Search results for "Clima"
showing 10 items of 6069 documents
Do organizational and job-related factors relate to organizational commitment? : a mixed method study of the associations
2011
Pulsating B and Be stars in the Small Magellanic Cloud
2008
Context: Stellar pulsations in main-sequence B-type stars are driven by the kappa-mechanism due to the Fe-group opacity bump. The current models do not predict the presence of instability strips in the B spectral domain at very low metallicities. As the metallicity of the SMC is lower than Z=0.005, it constitutes a very suitable object to test these predictions. Aims: The main objective is to investigate the existence of B-type pulsators at low metallicities, searching for short-term periodic variability in absorption-line B and Be stars in the SMC. The analysis has been performed in a sample of 313 B and Be stars with fundamental astrophysical parameters accurately determined from high-res…
DFT Prediction of Enhanced Reducibility of Monoclinic Zirconia upon Rhodium Deposition.
2018
Oxides are an important class of materials and are widely used, for example, as supports in heterogeneous catalysis. In a number of industrial catalytic processes, oxide supports actively participate in chemical transformations by releasing lattice oxygen anions. While this is intuitively understood for reducible oxides, the reducibility of irreducible oxides may be modified via nanoengineering or upon inclusion of foreign species. Our calculations predict that the ability of irreducible monoclinic zirconia to release oxygen improves substantially upon deposition of rhodium. Through a comprehensive screening of Rh/ZrO2 with different size of the rhodium species, we find that a Rh adatom and…
Measurement of the average shape of longitudinal profiles of cosmic-ray air showers at the Pierre Auger Observatory
2019
The profile of the longitudinal development of showers produced by ultra-high energy cosmic rays carries information related to the interaction properties of the primary particles with atmospheric nuclei. In this work, we present the first measurement of the average shower profile in traversed atmospheric depth at the Pierre Auger Observatory. The shapes of profiles are well reproduced by the Gaisser-Hillas parametrization within the range studied, for E>10 17.8 eV .A detailed analysis of the systematic uncertainties is performed using ten years of data and a full detector simulation. The average shape is quantified using two variables related to the width and asymmetry of the profile, and …
Ambiente e clima della Sicilia durante gli ultimi 20 mila anni
2010
Environment and Climate in Sicily over the last 20, 000 years. (IT ISSN 0394-3356, 2010). A series of recent studies shed light on the central Mediterranean, and Sicily, climate and environment, starting from the last glacial maximum (about 20 ka cal BP). In the present paper, we examine most of these works, in order to unravel environmental changes of the past, mainly in terms of temperature, atmospheric pattern, precipitation, vegetation and faunal associations. The climate of the last glacial maximum was characterised by very low temperature and by repeated northerlies penetration, even during summer. Low precipitation values led to a steppe- or semisteppe-like vegetation pattern, domina…
German and British parliaments and conceptions of the global climate threat during the United Nation Earth Summit of 1992
2019
Ever since the beginning of international climate conservation politics there has been variation across nations in political traditions in debating the climate issue. Political decision-makers have interpreted the scientific findings on global warming with different emphases, thereby giving rise to variation in views on preferred national or international solutions. These tensions first became evident before and during the Earth Summit of the United Nations in 1992 in Rio de Janeiro, when the United Nations Climate Change Convention was prepared and eventually signed. This article discusses the historical background of international climate conservation politics and illustrates the tensions…
Razones para emigrar de los jóvenes españoles: consumo de los medios de comunicación y variables psicosociales
2017
El estudio de las migraciones y la movilidad humana es un tema complejo, motivado por un amplio número de razones, que requiere un análisis multidisciplinar para comprender el proceso migratorio y sus consecuencias tanto en la vida del migrante como en la de sus familias. El principal objetivo del presente estudio es 1) conocer la importancia que los jóvenes españoles no emigrantes y emigrantes dan a un amplio número de razones para emigrar junto con 2) la relación que mantienen dichos motivos con el consumo de los medios de comunicación y la imagen que tienen de los programas de televisión sobre los emigrantes, así como 3) analizar las relaciones entre las razones para emigrar y un conjunt…
Coping Strategies against peer victimization: differences according to gender, grade, victimization status and perceived classroom social climate
2021
The Sustainable Development Goals (SDGs) include “Good Health and Well-being” (SDG3) and “Quality Education” (SDG4). Nevertheless, many students cannot achieve these goals if they suffer peer victimization at their schools, and intervention programs to reduce it are necessary. These programs should consider the possible differences in the coping strategies preferred by students according to some personal (e.g., gender, grade, victimization status) and contextual (e.g., perceived classroom social climate) factors to be more effective. Therefore, the objective of this study was to analyze the possible differences in the coping strategies preferred by students (ask a friend for help, ask a tea…
The importance of psychological variables in the perceived exertion of young football players
2017
Las escalas para medir la percepción del esfuerzo están entre los métodos que han sido utilizados para el control y la evaluación de la carga interna del entrenamiento en deportes de equipo como el fútbol. Debido a su naturaleza psicofisiológica, su registro proporciona información proveniente tanto de indicadores fisiológicos como psicológicos del deportista. Dentro del marco de la Teoría de la Autodeterminación (SDT, Self Determination Theory; Deci & Ryan, 1985; Ryan & Deci, 2017) y de la Teoría de las Metas de Logro (AGT, Achievement Goal Theory; Ames, 1992; Nicholls, 1989), en esta tesis doctoral se estudian tanto las variables contextuales desadaptativas (dimensiones del clima motivaci…
New Evidence of the Enhanced Elimination of a Persistent Drug Used as a Lipid Absorption Inhibitor by Advanced Oxidation with UV-A and Nanosized Cata…
2019
This work demonstrates new evidence of the efficient destruction and mineralization of an emergent organic pollutant using UV-A and titanium nanosized catalysts. The target compound considered in this work is the primary metabolite of a lipid regulator drug, clofibrate, identified in many studies as refractory during conventional wastewater treatment. The photocatalytic performance study was carried out in batch mode at laboratory scale, in aqueous suspension. Kinetic data showed that titanium dioxide P25 Aeroxide® exhibits the highest photocatalytic efficiency compared to the other investigated catalysts. Pollutant degradation and mineralization efficiencies strongly increased when decreas…