875 resultados para Carmen de Burgos


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The design and development of a plastic optical fiber (POF) macrobend temperature sensor is presented. The sensor has a linear response versus temperature at a fixed bend radius, with a sensitivity of 1.92.10(-3) (degrees C)(-1). The sensor system used a dummy fiber-optic sensor for reference purposes having a resolution below 0.3 degrees C. A comprehensive experimental analysis was carried out to provide insight into the effect of different surrounding media on practical macro-bend POF sensor implementation. Experimental results are successfully compared with bend loss calculations.

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6 p. [+ 7 p. Supplementary Information]

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Climate change is an important environmental problem and one whose economic implications are many and varied. This paper starts with the presumption that mitigation of greenhouse gases is a necessary policy that has to be designed in a cost effective way. It is well known that market instruments are the best option for cost effectiveness. But the discussion regarding which of the various market instruments should be used, how they may interact and what combinations of policies should be implemented is still open and very lively. In this paper we propose a combination of instruments: the marketable emission permits already in place in Europe for major economic sectors and a CO(2) tax for economic sectors not included in the emissions permit scheme. The study uses an applied general equilibrium model for the Spanish economy to compute the results obtained with the new mix of instruments proposed. As the combination of the market for emission permits and the CO(2) tax admits different possibilities that depend on how the mitigation is distributed among the economic sectors, we concentrate on four possibilities: cost-effective, equalitarian, proportional to emissions, and proportional to output distributions. Other alternatives to the CO(2) tax are also analysed (tax on energy, on oil and on electricity). Our findings suggest that careful, well designed policies are needed as any deviation imposes significant additional costs that increase more than proportionally to the level of emissions reduction targeted by the EU.

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The synthesis of a GSK 2(nd) generation inhibitor of the hepatitis C virus, by enantioselective 1,3-dipolar cycloaddition between a leucine derived iminoester and tert-butyl acrylate, was studied. The comparison between silver(I) and gold(I) catalysts in this reaction was established by working with chiral phosphoramidites or with chiral BINAP. The best reaction conditions were used for the total synthesis of the hepatitis C virus inhibitor by a four step procedure affording this product in 99% ee and in 63% overall yield. The origin of the enantioselectivity of the chiral gold(I) catalyst was justified according to DFT calculations, the stabilizing coulombic interaction between the nitrogen atom of the thiazole moiety and one of the gold atoms being crucial.

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Background: The aim of this study is to examine the influence of the catechol-O-methyltranferase (COMT) gene (polymorphism Val158 Met) as a risk factor for Alzheimer's disease (AD) and mild cognitive impairment of amnesic type (MCI), and its synergistic effect with the apolipoprotein E gene (APOE). A total of 223 MCI patients, 345 AD and 253 healthy controls were analyzed. Clinical criteria and neuropsychological tests were used to establish diagnostic groups. The DNA Bank of the University of the Basque Country (UPV-EHU) (Spain) determined COMT Val158 Met and APOE genotypes using real time polymerase chain reaction (rtPCR) and polymerase chain reaction (PCR), and restriction fragment length polymorphism (RFLPs), respectively. Multinomial logistic regression models were used to determine the risk of AD and MCI. Results: Neither COMT alleles nor genotypes were independent risk factors for AD or MCI. The high activity genotypes (GG and AG) showed a synergistic effect with APOE epsilon 4 allele, increasing the risk of AD (OR = 5.96, 95% CI 2.74-12.94, p < 0.001 and OR = 6.71, 95% CI 3.36-13.41, p < 0.001 respectivily). In AD patients this effect was greater in women. In MCI patients such as synergistic effect was only found between AG and APOE epsilon 4 allele (OR = 3.21 95% CI 1.56-6.63, p = 0.02) and was greater in men (OR = 5.88 95% CI 1.69-20.42, p < 0.01). Conclusion: COMT (Val158 Met) polymorphism is not an independent risk factor for AD or MCI, but shows a synergistic effect with APOE epsilon 4 allele that proves greater in women with AD.

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A novel self-referencing fiber optic intensity sensor based on bending losses of a partially polished polymer optical fiber (POF) coupler is presented. The coupling ratio (K) depends on the external liquid in which the sensor is immersed. It is possible to distinguish between different liquids and to detect their presence. Experimental results for the most usual liquids found in industry, like water and oil, are given. K value increases up to 10% from the nominal value depending on the liquid. Sensor temperature dependence has also been studied for a range from 25 degrees C (environmental condition) to 50 degrees C. Any sector requiring liquid level measurements in flammable atmospheres can benefit from this intrinsically safe technology.

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209 p. : il., gráf.

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La infección vírica causada por el virus gripal o influenza representa una importante carga de enfermedad a nivel mundial y es responsable de una elevada morbilidad y mortalidad especialmente en ciertos grupos de riesgo. La vacunación constituye un elemento fundamental y es la principal medida preventiva para hacer frente a la gripe y sus complicaciones. El personal sanitario puede actuar como agente transmisor de la infección nosocomial, por este motivo se encuentra incluido en los grupos de riesgo en los que la vacunación frente a la gripe está indicada anualmente siempre y cuando no presente contraindicaciones. Dada su relevancia, se realizó una revisión bibliográfica, en las principales bases de datos electrónicas, para conocer la cobertura de vacunación antigripal (estacional y pandémica) del personal sanitario de España así como analizar las estrategias adoptadas con el fin de aumentar la cobertura de vacunación. La cobertura de vacunación de los profesionales sanitarios de España es baja, siendo menor para la gripe A (H1N1) que para la gripe estacional. Entre el colectivo de profesionales, los médicos tienen mayor cobertura seguido del personal de enfermería. El principal motivo para vacunarse es la autoprotección así como evitar el contagio de sus pacientes, y para no vacunarse dudar sobre la seguridad de la vacuna. La falta de información acerca de estrategias para aumentar la cobertura antigripal y la baja cobertura de este colectivo hacen necesario el desarrollo de más estudios para poder determinar el diseño e intervenciones de las campañas de vacunación antigripal.

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Boeckx C., M.C. Horno & J.L. Mendívil (Eds.)

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Este Proyecto de Fin de Carrera ha sido realizado en colaboración con la empresa Ultra-Lab y el centro Arteleku y trata sobre el diseño, desarrollo e implementación de una interfaz visual para la creación, manipulación, transformación y visualización de diferentes figuras en un entorno 3D. Estas herramientas visuales dan soporte al usuario para que este pueda realizar múltiples modificaciones de las figuras con las que está trabajando de una forma fácil, intuitiva y eficiente.