306 research outputs found

    Current ozone levels threaten gross primary production and yield of Mediterranean annual pastures and nitrogen modulates the response

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    Pastures are among the most important ecosystems in Europe considering their biodiversity and dis- tribution area. However, their response to increasing tropospheric ozone (O 3 ) and nitrogen (N) deposi- tion, two of the main drivers of global change, is still uncertain. A new Open-Top Chamber (OTC) experiment was performed in central Spain, aiming to study annual pasture response to O 3 and N in close to natural growing conditions. A mixture of six species of three representative families was sowed in the fi eld. Plants were exposed for 40 days to four O 3 treatments: fi ltered air, non- fi ltered air (NFA) repro- ducing ambient levels and NFA supplemented with 20 and 40 nl l � 1 O 3 . Three N treatments were considered to reach the N integrated doses of “ background ” , þ 20 or þ 40 kg N ha � 1 . Ozone signi fi cantly reduced green and total aboveground biomass (maximum reduction 25%) and increased the senescent biomass (maximum increase 40%). Accordingly, O 3 decreased community Gross Primary Production due to both a global reduction of ecosystem CO 2 exchange and an increase of ecosystem respiration. Nitrogen could partially counterbalance O 3 effects on aboveground biomass when the levels of O 3 were moderate, but at the same time O 3 exposure reduced the fertilization effect of higher N availability. Therefore, O 3 must be considered as a stress factor for annual pastures in the Mediterranean areas

    ¿Existe una personalidad jaquecosa?.

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    Se revisa brevemente el concepto actual de jaqueca y se analiza detalladamente la literatura existente sobre la personalidad jaquecosa. El concepto de personalidad jaquecosa fue mantenido por clínicos y autores de orientación psicoanalítica en las décadas de 1930-1950. los estudios recientes efectuados con criterios epidemiológicos (no basados en estudios hospitalarios) y realizados, empleando tests psicológicos estandarizados no son concordantes con la existencia de una personalidad jaquecosa

    ¿Existe una personalidad jaquecosa?.

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    Se revisa brevemente el concepto actual de jaqueca y se analiza detalladamente la literatura existente sobre la personalidad jaquecosa. El concepto de personalidad jaquecosa fue mantenido por clínicos y autores de orientación psicoanalítica en las décadas de 1930-1950. los estudios recientes efectuados con criterios epidemiológicos (no basados en estudios hospitalarios) y realizados, empleando tests psicológicos estandarizados no son concordantes con la existencia de una personalidad jaquecosa

    Crystalline silicon solar cells beyond 20% efficiency

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    —This paper describes a fabrication process to obtain high efficiency c-Si cells (> 20%) based on the Laser Fired Contact Passivated Emitter Rear Cell (LFC-PERC) concept. Photovoltaic efficiencies beyond 20% have been achieved using thermal SiO2 as a rear passivation layer on 2 cm x 2 cm solar cells with 0.45 cm Fz c-Si substrates. Efficiencies up to 22% are expected for material resistivities in the 0.4–5 cm using an optimized rear contact gridPostprint (published version

    How to Assess Diabetic Kidney Disease Progression? From Albuminuria to GFR

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    Malaltia renal crònica; Diabetis mellitus; Malaltia renal diabèticaEnfermedad renal crónica; Diabetes mellitus; Enfermedad renal diabéticaChronic kidney disease; Diabetes mellitus; Diabetic kidney diseaseDiabetic kidney disease (DKD) is one of the most relevant complications of type 2 diabetes and dramatically increases the cardiovascular risk in these patients. Currently, DKD is severely infra-diagnosed, or its diagnosis is usually made at advanced stages of the disease. During the last decade, new drugs have demonstrated a beneficial effect in terms of cardiovascular and renal protection in type 2 diabetes, supporting the crucial role of an early DKD diagnosis to permit the use of new available therapeutic strategies. Moreover, cardiovascular and renal outcome trials, developed to study these new drugs, are based on diverse cardiovascular and renal simple and composite endpoints, which makes difficult their interpretation and the comparison between them. In this article, DKD diagnosis is reviewed, focusing on albuminuria and the recommendations for glomerular filtration rate measurement. Furthermore, cardiovascular and renal endpoints used in classical and recent cardiovascular outcome trials are assessed in a pragmatic way.The authors are current recipients of research grants from the Fondo de Investigación Sanitaria-Feder—Instituto de Salud Carlos III (PI17/00257) and REDinREN (RD16/0009/0030)
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