Control of oceanic circulation on sediment distribution in the southwestern Atlantic margin (23 to 55º S)

In this study, we interpret the role played by ocean circulation in sediment distribution on the southwestern Atlantic margin using radiogenic Nd and Pb isotopes. The latitudinal trends for Pb and Nd isotopes reflect the different current systems acting on the margin. The utilization of the sediment fingerprinting method allowed us to associate the isotopic signatures with the main oceanographic features in the area. We recognized differences between Nd and Pb sources to the Argentinean shelf (carried by the flow of Subantarctic Shelf Water) and slopes (transported by deeper flows). Sediments from Antarctica extend up to the Uruguayan margin, carried by the Upper and Lower Circumpolar Deep Water. Our data confirm that, for shelf and intermediate areas (the upper 1200 m), the transfer of sediments from the Argentinean margin to the north of 35∘ S is limited by the Subtropical Shelf Front and the basin-wide recirculated Antarctic Intermediate Water. On the southern Brazilian inner and middle shelf, it is possible to recognize the northward influence of the Río de la Plata sediments carried by the Plata Plume Water. Another flow responsible for sediment transport and deposition on the outer shelf and slope is the southward flow of the Brazil Current. Finally, we propose that the Brazil–Malvinas Confluence and the Santos Bifurcation act as boundaries of geochemical provinces in the area. A conceptual model of sediment sources and transport is provided for the southwestern Atlantic margin

Osman Lins and the Suplemento Literário of O Estado de São Paulo (1956-1961): comparisons with his fictional work

Osman Lins e o Suplemento Literário dO Estado de São Paulo (1956-1961): cotejos com sua obra ficcional apresenta um levantamento de temáticas observadas na produção não-ficcional do escritor pernambucano correspondente a um suposto período de formação do ficcionista como apresentado por Osman Lins em Guerra sem testemunhas , estabelecendo cotejos entre essas temáticas e sua obra ficcional madura. Considerando o referido levantamento temático, estabelecem-se análises das reflexões estéticas, éticas e morais do crítico Osman Lins, reflexões essas que se apresentam de forma muito lúcida e em diversos momentos extremamente combatente. As análises estabelecidas nesta dissertação procuram verificar laços existentes entre a produção crítica e a obra ficcional de Lins, aceitando-se como premissa que a obra crítica de um escritor ficcional possa apresentar reflexões do escritor a partir de suas observações críticas e julgamentos de valor. Esta dissertação tem como objetivos gerais promover a divulgação de uma produção não-ficcional de Osman Lins inédita em livro, bem como oferecer ferramentas de pesquisa a outros estudiosos da obra do escritor pernambucano. Não se pretende, de modo algum, esgotar as possibilidades temáticas do corpus desta pesquisa; tampouco se busca apresentar análises exaustivas dos temas estudados. Este é apenas o início de um trabalho que se acredita ser parte de um percurso longo e muito produtivo.Osman Lins and the Suplemento Literário of O Estado de São Paulo (1956-1961): comparisons with his fictional work presents a survey of themes which have been observed in the nonfiction production of the Pernambucan writer and which correspond with a supposed formative period in the writers work as it is presented by Osman Lins in Guerra sem testemunhas , establishing comparisons between those themes and his mature fiction production. Considering the mentioned survey of themes, some analysis of the critic Osman Lins esthetic, ethical and moral reflections were established. Those reflections are presented in a very lucid and, many times, extremely combatant way. The established analysis in this dissertation long for verify possible bonds between the writers nonfiction production and his fiction work, accepting the premise that the critical production of a fiction writer might present reflections of the writer in his critical observations and value judgments. This dissertation aims to promote the spreading of some Osman Lins unpublished nonfiction production, as well as to offer some instruments to other researchers of the Pernambucan writers work. This study does not aim, nowhere near, to use up the possible themes of this researchs corpus; neither longs for present exhaustive analysis of the studied themes. It is just the beginning of a work which is believed to be part of a long and very productive trajectory

Sedimentation in the adjacencies of a southwestern Atlantic giant carbonate ridge

Although carbonate mounds have been investigated for 100 years, few studies focus on the giant variety. The Alpha Crucis Carbonate Ridge (ACCR), a ~17 x 12-km ring-shaped ridge formed by hundreds of mounded structures, located between the 300 and 800-m isobaths and reaching a maximum height of 340 meters above the adjacent seafloor, is the first giant carbonate mounded feature described for the SW Atlantic margin. This study provides the first multiproxy approach to investigate sediments covering the ACCR and its adjacencies. Most of the area is located under the Intermediate Western Boundary Current (IWBC) flow, which carries the nutrient-rich Antarctic Intermediate Water (AAIW). Radiocarbon aging shows pronounced differences for the shallow layers (MIS3 for the top of the mounds and late Holocene for the adjacencies). Grain size data indicate the prevalence of sandy fractions on top of the mounds and muddy sediments in the adjacent areas. Fe/Ca and Ti/Ca proxies allowed for identifying mainly biogenic sedimentation in the area. However, the input of allochthonous terrigenous sediment is necessary for mound buildup, and values of Fe and Ti collected on the top of the mounds are significant. End-Members distributions and metal concentrations also allowed for recognition of distinct sources of sediment. εNd and Ln(Fe/K) indicated two primary terrigenous sources, the Precambrian rocks of the Brazilian shield (Cabo Frio end-member) and the multiple lithologies drained by the Rio de la Plata basin. Redox condition proxies indicated that the area is submitted to oxic conditions, probably reflecting the action of the IWBC. This work provides the first insight into an integrated grain-size and geochemical characterization of the Alpha Crucis Carbonate Ridge (southwestern Atlantic margin)

Effects of once-weekly exenatide on cardiovascular outcomes in type 2 diabetes

BACKGROUND: The cardiovascular effects of adding once-weekly treatment with exenatide to usual care in patients with type 2 diabetes are unknown. METHODS: We randomly assigned patients with type 2 diabetes, with or without previous cardiovascular disease, to receive subcutaneous injections of extended-release exenatide at a dose of 2 mg or matching placebo once weekly. The primary composite outcome was the first occurrence of death from cardiovascular causes, nonfatal myocardial infarction, or nonfatal stroke. The coprimary hypotheses were that exenatide, administered once weekly, would be noninferior to placebo with respect to safety and superior to placebo with respect to efficacy. RESULTS: In all, 14,752 patients (of whom 10,782 [73.1%] had previous cardiovascular disease) were followed for a median of 3.2 years (interquartile range, 2.2 to 4.4). A primary composite outcome event occurred in 839 of 7356 patients (11.4%; 3.7 events per 100 person-years) in the exenatide group and in 905 of 7396 patients (12.2%; 4.0 events per 100 person-years) in the placebo group (hazard ratio, 0.91; 95% confidence interval [CI], 0.83 to 1.00), with the intention-to-treat analysis indicating that exenatide, administered once weekly, was noninferior to placebo with respect to safety (P<0.001 for noninferiority) but was not superior to placebo with respect to efficacy (P=0.06 for superiority). The rates of death from cardiovascular causes, fatal or nonfatal myocardial infarction, fatal or nonfatal stroke, hospitalization for heart failure, and hospitalization for acute coronary syndrome, and the incidence of acute pancreatitis, pancreatic cancer, medullary thyroid carcinoma, and serious adverse events did not differ significantly between the two groups. CONCLUSIONS: Among patients with type 2 diabetes with or without previous cardiovascular disease, the incidence of major adverse cardiovascular events did not differ significantly between patients who received exenatide and those who received placebo