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alpha interferon ... alpine permafrost

alpha interferon: (from the article "therapeutics") Interferon-alpha is produced by a recombinant DNA process using genetically engineered Escherichia coli. Recombinant interferon-alpha appears to be most effective against hairy-cell leukemia and chronic myelogenous leukemia, lymphoma, multiple myeloma, AIDS-associated Kaposi's sarcoma, and chronic type C hepatitis. It is moderately...production and uses
alpha iron: (from the article "iron") ...and is paramagnetic (weakly affected by a magnet); its ability to form solid solutions with carbon is important in steelmaking. At 912° C (1,674° F) there is a transition to paramagnetic alpha iron, which is also body-centred cubic in structure. Below 770° C (1,420° F), alpha iron becomes ferromagnetic, indicating ...
alpha motor fibre: (from the article "nervous system, human") In addition to receiving specialized fusimotor fibres, the muscle spindle may also receive, though on a less-regular basis, branches of ordinary extrafusal motor axons. Called alpha (alpha) efferents, these fibres have either a static or a dynamic effect. The physiologically important point is that most of the motor supply to ...
alpha particle: positively charged particle, identical to the nucleus of the helium-4 atom, spontaneously emitted by some radioactive substances, consisting of two protons and two neutrons bound together, thus having a mass of four units and a positive charge of two. Discovered and named (1899) by Ernest Rutherford, alpha particles were used ... [22 Related Articles]
alpha phase: (from the article "titanium processing") The atoms of pure titanium align in the solid state in either a hexagonal close-packed crystalline structure, called the alpha (alpha) phase, or a body-centred cubic structure, called the beta (beta) phase. In the pure metal, transformation from the alpha to the beta phase occurs upon heating above 883° C, ...
alpha receptor: (from the article "nervous system") Receptors sensitive to norepinephrine and epinephrine are called adrenergic receptors. They are divided into two types, alpha and beta. These are further classified into subtypes alpha₁, alpha₂, beta₁, and beta₂.catecholaminesendocrine system, humanCatecholamines...fact that there are two major types of adrenergic ...
Alpha Regio: (from the article "Venus") Tesserae (Latin: "mosaic tiles") are the most geologically complex regions seen on Venus. Several large elevated regions, such as Alpha Regio, are composed largely of tessera terrain. Such terrain appears extraordinarily rugged and highly deformed in radar images, and in some instances it displays several different trends of parallel ridges ...
Alpha Suffrage Club: (from the article "Wells-Barnett, Ida Bell") ...in organizing local African American women in various causes, from the antilynching campaign to the suffrage movement. She founded what may have been the first black woman suffrage group, Chicago's Alpha Suffrage Club.
alpha wave: (from the article "human behaviour") ...record of the brain's electrical activity. The normal human EEG displays continuous rhythmic activity in the form of wavelike patterns varying in frequency and amplitude. The dominant rhythm is the alpha wave, which reaches its maximum frequency in adolescence and begins to slow gradually after young adulthood. This slowing may ...
alpha-1 antitrypsin: (from the article "emphysema") ...decade of smoking. The reason that emphysema develops in some smokers but not in others is generally unknown. One factor that predisposes some individuals to emphysema is an inherited deficiency of alpha-1 antitrypsin, an enzyme that normally protects the lungs from injury caused by cigarette smoke. Smokers who inherit an ...
alpha-amylase: (from the article "amylase") Alpha-amylase is widespread among living organisms. In the digestive systems of humans and many other mammals, an alpha-amylase called ptyalin is produced by the salivary glands, whereas pancreatic amylase is secreted by the pancreas into the small intestine.composition of starchcereal ...
alpha-beta alloy: (from the article "titanium processing") Using the common phases present at room temperature, titanium alloys are divided into four classes: commercially 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 ...
alpha-beta receptor: (from the article "immune system") ...T-cell receptors were difficult to isolate in the laboratory and were not identified until 1983. T-cell receptors consist of two polypeptide chains. The most common type of receptor is called alpha-beta because it is composed of two different chains, one called alpha and the other beta (see illustration). A less ...
alpha-fetoprotein: (from the article "diagnosis") The most common screening test is an assay of alpha-fetoprotein (AFP) in the maternal serum. Elevated levels are associated with neural tube defects in the fetus such as spina bifida (defective closure of the spine) and anencephaly (absence of brain tissue). When alpha-fetoprotein levels are elevated, a more specific diagnosis ...
alpha-helium radioactive clock: (from the article "helium dating") ...are measured, the helium dating method is referred to as uranium-thorium-helium dating; if only the alpha-particle emission and helium content are measured, the method is called the alpha-helium radioactive clock. Alpha particles are the nuclei of helium atoms emitted from the nucleus of the radioactive progenitor.
alpha-linolenic acid: (from the article "Common fatty acids in foods") ...clotting, preventing irregular heart rhythms, and acting as anti-inflammatory agents. The long-chain omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are derived from alpha-linolenic acid, a shorter-chain member of the same family. Fatty fish such as salmon, herring, sardines, mackerel, and tuna are high in both EPA and ...
alpha-oxoglutarate: (from the article "metabolism") ...of only three possible substances: the two-carbon compound acetate, in the form of a compound called acetyl coenzyme A (Figure 1); the four-carbon compound oxaloacetate; and the five-carbon compound alpha-oxoglutarate. The first, acetate in the form of acetyl coenzyme A, constitutes by far the most common product-it is the product ...
alpha-particle welding: (from the article "radiation") ...(such as an alpha-particle or proton); the resultant nucleus is often but not always radioactive. As an example, the reaction of neutrons on boron to produce alpha particles provides the basis for alpha-particle welding. The principle of such welding, invented by the Soviet chemist V.I. Goldansky, is to deposit a ...
alpha-thalassemia: (from the article "blood disease") The defect in thalassemia may involve the beta-chains of globin (beta-thalassemia), the alpha-chains (alpha-thalassemia), the delta-chains (delta-thalassemia), or both delta- and beta-chain synthesis. In the last (delta-beta-thalassemia), Hb F concentrations usually are considerably elevated since the number of beta-chains available to combine with alpha-chains is...types of thalassemia
alphabet: (from the article "information processing") At some point in the evolution of written languages, the method of representation shifted from the pictographic to the phonetic: speech sounds began to be represented by an alphabet of graphic symbols. Combinations of a relatively small set of such symbols could stand for more complex concepts as words, phrases, ...
alphabet: set of graphs, or characters, used to represent the phonemic structure of a language. In most alphabets the characters are arranged in a definite order, or sequence (e.g., A, B, C, etc.). [9 Related Articles]
alphabet rhyme: mnemonic verse or song used to help children learn an alphabet; such devices appear in almost every alphabetic language. Some of the early English favourites are about 300 years old and have served as models for countless variations. One is a cumulative rhyme to which there is a printed reference ...
alphabetic writing: (from the article "language") ...consonant sounds. By a stroke of genius, a Greek community decided to employ certain consonantal signs to which no consonant sound corresponded in Greek as independent vowel signs, thus producing an alphabet, a set of letters standing for consonants and vowels. The Greek alphabet spread over the ancient Greek world, ...
Alphaherpesvirinae: (from the article "virus") ...with capsid about 105 nm in diameter and 162 capsomeres surrounded by a floppy envelope containing glycoprotein spikes. Genome composed of linear double-stranded DNA. There are 3 known subfamilies: Alphaherpesvirinae, consisting of human herpes simplex viruses types 1 and 2, bovine mamillitis virus, SA8 virus and monkey B virus, pseudorabies ...
alphametic: (from the article "number game") Such puzzles had apparently appeared, on occasion, even earlier. Alphametics refers specifically to cryptarithms in which the combinations of letters make sense, as in one of the oldest and probably best known of all alphametics:
alphanumeric photocomposition system: (from the article "printing") ...binary analysis of its design available in its magnetic memory; this is, in fact, all that is needed to modulate the pencil of electrons on the final screen. Phototypesetters of this kind (called alphanumerical) have theoretical performance rates exceeding 3,000 characters per second, or more than 10,000,000 per hour, and ...
alphaprodine: (from the article "drug use") ...a constant search for synthetic substitutes: meperidine (Demerol), first synthesized in Germany in 1939, is a significant addition to the group of analgesics, being one-tenth as potent as morphine; alphaprodine (Nisentil) is one-fifth as potent as morphine but is rapid-acting; methadone, synthesized in Germany during World War II, is comparable ...
Alphavirus: (from the article "virus") ...nucleocapsid of 32 capsomeres about 30 nm in diameter. The genome is single positive-strand RNA. There are 2 recognized genera: 1 transmitted by arthropods (exclusively mosquitoes) and designated alphaviruses (prototypes Sindbis virus, eastern and western equine encephalitis viruses), the other non-arthropod-borne and designated rubivirus (the causative agent of German...type of ...
Alpher, Ralph Asher: American physicist laid the foundations for the big-bang model, a widely held theory of the evolution of the universe, while a graduate student at the George Washington University, Washington, D.C. Though Alpher had set forth calculations and theoretical predictions about the origins of the universe in his doctoral dissertation, his ... [1 Related Articles]
Alpheus: (from the article "Arethusa") The river god Alpheus fell in love with Arethusa, who was in the retinue of Artemis. Arethusa fled to Ortygia, where she was changed into a spring. Alpheus, however, made his way beneath the sea and united his waters with those of the spring. According to Ovid's Metamorphoses, Book V, ...
Alpheus River: river, the longest of the Peloponnese (Peloponnisos), Greece, rising near Dhavia in central Arcadia, with a course of about 70 mi (110 km). Leaving the plain of Megalopolis in a rugged gorge, above which it is known as the Elisson, the Alpheus turns abruptly northwest and eventually empties into the ...
Alphonse of Poitiers: (from the article "Crusades") ...smaller vessels got under way. Fortune favoured them at first, and Damietta was again in Christian hands by June. Shortly afterward the army was strengthened by the arrival of Louis's third brother, Alphonse of Poitiers. Sultan al-Salih Ayyub's death was followed by confusion in Cairo, which, after some argument, had ...
Alphonsus: (from the article "Moon") ...to sinuous rilles, there are straight and branching rilles that appear to be tension cracks, and some of these-such as Rima Hyginus and the rilles around the floor of the large old crater Alphonsus-are peppered with rimless eruption craters. Though the Moon shows both tension and compression features (low wrinkle ...
alphorn: long horn played by Alpine herdsmen and villagers, sounded for intercommunication and at daily ceremonies and seasonal festivals. It is carved or bored in wood and overwound with birch bark. Some instruments are straight, reaching 12 feet (4 metres) in length; since the mid-19th century, especially in Switzerland, the bell ... [1 Related Articles]
Alpide Belt: (from the article "earthquake") A second belt, known as the Alpide Belt, passes through the Mediterranean region eastward through Asia and joins the Circum-Pacific Belt in the East Indies. The energy released in earthquakes from this belt is about 15 percent of the world total. There also are striking connected belts of seismic activity, ...
Alpine: city, seat (1887) of Brewster county, extreme western Texas, U.S., in a high valley with an altitude of 4,481 feet (1,366 metres), flanked by the Davis Mountains (north) and the Glass Mountains (east), 190 miles (306 km) southeast of El Paso.
alpine accentor: (from the article "accentor") The alpine accentor (Prunella collaris), which ranges from Spain and northwestern Africa to Japan, is at 18 cm (7 inches) long the largest and stoutest of the accentors. Both sexes are mostly brown with reddish-spotted flanks and a heavily stippled throat. In courtship the male warbles a rippling larklike call ...
Alpine Asia: (from the article "Asia") Alpine Asia-sometimes known as High Asia-includes the Pamirs and the eastern Hindu Kush, the Kunlun Mountains, the Tien Shan, the Gissar and Alay ranges, the Plateau of Tibet, the Karakoram Range, and the Himalayas. The Pamirs and the eastern Hindu Kush are sharply uplifted mountains dissected into ridges and gorges ...
alpine chough: (from the article "chough") ...bills. In the family Corvidae (q.v.; order Passeriformes) are the common chough (Pyrrhocorax pyrrhocorax), of sea cliffs and rocky uplands from the British Isles to China, and the alpine chough (P. graculus), of high mountains from Morocco and Spain to the Himalayas. Both are about 38 cm (15 inches) long ...
Alpine climbing: (from the article "Everest, Mount") ...to focus instead on only achieving the summit. Top mountaineers, disenchanted with the ponderous and predictable nature of these siege climbs, began in the 1970s to bring a more traditional "Alpine" style of climbing to the world's highest peaks; by the 1980s this included even Everest. In this approach, a ...
Alpine Club: (from the article "Everest, Mount") ...India, met and began discussing the possibility of an expedition to Everest. The officers became involved with two British exploring organizations-the Royal Geographical Society (RGS) and the Alpine Club-and these groups became instrumental in fostering interest in exploring the mountain. Bruce and Younghusband sought permission to mount an Everest expedition ...
Alpine club moss: (from the article "club moss") ...obscurum), a 25-cm-tall plant, has underground-running stems. It is native to moist woods and bog margins in northern North America, to mountain areas farther south, and to eastern Asia. Alpine club moss (Lycopodium alpinum), with yellowish or grayish leaves, is native to cold woods and Alpine mountains in northern North ...
alpine currant: (from the article "Ribes") ...(R. hirtellum), black currant (R. nigrum), buffalo currant (R. odoratum), and common, or garden or red, currant (R. rubrum). Species of ornamental value include the alpine currant (R. alpinum); buffalo currant; fuchsia-flowered gooseberry (R. speciosum); golden, or clove, currant (R. aureum), bearing spicy-fragrant yellow flowers; and R....
alpine desert: (from the article "mountain ecosystem") ...remains until late spring or summer, snowbed communities occur that are dominated by the heather Phyllodoce or by sedges (species of Carex), with many other small plants also present. Alpine deserts are also widespread in the high mountains of Japan, in places with marked soil instability associated with the effects ...
Alpine folk cultures: (from the article "interior design") In many areas of Europe, Renaissance, Baroque, and Rococo had little effect on interior decoration. In the Alpine lands, where wood was cheap and plentiful, traditional medieval methods continued for a long time. Wooden floors and ceilings and panelled walls, or partly panelled with plain plaster above, were the general ...
Alpine Foreland: (from the article "Baden-Wurttemberg") The Alpine Foreland is a deep trough at the edge of the Alps stretching from the formerly volcanic area of the Hegau Mountains in the west to the meadows of the Allgau in the east. Within its area lies the famous Lake Constance and numerous rolling hills with many lakes ...
Alpine Geosyncline: (from the article "Caucasus") The greater part of Caucasia originated in the vast structural downwarp in the Earth's crust known as the Alpine geosyncline, dating from the Late Oligocene Epoch (about 28.5 to 23.8 million years ago), and the region thus reflects some of the same structural characteristics as the younger mountains of Europe. ...
Alpine lakes: the 11 significant European lakes fringing the great mountainous mass of the Alps. Set in magnificent scenery, they are the focus of considerable settlement and a thriving tourist traffic, as well as of great scientific interest.
Alpine meadow: (from the article "Alps") ...cutting the trees is strictly controlled. Above the tree line and below the permanent snow line, a distance of about 3,000 feet, are areas eroded by glaciation that in places are covered with lush Alpine meadows. There sheep and cows are grazed during the short summer, a factor that has ...
Alpine orogeny: mountain-building event that affected a broad segment of southern Europe and the Mediterranean region during the middle Tertiary Period (the Tertiary began 66.4 million years ago and ended 1.6 million years ago). The Alpine orogeny produced intense metamorphism of preexisting rocks, crumpling of rock strata, and uplift accompanied by both ... [5 Related Articles]
alpine permafrost: (from the article "permafrost") ...to its widespread occurrence in the Arctic and subarctic areas of the Earth, permafrost also exists at lower latitudes in areas of high elevation. This type of perennially frozen ground is called Alpine permafrost. Although data from high plateaus and mountains are scarce, measurements taken below the active surface layer ...