988 resultados para 172-1061


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Ten ODP sites drilled in a depth transect (2164-4775 m water depth) during Leg 172 recovered high-deposition rate (>20 cm/kyr) sedimentary sections from sediment drifts in the western North Atlantic. For each site an age model covering the past 0.8-0.9 Ma has been developed. The time scales have a resolution of 10-20 kyr and are derived by tuning variations of estimated carbonate content to the orbital parameters precession and obliquity. Based on the similarity in the signature of proxy records and the spectral character of the time series, the sites are divided into two groups: precession cycles are better developed in carbonate records from a group of shallow sites (2164-2975 m water depth, Sites 1055-1058) while the deeper sites (2995-4775 m water depth, Sites 1060-1063) are characterized by higher spectral density in the obliquity band. The resulting time scales show excellent coherence with other dated carbonate and isotope records from low latitudes. Besides the typical Milankovitch cyclicity significant variance of the resulting carbonate time series is concentrated at millennial-scale changes with periods of about 12, 6, 4, 2.5, and 1.5 kyr. Comparisons of carbonate records from the Blake Bahama Outer Ridge and the Bermuda Rise reveal a remarkable similarity in the time and frequency domain indicating a basin-wide uniform sedimentation pattern during the last 0.9 Ma.

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ix Ocean Drilling Program (ODP) sites, in the Northwest Atlantic have been used to investigate kinematic and chemical changes in the "Western Boundary Undercurrent" (WBUC) during the development of full glacial conditions across the Marine Isotope Stage 5a/4 boundary (~70,000 years ago). Sortable silt mean grain size(sort s) measurements are employed to examine changes in near bottom flow speeds, together with carbon isotopes measured in benthic foraminifera and % planktic foraminiferal fragmentation as proxies for changes in water-mass chemistry. A depth transect of cores, spanning 1.8-4.6 km depth, allows changes in both the strength and depth of the WBUC to be constrained across millennial scale events. Sort s measurements reveal that the flow speed structure of the WBUC during warm intervals ("interstadials") was comparable to modern (Holocene) conditions. However, significant differences are observed during cold intervals, with higher relative flow speeds inferred for the shallow component of the WBUC (~2 km depth) during all cold "stadial" intervals (including Heinrich Stadial 6), and a substantial weakening of the deep component (~3-4 km) during full glacial conditions. Our results therefore reveal that the onset of full glacial conditions was associated with a regime shift to a shallower mode of circulation (involving Glacial North Atlantic Intermediate Water) that was quantitatively distinct from preceding cold stadial events. Furthermore, our chemical proxy data show that the physical response of the WBUC during the last glacial inception was probably coupled to basin-wide changes in the water-mass composition of the deep Northwest Atlantic.

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Understanding changes in ocean circulation during the last deglaciation is crucial to unraveling the dynamics of glacial-interglacial and millennial climate shifts. We used neodymium isotope measurements on postdepositional iron-manganese oxide coatings precipitated on planktonic foraminifera to reconstruct changes in the bottom water source of the deep western North Atlantic at the Bermuda Rise. Comparison of our deep water source record with overturning strength proxies shows that both the deep water mass source and the overturning rate shifted rapidly and synchronously during the last deglacial transition. In contrast, any freshwater perturbation caused by Heinrich event 1 could have only affected shallow overturning. These findings show how changes in upper-ocean overturning associated with millennial-scale events differ from those associated with whole-ocean deglacial climate events.

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Sediments from Sites 1057 and 1061 of Ocean Drilling Program Leg 172 on the Blake Outer Ridge exhibit nearly isotropic magnetic susceptibility. Resolving the degree of anisotropy of magnetic susceptibility proved difficult in many samples because of the generally weak magnetic susceptibility of the sediments relative to the noise level of the susceptibility meters used. Lineation varies from 1.0 to 1.013 and foliation varies from 1.0 to 1.08 in the samples that pass rejection criteria. In general the foliation is better resolved than the lineation, particularly at Site 1061, where the foliation exhibits long-term trends that mimic the mean susceptibility. The changes in the foliation at this site are likely the result of changes in the magnetic mineralogy of the sediment. The poorly developed or absent magnetic fabric in the sediments overall can be attributed to high carbonate concentrations and to a circulation regime that was diffuse or with currents too weak to effectively align magnetic particles.

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Background: This open-label, randomised phase III study was designed to further investigate the clinical activity and safety of SRL172 (killed Mycobacterium vaccae suspension) with chemotherapy in the treatment of non-small-cell lung cancer (NSCLC). Patients and methods: Patients were randomised to receive platinum-based chemotherapy, consisting of up to six cycles of MVP (mitomycin, vinblastine and cisplatin or carboplatin) with (210 patients) or without (209 patients) monthly SRL172. Results: There was no statistical difference between the two groups in overall survival (primary efficacy end point) over the course of the study (median overall survival of 223 days versus 225 days; P = 0.65). However, a higher proportion of patients were alive at the end of the 15-week treatment phase in the chemotherapy plus SRL172 group (90%), than in the chemotherapy alone group (83%) (P = 0.061). At the end of the treatment phase, the response rate was 37% in the combined group and 33% in the chemotherapy alone group. Patients in the chemotherapy alone group had greater deterioration in their Global Health Status score (-14.3) than patients in the chemotherapy plus SRL172 group (-6.6) (P = 0.02). Conclusion: In this non-placebo controlled trial, SRL172 when added to standard cancer chemotherapy significantly improved patient quality of life without affecting overall survival times. © 2004 European Society for Medical Oncology.

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Contenido: Naturaleza del conocimiento humano : el significado de la abstracción en Santo Tomás (II) / Octavio Nicolás Derisi – Nacimiento, vida y transfiguración del filósofo griego / Cesáreo López Salgado – La transformación ockhamista de la teoría de la suposición / Ignacio Miralbell – La noción de lugar en Guillermo de Ockham / Olga L. Larre ; J. E. Bolzán – Notas y comentarios -- Bibliografía

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O chamado Grupo dos Trinta e Dois Constituintes revisou o projeto de Constituição, do Relator Bernardo Cabral (PMDB-AM), e reduziu o texto para duzentos e cinquenta artigos. O Deputado Israel Pinheiro (PMDB-MG) declara que o texto constitucional ficou mais organizado, mais articulado, após a revisão. Não houve preocupação em tocar nos pontos polêmicos do projeto, mas apenas de enxugar o texto original, deixando para a lei ordinária o que não é constitucional. O Senador Virgílio Távora (PDS-CE) considera que foi uma tentativa válida de auxílio. O Deputado Ulysses Guimarães (PMDB-SP), a quem foi entregue a nova versão, considerou que é uma contribuição importante, assim como outras tantas que chegarão. Balanço da primeira semana de entrega das emendas populares a Assembleia Nacional Constituinte (ANC). Representantes de empregados em empresas de telecomunicações de todo o país entregam emenda na qual pedem a manutenção do monopólio estatal nos serviços de telecomunicação e a criação do Conselho Nacional de Comunicação, que garanta a cada brasileiro o direito à informação livre e sem censura. Representantes das cooperativas entregam emenda na qual pedem a auto-gestão dos seus negócios, o ensino do cooperativismo e a isenção de impostos. Roberto Rodrigues, representante das cooperados, diz que quando a cooperativa vende algum insumo para o cooperado, cobrando dele um diferencial referente ao custo operacional da cooperativa, não pode haver incidência de imposto. O Deputado Ivo Vanderlinde (PMDB-SC) considera positivo o fortalecimento do cooperativismo. O Deputado Bernardo Cabral (PMDB-AM) mostra entusiasmo ao receber as emendas populares. Fernando Gabeira, jornalista e escritor, convoca o povo a participar.

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Parlamentares de todos os partidos procuram o consenso em torno do projeto de Constituição. O Deputado Israel Pinheiro Filho (PMDB-MG) esclarece que a preocupação é encontrar um texto constitucional que seja mais reduzido, mais enxuto, mas que represente a vontade da sociedade brasileira. Pacifistas denunciam a fabricação indiscriminada de armas nucleares, quarenta e dois anos após a Bomba de Hiroshima. O atual projeto de Constituição admite o uso da energia nuclear somente para fins pacíficos. O Deputado Fabio Feldmann (PMDB-SP) esclarece que muitas pessoas defendem a bomba atômica como um instrumento da paz, o que é um claro absurdo. Ele apoia a emenda popular proposta pela Sociedade Brasileira para o Progresso da Ciência (SBPC) que proíbe a bomba atômica brasileira. Sessão Extraordinária da Assembleia Nacional Constituinte (ANC) debateu a Reforma Agrária. O Deputado Roberto Jefferson (PTB-RJ) criticou a esquerda e considera que a distinção entre terras improdutivas e terras inexploradas deve ser feita pela justiça, pois a violência inviabilizará a Reforma Agrária. O Deputado Aldo Arantes (PC do B-GO) afirma que o atual projeto é a expressão da vontade dos latifundiários e propõe limite ao tamanho das propriedades rurais.