197 research outputs found
A Lagrangian Transport Model Applied to two Different Brackish Systems: the Baltic Sea and the Guadalquivir River
the nuclear contamination and other passive particles in the
ocean. As a consequence of the Chernobyl accident (April, 26th,
1986), the radioactive plume drift over many countries in Europe,
and after some days, the Baltic Sea became the most
contaminated ecosystem beyond the Soviet Union. Our
Dispersion Model has been validated in this system in order to be
useful in other oceanic scenarios affected by radioactive fallout in
the future. These investigations could be an interesting tool to
predict and minimize the ecological and economical impacts of
future accidents and can also be extended to non-nuclear
contamination problems such as: oil accidents, chemical
contamination, nutrients dynamics and other ecological problems.
A new application devoted to the Guadalquivir River has
been implemented with the methods used and validated for the
Baltic Sea. This transport model is a first step for future
applications to passive particles problems such as nutrients,
chemical contamination, metals, suspended sediments, etc., or
other active parts like salt and fresh water. A deeper knowledge
on the Guadalquivir river estuary is being demanding for many
socioeconomic and ecological applications in the future
Modelización tridimensional del transporte oceánico de 137cs forzado por vientos. Validación en el mar báltico tras el accidente nuclear de Chernobyl
Tesis descargada desde TESEOEsta tesis materializa la segunda mitad de la carrera investigadora del autor, continuación natural de una primera mitad que fue reconocida mediante un sexenio de investigación concedido por la C.N.E.A.I. del Gobierno de España.
Se plantea, desarrolla y valida un modelo numérico (hidrodinámica y transporte: circulación, difusión y sedimentación) para predecir la evolución de manchas radiactivas en el océano, cuya dinámica sea dominada por el viento: se ha aplicado al Mar Báltico, el sistema fuera de la Unión Soviética más afectado por el accidente nuclear de Chernobyl (1986). Se trata del primer modelo radioecológico tridimensional de inducción atmosférica publicado internacionalmente, destacando la influencia de esta línea de trabajo en futuros modelos, como los del Océano Pacífico para la evolución de las manchas provenientes del accidente de Fukushima (2011).
El modelo es de naturaleza lagrangiana y exportable al estudio evolutivo de otras partículas dispersadas en el océano, como la contaminación química, así como a nutrientes y a manchas de petróleo, entre otros problemas. Su metodología ha sido aplicada localmente al estuario del Río Guadalquivir y hay una línea de trabajo sobre este sistema y otros donde pueda retornar la inversión científica de esta trayectoria investigadora que se inició en la Universidad de Uppsala (Suecia) y que se ha desarrollado durante más de una década en la E.T.S. de Ingeniería de la Universidad de Sevilla (España). Los resultados han sido publicados internacionalmente en revistas científicas y presentados por el autor en congresos internacionales organizados por instituciones como el IEEE (EE.UU), la Universidad de Bolonia (Italia), la NASA (EE.UU), el JAMSTEC (Japón) y la Universidad de Cambridge (Reino Unido)
Using oceanography to control and forecast nuclear accidents and other passive particles problems
This article is the last improved version of a previously published model (Toscano-Jimenez and Garcia-Tenorio, 2004) for the transport of the nuclear contamination and other passive particles in the ocean. Two interesting advances have been developed during last two years for the author's PhD thesis to be finished in the next months: (a) a suspended particulate matter (SPM) submodel, including erosion, transport and sedimentation. (b) A new advection-diffusion approach with numerical and computational improvements: finite elements (FE), finite differences (FD) and Monte Carlo (MC) methods have been compared and calibrated. The Baltic Sea has been elected as the validation scenario of the model and the radioisotope 137 Cs is the radiotracer to be analysed. This scenario was the most contaminated ecosystem out of the Soviet Union due to the Chernobyl accident which occurred at the end of April 1986, and the elected radiotracer 137 Cs was the main long-lived radioisotope emitted to the environment. However, an important aim of this model is its potential usefulness in other oceanic scenarios affected by a nuclear disaster in the future. It could be an interesting tool to predict and minimize the ecological and economical impacts of future accidents. This model can also be extended easily to non-nuclear contamination problems such as: oil accidents, nutrients dynamics and other biological problems
To live with an implantable cardioverter defribrillator: A qualitative study on patients'experiences
Objetivo principal: Conocer la experiencia de los pacientes portadores de Desfibrilador Automático Implantable (DAI) de la Unidad de Electrofisiología y Arritmias del Hospital Universitario Virgen del Rocío de Sevilla.
Metodología: Estudio cualitativo mediante entrevistas semiestructuradas a 11 personas con DAI implantado. Se realizó un análisis de contenido teniendo en cuenta el objetivo de la investigación, las categorías de análisis creadas y las emergentes.
Resultados principales: Los temas identificados fueron: la experiencia de vivir con un DAI, las descargas, las estrategias de adaptación, los cambios físicos, emocionales y en el estilo de vida, la vida sexual y la prohibición de conducir.
Conclusión principal: Aunque la mayoría de los pacientes aceptan el dispositivo identificando las variables que influyen en la adaptación, existen limitaciones derivadas de cambios físicos, emocionales y en el estilo de vida. Los profesionales sanitarios han de valorar potenciales dificultades de adaptación o alteraciones psicológicas con el fin de facilitar las intervenciones necesarias.Objective: To know the experiences of patients with an Implantable Cardioverter Defibrillator in the Electrophysiology and Arrhytmia Unit (“Virgen del Rocio” University Hospital Seville). Methods: A qualitative study by using semi-structured interviews with 11 people with ICDs. A content analysis considering research objectives, analytical categories, and those possibly emerging was carried out. Results:
The identified issues were: the experience of living with an ICD, discharges, adaptation strategies, physical and emotional changes, as well as those affecting lifestyles, sex life, and driving ban. Conclusions: Although most of patients accept the device,identifying the variables affecting their adaptation, there are still some limitations resulting from physical, emotional, and lifestyle changes. Health professionals should assess potential adaptation difficulties or psychological disorders in order to provide necessary interventions
Load that maximizes power output in countermovement jump
Introduction:
One of the main problems faced by strength and conditioning coaches is the issue of how to objectively quantify and monitor the actual training load undertaken by athletes in order to maximize performance. It is well known that performance of explosive sports activities is largely determined by mechanical power.
Objective:
This study analysed the height at which maximal power output is generated and the corresponding load with which is achieved in a group of male-trained track and field athletes in the test of countermovement jump (CMJ) with extra loads (CMJEL).
Methods:
Fifty national level male athletes in sprinting and jumping performed a CMJ test with increasing loads up to a height of 16 cm. The relative load that maximized the mechanical power output (Pmax) was determined using a force platform and lineal encoder synchronization and estimating the power by peak power, average power and flight time in CMJ.
Results:
The load at which the power output no longer existed was at a height of 19.9 ± 2.35, referring to a 99.1 ± 1% of the maximum power output. The load that maximizes power output in all cases has been the load with which an athlete jump a height of approximately 20 cm.
Conclusion:
These results highlight the importance of considering the height achieved in CMJ with extra load instead of power because maximum power is always attained with the same height. We advise for the preferential use of the height achieved in CMJEL test, since it seems to be a valid indicative of an individual's actual neuromuscular potential providing a valid information for coaches and trainers when assessing the performance status of our athletes and to quantify and monitor training loads, measuring only the height of the jump in the exercise of CMJEL.Actividad Física y Deport
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