia.org/wiki/Bipedalism | Biology and health sciences | Ethology | null |
Advantages
Limited and exclusive bipedalism can offer a species several advantages. Bipedalism raises the head; this allows a greater field of vision with improved detection of distant dangers or resources, access to deeper water for wading animals and allows the animals to reach higher food sources with their mouths. ... | Bipedalism | Wikipedia | 463 | 4210 | https://en.wikipedia.org/wiki/Bipedalism | Biology and health sciences | Ethology | null |
Movement
There are a number of states of movement commonly associated with bipedalism.
Standing. Staying still on both legs. In most bipeds this is an active process, requiring constant adjustment of balance.
Walking. One foot in front of another, with at least one foot on the ground at any time.
Running. One foot in f... | Bipedalism | Wikipedia | 409 | 4210 | https://en.wikipedia.org/wiki/Bipedalism | Biology and health sciences | Ethology | null |
Dinosaurs diverged from their archosaur ancestors approximately 230 million years ago during the Middle to Late Triassic period, roughly 20 million years after the Permian-Triassic extinction event wiped out an estimated 95 percent of all life on Earth. Radiometric dating of fossils from the early dinosaur genus Eorapt... | Bipedalism | Wikipedia | 370 | 4210 | https://en.wikipedia.org/wiki/Bipedalism | Biology and health sciences | Ethology | null |
Bipedal movement is less common among mammals, most of which are quadrupedal. All primates possess some bipedal ability, though most species primarily use quadrupedal locomotion on land. Primates aside, the macropods (kangaroos, wallabies and their relatives), kangaroo rats and mice, hopping mice and springhare move bi... | Bipedalism | Wikipedia | 498 | 4210 | https://en.wikipedia.org/wiki/Bipedalism | Biology and health sciences | Ethology | null |
Injured individuals
Injured chimpanzees and bonobos have been capable of sustained bipedalism.
Three captive primates, one macaque Natasha and two chimps, Oliver and Poko (chimpanzee), were found to move bipedally. Natasha switched to exclusive bipedalism after an illness, while Poko was discovered in captivity in a t... | Bipedalism | Wikipedia | 376 | 4210 | https://en.wikipedia.org/wiki/Bipedalism | Biology and health sciences | Ethology | null |
Limited bipedalism in non-mammals (and non-birds)
Bipedalism is unknown among the amphibians. Among the non-archosaur reptiles bipedalism is rare, but it is found in the "reared-up" running of lizards such as agamids and monitor lizards. Many reptile species will also temporarily adopt bipedalism while fighting. One ge... | Bipedalism | Wikipedia | 181 | 4210 | https://en.wikipedia.org/wiki/Bipedalism | Biology and health sciences | Ethology | null |
There are at least twelve distinct hypotheses as to how and why bipedalism evolved in humans, and also some debate as to when. Bipedalism evolved well before the large human brain or the development of stone tools. Bipedal specializations are found in Australopithecus fossils from 4.2 to 3.9 million years ago and recen... | Bipedalism | Wikipedia | 348 | 4210 | https://en.wikipedia.org/wiki/Bipedalism | Biology and health sciences | Ethology | null |
The form and function of modern-day humans' upper bodies appear to have evolved from living in a more forested setting. Living in this kind of environment would have made it so that being able to travel arboreally would have been advantageous at the time. Although different to human walking, bipedal locomotion in trees... | Bipedalism | Wikipedia | 301 | 4210 | https://en.wikipedia.org/wiki/Bipedalism | Biology and health sciences | Ethology | null |
Multiple factors
Napier (1963) argued that it is unlikely that a single factor drove the evolution of bipedalism. He stated "It seems unlikely that any single factor was responsible for such a dramatic change in behaviour. In addition to the advantages of accruing from ability to carry objects – food or otherwise – the... | Bipedalism | Wikipedia | 243 | 4210 | https://en.wikipedia.org/wiki/Bipedalism | Biology and health sciences | Ethology | null |
According to the Savanna-based theory, hominines came down from the tree's branches and adapted to life on the savanna by walking erect on two feet. The theory suggests that early hominids were forced to adapt to bipedal locomotion on the open savanna after they left the trees. One of the proposed mechanisms was the kn... | Bipedalism | Wikipedia | 333 | 4210 | https://en.wikipedia.org/wiki/Bipedalism | Biology and health sciences | Ethology | null |
Others state hominines had already achieved the bipedal adaptation that was used in the savanna. The fossil evidence reveals that early bipedal hominins were still adapted to climbing trees at the time they were also walking upright. It is possible that bipedalism evolved in the trees, and was later applied to the sava... | Bipedalism | Wikipedia | 451 | 4210 | https://en.wikipedia.org/wiki/Bipedalism | Biology and health sciences | Ethology | null |
Traveling efficiency hypothesis
An alternative explanation is that the mixture of savanna and scattered forests increased terrestrial travel by proto-humans between clusters of trees, and bipedalism offered greater efficiency for long-distance travel between these clusters than quadrupedalism. In an experiment monitori... | Bipedalism | Wikipedia | 356 | 4210 | https://en.wikipedia.org/wiki/Bipedalism | Biology and health sciences | Ethology | null |
A related study conducted by University of Birmingham, Professor Susannah Thorpe examined the most arboreal great ape, the orangutan, holding onto supporting branches in order to navigate branches that were too flexible or unstable otherwise. In more than 75 percent of observations, the orangutans used their forelimbs ... | Bipedalism | Wikipedia | 475 | 4210 | https://en.wikipedia.org/wiki/Bipedalism | Biology and health sciences | Ethology | null |
However, this model has been debated, as others have argued that early bipedal hominids were instead polygynous. Among most monogamous primates, males and females are about the same size. That is sexual dimorphism is minimal, and other studies have suggested that Australopithecus afarensis males were nearly twice the w... | Bipedalism | Wikipedia | 282 | 4210 | https://en.wikipedia.org/wiki/Bipedalism | Biology and health sciences | Ethology | null |
Early bipedalism in homininae model
Recent studies of 4.4 million years old Ardipithecus ramidus suggest bipedalism. It is thus possible that bipedalism evolved very early in homininae and was reduced in chimpanzee and gorilla when they became more specialized. Other recent studies of the foot structure of Ardipithecus... | Bipedalism | Wikipedia | 476 | 4210 | https://en.wikipedia.org/wiki/Bipedalism | Biology and health sciences | Ethology | null |
Other behavioural models
There are a variety of ideas which promote a specific change in behaviour as the key driver for the evolution of hominid bipedalism. For example, Wescott (1967) and later Jablonski & Chaplin (1993) suggest that bipedal threat displays could have been the transitional behaviour which led to some... | Bipedalism | Wikipedia | 462 | 4210 | https://en.wikipedia.org/wiki/Bipedalism | Biology and health sciences | Ethology | null |
Carrying models
Charles Darwin wrote that "Man could not have attained his present dominant position in the world without the use of his hands, which are so admirably adapted to the act of obedience of his will". Darwin (1871:52) and many models on bipedal origins are based on this line of thought. Gordon Hewes (1961) ... | Bipedalism | Wikipedia | 237 | 4210 | https://en.wikipedia.org/wiki/Bipedalism | Biology and health sciences | Ethology | null |
Wading models
The observation that large primates, including especially the great apes, that predominantly move quadrupedally on dry land, tend to switch to bipedal locomotion in waist deep water, has led to the idea that the origin of human bipedalism may have been influenced by waterside environments. This idea, lab... | Bipedalism | Wikipedia | 447 | 4210 | https://en.wikipedia.org/wiki/Bipedalism | Biology and health sciences | Ethology | null |
Non-human primates habitually deliver their young on their own, but the same cannot be said for modern-day humans. Isolated birth appears to be rare and actively avoided cross-culturally, even if birthing methods may differ between said cultures. This is due to the fact that the narrowing of the hips and the change in ... | Bipedalism | Wikipedia | 475 | 4210 | https://en.wikipedia.org/wiki/Bipedalism | Biology and health sciences | Ethology | null |
In humans, walking is composed of several separate processes:
Vaulting over a stiff stance leg
Passive ballistic movement of the swing leg
A short 'push' from the ankle prior to toe-off, propelling the swing leg
Rotation of the hips about the axis of the spine, to increase stride length
Rotation of the hips about the h... | Bipedalism | Wikipedia | 384 | 4210 | https://en.wikipedia.org/wiki/Bipedalism | Biology and health sciences | Ethology | null |
Quadrupeds, have more restrictive breathing respire while moving than do bipedal humans. "Quadrupedal species normally synchronize the locomotor and respiratory cycles at a constant ratio of 1:1 (strides per breath) in both the trot and gallop. Human runners differ from quadrupeds in that while running they employ seve... | Bipedalism | Wikipedia | 427 | 4210 | https://en.wikipedia.org/wiki/Bipedalism | Biology and health sciences | Ethology | null |
Bioinformatics () is an interdisciplinary field of science that develops methods and software tools for understanding biological data, especially when the data sets are large and complex. Bioinformatics uses biology, chemistry, physics, computer science, data science, computer programming, information engineering, math... | Bioinformatics | Wikipedia | 506 | 4214 | https://en.wikipedia.org/wiki/Bioinformatics | Biology and health sciences | Biology basics | Biology |
Analyzing biological data to produce meaningful information involves writing and running software programs that use algorithms from graph theory, artificial intelligence, soft computing, data mining, image processing, and computer simulation. The algorithms in turn depend on theoretical foundations such as discrete mat... | Bioinformatics | Wikipedia | 474 | 4214 | https://en.wikipedia.org/wiki/Bioinformatics | Biology and health sciences | Biology basics | Biology |
The primary goal of bioinformatics is to increase the understanding of biological processes. What sets it apart from other approaches is its focus on developing and applying computationally intensive techniques to achieve this goal. Examples include: pattern recognition, data mining, machine learning algorithms, and vi... | Bioinformatics | Wikipedia | 462 | 4214 | https://en.wikipedia.org/wiki/Bioinformatics | Biology and health sciences | Biology basics | Biology |
Most DNA sequencing techniques produce short fragments of sequence that need to be assembled to obtain complete gene or genome sequences. The shotgun sequencing technique (used by The Institute for Genomic Research (TIGR) to sequence the first bacterial genome, Haemophilus influenzae) generates the sequences of many th... | Bioinformatics | Wikipedia | 454 | 4214 | https://en.wikipedia.org/wiki/Bioinformatics | Biology and health sciences | Biology basics | Biology |
Understanding the function of genes and their products in the context of cellular and organismal physiology is the goal of process-level annotation. An obstacle of process-level annotation has been the inconsistency of terms used by different model systems. The Gene Ontology Consortium is helping to solve this problem.... | Bioinformatics | Wikipedia | 380 | 4214 | https://en.wikipedia.org/wiki/Bioinformatics | Biology and health sciences | Biology basics | Biology |
Evolutionary biology is the study of the origin and descent of species, as well as their change over time. Informatics has assisted evolutionary biologists by enabling researchers to:
trace the evolution of a large number of organisms by measuring changes in their DNA, rather than through physical taxonomy or physiolo... | Bioinformatics | Wikipedia | 376 | 4214 | https://en.wikipedia.org/wiki/Bioinformatics | Biology and health sciences | Biology basics | Biology |
Pan genomics is a concept introduced in 2005 by Tettelin and Medini. Pan genome is the complete gene repertoire of a particular monophyletic taxonomic group. Although initially applied to closely related strains of a species, it can be applied to a larger context like genus, phylum, etc. It is divided in two parts: the... | Bioinformatics | Wikipedia | 488 | 4214 | https://en.wikipedia.org/wiki/Bioinformatics | Biology and health sciences | Biology basics | Biology |
In cancer, the genomes of affected cells are rearranged in complex or unpredictable ways. In addition to single-nucleotide polymorphism arrays identifying point mutations that cause cancer, oligonucleotide microarrays can be used to identify chromosomal gains and losses (called comparative genomic hybridization). These... | Bioinformatics | Wikipedia | 426 | 4214 | https://en.wikipedia.org/wiki/Bioinformatics | Biology and health sciences | Biology basics | Biology |
Analysis of protein expression
Protein microarrays and high throughput (HT) mass spectrometry (MS) can provide a snapshot of the proteins present in a biological sample. The former approach faces similar problems as with microarrays targeted at mRNA, the latter involves the problem of matching large amounts of mass dat... | Bioinformatics | Wikipedia | 505 | 4214 | https://en.wikipedia.org/wiki/Bioinformatics | Biology and health sciences | Biology basics | Biology |
Protein localization
Finding the location of proteins allows us to predict what they do. This is called protein function prediction. For instance, if a protein is found in the nucleus it may be involved in gene regulation or splicing. By contrast, if a protein is found in mitochondria, it may be involved in respiration... | Bioinformatics | Wikipedia | 491 | 4214 | https://en.wikipedia.org/wiki/Bioinformatics | Biology and health sciences | Biology basics | Biology |
One example of this is hemoglobin in humans and the hemoglobin in legumes (leghemoglobin), which are distant relatives from the same protein superfamily. Both serve the same purpose of transporting oxygen in the organism. Although both of these proteins have completely different amino acid sequences, their protein stru... | Bioinformatics | Wikipedia | 476 | 4214 | https://en.wikipedia.org/wiki/Bioinformatics | Biology and health sciences | Biology basics | Biology |
Other interactions encountered in the field include Protein–ligand (including drug) and protein–peptide. Molecular dynamic simulation of movement of atoms about rotatable bonds is the fundamental principle behind computational algorithms, termed docking algorithms, for studying molecular interactions.
Biodiversity inf... | Bioinformatics | Wikipedia | 475 | 4214 | https://en.wikipedia.org/wiki/Bioinformatics | Biology and health sciences | Biology basics | Biology |
Ontologies and data integration
Biological ontologies are directed acyclic graphs of controlled vocabularies. They create categories for biological concepts and descriptions so they can be easily analyzed with computers. When categorised in this way, it is possible to gain added value from holistic and integrated analy... | Bioinformatics | Wikipedia | 468 | 4214 | https://en.wikipedia.org/wiki/Bioinformatics | Biology and health sciences | Biology basics | Biology |
Open-source bioinformatics software includes Bioconductor, BioPerl, Biopython, BioJava, BioJS, BioRuby, Bioclipse, EMBOSS, .NET Bio, Orange with its bioinformatics add-on, Apache Taverna, UGENE and GenoCAD.
The non-profit Open Bioinformatics Foundation and the annual Bioinformatics Open Source Conference promote open-... | Bioinformatics | Wikipedia | 432 | 4214 | https://en.wikipedia.org/wiki/Bioinformatics | Biology and health sciences | Biology basics | Biology |
BioCompute and BioCompute Objects
In 2014, the US Food and Drug Administration sponsored a conference held at the National Institutes of Health Bethesda Campus to discuss reproducibility in bioinformatics. Over the next three years, a consortium of stakeholders met regularly to discuss what would become BioCompute par... | Bioinformatics | Wikipedia | 498 | 4214 | https://en.wikipedia.org/wiki/Bioinformatics | Biology and health sciences | Biology basics | Biology |
MOOC platforms also provide online certifications in bioinformatics and related disciplines, including Coursera's Bioinformatics Specialization at the University of California, San Diego, Genomic Data Science Specialization at Johns Hopkins University, and EdX's Data Analysis for Life Sciences XSeries at Harvard Univer... | Bioinformatics | Wikipedia | 117 | 4214 | https://en.wikipedia.org/wiki/Bioinformatics | Biology and health sciences | Biology basics | Biology |
The cell is the basic structural and functional unit of all forms of life. Every cell consists of cytoplasm enclosed within a membrane; many cells contain organelles, each with a specific function. The term comes from the Latin word meaning 'small room'. Most cells are only visible under a microscope. Cells emerged on... | Cell (biology) | Wikipedia | 378 | 4230 | https://en.wikipedia.org/wiki/Cell%20%28biology%29 | Biology and health sciences | Science and medicine | null |
Prokaryotes include bacteria and archaea, two of the three domains of life. Prokaryotic cells were the first form of life on Earth, characterized by having vital biological processes including cell signaling. They are simpler and smaller than eukaryotic cells, and lack a nucleus, and other membrane-bound organelles. Th... | Cell (biology) | Wikipedia | 507 | 4230 | https://en.wikipedia.org/wiki/Cell%20%28biology%29 | Biology and health sciences | Science and medicine | null |
Plants, animals, fungi, slime moulds, protozoa, and algae are all eukaryotic. These cells are about fifteen times wider than a typical prokaryote and can be as much as a thousand times greater in volume. The main distinguishing feature of eukaryotes as compared to prokaryotes is compartmentalization: the presence of me... | Cell (biology) | Wikipedia | 453 | 4230 | https://en.wikipedia.org/wiki/Cell%20%28biology%29 | Biology and health sciences | Science and medicine | null |
All cells, whether prokaryotic or eukaryotic, have a membrane that envelops the cell, regulates what moves in and out (selectively permeable), and maintains the electric potential of the cell. Inside the membrane, the cytoplasm takes up most of the cell's volume. Except red blood cells, which lack a cell nucleus and mo... | Cell (biology) | Wikipedia | 392 | 4230 | https://en.wikipedia.org/wiki/Cell%20%28biology%29 | Biology and health sciences | Science and medicine | null |
The cytoskeleton acts to organize and maintain the cell's shape; anchors organelles in place; helps during endocytosis, the uptake of external materials by a cell, and cytokinesis, the separation of daughter cells after cell division; and moves parts of the cell in processes of growth and mobility. The eukaryotic cytos... | Cell (biology) | Wikipedia | 483 | 4230 | https://en.wikipedia.org/wiki/Cell%20%28biology%29 | Biology and health sciences | Science and medicine | null |
A human cell has genetic material contained in the cell nucleus (the nuclear genome) and in the mitochondria (the mitochondrial genome). In humans, the nuclear genome is divided into 46 linear DNA molecules called chromosomes, including 22 homologous chromosome pairs and a pair of sex chromosomes. The mitochondrial gen... | Cell (biology) | Wikipedia | 331 | 4230 | https://en.wikipedia.org/wiki/Cell%20%28biology%29 | Biology and health sciences | Science and medicine | null |
Cell nucleus: A cell's information center, the cell nucleus is the most conspicuous organelle found in a eukaryotic cell. It houses the cell's chromosomes, and is the place where almost all DNA replication and RNA synthesis (transcription) occur. The nucleus is spherical and separated from the cytoplasm by a double mem... | Cell (biology) | Wikipedia | 353 | 4230 | https://en.wikipedia.org/wiki/Cell%20%28biology%29 | Biology and health sciences | Science and medicine | null |
Endoplasmic reticulum: The endoplasmic reticulum (ER) is a transport network for molecules targeted for certain modifications and specific destinations, as compared to molecules that float freely in the cytoplasm. The ER has two forms: the rough ER, which has ribosomes on its surface that secrete proteins into the ER, ... | Cell (biology) | Wikipedia | 463 | 4230 | https://en.wikipedia.org/wiki/Cell%20%28biology%29 | Biology and health sciences | Science and medicine | null |
Ribosomes: The ribosome is a large complex of RNA and protein molecules. They each consist of two subunits, and act as an assembly line where RNA from the nucleus is used to synthesise proteins from amino acids. Ribosomes can be found either floating freely or bound to a membrane (the rough endoplasmatic reticulum in e... | Cell (biology) | Wikipedia | 501 | 4230 | https://en.wikipedia.org/wiki/Cell%20%28biology%29 | Biology and health sciences | Science and medicine | null |
Flagella are organelles for cellular mobility. The bacterial flagellum stretches from cytoplasm through the cell membrane(s) and extrudes through the cell wall. They are long and thick thread-like appendages, protein in nature. A different type of flagellum is found in archaea and a different type is found in eukaryote... | Cell (biology) | Wikipedia | 409 | 4230 | https://en.wikipedia.org/wiki/Cell%20%28biology%29 | Biology and health sciences | Science and medicine | null |
Cells of all organisms contain enzyme systems that scan their DNA for damage and carry out repair processes when it is detected. Diverse repair processes have evolved in organisms ranging from bacteria to humans. The widespread prevalence of these repair processes indicates the importance of maintaining cellular DNA in... | Cell (biology) | Wikipedia | 371 | 4230 | https://en.wikipedia.org/wiki/Cell%20%28biology%29 | Biology and health sciences | Science and medicine | null |
Transcription is the process where genetic information in DNA is used to produce a complementary RNA strand. This RNA strand is then processed to give messenger RNA (mRNA), which is free to migrate through the cell. mRNA molecules bind to protein-RNA complexes called ribosomes located in the cytosol, where they are tra... | Cell (biology) | Wikipedia | 426 | 4230 | https://en.wikipedia.org/wiki/Cell%20%28biology%29 | Biology and health sciences | Science and medicine | null |
In complex multicellular organisms, cells specialize into different cell types that are adapted to particular functions. In mammals, major cell types include skin cells, muscle cells, neurons, blood cells, fibroblasts, stem cells, and others. Cell types differ both in appearance and function, yet are genetically identi... | Cell (biology) | Wikipedia | 440 | 4230 | https://en.wikipedia.org/wiki/Cell%20%28biology%29 | Biology and health sciences | Science and medicine | null |
Small molecules needed for life may have been carried to Earth on meteorites, created at deep-sea vents, or synthesized by lightning in a reducing atmosphere. There is little experimental data defining what the first self-replicating forms were. RNA may have been the earliest self-replicating molecule, as it can both s... | Cell (biology) | Wikipedia | 408 | 4230 | https://en.wikipedia.org/wiki/Cell%20%28biology%29 | Biology and health sciences | Science and medicine | null |
In 1665, Robert Hooke examined a thin slice of cork under his microscope, and saw a structure of small enclosures. He wrote "I could exceeding plainly perceive it to be all perforated and porous, much like a Honey-comb, but that the pores of it were not regular". To further support his theory, Matthias Schleiden and Th... | Cell (biology) | Wikipedia | 367 | 4230 | https://en.wikipedia.org/wiki/Cell%20%28biology%29 | Biology and health sciences | Science and medicine | null |
In computer science, binary search, also known as half-interval search, logarithmic search, or binary chop, is a search algorithm that finds the position of a target value within a sorted array. Binary search compares the target value to the middle element of the array. If they are not equal, the half in which the targ... | Binary search | Wikipedia | 427 | 4266 | https://en.wikipedia.org/wiki/Binary%20search | Mathematics | Algorithms | null |
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