990 resultados para 7441-104
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This study investigates the landscape evolution and soil development in the loess area near Regensburg between approximately 6000-2000 yr BP (radiocarbon years), Eastern Bavaria. The focus is on the question how man and climate influenced landscape evolution and what their relative significance was. The theoretical background concerning the factors that controlled prehistoric soil erosion in Middle Europe is summarized with respect to rainfall intensity and distribution, pedogenesis, Pleistocene relief, and prehistoric farming. Colluvial deposits , flood loams, and soils were studied at ten different and representative sites that served as archives of their respective palaeoenvironments. Geomorphological, sedimentological, and pedological methods were applied. According to the findings presented here, there was a high asynchronity of landscape evolution in the investigation area, which was due to prehistoric land-use patterns. Prehistoric land use and settlement caused highly difIerenciated phases of morphodynamic activity and stability in time and space. These are documented at the single catenas ofeach site. In general, Pleistocene relief was substantially lowered. At the same time smaller landforms such as dells and minor asymmetric valleys filled up and strongly transformed. However, there were short phases at many sites, forming short lived linear erosion features ('Runsen'), resulting from exceptional rainfalls. These forms are results of single events without showing regional trends. Generally, the onset of the sedimentation of colluvial deposits took place much earlier (usually 3500 yr BP (radiocarbon) and younger) than the formation of flood loams. Thus, the deposition of flood loams in the Kleine Laaber river valley started mainly as a consequence of iron age farming only at around 2500 yr BP (radiocarbon). A cascade system explains the different ages of colluvial deposits and flood loams: as a result of prehistoric land use, dells and other minor Pleistocene landforms were filled with colluvial sediments. After the filling of these primary sediment traps , eroded material was transported into flood plains, thus forming flood loams. But at the moment we cannot quantify the extent ofprehistoric soil erosion in the investigation area. The three factors that controlled the prehistoric Iandscapc evolution in the Ioess area near Regensburg are as follows: 1. The transformation from a natural to a prehistoric cultural landscape was the most important factor: A landscape with stable relief was changed into a highly morphodynamic one with soil erosion as the dominant process of this change. 2. The sediment traps of the pre-anthropogenic relief determined where the material originated from soil erosion was deposited: either sedimentation took place on the slopes or the filled sediment traps of the slopes rendered flood loam formation possible. Climatic influence of any importance can only be documented as the result of land use in connection with singular and/or statistic events of heavy rainfalls. Without human impact, no significant change in the Holocene landscape would have been possible.
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A 1000-word review of Granta 104 - Fathers : The Men Who Made Us (Allen & Unwin, 2009)
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Contenido: Índice general de autores y materias. Año I, 1946 – Año XXV, 1970
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Mulheres opinam sobre o aborto. Narrador descreve dados da Organização das Nações Unidas - ONU, segundo os quais no Brasil são feitos 10% dos abortos do mundo . Aparecida Shumaher, do Conselho Nacional de Defesa da Mulher, diz que o aborto é questão de responsabilidade ética da mulher, cabendo a ela decidir. Dom Antonio C. de Queiroz, Secretário Geral da Conferência Nacional dos Bispos do Brasil (CNBB), afirma que a igreja é radicalmente contra o aborto. Leonor Nunes de Paiva, da OAB-RJ, defende que a mulher deve ter o direito de interromper a gestação. Diz também que a OAB-RJ entende o aborto como assunto para a legislação ordinária. Deputados da Assembleia Nacional Constituinte (ANC) consideram que o aborto não é matéria constitucional. José Paulo Bisol (PMDB-RS) afirma que o aborto deve ser tratado no Código Penal, não na Constituição. Eunice Michilis (PFL-AM) sugere o aborto apenas nos casos de estupro, gravidez de alto risco e má formação fetal que leve a uma vida vegetativa. Lídice da Mata (PC do B-BA) defende que a descriminalização do aborto refletiria a busca de articular a lei com os acontecimentos da sociedade e que, para evitar o aborto no Brasil, é preciso implementar políticas de planejamento familiar.
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Experiments were carried out by the method of direct effect of the tested substance on increase of biomass (1,2). Daphnia magna was cultured under laboratory conditions.The author concludes that concentrations of aniline from 5000 to 0.1 mg/1 appear acutely lethal. The disturbance of feeding, reproduction, the disorganization of the nervous system, speak of the toxicity of the substance.