LEAP-UCD-2017 Centrifuge Test Simulation at UNINA

Within the framework of the LEAP-UCD-2017 exercise, Type B simulations of centrifuge tests were conducted assuming a hypoplastic constitutive model for sand. Differently from the most common elastoplastic approach, the hypoplasticity does not decompose the strain rate into elastic and plastic parts and does not use explicitly the notions of the yield surface and plastic potential surface. The process followed to calibrate the constitutive model is presented in detail. The initial state of stresses in the analyzed mesh, the key parameters used in the dynamic simulation phase, and a comparison of the simulation with some experimental results are reported. All the simulations were performed using the model parameters calibrated by using the laboratory test data. Finally, a sensitivity analysis of computed displacement to soil density and ground motion intensity show the influence of such factors on the seismic soil response of liquefiable soils

Population of Merging Compact Binaries Inferred Using Gravitational Waves through GWTC-3

We report on the population properties of compact binary mergers inferred from gravitational-wave observations of these systems during the first three LIGO-Virgo observing runs. The Gravitational-Wave Transient Catalog 3 (GWTC-3) contains signals consistent with three classes of binary mergers: binary black hole, binary neutron star, and neutron star-black hole mergers. We infer the binary neutron star merger rate to be between 10 and 1700 Gpc-3 yr-1 and the neutron star-black hole merger rate to be between 7.8 and 140 Gpc-3 yr-1, assuming a constant rate density in the comoving frame and taking the union of 90% credible intervals for methods used in this work. We infer the binary black hole merger rate, allowing for evolution with redshift, to be between 17.9 and 44 Gpc-3 yr-1 at a fiducial redshift (z=0.2). The rate of binary black hole mergers is observed to increase with redshift at a rate proportional to (1+z)κ with κ=2.9-1.8+1.7 for z≲1. Using both binary neutron star and neutron star-black hole binaries, we obtain a broad, relatively flat neutron star mass distribution extending from 1.2-0.2+0.1 to 2.0-0.3+0.3M⊙. We confidently determine that the merger rate as a function of mass sharply declines after the expected maximum neutron star mass, but cannot yet confirm or rule out the existence of a lower mass gap between neutron stars and black holes. We also find the binary black hole mass distribution has localized over- and underdensities relative to a power-law distribution, with peaks emerging at chirp masses of 8.3-0.5+0.3 and 27.9-1.8+1.9M⊙. While we continue to find that the mass distribution of a binary's more massive component strongly decreases as a function of primary mass, we observe no evidence of a strongly suppressed merger rate above approximately 60M⊙, which would indicate the presence of a upper mass gap. Observed black hole spins are small, with half of spin magnitudes below χi≈0.25. While the majority of spins are preferentially aligned with the orbital angular momentum, we infer evidence of antialigned spins among the binary population. We observe an increase in spin magnitude for systems with more unequal-mass ratio. We also observe evidence of misalignment of spins relative to the orbital angular momentum

Body fat distribution and its association with hypertension in a sample of mexican children

Background: The association between elevated blood pressure and childhood overweight and obesity has been documented in several studies. However, the linkage of blood pressure with body fat distribution in children is not well established.We investigated the relationship between both central and subcutaneous adiposity with BP in the 95th percentile or higher in Mexican children. Methods and Results: Our study, using a sample of children from the State of Guerrero, Mexico was comprised of 252 children, 124 girls and 128 boys, with an age range of 6 to 13 years. Resting blood pressure was measured in duplicate with an aneroid sphygmomanometer. Hypertension was classified as systolic or diastolic BP in the 95th percentile or higher. Additional measures included weight, height, body mass index, body circumferences, and skinfold thickness. The prevalence of obesity (26.5%) was higher than overweight (15.8%), but the prevalence of hypertension was moderate (4.7%). Both systolic and diastolic blood pressures correlated strongly with age, weight, height, and all measurements of central and subcutaneous adiposity. Interestingly, after being adjusted by age, sex, and body mass index, the BP in the 95th percentile or higher was associated with suprailiac skinfold, third tertile (OR = 11.83, P = 0.023); triceps skinfold, third tertile (OR = 6.02; P = 0.034); and biceps skinfold, third tertile (OR = 4.71; P = 0.038). Conclusions: Our data indicate that the prevalence of hypertension in children is moderate. In addition, the skinfold thickness was a better predictor of hypertension than central adiposity in the sample of children studied. Copyright © 2011 by The American Federation for Medical Research

Preparación de polvos de óxido de itrio activado con lantánido

Se prepararon fósforos de oxido de itrio (Y2O3), impurificados con praseodimio utilizando como reactivos Y(NO3)3 y PrCl3 disueltos en metanol, a la temperatura de 700°C. Por difracción de rayos X se determino la estructura del Y2O3 resultando ser de tipo cúbico. Estos fósforos emiten luz naranja-roja que corresponde al rango de 620-670nm de la región visible. Debido a las transiciones del nivel excitado 1D2 al nivel basal 3H4. Estos espectros de emisión fotolumiscentes se muestran a diferentes concentraciones

Síntesis e impurificación en medio alcalino de Y2O3 con propiedades luminiscentes

Se obtuvo el oxido de itrio (Y2O3), utilizando como reactivos de partida YCl3 e NH4OH disueltos en agua destilada, mediante la técnica de precipitación a la temperatura de 600°C. Por difracción de rayos X se determino la estructura del Y2O3 resultando ser de tipo cúbico. Este óxido se impurifico con dos iones de la serie de los lantánidos el Tb y Eu. Se muestran los espectros de emisión fotolumiscentes de estos iones activantes presentes en la red huésped del Y2O

Elevated concentration of asymmetric dimethylarginine (ADMA) in individuals with metabolic syndrome

he metabolic syndrome (MS) is a cluster of pathophysiological alterations that includes the presence of hypertension, insulin resistance, dyslipidemia, and abdominal obesity. MS is associated with increased risk of developing diabetes and cardiovascular diseases. Endothelial dysfunction with impaired nitric oxide (NO) bioavailability has been implicated in insulin resistance and hypertension. NO is synthesized by nitric oxide synthase (NOS) using L-arginine as substrate. Asymmetric dimethyl arginine (ADMA) is a major and potent endogenous NOS inhibitor, associated with cardiovascular and renal diseases. We tested the hypothesis that plasmatic ADMA levels are increased in patients with MS. We studied 85 adult individuals from Talca, Chile, separated in two groups, 48 individuals with MS (according to modified ATP III criteria), and 37 individuals without MS as controls. ADMA levels were significantly increased in the MS group (mean +/- standard deviation 0.71 +/- 0.38 vs. 0.48 +/- 0.28 mu mol/L, p = 0.0009). Furthermore, the levels of ADMA were modestly but significantly correlated with waist circumference (p = 0.01) but not with the other components of MS (blood pressure, glycemia, triglycerides and high density lipoprotein cholesterol HDL-c). These results suggest a possible link between increased ADMA levels and the MS. (C) 2011 Elsevier Inc. All rights reserved

Microsatellite analysis reveals connectivity among geographically distant transmission zones of Plasmodium vivax in the Peruvian Amazon: A critical barrier to regional malaria elimination.

Despite efforts made over decades by the Peruvian government to eliminate malaria, Plasmodium vivax remains a challenge for public health decision-makers in the country. The uneven distribution of its incidence, plus its complex pattern of dispersion, has made ineffective control measures based on global information that lack the necessary detail to understand transmission fully. In this sense, population genetic tools can complement current surveillance. This study describes the genetic diversity and population structure from September 2012 to March 2015 in three geographically distant settlements, Cahuide (CAH), Lupuna (LUP) and Santa Emilia (STE), located in the Peruvian Amazon. A total 777 P. vivax mono-infections, out of 3264, were genotyped. Among study areas, LUP showed 19.7% of polyclonal infections, and its genetic diversity (Hexp) was 0.544. Temporal analysis showed a significant increment of polyclonal infections and Hexp, and the introduction and persistence of a new parasite population since March 2013. In STE, 40.1% of infections were polyclonal, with Hexp = 0.596. The presence of four genetic clusters without signals of clonal expansion and infections with lower parasite densities compared against the other two areas were also found. At least four parasite populations were present in CAH in 2012, where, after June 2014, malaria cases decreased from 213 to 61, concomitant with a decrease in polyclonal infections (from 0.286 to 0.18), and expectedly variable Hexp. Strong signals of gene flow were present in the study areas and wide geographic distribution of highly diverse parasite populations were found. This study suggests that movement of malaria parasites by human reservoirs connects geographically distant malaria transmission areas in the Peruvian Amazon. The maintenance of high levels of parasite genetic diversity through human mobility is a critical barrier to malaria elimination in this region

Electrical, optical and structural characteristics of Al2O3 thin films prepared by pulsed ultrasonic sprayed pyrolysis

The optical, structural, and electrical characteristics of aluminum oxide thin films deposited by pulsed ultrasonic sprayed pyrolysis are reported. The films are deposited on crystalline silicon at temperatures from 400 to 550°C using a chemical solution of aluminum acetylacetonate, as source of aluminum, and N, N-dimethylformamide, as solvent. A H2O–NH4OH mist is supplied simultaneously during deposition to improve the films’ properties. The results showed that the properties of the as deposited films depended strongly on the number of pulses used and on the substrate temperature. The thickness of the films is under 300 Å and the best films’ properties showed an index of refraction close to 1.6 and a root mean square surface roughness of about 7.5 Å in average. Infrared spectroscopy shows that SiO2 is observed at the interface with silicon of the Al2O3 films and seemed to play, as expected, a dramatic role in the electrical characteristics of the interface. Films with a dielectric constant higher than 8 and an interface trap density at midgap in the 1010 eV−1 cm−2 range are obtained. Films deposited with three pulses and at 550 °C are able to stand an electric field up to 4 MV/cm