963 resultados para 73-522_Site


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The main objective of DSDP Leg 73 was to obtain high-quality records of major paleooceanographic events in the South Atlantic. This was achieved by coring six sites on the African plate. The sediments thus recovered span the Cenozoic and five of the six sites proved ideally suited for magnetostratigraphic analysis. The results presented in this paper and elsewhere in this volume constitute the first opportunity to extend the direct correlation of the magnetostratigraphic and biostratigraphic time-scales into the Paleogene in deep-sea cores. The magnetostratigraphic analyses from DSDP Leg 73 sediments are presented in this paper. The correlation of the magnetostratigraphy to the magnetic polarity time-scale provides tight age-depth control for the five sites analyzed, allowing the accurate calculation of sediment accumulation rates. The data presented here represent a remarkable record of the fine-scale polarity history of the Earth's magnetic field. These data place constraints on the interpretation of smallscale marine magnetic anomalies which are modelled equally effectively by field intensity fluctuations as polarity reversals. At least some of the "tiny wiggles" correspond to very short polarity units in the magnetostratigraphic record. By assuming an axial geocentric dipole, the inclination of the time-averaged magnetic field recorded in the sediments can be used to calculate the paleolatitude at which the sediments were deposited. Combining the age and average inclination information available from the magnetostratigraphy, we present paleolatitudes versus time for the Leg 73 drill sites.

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In the largest global cooling event of the Cenozoic Era, between 33.8 and 33.5 Myr ago, warm, high-CO2 conditions gave way to the variable 'icehouse' climates that prevail today. Despite intense study, the history of cooling versus ice-sheet growth and sea-level fall reconstructed from oxygen isotope values in marine sediments at the transition has not been resolved. Here, we analyse oxygen isotopes and Mg/Ca ratios of benthic foraminifera, and integrate the results with the stratigraphic record of sea-level change across the Eocene-Oligocene transition from a continental-shelf site at Saint Stephens Quarry, Alabama. Comparisons with deep-sea (Sites 522 (South Atlantic) and 1218 (Pacific)) d18O and Mg/Ca records enable us to reconstruct temperature, ice-volume and sea-level changes across the climate transition. Our records show that the transition occurred in at least three distinct steps, with an increasing influence of ice volume on the oxygen isotope record as the transition progressed. By the early Oligocene, ice sheets were ~25% larger than present. This growth was associated with a relative sea-level decrease of approximately 105 m, which equates to a 67 m eustatic fall.

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Constraining the magnitude of high-latitude temperature change across the Eocene-Oligocene transition (EOT) is essential for quantifying the magnitude of Antarctic ice-sheet expansion and understanding regional climate response to this event. To this end, we constructed high-resolution stable oxygen isotope (d18O) and magnesium/calcium (Mg/Ca) records from planktic and benthic foraminifera at four Ocean Drilling Program (ODP) sites in the Southern Ocean. Planktic foraminiferal Mg/Ca records from the Kerguelen Plateau (ODP Sites 738, 744, and 748) show a consistent pattern of temperature change, indicating 2-3 °C cooling in direct conjunction with the first step of a two-step increase in benthic and planktic foraminiferal d18O values across the EOT. In contrast, benthic Mg/Ca records from Maud Rise (ODP Site 689) and the Kerguelen Plateau (ODP Site 748) do not exhibit significant temperature change. The contrasting temperature histories derived from the planktic and benthic Mg/Ca records are not reconcilable, since vertical d18O gradients remained nearly constant at all sites between 35.0 and 32.5 Ma. Based on the coherency of the planktic Mg/Ca records from the Kerguelen Plateau sites and complications with benthic Mg/Ca paleothermometry at low temperatures, the planktic Mg/Ca records are deemed the most reliable measure of Southern Ocean temperature change. We therefore interpret a uniform cooling of 2-3 °C in both deep surface (thermocline) waters and intermediate deep waters of the Southern Ocean across the EOT. Cooling of Southern Ocean surface waters across the EOT was likely propagated to the deep ocean, since deep waters were primarily sourced on the Antarctic margin throughout this time interval. Removal of the temperature component from the observed foraminiferal d18O shift indicates that seawater d18O values increased by 0.6 ± 0.15 per mil across the EOT interval, corresponding to an increase in global ice volume to a level equivalent with 60-130% modern East Antarctic ice sheet volume.

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In 2015 the QLRC is conducting an inquiry into whether to extend legislative mandatory reporting duties for physical abuse and sexual abuse to early childhood education and care practitioners. The current legislation does not require these practitioners to report suspected cases of significant harm from physical or sexual absue to child welfare agencies. Based on the literature, and a multidisciplinary analysis, our overall recommendation is that we endorse the extension to selected early childhood education and care practitioners of Queensland’s current mandatory reporting duty in the Child Protection Act 1999 s 13E.

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Contenido: Ser y entender / Octavio N. Derisi – Filosofía del indeterminismo cuántico / J. E. Bolzán – Arte y metafísica / José M. de Estrada – Notas y comentarios – Bibliografía

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1962-1972 / La Dirección -- La Teología al servicio de la Palabra de Dios / Carmelo Giaquinta -- El “Padre Nuestro” en el Evangelio según san Mateo / Luis H. Rivas -- La liberación. Aspectos bíblicos: evaluación crítica / José Mejía -- Matrimonio y sacerdocio: sacramento, fidelidad, castidad / Eduardo Briancesco -- Palabras y gestos en la Reconciliación sacramental / Luis Alessio -- El matrimonio en los Sínodos del Obispo Trejo / José M. Arancibia -- Propiedad de los medios de producción y pensamiento social de la Iglesia / Carmelo Giaquinta -- Reflexiones acerca de la pastoral popular desde el interior de un santuario / Guillermo Rodríguez Melgarejo -- Algunos principios para una teología de la pastoral popular / Ernesto Mai -- Nota bibliográficas -- Libros recibidos -- Crónica de la Facultad -- Índice del Tomo X

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<正> 眩晕是临床比较常见的一个病症。对于眩晕的病情轻重和治疗效果的评定,主要依靠病人的主诉与医生的判断,目前还没有客观指标。为此,我们住中医辨证治疗眩晕的研究中,用平衡仪对73例眩晕患者进行了平衡试验观察,现将观察结果报告于下。方法和结果一、观察方法眩晕的检测工具为平衡仪(又称重心仪)Gravicorder,由检测平台和放大器二部分组成。检测平台是一块铸铝板(800×800×200毫米~3),它的四角放在四个负荷传感器(BLR-1

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Sediment samples were taken from Lake Langans in Sweden and fossilised diatoms analysed. Sample methods and environmental factors are discussed. Species with a characteristic occurrence are described. The article discusses diatom-thanatocoenoses as indicators of environment.