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Acholi ... acre

Acholi ethnolinguistic group of northern Uganda and South Sudan. Numbering more than one million at the turn of the 21st century, they speak a Western Nilotic language of the Eastern Sudanic branch of the Nilo-Saharan family and are culturally and historically related to their traditional enemies, the neighbouring Lango. The Acholi ... achondrite any stony meteorite containing no chondrules (small, roughly spherical objects that formed in the solar nebula). The only exclusions are carbonaceous chondrites of the CI group, which, though they are clearly chondrites, are so heavily altered by water that any evidence for their having contained chondrules is lost. Achondrites, constituting ... achondroplasia genetic disorder characterized by an abnormality in the conversion of cartilage into bone. As a consequence, bones that depend on cartilage models for development, particularly long bones such as the femur and humerus, cannot grow. Achondroplasia is the most common cause of dwarfism. In those afflicted with the disorder, the ... Achterberg, Gerrit Dutch poet whose use of surreal language and imagery influenced a generation of post-World War II poets known as the Experimentalists. His verse, traditional in form, is characterized as romantic and metaphysical. He was a linguistic innovator, often coining new words based on the terminology of science and scholarship. acid any substance that in water solution tastes sour, changes the colour of certain indicators (e.g., reddens blue litmus paper), reacts with some metals (e.g., iron) to liberate hydrogen, reacts with bases to form salts, and promotes certain chemical reactions (acid catalysis). Examples of acids include the inorganic substances known as ... acid dye any bright-coloured synthetic organic compound whose molecule contains two groups of atoms-one acidic, such as a carboxylic group, and one colour-producing, such as an azo or nitro group. Acid dyes are usually applied in the form of their sodium salts, chiefly on wool but also on silk and, to a ... acid halide neutral compound that reacts with water to produce an acid and a hydrogen halide. Acid halides are ordinarily derived from acids or their salts by replacement of hydroxyl groups by halogen atoms. The most important organic acid halides are the chlorides derived from carboxylic acids and from sulfonic acids. The ... acid rain precipitation possessing a pH of about 5.2 or below primarily produced from the emission of sulfur dioxide (SO2) and nitrogen oxides (NOx; the combination of NO and NO2) from human activities, mostly the combustion of fossil fuels. In acid-sensitive landscapes, acid deposition can reduce the pH of surface waters and ... acid-base catalysis acceleration of a chemical reaction by the addition of an acid or a base, the acid or base itself not being consumed in the reaction. The catalytic reaction may be acid-specific (acid catalysis), as in the case of decomposition of the sugar sucrose into glucose and fructose in sulfuric acid; ... acid-base reaction a type of chemical process typified by the exchange of one or more hydrogen ions, H+, between species that may be neutral (molecules, such as water, H2O; or acetic acid, CH3CO2H) or electrically charged (ions, such as ammonium, NH4+; hydroxide, OH; or carbonate, CO32-). It also includes analogous behaviour of ... acidosis abnormally high level of acidity, or low level of alkalinity, in the body fluids, including the blood. There are two primary types of acidosis: respiratory acidosis and metabolic acidosis. Respiratory acidosis results from inadequate excretion of carbon dioxide from the lungs. This may be caused by severe acute or chronic ... Acireale town and episcopal see, eastern Sicily, Italy, on terraces above the Ionian Sea at the foot of Mount Etna, 7 miles (11 km) northeast of Catania. Known as Aquilia by the Romans, the town was called Reale by Philip IV of Spain in 1642. The first part of its name ... Acis in the Greek mythology of Ovid, the son of Faunus (Pan) and the nymph Symaethis. He was a beautiful shepherd of Sicily, the lover of the Nereid Galatea. His rival, Polyphemus the Cyclops, surprised them together and crushed him to pieces with a rock. His blood, gushing forth from beneath, ... Acker, Kathy American novelist whose writing style and subject matter reflect the so-called punk sensibility that emerged in the 1970s. Ackerley, J.R. British novelist, dramatist, poet, and magazine editor known for his eccentricity. Ackerman, Diane American writer whose works often reflect her interest in natural science. Ackermann, Konrad Ernst actor-manager who was a leading figure in the development of German theatre. Ackermann, Louise-Victorine French poet who is best-known for works characterized by a deep sense of pessimism. Ackroyd, Peter British novelist, critic, biographer, and scholar whose technically innovative novels present an unconventional view of history. Acmeist member of a small group of early-20th-century Russian poets reacting against the vagueness and affectations of Symbolism. It was formed by the poets Sergey Gorodetsky and Nikolay S. Gumilyov. They reasserted the poet as craftsman and used language freshly and with intensity. Centred in St. Petersburg, the Acmeists were associated ... acne any inflammatory disease of the sebaceous, or oil, glands of the skin. There are some 50 different types of acne. In common usage, the term acne is frequently used alone to designate acne vulgaris, or common acne, probably the most prevalent of all chronic skin disorders. Acoemeti monks at a series of 5th- to 6th-century Byzantine monasteries who were noted for their choral recitation of the divine office in constant and never interrupted relays. Their first monastery, at Constantinople, was founded in about 400 by St. Alexander Akimetes, who, after long study of the Bible, put into ... acolyte (from Greek akolouthos, "server," "companion," or "follower"), in the Roman Catholic church, a person is installed in a ministry in order to assist the deacon and priest in liturgical celebrations, especially the eucharistic liturgy. The first probable reference to the office dates from the time of Pope Victor I (189-199), ... Acoma Indian pueblo, Valencia county, west-central New Mexico, U.S. The pueblo lies 55 miles (89 km) west-southwest of Albuquerque and is known as the "Sky City." Its inhabitants live in terraced dwellings made of stone and adobe atop a precipitous sandstone butte 357 feet (109 metres) high. They have always engaged ... Aconcagua River river in central Chile. It rises in the northwestern foothills of Mount Aconcagua of the Andes Mountains and flows westward from the Argentine border area to enter the Pacific Ocean north of the city of Vina del Mar after a course of 120 miles (190 km). Much of the Chilean ... Aconcagua, Mount mountain in western Mendoza province, west-central Argentina, on the Chilean border. It is the highest point in the Western Hemisphere. aconite any member of two genera of perennial herbs of the buttercup family (Ranunculaceae): Aconitum, consisting of summer-flowering poisonous plants (see monkshood), and Eranthis, consisting of spring-flowering ornamentals (see winter aconite). Acontius in Greek legend, a beautiful youth of the island of Ceos. During the festival of Artemis at Delos, Acontius saw and loved Cydippe, a girl of a rich and noble family. He wrote on an apple the words "I swear to wed Acontius" and threw it at her feet. She ... Acontius, Jacobus advocate of religious toleration during the Reformation whose revolt took a more extreme form than that of Lutheranism. Acorales the sweet flag order of flowering plants and the most basal lineage among the monocotyledons (monocots), which are characterized by having a single seed leaf. This order contains the single family Acoraceae and one genus (Acorus), which comprises two to four species of plants that resemble the irises. acorn Nut of the oak. Acorns are usually seated in or surrounded by a woody cupule. They mature within one to two seasons, and their appearance varies depending on the species of oak. Acorns provide food for wildlife and are used to fatten swine and poultry. acorn and nut weevil any of approximately 45 species of weevils in the family Curculionidae (order Coleoptera) that have extremely long and slender snouts, which in females can be almost twice the length of the body. The mandibles are located at the tip of the snout. Eggs are deposited in holes chewed in a ... acorn worm any of the soft-bodied invertebrates of the class Enteropneusta, phylum Hemichordata. The front end of these animals is shaped like an acorn, hence their common name. The "acorn" consists of a muscular proboscis and a collar that may be used to burrow into soft sand or mud. The animals vary ... acosmism in philosophy, the view that God is the sole and ultimate reality and that finite objects and events have no independent existence. Acosmism has been equated with pantheism, the belief that everything is God. G.W.F. Hegel coined the word to defend Benedict de Spinoza, who was accused of atheism for ... Acosta, Joaquin Colombian scientist, historian, and statesman who sought to preserve knowledge of his country's early history. Acosta, Jose de Jesuit theologian and missionary to the New World, chiefly known for his Historia natural y moral de las Indias, the earliest survey of the New World and its relation to the Old. His works, missionary and literary, mark the end of the period of the religious and scientific incorporation of ... Acosta, Uriel freethinking rationalist who became an example among Jews of one martyred by the intolerance of his own religious community. He is sometimes cited as a forerunner of the renowned philosopher Benedict de Spinoza. acouchy either of two species of South American rodents that resemble the small tropical-forest-dwelling hoofed animals of Africa and Asia (see royal antelope; chevrotain). Weighing 1 to 1.5 kg (2.2 to 3.3 pounds), acouchys are 30 to 39 cm (12 to 15 inches) long, with a very short (4 to 8 ... acoustic impedance absorption of sound in a medium, equal to the ratio of the sound pressure at a boundary surface to the sound flux (flow velocity of the particles or volume velocity, times area) through the surface. In analogy to electrical circuit theory, pressure corresponds to voltage, volume velocity to current, and ... acoustic interferometer device for measuring the velocity and absorption of sound waves in a gas or liquid. A vibrating crystal creates the waves that are radiated continuously into the fluid medium, striking a movable reflector placed accurately parallel to the crystal source. The waves are then reflected back to the source. The ... acoustic microscope instrument that uses sound waves to produce an enlarged image of a small object. In the early 1940s Soviet physicist Sergey Y. Sokolov proposed the use of ultrasound in a microscope and showed that sound waves with a frequency of 3,000 megahertz (MHz) would have a resolution equal to that ... acoustic neuroma benign tumour occurring anywhere along the vestibulocochlear nerve (also called acoustic nerve), which originates in the ear and serves the organs of equilibrium and hearing. The tumour arises from an overproduction of Schwann cells, the myelin-producing cells that surround the axon of the nerve. Early symptoms include mild unilateral hearing ... acoustic trauma physiological changes in the body caused by sound waves. Sound waves cause variations in pressure, the intensity of which depends upon the range of oscillation, the force exerting the sound, and the distribution of waves. acoustics the science concerned with the production, control, transmission, reception, and effects of sound. The term is derived from the Greek akoustos, meaning "hearing." acoustics, architectural Relationship between sound produced in a space and its listeners, of particular concern in the design of concert halls and auditoriums. Good acoustic design takes into account such issues as reverberation time; sound absorption of the finish materials; echoes; acoustic shadows; sound intimacy, texture, and blend; and external noise. Architectural ... Acquainted with the Night novel by Heinrich Boll, published in German in 1953 as Und sagte kein einziges Wort ("And Said Not a Single Word"). acquired character in biology, modification in structure or function acquired by an organism during its life, caused by environmental factors. With respect to higher organisms, there is no evidence that such changes are transmissible genetically-the view associated with Lamarckism-but, among protozoans and bacteria, certain induced changes are heritable. acquittal in criminal law, acknowledgment by the court of the innocence of the defendant or defendants. Such a judgment may be made by a jury in a trial or by a judge who rules that there is insufficient evidence either for conviction or for further proceedings. An acquittal removes all guilt ... Acrasieae class name for cellular slime molds (division Myxomycophyta). The class contains a single order, Acrasiales, and about a dozen species. The vegetative phase of these slime molds consists of amoeba-like cells (myxamoebas) that group together ultimately to form a fruiting (reproductive) structure. Acre westernmost estado (state) of Brazil. Acre covers the southwesternmost part of Brazil's Hileia (Hylea), the forest zone of the Amazon River basin. Bounded north by Amazonas state, it has western and southern frontiers with Peru and southeastern with Bolivia. The capital is Rio Branco on the Rio Acre in the ... acre unit of land measurement in the British Imperial and United States Customary systems, equal to 43,560 square feet, or 160 square rods. One acre is equivalent to 0.4047 hectares (4,047 square metres). Derived from Middle English aker (from Old English aecer) and akin to Latin ager ("field"), the acre had ...