1001 résultats pour "naturale"
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Zambia - geografía.
Yacimiento de cobre en ZambiaLas ricas vetas minerales del Copperbelt (cinturón del cobre) han tenido una importancia capital en la historia moderna de Zambia. ElCopperbelt se extiende hacia el oeste de Zambia central desde el sur de la República Democrática del Congo y contiene algunos delos mayores yacimientos de cobre de África. La producción en 2004 fue de 426.900 toneladas.Jason Laure/Woodfin Camp and Associates, Inc. La mayor parte del país tiene una vegetación de sabana —praderas salpicad...
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México - (exposé en espagnol).
Guadalajara ; Monterrey , centro de la industria pesada del país; Puebla , una de las más antiguas del país; León , centro agrícola; Ciudad Juárez , centro manufacturero; Tijuana , ciudad fronteriza, Veracruz , puerto principal del país; Acapulco , una ciudad turística de fama mundial... ¡Todas ellas superan el millón de habitantes! México es un país rico en recursos naturales ( plata , antimonio, azufre, petróleo y gas,) y agrícolas (cereales, algodón, arroz, fruta, henequén, chile…). En...
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PHYSIQUE CLASSIQUE
LE MONDE CLASSIQUE
L'IMPORTANCE DE LA SCIENCE GRECQUE
La civilisation et la culture de la Grèce classique sont le berceau de la civilisation et
de la culture occidentales modernes.
2 découverte de propriétés communes à plusieurs substances permettait de chercher quels étaient les éléments simples, les principes matériels dont toutes les choses étaient faites, les principes causals qui les faisaient changer et leurs caractéristiques essentielles communes ou distinctes. Cette tendance à la différenciation et à l’unification est typique de la science grecque, tout comme le fait de s’appuyer sur les différences et les analogies qualitatives. Mais les Grecs cultivèrent aussi l...
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Uruguay (república) - geografía.
territorio nacional, lo que diferencia a la población de Uruguay de la de los demás países de Hispanoamérica. 3.1 Características de la población Uruguay tiene una población (2008) de 3.477.778 habitantes, con una densidad demográfica de 20 hab/km², que se concentra en su mayoría en la costa atlántica. Sólo un7% de la población es rural. 3.2 Ciudades principales Entre las ciudades uruguayas destacan: Montevideo (1.347.888 habitantes), capital del país, principal puerto y centro económico; Pays...
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Aves no voladoras - ciencias de la naturaleza.
Argentina National Tourist Office/Library of Natural Sounds, Cornell Laboratory of Ornithology. Reservados todos los derechos. Las 18 especies de pingüinos se han adaptado a vivir en el medio acuático. Suele decirse que vuelan bajo el agua, su verdadero medio natural. Viven en las áreas frías delhemisferio sur, alimentándose de grandes cantidades de pescado y krill. Tienen una cubierta de plumas densa y una gruesa capa de grasa bajo la piel que los protege tantodel frío como de la sal marina. Su...
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Les sciences politiques et l’Etat moderne
les rapports inter-humains d'un ensemble social. L'Etat moderne se caractérise par l'idée d'une unité territoriale sur laquelle s'exerce une structure juridico-administrative. La société : Il s'agit d'un ensemble d'individus interdépendants organisé et soumis aux règles d'une institution souveraine. Les structures sociales diffèrent généralement en fonction de l'importance du rôle que tient l'individu par rapport au groupe. On appelle pathologie étatique un dysfonctionnement politique lié à un d...
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Arabia Saudí - geografía.
de 78,2 años para las mujeres y de 74 años para los hombres. 4.2 Principales ciudades La capital de Arabia Saudí es Riad (con una población estimada para 2003 de 5.126.000 habitantes). Otras ciudades importantes son: Jiddah (2.801.481 habitantes segúnestimaciones para 2004), ciudad portuaria situada en el mar Rojo; La Meca (1.294.168 habitantes según estimaciones para 2004), el centro más importante deperegrinación musulmana; Medina (918.889 habitantes en 2004), ciudad santa y centro cultural d...
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Etiopía - geografía.
Los recursos de Etiopía son principalmente agrícolas. La meseta es fértil y todavía no está completamente desarrollada. La diversidad de suelos, clima y altitudes permite laobtención de una gran variedad de productos agrícolas. Hay también una gran variedad de depósitos minerales; los principales explotados comercialmente son hierro,cobre, cinc, plomo, potasio, oro y platino. 2.3 Flora y fauna PraderaLas praderas forman una zona ecológica entre los desiertos y los bosques templados e incluyen u...
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Bangladesh - geografía.
Bangladesh caían enfermos por beber agua contaminada extraída de la superficie de los ríos. Varias agencias, como UNICEF, construyeron pozos superficiales por todo elpaís, para proporcionar una fuente de agua más segura. No obstante, en los años noventa, se descubrió que muchos de estos pozos estaban contaminados con arsénico, unveneno de presencia natural en el suelo aluvial de Bangladesh. A lo largo de un periodo de varios años, el arsénico provoca tumores cancerosos en las personas que bebend...
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Helium - chemistry.
the bends. This synthetic atmosphere is also used in medicine to relieve sufferers of respiratory difficulties because helium moves more easily than nitrogen throughconstricted respiratory passages. In surgery, beams of ionized helium from synchrocyclotron sources are proving useful in treating eye tumors, by stabilizing or evenshrinking the tumors. Such beams are also used to shrink blood-vessel malformations in the brains of patients. Helium is used in inert-gas arc welding for light metals, s...
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Embarazo y parto - ciencias de la naturaleza.
La toxemia es otra complicación seria de la última etapa del embarazo. Los síntomas son hipertensión, aumento súbito y cuantioso de peso debido a un edema, llegando aganar de 11 a 13 kilos en un mes, y aparición de proteínas en la orina. Si no se trata, llega a producir ataques de apoplejía y coma que, en casos extremos, puede conducira la muerte del niño. Cuando se diagnostica una toxemia grave, hay que extraer al niño lo antes posible para protegerlo tanto a él como a la madre. Esta situaciónd...
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Le développement technique transforme-t-il les hommes ?
techniques va l'encontre de la naturalité de l'homme ; mais pire surtout, ce progrès est en fait une régression dansles mœurs et dans la morale. En effet, la question qui était mise au concours était : Si le rétablissement dessciences et des art a contribué à épurer les mœurs ? Et la réponse de Rousseau est tout aussi célèbre : « Il seradifficile, je le sens, d'approprier ce que j'ai à dire au tribunal où je comparais. Comment oser blâmer les sciencesdevant une des plus savantes compagn...
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República Checa - geografía.
La población de la República Checa (según estimaciones en 2008) era de 10.220.911 habitantes. Las tasas de crecimiento vegetativo han sido muy bajas desde el comienzode la década de 1980. En 2008 había 8,90 nacidos vivos por cada 1.000 habitantes. El país ha sido una de las regiones más industrializadas de Europa desde la segundamitad del siglo XIX. Aproximadamente el 75% de la población vive en cinco áreas urbanas. La esperanza de vida en 2008 era de 76,6 años. 3.2 Problemas sociales Las relac...
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suédoise, littérature.
Au milieu et à la fin du XIXe siècle, on assiste à une résurgence du réalisme, représenté également par C.J.L. Almquist mais aussi par August Strindberg. Poète prolifique, romancier et essayiste, grand maître du drame naturaliste, l’auteur de Mademoiselle Julie (Fröken Julie, 1888), développe des techniques expressionnistes que l’on retrouve dans sa pièce le Songe (Ett drömspel, 1902). Quelques autres figures se détachent du siècle : Carl Snoilsky, Fredrika Bremer ( Hertha, 1856), Victo...
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Reproducción vegetal - ciencias de la naturaleza.
Ciclo biológico de una gimnosperma (conífera)© Microsoft Corporation. Reservados todos los derechos. Los sacos polínicos contienen las células madres del polen (diploides), que por meiosis forman los granos de polen (haploides). El óvulo está cubierto por tegumentos ycontiene la célula madre del saco embrionario, que sufre una meiosis y forma cuatro células, de las que sólo subsiste una, la cual da lugar al saco embrionario, que es unacélula con ocho núcleos. Tres de estos núcleos se sitúan en u...
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Austria - geografía.
la pesca, sujeta a las restricciones locales correspondientes. Austria posee 18 reservas biogenéticas del Consejo de Europa (CE) y seis reservas de la biosfera concedidas por el programa El Hombre y la Biosfera de la Organización delas Naciones Unidas para la Cultura, la Ciencia y la Educación (UNESCO). Austria, junto con sus países vecinos, ha elaborado una serie de planes para proteger los Alpes yestá intentando hacer desaparecer las fronteras existentes en las zonas protegidas con Alemania y...
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Colorado (river, North America) - Geography.
sometime between AD 1300 and 1400, but their descendants, the Hopi and Pueblo people, continue to farm and irrigate using the river's waters. The first European to visit the river was probably Spanish soldier and explorer Francisco de Ulloa, who explored the mouth of the Colorado in 1539. In 1540 and 1541another Spaniard, Francisco Vásquez de Coronado, traveled through much of the region around the Colorado River. An exploring party from the Coronado expedition,led by Garcia López de Cárdenas,...
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chinoise, philosophie - philosophie.
des peines sévères, dans le but de maîtriser tous les aspects de la société humaine. Ils accordaient plus de prix à la création d’un État fort, dont le monarque serait doté d’un pouvoir illimité, qu’à la préservation de la liberté individuelle. Le légisme s’avéra un instrument efficace pour créer un système économique et militaire puissant. En 221 av. J.-C., au terme d’une politique de conquête audacieuse, les Qin avaient réussi à établir la première dynastie impériale de Chine, empire unifié et...
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Cetáceos - ciencias de la naturaleza.
OrcaLa orca es un gran depredador marino y entre sus presas están: peces, focas, leones marinos y ballenas. Las orcas tienen unaestructura social bien definida que gira en torno a la hembra dominante. Al igual que otros cetáceos con dientes (Odontocetos), lacomunicación entre los individuos está basada en la diversidad de sonidos que emiten estos animales. El silbido que se oye aquípertenece al calderón.Tom McHugh/Photo Researchers, Inc./Library of Natural Sounds, Cornell Laboratory of Ornitholo...
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Portland - geography.
Garden arena, which opened in 1995. In 2000 the Portland Fire, an expansion Women's National Basketball Association team, began play in the Rose Garden as well. VI ECONOMY Portland enjoys a diversified economy. Major manufactured products include paper, transportation equipment, metal products, sportswear, and electronic componentsand equipment. Major corporations headquartered in the metropolitan region include Nike, a leader in the manufacture of sports footwear, in Beaverton; Louisiana-Paci...
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brésilienne, littérature.
symboliste João da Cruz e Sousa, place le thème de la négritude et la douleur qui l’accompagne au cœur de sa problématique. Il est le représentant majeur du courant symboliste au Brésil (les recueils Missal et Broquéis, parus en 1893, sont les seules œuvres éditées de son vivant). 3. 3 Théâtre La production dramaturgique apparaît tardivement au Brésil. Au XIXe siècle, Gonçalves de Magalhães (1811-1882), d’inspiration romantique, signe la première tragédie brésilienne, Antônio José ou le...
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Egipto (república) - geografía.
costa mediterránea. El limo que depositan los afluentes Rosetta (en árabe, Rashid ), Damieta (en árabe, Dumyat ) y otros más hacen del delta la región más fértil del país. Sin embargo, la presa de Asuán ha reducido el caudal del Nilo, causando que las aguas saladas del Mediterráneo penetren en el terreno a lo largo de la costa cercana a ladesembocadura del Nilo. Una serie de cuatro lagos poco profundos y salobres se extienden por la zona del delta en contacto con el mar. Otro gran lago, Birkat...
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Clasificación - ciencias de la naturaleza.
Clasificación de los organismosLa clasificación de los seres vivos es motivo de controversia desde hace mucho tiempo. Arriba: El sistema aristotélico solo reconocíaplantas y animales, que se diferenciaban por el movimiento, el mecanismo de alimentación y la forma de crecimiento. Este sistemaagrupa procariotas, algas y hongos con las plantas, y protozoos móviles capaces de alimentarse con los animales. Centro: Elperfeccionamiento de las técnicas y los materiales de laboratorio puso de manifiesto...
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Antigua and Barbuda - country.
The monetary unit of Antigua and Barbuda is the East Caribbean (EC) dollar of 100 cents (2.70 East Caribbean dollars equal U.S.$1, a fixed rate since 1976). VI ENVIRONMENTAL CONCERNS The growth of the tourist industry has created some environmental problems, including uncontrolled disposal of sewage from hotels on the beach. Hotel developmentalso threatens the Antiguan mangrove trees. Water management is another major area of concern because of limited natural freshwater resources. Coral reefs...
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San Diego - geography.
Qualcomm Stadium is the home of the San Diego Chargers, playing major league football. PETCO Park is the home of the San Diego Padres, playing major leaguebaseball. Major sporting events in the city include a professional golf tournament in February, hydroplane races on Mission Bay in late summer, and the Holiday Bowlpostseason college football game in December. VI ECONOMY The total value of all the goods and services produced in San Diego make it one of the most powerful economies in the worl...
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hispano-américaine, littérature.
révolutionnaires. Cette époque est également marquée par l’émergence de nouveaux centres littéraires tels que Quito (Équateur), Bogotá (Colombie), Caracas (Venezuela) ou Buenos-Aires (Argentine). Ces villes deviennent bientôt, par la richesse de la vie littéraire qui s’y développe, les rivales des capitales des vice-royaumes ; c’est ainsi que les contacts avec le monde non hispanique se multiplient et que la mère patrie voit progressivement chanceler son monopole intellectuel. 4 CONQUÊTE DE L’IN...
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Gato - ciencias de la naturaleza.
2.2 Sentidos La vista del gato está excepcionalmente adaptada a la caza, especialmente de noche. Tiene una excelente visión nocturna, visión periférica muy amplia y una visiónbinocular que le permite calcular distancias con exactitud. La visión diurna del gato no es tan buena como la de los humanos; los gatos ven el movimiento con mucha másfacilidad que el detalle y se cree que sólo pueden ver una gama limitada de colores. El gato tiene un oído extremadamente sensible. Puede oír una amplia esca...
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Zambia - country.
The Livingstone Museum, at Livingstone, has a collection relating to the archaeology and natural history of southern Africa. The Institute for African Studies of theUniversity of Zambia publishes studies relating to central Africa. IV ECONOMY The wealth of Zambia is based largely on mining in the rich copper belt, and downturns in copper prices have severely damaging economic consequences. Someprocessing and manufacturing has been started since independence, and during the 1970s attempts were...
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Himalayas - geography.
result of deforestation the habitat of most of the wildlife has been destroyed. They are now restricted to special protected areas such as the Jaldapara and Kazirangasanctuaries in India ( see Kaziranga National Park) and the Chitawan preserve in Nepal. There are few animals in the Middle Himalayas because of extensive deforestation. In the Great Himalayas musk deer, wild goats, sheep, wolves, and snow leopards are found. The existence of the Abominable Snowman or Yeti has beenreported by highla...
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Metalwork
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INTRODUCTION
Metalwork, in the fine arts, objects of artistic, decorative, and utilitarian value made of one or more kinds of metal--from precious to base--fashioned by either casting,
hammering, or joining or a combination of these techniques.
Early Bronze DiskThis disk with the head of Acheloos, an Etruscan river god, was made of bronze, an alloy of copper and tin, sometime inthe early 5th century bc. It comes from the necropolis of Monte Quaglieri in Tarquinia. Alloys are made by smelting twodifferent metals together.Scala/Art Resource, NY Knowledge of smelting ultimately led to knowledge of mixing different ores together in the smelting process to produce simple alloys. This followed an intermediateperiod, about 3000 BC, when comp...
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Yukon Territory - Geography.
Tourism is the second most important private sector industry in the Yukon. Visitors come to fish, hunt, enjoy the rugged scenery, and see the historic buildings andcreeks associated with the gold rush. Some marten, lynx, muskrat, wolverine, and other fur-bearing animals are still trapped, but the Yukon plays a minor role in Canadian fur production. The Yukon’s manufacturing industries consist almost exclusively of some mineral refining, printing, and sawmilling. Several hydroelectric plants gene...
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Yukon Territory - Canadian History.
Tourism is the second most important private sector industry in the Yukon. Visitors come to fish, hunt, enjoy the rugged scenery, and see the historic buildings andcreeks associated with the gold rush. Some marten, lynx, muskrat, wolverine, and other fur-bearing animals are still trapped, but the Yukon plays a minor role in Canadian fur production. The Yukon’s manufacturing industries consist almost exclusively of some mineral refining, printing, and sawmilling. Several hydroelectric plants gene...
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Prints and Printmaking
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INTRODUCTION
Prints and Printmaking, pictorial images that can be inked onto paper, and the art of creating and reproducing them.
Bewick’s The SkylarkBritish engraver Thomas Bewick’s The Skylark is part of his History of British Birds (2 vols., 1797 and 1804). Bewick wasthe first artist to demonstrate the full potential of wood engraving and is renowned for his fine natural history illustrations.Each illustration shows some of the bird’s natural habitat.Folio Society, London/Bridgeman Art Library, London/New York Historically, the wood engraving was chiefly used for illustrations in magazines and books. It is similar to th...
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Rio de Janeiro (city) - geography.
were coronated; and Our Lady of Candelária Church, thought by some to be the city’s most beautiful church. Another building of interest is the Imperial Palace, located several blocks west of Santos Dumont Airport. Originally constructed as Brazil’s colonial governor’s capitol in1743, it was converted to the royal palace during the city’s period as an imperial capital. It has recently been restored and now houses a cultural center. Otherimpressive 19th-century palaces include Itamaraty and Catete...
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Poliomyelitis.
Physical therapy helps patients with paralytic polio stretch and move affected muscles. This movement minimizes the atrophy, or shrinkage, of affected muscles andlimbs and builds strength. Exercises can also retrain working muscles to compensate for other muscles that have permanently lost the ability to move. Rehabilitativetherapy trains patients to use braces, crutches, and other devices that provide support and aid mobility. V PREVENTION OF POLIO Immunization with polio vaccine is the best w...
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Nuclear Weapons.
Regardless of the method used to attain a supercritical assembly, the chain reaction proceeds for about a millionth of a second, liberating vast amounts of heat energy.The extremely fast release of a very large amount of energy in a relatively small volume causes the temperature to rise to tens of millions of degrees. The resultingrapid expansion and vaporization of the bomb material causes a powerful explosion. VI PRODUCTION OF FISSILE MATERIAL Much experimentation was necessary to make the p...
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Liberia - country.
West Atlantic, or Kwa linguistic groups. D Education Education is free and compulsory for children between the ages of 6 and 15. However, a scarcity of educational facilities means that few Liberians progress beyondprimary school. Almost all children of primary school-age attend school, but the figure drops to 23 percent (1999–2000) for secondary school-age children. Just 60percent of the population was literate in 2005. Higher education is provided by the University of Liberia (1862), in Monro...
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Gardening - biology.
of synthetic and organic fertilizers, see Organic Farming.) Fertilizers usually are sold in packages, on which the percentage by weight of the macronutrients nitrogen (N), phosphorus (P), and potassium (K) are listed on thelabel—always in the order N-P-K. For example, a fertilizer that is labeled 10-5-3 is 10 percent nitrogen, 5 percent phosphorus, and 3 percent potassium. V PLANTING AND TRANSPLANTING Before planting seeds, gardeners prepare, or till, the soil using a variety of methods. Some...
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Soil.
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INTRODUCTION
Soil, the loose material that covers the land surfaces of
an exchange between plants and the atmosphere, as oxygen diffuses into the soil and is used by roots for respiration. In turn, the resulting carbon dioxide diffusesthrough pore spaces and returns to the atmosphere. This exchange is most efficient in soils with a high degree of porosity. For farmers, gardeners, landscapers, andothers with a professional interest in soil health, the process of aeration—making holes in the soil surface to permit the exchange of air—is a crucial activity. Theburrowi...
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Dolphin (aquatic mammal) - biology.
Scientists have observed dolphins displaying three types of caregiving behaviors: standing by, excitement, and supporting. In standing-by behavior, dolphins remain inthe vicinity of an injured or ill companion without offering aid. In excitement behavior, dolphins swim swiftly in circles around an injured dolphin, responding aggressivelytoward threats to the injured animal. For instance, they may bite harpoon lines or charge boats that come too close to the animal. In supporting behavior, one or...
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letteratura italiana
La nuova Italia: orizzonti sociali, politici, ideologici In Italia il raggiungimento dell'unità politica, dopo secoli di dominazione straniera e di particolarismi regionali, impone uno sforzo di unificazione reale, in un paese che presenta situazioni tra loro lontanissime e inconciliabili, dai modi di sviluppo industriale e borghese del Nord alla sopravvivenza di forme di tipo feudale nel Sud. Lo sviluppo del capitalismo italiano si trovò a dover fare i conti con la frantumazione del paes...
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Animal Behavior - biology.
The first motor program analyzed in much detail was the egg-rolling response of geese. When a goose sees an egg outside its nest, it stares at the egg, stretches itsneck until its bill is just on the other side of the egg, and then gently rolls the egg back into the nest. At first glance this seems a thoughtful and intelligent piece ofbehavior, but it is a mechanical motor program; almost any smooth, rounded object (the sign stimulus) will release the response. Furthermore, removal of the egg on...
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Poetry
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INTRODUCTION
Phyllis McGinley
American poet and author Phyllis McGinley composed light, witty verse, much of which deals with family life.
repetition of certain lines and the rhyming of certain lines. The Provençal sestina features a set of six words that end lines (end-words), repeated in a dizzyingly complexpattern. The range of effects created by the poetic line varies tremendously depending on its length, its patterns of repetition, and whether the sentence stops at the end of theline (end-stopped) or carries over the end of the line (enjambed). Many of the earliest examples of Old English poetry feature an accentual line with...
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Abolitionist Movement.
The American Revolution (1775-1783) and the French Revolution (1789-1799), widely seen as revolutions by citizens against oppressive rulers, transformed thisEnlightenment assertion into a call for universal liberty and freedom. The successful slave revolt that began in the French colony of Saint-Domingue in 1791 was part of this revolutionary age. Led by François Dominique ToussaintLouverture, black rebels overthrew the colonial government, ended slavery in the colony, and in 1804 established th...
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Abolitionist Movement - U.
The American Revolution (1775-1783) and the French Revolution (1789-1799), widely seen as revolutions by citizens against oppressive rulers, transformed thisEnlightenment assertion into a call for universal liberty and freedom. The successful slave revolt that began in the French colony of Saint-Domingue in 1791 was part of this revolutionary age. Led by François Dominique ToussaintLouverture, black rebels overthrew the colonial government, ended slavery in the colony, and in 1804 established th...
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Ecuador - country.
F Natural Resources Ecuador’s main mineral wealth is in petroleum. Other mineral resources of the country include gold, silver, copper, lead, and zinc. Forests cover 38.3 percent of thecountry. G Plants and Animals Along the northern part of the Ecuador coast, and within the inner portion of the southern coast, tropical jungles abound. In some places the jungles extend up theslopes of the Andes as wet, mossy forests. Dense forests cover both flanks of the Cordilleras, as well as the Oriente, u...
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Mexico City - geography.
The park houses some of Mexico's most important public buildings, including Chapultepec Castle. Construction of the castle began in 1783. Positioned on the park’shighest elevation, the castle functioned as a fortress during colonial times. It once served as the presidential residence and now houses the National Museum of History,which includes murals by 20th-century Mexican painter Juan O'Gorman. Los Pinos, the official residence and working offices of the president, is also on the grounds, buti...
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Spanish Empire.
Spain’s royal government quickly imposed its own officials, first to collect taxes and then to administer the colony. Its goal was to assert royal control over both settlersand indigenous peoples. In Spain the government established a House of Trade to supervise colonial affairs and to oversee, license, and tax all trade and commerce. Asthe royal government asserted more authority over colonial activities, Columbus lost effective power, and was eventually replaced by other colonial governors. Wi...
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Spanish Empire .
Spain’s royal government quickly imposed its own officials, first to collect taxes and then to administer the colony. Its goal was to assert royal control over both settlersand indigenous peoples. In Spain the government established a House of Trade to supervise colonial affairs and to oversee, license, and tax all trade and commerce. Asthe royal government asserted more authority over colonial activities, Columbus lost effective power, and was eventually replaced by other colonial governors. Wi...
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Manhattan Project - U.
other possible uses of nuclear energy, such as using uranium to operate large power plants or, perhaps, as power sources for ships or submarines. Then Nazi Germanyinvaded Poland on September 1, 1939, and Europe plunged into war. The scientists realized that any plans to build large-scale nuclear power plants would have to waituntil the war was over. Two weeks after the invasion of Poland, Hitler made a radio speech in which he threatened Britain with “a weapon against which there is no defense.”...