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  • Best, George (Irish-born football player)

    George Best, Irish-born football (soccer) player who was one of the premier forwards in the game’s history and a fashionable playboy off the field. The stylish Best became one of the iconic figures of “Swinging London” during the 1960s. While still a schoolboy, Best was recommended to Manchester

  • Best, Pete (British musician)

    the Beatles: …1962, Hamburg, West Germany) and Pete Best (b. November 24, 1941, Madras [now Chennai], India).

  • best-seller

    Best seller, book that, for a time, leads all others of its kind in sales, a designation that serves as an index of popular literary taste and judgment. Bookman, an American magazine of literature and criticism, began running best-seller lists in 1895, when it began publication. The list was

  • BEST1 (gene)

    macular degeneration: Other forms of macular degeneration: … in a gene known as BEST1 (bestrophin 1). Stargardt macular dystrophy, which is the most common genetic form of macular degeneration, is the only form inherited in an autosomal recessive manner (disease occurs only when mutations are inherited from both parents). It is caused by mutations in a gene called…

  • Bestām (Sasanian king)

    ancient Iran: Conflicts with the Turks and Byzantium: Simultaneously another pretender, Prince Bestām, decided to try his luck. Khosrow fled to Byzantium, and the emperor Maurice undertook to restore him by military force. Bahrām Chūbīn was routed (591) and fled to and was killed by the Turks, and Khosrow again ascended the throne in Ctesiphon. Bestām held…

  • Bestam (Iran)

    Bas?ām, small historic town, northern Iran. It lies just south of the Elburz Mountains in a well-watered plain. Clustered around the tomb of the poet and mystic Abū Yazīd al-Bis?āmī (d. 874) are a mausoleum, a 12th-century minaret and mosque wall, a superb portal (1313), and a 15th-century college.

  • Bes?āmī, Bāyazīd al- (?ūfī mystic)

    mushāhadah: …the famous mystic Bāyazīd al-Bes?āmī (d. 874) was asked how old he was, he replied “four years.” When asked for an explanation, he answered, “I have been veiled from God by this world for seventy years, but I have seen Him during the last four years; the period in…

  • Bester, Alfred (American author)

    Alfred Bester, innovative American writer of science fiction whose output, though small, was highly influential. Bester attended the University of Pennsylvania (B.A., 1935). From 1939 to 1942 he published 14 short stories in science-fiction magazines; among these early stories was “Hell Is Forever”

  • Bestiaires, Les (work by Montherlant)

    bullfighting: Bullfighting and the arts: …de Montherlant’s Les Bestiaires (1926; The Bullfighters) also deals with the matador’s ever-present threat of death in the ring.

  • bestiality (sexual behaviour)

    Zoophilia, sexual attraction of a human toward a nonhuman animal, which may involve the experience of sexual fantasies about the animal or the pursuit of real sexual contact with it (i.e., bestiality). Sex between humans and animals is illegal in many countries. (See also human sexual behaviour:

  • Bestiario (short stories by Cortázar)

    Julio Cortázar: Bestiario (1951; “Bestiary”), his first short-story collection, was published the year he moved to Paris, an act motivated by dissatisfaction with the government of Juan Perón and what he saw as the general stagnation of the Argentine middle class. He remained in Paris, where he…

  • Bestiary (Middle English work)

    English literature: Influence of French poetry: The early 13th-century Bestiary mixes alliterative lines, three- and four-stress couplets, and septenary (heptameter) lines, but the logic behind this mix is more obvious than in the Brut and the Proverbs, for the poet was imitating the varied metres of his Latin source. More regular in form than…

  • bestiary (medieval literary genre)

    Bestiary, literary genre in the European Middle Ages consisting of a collection of stories, each based on a description of certain qualities of an animal, plant, or even stone. The stories presented Christian allegories for moral and religious instruction and admonition. The numerous manuscripts

  • Bestie von Belsen (Nazi commander)

    Josef Kramer, German commander of the Bergen-Belsen concentration camp (1944–45), notorious for his cruelty. Joining the Nazi Party on Dec. 1, 1931, Kramer volunteered for the SS the following year. He served at various camps, including Auschwitz, Mauthausen, and Dachau, and commanded Birkenau

  • Bestimmung des Menschen, Die (work by Fichte)

    Johann Gottlieb Fichte: Years in Berlin: …Die Bestimmung des Menschen (1800; The Vocation of Man), in which he defines God as the infinite moral will of the universe who becomes conscious of himself in individuals; Der geschlossene Handelsstaat (also 1800), an intensely socialistic treatise in favour of tariff protection; two new versions of the Wissenschaftslehre (composed…

  • bestrophin 1 (gene)

    macular degeneration: Other forms of macular degeneration: … in a gene known as BEST1 (bestrophin 1). Stargardt macular dystrophy, which is the most common genetic form of macular degeneration, is the only form inherited in an autosomal recessive manner (disease occurs only when mutations are inherited from both parents). It is caused by mutations in a gene called…

  • Bestuzhev-Ryumin, Aleksey Petrovich, Count (Russian statesman)

    Aleksey Petrovich, Count Bestuzhev-Ryumin, diplomat and statesman who controlled Russia’s foreign affairs during the reign of the empress Elizabeth. Sent by Peter the Great to Copenhagen and Berlin for his education, Bestuzhev began his diplomatic career in the service of the Elector of Hanover at

  • Besuch der alten Dame, Der (play by Dürrenmatt)

    The Visit, drama in three acts by Swiss playwright Friedrich Dürrenmatt, performed and published in German in 1956 as Der Besuch der alten Dame. The play’s protagonist Claire, a multimillionaire, visits her hometown after an absence of many years and offers the residents great wealth if they will

  • Besy (novel by Dostoyevsky)

    The Possessed, novel by Fyodor Dostoyevsky, published in Russian in 1872 as Besy. The book, also known in English as The Devils and The Demons, is a reflection of Dostoyevsky’s belief that revolutionists possessed the soul of Russia and that, unless exorcised by a renewed faith in Orthodox

  • Beszterce ostroma (work by Mikszáth)

    Kálmán Mikszáth: …he published his first novel, Beszterce ostroma (“The Siege of Beszterce”), the story of an eccentric Hungarian aristocrat. Mikszáth’s early art is romantic. Toward the end of the century he became more realistic as the writer of everyday life, which he described with understanding and sympathy, though he did not…

  • Besztercebánya (Slovakia)

    Banská Bystrica, town, capital of Banskobystricky kraj (region), central Slovakia. It lies in the Hron River valley, surrounded by mountains. An ancient town, it was an important mining centre from the 13th century, when it was chartered. Gothic and Renaissance-style buildings, including burghers’

  • BET (former prefecture, Chad)

    Borkou-Ennedi-Tibesti (BET), former large prefecture (administrative division) of northern Chad. The region occupies much of the southeast-central portion of the Sahara, and the terrain is primarily low-lying arid desert that rises in the northwest to the lofty massif of the Tibesti. The sparse

  • bet (floodplain)

    Pakistan: The Indus River plain: …locally as a khaddar or bet), which lies adjacent to a river, is often called “the summer bed of rivers,” as it is inundated almost every rainy season. It is the scene of changing river channels, though protective bunds (levees) have been built at many places on the outer margin…

  • BET (American company)

    Black Entertainment Television (BET), American cable television network and multimedia group providing news, entertainment, and other programming developed primarily for African American viewers. BET also operates a channel geared toward African American women, BET Her; features contemporary and

  • Bet Alfa (archaeological site, Israel)

    Bet Alfa, ancient site in northeastern Israel, noted for the remains of a synagogue (founded 6th century ad) that was discovered in 1928 by kibbutz workers digging drainage ditches. The kibbutz was founded in 1922 by Polish Jewish immigrants, who revived the historical name of Bet Alfa for their

  • bet din (Judaism)

    Bet din, Jewish tribunal empowered to adjudicate cases involving criminal, civil, or religious law. The history of such institutions goes back to the time the 12 tribes of Israel appointed judges and set up courts of law (Deuteronomy 16:18). During the period of the Second Temple of Jerusalem (516

  • bet ha-she?uvah (Judaism)

    Judaism: Pilgrim Festivals: …libation ceremony, and the nightly bet ha-sho?eva or bet ha-she?uvah (“place of water drawing”) festivities starting on the evening preceding the second day. The last-mentioned observance features torch dancing, flute playing, and other forms of musical and choral entertainment.

  • bet ha-sho?eva (Judaism)

    Judaism: Pilgrim Festivals: …libation ceremony, and the nightly bet ha-sho?eva or bet ha-she?uvah (“place of water drawing”) festivities starting on the evening preceding the second day. The last-mentioned observance features torch dancing, flute playing, and other forms of musical and choral entertainment.

  • Bet Hillel (Judaism)

    Shammai ha-Zaken (“the Elder”): …with that of Hillel (Bet Hillel), which advocated more flexible interpretations. Shammai is cited in the Talmud and its commentaries in such a way as to emphasize his austere views. Bet Shammai opposed the Bet Hillel “principle of intention,” which holds that the legal consequences of a man’s act…

  • Bet Le?em (town, West Bank)

    Bethlehem, town in the West Bank, situated in the Judaean Hills 5 miles (8 km) south of Jerusalem. According to the Gospels (Matthew 2; Luke 2), Bethlehem was the site of the Nativity of Jesus Christ. Christian theology has linked this with the belief that his birth there fulfills the Old Testament

  • Bet Shammai (Judaism)

    Shammai ha-Zaken (“the Elder”): …best remembered for the school, Bet Shammai (“House of Shammai”), that he founded. His school, which advocated a strict, literal interpretation of Jewish law, competed with that of Hillel (Bet Hillel), which advocated more flexible interpretations. Shammai is cited in the Talmud and its commentaries in such a way as…

  • Bet She?an (Israel)

    Bet She?an, town, northeastern Israel, principal settlement in the low ?Emeq Bet She?an (?emeq, “valley”), site of one of the oldest inhabited cities of ancient Palestine. It is about 394 ft (120 m) below sea level. Overlooking the town to the north is Tel Bet She?an (Arabic Tall al-?u?n), one of

  • Bet She?an, Tel (archaeological site, Israel)

    Palestine: Early Bronze Age: Jericho, Tall al-Far?ah, Tel Bet She?an, Khirbat al-Karak, and Ai (Khirbat ?Ayy). All these sites are in northern or central Palestine, and it was there that the Early Bronze Age towns seem to have developed. The towns of southern Palestine—for instance, Tel Lakhish, Kiriath-sepher, and Tel ?asi—seem only…

  • Bet She?arim (Israel)

    Bet She?arim, agricultural cooperative settlement (moshav) and archaeological site in northern Israel, near the western end of the Plain of Esdraelon. Ancient Bet She?arim (Hebrew: House [of the] Gates), about 3 mi (5 km) east-northeast of the modern settlement (founded in 1936), is frequently

  • Bet Twice (racehorse)

    Alysheba: …by jockey Chris McCarron, challenged Bet Twice at the top of the stretch, inched ahead, and won by half a length. Once again, the time was slow, the slowest since 1975, but the horses achieved the first one-two finish in the Derby and the Preakness since Affirmed and Alydar did…

  • Bet Yerah (ancient site, Palestine)

    Beth Yerah, ancient fortified settlement located at the southern tip of the Sea of Galilee. Beth Yerah was settled in the Early Bronze Age (c. 3100–2300 bc) and was also populated from the Hellenistic to the Arab periods (c. 2nd century bc to 12th century ad). Archaeological findings suggest that

  • Bet Yosef (work by Karo)

    Joseph ben Ephraim Karo: …codification of Jewish law, the Bet Yosef (“House of Joseph”). Its condensation, the Shul?an ?arukh (“The Prepared Table,” or “The Well-Laid Table”), is still authoritative for Orthodox Jewry.

  • Beta (plant genus)

    Caryophyllales: Amaranthaceae: Cultivars of Beta vulgaris are vegetable crops, including the sugar beet and the garden beet, or beetroot. The beet’s leaves are similar in taste to spinach (Spinacia oleracea, of the same family). The root may be dark purplish red, yellow, white, or striped. It can be boiled…

  • beta (investment risk)

    William F. Sharpe: …to the concept of “beta,” a measurement of portfolio risk. Investment analysts frequently use a beta coefficient to compare the risk of one stock against the risk of the broader stock market.

  • beta alloy (metallurgy)

    titanium processing: Alpha and beta phases: pure, alpha, alpha-beta, and beta. Each class has distinctive characteristics. Pure titanium, although very ductile, has low strength and is therefore used when strength is not critical and corrosion resistance is desired. The alpha alloys are weldable and have good elevated-temperature strengths. The alpha-beta alloys are widely used because…

  • beta brass (alloy)

    brass: Characteristics of the alloy: The beta brasses are less ductile but stronger and thus are suitable for the manufacture of faucet handles, sprinkler heads, window and door fittings, and other fixtures. A third group of brasses includes those with other elements besides copper and zinc, added to improve physical and…

  • Beta Cancri (star)

    Cancer: Its brighest star, Al Tarf (Arabic for “the end” [of one of the crab’s legs]), also called Beta Cancri, is quite dim, with a magnitude of 3.6.

  • Beta Canis Majoris variable star (astronomy)

    star: Pulsating stars: …of pulsating variable stars, the Beta Canis Majoris variables are high-temperature stars (spectral type B) that often show complicated variations in spectral-line shapes and intensities, velocity curves, and light. In many cases, they have two periods of variation so similar in duration that complex interference or beat phenomena are observed,…

  • beta cell (biology)

    islets of Langerhans: …types, of which three (alpha, beta, and delta cells) produce important hormones; the fourth component (C cells) has no known function.

  • Beta Centauri (star)

    Beta Centauri, second brightest star (after Alpha Centauri) in the southern constellation Centaurus and the 10th brightest star in the sky. Beta Centauri is about 390 light-years from Earth. It is a system of three B-type stars. The two brightest stars orbit each other every 357 days and form a

  • Beta Crucis (star)

    Beta Crucis, second brightest star (after Alpha Crucis) in the southern constellation Crux (the Southern Cross) and the 20th brightest star in the sky. Beta Crucis is a binary of two B-type stars about 280 light-years from Earth. The primary is a pulsating variable star of the Beta Cephei type; its

  • Beta Cygni (star)

    astronomical map: Star names and designations: A conspicuous exception is Albireo in Cygnus, possibly a corruption of the words ab ireo in the first Latin edition of the Almagest in 1515. Most star names are in fact Arabic and are frequently derived from translations of the Greek descriptions. The stars of Orion illustrate the various…

  • beta decay (physics)

    Beta decay, any of three processes of radioactive disintegration by which some unstable atomic nuclei spontaneously dissipate excess energy and undergo a change of one unit of positive charge without any change in mass number. The three processes are electron emission, positron (positive electron)

  • beta effect (science)

    climate: The Gulf Stream: …with latitude known as the beta effect. This effect involves the displacement of the warm water lens toward the west, so that the deepest part of the lens is situated to the north of the island of Bermuda rather than in the central Atlantic Ocean. This warm lens of water…

  • beta emission (physics)

    Beta decay, any of three processes of radioactive disintegration by which some unstable atomic nuclei spontaneously dissipate excess energy and undergo a change of one unit of positive charge without any change in mass number. The three processes are electron emission, positron (positive electron)

  • Beta Geminorum (star)

    Pollux, brightest star in the zodiacal constellation Gemini. A reddish giant star, it has an apparent visual magnitude of 1.15. The stars Castor and Pollux are named for the mythological twins. Pollux is 33.7 light-years from Earth. In 2006 a planet, Pollux b, was discovered. Pollux b has nearly

  • beta globulin (protein)

    globulin: …of globulin have been identified—alpha, beta, and gamma. Alpha and beta globulins are transport proteins, serve as substrates upon which other substances are formed, and perform other diverse functions. Gamma globulins have a vital role in natural and acquired immunity to infection. See also gamma globulin.

  • beta interferon (biochemistry)

    interferon: Three forms of interferon—alpha (α), beta (β), and gamma (γ)—have been recognized. These interferons have been classified into two types: type I includes the alpha and beta forms, and type II consists of the gamma form. This division is based on the type of cell that produces the interferon and…

  • beta iron (mining)

    steel: The base metal: iron: There is also the term beta iron, which refers not to mechanical properties but rather to the strong magnetic characteristics of iron. Below 770° C (1,420° F), iron is ferromagnetic; the temperature above which it loses this property is often called the Curie point.

  • Beta Israel (people)

    Beta Israel, Jews of Ethiopian origin. Their beginnings are obscure and possibly polygenetic. The Beta Israel (meaning House of Israel) themselves claim descent from Menilek I, traditionally the son of the Queen of Sheba (Makeda) and King Solomon. At least some of their ancestors, however, were

  • Beta Lyrae (star)

    Beta Lyrae, eclipsing binary star, the two component stars of which are so close together that they are greatly distorted by their mutual attraction; they exchange material and share a common atmosphere. Beta Lyrae is a member of a class of binary systems known as W Serpentis stars. It is of about

  • Beta Orionis (star)

    Rigel, one of the brightest stars in the sky, intrinsically as well as in appearance. A blue-white supergiant in the constellation Orion, Rigel is about 870 light-years from the Sun and is about 47,000 times as luminous. A companion double star, also bluish white, is of the sixth magnitude. The

  • beta particle (physics)

    Beta particle, electron (unit negative charge) or positron (unit positive charge) spontaneously emitted by certain unstable atomic nuclei in the radioactive disintegration process of beta decay

  • Beta Persei (star)

    Algol, prototype of a class of variable stars called eclipsing binaries, the second brightest star in the northern constellation Perseus. Its apparent visual magnitude changes over the range of 2.1 to 3.4 with a period of 2.87 days. Even at its dimmest it remains readily visible to the unaided eye.

  • beta phase (chemistry)

    titanium processing: Alpha and beta phases: The atoms of pure titanium align in the solid state in either a hexagonal close-packed crystalline structure, called the alpha (α) phase, or a body-centred cubic structure, called the beta (β) phase. In the pure metal, transformation from the alpha to the beta…

  • Beta Pictoris (star)

    Beta Pictoris, fourth-magnitude star located 63 light-years from Earth in the southern constellation Pictor and notable for an encircling disk of debris that might contain planets. The star is of a common type somewhat hotter and more luminous than the Sun. In 1983 it was discovered to be an

  • beta radiation (physics)

    atom: Radioactive decay: …of fast electrons is called beta radiation. The daughter nucleus has one fewer neutron and one more proton than the original and hence, again, is a different chemical element.

  • beta ray (physics)

    atom: Radioactive decay: …of fast electrons is called beta radiation. The daughter nucleus has one fewer neutron and one more proton than the original and hence, again, is a different chemical element.

  • beta receptor (microbiology)

    catecholamine: …receptors, or alpha receptors and beta receptors, respectively. In general, activation of alpha-adrenergic receptors results in the constriction of blood vessels, contraction of uterine muscles, relaxation of intestinal muscles, and dilation of the pupils. Activation of beta-adrenergic receptors increases heart rate and stimulates cardiac contraction (thereby increasing cardiac output), dilates…

  • Beta Regio (Venus)

    Venus: Rifts: …broad, raised areas such as Beta Regio, sometimes radiating outward from their centres like the spokes of a giant wheel. Beta and several other similar regions on Venus appear to be places where large areas of the lithosphere have been forced upward from below, splitting the surface to form great…

  • beta rhythm (physiology)

    neural oscillation: Types of brain rhythms: Beta rhythms (13–30 Hz) are present throughout the motor system in the absence of movement, while transient beta oscillations (or sleep spindles) are present in the thalamocortical system during the early stages of sleep. Gamma oscillations (30–120 Hz) are present in nearly all structures and…

  • beta transus (chemistry)

    titanium processing: Alpha and beta phases: …can exist is called the beta transus; this can range from 700 °C (1,300 °F) to as high as 1,050 °C (1,900 °F), depending on alloy composition. Final mechanical working and heat treatments of titanium alloys are generally conducted below the beta transus temperature in order to achieve the proper…

  • Beta Ursae Minoris (star)

    navigation: Latitude measurements: …position of the nearby star Kochab. When the navigators got close to the Equator, these stars fell below the horizon; there it became necessary to rely on observing the altitude of the noonday Sun and calculating latitude with the aid of an almanac.

  • Beta vulgaris (plant)

    Beet, (Beta vulgaris), any of the four cultivated forms of the plant Beta vulgaris (family Amaranthaceae), grown for their edible leaves and roots. Each of the four distinct types of B. vulgaris is used differently: (1) the common garden beet (also called beetroot or table beet) is cultivated as a

  • Beta vulgaris cicla (plant)

    Chard, (Beta vulgaris, variety cicla), variety of the beet of the amaranth family (Amaranthaceae), grown for its edible leaves and leafstalks. Fresh chard is highly perishable and difficult to ship to distant markets. The young leaves can be eaten raw in salads, while larger leaves and stalks are

  • beta wave (physiology)

    neural oscillation: Types of brain rhythms: Beta rhythms (13–30 Hz) are present throughout the motor system in the absence of movement, while transient beta oscillations (or sleep spindles) are present in the thalamocortical system during the early stages of sleep. Gamma oscillations (30–120 Hz) are present in nearly all structures and…

  • beta-adrenergic blocking agent (drug)

    Beta-blocker, any of a group of synthetic drugs used in the treatment of a wide range of diseases and conditions of the sympathetic nervous system. Stimulation by epinephrine of beta-adrenoreceptors, which are predominately found in cells of the heart and also are present in vascular and other

  • beta-adrenergic receptor (microbiology)

    catecholamine: …receptors, or alpha receptors and beta receptors, respectively. In general, activation of alpha-adrenergic receptors results in the constriction of blood vessels, contraction of uterine muscles, relaxation of intestinal muscles, and dilation of the pupils. Activation of beta-adrenergic receptors increases heart rate and stimulates cardiac contraction (thereby increasing cardiac output), dilates…

  • beta-adrenergic receptor kinase (microbiology)

    Robert J. Lefkowitz: …discovered a molecule known as beta-adrenergic receptor kinase (beta-ARK), which regulates GPCR activity.

  • beta-adrenoreceptor (microbiology)

    catecholamine: …receptors, or alpha receptors and beta receptors, respectively. In general, activation of alpha-adrenergic receptors results in the constriction of blood vessels, contraction of uterine muscles, relaxation of intestinal muscles, and dilation of the pupils. Activation of beta-adrenergic receptors increases heart rate and stimulates cardiac contraction (thereby increasing cardiac output), dilates…

  • beta-alanine (chemical compound)

    alanine: D-alanine, or beta-alanine (β-alanine), is not found in proteins but occurs naturally in two peptides, carnosine and anserine, found in mammalian muscle. It is an important constituent of the vitamin pantothenic acid. The chemical structure of D-alanine is

  • beta-alumina (mining)

    corundum: Artificial corundum may be produced as a specialty product, as for gem use, by slow accretion and controlled growth on a boule in an oxyhydrogen flame. This procedure is known as the Verneuil process (q.v.).

  • beta-aminoisobutyric acid excretion

    Beta-aminoisobutyric acid excretion, a metabolic process under simple genetic control in human beings and the higher primates, the significance of which is not fully understood. Beta-aminoisobutyric acid (BAIB), an amino acid end product of pyrimidine metabolism, is excreted in trace quantities

  • beta-amylase (enzyme)

    amylase: Beta-amylases are present in yeasts, molds, bacteria, and plants, particularly in the seeds. They are the principal components of a mixture called diastase that is used in the removal of starchy sizing agents from textiles and in the conversion of cereal grains to fermentable sugars.…

  • beta-ARK (microbiology)

    Robert J. Lefkowitz: …discovered a molecule known as beta-adrenergic receptor kinase (beta-ARK), which regulates GPCR activity.

  • beta-arrestin (protein)

    Robert J. Lefkowitz: …later identified a protein called beta-arrestin, which acts on beta-ARK-phosphorylated GPCRs and which explained the phenomenon of GPCR desensitization in response to repeated agonist binding.

  • beta-blocker (drug)

    Beta-blocker, any of a group of synthetic drugs used in the treatment of a wide range of diseases and conditions of the sympathetic nervous system. Stimulation by epinephrine of beta-adrenoreceptors, which are predominately found in cells of the heart and also are present in vascular and other

  • beta-carotene (vitamin)

    chemical compound: Ultraviolet and visible (UV-visible) spectroscopy: …bright orange colour of carrots, β-carotene, contains 11 conjugated π bonds. UV-visible spectroscopy is especially informative for molecules that contain conjugated π bonds.

  • beta-cristobalite (mineral)

    cristobalite: …but is not stable; and high-cristobalite, which occurs above 268° C but is only stable above 1,470° C. Natural low-cristobalite usually occurs in sub-microcrystalline masses (see opal) or fibrous to columnar spherulites (see lussatite) in igneous rocks. Cristobalite has the same chemical composition as coesite, stishovite, quartz, and tridymite but…

  • beta-delayed alpha emission (physics)

    radioactivity: Special beta-decay processes: …electron decay from lithium-8 are beta-delayed alpha emission, because ground as well as excited states of beryllium-8 are unstable with respect to breakup into two alpha particles. Another example, sodium-20 (20Na) to give successively neon-20 (20Ne; the asterisk again indicating the short-lived intermediate state) and finally oxygen-16 is listed below:

  • beta-delayed neutron emission (physics)

    radioactivity: Special beta-decay processes: One such process is beta-delayed neutron emission, which is exemplified by the following reaction:

  • beta-delayed proton emission (physics)

    radioactivity: Special beta-decay processes: …not able to bind a proton. In these cases, proton radiation appears with the half-life of the beta transition. The combination of high positron-decay energy and low proton-binding energy in the daughter ground state is required. In the example given below, tellurium-111 (111Te) yields antimony-111 (111Sb) and then tin-110 (110Sn)…

  • beta-endorphin (chemical compound)

    enkephalin: …related substances known as beta-endorphins were discovered when investigators postulated that since exogenous (produced outside of the human body) opiate substances such as morphine bind to cell surface receptors, there must exist endogenous (produced inside the human body) opiate-like substances that do likewise and therefore have a narcotic action.…

  • beta-galactosidase (enzyme)

    metabolism: Coarse control: …enzyme of this type is β-galactosidase. Escherichia coli growing in nutrient medium containing glucose do not utilize the milk sugar, lactose (glucose-4-β-d-galactoside); however, if the bacteria are placed in a growth medium containing lactose as the sole source of carbon, they synthesize β-galactosidase and can therefore utilize lactose. The reaction…

  • beta-hydrogen elimination (chemistry)

    organometallic compound: β-hydrogen elimination: This is a common organometallic reaction in which a hydrogen atom on a carbon atom that is one position removed from the metal (the β position) transfers to the metal with the liberation of an alkene. The following example shows the formation of…

  • beta-hydroxyacyl coenzyme A (enzyme)

    metabolism: Fragmentation of fatty acyl coenzyme A molecules: The product, called a β-hydroxyacyl coenzyme A, can again be oxidized in an enzyme-catalyzed reaction [24]; the electrons removed are accepted by NAD+. The product is called a β-ketoacyl coenzyme A.

  • beta-hydroxybutyraldehyde (chemical compound)

    aldehyde: Aldol reaction: Another important reaction of a carbon nucleophile with an aldehyde is the aldol reaction (also called aldol condensation), which takes place when any aldehyde possessing at least one α-hydrogen is treated with sodium hydroxide or sometimes with another base. The product of an…

  • beta-hydroxybutyryl-S-ACP (chemical compound)

    metabolism: Fatty acids: …for example, undergoes reduction to β-hydroxybutyryl-S-ACP (reaction [65]); the reaction is catalyzed by β-ketoacyl-ACP reductase. Reduced NADP+ is the electron donor, however, and not reduced NAD+ (which would participate in the reversal of reaction [24]). NADP? is thus a product in [65].

  • beta-ketoacyl coenzyme A (enzyme)

    metabolism: Fragmentation of fatty acyl coenzyme A molecules: The product is called a β-ketoacyl coenzyme A.

  • beta-ketoacyl-ACP reductase (enzyme)

    metabolism: Fatty acids: …the reaction is catalyzed by β-ketoacyl-ACP reductase. Reduced NADP+ is the electron donor, however, and not reduced NAD+ (which would participate in the reversal of reaction [24]). NADP? is thus a product in [65].

  • beta-ketoacyl-ACP synthetase (enzyme)

    metabolism: Fatty acids: …in a reaction catalyzed by β-ketoacyl-ACP synthetase so that the acetyl moiety (CH3CO―) is transferred to the malonyl moiety (?OOCH2CO―). Simultaneously, the carbon dioxide fixed in step [62] is lost, leaving as a product a four-carbon moiety attached to ACP and called acetoacetyl-S-ACP (reaction [64]).

  • beta-lactamase (enzyme)

    Enterobacter: …of producing enzymes known as beta-lactamases, which cleave the central ring structure responsible for the activity of beta-lactam antibiotics, a group that includes imipenem (a type of carbapenem) and cephalosporins. Repeated exposure to these drugs selects for beta-lactamase-synthesizing Enterobacter, thereby giving rise to drug resistance, including against carbapenems, which were…

  • beta-minus decay (physics)

    radioactivity: Beta-minus decay: In beta-minus decay, an energetic negative electron is emitted, producing a daughter nucleus of one higher atomic number and the same mass number. An example is the decay of the uranium daughter product thorium-234 into protactinium-234:

  • beta-oxoacyl-S-ACP (chemical compound)

    metabolism: Fatty acids: …via reaction [64], successively longer β-oxoacyl-S-ACP derivatives are produced.

  • beta-plus decay

    beta decay: In positron emission, also called positive beta decay (β+-decay), a proton in the parent nucleus decays into a neutron that remains in the daughter nucleus, and the nucleus emits a neutrino and a positron, which is a positive particle like an ordinary electron in mass but…

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