Search results for "PTO"

Sport participation and loneliness in adolescents: the mediating role of perceived social competence

2013

Published version of an article in the journal: Current Psychology. Also available from the publisher at: http://dx.doi.org/10.1007/s12144-013-9174-5 Young people perceive loneliness as a distressing emotional experience associated with sadness and boredom. Also, feelings of loneliness may be associated with psychosocial and emotional problems during adolescence. The aim of this study was to investigate whether perceived social competence mediated the cross-sectional relationship between sport participation and loneliness in young people when controlling for age, sex, shyness, and non-organized physical activity. This cross-sectional study consisted of 2,055 pupils (995 boys and 1,060 girls…

Identification of new ligands for sigma receptors. Design and synthesis of a beta-aminoketonic drug discovery library

2009

Charge Transport Mechanisms in Heavy-Ion Driven Leakage Current in Silicon Carbide Schottky Power Diodes

2016

Under heavy-ion exposure at sufficiently high reverse bias voltages silicon carbide (SiC) Schottky diodes are observed to exhibit gradual increases in leakage current with increasing ion fluence. Heavy-ion exposure alters the overall reverse current-voltage characteristics of these diodes, leaving the forward characteristics practically unchanged. This paper discusses the charge transport mechanisms in the heavy-ion damaged SiC Schottky diodes. A macro model, describing the reverse current-voltage characteristics in the degraded SiC Schottky diodes is proposed. peerReviewed

Effect of the Si doping on the properties of AZO/SiC/Si heterojunctions grown by low temperature pulsed laser deposition

2020

Abstract The structural and photoelectrical properties of Al-doped ZnO (AZO)/SiC/p-Si and AZO/SiC/n-Si heterojunctions, fabricated at low temperature by pulsed laser deposition, were investigated by means of a number of techniques. Raman analysis indicates that SiC layers have the cubic 3C-SiC phase, whilst X-ray diffraction measurements show that AZO films exhibit a hexagonal wurtzite structure, highly textured along the c-axis, with average crystallites size of 35.1 nm and lattice parameter c of 0.518 nm. The homogeneous and dense surface morphology observed by scanning electron microscopy was confirmed by atomic force microscopy images. Moreover, UV–Vis-NIR spectra indicated a high trans…

Depresijas simptomu novērtējums klīniskā un neklīniskā izlasē

2021

Šī pētījuma mērķis ir noskaidrot, kādi ir depresijas simptomu profili mērījumos starp klīnisko un neklīnisko (vispārējo) izlasi. Pētījuma galvenais jautājums bija, kādi būs indivīdiem novērojami depresijas simptomu profili jeb kāda būs depresijas simptomu heterogenitāte? Pētījumā piedalījās 292 respondenti. Pētījuma dalībnieki bija vecumā no 14 līdz 53 gadiem (M = 34,27; SD = 11,12; sievietes 75,3%; vīrieši 24,7%). Pētījuma ietvaros tika izveidotas divas izlases – neklīniskā jeb vispārējā izlase un klīniskā izlase. Vispārējo izlasi veidoja 262 respondenti, savukārt klīnisko izlasi veidoja 30 respondenti. Pētījuma veikšanai tika izmantotas divas aptaujas – Depresijas simptomu aptauja, kā arī…

Time resolved emission at 1.3 μm of a single InAs quantum dot by using a tunable fibre Bragg grating

2013

Photoluminescence and time resolved photoluminescence from single metamorphic InAs/GaAs quantum dots (QDs) emitting at 1.3 mu m have been measured by means of a novel fibre-based characterization set-up. We demonstrate that the use of a wavelength tunable fibre Bragg grating filter increases the light collection efficiency by more than one order of magnitude as compared to a conventional grating monochromator. We identified single charged exciton and neutral biexciton transitions in the framework of a random population model. The QD recombination dynamics under pulsed excitation can be understood under the weak quantum confinement potential limit and the interaction between carriers at the …

Development of high resolution and efficiency detectors based on Silicon Photomultipliers (SIPMS) and continuous crystals for medical physics applica…

2017

El trabajo presentado en esta tesis introduce y evalúa dos aspectos novedosos en los detectores de rayos gamma para imagen médica: el uso de fotomultiplicadores de silicio (SiPMs, en inglés) acoplados a cristales centelleadores continuos. Tradicionalmente, los tubos fotomultiplicadores (PMTs, en inglés) acoplados a cristales centelleadores han jugado un papel dominante en la detección de rayos gamma. En los últimos años ha aparecido un nuevo tipo de fotodetector de estado sólido, el SiPM, como opción para sustituir a los PMTs en ciertas aplicaciones. Los SiPMs tienen una ganancia y una eficiencia cuántica altas, un voltaje de operación bajo y unas propiedades temporales excelentes. Además, …

Dolor y recaída en el alcoholismo: alteraciones en la función moduladora del sistema opioide endógeno sobre el sistema dopaminérgico mesocorticolímbi…

2020

Durant els últims anys, múltiples estudis clínics i epidemiològics han revelat que la presència de dolor crònic està estretament relacionada amb el trastorn per consum d'alcohol (AUD). De fet, el dolor crònic sembla augmentar el risc de patir AUD i predir el consum excessiu d'alcohol i la recaiguda en aquells pacients amb antecedents d'abús d'alcohol. A més, s'ha informat que el dolor té un impacte negatiu en el processament motivacional i de recompensa, ja que altera la funció de sistema mesocorticolímbic (MCLS). Els receptors opioides mu (MOR) són components clau del MCLS i són essencials per al processament de recompenses tant d'estímuls naturals com de drogues d'abús, inclòs l'alcohol. …

Vegetation series as a marker of interactions between rural settlements and landscape: new insights from the archaeological record in Western Sicily

2020

[EN] Plant communities are complex and dynamic elements of the landscape, intertwined with both natural factors and human activities. Vegetation series reflect the environmental characteristics of the landscape, but also the anthropic impact, one of the exogenous forces that most profoundly affects the landscape formation process. This paper aims to investigate the interactions between long-term human settlement catchment areas and vegetation series. The case study area of the Sicani Mountains (Central-Western Sicily) proved to be an ideal place to perform GIS-based spatial analysis in order to compare a data set of rural archaeological sites and land units created through the mapping of ve…

H1-antihistamines suppress wheal-and-flare reaction and skin blood perfusion measured by Laser Dopppler flowmetry: randomized, double-blind, placebo-…

2010

H1-antihistamines suppress wheal-and-flare reaction and skin blood perfusion measured by Laser Dopppler flowmetry: randomized, double-blind, placebo-controlled, crossover design study The aim of our study was to compare the influence of pre-treatment with H1-antihistamines (levocetirizine, desloratadine, clemastine, quifenadine, and sequifenadine) and a placebo on the histamine-induced weal and flare reaction, increase of skin blood perfusion and sedation. Thirty healthy volunteers were enrolled in the study. The study design was a prospective, randomised, double-blind, placebo-controlled, crossover, balanced clinical trial. Volunteers in randomised and double-blind order were treated with …