96 research outputs found

    Regional Seismic Characterization of Shallow Subsoil of Northern Apulia (Southern Italy)

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    A first-order seismic characterization of Northern Apulia (Southern Italy) has been provided by considering geological information and outcomes of a low-cost geophysical survey. In particular, 403 single-station ambient vibration measurements (HVSR techniques) distributed within the main settlements of the area have been considered to extract representative patterns deduced by Principal Component Analysis. The joint interpretation of these pieces of information allows the identification of three main domains (Gargano Promontory, Bradanic Through and Southern Apennines Fold and Thrust Belt), each characterized by specific seismic resonance phenomena. In particular, the Bradanic Through is homogeneously characterized by low frequency (< 1 Hz) resonance effects associated with relatively deep (> 100 m) seismic impedance, which is contrasting corresponding to the buried Apulian carbonate platform and/or sandy horizons located within the Plio-Pleistocene deposits. In the remaining ones, relatively high frequency (> 1 Hz) resonance phenomena are ubiquitous due to the presence of shallower impedance contrasts (< 100 m), which do not always correspond to the top of the geological bedrock. These general indications may be useful for a preliminary regional characterization of seismic response in the study area, which can be helpful for an effective planning of more detailed studies targeted to engineering purposes

    A global characterization of the translational and transcriptional programs induced by methionine restriction through ribosome profiling and RNA-seq

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    Background: Among twenty amino acids, methionine has a special role as it is coded by the translation initiation codon and methionyl-tRNAi (Met-tRNAi) is required for the assembly of the translation initiation complex. Thus methionine may play a special role in global gene regulation. Methionine has also been known to play important roles in cell growth, development, cancer, and aging. In this work, we characterize the translational and transcriptional programs induced by methionine restriction (MetR) and investigate the potential mechanisms through which methionine regulates gene expression, using the budding yeast S. cerevisiae as the model organism. Results: Using ribosomal profiling and RNA-seq, we observed a broad spectrum of gene expression changes in response to MetR and identified hundreds of genes whose transcript level and/or translational efficiency changed significantly. These genes show clear functional themes, suggesting that cell slows down its growth and cell cycle progression and increases its stress resistance and maintenance in response to MetR. Interestingly, under MetR cell also decreases glycolysis and increases respiration, and increased respiration was linked to lifespan extension caused by caloric restriction. Analysis of genes whose translational efficiency changed significantly under MetR revealed different modes of translational regulation: 1) Ribosome loading patterns in the 5'UTR and coding regions of genes with increased translational efficiency suggested mechanisms both similar and different from that for the translational regulation of Gcn4 under general amino acid starvation condition; 2) Genes with decreased translational efficiency showed strong enrichment of lysine, glutamine, and glutamate codons, supporting the model that methionine can regulate translation by controlling tRNA thiolation. Conclusions: MetR induced a broad spectrum of gene expression changes at both the transcriptional and translational levels, with clear functional themes indicative of the physiological state of the cell under MetR. Different modes of translational regulation were induced by MetR, including the regulation of the ribosome loading at 5'UTR and regulation by tRNA thiolation. Since MetR extends the lifespan of many species, the list of genes we identified in this study can be good candidates for studying the mechanisms of lifespan extension.National Institutes of Health [AG043080]SCI(E)ARTICLE1

    Alterations to Melanocortinergic, GABAergic and Cannabinoid Neurotransmission Associated with Olanzapine-Induced Weight Gain

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    Background/Aim: Second generation antipsychotics (SGAs) are used to treat schizophrenia but can cause serious metabolic side-effects, such as obesity and diabetes. This study examined the effects of low to high doses of olanzapine on appetite/ metabolic regulatory signals in the hypothalamus and brainstem to elucidate the mechanisms underlying olanzapineinduced obesity. Methodology/Results: Levels of pro-opiomelanocortin (POMC), neuropeptide Y (NPY) and glutamic acid decarboxylase (GAD65, enzyme for GABA synthesis) mRNA expression, and cannabinoid CB1 receptor (CB1R) binding density (using [ 3 H]SR-141716A) were examined in the arcuate nucleus (Arc) and dorsal vagal complex (DVC) of female Sprague Dawley rats following 0.25, 0.5, 1.0 or 2.0 mg/kg olanzapine or vehicle (36/day, 14-days). Consistent with its weight gain liability, olanzapine significantly decreased anorexigenic POMC and increased orexigenic NPY mRNA expression in a dose-sensitive manner in the Arc. GAD65 mRNA expression increased and CB1R binding density decreased in the Arc and DVC. Alterations to neurotransmission signals in the brain significantly correlated with body weight and adiposity. The minimum dosage threshold required to induce weight gain in the rat was 0.5 mg/kg olanzapine. Conclusions: Olanzapine-induced weight gain is associated with reduced appetite-inhibiting POMC and increased NPY. This study also supports a role for the CB1R and GABA in the mechanisms underlying weight gain side-effects, possibly b

    High-resolution seismic reflection exploration for evaluating the seismic hazard in a Plio-Quaternary intermontane basin (L'Aquila downtown, central Italy)

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    On April 6, 2009, a Mw 6.1 earthquake struck the Plio-Quaternary intermontane L'Aquila-Scoppito Basin in central Italy, causing severe damage to L'Aquila historical downtown and surroundings, which were affected by notable site effects. Previous work has suggested that different site effects may be related to the complex subsurface geologic architecture, given the variable thickness and lithology of L'Aquila-Scoppito Basin filling deposits, on top of which the city was built. To improve the 3D geological model of L'Aquila downtown for seismic site response evaluation and to estimate the seismic hazard of possible buried active normal faults, a multitask project was carried out consisting mainly of the integration of surface geology, geological subsurface datasets and geophysical surveys. Data were interpreted with the aim of creating and building a detailed stratigraphic and tectonic model for the Plio-Quaternary cover of the continental basin and the buried morphology of the Meso-Cenozoic bedrock. We discuss and interpret the results concerning a 1 km-long high-resolution seismic reflection profile and refraction tomography integrated with stratigraphy from deep and shallow boreholes. The results allowed the reconstruction of the Plio-Quaternary succession below L'Aquila downtown. The Plio-Quaternary basin depocentre is located in a minor NNW-SSE graben, an extensional structure within the main regional graben that borders L'Aquila-Scoppito Basin. Finally, data interpretation allowed us to define the subsoil geological model of the study area, to evidence the recent activity of several faults, and to reconstruct the Plio-Quaternary tectono-stratigraphic evolution of the basin. Together, the data are useful to evaluate the seismic hazard of cities with great cultural heritage of central Italy, such as the case study of L'Aquila downtown
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