988 resultados para 202-1232


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The active plate margin of South America is characterized by a frequent occurrence of large and devastating subduction earthquakes. Here we focus on marine sedimentary records off Southern Chile that are archiving the regional paleoseismic history over the Holocene and Late Pleistocene. The investigated records - Ocean Drilling Program (ODP) Site 1232 and SONNE core 50SL - are located at ~40°S and ~38°S, within the Perú-Chile trench, and are characterized by frequent interbedded strata of turbiditic and hemipelagic origin. On the basis of the sedimentological characteristics and the association with the active margin of Southern Chile, we assume that the turbidites are mainly seismically triggered, and may be considered as paleo-megaearthquake indicators. However, the long-term changes in turbidite recurrence times appear to be strongly influenced by climate and sea level changes as well. During sea level highstands in the Holocene and Marine Isotope Stage (MIS) 5, recurrence times of turbiditic layers are substantially higher, primarily reflecting a climate-induced reduction of sediment availability and enhanced slope stability. In addition, segmented tectonic uplift changes and related drainage inversions likely influenced the postglacial decrease in turbidite frequencies. Glacial turbidite recurrence times (including MIS 2, MIS 3, cold substages of MIS 5, and MIS 6), on the other hand, are within the same order of magnitude as earthquake recurrence times derived from the historical record and other terrestrial paleoseismic archives of the region. Only during these cold stages sediment availability and slope instability were high enough to enable recording of the complete sequence of large earthquakes in Southern Chile. Our data thus suggest that earthquake recurrence times on the order of 100 to 200 years are a persistent feature at least during the last glacial period.

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Deputados progressistas da Assembleia Nacional Constituinte (ANC) se unem para apresentar emendas. Divididos em vinte e nove grupos, avaliam o substitutivo do Relator Bernardo Cabral (PMDB-AM). O Deputado Plínio Arruda Sampaio (PT-SP) considera que, se formarem uma base sólida, os progressistas terão melhores condições de negociar com os outros grupos. O Deputado Vivaldo Barbosa (PDT-RJ) informa dos pontos de consenso do grupo. Na Sessão para discussão de emendas populares, o debate dos direitos dos trabalhadores teve com ponto polêmico a estabilidade no emprego. Luiz Carlos Mandelli, representando o movimento pela livre iniciativa, critica a emenda que dá estabilidade ao empregado. O Deputado Mário Lima (PMDB-BA) afirma que os empresários estão cometendo um equívoco muito grande, pois o trabalhador quando tem estabilidade no emprego produz mais e melhor. Outra emenda popular propõe que o serviço de transporte coletivo seja estatizado. Ela foi defendida por João Bosco, Presidente da CONAN (Confederação Nacional das Associações de Moradores), que considera que cabe às prefeituras a gestão, planejamento e operacionalização do transporte coletivo. A CONAN ainda reivindica 25% do orçamento nacional para a construção de casas populares. Dalva Stella Medeiros (Vice-presidente da CONAN) defende que o poder público deve assumir o direito à moradia popular para todos os cidadãos. Na sessão O Povo Pergunta, cidadã gostaria de saber se os constituintes estão pensando em fazer uma Constituição voltada para pequenos interesses ou para os interesses da grande maioria da população. O Deputado Assis Canuto (PFL-RO) responde que há uma tendência de particularizar a Constituição brasileira, mas cabe a sociedade e aos constituintes fazerem uma Constituição para todos os brasileiros.

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Recent research has shown that the biomass of bacteria in lakes and other water-bodies can attain significant values. The huge production of bacteria is brought about by their great rate of reproduction. In a series of cases their biomass exceeds the biomass of phytoplankton. Therefore in a study of the biological productivity of water bodies it is necessary to calculate the biomass and production not only of the phyto- and zooplankton, but also of bacteria.The authors uses different methods and formulae to to compare the time of one generation of the bacteria.

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The original method, proposed by Yentsch (1957), of determination of chlorophyll directly in the cells, attracts attention by its simplicity. In order to measure the content of chlorophyll by this method, a determined volume of suspension of algae is filtered through a membrane filter. The latter is dried a little, clarified by immersion oil, clamped between two glasses, and spectrophotometrized. Extinction is read off at , wavelengths equal to 670 millimicrons (around the maximum absorption of chlorophyll a in the cell) and 750 millimicrons (correction for non- specific absorption and dispersion of light by particles of the preparation). The method of Yentsch was employed by the authors for determination of chlorophyll-a in samples of phytoplankton. They conclude that in spite of the simplicity and convenience of determination the method must be applied sufficiently carefully. It is more suitable for analysis of cultures of algae, where, non-specific absorption of light is insignificant.

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Eudiaptomus vulgaris Schmeil is the most abundant copepod in Lake Maggiore and forms also, in respect to other entomostraca, the most important element, through its average biomass and because it is fairly numerous throughout the year. Plankton samples collected in a systematic and quantitative way, gave the opportunity to study some aspects of the dynamics of the population of this copepod, in safety in view of the uncertainty which in this kind of study can ensue when samples are taken only at a single station - in consequence of the changes in size of population between different water masses. The results of the biometrical observations are of the population of Eudiaptomus vulgaris is presented.

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利用手征有效场论,通过对核物质中核子传播子的修正,研究了核物质中的△(1232)粒子的有效质量和衰变宽度。发现△(1232)粒子的有效质量随核物质密度的增加而减小,而衰变宽度随核物质密度增加而增加;△(1232)粒子衰变宽度的变化主要取决于核子有效质量及△(1232)粒子有效质量的变化。

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This presentation is about a song, ”Catford Riddim” by the A-Team, a group of grime artists from South London, specifically about how it came to be played, perhaps a bit too loudly, in the back of the 202 bus one January morning on a teenager’s mobile phone. As an illustration of how social networks and technological networks converge, the ”Catford Riddim,” insisting on the music’s own provenance from the SE6 postcode, shows the formation of a local ethnoscape in the global networks of peer-to-peer file sharing and online DIY distribution sites such as MySpace. Contesting the narrative of online social networks as routes to fame, I suggest that on the contrary they illustrate the emergence of local, even insular, ”scenes” of musicians, events and audiences.