Morphometry and debris-flow susceptibility map in mountain drainage basins of the Vallo di Diano, southern Italy

In watershed mountain basins, affected in the last decades by strong rainfall events, the role of debris-flow and debris flood processes was investigated. Morphometric parameters have proven to be useful first-approximation indicators in discriminating those processes, especially in large areas of investigation. Computation of morphometric parameters in 19 watershed mountain basins of the western side valley of the Vallo di Diano intermontane basin (southern Italy) was carried out. This procedure was integrated by a semi-automatic elaboration of the potential susceptibility to debris flows, using Flow-R modelling. This software, providing an empirical model of the preliminary susceptibility assessment at a regional scale, was applied in many countries of the world. The implementation of Flow-R modelling requires a GIS application and some thematic base maps extracted using DEMs analysis. A 5-meter-resolution DEM has been used in order to produce the susceptibility maps of the whole study area, and the results are compared and discussed with the real debris flow/flood events that occurred in 1993, 2005, 2010, and 2017 in the studied area. The results have provided a good reliability of Flow-R modelling within small catchment mountain basins

Theoretical study of the heteroepitaxial growth of Pd on Cu(111), Pd on Ni(111), Ni on Pd(111), and Cu on Pd(111) using a semiempirical method

CNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPEMIG - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE MINAS GERAISHeteroepitaxy has been widely studied by many different theoretical and experimental techniques. Each technique focuses on some features of the growth process, and only by combining the information each provides a full characterization can be given. In this work, the growth of Pd on Ni (111), Pd on Cu (111),Cu on Pd (111), and Ni on Pd (111) is studied with a purely energetic approach which consists of determining a unit cell with a size that depends on the relation between the lateral misfit of the deposited film and the substrate. The energetic is evaluated using a semiempirical coupled with a genetic algorithm global search method to determine with accuracy the relaxation magnitudes of the system. With this approach, features such as interlayer spacings, variation in the film's lattice parameter with coverage, and diffusion influence in the growth process are studied qualitative and quantitatively. The results obtained are directly compared with experimental findings from literature and also presented in this work. The theory-experiment comparison shows that the methodology used is successful in describing qualitatively most features of all four systems. However, for the Pd on Cu (111) case, poor agreement is found, and the analysis of the influence of diffusion and temperature suggests that a somewhat complex alloy formation in the interface is expected for this particular system.Heteroepitaxy has been widely studied by many different theoretical and experimental techniques. Each technique focuses on some features of the growth process, and only by combining the information each provides a full characterization can be given. In this work, the growth of Pd on Ni (111), Pd on Cu (111),Cu on Pd (111), and Ni on Pd (111) is studied with a purely energetic approach which consists of determining a unit cell with a size that depends on the relation between the lateral misfit of the deposited film and the substrate. The energetic is evaluated using a semiempirical coupled with a genetic algorithm global search method to determine with accuracy the relaxation magnitudes of the system. With this approach, features such as interlayer spacings, variation in the film's lattice parameter with coverage, and diffusion influence in the growth process are studied qualitative and quantitatively. The results obtained are directly compared with experimental findings from literature and also presented in this work. The theory-experiment comparison shows that the methodology used is successful in describing qualitatively most features of all four systems. However, for the Pd on Cu (111) case, poor agreement is found, and the analysis of the influence of diffusion and temperature suggests that a somewhat complex alloy formation in the interface is expected for this particular system.818114CNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPEMIG - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE MINAS GERAISCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPEMIG - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE MINAS GERAISSem informaçãoSem informaçã

Unacylated-Ghrelin Impairs Hippocampal Neurogenesis and Memory in Mice and Is Altered in Parkinson’s Dementia in Humans

Blood-borne factors regulate adult hippocampal neurogenesis and cognition in mammals. We report that elevating circulating unacylated-ghrelin (UAG), using both pharmacological and genetic methods, reduced hippocampal neurogenesis and plasticity in mice. Spatial memory impairments observed in ghrelin-O-acyl transferase-null (GOAT/) mice that lack acyl-ghrelin (AG) but have high levels of UAG were rescued by acyl-ghrelin. Acyl-ghrelin-mediated neurogenesis in vitro was dependent on non-cell-autonomous BDNF signaling that was inhibited by UAG. These findings suggest that post-translational acylation of ghrelin is important to neurogenesis and memory in mice. To determine relevance in humans, we analyzed circulating AG:UAG in Parkinson disease (PD) patients diagnosed with dementia (PDD), cognitively intact PD patients, and controls. Notably, plasma AG:UAG was only reduced in PDD. Hippocampal ghrelin-receptor expression remained unchanged; however, GOAT+ cell number was reduced in PDD. We identify UAG as a regulator of hippocampal-dependent plasticity and spatial memory and AG:UAG as a putative circulating diagnostic biomarker of dementia

Epitaxial growth of ultrathin palladium films on Re{0001}

Ultrathin bimetallic layers create unusual magnetic and surface chemical effects through the modification of electronic structure brought on by low dimensionality, polymorphism, reduced screening, and epitaxial strain. Previous studies have related valence and core-level shifts to surface reactivity through the d-band model of Hammer and Nørskov, and in heteroepitaxial films this band position is determined by competing effects of coordination, strain, and hybridization of substrate and overlayer states. In this study we employ the epitaxially matched Pd on Re{0001} system to grow films with no lateral strain. We use a recent advancement in low-energy electron diffraction to expand the data range sufficiently for a reliable determination of the growth sequence and out-of-plane surface relaxation as a function of film thickness. The results are supported by scanning tunneling microscopy and X-ray photoemission spectroscopy, which show that the growth is layer-by-layer with significant core-level shifts due to changes in film structure, morphology, and bonding

Genetics of VEGF Serum Variation in Human Isolated Populations of Cilento: Importance of VEGF Polymorphisms

Vascular Endothelial Growth Factor (VEGF) is the main player in angiogenesis. Because of its crucial role in this process, the study of the genetic factors controlling VEGF variability may be of particular interest for many angiogenesis-associated diseases. Although some polymorphisms in the VEGF gene have been associated with a susceptibility to several disorders, no genome-wide search on VEGF serum levels has been reported so far. We carried out a genome-wide linkage analysis in three isolated populations and we detected a strong linkage between VEGF serum levels and the 6p21.1 VEGF region in all samples. A new locus on chromosome 3p26.3 significantly linked to VEGF serum levels was also detected in a combined population sample. A sequencing of the gene followed by an association study identified three common single nucleotide polymorphisms (SNPs) influencing VEGF serum levels in one population (Campora), two already reported in the literature (rs3025039, rs25648) and one new signal (rs3025020). A fourth SNP (rs41282644) was found to affect VEGF serum levels in another population (Cardile). All the identified SNPs contribute to the related population linkages (35% of the linkage explained in Campora and 15% in Cardile). Interestingly, none of the SNPs influencing VEGF serum levels in one population was found to be associated in the two other populations. These results allow us to exclude the hypothesis that the common variants located in the exons, intron-exon junctions, promoter and regulative regions of the VEGF gene may have a causal effect on the VEGF variation. The data support the alternative hypothesis of a multiple rare variant model, possibly consisting in distinct variants in different populations, influencing VEGF serum levels

Impact of flavonoid-rich black tea and beetroot juice on postprandial peripheral vascular resistance and glucose homeostasis in obese, insulin-resistant men: a randomized controlled trial.

BACKGROUND: Insulin-stimulated muscle blood flow facilitates plasma glucose disposal after a meal, a mechanism that is impaired in obese, insulin-resistant volunteers. Nitrate- or flavonoid-rich products, through their proposed effects on nitric oxide, may improve postprandial blood flow and, subsequently, glucose disposal. To investigate whether a single dose of nitrate-rich beetroot juice or flavonoid-rich black tea lowers postprandial muscle vascular resistance in obese volunteers and alters postprandial glucose or insulin concentrations. METHOD: In a randomised, controlled, cross-over study, 16 obese, insulin-resistant males consumed 75 g glucose, which was combined with 100 ml black tea, beetroot juice or control (water). Peripheral vascular resistance (VR), calculated as mean arterial pressure divided by blood flow, was assessed in the arm and leg conduit arteries, resistance arteries and muscle microcirculation across 3 h (every 30-min) after the oral glucose load. RESULTS: During control, we found no postprandial response in VR in conduit, resistance and microvessels (all P > 0.05). Black tea decreased VR compared to control in conduit, resistance and microvessels (all P < 0.05). Beetroot juice decreased postprandial VR in resistance vessels, but not in conduit artery and microvessels. Although postprandial glucose response was similar after all interventions, postprandial insulin response was attenuated by ~29 % after tea (P < 0.0005), but not beetroot juice. CONCLUSIONS: A single dose of black tea decreased peripheral VR across upper and lower limbs after a glucose load which was accompanied by a lower insulin response. Future studies in insulin-resistant subjects are warranted to confirm the observed effects and to explore whether long-term regular tea consumption affects glucose homeostasis. TRIAL REGISTRATION: The study was registered at clinicaltrials.gov on 30(th) November 2012 (NCT01746329)

Calorie for calorie, dietary fat restriction results in more body fat loss than carbohydrate restriction in people with obesity

© 2015 Elsevier Inc. Dietary carbohydrate restriction has been purported to cause endocrine adaptations that promote body fat loss more than dietary fat restriction. We selectively restricted dietary carbohydrate versus fat for 6 days following a 5-day baseline diet in 19 adults with obesity confined to a metabolic ward where they exercised daily. Subjects received both isocaloric diets in random order during each of two inpatient stays. Body fat loss was calculated as the difference between daily fat intake and net fat oxidation measured while residing in a metabolic chamber. Whereas carbohydrate restriction led to sustained increases in fat oxidation and loss of 53 ± 6 g/day of body fat, fat oxidation was unchanged by fat restriction, leading to 89 ± 6 g/day of fat loss, and was significantly greater than carbohydrate restriction (p = 0.002). Mathematical model simulations agreed with these data, but predicted that the body acts to minimize body fat differences with prolonged isocaloric diets varying in carbohydrate and fat