A B C D E F G H I J K L M N O P Q R S T U V W X Y Z 0-9 pyrargyrite ...  pyrargyrite a sulfosalt mineral, a silver antimony sulfide (Ag3SbS3), that is an important source of silver, ... Pyraustinae (from the article "lepidopteran") ...in feeding sites; subfamily Crambinae contains almost 1,900 species, larvae feeding mainly on roots, grasses, ... pyrazinamide (from the article "tuberculosis") ...the treatment of patients with tuberculosis. As a result, with early drug treatment, surgery is ... pyrazine any of a class of organic compounds of the heterocyclic series characterized by a ring ... [1 Related Articles] pyrazole any of a class of organic compounds of the heterocyclic series characterized by a ring ... [2 Related Articles] pyrazolone (from the article "analgesic") The pyrazolone analgesics (such as phenylbutazone) have effects similar to those of aspirin; they were ... Pyrenean desman (from the article "desman") ...tail of the Russian desman (Desmana moschata) is flattened horizontally and has ... Pyrenees mountain chain of southwestern Europe that consists of flat-topped massifs and folded linear ranges. It ... [8 Related Articles] Pyrenees, Peace of the (Nov. 7, 1659), peace treaty between Louis XIV of France and Philip IV of Spain ... [8 Related Articles] Pyrenees-Atlantiques (from the article "Aquitaine") Tourism is widespread, particularly along the coasts. The Basque coast in Pyrenees-Atlantique has experienced a ... Pyrenees-Orientales (from the article "Languedoc-Roussillon") region of France encompassing the southern departements of Lozere, ... pyrenoid (from the article "algae") ...messenger ribonucleic acid (mRNA) is translated into protein. The ribosomes accurately interpret the genetic code ... Pyrenulales (from the article "fungus") ...the reproductive organs; included in subclass Chaetothyriomycetidae; example genera include Capronia, Ceramothyrium, and Chaetothyrium.Order PyrenulalesParasitic, ... Pyreolophore (from the article "Niepce, Nicephore") In 1807 Niepce and his brother Claude invented an internal-combustion engine, which they called the ... pyrethrin (from the article "Agricultural chemicals") In general, insecticides derived from plants are low in toxicity. Pyrethrins are widely used insecticides ... pyrethrum any of certain plant species of the genus Tanacetum, native to southwestern Asia, whose aromatic ... [2 Related Articles] Pyrex (trademark), a type of glass and glassware that is resistant to heat, chemicals, and electricity. ... [8 Related Articles] Pyrgi (from the article "ancient Italic people") ...Etruscan-Latin bilingual inscriptions, all funerary, have little importance with respect to improving knowledge of Etruscan. ... Pyrgota undata (from the article "June beetle") A natural enemy of the June beetle is the pyrgota fly larva (Pyrgota undata), which ... pyrheliometer (from the article "sunlight") The Eppley pyrheliometer measures the length of time that the surface receives sunlight and the ... pyribole (from the article "amphibole") ...sequences like pyroxenes (single-chain repeats), amphiboles (double-chain repeats), and triple-chain repeats. The latter are intermediate ... pyridazine (from the article "heterocyclic compound") The pyridazine derivative maleic hydrazide is a herbicide, and some pyrazines occur naturally-the antibiotic aspergillic ... pyridine any of a class of organic compounds of the aromatic heterocyclic series characterized by a ... [4 Related Articles] pyridinium chlorochromate (from the article "aldehyde") ...catalyst, but this method is less useful on a smaller scale such as in chemistry ... pyridostigmine (from the article "drug") ...this condition because they enhance the action of acetylcholine and enable transmission to occur in ... pyrilamine (from the article "Bovet, Daniel") ...effect of histamine) is effective in treating allergic reactions. This discovery led to development of ... pyrimethamine (from the article "drug") ...where chloroquine-resistant Plasmodium falciparum is encountered, however, mefloquine or doxycycline are used ... pyrimidine any of a class of organic compounds of the heterocyclic series characterized by a ring ... [7 Related Articles] pyrimidine dimer (from the article "genetic disease, human") Ultraviolet light, when acting on DNA, can lead to covalent linking of adjacent pyrimidine bases. ... pyrite a naturally occurring iron disulfide mineral. The name comes from the Greek word pyr, "fire," ... [10 Related Articles] pyrite structure (from the article "sulfide mineral") ...crystalling in this manner is galena (PbS), the ore mineral of lead. A type of ... pyrobitumen natural, solid hydrocarbon substance, distinguishable from bitumen (q.v.) by being infusible and insoluble. When heated, ... [1 Related Articles] pyrocellulose (from the article "explosive") ...It was first marketed about 1909 and was the most important type of smokeless powder ... Pyrocephalus rubinus (from the article "tyrant flycatcher") ...in black and white. Many have a patch of red or yellow on the crown ... pyrochlore a complex oxide mineral [(Na, Ca)2Nb2O6(OH,F)] composed of niobium, sodium, and calcium that forms brown ... [1 Related Articles] pyroclastic cone (from the article "volcano") Pyroclastic cones (also called cinder cones or scoria cones) such as Cerro Negro in Nicaragua ... pyroclastic flow in a volcanic eruption, a fluidized mixture of hot rock fragments, hot gases, and entrapped ... [8 Related Articles] pyroclastic rock (from the article "igneous rock") ...and dislocation of solid material. In volcanic environments they generally result from explosive activity or ... pyroclastic surge (from the article "pyroclastic flow") ...are generally produced by large eruptions that form calderas. Nuees ardentes deposit ... pyroclastic texture (from the article "igneous rock") Pyroclastic texture results from the explosive fragmentation of volcanic material, including magma (commonly the light, ... Pyrodictium (from the article "bacteria") ...Most striking was the discovery in the mid-1980s of bacteria and archaea in nutrient-rich, extremely ... pyroelectricity development of opposite electrical charges on different parts of a crystal that is subjected to ... [1 Related Articles] pyrogallol an organic compound belonging to the phenol family, used as a photographic film developer and ... [3 Related Articles] pyrogen (from the article "human disease") ...large amounts of tissue have died because of lack of blood supply. Body temperature is ... pyroligneous acid (from the article "wood tar") Hardwood tars are obtained from pyroligneous acid, either as a deposit from the acid or ... pyrolite rock consisting of about three parts peridotite and one part basalt. The name was coined ... pyrolusite common manganese mineral, manganese dioxide (MnO2), that constitutes an important ore. Always formed under highly ... [1 Related Articles] pyrolysis (from the article "carbene") in which R and R' represent two organic groups, which may be the same or ... pyromancy (from the article "augury") ...each with its own specialist jargon and ritual, were atmospheric phenomena (aeromancy), cards (cartomancy), dice ... pyromania impulse-control disorder characterized by the recurrent compulsion to set fires. The term refers only to ... pyrometallurgy (from the article "metallurgy") Two of the most common pyrometallurgical processes, in both extraction and refining, are oxidation and ... pyrometamorphism (from the article "rock") ...produces apparent layering, or banding, because of the segregation of minerals into separate bands. Metamorphic ... pyrometer device for measuring relatively high temperatures, such as are encountered in furnaces. Most pyrometers work ... [3 Related Articles] pyromorphite phosphate mineral, lead chloride phosphate [Pb5(PO4)3Cl], that is a minor ore of lead. It occurs ... Pyronema (from the article "cup fungus") ...which contains about 50 widespread species, produces in summer a cup-shaped fruiting body or mushroomlike ... pyrope magnesium aluminum garnet (Mg3Al2), the transparent form of which is used as a gemstone. Its ... [1 Related Articles] pyrophoric substance (from the article "organometallic compound") ...useful organometallic reagents Li(CH3), Zn(CH3)2, B(CH3)3, and Al2(CH3)6 are spontaneously flammable in air (pyrophoric). Accordingly, ... Pyrophorus (from the article "click beetle") ...American click beetle, grows to 45 mm (over 1 34 in.) long and has two ... pyrophosphatase (from the article "metabolism") In this series of reactions, n indicates the number of hydrocarbon units (&singlehorzbond;CH2&singlehorzbond;) in the ... pyrophosphate (from the article "isoprenoid") The head-to-tail coupling of isosprenoid units in biosynthesis logically follows from expected enzymatic reaction patterns ... pyrophyllite very soft, pale-coloured silicate mineral, hydrated aluminum silicate, Al2(OH)2 Si4O10, that is the main constituent ... [3 Related Articles] Pyrosoma (from the article "bioluminescence") Among other higher animals, the chordate subphylum Tunicata contains luminous forms. The genus Pyrosoma includes ... Pyrosomida (from the article "tunicate") ...forms; atrial aperture directed toward the rear of each zooid; asexual buds form from a ... pyrotechnics (from the article "magnesium processing") Magnesium has been used in military pyrotechnics for many years and has found numerous uses ... pyroxene any of a group of important rock-forming silicate minerals of variable composition, among which calcium-, ... [9 Related Articles] pyroxene quadrilateral (from the article "pyroxene") ...and FeSiO3 (ferrosilite). Since no true pyroxenes exist with calcium contents greater than that of ... pyroxene-hornfels facies (from the article "metamorphic rock") Rocks of the pyroxene-hornfels facies are characteristically formed near larger granitic or gabbroic bodies at ... pyroxenite dark-coloured, intrusive igneous rock that consists chiefly of pyroxene. Pyroxenites are not abundant; they occur ... Pyrrha (from the article "Deucalion") in Greek legend, the Greek equivalent of Noah, the son of Prometheus (the creator of ... pyrrhic foot (from the article "prosody") Some theorists also admit the spondaic foot ('') and pyrrhic foot (˘˘) into their scansions; ... Pyrrhic War (from the article "ancient Rome") Rome spent the 280s BC putting down unrest in northern Italy, but its attention was ... pyrrhiche (from the article "dance, Western") Another dance form that originated in Crete and flourished in Greece was the pyrrhiche, a ... Pyrrhon Of Elis Greek philosopher from whom Pyrrhonism takes its name; he is generally accepted as the father ... [3 Related Articles] Pyrrhonism (from the article "Skepticism") The other major form of ancient Skepticism was Pyrrhonism, apparently developed by medical Skeptics in ... Pyrrhophyta (from the article "algae") ...Cryptomonas, Falcomonas, and Rhinomonas.Division Pyrrophyta (Dinoflagellata)Predominantly ... pyrrhotite iron sulfide mineral (Fe1-xS) in the niccolite group; in it, the ratio of iron to ... [2 Related Articles] Pyrrhus king of Hellenistic Epirus whose costly military successes against Macedonia and Rome gave rise to ... [9 Related Articles] pyrrole any of a class of organic compounds of the heterocyclic series characterized by a ring ... [3 Related Articles] pyrrolidine (from the article "heterocyclic compound") When one of the carbon atoms of cyclopentane is replaced with an atom of nitrogen, ... Pyrus communis (from the article "pear") any of several species of the genus Pyrus, especially Pyrus communis, of the rose family ... pyruvate (from the article "carboxylic acid") Pyruvic acid (in the form of its salt pyruvate) is involved in the normal metabolism ... pyruvate dehydrogenase complex (from the article "metabolism") The oxidation of pyruvate involves the concerted action of several enzymes and coenzymes collectively called ... pyruvate kinase (from the article "metabolism") ...(PEP), water being lost from 2-phosphoglycerate in the process. Phosphoenolpyruvate acts as the second source ... pyruvic acid (from the article "carboxylic acid") Pyruvic acid and acetoacetic acid are the simplest and most important of the alpha-keto and ... Pyryatyn city, east-central Ukraine, on the Uday River. Pyryatyn dates at least from 1155, when it ... pyrylium (from the article "heterocyclic compound") Positively charged ions (cations) of pyrylium and thiopyrylium are the parent six-membered, aromatic, monocyclic oxygen ... Pythagoras Greek philosopher, mathematician, and founder of the Pythagorean brotherhood that, although religious in nature, formulated ... [20 Related Articles] Pythagoras noted Greek sculptor of Rhegium, in Italy (present Reggio di Calabria), a contemporary of Myron ... Pythagorean comma (from the article "comma") ...occurs: . . . A♯, E♯, B♯. This B♯, however, instead of being exactly in ... Pythagorean number (from the article "number game") The study of Pythagorean triples as well as the general theorem of Pythagoras leads to ... Pythagorean scale (from the article "South Asian arts") The two parent scales are complementary and between them supply all the consonances found in ... Pythagorean theorem proposition number 47 from Book I of Euclid's Elements, the well-known geometric ... [10 Related Articles] Pythagorean triple (from the article "mathematics") ...of the terms, the third will usually be irrational, but it is possible to find ... Pythagorean tuning (from the article "musical sound") ...viewpoint all suffer from one of two mutually exclusive faults: either they lack relationships (intervals) ... Pythagoreanism philosophical school and religious brotherhood, believed to have been founded by Pythagoras of Samos, who ... [27 Related Articles] Pytheas navigator, geographer, astronomer, and the first Greek to visit and describe the British Isles and ... [4 Related Articles] Pythia (from the article "oracle") ...the Corinthian Gulf. Traditionally, the oracle first belonged to Mother Earth (Gaea) but later was ... Pythiales (from the article "fungus") ...and behaving as conidia (asexually produced spores); example genera include Albugo, Peronospora, Bremia, and Plasmopara.Order ... Pythian Games in ancient Greece, various athletic and musical competitions held in honour of Apollo, chiefly those ... [4 Related Articles] Pythium (from the article "Pythium") a genus of destructive root-parasitic fungi of the family Pythiaceae (phylum Oomycota, kingdom Chromista), having ... Pythius (from the article "Priene") ...of the most beautiful examples of Greek town planning. The city's remains lie on successive ... Python in Greek mythology, a huge serpent that was killed by the god Apollo at Delphi ... python any of about 28 species of nonvenomous snakes, all but one of which are found ... [1 Related Articles] Python 3 (from the article "tactical weapons system") ...the much-used U.S. Sidewinder is guided to the target by the target's heat emission. One ... Pythonidae (from the article "snake") ...New World tropics, Madagascar, and the southwestern Pacific. Size moderate to very large, 1-8 metres. ... Pyu (from the article "Myanmar") Between the 1st century BCE and the 9th century CE, speakers of Tibeto-Burman languages known ... pyx in Christianity, vessel containing the consecrated bread used in the service of Holy Communion. Although ... [1 Related Articles] Pyxidiophorales (from the article "fungus") ...and penetrates insect exoskeleton to absorb nutrients; spinelike ascoma; example genera include Laboulbenia, Rickia, and ... Pyynikki Open Air Theatre (from the article "Finland") ...1872 with Kaarlo Bergbom as producer and manager; its granite building in Helsinki was built ... Pz. 61 (from the article "tank") The same 105-millimetre gun was adopted for the Pz. 61 and Pz. 68 tanks produced ... Pz. I (from the article "panzer") The Pz. I was a light tank intended as a training vehicle for the new ... Pz. IB (from the article "panzer") ...5.4 tons, had a top road speed of 39 km (24 miles) per hour, and ... Pz. II (from the article "panzer") The Pz. II was larger and more heavily armed and armoured than the Pz. I, ... Pz. III (from the article "tank") Apart from being lightly armoured, the Soviet BT, the equivalent British cruiser tanks, and the ... Pz. IV (from the article "tank") The campaigns of 1939-41, in which armoured forces played such an important role, also intensified ... Pz. V (from the article "tank") ...Pz. IV and Soviet T-34 were rearmed in 1942 with longer-barreled, higher-velocity guns; soon afterward ... Pz. VI (from the article "Porsche, Ferdinand") ...car" and with his son Ferdinand, known as Ferry, was responsible for the initial design ...

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