542 resultados para 997


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Carbon isotope and benthic foraminiferal data from Blake Outer Ridge, a sediment drift in the western North Atlantic (Ocean Drilling Program Sites 994 and 997, water depth ~ 2800 m), document variability in the relative volume of Southern Component (SCW) and Northern Component Waters (NCW) over the last 7 Ma. SCW was dominant before ~5.0 Ma, at ~3.6-2.4 Ma, and 1.2-0.8 Ma, whereas NCW dominated in the warm early Pliocene (5.0-3.6 Ma), and at 2.4-1.2 Ma. The relative volume of NCW and SCW fluctuated strongly over the last 0.8 Ma, with strong glacial-interglacial variability. The intensity of the Western Boundary Undercurrent was positively correlated to the relative volume of NCW. Values of Total Organic Carbon (TOC) were > 1.5% in sediments older than ~ 3.8 Ma, and not correlated to high primary productivity indicators, thus may reflect lateral transport of organic matter. TOC values decreased during the intensification of the Northern Hemisphere Glaciation (NHG, 3.8-1.8 Ma). Benthic foraminiferal assemblages underwent major changes when the sites were dominantly under SCW (3.6-2.4 and 1.2-0.8 Ma), coeval with the 'Last Global Extinction' of elongate, cylindrical deep-sea benthic foraminifera, which has been linked to cooling, increased ventilation and changes in the efficiency of the biological pump. These benthic foraminiferal turnovers were neither directly associated with changes in dominant bottom water mass nor with changes in productivity, but occurred during global cooling and increased ventilation of deep waters associated with the intensification of the NHG.

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Holes 603C and 604 of DSDP Leg 93 were drilled on the western Atlantic continental rise at water depths of 4633 m and 2364 m, respectively. In Hole 603C, a nearly continuous, undisturbed, and complete section of Pliocene and lower Pleistocene sediments was recovered by hydraulic piston coring; in Hole 604, a section of uppermost Miocene to Pleistocene sediments was incompletely recovered by rotary coring. In order to reconstruct the Pliocene and Pleistocene history of isotopic variations, 139 oxygen and carbon isotope values were determined for planktonic and monospecific benthic foraminifer samples from these holes. Large parts of the Pleistocene history could not, however, be documented because sample intervals were large and sediments at Site 604 were redeposited. Time correlation is based on magnetostratigraphic (Hole 603C) and micropaleontologic (Hole 603C, Site 604) interpretation. Stable isotope analyses were carried out on the planktonic foraminiferal species Globigerinoides ruber, G. obliquus, and Globorotalia inflata from Hole 603C (48 analyses) and from Site 604 (48 analyses); at Site 604, the benthic foraminifer Uvigerina peregrina (43 analyses) was also studied through the section. Age calibration for Hole 603C is based on the magnetostratigraphy of Canninga et al. (1987; doi:10.2973/dsdp.proc.93.130.1987), which uses the time scale of Lowrie and Alvarez (1981).

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Deep-sea benthic foraminiferal faunas were studied from Sites 608 (depth 3534 m, 42°50'N, 23°05'W) and 610 (depth 2427 m, 53°13'N, 18°53'W). The sampling interval corresponded to 0.1 to 0.5 m.y. at Site 608 and in the sections of Site 610 from which core recovery was continuous. First and last appearances of benthic foraminiferal taxa are generally not coeval at the two sites, although the faunal patterns are similar and many species occur at both sites. Major periods of changes in the benthic faunas, as indicated by the numbers of first and last appearances and changes in relative abundances, occurred in the early Miocene (19.2-17 Ma), the middle Miocene (15.5-13.5 Ma), the late Miocene (7-5.5 Ma), and the Pliocene-Pleistocene (3.5-0.7 Ma). A period of minor changes in the middle to late Miocene (10-9 Ma) was recognized at Site 608 only. These periods of faunal changes can be correlated with periods of paleoceanographic changes: there was a period of sluggish circulation in the northeastern North Atlantic from 19.2 to 17 Ma, and the deep waters of the oceans probably cooled between 15.5 and 13.5 Ma, as indicated by an increase in delta18O values in benthic foraminiferal tests. The period between 10 and 9 Ma was probably characterized by relatively vigorous bottom-water circulation in the northeastern Atlantic, as indicated by the presence of a widespread reflector. The faunal change at 7 to 5.5 Ma corresponds in time with a worldwide change in delta13C values, and with the Messinian closing of the Mediterranean. The last and largest faunal changes correspond in time with the onset and intensification of Northern Hemisphere glaciation.

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Concentrations of organic and inorganic nitrogen have been measured on Leg 80 sediments. The inorganic nitrogen content is relatively constant, 0.02-0.03 wt.%. Because most of the inorganic nitrogen occurs as NH3 or (NH4)+ fixed on clays, clay-poor sediments have lower inorganic nitrogen contents. Organic nitrogen content depends upon both the type and the quantity of organic matter present. In Leg 80 sediments, woody kerogens contain much less organic nitrogen than do kerogens of algal origin. Furthermore, pelagic samples of low organic carbon content have less organic nitrogen than predicted, because of loss during diagenesis. DSDP shipboard analytical procedures do not distinguish between organic and inorganic nitrogen. Great caution must therefore be exercised in interpreting C/N ratios.

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Incluye relación de un viage desde Constantinopla a Alepo. Id. de un Concilio Nacional de los Maronitas en 1736. Monte Libano, China, Japón, Indias Orientales.

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Paged continuously; v. 1: 1 p. l., 996 p.; v. 2: 2 p. l., [997]-2252 p.

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"Purdue Research Foundation. Fellowship no.997. Project Ae-24. This research was supported by the United States Army, through the office of Ordnance Research, under Contract no.DA33-008 ORD-888."

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A simple method for the measurement of the active leflunomide metabolite A77 1726 in human plasma by HPLC is presented. The sample workup was simple, using acetonitrile for protein precipitation. Chromatographic separation of A77 1726 and the internal standard, alpha-phenylcinnamic acid, was achieved using a C-18 column with UV detection at 305 nm. The assay displayed reproducible linearity for A77 1726 with determination coefficients (r(2)) > 0.997 over the concentration range 0.5-60.0 mug/ml. The reproducibility (%CV) for intra- and inter-day assays of spiked controls was

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We report here a validated method for the quantification of a new immunosuppressant drug FTY720, using HPLC-tandem mass spectrometry. Whole blood samples (500 mu l) were subjected to liquid-liquid extraction, in the presence of an internal standard (Y-32919). Mass spectrometric detection was by selected reaction monitoring with an atmospheric pressure chemical ionization source in positive ionization mode (FTY720: m/z 308.3 -> 255.3). The assay was linear from 0.2 to 25 mu g/l (r(2) > 0.997, n = 5). The inter- and intra-day analytical recovery and imprecision for quality control samples (0.5, 7 and 15 mu g/l) were 95.8-103.2 and < 5.5%, respectively. At the lower limit of quantification (0.2 mu g/l) the interand intra-day analytical recovery was 99.0-102.8% with imprecision of < 7.6% (n = 5). The assay had a mean relative recovery of 100.5 +/- 5.8% (n = 15). Extracted samples were stable for 16 h. IFTY720 quality control samples were stable at room temperature for 16 h at 4 degrees C for at least 8 days and when taken through at least three freeze-thaw cycles. In conclusion, the method described displays analytical performance characteristics that are suitable for pharmacokinetic studies in humans. (c) 2006 Elsevier B.V. All rights reserved.

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As linguagens artísticas são de grande importância para o desenvolvimento pleno de todo ser humano. No ensino básico, as crianças estão em processo de desenvolvimento da intelectualidade e da criatividade no assim chamado período de alfabetização. Neste sentido, esta pesquisa tem como objetivo investigar como o ensino de Arte está inserido neste processo, nas séries iniciais no ensino fundamental em uma escola estadual do município de Diadema (SP), onde há a atuação direta do professor especialista em artes nas séries iniciais da educação básica. O quadro teórico transcorre pela importância de uma arte humanizadora e abordagem triangular em Ana Mae Barbosa (1999) e da experiência estética em Vygotsky (2010) e Dewey (2010) no desenvolvimento da criança durante o processo de alfabetização. O diálogo com os autores perpassa uma reflexão sobre as expectativas que o docente tem das práticas pedagógicas e de sua possível inter-relação com as necessidades de aprendizagem dos alunos entendidas em um sentido que não separa o desenvolvimento cognitivo do desenvolvimento artístico. Para efetuar este trabalho, utilizou-se a metodologia de pesquisa qualitativa fazendo uso de entrevistas com quatro professoras alfabetizadoras e quatro professoras de Arte, questionário de perfil, 08 questões semidiretivas para cada professora. Para aprofundamento fez-se uso de Grupo Focal. As conclusões indicam que a falta de apoio da família, a diversidade de informações que o aluno adquire fora do ambiente escolar, as diferentes fases de aprendizagem dos alunos na mesma classe e a falta de material e espaço físico para o ensino de Arte, ainda faz parte dos desafios da profissão de professor no que diz respeito ás dificuldades encontradas para efetuar sua prática. Ainda há a necessidade de entrosamento entre os profissionais e os conteúdos no caminho das fronteiras entre arte educação e alfabetização, como por exemplo, idéia de que o professor alfabetizador faz de si de forma negativa, como o rigoroso, da aula chata e de que professor e aula de arte são libertadores , ou a aula da folga dos conteúdos mais sérios ainda é pulsante na representação de alguns professores de alfabetização. A falta de atualização dos professores de Arte, a não abertura para articular com suas próprias linguagens ainda são questões a refletir no que diz respeito à formação deste profissional, bem como as tensões sobre as relações no ambiente pedagógico em face às variadas mudanças que ocorrem na trajetória da educação.

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The work reported in this thesis was carried out to contribute to the knowledge of the effects of substrate water availability or water activity (a ) on fungal growth parameters and its implications in the preparationw of materials susceptible to biodeterioration. Fungi were isolated from soils of different ecological sites at a range of substrate aw levels controlled by sodium chloride (NaCl). Three groups of fungi were isolated : firstly, those isolated only at high a (aw about 0.997).secondly, those isolated at high and decreasing aw (aw 0.997 to 0.85) and finally, those isolated at only decreased aw (aw O.95 to 0.80). From these isolations, test fungi were selected to study the effects of pH, temperature, exo-enzyme production and biocide efficacy at decreased aw levels, with glycerol and NaCl as a controlling solutes. The linear extension rates of the fungi increased at all test pH values near optimum a of growth. Test fungi of the Aspergillus glaucus group were found to be most resistant to low aw. Growth and survival of vegetative and fruiting bodies at elevated temperatures were enhanced with the addition of a controlling solutes. A. flavus, A. fumigatus displayed high heat resistance and A. amstelodami, A. versicolor and Penicillium citrinum displayed low heat resistance at high aw levels and vice versa at low aw levels. Amylase, lipase and protease activities were studied at lowered aw , using modifications of the test tube method of Raute11a and Cowling. Amylase and protease production in most xerophilic fungi ceased around 0.80 aw , but lipase production in some xerophilic fungi, including A. glatlcus fungi, was up to and including 0.70 aw with g1ycero1.