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  • radial engine
    ...engines, aircraft could be streamlined to improve speed but with a trade-off in complexity and weight because of the requisite coolant, coolant lines, radiator, and associated pumps. Air-cooled radial designs, in contrast, achieved relative simplicity, reliability, and comparatively light weight at the cost of more air resistance (creating drag) because of their blunt shape. In 1928, the......
  • radial gate (engineering)
    Several forms of gates have been developed. The simplest and oldest form is a vertical-lift gate that, sliding or rolling against guides, can be raised to allow water to flow underneath. Radial, or tainter, gates are similar in principle but are curved in vertical section to better resist water pressure. Tilting gates consist of flaps held by hinges along their lower edges that permit water to......
  • radial keratotomy (surgical procedure)
    surgical procedure to correct myopia (nearsightedness) by reducing the radius of curvature of the cornea and astigmatism (asymmetrical curvature of the cornea). A series of 4 to 8 equally spaced deep cuts are made in the peripheral cornea, leaving the central cornea above the pupil clear. Intraocular pressure then pushes the weakened central cornea outward, f...
  • radial nerve (anatomy)
    The three major nerves of the arm, forearm, and hand are the radial, median, and ulnar. The radial nerve innervates the triceps, anconeus, and brachioradialis muscles, eight extensors of the wrist and digits, and one abductor of the hand; it is also sensory to part of the hand. The median nerve branches in the forearm to serve the palmaris longus, two pronator muscles, four flexor muscles,......
  • radial symmetry (biology)
    In radial symmetry the body has the general form of a short or long cylinder or bowl, with a central axis from which the body parts radiate or along which they are arranged in regular fashion. The main axis is heteropolar—i.e., with unlike ends, one of which bears the mouth and is termed the oral, or anterior, end, and the other of which, called the aboral, or posterior, end, forms.....
  • radial system (plant anatomy)
    The radial system functions primarily in the transport of carbohydrates from the inner bark to the wood; there are some food-storage cells in this system as well, and water movement through the rays is possible. Ray cells interrupt the interconnections of the tracheids or fibres; hence, wood is split more easily along the wood rays....
  • radial tire
    ...that serves to equalize cord tensions. In a bias-ply belted tire, another set of cords overlies the bias-laid ones. This extra set of cords, called a belt, is typically made of fibreglass. A radial-ply belted tire also has a belt running around the entire tire, but the cords are typically made of steel wire-mesh, hence the term “steel-belted radial” tire....
  • radial tuberosity (anatomy)
    ...disk-shaped; its upper concave surface articulates with the humerus (upper arm bone) above, and the side surface articulates with the ulna. On the upper part of the shaft is a rough projection, the radial tuberosity, which receives the biceps tendon. A ridge, the interosseous border, extends the length of the shaft and provides attachment for the interosseous membrane connecting the radius and....
  • radial turbine
    ...by the Swiss mathematician Leonhard Euler and his son Albert in the 1750s found application about 75 years later. In 1826 Jean-Victor Poncelet of France proposed the idea of an inward-flowing radial turbine, the direct precursor of the modern water turbine. This machine had a vertical spindle and a runner with curved blades that was fully enclosed. Water entered radially inward and......
  • radial vein (anatomy)
    ...the radial (thumb) side of the forearm, and the basilic vein, running up the ulnar side of the forearm and receiving blood from the hand, forearm, and arm. The deep veins of the forearm include the radial veins, continuations of deep anastomosing veins of the hand and wrist, and the ulnar veins, both veins following the course of the associated artery. The radial and ulnar veins converge at the...
  • radial velocity (astronomy)
    For objects beyond the immediate neighbourhood of the Sun, only radial velocities can be measured. Initially it is necessary to choose a standard of rest (the reference frame) from which the solar motion is to be calculated. This is usually done by selecting a particular kind of star or a portion of space. To solve for solar motion, two assumptions are made. The first is that the stars that......
  • radial-arm saw (tool)
    Among the machines utilizing a rotating steel disk with peripheral teeth, the radial-arm saw is one of the most useful. The motor-driven blade is manually drawn along a horizontally set shaft or pipe, called a radial arm, that is itself supported by a vertical column attached to a heavy base. The motor-blade unit is free to move back and forth along the arm and can be adjusted to different......
  • radian (mathematics)
    ...complete surface area of a sphere is 4π times the square of its radius, the total solid angle about a point is equal to 4π steradians. Derived from the Greek for solid and the English word radian, a steradian is, in effect, a solid radian; the radian is an SI unit of plane-angle measurement defined as the angle of a circle subtended by an arc equal in length to the circle...
  • radian measure (mathematics)
    ...complete surface area of a sphere is 4π times the square of its radius, the total solid angle about a point is equal to 4π steradians. Derived from the Greek for solid and the English word radian, a steradian is, in effect, a solid radian; the radian is an SI unit of plane-angle measurement defined as the angle of a circle subtended by an arc equal in length to the circle...
  • Radiance of the King, The (work by Laye)
    ...The Dark Child), which draws a poetic, idyllic picture of life in a traditional African town. His most important work, however, is the novel Le Regard du roi (1954; The Radiance of the King), which describes a white man’s quest for personal salvation in the mysterious atmosphere of the West African jungle. It is regarded as among the most imaginativ...
  • radiant (astronomy)
    A meteor shower’s name is usually derived from that of the constellation (or of a star therein) in which the shower’s radiant is situated—i.e., the point in the sky from which perspective makes the parallel meteor tracks seem to originate. Some showers have been named for an associated comet; e.g., the Andromedids were formerly called the Bielids, after Biela’s Comet. T...
  • radiant electric resistance heating system
    Radiant electric resistance heating systems use coils in baseboard units in the rooms, which create convection cycles similar to hot-water radiators, or resistance cables in continuous looped patterns embedded in plaster ceilings. Local temperature control can be much more precise with electric heating, because it is possible to install a thermostatically controlled rheostat to vary the energy......
  • radiant energy (physics)
    Sustained exposure to two forms of radiant energy—namely, UV light and ionizing radiation—is carcinogenic for humans. Repeated and sustained exposure to UV rays emanating from the Sun causes mutations of DNA that ultimately are capable of inducing three different types of skin cancer. As one would expect, the incidence of UV-induced skin cancer is high among farmers, sailors, and......
  • radiant heating
    Another common heating system is the radiant hot-water type. The heat source is applied to a small boiler, in which water is heated and from which it is circulated by an electric pump in insulated copper pipes similar to a domestic hot-water system. The pipes can be connected to cast-iron or finned tube steel radiators within the living spaces. The radiators are placed near the areas of......
  • radiant hot-water heating system
    Another common heating system is the radiant hot-water type. The heat source is applied to a small boiler, in which water is heated and from which it is circulated by an electric pump in insulated copper pipes similar to a domestic hot-water system. The pipes can be connected to cast-iron or finned tube steel radiators within the living spaces. The radiators are placed near the areas of......
  • Radiant Way, The (work by Drabble)
    ...[1988]). The most thoroughgoing of such “Two Nations” panoramas of an England cleft by regional gulfs and gross inequities between rich and poor is Margaret Drabble’s The Radiant Way (1987). With less documentary substantiality, Martin Amis’s novels, angled somewhere between scabrous relish and satiric disgust, offer prose that has the lurid ...
  • Radiata (animal)
    The two coelenterate phyla (Cnidaria and Ctenophora) advanced in complexity beyond the parazoans by developing incipient tissues—groups of cells that are integrally coordinated in the performance of a certain function. For example, coelenterates have well-defined nerve nets, and their contractile fibres, although only specialized parts of more generalized cells, are organized into......
  • radiata pine (tree)
    The beautiful Monterey pine (P. radiata), found sparingly along the California coast, is distinguished by the brilliant colour of its foliage. The Torrey pine (P. torreyana) is found only in a narrow strip along the coast near San Diego, Calif., and on Santa Rosa Island and is the least widely distributed of all known pines....
  • radiate head (plant anatomy)
    The radiate head has disk flowers in the centre surrounded by one or more marginal rows of another kind of flower, the ray flower. The corolla of ray flowers is very irregular. It is tubular at the base but prolonged on the outer side into a generally flat projection, the ray, or ligule. These rays are the petal-like parts, in a comparison of the......
  • radiating texture (mineralogy)
    ...size; lamellar, flat, platelike individuals arranged in layers; bladed, elongated crystals flattened like a knife blade; fibrous, an aggregate of slender fibres, parallel or radiating; acicular, slender, needlelike crystals; radiating, individuals forming starlike or circular groups; globular, radiating individuals forming small spherical or......
  • radiation (physics)
    flow of atomic and subatomic particles and of waves, such as those that characterize heat rays, light rays, and X rays. All matter is constantly bombarded with radiation of both types from cosmic and terrestrial sources. This article delineates the properties and behaviour of radiation and the matter with which it interacts and describes how energy is transferred from radiation to its surroundings...
  • radiation absorbed dose (unit of measurement of radiation)
    the unit of absorbed dose of ionizing radiation, defined in 1962 by the International Commission on Radiological Units and Measurements as equal to the amount of radiation that releases an energy of 100 ergs per gram of matter. One rad is equal approximately to the absorbed dose delivered when soft tissue is exposed to one roentgen of medium-voltage radiation. “Rad” is derived from ...
  • radiation budget (physics)
    The difference between the solar radiation absorbed and the thermal radiation emitted to space determines Earth’s radiation budget. Since there is no appreciable long-term trend in planetary temperature, it may be concluded that this budget is essentially zero on a global long-term average. Latitudinally, it has been found that much more solar radiation is absorbed at low latitudes than at ...
  • radiation chemistry
    When a target is bombarded by a positive ion such as the hydrogen ion H+ or the deuterium ion D+ from a particle accelerator or the alpha particle 4He2+ from nuclear decay, or indeed any high-energy heavy positive ion, the initial effects differ significantly from those of a high-energy electron. This situation results from the fact that, for the same......
  • radiation conductivity (physics)
    The thermal conductivity of oxide glass due to atomic vibrations (the so-called phonon mechanism) does not increase appreciably with temperature. On the other hand, the radiation conductivity (thermal conductivity due to photon transport) increases greatly with temperature. Radiation conductivity is also inversely proportional to the absorption coefficient of a glass for specific photon......
  • Radiation Control for Health and Safety Act (United States legislation)
    ...and purity standards and provided for factory inspection and for legal remedy; the Fair Packaging and Labeling Act, which required honest, informative, and standardized labeling of products; the Radiation Control for Health and Safety Act, which was designed to protect consumers from possible excess radiation generated by X-ray machines, televisions, microwave ovens, and the like; and the......
  • radiation damping (physics)
    In radiation damping, vibrating energy of moving charges, such as electrons, is converted to electromagnetic energy and is emitted in the form of radio waves or infrared or visible light....
  • Radiation Effects Research Foundation (research facility)
    Hiroshima has become a spiritual centre of the peace movement for the banning of nuclear weapons. In 1947 the Atomic Bomb Casualty Commission (since 1975 the Radiation Effects Research Foundation) began to conduct medical and biological research on the effects of radiation in Hiroshima. Five public hospitals and 40 private clinics give free treatment to victims of the bombing. Hiroshima Castle......
  • radiation energy (physics)
    Sustained exposure to two forms of radiant energy—namely, UV light and ionizing radiation—is carcinogenic for humans. Repeated and sustained exposure to UV rays emanating from the Sun causes mutations of DNA that ultimately are capable of inducing three different types of skin cancer. As one would expect, the incidence of UV-induced skin cancer is high among farmers, sailors, and......
  • radiation fog (meteorology)
    ...strong enough to produce turbulent mixing through a considerable depth of the atmosphere. Typical advection fogs extend up to heights of a few hundred metres and sometimes also occur together with radiation fogs....
  • radiation frost (meteorology)
    Two types of frost are recognized: (1) radiation frost, which occurs on clear nights with little or no wind when the outgoing radiation is excessive and the air temperature is not necessarily at the freezing point, and (2) wind, or advection, frost, which occurs at any time, day or night, regardless of cloud cover, when wind moves air in from cold regions. Both types may occur simultaneously.......
  • radiation, gravitational (physics)
    the transmission of variations in the gravitational field as waves. According to general relativity, the curvature of space-time is determined by the distribution of masses, while the motion of masses is determined by the curvature. In consequence, variations of the gravitational field should be transmitted from place to place as waves, just as variations of a...
  • radiation injury (pathology)
    tissue damage or changes caused by exposure to ionizing radiation—namely, gamma rays, X-rays, and such high-energy particles as neutrons, electrons, and positrons. Sources of ionizing radiation may be natural (e.g., radioactive substances such as the element radium or the radioisotopes potassium-40 and carbon-14) or man-made (X-ray ma...
  • radiation laws (physics)
    ...as visible light is, and, thenceforth, the study of thermal radiation became part of the study of radiation in general. In 1859 a physicist in Germany, Gustav Robert Kirchhoff, presented his law of radiation, relating emissive power to absorptivity. An Austrian, Josef Stefan, established the relationship (now called the Stefan-Boltzmann law) between the energy radiated by a blackbody and......
  • radiation laws (physics)
    a mathematical relationship formulated in 1900 by German physicist Max Planck to explain the spectral-energy distribution of radiation emitted by a blackbody (a hypothetical body that completely absorbs all radiant energy falling upon it, reaches some equilibrium temperature, and then reemits that energy as quickly as it absorbs it). Planck assumed that the so...
  • radiation measurement (technology)
    technique for detecting the intensity and characteristics of ionizing radiation, such as alpha, beta, and gamma rays or neutrons, for the purpose of measurement....
  • radiation pressure (physics)
    the pressure on a surface resulting from electromagnetic radiation that impinges on it, which results from the momentum carried by that radiation; radiation pressure is doubled if the radiation is reflected rather than absorbed....
  • radiation processing (industry)
    The large-scale use of such ionizing radiation for modifying and synthesizing materials, known as radiation processing, represents a minor yet significant technology. It involves irradiating materials either with a beam of electrons produced by a high-voltage particle accelerator or with gamma rays emitted by the radioisotope cobalt-16 or, in a few cases, cesium-137. The electrons are generally......
  • radiation sickness
    The signs and symptoms resulting from intensive irradiation of a large portion of the bone marrow or gastrointestinal tract constitute a clinical picture known as radiation sickness, or the acute radiation syndrome. Early manifestations of this condition typically include loss of appetite, nausea, and vomiting within the first few hours after irradiation, followed by a symptom-free interval......
  • radiation sterilization (food processing)
    Food irradiation involves the use of either high-speed electron beams or high-energy radiation with wavelengths smaller than 200 nanometres, or 2000 angstroms (e.g., X rays and gamma rays). These rays contain sufficient energy to break chemical bonds and ionize molecules that lie in their path. The two most common sources of high-energy radiation used in the food industry are cobalt-60......
  • radiation therapy
    use of radiation sources in the treatment or relief of diseases. Radiation therapy almost always makes use of ionizing radiation, deep tissue-penetrating rays, which can physically and chemically react with diseased cells to destroy them. The other forms of radiation, infrared and ultraviolet, can be employed in heat lamps for neuritis and a...
  • radiation-damage dating (paleontology)
    method of age determination that makes use of the damage to crystals and the radiation from radioactive substances caused by storage of energy in electron traps. In the mineral zircon, for example, radiation damage results in a change in colour, the storage of energy in electron traps, and a change in the crystallographic constants of the mineral. Extensive damage may result in a metamict mineral...
  • radiative capture (physics)
    type of nuclear reaction in which a target nucleus absorbs a neutron (uncharged particle), then emits a discrete quantity of electromagnetic energy (gamma-ray photon). The target nucleus and the product nucleus are isotopes, or forms of the same element. Thus phosphorus-31, on undergoing neutron capture, becomes phosphorus-32. The heavier isotope that results may be radioactive, so that neutron c...
  • radiative forcing
    In light of the discussion above of the greenhouse effect, it is apparent that the temperature of Earth’s surface and lower atmosphere may be modified in three ways: (1) through a net increase in the solar radiation entering at the top of Earth’s atmosphere, (2) through a change in the fraction of the radiation reaching the surface, and (3) through a change in the concentration of gr...
  • radiative nuclear encounter (physics)
    At extremely high velocities an electron loses a substantial part of its energy by radiative nuclear encounter. Lost energy is carried by energetic X rays (i.e., bremsstrahlung). The ratio of energy loss by nuclear radiative encounter to collisional energy loss (excitation and ionization) is given approximately by the incident electron energy (E) in units of 1,000,000 eV times......
  • radiator (heat device)
    ...automotive cooling system comprises (1) a series of channels cast into the engine block and cylinder head, surrounding the combustion chambers with circulating liquid to carry away heat; (2) a radiator, consisting of many small tubes equipped with a honeycomb of fins to convect heat rapidly, that receives and cools hot liquid from the engine; (3) a water pump, usually of the centrifugal......
  • radiator hydrometer (measurement device)
    ...instrument is the storage-battery hydrometer, by means of which the specific gravity of the battery liquid can be measured and the condition of the battery determined. Another instrument is the radiator hydrometer, in which the float is calibrated in terms of the freezing point of the radiator solution. Others may be calibrated in terms of “proof ” of an alcohol solution or in......
  • Radić, Stjepan (Croatian political leader)
    peasant leader and advocate of autonomy for Croatia (within a federalized Yugoslavia)....
  • radical (chemistry)
    a chemical reaction initiated by the absorption of energy in the form of light. The consequence of molecules’ absorbing light is the creation of transient excited states whose chemical and physical properties differ greatly from the original molecules. These new chemical species can fall apart, ch...
  • radical (ideologist)
    in politics, one who desires extreme change of part or all of the social order. The word was first used in a political sense in England, and its introduction is generally ascribed to Charles James Fox, who in 1797 declared for a “radical reform” consisting of a drastic expansion of the franchise to the point of universal manhood suffrage. The te...
  • radical (mathematical power)
    ...For instance, if n is any whole number and a is any positive real number, there exists a unique positive real number a, called the nth root of a, whose nth power is a. The root symbol is a conventionalized r for radix, or “root.” The term......
  • Radical Civic Union (political party, Argentina)
    major centre-left political party in Argentina. For much of the 20th century, the Radical Civic Union (UCR) was the primary opposition party to the Peronists, who are represented by the Justicialist Party. The UCR draws significant support from Argentina’s urban middle class....
  • radical critique (economics)
    The question of relevance was at the centre of a “radical critique” of economics that developed along with the student revolts and social movements of the late 1960s. The radical critics declared that economics had become a defense of the status quo and that its practitioners had joined the power elite. The marginal techniques of the economists, ran the argument, were profoundly......
  • Radical Democratic Party (political party, Switzerland)
    centrist political party of Switzerland. With the Christian Democratic People’s Party, the Social Democratic Party, and the Swiss People’s Party, the Radical Democratic Party has governed Switzerland as part of a grand coalition since 1959....
  • Radical Democrats (political party, Chile)
    ...1989 resulted in the removal of the ban on Marxist parties, just one of the amendments to the 1981 constitution that was voted on in a national referendum. Parties under the CPD umbrella include the Christian Democratic Party (Partido Demócrata Cristiano; PDC), one of Chile’s strongest parties; the Social Democratic Radical Party (Partido Radical Social Demócrata; PRSD), wh...
  • radical empiricism (philosophy)
    a theory of knowledge and a metaphysics (theory of Being) advanced by William James, an American pragmatist philosopher and psychologist, based on the pragmatic theory of truth and the principle of pure experience, which contends that the relations between things are at least as real as the things themselves, that their function is real, and that no hidden substrata are necessa...
  • radical feminism
    In contrast to the pragmatic approach taken by liberal feminism, radical feminism aimed to reshape society and restructure its institutions, which they saw as inherently patriarchal. Providing the core theory for modern feminism, radicals argued that women’s subservient role in society was too closely woven into the social fabric to be unraveled without a revolutionary revamping of society....
  • radical geography
    ...it has an associated politics. Many geographers inspired by this approach in the context of the world situation in the 1960s and ’70s were attracted to the politics and adopted the term “radical geography.” Others accepted the power of Marxist-inspired analysis without also agreeing with the associated socialist agenda. From these twin positions, a more broadly based critic...
  • radical hysterectomy (medical procedure)
    ...has spread locally within the tissue, one of two types of hysterectomy may be required. A simple hysterectomy that removes the uterus and cervix will suffice in some cases, whereas in others a radical hysterectomy is necessary to remove the underlying connective tissue (parametrium) and ligaments along with the upper portion of the vagina. If warranted, either of these surgeries may be......
  • Radical Left Party (political party, Denmark)
    ...over the Conservatives, it soon became apparent that it was impossible for the Left Reformers, led by Jens Christian Christensen, to remain united. In 1905 a radical faction broke away to become the Radical Left Party (Radikale Venstre), the most important members of which were Peter Rochegune Munch and Ove Rode....
  • Radical Liberal Party (political party, Germany)
    ...himself to the political designs of Bismarck. After Bismarck’s break with the National Liberals in 1878, however, Forckenbeck joined with much of the party’s left wing to form the secessionist Radical Liberal Party (1881)—a belated and ultimately futile attempt to salvage a compromised liberalism. As his national political career waned, he rose to prominence in the city gov...
  • Radical Liberal Party (political party, Ecuador)
    ...serving two terms (1897–1901 and 1906–11). Much of the administrative structure of the García Moreno era was dismantled. The anticlerical liberals, proclaiming themselves the Radical Liberal Party (Partido Liberal Radical; PLR), gradually removed the church from state education: they instituted civil marriage and burial, proclaimed freedom of religion, permitted divorce,......
  • radical mastectomy (surgery)
    ...only the cancerous mass and a small amount of surrounding tissue; a simple mastectomy removes the entire breast; and a modified radical mastectomy removes the breast along with adjacent lymph nodes. Radical mastectomies involving removal of the breast, underlying muscle, and other tissue are rarely performed. Side effects of surgery may include changes in arm or shoulder mobility, swelling,......
  • radical mastoid operation (surgery)
    ...perforation and by X-ray studies, the bone-eroding cyst can be diagnosed; it can then be removed surgically before it has caused serious harm. This operation is known as a radical mastoid or a modified radical mastoid operation. If during the same procedure the perforation in the tympanic membrane is closed and the ossicular chain repaired, the operation is known as a tympanoplasty, or......
  • Radical Party (political party, Italy)
    ...rule, according to the letter of the 1848 Statuto (constitution). Most moderate Liberals rejected this argument. The campaign for constitutional government was led by Felice Cavallotti and the Radical group in parliament, who in the 1890s strongly denounced bank scandals, tariff protectionism, colonial wars, and the Triple Alliance. The Radicals were a northern, anticlerical, moralistic......
  • Radical Party (political party, Serbia)
    ...Elected to parliament in 1878, he worked, as leader of the opposition, against the authoritarian monarchy in an endeavour to establish a parliamentary democracy. He also helped to found the Radical Party (1881)....
  • Radical Party (political party, Chile)
    ...1989 resulted in the removal of the ban on Marxist parties, just one of the amendments to the 1981 constitution that was voted on in a national referendum. Parties under the CPD umbrella include the Christian Democratic Party (Partido Demócrata Cristiano; PDC), one of Chile’s strongest parties; the Social Democratic Radical Party (Partido Radical Social Demócrata; PRSD), wh...
  • Radical Party (political party, France)
    Daladier was elected to the Chamber of Deputies in 1919 as a member of the Radical Party from Vaucluse département. Daladier quickly made his mark in Paris. In June 1924 he joined the first Herriot government as the minister of colonies. In the turbulent years from 1925 to 1933 he served in several different Cabinets as minister of war, minister of public instruction, or minister......
  • Radical Reconstruction (United States history)
    Victorious in the fall elections, congressional Republicans moved during the 1866–67 session to devise a second, more stringent program for reconstructing the South. After long and acrimonious quarrels between Radical and moderate Republicans, the party leaders finally produced a compromise plan in the First Reconstruction Act of 1867. Expanded and clarified in three supplementary......
  • Radical Republican (United States history)
    during and after the American Civil War, a member of the Republican Party committed to emancipation of the slaves and later to the equal treatment and enfranchisement of the freed blacks....
  • Radical Republican and Radical-Socialist Party (political party, France)
    the oldest of the French political parties, officially founded in 1901 but tracing back to “radical” groups of the 19th century. Traditionally a centrist party without rigid ideology or structure, it was most prominent during the Third Republic (to 1940) and the Fourth Republic (1945–58) but continued to be influential during the Fifth Republic (from 1958)....
  • Radical Republican Party (Spanish history)
    leader of the Spanish Radical Party who headed four governments during the period of centre-right rule (1933–35) in the Second Republic (1931–39)....
  • radical scavenger (chemistry)
    ...free radicals, are highly reactive, producing compounds that cause the off-flavours and off-odours characteristic of oxidative rancidity. Antioxidants that react with the free radicals (called free radical scavengers) can slow the rate of autoxidation. These antioxidants include the naturally occurring tocopherols (vitamin E derivatives) and the synthetic compounds butylated hydroxyanisole......
  • radical theory (sociology)
    ...In particular, these theories generally explain both crime and criminal justice as by-products of capitalism and explore alternative systems that might generate more harmonious social relations. Radical theories tend to view criminal law as an instrument by which the powerful and affluent coerce the poor into patterns of behaviour that preserve the status quo. One such view, the so-called......
  • Radical-Socialist Party (political party, France)
    the oldest of the French political parties, officially founded in 1901 but tracing back to “radical” groups of the 19th century. Traditionally a centrist party without rigid ideology or structure, it was most prominent during the Third Republic (to 1940) and the Fourth Republic (1945–58) but continued to be influential during the Fifth Republic (from 1958)....
  • radicalism (philosophy)
    ...be Blackstone’s “antipathy to reform.” Bentham’s book, written in a clear and concise style different from that of his later works, may be said to mark the beginning of philosophic radicalism. It is also a very good essay on sovereignty. Lord Shelburne (afterward 1st Marquess of Lansdowne), the statesman, read the book and called upon its author in 1781. Bentham beca...
  • radicalism (politics)
    ...it was a nonetheless influential one, affecting a number of the central social scientists of the century, among them Auguste Comte and Tocqueville and later Max Weber and Émile Durkheim. The radicals accepted democracy but only in terms of its extension to all areas of society and its eventual annihilation of any form of authority that did not spring directly from the people as a whole.....
  • Radičević, Branko (Serbian author)
    ...verse an event from Montenegrin history, giving a unique picture of Montenegrin society and reflecting Njegoš’s philosophy of the eternal struggle between good and evil. The lyric verses of Branko Radičević contributed to the break with earlier didactic-objective poetry. Notable Romantic writers included Radičević, Jovan Jovanović (known as Zmaj)...
  • radicidation (radiation)
    ...a dose in the range of 20 to 30 kilograys, necessary to sterilize a food product. Radurization is a dose of 1 to 10 kilograys, that, like pasteurization, is useful for targeting specific pathogens. Radicidation involves doses of less than 1 kilogray for extending shelf life and inhibiting sprouting....
  • radicle (plant anatomy)
    ...the octant group will ultimately produce the seed leaves (cotyledons) and the shoot apex; the other four will form the hypocotyl, the part of the embryo between the cotyledons and the primary root (radicle). The hypophysis will give rise to the radicle and the root cap; the cells of the suspensor will degenerate as the embryo matures....
  • radīf (Iranian music)
    ...rāst-panjgāh. The 12 dastgāhs, with their constituent pieces, make up the radīf, a body of music consisting of 200 to 300 pieces that are memorized and then become the basis of composition and improvisation....
  • Radiguet, Raymond (French author)
    precocious French novelist and poet who wrote at 17 a masterpiece of astonishing insight and stylistic excellence, Le Diable au corps (1923; The Devil in the Flesh), which remains a unique expression of the poetry and perversity of an adolescent boy’s love....
  • Radikale Venstre (political party, Denmark)
    ...over the Conservatives, it soon became apparent that it was impossible for the Left Reformers, led by Jens Christian Christensen, to remain united. In 1905 a radical faction broke away to become the Radical Left Party (Radikale Venstre), the most important members of which were Peter Rochegune Munch and Ove Rode....
  • Radin, Max (American author)
    ...tyranny, satire of the forms, institutions, or personalities of that tyranny is impossible. But, under the more relaxed authoritarianism of an easier going day, remarkable things could be done. Max Radin, a Polish-born American author, noted how satirical journals in Germany before World War I, even in the face of a severe law, vied with each other to see how close they could come to......
  • Radin, Paul (American anthropologist)
    U.S. anthropologist who was influential in advancing a historical model of social structures based on a synthesis of approaches, including social theory, economics, religion, philosophy, and psychology. He pioneered in such important fields of anthropology as culture-personality studies and the use of autobiographical documents. An accomplished linguist, he described a number of North American lan...
  • Radini-Tedeschi, Giacomo (Italian bishop)
    ...that was to lead to the papacy a half century later. Simply because he was a priest of Bergamo, he was asked by the reigning pope, Pius X, to assist in the ceremony of consecration for a new bishop, Giacomo Radini-Tedeschi, who had been appointed to take over the diocese of Bergamo. The new bishop, a member of the Italian nobility, was much taken by the young priest and asked him to serve as hi...
  • radio (broadcasting)
    ...game pitting the best players in the National League against the best of the American League, was played at Comiskey Park in Chicago in 1933. During the 1920s club owners also cautiously embraced radio broadcasting of games. The first major league game broadcast took place in Pittsburgh in 1921, but during that decade only the Chicago Cubs allowed broadcasts of all their games. Many owners......
  • Radio 1 (British broadcasting station)
    ...1973 came some 16 years after the British government had outlawed the previous batch of commercial stations, the so-called pirates, whose staff and style had been recruited and diluted to shape Radio 1, the British Broadcasting Corporation’s new outlet. However, if those who had campaigned for a legitimate commercial radio network in the United Kingdom were expecting the flagship of......
  • Radio Act (United States [1927])
    ...business arrangements that were being made between the leading manufacturers of radio equipment and the leading broadcasters seemed to threaten monopoly. Congress responded by passing the Radio Act of 1927, which, although directed primarily against monopoly, also set up the agency that is now called the Federal Communications Commission (FCC) to allocate wavelengths to broadcasters.......
  • radio altimeter (instrument)
    ...surface or any object such as an airplane. The two main types are the pressure altimeter, or aneroid barometer, which approximates altitude above sea level by measuring atmospheric pressure, and the radio altimeter, which measures absolute altitude (distance above land or water) based on the time required for a radio wave signal to travel from an airplane, a weather balloon, or a spacecraft to....
  • radio antenna (physics)
    Radio waves are used for wireless transmission of sound messages, or information, for communication, as well as for maritime and aircraft navigation. The information is imposed on the electromagnetic carrier wave as amplitude modulation (AM) or as frequency modulation (FM) or in digital form (pulse modulation). Transmission therefore involves not a single-frequency electromagnetic wave but......
  • Radio Astronomical Telescope of the Academy of Sciences (telescope, Zelenchukskaya, Russia)
    The Russian RATAN-600 telescope (RATAN stands for Radio Astronomical Telescope of the Academy of Sciences), located near Zelenchukskaya in the Caucasus Mountains, has 895 reflecting panels, each 7.4 metres (24.3 feet) high, arranged in a ring 576 metres (1,890 feet) in diameter. Using long parabolic cylinders, standing reflectors, or dipole elements, researchers in Australia, France, India,......
  • radio astronomy
    study of celestial bodies by examination of the radio-frequency energy they emit or reflect. Radio waves penetrate much of the gas and dust in space, as well as the clouds of planetary atmospheres, and pass through Earth’s atmosphere with little distortion. Radio astronomers can therefore obtain a much clearer picture of stars and galaxies than is possi...
  • Radio Australia (Australian company)
    ...Public broadcasting is heard on about 70 radio stations. The Special Broadcasting Service has two radio stations and two television stations and is Australia’s only UHF (ultrahigh frequency) outlet. Radio Australia broadcasts in nine different languages to foreign countries, primarily in Asia and in the Pacific. It operates 13 shortwave stations. The Australian National Satellite System ...
  • Radio Authority (British government agency)
    ...broadcasting. It reassigned the regulatory duties of the Independent Broadcasting Authority and Cable Authority to two newly formed bodies, the Independent Television Commission (ITC) and the Radio Authority. The ITC is in charge of licensing and regulating all non-BBC television services, including ITV (renamed Channel 3 in 1993), Channel 4, and cable and satellite services. The Radio......
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