A-Z Browse

  • parakīyārati (Hinduism)
    The Vaiṣṇava-Sahajiyās elevated parakīyā-rati (literally, “the love of a man for a woman who legally belongs to another”) above svakīyā-rati (conjugal love) as the more intense of the two. Parakīyārati, it was said, was felt without consideration for the conventions of society or for personal g...
  • Parakou (Benin)
    town and administrative capital of Borgou province, central Benin (formerly Dahomey), West Africa. It is the terminus of the so-called Benin–Niger Railway, which was originally planned to extend to the Niger River. The railway runs northward from Cotonou, Benin’s major port and commercial centre on the Gulf of Guinea, to Parakou, whence goods must be transported by road to the navig...
  • Pārakrama Paṇḍita (Sinhalese writer)
    ...but it had a life of its own in Sinhalese. The most important, and possibly the oldest, of such chronicles is the Thūpavaṃsaya (“Chronicle of the Great Stupa”), by Pārakrama Paṇḍita. Subsequent chronicles, or genealogies of places, comprise the history of all of the major Buddhist monuments. Several chronicles were also inspired by the......
  • Parakrama Samudra (irrigation system, Sri Lanka)
    ...works became a regular preoccupation of kings. Reservoirs and canals studded the northern and north-central plains, tapping every source of water. Among the most noteworthy was the magnificent Parakrama Samudra in Polonnaruwa, the crowning glory of Parakramabahu I’s reign, with a storage area of more than 5,000 acres (2,000 hectares) for the irrigation of 18,000 acres (7,300 hectares)....
  • Parākramabāhu I (king of Sri Lanka)
    Sinhalese king of Ceylon (1153–86) who united the island under one rule, reformed Buddhist practices, and sent successful expeditionary forces to India and Burma....
  • Parakramabahu II (king of Sri Lanka)
    ...(all part of the Dambadeniya dynasty) ruled from there. They made occasional successful raids into Rajarata to attack the Kalinga and Tamil rulers but did not attempt to reoccupy Polonnaruwa. Under Parakramabahu II (reigned 1236–70) the Dambadeniya kingdom achieved great power; it was able to expel the Kalingas from the island with Pandyan help and to repel an invasion by Malays from......
  • Parakramabahu the Great (king of Sri Lanka)
    Sinhalese king of Ceylon (1153–86) who united the island under one rule, reformed Buddhist practices, and sent successful expeditionary forces to India and Burma....
  • Parakramabahu VI (king of Sri Lanka)
    Sinhalese kingdom that flourished in Ceylon (Sri Lanka) during the 15th century. Its king, Parākramabāhu VI (1412–67), was the last native sovereign to unify all of Ceylon under one rule. By 1450, Parākramabāhu VI had, with his conquest of the kingdom of Jaffna in northern Ceylon, unified all of Ceylon. By 1477, however, 10 years after the death of......
  • Parakumbasirita (Sinhalese poem)
    Of a different style are panegyrics and war poems, the earliest of which is the Parakumbasirita (“History of Parakramabahu VI,” king in Jayavardhanapura from 1410 to 1468). Again reminiscent of the mainland and the religious tradition are the plentiful eulogies of the Buddha. Popular, too, was didactic verse, among the most notable of which is the Kusajātaka, 687...
  • paraldehyde (chemical compound)
    colourless liquid of disagreeable taste and pungent odour used in medicine as a sedative–hypnotic drug and in chemistry in the manufacture of organic chemicals. When administered as a medicine, it is largely excreted by the lungs and gives an unpleasant odour to the breath. It is most useful for recalcitrant cases and is an older drug for treatment of acute alcoholic dementia....
  • Paralelle des anciens et des modernes (work by Perrault)
    ...there was a certain rebellion against this rigidity, perhaps in recognition of the fact that the rule of theory inhibited creativity and especially because it had become authoritarian. In Paralelle des anciens et des modernes (1688–97; “Parallels Between the Ancients and the Moderns”), the French critic Charles Perrault argues for the superiority of......
  • Paralepididae (fish)
    any of about 50 species of marine fishes of the family Paralepididae, found almost worldwide in deep waters. Barracudinas are long-bodied, slender fishes with large eyes, pointed snouts, and large mouths provided with both small and larger, fanglike teeth. Barracudinas grow to about 60 cm (2 feet) long. They are not often seen but are sometimes attracted to bright lights at the surface. They are n...
  • paraliageosyncline (geology)
    ...more common of these are the taphrogeosyncline, a depressed block of the Earth’s crust that is bounded by one or more high-angle faults and that serves as a site of sediment accumulation, and the paraliageosyncline, a deep geosyncline that passes into coastal plains along continental margins. ...
  • Paralichthys dentatus (fish)
    In the families Bothidae and Paralichthyidae, which together contain more than 240 species, the better-known flounders include the summer flounder (Paralichthys dentatus), an American Atlantic food fish growing to about 90 cm (35 inches); the peacock flounder (Bothus lunatus), a tropical American Atlantic species attractively marked with many pale blue spots and rings; and the......
  • Paralipomena of Jeremiah (Pseudepigrapha)
    In the last chapter of the Greek text of the Paralipomena (additional stories) of Jeremiah, there is a hint of the Christian part of the Ascension of Isaiah: the people stoned Jeremiah to death because he, like Isaiah before him, prophesied the coming of Christ. In a parallel legend (preserved in Arabic), both the violent death of Jeremiah and the Christian motif are......
  • Paralipomenon I and II (Old Testament)
    two Old Testament books that were originally part of a larger work that included the books of Ezra and Nehemiah. These three (Ezra and Nehemiah were one book in the Jewish canon) were the final books of the Hebrew Bible. Together they survey Israel’s history from Adam to the activity of Ezra and Nehemiah in the period after the Babylonian Exile (6th century bc). The uniformity...
  • Paralithodes camtschaticus (crustacean)
    (Paralithodes camtschaticus), marine crustacean of the order Decapoda, class Malacostraca. This edible crab is found in the shallow waters off Japan, along the coast of Alaska, and in the Bering Sea. The king crab is one of the largest crabs, weighing 5 kg (11 pounds) or more. Its size and tasty flesh make it a valued food, and large numbers are commercially fished each year....
  • parallax (optics)
    in astronomy, the difference in direction of a celestial object as seen by an observer from two widely separated points. The measurement of parallax is used directly to find the distance of the body from the Earth (geocentric parallax) and from the Sun (heliocentric parallax). The two positions of the observer and the position of the object form a triangle; if the base line between the two observ...
  • parallel (geography)
    imaginary line extending around the Earth parallel to the equator; it is used to indicate latitude. The 38th parallel, for example, has a latitude of 38° N or 38° S. See latitude and longitude....
  • parallel bars (sports)
    gymnastics apparatus invented in the early 19th century by the German Friedrich Jahn, usually considered the father of gymnastics. It is especially useful in improving upper-body strength. The two bars, made of wood, are oval in cross section, 5 cm (2 inches) thick, 3.5 metres (11.5 feet) long, 2 metres (6.5 feet) high, and 42 cm (16.5 inches) apart. Height and width of the bars...
  • parallel bus (computer science)
    ...integrated drive electronics (IDE) and enhanced integrated drive electronics (EIDE) are common interfaces, or buses, for magnetic disk drives. A bus (also known as a port) can be either serial or parallel, depending on whether the data path carries one bit at a time (serial) or many at once (parallel). Serial connections, which use relatively few wires, are generally simpler and slower than......
  • parallel circuit (electronics)
    ...carries current that pulsates back and forth many times each second, as in most household circuits. A series circuit comprises a path along which the whole current flows through each component. A parallel circuit comprises branches so that the current divides and only part of it flows through any branch. The voltage, or potential difference, across each branch of a parallel circuit is the......
  • parallel computer (computing)
    One way to reduce the time required for accurate rendering is to use parallel processing, so that in ray shading, for example, multiple rays can be traced at once. Another technique, pipelined parallelism, takes advantage of the fact that graphics processing can be broken into stages—constructing polygons or Bezier surfaces, eliminating hidden surfaces, shading, rasterization, and so on.......
  • parallel cousin (anthropology)
    ...siblings are patrilateral cousins, and those of a mother’s siblings are matrilateral cousins; the children of a mother’s sister or of a father’s brother are parallel cousins (sometimes called ortho-cousins); and the children of a father’s sister or of a mother’s brother are cross-cousins....
  • parallel displacement (mathematics)
    ...In 1917, inspired by Albert Einstein’s general theory of relativity, Levi-Civita made his most important contribution to this branch of mathematics, the introduction of the concept of parallel displacement in general curved spaces. This concept immediately found many applications and in relativity is the basis of the unified representation of electromagnetic and gravitational......
  • parallel distributed processing (psychological model)
    Another name for connectionism is parallel distributed processing, which emphasizes two important features. First, a large number of relatively simple processors—the neurons—operate in parallel. Second, neural networks store information in a distributed fashion, with each individual connection participating in the storage of many different items of information. The......
  • parallel distributed-information processor (computer science)
    ...human brain as an information processor of the parallel type. The cognitive sciences, the interdisciplinary field that focuses on the study of the human mind, have contributed to the development of neurocomputers, a new class of parallel, distributed-information processors that mimic the functioning of the human brain, including its capabilities for self-organization and learning. So-called......
  • parallel drain system (agriculture)
    The field drains of a surface system may be arranged in many patterns. Probably the two most widely used are parallel drains and random drains. Parallel drains are channels running parallel to one another at a uniform spacing of a few to several hundred feet apart, depending on the soil and the slope of the land. Random drains are channels that run to any low areas in the field. The parallel......
  • parallel evolution (biology)
    the evolution of geographically separated groups in such a way that they show morphological resemblances. A notable example is the similarity shown by the marsupial mammals of Australia to the placental mammals elsewhere. Through the courses of their evolution they have come to remarkably similar forms, so much so that the marsupials are often named for their placental counterparts (e.g., ...
  • parallel lines (geometry)
    A theorem from Euclid’s Elements (c. 300 bc) states that if a line is drawn through a triangle such that it is parallel to one side (see the figure), then the line will divide the other two sides proportionately; that is, the ratio of segments on each side will be equal. This is known as the proportional segments theorem, or the fundament...
  • Parallel Lives (work by Plutarch)
    Plutarch’s popularity rests primarily on his Parallel Lives. These, dedicated to Trajan’s friend Sosius Senecio, who is mentioned in the lives “Demosthenes,” “Theseus,” and “Dion,” were designed to encourage mutual respect between Greeks and Romans. By exhibiting noble deeds and characters, they were also to provide model patterns of b...
  • parallel magnetic circuit (physics)
    ...unbroken loop. All the lines together constitute the total flux. If the flux is divided, so that part of it is confined to a portion of the device and part to another, the magnetic circuit is called parallel. If all the flux is confined to a single closed loop, as in a ring-shaped electromagnet, the circuit is called a series magnetic circuit....
  • parallel motion (technology)
    ...engine, in which the piston pushed as well as pulled. The engine required a new method of rigidly connecting the piston to the beam. He solved this problem in 1784 with his invention of the parallel motion—an arrangement of connected rods that guided the piston rod in a perpendicular motion—which he described as “one of the most ingenious, simple pieces of mechanism I......
  • parallel ohmmeter (instrument)
    ...for measuring electrical resistance, which is expressed in ohms. In the simplest ohmmeters, the resistance to be measured may be connected to the instrument in parallel or in series. If in parallel (parallel ohmmeter), the instrument will draw more current as resistance increases. If in series (series ohmmeter), current will decrease as resistance rises. Ratio meters measure the ratio of the......
  • parallel perspective (art)
    Another kind of system—parallel perspective combined with a viewpoint from above—is traditional in Chinese painting. When buildings rather than natural contours are painted and it is necessary to show the parallel horizontal lines of the construction, parallel lines are drawn parallel instead of converging, as in linear perspective. Often foliage is used to crop these lines before......
  • parallel polarization (physics)
    ...increased. Some unusual alloys exhibit yields up to 100 times greater than normal (i.e., about 0.1). Normally the yield depends also on polarization and angle of incidence of the radiation. Parallel polarization (polarization in the plane of incidence) gives higher yield than does perpendicular polarization, in some instances by almost 10 times....
  • parallel postulate (geometry)
    When Euclid presented his axiomatic treatment of geometry, one of his assumptions, his fifth postulate, appeared to be less obvious or fundamental than the others. As it is now conventionally formulated, it asserts that there is exactly one parallel to a given line through a given point. Attempts to derive this from Euclid’s other axioms did not succeed, and, at the beginning of the 19th......
  • parallel processing (computing)
    One way to reduce the time required for accurate rendering is to use parallel processing, so that in ray shading, for example, multiple rays can be traced at once. Another technique, pipelined parallelism, takes advantage of the fact that graphics processing can be broken into stages—constructing polygons or Bezier surfaces, eliminating hidden surfaces, shading, rasterization, and so on.......
  • parallel runway (airport)
    An increase in operational capacity under VFR is possible with the use of a close parallel runway configuration. Most very large airports must be assured of adequate capacity even under IFR conditions, and this can be achieved by separating the parallel runways by a minimum of 1,035 metres (3,400 feet), which was the distance approved by the International Civil Aviation Organization on Nov. 9,......
  • parallel straightedge (drawing instrument)
    ...value in the preparation of such drawings. Equipment has been invented to facilitate the performance of the manual tasks. Most widely known are the T square, triangle, protractor, and compass; the parallel straightedge is an alternative to the T square. The drafting machine, introduced about 1930, allows a straightedge to be moved while maintaining any desired angle between it and the edge of.....
  • parallel transport (mathematics)
    ...In 1917, inspired by Albert Einstein’s general theory of relativity, Levi-Civita made his most important contribution to this branch of mathematics, the introduction of the concept of parallel displacement in general curved spaces. This concept immediately found many applications and in relativity is the basis of the unified representation of electromagnetic and gravitational......
  • parallel turn (skiing)
    ...the prototype for modern skis. He developed basic skiing turns, which became standard as the stem turn, the Christiania, and the stem Christiania. In 1850 he had been the first skier to perform parallel turns. In 1868 Nordheim and some friends skied 322 km (200 miles) from Telemark to Christiania (later Oslo), where he made a jump of 18 m (59 feet). He is credited with developing in 1870......
  • parallel-flow heat exchanger
    ...In the diagram the cold fluid flows through the inner tube and the warm fluid in the same direction through the annular space between the outer and the inner tube. This flow arrangement is called parallel flow. Heat is transferred from the warm fluid through the wall of the inner tube (the so-called heating surface) to the cold fluid. A heat exchanger can also be operated in counterflow, in......
  • parallel-plate capacitor (electronics)
    A useful device for storing electrical energy consists of two conductors in close proximity and insulated from each other. A simple example of such a storage device is the parallel-plate capacitor. If positive charges with total charge +Q are deposited on one of the conductors and an equal amount of negative charge −Q is deposited on the second conductor, the capacitor is......
  • Parallèlement (work by Verlaine)
    ...review La Revue blanche. A new phase in book illustration was inaugurated with Bonnard’s decoration of the pages in Paul Verlaine’s book of Symbolist poetry, Parallèlement, published by Vollard in 1900. He undertook the illustration of other books during the 1900s....
  • parallelism (figure of speech)
    in rhetoric, component of literary style in both prose and poetry, in which coordinate ideas are arranged in phrases, sentences, and paragraphs that balance one element with another of equal importance and similar wording. The repetition of sounds, meanings, and structures serves to order, emphasize, and point out relations. In its simplest form parallelism consists of single words that have a sl...
  • parallelism (biblical interpretation)
    Parallelism is a prominent figure in Hebrew poetry as well as in most literatures of the ancient Middle East. The Old Testament and New Testament, reflecting the influence of Hebrew poetry, contain many striking examples of parallelism, as in the following lines from the Psalms: “but they flattered him with their mouths; they lied to him with their tongues” (Psalms 78:36); “we...
  • parallelism, psychophysical
    in the philosophy of mind, a theory that excludes all causal interaction between mind and body inasmuch as it seems inconceivable that two substances as radically different in nature could influence one another in any way. Mental and physical phenomena are seen as two series of perfectly correlated events; the usual analogy is that of two synchronized clocks that keep perfect time. Thus, for para...
  • parallelistic song (poetry)
    ...existence of an indigenous popular oral poetry in sung verse during the preceding centuries. A composition attributed to Alfonso X, a 13th-century king of Castile and Leon, is the earliest extant parallelistic song—a brief, repetitive lyrical poem marked by a wistful sadness that runs throughout Portuguese literature. Of the many later poems that survive, most belong to the major......
  • parallelogram (geometry)
    ...or subtracted. For example, to add or subtract vectors v and w graphically (see the diagram), move each to the origin and complete the parallelogram formed by the two vectors; v + w is then one diagonal vector of the parallelogram, and ......
  • parallels (geography)
    imaginary line extending around the Earth parallel to the equator; it is used to indicate latitude. The 38th parallel, for example, has a latitude of 38° N or 38° S. See latitude and longitude....
  • parallels of latitude (geography)
    imaginary line extending around the Earth parallel to the equator; it is used to indicate latitude. The 38th parallel, for example, has a latitude of 38° N or 38° S. See latitude and longitude....
  • Paralycopodites (extinct plant genus)
    ...plants that lived during the Carboniferous Period (360 to 300 million years ago). Lepidodendron and its relatives—Lepidophloios, Bothrodendron, and Paralycopodites—were related to modern club mosses. They grew up to 40 metres (130 feet) in height and 2 metres (about 7 feet) in diameter. During their juvenile stages, these plants grew....
  • paralysis (pathology)
    loss or impairment of voluntary muscular movement caused by structural abnormalities of nervous or muscular tissue or by metabolic disturbances in neuromuscular function. Paralysis can affect the legs and lower part of the body (paraplegia) or both arms and both legs (quadriplegia). Sometimes the muscles of the lower face, arm, and leg on only one side of the body are involved (...
  • paralysis agitans (pathology)
    ...by the British physician James Parkinson in his Essay on the Shaking Palsy. Various types of the disorder are now recognized, but the disease described by Parkinson, called Parkinson disease, is the most common form. Parkinson disease is also called primary parkinsonism, paralysis agitans, or idiopathic parkinsonism. The onset of Parkinson disease typically occurs at.....
  • paralysis, infantile (pathology)
    acute viral infectious disease of the nervous system that usually begins with general symptoms such as fever, headache, nausea, fatigue, and muscle pains and spasms and is sometimes followed by a more serious and permanent paralysis of muscles in one or more limbs, the throat, or the chest. More than half of all cases of polio occur in children...
  • paralytic polio (pathology)
    In most cases paralytic polio strikes the limb muscles, particularly the legs. Paralysis does not always involve the limbs, however. The abdominal muscles or the muscles of the back may be paralyzed, affecting posture. The neck muscles may become weak, so that the head cannot be raised. Paralysis of the face muscles may cause twisting of the mouth or drooping eyelids. In some types of spinal......
  • paralytic poliomyelitis (pathology)
    In most cases paralytic polio strikes the limb muscles, particularly the legs. Paralysis does not always involve the limbs, however. The abdominal muscles or the muscles of the back may be paralyzed, affecting posture. The neck muscles may become weak, so that the head cannot be raised. Paralysis of the face muscles may cause twisting of the mouth or drooping eyelids. In some types of spinal......
  • paralytic shellfish poison (biology)
    ...which are thereby rendered unsafe or poisonous for human consumption. The dinoflagellates (class Dinophyceae) are the most notorious producers of toxins. Paralytic shellfish poisoning is caused by saxitoxin or any of at least 12 related compounds. Saxitoxin is probably the most toxic compound known; it is 100,000 times more toxic than cocaine. Saxitoxin and saxitoxin-like compounds are nerve......
  • paralytic shellfish poisoning (pathology)
    ...have been Gonyaulax catenella along the Pacific coast of North America and G. tamarensis along the eastern coast of North America. Intoxications from these organisms are known as paralytic shellfish poisoning. The symptoms, which begin with a tingling or burning sensation, then numbness of the lips, gums, tongue, and face, gradually spread. Gastrointestinal upset may be......
  • Param Sant Ji Maharaj (Indian spiritual leader)
    The Sant Mat tradition was established by Param Sant Ji Maharaj (1818–78), who taught surat shabd yoga, the yoga of the “Sound Current.” He believed that the universe was created by a series of sound waves emanating from the transcendent Divine and that, as the Divine Sound Current descended into the realm of matter, it became imprisoned. Humans, according to.....
  • paramagnetism (physics)
    kind of magnetism characteristic of materials weakly attracted by a strong magnet, named and extensively investigated by the British scientist Michael Faraday beginning in 1845. Most elements and some compounds are paramagnetic. Strong paramagnetism (not to be confused with the ferromagnetism of the elements iron, cobalt, nickel, and other alloys) is exhibited by compounds containing iron, pallad...
  • paramahamsa (Hinduism)
    Among dashanami sannyasis, the highest stage of achievement is recognized by the title paramahamsa (“great swan”). This honorific is usually given only after a probation of at least 12 years as an ascetic and only to those who have achieved full self-knowledge......
  • Paramahamsa Sabha (Hindu organization)
    The immediate predecessor of the Prarthana Samaj in Bombay was the Paramahamsa Sabha, a secret society formed in 1849 for discussion, the singing of hymns, and the sharing of a communal meal prepared by a low-caste cook. In 1864 Keshab Chunder Sen, founder of the Bharatvarshiya Brahmo Samaj, visited Bombay, and the interest he evoked there bore fruit several months later when the new......
  • Paramanuchit (Siamese religious leader and author)
    prince-patriarch of the Siamese Buddhist church who was a prolific writer on patriotic and moralistic themes in verse and prose. He became abbot of Watphra Jetubon and was later created krom somdec-phra Paramanujit, prince-patriarch of the church....
  • Paramanujita Jinorasa (Siamese religious leader and author)
    prince-patriarch of the Siamese Buddhist church who was a prolific writer on patriotic and moralistic themes in verse and prose. He became abbot of Watphra Jetubon and was later created krom somdec-phra Paramanujit, prince-patriarch of the church....
  • Paramāra (people)
    Adjoining the kingdom of the Caulukyas was that of the Paramaras in Malava, with minor branches in the territories just to the north (Mount Abu, Banswara, Cungarpur, and Bhinmal). The Paramaras emerged as feudatories of the Rashtrakutas and rose to eminence during the reign of Bhoja. An attack by the Caulukyas weakened the Paramaras in 1143. Although the dynasty was later re-established, it......
  • Paramaribo (Suriname)
    largest city, capital, and chief port of Suriname. It lies 9 miles (15 km) from the Atlantic Ocean on the Suriname River. It originated as an Indian village that became a French settlement (c. 1640) and was later the site of an English colony planted in 1651 by Lord Willoughby of Parham. In 1667 Paramaribo was one of the settlements ceded to the Dutch under the Treaty of ...
  • Paramārtha (Buddhist monk)
    The Yogacara school was represented in China primarily by the Faxiang (or Dharmalaksana; also Weishi) school, called Hossō in Japan. Paramartha, an Indian missionary-teacher, introduced the basic Yogacara teachings to China in the 6th century, and his translation of the Mahayana-samparigraha-shastra provided the foundation for the Silun school. Silun was succeeded.....
  • paramārtha-satya (Buddhist concept)
    ...samsara and nirvana cannot be sustained. As developed by later philosophers, such as Jnanagarbha in the 8th century, the doctrine of the Two Truths, absolute truth (paramarthasatya) and conventional truth (samvritisatya), resolves the apparent conflict by stating that ultimately things do not exist as such,......
  • paramarthasatya (Buddhist concept)
    ...samsara and nirvana cannot be sustained. As developed by later philosophers, such as Jnanagarbha in the 8th century, the doctrine of the Two Truths, absolute truth (paramarthasatya) and conventional truth (samvritisatya), resolves the apparent conflict by stating that ultimately things do not exist as such,......
  • Paramattha Mañjūsā (work by Dhammapāla)
    ...Paramattha dipani (Pali: “Elucidation of the True Meaning”), a commentary on several books of the Khuddaka nikaya. In the Paramattha manjusa (Pali: “Jewel Box of the True Meaning”), a commentary on Buddhaghosa’s Visuddhimagga, Dhammapala quotes a verse from the Hindu script...
  • Paramecium (biology)
    genus of free-living protozoans of the holotrichous order Hymenostomatida. There are at least eight well-defined species; all can be cultivated easily in the laboratory. Although they vary in size, most Paramecium species are about the size of the period at the end of this sentence. The basic shape varies, depending on the species: P. caudatum is elongated and gracefully streamlined...
  • Paramecium aurelia (biology)
    gram-negative symbiotic bacterium found in the cytoplasm of certain strains of the protozoan Paramecium aurelia. These bacteria, when released into the surroundings, change to P particles that secrete a poison (paramecin) that kills other sensitive strains of P. aurelia. The possession of kappa organisms is determined genetically. The kappa bearers, called killers, are immune to......
  • Paramecium bursaria (biology)
    ...Tetraselmis, Carteria) that lives within the bodies of various freshwater protozoans and invertebrates. Zoochlorellae often colour their hosts green (e.g., green hydra and green Paramecium bursaria). As symbionts, zoochlorellae use carbon dioxide and nitrogenous and phosphorous wastes and, in illuminated conditions, provide oxygen and useful nutrients to their hosts.......
  • Paramecium caudatum (biology)
    ...free-living protozoans of the holotrichous order Hymenostomatida. There are at least eight well-defined species; all can be cultivated easily in the laboratory. Although they vary in size, most Paramecium species are about the size of the period at the end of this sentence. The basic shape varies, depending on the species: P. caudatum is elongated and gracefully streamlined and......
  • paramedical personnel
    health-care workers who provide clinical services to patients under the supervision of a physician. The term generally encompasses nurses, therapists, technicians, and other ancillary personnel involved in medical care but is frequently applied specifically to highly trained persons who share with physicians the direct responsibility for patient care. This category includes nurse practiti...
  • paramedics
    health-care workers who provide clinical services to patients under the supervision of a physician. The term generally encompasses nurses, therapists, technicians, and other ancillary personnel involved in medical care but is frequently applied specifically to highly trained persons who share with physicians the direct responsibility for patient care. This category includes nurse practiti...
  • paramesonephric duct (anatomy)
    ...a duct of the epididymis, a ductus deferens, an ejaculatory duct, and a seminal vesicle. In females the mesonephric ducts are largely suppressed. The other two ducts, called the paramesonephric or müllerian ducts, persist, in females, to develop into the fallopian tubes, the uterus, and part of the vagina; in males they are largely suppressed. Differentiation also occurs in the primitive...
  • Paramesvara (Malay ruler)
    ...the great entrepôt of Malacca (Melaka) and its dependencies and provided Malay history with its golden age, still evoked in idiom and institutions. The founder and first ruler of Malacca, Paramesvara (d. 1424, Malacca), a Sumatran prince who had fled his native Palembang under Javanese attack, established himself briefly in Tumasik (now Singapore) and settled in Malacca in the last......
  • Paramesvara (king of Khmer empire)
    founder of the Khmer, or Cambodian, Empire and outstanding member of the series of rulers of the Angkor period (802–1431). Among Jayavarman II’s accomplishments were the deification of the Cambodian monarchy, the establishment of the devarāja cult as the official state religion, and the reunification of the old kingdom of Chenla, which he expanded and formed into the Kh...
  • parameter (mathematics and statistics)
    in mathematics, a variable for which the range of possible values identifies a collection of distinct cases in a problem. Any equation expressed in terms of parameters is a parametric equation. The general equation of a straight line in slope-intercept form, y = mx + b, in which m and b are parameters, is an example of a parametric equ...
  • parameterized post-Newtonian theory (physics)
    ...well by observation.) In a whole class of more-general theories, these and other effects not predicted by simple Newtonian theory are characterized by free parameters; such formulations are called parameterized post-Newtonian (PPN) theories. There is now considerable experimental and observational evidence for limits to the parameters. So far, no deviation from general relativity has been......
  • parameters, variation of (mathematics)
    general method for finding a particular solution of a differential equation by replacing the constants in the solution of a related (homogeneous) equation by functions and determining these functions so that the original differential equation will be satisfied....
  • paramilitary (monastic group)
    Paramilitary, or quasi-monastic, associations are another type of monastic group. Whereas most Christian orders of this sort also fulfilled medical or healing commitments, non-Christian monastic orders of this type did not cater to the sick. The Knights Templars, a Crusading order founded in the Holy Land in the early 12th century, became the most prestigious and later the most defamed......
  • Paramillo, Mount (mountain, Colombia)
    ...than 5,000 feet (1,500 metres) between Cali and Buenaventura on the Pacific coast mark the lowest depressions in the range. Elsewhere the crest is much higher, reaching 12,992 feet (3,960 metres) at Mount Paramillo in the department of Antioquia. From there the Cordillera Occidental fingers north into the three distinct serranías of Abibe, San Jerónimo, and Ayapel, forested...
  • Paramirim (river, Brazil)
    ...In this stretch the river receives its main left-bank tributaries—the Paracatu, Urucuia, Corrente, and Grande rivers—and its main right-bank tributaries—the Verde Grande, Paramirim, and Jacaré....
  • pāramitā (Buddhism)
    in Mahāyāna (“Greater Vehicle”) Buddhism, any of the perfections, or transcendental virtues, practiced by bodhisattvas (“Buddhas-to-be”) in advanced stages of their path toward enlightenment. The six virtues are generosity (dāna-pāramitā); morality (śīla-pāramit...
  • paramnesia (psychology)
    The term paramnesia was introduced by a German psychiatrist, Emil Kraepelin, in 1886 to denote errors of memory. He distinguished three main varieties; one he called simple memory deceptions, as when one remembers as genuine those events imagined or hallucinated in fantasy or dream. This is not uncommon among confused and amnesic people and also occurs in paranoid states. Kraepelin also wrote......
  • paramnesia tout court (psychology)
    The déjà vu experience has aroused considerable interest and is occasionally felt by most people, especially in youth or when they are fatigued. It has also found its way into literature, having been well described by, among other creative writers, Shelley, Dickens, Hawthorne, Tolstoy, and Proust. The curious sense of extreme familiarity may be limited to a single sensory system,......
  • páramo (biome)
    The distinctive páramo biome of the equatorial high mountains reaches its greatest development in Colombia. This alpine vegetation is characterized by tussock grasses, cushion plants, and the treelike frailejón (Espeletia), a curious-looking hairy-leafed genus of some 50 different species. Fire-resistant and adapted to low temperatures and high humidity, it......
  • paramorph (mineral)
    ...(see also epitaxy). Alteration pseudomorphs may be formed in several ways: from a change in internal crystal structure without a change in chemical composition (these pseudomorphs are called paramorphs; e.g., aragonite becomes calcite, and brookite becomes rutile); by the loss of an ingredient from the original compound (e.g., cuprite loses oxygen to form copper); by the......
  • Paramount Communications Inc. (American corporation)
    American corporation that was acquired by Viacom Inc. in 1994....
  • Paramount Pictures Corporation (American corporation)
    one of the first and most successful of the Hollywood motion-picture studios. ...
  • paramylum (biology)
    ...cellulose wall, have a flexible pellicle (envelope) that allows changes in shape. Food, absorbed directly through the cell surface or produced by photosynthesis, is stored as a complex carbohydrate (paramylum). Reproduction is asexual, by longitudinal cell division; sexual reproduction is unknown. Species of Euglena live in fresh and brackish water rich in organic matter. Some species......
  • paramyosin (protein)
    ...smooth, except for cardiac muscle, which is involuntary but striated. Obliquely striated muscle is found only in some invertebrate groups (the nematodes, annelids, and mollusks) and has the protein paramyosin in the thick filaments as well as myosin....
  • Paramyxoviridae (virus family)
    ...hemagglutinin (major antigen) and neuraminidase. The only viruses in this family are influenza viruses of 3 distinct antigenic types (A, B, and C).Family ParamyxoviridaeEnveloped virions varying in size from 150 to 300 nm in diameter with a helical nucleocapsid containing a single negative-strand nonsegmented RNA and an.....
  • paramyxovirus (genus of viruses)
    ...nonsegmented RNA and an endogenous RNA polymerase. The lipoprotein envelope contains 2 glycoprotein spikes designated hemagglutinin-neuraminidase (HN) and fusion factor (F). The major genus is paramyxovirus and is composed of human parainfluenza viruses and mumps virus, as well as Newcastle disease virus of poultry. The genus morbillivirus contains the agents that cause measles in humans,......
  • paramyxovirus (virus family)
    ...hemagglutinin (major antigen) and neuraminidase. The only viruses in this family are influenza viruses of 3 distinct antigenic types (A, B, and C).Family ParamyxoviridaeEnveloped virions varying in size from 150 to 300 nm in diameter with a helical nucleocapsid containing a single negative-strand nonsegmented RNA and an.....
  • Paran (desert, Middle East)
    This section apparently combines various traditions of how the Israelites came into Palestine, and J, E (or JE), and P sources have been discerned in these chapters. The traditional “40 years” in the wilderness (38 or 39, according to critical calculations) were spent mostly in the wilderness of Paran, with a short stay in the oasis of Kadesh, according to P; while, according to J,.....

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