910 research outputs found

    A Cretaceous carbonate delta drift in the Montagna della Maiella, Italy

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    The Upper Cretaceous (Campanian\u2013Maastrichtian) bioclastic wedge of the Orfento Formation in the Montagna della Maiella, Italy, is compared to newly discovered contourite drifts in the Maldives. Like the drift deposits in the Maldives, the Orfento Formation fills a channel and builds a Miocene delta-shaped and mounded sedimentary body in the basin that is similar in size to the approximately 350 km 2 large coarse-grained bioclastic Miocene delta drifts in the Maldives. The composition of the bioclastic wedge of the Orfento Formation is also exclusively bioclastic debris sourced from the shallow-water areas and reworked clasts of the Orfento Formation itself. In the near mud-free succession, age-diagnostic fossils are sparse. The depositional textures vary from wackestone to float-rudstone and breccia/conglomerates, but rocks with grainstone and rudstone textures are the most common facies. In the channel, lensoid convex-upward breccias, cross-cutting channelized beds and thick grainstone lobes with abundant scours indicate alternating erosion and deposition from a high-energy current. In the basin, the mounded sedimentary body contains lobes with a divergent progradational geometry. The lobes are built by decametre thick composite megabeds consisting of sigmoidal clinoforms that typically have a channelized topset, a grainy foreset and a fine-grained bottomset with abundant irregular angular clasts. Up to 30 m thick channels filled with intraformational breccias and coarse grainstones pinch out downslope between the megabeds. In the distal portion of the wedge, stacked grainstone beds with foresets and reworked intraclasts document continuous sediment reworking and migration. The bioclastic wedge of the Orfento Formation has been variously interpreted as a succession of sea-level controlled slope deposits, a shoaling shoreface complex, or a carbonate tidal delta. Current-controlled delta drifts in the Maldives, however, offer a new interpretation because of their similarity in architecture and composition. These similarities include: (i) a feeder channel opening into the basin; (ii) an excavation moat at the exit of the channel; (iii) an overall mounded geometry with an apex that is in shallower water depth than the source channel; (iv) progradation of stacked lobes; (v) channels that pinch out in a basinward direction; and (vi) smaller channelized intervals that are arranged in a radial pattern. As a result, the Upper Cretaceous (Campanian\u2013Maastrichtian) bioclastic wedge of the Orfento Formation in the Montagna della Maiella, Italy, is here interpreted as a carbonate delta drift

    Precision Measurement of the 29Si, 33S, and 36Cl Binding Energies

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    The binding energies of 29Si, 33S, and 36Cl have been measured with a relative uncertainty <0.59×106< 0.59 \times 10^{-6} using a flat-crystal spectrometer. The unique features of these measurements are 1) nearly perfect crystals whose lattice spacing is known in meters, 2) a highly precise angle scale that is derived from first principles, and 3) a gamma-ray measurement facility that is coupled to a high flux reactor with near-core source capability. The binding energy is obtained by measuring all gamma-rays in a cascade scheme connecting the capture and ground states. The measurements require the extension of precision flat-crystal diffraction techniques to the 5 to 6 MeV energy region, a significant precision measurement challenge. The binding energies determined from these gamma-ray measurements are consistent with recent highly accurate atomic mass measurements within a relative uncertainty of 4.3×1074.3 \times 10^{-7}. The gamma-ray measurement uncertainties are the dominant contributors to the uncertainty of this consistency test. The measured gamma-ray energies are in agreement with earlier precision gamma-ray measurements.Comment: 13 pages, 4 figure

    Monitoraggio ambientale e biologico dell’esposizione ad idrocarburi mono-aromatici ed a metil tert-butil etere in un gruppo di lavoratori addetti all’erogazione di carburanti

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    Lo studio è stato condotto per valutare gli indicatori biologici di esposizione a vapori di benzina in lavoratori addetti all’erogazione di carburante tramite un approccio combinato di monitoraggio ambientale e biologico. L’esposizione personale a benzene, toluene, etilbenzene e xilene (BTEX) e l’escrezione urinaria di BTEX, metil tert-butil etere (MTBE-U), degli acidi trans,transmuconico (t,t-MA) ed S-fenilmercapturico (S-PMA) e della cotinina sono stati valutati con tecniche cromatografiche accoppiate alla spettrometria di massa. I livelli di MTBE-U erano influenzati dalla sola esposizione professionale a vapori di benzina, mentre quelli di B-U ed S-PMA dipendevano da abitudine tabagica ed esposizione professionale

    Tissue expression of lactate transporters (MCT1 and MCT4) and prognosis of malignant pleural mesothelioma (brief report)

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    Background: Malignant pleural mesothelioma (MPM) is an aggressive neoplasm of the pleura, mainly related to asbestos exposure. As in other solid tumors, malignant cells exhibit high glucose uptake and glycolytic rates with increased lactic acid efflux into the interstitial space. Lactate transport into and out of cells, crucial to maintaining intracellular pH homeostasis and glycolysis, is carried out by monocarboxylate transporters (MCTs) and the chaperone basigin (CD147). We set out to examine the clinical significance of basigin, MCT1 and MCT4 in the context of MPM and to evaluate their expression in relation to the evolution of the disease. Methods: We used immunohistochemistry to measure the expression of basigin, MCT1 and MCT4 in a cohort of 135 individuals with MPM compared to a series of 15 non-MPM pleura specimens. Moreover, by Kaplan-Meier and Cox analyses we evaluated whether an expression over the average of these markers could be associated with the patients' overall survival (OS). Results: We detected positive staining of basigin, MCT1, and MCT4 in most MPM specimens. In particular, MCT4 was always positive in malignant tissues but undetectable in the 4 normal pleural specimens incorporated within the tissue microarray. This was confirmed in the additional series of 15 normal pleural samples. Moreover, MCT4 expression was significantly associated with reduced OS. Conclusion: In this study, the tissue expression of basigin did not prove to be exploitable as a diagnostic or prognostic marker for MPM patients. The expression of MCT1 was not informative either, being tightly correlated with that of basigin. However, the expression of MCT4 showed promise as a diagnostic/therapeutic and prognostic biomarker

    Occupational asphyxiation by unknown compound(s): Environmental and toxicological approach

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    During a routine truck-tank washing operation, five healthy workers were found motionless inside an empty tanker. Four of them died inside the tanker while the fifth died the following day in hospital. Since the true nature of the fatal compound(s) were not known, a rigorous environmental and toxicological approach supported by autopsy findings was essential to clarify the cause of death.Environmental results indicated that H2S fumes arising from the liquid sulfur previously shipped were responsible for the serial deaths, also confirmed by a simulation performed on two similar truck-tanks.These environmental findings were supported by toxicological analyses through the measurement of thiosulfate, one of the main H2S metabolites. Abnormal thiosulfate concentrations from 1.1 to 186.2mg/kg were revealed in all post-mortem biological samples (blood, lung, liver, kidney, brain and fat). Finally, the cluster analysis performed on thiosulfate body distribution contributed to establishing the time of death according to the accident scene reconstruction.This report presents valuable findings in correctly identifying the cause of death in gas asphyxiation cases by unknown compound(s). © 2009 Elsevier Ireland Ltd

    Diagnóstico molecular de huanglongbing dos citros, via qPCR, em mudas de valência sobre Swingle.

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    O HLB é, sem dúvidas, a grande ameaça da citricultura no país, por ser uma doença severa e destrutiva, com prejuízos no desenvolvimento da planta e na produção de frutos. Os agentes causais da doença são espécies da bactéria Candidatus Liberibacter spp., que se alojam em vasos do floema. Três espécies de Liberibacter estão associadas ao HLB dos citros: Ca. Liberibacter africanus, Ca. L. asiaticus e Ca. L. americanus, sendo as duas últimas de ocorrência no Brasil. A doença pode se propagar através de seu vetor, o psilídeo Diaphorina citri, e/ou por enxertia de tecidos infectados (Bové, 2006). O HLB não provoca a morte das plantas, mas, com o passar dos anos, elas se tornam debilitadas e improdutivas. Pomares inteiros podem ficar inviáveis economicamente dentro de sete a dez anos após o aparecimento da primeira planta sintomática se as medidas de controle não forem tomadas (Gottwald et al., 2007).O período de incubação do HLB depende de vários fatores, variando geralmente de seis a doze meses (Bové, 2006). Diante disso, a inspeção visual do pomar não representa o controle da doença, visto que plantas assintomáticas, porém infectadas, podem permanecer como fontes de inóculo para plantas ainda sadias. Como discutido por Bové (2006) e Gottwald et al. (2007), o conhecimento da proporção de plantas sintomáticas e assintomáticas é importante e deve ser utilizado na decisão da eliminação de pomares inteiros altamente infestados. Assim, a detecção de Ca. Liberibacter sp. precocemente é de extrema importância, pois minimiza, dentro do possível, o impacto financeiro aos citricultores com a erradicação das plantas.Hoje o método mais confiável para o diagnóstico do HLB é o PCR quantitativo em tempo real (qPCR), que amplifica e detecta o DNA bacteriano presente no tecido. O método visual é também utilizado, porém o diagnóstico é impreciso e pode levar a falsos negativos (plantas infectadas e ainda assintomáticas) ou falsos positivos, uma vez que os sintomas da doença podem ser facilmente confundidos com deficiência nutricional.pdf 186

    YbeY is required for ribosome small subunit assembly and tRNA processing in human mitochondria.

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    Mitochondria contain their own translation apparatus which enables them to produce the polypeptides encoded in their genome. The mitochondrially-encoded RNA components of the mitochondrial ribosome require various post-transcriptional processing steps. Additional protein factors are required to facilitate the biogenesis of the functional mitoribosome. We have characterized a mitochondrially-localized protein, YbeY, which interacts with the assembling mitoribosome through the small subunit. Loss of YbeY leads to a severe reduction in mitochondrial translation and a loss of cell viability, associated with less accurate mitochondrial tRNASer(AGY) processing from the primary transcript and a defect in the maturation of the mitoribosomal small subunit. Our results suggest that YbeY performs a dual, likely independent, function in mitochondria being involved in precursor RNA processing and mitoribosome biogenesis. Issue Section: Nucleic Acid Enzymes

    Characterization of clastic sedimentary enviroments by clustering algorithm and several statistical approaches — case study, Sava Depression in Northern Croatia

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    Abstract This study demonstrates a method to identify and characterize some facies of turbiditic depositional environments. The study area is a hydrocarbon field in the Sava Depression (Northern Croatia). Its Upper Miocene reservoirs have been proved to represent a lacustrine turbidite system. In the workflow, first an unsupervised neural network was applied as clustering method for two sandstone reservoirs. The elements of the input vectors were the basic petrophysical parameters. In the second step autocorrelation surfaces were used to reveal the hidden anisotropy of the grid. This anisotropy is supposed to identify the main continuity directions in the geometrical analyses of sandstone bodies. Finally, in the description of clusters several parametric and nonparametric statistics were used to characterize the identified facies. Obtained results correspond to the previously published interpretation of those reservoir facies
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