40 research outputs found

    Comparison of the Spherical Averaged Pseudopotential Model with the Stabilized Jellium Model

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    We compare Kohn-Sham results (density, cohesive energy, size and effect of charging) of the Spherical Averaged Pseudopotential Model with the Stabilized Jellium Model for clusters of sodium and aluminum with less than 20 atoms. We find that the Stabilized Jellium Model, although conceptually and practically more simple, gives better results for the cohesive energy and the elastic stiffness. We use the Local Density Approximation as well as the Generalized Gradient Approximation to the exchange and correlation energies.Comment: 13 pages, latex, 8 figures, compressed postscript version available at http://www.fis.uc.pt/~vieir

    Conductas adictivas y trastorno por déficit de atención con hiperactividad en adultos

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    El trastorno por déficit de atención con hiperactividad (TDAH) es un trastorno de inicio en la infancia, con una prevalencia del 1.2 7.3% en población general adulta. La frecuencia de trastornos comórbidos es elevada en los pacientes con TDAH. Las conductas adictivas o trastornos por uso de sustancias (TUS) son de los que mayor relevancia tienen en este sentido. La comorbilidad TDAH y TUS destaca por las dificultades diagnósticas, terapéuticas y de pronóstico que puede significar su asociación. Los psicoestimulantes, como el metilfenidato, son el tratamiento de primera elección en pacientes con TDAH. A pesar de ello, existen controversias sobre el uso de este tipo de medicamentos en pacientes con patología dual. Los resultados de los ensayos clínicos realizados en esta población específica, indican que son fármacos seguros y eficaces en el manejo de los síntomas del TDAH. Los estudios no han despejado la duda si pueden ser fármacos útiles en la evolución del consumo de tóxicos, aunque sí han demostrado que no incrementan la drogodependencia de base

    EcoAnchoa-Asturias 2011 Actividades realizadas por el Instituto Español de Oceanografía e informe de resultados

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    Resumen Las condiciones hidrográficas observadas durante la campaña Pelacus0411, realizada entre el 26 de marzo y 20 de Abril de 2011 en aguas de la plataforma continental Nord Ibérica, son las propias de comienzos de primavera, caracterizadas por una incipiente estratificación térmica y la presencia de agua de baja salinidad cerca de la costa, principalmente en las proximidades de las desembocaduras de los principales ríos. La fluorescencia (variable indicadora de la abundancia de fitoplancton –producción primaria) presentó los valores más elevados en superficie sobre el talud continental en la zona de Galicia, influenciada por la masa de agua de alta salinidad asociada a la contracorriente de talud (‘Corriente Ibérica hacia el Polo’). A partir del Cantábrico Central, frente a la costa Asturiana, y hacia la zona interna del Golfo de Vizcaya, se observó un máximo sub-superficial de clorofila entorno a los 20 o 30 m. La biomasa total de sardina en la zona de estudio estimada mediante métodos acústicos fue de 11.768 toneladas (t) (151106 individuos). Esta especie se localizó preferentemente en la plataforma de Asturias (sub-área ICES VIIIcE-w), en contraste con su práctica ausencia en aguas de la plataforma de Gallicia (sub-áreas ICES IXa-N y VIIIcW). Los individuos más jóvenes, de edades entre 1 y 2 años, predominaron en Galicia (sub-área ICES IXaN), mientras que los de mayor edad, 3 años, fueron más abundantes en la plataforma de Asturias y del País Vasco (sub-áreas ICES VIIIcE-w y VIIIcE-e respectivamente). Las estimas de abundancia de sardina en la campaña de 2011 son las más bajas de la serie desde 2001 y suponen un motivo de preocupación en relación al estado del stock. Si no tiene lugar un reclutamiento importante, el último de los cuales tuvo lugar en 2004, la previsión apunta hacia un descenso continuado de la biomasa de sardina en la plataforma Nord Ibérica. La biomasa estimada de anchoa fue de 2071 t, correspondiente a 142000 individuos. Éstos se localizaron en dos zonas separadas: al sur de Galicia (sub-área ICES IXa-N) y la parte interna del Golfo de Vizcaya (País Vasco y frontera con Francia; ICES sub-área VIIIcE-e y sub-división ICES VIIIb respectivamente), donde predominaron los individuos recién incorporados a la pesquería (i.e. 1 año de edad). Tanto la biomasa como el área ocupada por anchoa son superiores a las registradas en años anteriores. En contraste con la situación de los adultos, los datos proporcionados por la CUFES (muestreados en continuo de huevos de peces) indicaron que los huevos de sardina se localizaron en 6 toda el área prospectada en número similar a los encontrados en la campaña del año anterior, si bien más cerca de costa. Respecto a anchoa, se ha observado un incremento significativo tanto de la abundancia y extensión del área de distribución de huevos, más allá de la tradicional zona de presencia localizada en la parte interna del Golfo de Vizcaya.Consejería de Medio Rural y pesca del Principado de Asturias, Instituto Español de Oceanografí

    HABs in coastal upwelling systems: Insights from an exceptional red tide of the toxigenic dinoflagellate Alexandrium minutum

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    Alexandrium minutum blooms generally occur in semi-enclosed sites such as estuaries, harbours and lagoons, where enhanced stratification, restricted circulation and accumulation of resting cysts in the sediment set suitable habitat conditions for the proliferation of this paralytic shellfish poisoning toxigenic species. In the Galician Rías Baixas (NW Iberian Peninsula), according to weekly time-series between 1994 and 2020, blooms of A. minutum were recurrent in small, shallow estuarine bays inside the Rías de Vigo and Pontevedra, but rarely detected, and if so at low concentrations, out of these environments. However, from May to July 2018 it developed as usual in the small inner bays but then spread over both Rías (Vigo and Pontevedra) causing discoloured waters during one month and prolonged harvesting closures. Meteorological conditions during that period (rains / runoff higher than climatological averages, sustained temperature increment and oscillating wind pattern –i.e., series of upwelling-relaxation cycles), fostered optimal circumstances for the development of that extensive and massive proliferation: strong vertical stratification and the alternation of retention and dispersion processes. Simulations from a particle tracking model portrayed the observed bloom development phases: onset and development inside a small inner bay; transport within the surface layer, from these sites towards the interior parts of the Ría; and dispersion all over the embayment. Seedbeds with high concentrations of resting cysts were detected several months after the bloom, which may have favoured flourishment of A. minutum in the following two years, markedly in 2020. The present work contributes to the general understanding of the dynamics of harmful algal blooms (HABs), from which surveillance indicators of the state of marine ecosystems and their evolution can be derived. We hypothesize that the intensity and frequency of A. minutum proliferations in the Galician Rías could increase under projected climate trends.Postprint2,69

    Bloom dynamics of an exceptional red tide of the toxigenic dinoflagellate

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    The toxic dinoflagellate Alexandrium minutum generally proliferates in semi-enclosed sites such as estuaries, harbours and lagoons, where stratification, restricted circulation and accumulation of resting cysts set suitable conditions for its development. In the Galician Rías (NW Iberian Peninsula), its blooms follow also this pattern. They are recurrent in small, shallow estuarine bays inside the Rías, but rarely detected, and if so in minor amount, out of these areas. However, a massive proliferation of A. minutum from June to July 2018 in the Rías Baixas (Vigo and Pontevedra) changed this picture. The bloom initiated in semi-enclosed waters, as previously described for this species, but thereafter spread to the whole embayments where persisted more than one month. It generated a noticeable red tide with disperse patches that became heavily concentrated inside the port of Vigo. During that period shellfish harvesting closures and paralytic shellfish toxins in certain marine invertebrates and fish were reported for the first time in Spain. Meteorological conditions (higher than usual rains/runoff, sustained temperature increment and oscillating wind pattern promoting a series of upwelling-relaxation cycles) fostered optimal circumstances for the outbreak of A. minutum: strong vertical stratification and the alternation of retention and dispersion processes. Simulations from a particle tracking model portrayed the observed bloom development phases: onset, transport within the surface layer towards the interior parts of the Ría of Vigo, and dispersion all over the embayment. High concentrations of resting cysts were detected several months after the bloom, which may have favoured flourish of A. minutum in the following years, markedly in 2020

    Bloom dynamics of an exceptional red tide of the toxigenic dinoflagellate

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    19th International Conference on Harmful Algae, october 10-15The toxic dinoflagellate Alexandrium minutum generally proliferates in semi-enclosed sites such as estuaries, harbours and lagoons, where stratification, restricted circulation and accumulation of resting cysts set suitable conditions for its development. In the Galician Rías (NW Iberian Peninsula), its blooms follow also this pattern. They are recurrent in small, shallow estuarine bays inside the Rías, but rarely detected, and if so in minor amount, out of these areas. However, a massive proliferation of A. minutum from June to July 2018 in the Rías Baixas (Vigo and Pontevedra) changed this picture. The bloom initiated in semi-enclosed waters, as previously described for this species, but thereafter spread to the whole embayments where persisted more than one month. It generated a noticeable red tide with disperse patches that became heavily concentrated inside the port of Vigo. During that period shellfish harvesting closures and paralytic shellfish toxins in certain marine invertebrates and fish were reported for the first time in Spain. Meteorological conditions (higher than usual rains/runoff, sustained temperature increment and oscillating wind pattern promoting a series of upwelling-relaxation cycles) fostered optimal circumstances for the outbreak of A. minutum: strong vertical stratification and the alternation of retention and dispersion processes. Simulations from a particle tracking model portrayed the observed bloom development phases: onset, transport within the surface layer towards the interior parts of the Ría of Vigo, and dispersion all over the embayment. High concentrations of resting cysts were detected several months after the bloom, which may have favoured flourish of A. minutum in the following years, markedly in 2020.N

    HABs in coastal upwelling systems: Insights from an exceptional red tide of the toxigenic dinoflagellate Alexandrium minutum

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    14 pages, 8 figures, 1 table.-- Under a Creative Commons licenseAlexandrium minutum blooms generally occur in semi-enclosed sites such as estuaries, harbours and lagoons, where enhanced stratification, restricted circulation and accumulation of resting cysts in the sediment set suitable habitat conditions for the proliferation of this paralytic shellfish poisoning toxigenic species. In the Galician Rías Baixas (NW Iberian Peninsula), according to weekly time-series between 1994 and 2020, blooms of A. minutum were recurrent in small, shallow estuarine bays inside the Rías de Vigo and Pontevedra, but rarely detected, and if so at low concentrations, out of these environments. However, from May to July 2018 it developed as usual in the small inner bays but then spread over both Rías (Vigo and Pontevedra) causing discoloured waters during one month and prolonged harvesting closures. Meteorological conditions during that period (rains / runoff higher than climatological averages, sustained temperature increment and oscillating wind pattern –i.e., series of upwelling-relaxation cycles), fostered optimal circumstances for the development of that extensive and massive proliferation: strong vertical stratification and the alternation of retention and dispersion processes. Simulations from a particle tracking model portrayed the observed bloom development phases: onset and development inside a small inner bay; transport within the surface layer, from these sites towards the interior parts of the Ría; and dispersion all over the embayment. Seedbeds with high concentrations of resting cysts were detected several months after the bloom, which may have favoured flourishment of A. minutum in the following two years, markedly in 2020. The present work contributes to the general understanding of the dynamics of harmful algal blooms (HABs), from which surveillance indicators of the state of marine ecosystems and their evolution can be derived. We hypothesize that the intensity and frequency of A. minutum proliferations in the Galician Rías could increase under projected climate trendsThis work was funded by the Spanish national project DIANAS (CTM2017-86066-R, MICINN) and CCVIEO (Instituto Español de Oceanografía). PD-T was supported by the Xunta de Galicia program “Talento Senior” (N° contract 03 IN858A 2019 1630129) with additional funds of the Axencia Galega de Innovacion (agreement GAIN-IEO)Peer reviewe

    Host adaptive immunity deficiency in severe pandemic influenza

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    INTRODUCTION: Pandemic A/H1N1/2009 influenza causes severe lower respiratory complications in rare cases. The association between host immune responses and clinical outcome in severe cases is unknown. METHODS: We utilized gene expression, cytokine profiles and generation of antibody responses following hospitalization in 19 critically ill patients with primary pandemic A/H1N1/2009 influenza pneumonia for identifying host immune responses associated with clinical outcome. Ingenuity pathway analysis 8.5 (IPA) (Ingenuity Systems, Redwood City, CA) was used to select, annotate and visualize genes by function and pathway (gene ontology). IPA analysis identified those canonical pathways differentially expressed (P < 0.05) between comparison groups. Hierarchical clustering of those genes differentially expressed between groups by IPA analysis was performed using BRB-Array Tools v.3.8.1. RESULTS: The majority of patients were characterized by the presence of comorbidities and the absence of immunosuppressive conditions. pH1N1 specific antibody production was observed around day 9 from disease onset and defined an early period of innate immune response and a late period of adaptive immune response to the virus. The most severe patients (n = 12) showed persistence of viral secretion. Seven of the most severe patients died. During the late phase, the most severe patient group had impaired expression of a number of genes participating in adaptive immune responses when compared to less severe patients. These genes were involved in antigen presentation, B-cell development, T-helper cell differentiation, CD28, granzyme B signaling, apoptosis and protein ubiquitination. Patients with the poorest outcomes were characterized by proinflammatory hypercytokinemia, along with elevated levels of immunosuppressory cytokines (interleukin (IL)-10 and IL-1ra) in serum. CONCLUSIONS: Our findings suggest an impaired development of adaptive immunity in the most severe cases of pandemic influenza, leading to an unremitting cycle of viral replication and innate cytokine-chemokine release. Interruption of this deleterious cycle may improve disease outcome.The study was scientifically sponsored by the Spanish Society for Critical Care Medicine (SEMICYUC). Funding: MICCIN-FIS/JCYL-IECSCYL-SACYL (Spain): Programa de Investigación Comisionada en Gripe, GR09/0021-EMER07/050- PI081236-RD07/0067. CIHR-NIH-Sardinia Recherché-LKSF Canada support DJK.S

    Modelización espacial de la distribución de cetáceos en el norte de la Península Ibérica: la importancia de incluir información de sus presas

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    Con el fin de identificar áreas ecológicamente significativas, necesitamos relacionar la distribución de especies con descriptores ecológicos que nos ayuden a comprender su distribución. En el medio marino, los modelos de distribución de especies (MDE) han sido tradicionalmente desarrollado en base a descriptores ecológicos indirectos (como clorofila y temperatura superficial del mar) recogidos a través de imágenes de satélite. Aunque las especies marinas pueden utilizar estas señales ambientales para localizar sus presas, el uso de información sobre la distribución de las mismas sería más informativo que el uso de estos descriptores indirectos. Gracias a las campañas oceanográficas multidisciplinares se puede recoger información simultánea de varios niveles tróficos, desde el plancton a los depredadores marinos, incluyendo sus principales presas pelágicas: los pequeños peces pelágicos. Por lo tanto, la inclusión de esta información en los MDE debería ser más relevante que las variables oceanográficas indirectas. Para testar esta hipótesis, desarrollamos MDE para las tres especies más abundantes de cetáceos que se registran en el norte de la Península Ibérica durante las campañas de primavera del Instituto Español de Oceanografía, PELACUS (2007-2013). Estas especies fueron el delfín común Delphinus delphis, el delfín mular Tursiops truncatus y el calderón común Globicephala melas. Dependiendo de las especies consideradas, se identificaron diferentes variables ambientales como importantes a la hora de explicar los patrones de distribución; pero las cifras globales ponen de manifiesto la principal contribución de la batimetría, seguido de la temperatura superficial del mar y la variabilidad espacial en la distribución de los pequeños peces pelágicos. Estos resultados tienen importantes implicaciones en reconocer la importancia de los estudios oceanográficos multidisciplinares para la obtención de descriptores ecológicos directos para mejorar los modelos de distribución de depredadores marinos
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