41 research outputs found

    Pliocene Te Aute limestones, New Zealand: Expanding concepts for cool-water shelf carbonates

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    Acceptance of a spectrum of warm- through cold-water shallow-marine carbonate facies has become of fundamental importance for correctly interpreting the origin and significance of all ancient platform limestones. Among other attributes, properties that have become a hallmark for characterising many Cenozoic non-tropical occurrences include: (1) the presence of common bryozoan and epifaunal bivalve skeletons; (2) a calcite-dominated mineralogy; (3) relatively thin deposits exhibiting low rates of sediment accumulation; (4) an overall destructive early diagenetic regime; and (5) that major porosity destruction and lithification occur mainly in response to chemical compaction of calcitic skeletons during moderate to deep burial. The Pliocene Te Aute limestones are non-tropical skeletal carbonates formed at paleolatitudes near 40-42°S under the influence of commonly strong tidal flows along the margins of an actively deforming and differentially uplifting forearc basin seaway, immediately inboard of the convergent Pacific-Australian plate boundary off eastern North Island, New Zealand. This dynamic depositional and tectonic setting strongly influenced both the style and subsequent diagenetic evolution of the limestones. Some of the Te Aute limestones exhibit the above kinds of "normal" non-tropical characteristics, but others do not. For example, many are barnacle and/or bivalve dominated, and several include attributes that at least superficially resemble properties of certain tropical carbonates. In this regard, a number of the limestones are infaunal bivalve rich and dominated by an aragonite over a calcite primary mineralogy, with consequently relatively high diagenetic potential. Individual limestone units are also often rather thick (e.g., up to 50-300 m), with accumulation rates from 0.2 to 0.5 m/ka, and locally as high as 1 m/ka. Moreover, there can be a remarkable array of diagenetic features in the limestones, involving grain alteration and/or cementation to widely varying extents within any, or some combination of, the marine phreatic, burial, and meteoric diagenetic environments, including locally widespread development of meteoric cement sourced from aragonite dissolution. The message is that non-tropical shelf carbonates include a more diverse array of geological settings, of skeletal and mineralogical facies, and of diagenetic features than current sedimentary models mainly advocate. While several attributes positively distinguish tropical from non-tropical limestones, continued detailed documentation of the wide spectrum of shallow-marine carbonate deposits formed outside tropical regions remains an important challenge in carbonate sedimentology

    Surgical and percutaneous revascularization outcomes based on SYNTAX I, II, and residual scores: A long-term follow-up study

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    BACKGROUND: The objective of this study was to evaluate the association of SYNTAX scores I, II, and residual with cardiovascular outcomes of patients undergoing coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI) and compare both procedures in a long-term follow-up. METHODS: This is a retrospective single-center study from the MASS registry at the Heart Institute of the University of São Paulo, Brazil in which 969 patients with stable coronary artery disease undergoing CABG (559) or PCI (410) were included. We assessed the SYNTAX scores I, II and residual in both interventions. Clinical endpoints were the first occurrence of a composite of overall death, myocardial infarction, stroke, or repeat revascularization (MACCE) and the total occurrence of each component of MACCE. RESULTS: In the CABG sample, SSI had a median of 23 (IQR 17-29.5), median SSII of 25.4 (IQR 19.2-32.8), and median rSS of 2 (IQR 0-6.5); in PCI SSI had a median of 14 (IQR 10-19.1), median SSII of 28.7 (IQR 23-34.2), and median rSS of 4.7 (IQR 0-9). Total of 174 events were documented and CABG patients had a lower rate of MACCE (15.6% vs. 21.2%; adjusted HR 1.98; 95% CI 1.13-3.47; P = 0.016) and repeat revascularization (3.8% vs. 11.5%; adjusted HR 4.35; CI 95% 1.74-10.85; P = 0.002) compared with PCI. No SYNTAX score tertile found a difference in death rate between procedures. In a multivariate analysis, the rSS was an independent predictor for MACCE (HR 1.04; 95% CI 1.01-1.06; P = 0.001). Regarding death, the only independent predictors were ejection fraction and renal function. CONCLUSION: Surgical revascularization resulted in a more complete revascularization and lower rates of major cardiac or cerebrovascular events in a long-term follow-up. Also, grading the incompleteness of revascularization through the residual SYNTAX score identified a higher event rate, suggesting that complete revascularization is associated with a better prognosis

    Banco de dados de experimentos para fins de simulação em desenvolvimento de culturas agrícolas.

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    O artigo descreve a importĂąncia de um banco de dados para experimentos agrĂ­colas na Embrapa e no SNPA (Sistema Nacional de Pesquisa AgropecuĂĄria) para fins de simulação em crescimento de culturas baseado na estrutura do DSSAT que foi apresentado em palestra nesse Workshop. Aborda-se o assunto na forma de um estudo de caso, onde empregou-se a tĂ©cnica orientada a objetos (OMT de James Rum baugh) na anĂĄlise do problema pra facilitar a captura de requisitos junto aos pesquisadores (futuros usuĂĄrios do sistema). Exemplifica-se o uso da tĂ©cnica OMT, mostrando-se a sua coerĂȘncia entre modelos, adequação ao estudo de controle de experimentos e as dificuldades entradas no trabalho

    Glycoprotein Hormone Receptor Knockdown Leads to Reduced Reproductive Success in Male Aedes aegypti

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    Glycoprotein hormone receptors mediate a diverse range of physiological functions in vertebrate and invertebrate organisms. The heterodimeric glycoprotein hormone GPA2/GPB5 and its receptor LGR1, constitute a recently discovered invertebrate neuroendocrine signaling system that remains to be functionally characterized. We previously reported that LGR1 is expressed in the testes of adult Aedes aegypti mosquitoes, where its immunoreactivity is particularly regionalized. Here, we show that LGR1 immunoreactivity is associated with the centriole adjunct of spermatids and is observed transiently during spermatogenesis in mosquitoes, where it may act to mediate the regulation of flagellar development. RNA interference to downregulate LGR1 expression was accomplished by feeding mosquito larvae with bacteria that produced LGR1-specific dsRNA, which led to defects in spermatozoa, characterized with shortened flagella. LGR1 knockdown mosquitoes also retained ∌60% less spermatozoa in reproductive organs and demonstrated reduced fertility compared to controls. To date, the endocrine regulation of spermatogenesis in mosquitoes remains an understudied research area. The distribution of LGR1 and detrimental effects of its knockdown on spermatogenesis in A. aegypti indicates that this heterodimeric glycoprotein hormone signaling system contributes significantly to the regulation of male reproductive biology in this important disease-vector
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