950 resultados para second and third order ionospheric effects


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Like other regions of the world, the EU is developing biofuels in the transport sector to reduce oil consumption and mitigate climate change. To promote them, it has adopted favourable legislation since the 2000s. In 2009 it even decided to oblige each Member State to ensure that by 2020 the share of energy coming from renewable sources reached at least 10% of their final consumption of energy in the transport sector. Biofuels are considered the main instrument to reach that percentage since the development of other alternatives (such as hydrogen and electricity) will take much longer than expected. Meanwhile, these various legislative initiatives have driven the production and consumption of biofuels in the EU. Biofuels accounted for 4.7% of EU transport fuel consumption in 2011. They have also led to trade and investment in biofuels on a global scale. This large-scale expansion of biofuels has, however, revealed numerous negative impacts. These stem from the fact that first-generation biofuels (i.e., those produced from food crops), of which the most important types are biodiesel and bioethanol, are used almost exclusively to meet the EU’s renewable 10% target in transport. Their negative impacts are: socioeconomic (food price rises), legal (land-grabbing), environmental (for instance, water stress and water pollution; soil erosion; reduction of biodiversity), climatic (direct and indirect land-use effects resulting in more greenhouse gas emissions) and public finance issues (subsidies and tax relief). The extent of such negative impacts depends on how biofuel feedstocks are produced and processed, the scale of production, and in particular, how they influence direct land use change (DLUC) and indirect land use change (ILUC) and the international trade. These negative impacts have thus provoked mounting debates in recent years, with a particular focus on ILUC. They have forced the EU to re-examine how it deals with biofuels and submit amendments to update its legislation. So far, the EU legislation foresees that only sustainable biofuels (produced in the EU or imported) can be used to meet the 10% target and receive public support; and to that end, mandatory sustainability criteria have been defined. Yet they have a huge flaw. Their measurement of greenhouse gas savings from biofuels does not take into account greenhouse gas emissions resulting from ILUC, which represent a major problem. The Energy Council of June 2014 agreed to set a limit on the extent to which firstgeneration biofuels can count towards the 10% target. But this limit appears to be less stringent than the ones made previously by the European Commission and the European Parliament. It also agreed to introduce incentives for the use of advanced (second- and third-generation) biofuels which would be allowed to count double towards the 10% target. But this again appears extremely modest by comparison with what was previously proposed. Finally, the approach chosen to take into account the greenhouse gas emissions due to ILUC appears more than cautious. The Energy Council agreed that the European Commission will carry out a reporting of ILUC emissions by using provisional estimated factors. A review clause will permit the later adjustment of these ILUC factors. With such legislative orientations made by the Energy Council, one cannot consider yet that there is a major shift in the EU biofuels policy. Bolder changes would have probably meant risking the collapse of the high-emission conventional biodiesel industry which currently makes up the majority of Europe’s biofuel production. The interests of EU farmers would have also been affected. There is nevertheless a tension between these legislative orientations and the new Commission’s proposals beyond 2020. In any case, many uncertainties remain on this issue. As long as solutions have not been found to minimize the important collateral damages provoked by the first generation biofuels, more scientific studies and caution are needed. Meanwhile, it would be wise to improve alternative paths towards a sustainable transport sector, i.e., stringent emission and energy standards for all vehicles, better public transport systems, automobiles that run on renewable energy other than biofuels, or other alternatives beyond the present imagination.

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After many meetings and long hours of negotiations, the overwhelming feeling when a deal between the EU and Turkey was struck, was one of “mission accomplished”! Faced with an unprecedented crisis and forced to appease increasingly hostile public opinions back home, EU leaders had only one objective in mind: reducing the number of migrants arriving in the EU so that order can return in the framework of EU rules. However, a closer look at the Summit Conclusions and the EU-Turkey statement leaves a bitter taste, according to Yves Pascouau. In this Commentary, he questions the feasibility of the final EU-Turkey deal, saying that it creates more problems than it solves: besides the obvious legal and practical issues, it is far from certain which member states will be willing to do their part, or whether or not the EU can come up with a strategic vision on human mobility for the future.

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Biomechanical adaptations that occur during pregnancy can lead to changes on gait pattern. Nevertheless, these adaptations of gait are still not fully understood. The purpose was to determine the effect of pregnancy on the biomechanical pattern of walking, regarding the kinetic parameters. A three-dimensional analysis was performed in eleven participants. The kinetic parameters in the joints of the lower limb during gait were compared at the end of the first, second, and third trimesters of pregnancy and in the postpartum period, in healthy pregnant women. The main results showed a reduction in the normalized vertical reaction forces, throughout pregnancy, particularly the third peak. Pregnant women showed, during most of the stance phase, medial reaction forces as a motor response to promote the body stability. Bilateral changes were observed in hip joint, with a decrease in the participation of the hip extensors and in the eccentric contraction of hip flexors. In ankle joint a decrease in the participation of ankle plantar flexors was found. In conclusion, the overall results point to biomechanical adjustments that showed a decrease of the mechanical load of women throughout pregnancy, with exception for few unilateral changes of hip joint moments.

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BACKGROUND: This study was aimed at evaluating the clinical protection, the level of Porcine circovirus type 2 (PCV2) viremia and the immune response (antibodies and IFN-γ secreting cells (SC)) in piglets derived from PCV2 vaccinated sows and themselves vaccinated against PCV2 at different age, namely at 4, 6 and 8 weeks. The cohort study has been carried out over three subsequent production cycles (replicates). At the start/enrolment, 46 gilts were considered at first mating, bled and vaccinated. At the first, second and third farrowing, dams were bled and re-vaccinated at the subsequent mating after weaning piglets. Overall 400 piglets at each farrowing (first, second and third) were randomly allocated in three different groups (100 piglets/group) based on the timing of vaccination (4, 6 or 8 weeks of age). A fourth group was kept non-vaccinated (controls). Piglets were vaccinated intramuscularly with one dose (2 mL) of a commercial PCV2a-based subunit vaccine (Porcilis® PCV). Twenty animals per group were bled at weaning and from vaccination to slaughter every 4 weeks for the detection of PCV2 viremia, humoral and cell-mediated immune responses. Clinical signs and individual treatments (morbidity), mortality, and body weight of all piglets were recorded. RESULTS: All vaccination schemes (4, 6 and 8 weeks of age) were able to induce an antibody response and IFN-γ SC. The highest clinical and virological protection sustained by immune reactivity was observed in pigs vaccinated at 6 weeks of age. Overall, repeated PCV2 vaccination in sows at mating and the subsequent higher levels of maternally derived antibodies did not significantly interfere with the induction of both humoral and cell-mediated immunity in their piglets after vaccination. CONCLUSIONS: The combination of vaccination in sows at mating and in piglets at 6 weeks of age was more effective for controlling PCV2 natural infection, than other vaccination schemas, thus sustaining that some interference of MDA with the induction of an efficient immune response could be considered. In conclusion, optimal vaccination strategy needs to balance the levels of passive immunity, the management practices and timing of infection.

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El presente texto hace referencia a mis estudios de tesina de grado los cuales me encuentro realizando para la Licenciatura Universitaria en Educación Física (LUEF) en el Departamento de Educación Física de la Facultad de Humanidades y Ciencias de la Educación (FaHCE) de la Universidad Nacional de La Plata (UNLP). Mientras transcurría el período de cursadas en el Profesorado Universitario en Educación Física (PUEF), más específicamente desde el ingreso a la carrera, he observado el problema de que los alumnos que cursan los ejes Natación 1 y 2 en las asignaturas Educación Física 2 y 3 en el segundo y tercer año del plan de estudios vigente (2000) comparado con otro plan mas antiguo (1984), gran número de cursantes desaprueban las comisiones existentes; entonces es que me pregunté: ¿cuál es el problema por el que tantos alumnos desaprueban estos ejes? En base a eso he decidido investigar sobre dicho tema, para conocer si el problema son los alumnos, los docentes, los contenidos, la teoría-práctica, los métodos de enseñanza, los saberes previos, la evaluación, etc. , es decir, los aspectos pedagógicos y didácticos en general. En función de lo desarrollado anteriormente considero que en mi tesis de grado, no podía faltar un capítulo de la historia de la Natación en la Ciudad de La Plata. Dicho capítulo es el primero de la tesina, en el cual describo en un recorrido socio-histórico la creación de la ciudad de La Plata, detallo cómo y por qué han surgido los primeros clubes deportivos con sus respectivos natatorios en la ciudad. Particularizo sobre la creación de la UNLP y cómo ha llegado el PUEF a incorporarse en la FaHCE. Y por último, relato la incorporación del el eje Natación en el plan de estudios como así mismo en las asignaturas Educación Física 2 y 3. Describir el contexto socio- histórico cultural es importante para poder comprender el motivo y las circunstancias de la incorporación de la natación en el PUEF. Metodológicamente me inclinaré por una investigación cualitativa y cuantitativa donde la recolección de datos será realizada por medio de encuestas, entrevistas y observaciones de campo. Así mismo, otro tipo de fuentes como planes de estudio, leyes o legislación, material bibliográfico, serán analizados. Para finalizar, intentaré triangular los datos relevados en el trabajo de campo con el objeto de arribar a conclusiones posibles y dar respuesta a mi interrogante

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El presente texto hace referencia a mis estudios de tesina de grado los cuales me encuentro realizando para la Licenciatura Universitaria en Educación Física (LUEF) en el Departamento de Educación Física de la Facultad de Humanidades y Ciencias de la Educación (FaHCE) de la Universidad Nacional de La Plata (UNLP). Mientras transcurría el período de cursadas en el Profesorado Universitario en Educación Física (PUEF), más específicamente desde el ingreso a la carrera, he observado el problema de que los alumnos que cursan los ejes Natación 1 y 2 en las asignaturas Educación Física 2 y 3 en el segundo y tercer año del plan de estudios vigente (2000) comparado con otro plan mas antiguo (1984), gran número de cursantes desaprueban las comisiones existentes; entonces es que me pregunté: ¿cuál es el problema por el que tantos alumnos desaprueban estos ejes? En base a eso he decidido investigar sobre dicho tema, para conocer si el problema son los alumnos, los docentes, los contenidos, la teoría-práctica, los métodos de enseñanza, los saberes previos, la evaluación, etc. , es decir, los aspectos pedagógicos y didácticos en general. En función de lo desarrollado anteriormente considero que en mi tesis de grado, no podía faltar un capítulo de la historia de la Natación en la Ciudad de La Plata. Dicho capítulo es el primero de la tesina, en el cual describo en un recorrido socio-histórico la creación de la ciudad de La Plata, detallo cómo y por qué han surgido los primeros clubes deportivos con sus respectivos natatorios en la ciudad. Particularizo sobre la creación de la UNLP y cómo ha llegado el PUEF a incorporarse en la FaHCE. Y por último, relato la incorporación del el eje Natación en el plan de estudios como así mismo en las asignaturas Educación Física 2 y 3. Describir el contexto socio- histórico cultural es importante para poder comprender el motivo y las circunstancias de la incorporación de la natación en el PUEF. Metodológicamente me inclinaré por una investigación cualitativa y cuantitativa donde la recolección de datos será realizada por medio de encuestas, entrevistas y observaciones de campo. Así mismo, otro tipo de fuentes como planes de estudio, leyes o legislación, material bibliográfico, serán analizados. Para finalizar, intentaré triangular los datos relevados en el trabajo de campo con el objeto de arribar a conclusiones posibles y dar respuesta a mi interrogante