991 resultados para 380.1
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The analysis of 104 core-catcher samples from Site 603 resulted in a continuous palynological record from the middle Miocene to early Pleistocene. Two palynological zones could be established (Zone 2, below 380 m: high Pinus, Quercus, and Carya values; Zone 1, above 380 m: high Pinus, and Sphagnum values). The marine pollen record was found to reflect the history of the vegetation of the eastern United States, the flora from Zone 2 indicating a warmer climate than that from Zone 1, which depicts a climatic cooling trend. The onset of Western Boundary Undercurrent deposition had no noticeable effect on the pollen distribution in the marine sediments.
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"AFCRL-65-451"
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O livro de Jó pertence à literatura sapiencial de Israel. Seu conteúdo é um grande debate entre sábios. Estes formavam um segmento educado da população: sabiam ler e escrever. A sabedoria era demasiadamente valorizada e concebida como orientação prudente para a vida. O texto 24,1-12 de Jó pertence à parte poética do livro. O poema foi escrito na primeira metade do século V a.C., no período do pós exílio, durante a dominação dos persas. Este império trouxe profundas modificações para a vida do povo em Judá. Apesar da aparente tolerância por parte de seus governantes, eles criaram métodos muito eficazes para alcançar seus objetivos de controle sobre os povos submetidos. Através de um forte aparelho burocrático, fiscal e militar controlavam e garantiam a ordem e o pagamento de tributos. O templo tornou-se o intermediário entre o império e o povo. A economia e a sociedade se estruturaram conforme o regime imposto pelos persas. Essa política econômica e administrativa favorecia o enriquecimento dos setores dominantes, e conseqüentemente o empobrecimento cada vez maior dos camponeses. Os sacerdotes eram os líderes do povo e a teologia da retribuição se fortaleceu muito nessa época. No entanto, a justiça de Deus explicada pela teologia da retribuição deparava-se com o problema do mal e do sofrimento do justo. É a partir da experiência e da observação da realidade que se origina um movimento de resistência à teologia da retribuição. No capítulo 24,1-12, Jó se lança numa contemplação sobre a sociedade dividida entre opressores e oprimidos. Desmonta o funcionamento da sociedade mostrando suas rupturas e conflitos graves. Sua intenção nesse texto é mostrar através da realidade, porque não concorda com as afirmações dos sábios que defendem a teologia da retribuição, sobre o castigo infalível para os ímpios ricos e sobre o sofrimento do pobre como indicação de castigo.(AU)
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Sediment samples from the Ontong-Java Plateau in the Pacific and the 90° east ridge in the Indian Ocean were used to investigate whether shell size and early diagenesis affect d11B of the symbiont-bearing planktonic foraminifer Globigerinoides sacculifer. In pristine shells from both study locations we found a systematic increase of d11B and Mg/Ca with shell size. Shells in the sieve size class 515-865 µm revealed d11B values +2.1 to +2.3 per mil higher than shells in the 250-380 µm class. This pattern is most likely due to differences in symbiont photosynthetic activity and its integrated effect on the pH of the foraminiferal microenvironment. We therefore suggest smaller individuals must live at approximately 50-100 m water depth where ambient light levels are lower. Using the empirical calibration curve for d11B in G. sacculifer, only shells larger than 425 µm reflect surface seawater pH. Partial dissolution of shells derived from deeper sediment cores was determined by shell weight analyses and investigation of the shell surface microstructure by scanning electron microscopy. The d11B in partially dissolved shells is up to 2 per mil lower relative to pristine shells of the same size class. In agreement with a relatively higher weight loss in smaller shells, samples from the Ontong-Java Plateau show a more pronounced dissolution effect than larger shells. On the basis of the primary size effect and potential postdepositional dissolution effects, we recommend the use of shells that are visually pristine and, in the case of G. sacculifer, larger than 500 ?m for paleoreconstructions.
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The composition and abundance of algal pigments provide information on phytoplankton community characteristics such as photoacclimation, overall biomass and taxonomic composition. In particular, pigments play a major role in photoprotection and in the light-driven part of photosynthesis. Most phytoplankton pigments can be measured by high-performance liquid chromatography (HPLC) techniques applied to filtered water samples. This method, as well as other laboratory analyses, is time consuming and therefore limits the number of samples that can be processed in a given time. In order to receive information on phytoplankton pigment composition with a higher temporal and spatial resolution, we have developed a method to assess pigment concentrations from continuous optical measurements. The method applies an empirical orthogonal function (EOF) analysis to remote-sensing reflectance data derived from ship-based hyperspectral underwater radiometry and from multispectral satellite data (using the Medium Resolution Imaging Spectrometer - MERIS - Polymer product developed by Steinmetz et al., 2011, doi:10.1364/OE.19.009783) measured in the Atlantic Ocean. Subsequently we developed multiple linear regression models with measured (collocated) pigment concentrations as the response variable and EOF loadings as predictor variables. The model results show that surface concentrations of a suite of pigments and pigment groups can be well predicted from the ship-based reflectance measurements, even when only a multispectral resolution is chosen (i.e., eight bands, similar to those used by MERIS). Based on the MERIS reflectance data, concentrations of total and monovinyl chlorophyll a and the groups of photoprotective and photosynthetic carotenoids can be predicted with high quality. As a demonstration of the utility of the approach, the fitted model based on satellite reflectance data as input was applied to 1 month of MERIS Polymer data to predict the concentration of those pigment groups for the whole eastern tropical Atlantic area. Bootstrapping explorations of cross-validation error indicate that the method can produce reliable predictions with relatively small data sets (e.g., < 50 collocated values of reflectance and pigment concentration). The method allows for the derivation of time series from continuous reflectance data of various pigment groups at various regions, which can be used to study variability and change of phytoplankton composition and photophysiology.
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Stable isotope and faunal records from the central Red Sea show high-amplitude oscillations for the past 380,000 years. Positive delta18O anomalies indicate periods of significant salt buildup during periods of lowered sea level when water mass exchange with the Arabian Sea was reduced due to a reduced geometry of the Bab el Mandeb Strait. Salinities as high as 53 per mil and 55 per mil are inferred from pteropod and benthic foraminifera delta18O, respectively, for the last glacial maximum. During this period all planktonic foraminifera vanished from this part of the Red Sea. Environmental conditions improved rapidly after 13 ka as salinities decreased due to rising sea level. The foraminiferal fauna started to reappear and was fully reestablished between 9 ka and 8 ka. Spectral analysis of the planktonic delta18O record documents highest variance in the orbital eccentricity, obliquity, and precession bands, indicating a dominant influence of climatically - driven sea level change on environmental conditions in the Red Sea. Variance in the precession band is enhanced compared to the global mean marine climate record (SPECMAP), suggesting an additional influence of the Indian monsoon system on Red Sea climates.
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A series of K-Ar dates from Mt Giluwe volcano is reported and its relevance to the Quaternary history of the volcano is discussed. The period between about 380 000 and 220 000 years BP seems to have been one of major volcanic activity. During the volcanic activity there were periods of ice cover probably of short duration. The oldest evidence of glacial action predates a lava flow dated at between 340 000 and 380 000 years. At about 290 000 years an ice cap of a thickness of at least 100 m covered the summit area and one or a series of subglacial eruption(s) led to the formation of palagonitic breccia. This event was probably associated with a complete melting of the ice since it was followed almost immediately by the eruption of a thick sequence of normal lava flows which range in age from about 289 000 years to about 220 000 years. Subsequent volcanic activity was less significant and no dates are available on this.
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Delta18O and delta13C values for the calcareous dinoflagellate species Orthopithonella? globosa (Fütterer 1984) Lentin and Williams 1985 and Pirumella krasheninnikovii (Bolli 1974) Lentin and Williams 1993 from lates Campanian and earliest Maastrichtian of ODP Hole 690C (Weddell Sea, Antarctic Ocean) have been studied in order to evaluate the species' depth habitat in the water column and their applicability in paleoceanographic studies. The calcareous dinoflagellates show isotopic values comparable to probably shallow-dwelling planktic foraminifera from the same sample in delta18O, but have an offset of about -5 ? to -7? in delta13C. This suggests that calcareous dinoflagellate oxygen isotopes may provide information for paleoceanographic reconstructions of sea-surface water temperatures, whereas their extremely light carbon isotope values are probably due to photosynthetic processes.