11 resultados para Pollution prevention.


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[ES]En la problemática medioambiental generada por la contaminación atmosférica hay tres aspectos que marcan las directrices de actuación institucional: la presión social, la legislación vigente y la tecnología disponible. En cuanto a este último aspecto, la biofiltración es una tecnología eficaz, asequible y sostenible basada en la actividad biodegradadora de microorganismos específicos adheridos a la superficie de un material soporte que constituye el lecho del biofiltro. La elección de un material soporte adecuado es de especial importancia para asegurar el correcto funcionamiento de los biofiltros. Esta decisión está basada en las propiedades intrínsecas del material que deben ser analizadas previamente a su uso. En este proyecto se ha seleccionado cuales son estas propiedades básicas a partir de una revisión bibliográfica, destacando la capacidad de retención de humedad, superficie específica, porosidad, y estabilidad física y química del material. En este trabajo, también se han fijado los parámetros de control que deben ser medidos de forma rutinaria en un biofiltro para asegurar la eficacia del tratamiento de descontaminación. En base a la información bibliográfica recopilada, se ha concluido que los parámetros básicos son pH, temperatura, contenido de humedad del lecho y pérdidas de carga. A nivel experimental, se han medido las pérdidas de carga generadas en biofiltros empacados con tres materiales soportes que son de especial interés para una investigación posterior a desarrollar por el grupo Biofiltración de la Universidad del País Vasco (UPV/EHU). Durante el período de arranque inicial de los tres biofiltros, las pérdidas de carga medidas fueron muy bajas en los tres casos, aunque algo superiores cuando la alimentación era en sentido ascendente frente al flujo descendente. Sin embargo, cuando se midieron las pérdidas de carga bajo condiciones de encharcamiento del lecho, que es una de las situaciones más problemáticas en un biofiltro, todos los soportes presentaron un aumento puntual de la pérdida de carga aunque la tendencia en los días posteriores fue claramente descendente, recuperando valores de operación habituales. La comparativa del comportamiento frente a las pérdidas de carga permitió seleccionar el soporte más idóneo de los tres analizados, aunque los otros dos podrían ser alternativas viables en caso de sustitución.

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Revised 2008-08.-- Published as an article in: Journal of Public Economic Theory (2008), 10(4), 563-594.

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This paper studies the macroeconomic effects of a permanent increase in foreign aid in a model that takes into account environmental quality. We develop a dynamic equilibrium model in which both public investment in infrastructure and environmental protection can be financed using domestic resources and international aid programs. The framework considers four scenarios for international aid: untied aid,aid fully tied to infrastructure, aid fully tied to abatement, and aid equally tied to both types of expenditures. We find that the effects of the transfers may depend on (i) the structural characteristics of the recipient country (the elasticity of substitution in production and its dependence on environment and natural resources) and on (ii) how recipient countries distribute their public expenditure. These results underscore the importance of these factors when deciding how and to what extent to tie aid to infrastructure and/or pollution abatement.

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4 p.

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Purpose. To review the proposed pathogenic mechanisms of age macular degeneration (AMD), as well as the role of antioxidants (AOX) and omega-3 fatty acids (omega-3) supplements in AMD prevention. Materials and Methods. Current knowledge on the cellular/molecular mechanisms of AMD and the epidemiologic/experimental studies on the effects of AOX and omega-3 were addressed all together with the scientific evidence and the personal opinion of professionals involved in the Retina Group of the OFTARED (Spain). Results. High dietary intakes of omega-3 and macular pigments lutein/zeaxanthin are associated with lower risk of prevalence and incidence in AMD. The Age-Related Eye Disease study (AREDS) showed a beneficial effect of high doses of vitamins C, E, beta-carotene, and zinc/copper in reducing the rate of progression to advanced AMD in patients with intermediate AMD or with one-sided late AMD. The AREDS-2 study has shown that lutein and zeaxanthin may substitute beta-carotene because of its potential relationship with increased lung cancer incidence. Conclusion. Research has proved that elder people with poor diets, especially with low AOX and omega-3 micronutrients intake and subsequently having low plasmatic levels, are more prone to developing AMD. Micronutrient supplementation enhances antioxidant defense and healthy eyes and might prevent/retard/modify AMD.

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In recent decades, numerous studies have shown a significant increase in violence during childhood and adolescence. These data suggest the importance of implementing programs to prevent and reduce violent behavior. The study aimed to design a program of emotional intelligence (El) for adolescents and to assess its effects on variables related to violence prevention. The possible differential effect of the program on both genders was also examined. The sample comprised 148 adolescents aged from 13 to 16 years. The study used an experimental design with repeated pretest-posttest measures and control groups. To measure the variables, four assessment instruments were administered before and after the program, as well as in the follow-up phase (1 year after the conclusion of the intervention). The program consisted of 20 one-hour sessions. The pretest-posttest ANCOVAs showed that the program significantly increased: (1) El (attention, clarity, emotional repair); (2) assertive cognitive social interaction strategies; (3) internal control of anger; and (4) the cognitive ability to analyze negative feelings. In the follow-up phase, the positive effects of the intervention were generally maintained and, moreover, the use of aggressive strategies as an interpersonal conflict-resolution technique was significantly reduced. Regarding the effect of the program on both genders, the change was very similar, but the boys increased assertive social interaction strategies, attention, and emotional clarity significantly more than the girls. The importance of implementing programs to promote socio-emotional development and prevent violence is discussed.