Search results for "phenomena"
showing 10 items of 8379 documents
Evidence of a non-conservative mass transfer in the ultra-compact X-ray source XB 1916-053
2020
The dipping source XB 1916-053 is a compact binary system with an orbital period of 50 min harboring a neutron star. Using ten new {\it Chandra} observations and one {\it Swift/XRT} observation, we are able to extend the baseline of the orbital ephemeris; this allows us to exclude some models that explain the dip arrival times. The Chandra observations provide a good plasma diagnostic of the ionized absorber and allow us to determine whether it is placed at the outer rim of the accretion disk or closer to the compact object. From the available observations we are able to obtain three new dip arrival times extending the baseline of the orbital ephemeris from 37 to 40 years. From the analysis…
Salivary proteome and sensitivity to bitterness
2010
Among the various factors that dictate food choices, the sensorial acceptability and the in-mouth perception of food are essential. For example, bitterness is partly responsible for the rejection of some vegetables by some consumers. In this study, the aim is to evaluate if the salivary environment of an individual plays a role in his sensitivity to bitter taste
On the slabbing of stones throughdiamond wire cutting
2010
Diamond wires are usually used in the cutting operations aimed to obtain slabs of stones. This tool consists of a steel cable on which are mounted annular metal–diamond pearls. The use of this technology expanded all over the world because of its advantages on other slabbing techniques as both technical and economical aspects are considered. It should be observed that with this technology wear phenomena must be properly monitored in order to obtain the best process conditions. Inthis article, thediamondwire cutting operation is investigated, highlighting the process mechanics and the wear phenomena occurring in the used tools. Furthermore, a modified version of the tool itself is proposed w…
Global analysis of the pMSSM in light of the Fermi GeV excess: prospects for the LHC Run-II and astroparticle experiments
2016
We present a new global fit of the 19-dimensional phenomenological Minimal Supersymmetric Standard Model (pMSSM-19) that comply with all the latest experimental results from dark matter indirect, direct and accelerator dark matter searches. We show that the model provides a satisfactory explanation of the excess of gamma-rays from the Galactic centre observed by the Fermi~Large Area Telescope, assuming that it is produced by the annihilation of neutralinos in the Milky Way halo. We identify two regions that pass all the constraints: the first corresponds to neutralinos with a mass ~80-100 GeV annihilating into WW with a branching ratio of 95% ; the second to heavier neutralinos, with mass ~…
Synchrotron x-ray transmission measurements and modeling of filters investigated for Athena
2020
International audience; Advanced Telescope for High-Energy Astrophysics is a large-class astrophysics space mission selected by the European Space Agency to study the theme "Hot and Energetic Universe." The mission essentially consists of a large effective area x-ray telescope and two detectors: the X-ray Integral Field Unit (X-IFU) and the Wide Field Imager (WFI). Both instruments require filters to shield from out-of-band radiation while providing high transparency to x-rays. The mission is presently in phase B; thus, to consolidate the preliminary design, investigated filter materials need to be properly characterized by experimental test campaigns. We report results from high-resolution…
High yield neutron generator based on a high-current gasdynamic electron cyclotron resonance ion source
2015
In present paper, an approach for high yield compact D-D neutron generator based on a high current gasdynamic electron cyclotron resonance ion source is suggested. Results on dense pulsed deuteron beam production with current up to 500 mA and current density up to 750 mA/cm2 are demonstrated. Neutron yield from D2O and TiD2 targets was measured in case of its bombardment by pulsed 300 mA Dþ beam with 45 keV energy. Neutron yield density at target surface of 109 s 1 cm2 was detected with a system of two 3 He proportional counters. Estimations based on obtained experimental results show that neutron yield from a high quality TiD2 target bombarded by Dþ beam demonstrated in present work accele…
Delayed and In-beam Spectroscopy on Francium and Astatine Nuclei at the Proton Drip Line
2011
Delayed and in‐beam spectroscopy on francium and astatine nuclei at and beyond the proton drip line has been performed. In neutron deficient astatine nuclei a shift to deformed shapes as a function of decreasing neutron has been obtained. In neutron deficient francium isotope the same shift is evident.
Hydro-mechanical modelling of MX-80 bentonite: one dimensional study
2016
As a first step towards modelling the coupled Thermo-Hydro-Mechanical-Chemical (THMC) behaviour of bentonite, the Barcelona Basic Model (BBM) has been implemented into Numerrin finite element code. This model has been fully coupled with the single phase flow equation for unsaturated soils which models liquid water transport. Suction obtained from solving the flow equation is used as an input for the BBM model and the volumetric deformations from the mechanical analysis are used to update the pore water pressure field. As an alternative, BBM is used alongside the Kröhn’s model which assumes that bentonite re-saturation is mainly driven by water vapour diffusion. The paper simulates one dimen…
Task-focused behaviour and mothers' causal attributions in relation to dyslexia : a follow-up from age 8 to age 20
2018
Children with dyslexia tend to find reading stressful. Coping responses, such as task-focused and avoidant behaviours, can help mitigate the stress. Task-focused behaviour is associated with reading development, with others’ at-tributions of success and failure linked to task-focused behaviour. The present study aims to examine whether differences in task-focused behaviour between those with dyslexia and those without dyslexia exist in childhood (age 8) and persist in adolescence (age 15) and early adulthood (age 20). The study also aimed to understand the relationship between mothers’ causal attributions of their 15-year-old adolescents’ school successes and fail-ures and task-focused beha…
The effect of perceived school climate and teacher efficacy in behavior management on job satisfaction and burnout: A longitudinal study
2016
Abstract This study investigated how perceived school climate affects teachers' job satisfaction and burnout and how self-efficacy and collective efficacy in behavior management mediate the effect of perceived school climate on job satisfaction and burnout. The questions were answered using longitudinal questionnaire data collected from 642 Finnish lower secondary school teachers. A structural equation model revealed that school climate had a positive effect, partly mediated by self-efficacy, on job satisfaction. Collective efficacy in student discipline did not explain either job satisfaction or burnout. Self-efficacy in managing behavior had a positive effect on job satisfaction and a neg…