1,934 research outputs found

    Mercados de trabajo locales y desarrollo territorial sostenible

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    Una amplia tradición de científicos sociales de varios campos disciplinares están de acuerdo en definir los mercados de trabajo locales como espacios de movilidad diaria de la población por motivos de trabajo (Combes 1986; Eurostat, 1992; Casado Díaz, 1991). La cuestión que se plantea en este trabajo es si estos espacios, además de ser útiles para la gestión territorial de las políticas de empleo, pueden resultar unidades territoriales adecuadas para la concepción de políticas multidimensionales más amplias promotoras del desarrollo sostenible de los territorios que delimitan.____________________________________Social scientists from several disciplinary fields long agree that local labour markets can be defined as spaces of daily population mobility due to labour reasons (Combes 1986; Eurostat, 1992; Casado Díaz, 1991). The question we address in this paper is whether these spaces are not only useful for territorial management of employment policy, but also suitable territorial units in conceptualizing wider multidimensional politics that can facilitate sustainable territorial development

    Distinct mechanisms regulate hemocyte chemotaxis during development and wound healing in Drosophila melanogaster

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    Drosophila melanogaster hemocytes are highly motile macrophage-like cells that undergo a stereotypic pattern of migration to populate the whole embryo by late embryogenesis. We demonstrate that the migratory patterns of hemocytes at the embryonic ventral midline are orchestrated by chemotactic signals from the PDGF/VEGF ligands Pvf2 and -3 and that these directed migrations occur independently of phosphoinositide 3-kinase (PI3K) signaling. In contrast, using both laser ablation and a novel wounding assay that allows localized treatment with inhibitory drugs, we show that PI3K is essential for hemocyte chemotaxis toward wounds and that Pvf signals and PDGF/VEGF receptor expression are not required for this rapid chemotactic response. Our results demonstrate that at least two separate mechanisms operate in D. melanogaster embryos to direct hemocyte migration and show that although PI3K is crucial for hemocytes to sense a chemotactic gradient from a wound, it is not required to sense the growth factor signals that coordinate their developmental migrations along the ventral midline during embryogenesis

    Fluidization of Group B particles with a rotating distributor

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    A novel rotating distributor fluidized bed is presented. The distributor is a rotating perforated plate, with 1% open-area ratio. This work evaluates the performance of this new design, considering pressure drop, Δp, and quality of fluidization. Bed fluidization was easily achieved with the proposed device, improving the solid mixing and the quality of fluidization. In order to examine the effect of the rotational speed of the distributor plate on the hydrodynamic behavior of the bed, minimum fluidization velocity, Umf, and pressure fluctuations were analyzed. Experiments were conducted in the bubbling free regime in a 0.19 m i.d. fluidized bed, operating with Group B particles according to Geldart's classification. The pressure drop across the bed and the standard deviation of pressure fluctuations, σp, were used to find the minimum fluidization velocity, Umf. A decrease in Umf is observed when the rotational speed increases and a rise in the measured pressure drop was also found. Frequency analysis of pressure fluctuations shows that fluidization can be controlled by the adjustable rotational speed, at several excess gas velocities. Measurements with several initial static bed heights were taken, in order to analyze the influence of the initial bed mass inventory, over the effect of the distributor rotation on the bed hydrodynamics.Publicad

    Una aproximación a la educación emocional desde el marco legislativo

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    Este artículo pretende reflejar la evolución de la educación emocional a través de la ley, desde la Ley General de Educación de 1970 hasta la llegada de la LOMCE en 2013. Es un recorrido histórico sobre el uso de las emociones en educación, donde podemos observar la aparición de éstas a lo largo de las diferentes leyes educativas. El objetivo de este texto es profundizar en las leyes y reflexionar sobre la aparición de la educación emocional en el marco legislativo y su posterior puesta en escena

    Exergy Optimization of a Moving Bed Heat Exchanger

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    The MBHE proposed can be analyzed as a crossflow heat exchanger where one of the phases is a moving granular medium. In the present work the exergy analysis of the MBHE is carried out over operation data of the exchanger obtained in two ways: a numerical simulation of the stationary problem and a simplified analysis. The numerical simulation is carried over the two steady state energy equations (fluid and solid), involving (for the fluid) the convection heat transfer to the solid and the diffusion term in the flow direction, and (for the solid) only the convection heat transfer to the fluid. The simplified analysis followed the well-known e-NTU method, taking the equipment as a crossflow heat exchanger with both fluids unmixed.Publicad

    The CartoCiudad gamble on Open Source and value-added services

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    Ponencias, comunicaciones y pósters presentados en el 17th AGILE Conference on Geographic Information Science "Connecting a Digital Europe through Location and Place", celebrado en la Universitat Jaume I del 3 al 6 de junio de 2014.CartoCiudad is a seamless cartographic database all over Spain where all road network is topologically structured and connected. This database, built from data managed by public organizations, is the result of harmonization and integration of official digital cartography and information produced by the main stakeholders of Geographical Information in Spain

    ATLETAS NA EDUCAÇÃO SUPERIOR: A QUESTÃO DA PERMANÊNCIA E DA EVASÃO

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    O objetivo deste artigo é discutir a problemática da permanência e da evasão dos alunos atletas na Educação Superior. De natureza quantitativa, o estudo apoia-se em dados oficiais coletados de uma determinada Instituição de Ensino de São Paulo na qual esses alunos estão matriculados, a partir da consulta do controle de matrículas e freqüência dos atletas bolsistas ingressantes em janeiro de 2012. A discussão dos dados coletados conta com o apoio dos teóricos da área de Política Pública em Educação Superior e de estudos realizados por outros pesquisadores relacionados às políticas de acesso, permanência, evasão escolar e escolarização dos atletas. Como resultado, espera-se contribuir com as ações, programas ou projetos que visam apoiar os atletas quanto ao acesso, a permanência e a conclusão de seus estudos na educação superior

    A review: Macrophytes in the assessment of Spanish lakes ecological status under the Water Framework Directive (WFD)

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    Basándose en que los procesos de biomonitorización aportan información muy valiosa sobre los impactos en organismos y consecuentemente en el estado ecológico de los ecosistemas, la Directiva Marco del Agua (WFD; Unión Europea, 2000) incorpora el uso de indicadores biológicos y métricos para la evaluación del estado ecológico de las masas de agua. Uno de los elementos biológicos definidos en la Directiva es “Otra flora acuática” incluyendo macrófitos y fitobentos; la composición y abundancia de macrófitos debe ser estimada y evaluada en los lagos definidos como masas de agua dentro de la WFD. Los macrófitos tienen muchas de las características destacadas para ser un buen bioindicador; responden a fluctuaciones naturales de los regímenes hidrológicos, situación muy habitual en países mediterráneos, y además, podrían detectar cambios atribuibles a presiones e impactos antropogénicos. Existen dos tipos principales de evaluación basados en el uso de las comunidades de macrófitos; índices de diversidad (englobando diferentes variables) e índices basados en el estado trófico de las aguas. En la práctica, ambos sistemas convergen para la evaluación de estado ecológico en el sistema; sin embargo los índices tróficos no son capaces de desvelar suficiente información sobre otro tipo de perturbaciones, como por ejemplo cambios en el uso del suelo y cambios hidromorfológicos (HM). Los helófitos parecen ser una parte crucial de la evaluación y medición de impactos HM. En este trabajo se realiza una recopilación de información y una evaluación del contexto actual sobre el uso de macrófitos como bioindicadores del estado ecológico de los lagos. Concretamente, los principales objetivos se centran en (1) el estudio de las presiones y (2) requerimientos de los lagos de la Península Ibérica y (3) las metodologías de evaluación más eficaces para su monitorización, ya que actualmente aun no existe ningún protocolo de muestreo oficial a nivel estatal.Biomonitoring provides essential information on the impact of disturbances on living organisms and consequently on ecosystem health. Based on this assumption, the Water Framework Directive (WFD; DOCE, 2000) introduces the concept of biological indicators in the assessment of water bodies’ ecological status. One of the Biological Quality Element defined in the Directive is named as “Other aquatic flora” which includes macrophyte communities and phytobentos; therefore, Composition and abundance of macrophyte should be assessed. Macrophytes fit very well to many of the criteria listed for an “ideal” organism for water biomonitoring. Moreover, in Mediterranean countries, where hydrological regime strongly changes seasonally, macrophytes respond to natural fluctuations of the water level, but also detect abnormal variations that are caused by anthropogenic impacts and pressures. There are two main types of assessment based on macrophyte communities: diversity indices (involves different variables) and trophic indices. In practice, both approaches converge and work properly together to assess eutrophication conditions in the system. However, trophic indices are not able to reveal enough information to assess other kind of stressors such land use and hydromorphological pressures. Helophytes seem to be a key part of HM impacts assessment by measuring the helophyte parameters and changes in their composition and abundance. The work was aimed to the compilation and evaluation of the context in the use of macrophytes as bioindicator of lakes ecological status. The main objectives are the study of the disturbances and requirements of Spanish lakes and the suitability of ecological assessment methods for the monitoring of the ecological status, since, at the present, there is not an official national macrophyte sampling protocol.Departamento de biológica ambiental. Museo Nacional de Ciencias Naturales, CSIC

    Quasispecies as a matter of fact: Viruses and beyond

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    We review the origins of the quasispecies concept and its relevance for RNA virus evolution, viral pathogenesis and antiviral treatment strategies. We emphasize a critical point of quasispecies that refers to genome collectivities as the unit of selection, and establish parallels between RNA viruses and some cellular systems such as bacteria and tumor cells. We refer also to tantalizing new observations that suggest quasispecies behavior in prions, perhaps as a result of the same quantum-mechanical indeterminations that underlie protein conformation and error-prone replication in genetic systems. If substantiated, these observations with prions could lead to new research on the structure–function relationship of non-nucleic acid biological molecules
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