Search results for " física"
showing 10 items of 920 documents
A theoretical insight into the photophysics of psoralen
2006
Psoralen photophysics has been studied on quantum chemistry grounds using the multiconfigurational second-order perturbation method CASPT2. Absorption and emission spectra of the system have been rationalized by computing the energies and properties of the low-lying singlet and triplet excited states. The S1 ππ* state has been determined to be responsible of the lowest absorption and fluorescence bands and to initially carry the population in the photophysical processes related to the phototherapeutic properties of psoralen derivatives. The low-lying T1 ππ* state is, on the other hand, protagonist of the phosphorescence, and its prevalent role in the reactivity of psoralen is suggested to b…
A INVESTIGAÇÃO NARRATIVA EM EDUCAÇÃO FÍSICA E ESPORTE: QUE É E QUAL A SUA UTILIDADE
2011
Narrative inquiry is a burgeoning form of research in social sciences that has received little attention in physical education and sport sciences. In this article, we seek to balance this situation by offering an understanding of what narrative inquiry can be and can offer to our field. In order to gain some theoretical purchase on a difficult field, we first define narrative. Next, a distillation of guiding assumptions and characteristics are offered. Finally, some reasons as to why narratives may be of benefit for the field of physical education and sport. In conclusion, we consider narrative inquiry as a useful, although problematic, way of theorizing and doing research in the domains of…
Noticias y comentarios de un geógrafo físico sobre sectores litorales españoles (1920-1937)
2003
En esta nota se recopilan, ordenan y comentan las noticias y estudios que el geógrafo J. Carandell (1893-1937) aportó sobre sectores litorales españoles. Estos son especialmente tramos del litoral mediterráneo y en concreto Este de Mallorca, litoral de la provincia de Cádiz, Gibraltar y su entorno, vertiente mediterránea de la Bética y litoral del Bajo Ampurdán. Se alterna y complementan informaciones de aspectos físicos y humanos que pueden ser útiles para el estudio de la comprensión geográfica del litoral español. (A)
Lleicop Rules: Programa de Educación Emocional a través de la Educación Física en la etapa de Educación Primaria: Aplicación en un centro de la Comun…
2017
La Educación Emocional constituye una estrategia viable y eficaz para desarrollar las habilidades emocionales del alumnado ya sea en la escuela o fuera de ella. El objetivo fundamental es que el alumnado pueda conocer tanto sus emociones internas como externas y reconocer las de los demás, incrementando la empatía y habilidades sociales que le permitirán enfrentar el mundo con una visión diferente, desde el trabajo que se realice en la Educación Física. Mediante este programa la Educación Emocional pretende estar presente en los centros educativos de primaria dentro de la programación de Educación Física. Para ello, se ha elaborado “Lleicop Rules”, un programa de Educación Física basado en …
The relationship between the incidence of winners/errors and the time spent in different areas of the court in elite tennis
2013
Martinez-Gallego R, Guzman JF, James N, Ramon-Llin J, Crespo M, Vuckovic G. The relationship between the incidence of winners/errors and the time spent in different areas of the court in elite tennis. J. Hum. Sport Exerc. Vol. 8, No. Proc3, pp. S601-S607, 2013. Winners and errors have been two of the most studied performance indicators in tennis, contributing to the prediction of match outcome and definition of the playing style of the players. Furthermore, the position occupied by the player on the court has also been shown to be a good indicator of both the final result and style of play. The aim of this study was to examine whether there were differences between game winners and losers i…
Magnetic exchange interactions in the heteropoly complexes [M4(H2O)2(PW9O34)2]10− [M=Co(II) and Cu(II)]
1990
The magnetic properties of the heteropolyanions [M4(H2O)2(PW9O34)2]10− [M=Co(II) and Cu(II)] down to 4 K are reported. Their individual heteropoly molecules contain a rhomblike arrangement formed by four coplanar MO6 octahedra sharing edges. The magnetic properties support an intramolecular ferromagnetic exchange in the Co(II) tetramer, and antiferromagnetic exchange in the Cu(II) tetramer. These behaviors are discussed assuming anisotropic exchange in the Co(II) compound, and Heisenberg exchange in the Cu(II) compound. Carlos.Gomez@uv.es
Entanglement-Based dc magnetometry with separated ions
2017
We demonstrate sensing of inhomogeneous dc magnetic fields by employing entangled trapped ions, which are shuttled in a segmented Paul trap. As sensor states, we use Bell states of the type j↑↓i þ eiφj↓↑i encoded in two 40Caþ ions stored at different locations. The linear Zeeman effect leads to the accumulation of a relative phase φ, which serves for measuring the magnetic-field difference between the constituent locations. Common-mode magnetic-field fluctuations are rejected by the entangled sensor state, which gives rise to excellent sensitivity without employing dynamical decoupling and therefore enables accurate dc sensing. Consecutive measurements on sensor states encoded in the S1=2 g…
Global, regional, and national incidence, prevalence, and years lived with disability for 354 diseases and injuries for 195 countries and territories…
2018
The Global Burden of Diseases, Injuries and Risk Factors 2017 includes a comprehensive assessment of incidence, prevalence, and years lived with disability (YLDs) for 354 causes in 195 countries and territories from 1990 to 2017. Previous GBD studies have shown how the decline of mortality rates from 1990 to 2016 has led to an increase in life expectancy, an ageing global population, and an expansion of the non-fatal burden of disease and injury. These studies have also shown how a substantial portion of the world's population experiences non-fatal health loss with considerable heterogeneity among different causes, locations, ages, and sexes. Ongoing objectives of the GBD study include incr…
Moderate-to-Vigorous Physical Activity Levels in Physical Education, School Recess, and After-School Time: Influence of Gender, Age, and Weight Status
2016
Background:Primary and secondary school ages have been considered key moments to address the decrease of moderate-tovigorous physical activity (MVPA). Individual (eg, age, gender, and weight status) and contextual factors (moments of the day) need to be considered for a better explanation of the phenomenon. The quantity and quality of physical activity in Physical Education (PE), school recess (SR), and after school (AS) time need to be taken into account to solve the low levels of MVPA in youth.Methods:A sample of adolescents (N = 231, 14.6 ± 1.2 years old) was studied using accelerometry to determine the objective MVPA level in PE, SR, and AS.Results:Results indicated statistically signif…
Longitudinal association of handgrip strength with all-cause and cardiovascular mortality in older adults using a causal framework.
2022
To date, there is no study addressing the time-varying confounding bias in the association of handgrip strength (HGS) with all-cause or cardiovascular mortality. Therefore, we conducted marginal structural models (MSM) to provide causal estimations on the associations of HGS with all-cause and cardiovascular mortality in a representative sample of adults aged 50 years or older. Data from 29 countries including 121,116 participants (276,994 observations; mean age 63.7 years; 56.3 % women) free from prior heart attack or stroke were retrieved from consecutive waves of the Survey of Health, Ageing and Retirement in Europe (SHARE). During a median of 7.7 years follow-up (interquartile range 3.8…