422 research outputs found

    The impact of large-scale circulation patterns on summer crop in Iberian Peninsula

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    Large-scale circulations patterns (ENSO, NAO) have been shown to have a significant impact on seasonal weather, and therefore on crop yield over many parts of the world(Garnett and Khandekar, 1992; Aasa et al., 2004; Rozas and Garcia-Gonzalez, 2012). In this study, we analyze the influence of large-scale circulation patterns and regional climate on the principal components of maize yield variability in Iberian Peninsula (IP) using reanalysis datasets. Additionally, we investigate the modulation of these relationships by multidecadal patterns. This study is performed analyzing long time series of maize yield, only climate dependent, computed with the crop model CERES-maize (Jones and Kiniry, 1986) included in Decision Support System for Agrotechnology Transfer (DSSAT v.4.5)

    Dynamical influences of El Niño on maize yield in Spain

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    Climate variability and changes in the frequency of extremes events have a direct impact on crop damages and yield. In a former work of Capa et al. (2013) the crop yield variability has been studied using different reanalyses datasets with the aim of extending the time series of potential yield. The reliability of these time series have been checked using observational data. The influence of the sea surface temperature on the crop yield variability has been studied, finding a relation with El Niño phenomenon. The highest correlation between El Niño and yield was during 1960-1980. This study aims to analyse the dynamical mechanism of El Niño impacts on maize yield in Spain during 1960-1980 by comparison with atmospheric circulation patterns

    A Study of Possible Applications of the Half-Projected Hartree-Fock Method for Determining Singlet Excited States

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    The Half-Projected Hartree-Fock model (HPHF) is proposed for determining open shell singlet states. Some properties of the HPHF wave function are reviewed in order to discuss its application to determining excited states of medium size molecules. A calculation procedure similar to that of the UHF method is described. Some results for the methylene biradical and formic acid are presented. The HPHF model is found to be useful for determining the lowest excited states

    Bluetongue virus serotypes 1 and 4 in red deer, Spain

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    We studied the potential of red deer as bluetongue maintenance hosts and sentinels. Deer maintained detectable bluetongue virus (BTV) serotype 4 RNA for 1 year after the virus was cleared from livestock. However, the virus was not transmitted to yearlings. BTV serotype 1 RNA was detected in red deer immediately after its first detection in cattle.This study was funded by the Spanish Ministry of Natural, Rural and Marine Environment (RASVE 274/2007, and an agreement between Organismo AutĂłnomo de Parques Nacionales (OAPN), DirecciĂłn General de Recursos Agricolas y Ganaderos (DGRAG), and Consejo Superior de Investigaciones Cientificas (CSIC). F.R.-F. is supported by a postdoctoral contract of the Instituto de Salud Carlos III of the Spanish government.Peer Reviewe

    Atomic excitations during the nuclear {\ss}- decay in light atoms

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    Probabilities of various final states are determined numerically for a number of {\ss}- decaying light atoms. In our evaluations of the final state probabilities we have used the highly accurate atomic wave functions constructed for each few-electron atom/ion. We also discuss an experimental possibility to observe negatively charged ions which form during the nuclear {\ss}+ decays. High order corrections to the results obtained for {\ss}+/- decays in few-electron atoms with the use of sudden approximation are considered.Comment: 26 pages, 40 references, 6 tables and 0 figure

    Assessing methods for developing crop forecasting in the Iberian Peninsula

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    Seasonal climate prediction may allow predicting crop yield to reduce the vulnerability of agricultural production to climate variability and its extremes. It has been already demonstrated that seasonal climate predictions at European (or Iberian) scale from ensembles of global coupled climate models have some skill (Palmer et al., 2004)

    Linking seasonal climate forecasts with crop models in Iberian Peninsula

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    Translating seasonal climate forecasts into agricultural production forecasts could help to establish early warning systems and to design crop management adaptation strategies that take advantage of favorable conditions or reduce the effect of adverse conditions. In this study, we use seasonal rainfall forecasts and crop models to improve predictability of wheat yield in the Iberian Peninsula (IP). Additionally, we estimate economic margins and production risks associated with extreme scenarios of seasonal rainfall forecast

    Porous titanium substrates coated with a bilayer of bioactive glasses

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    Porous titanium substrates coated by dripping-sedimentation technique with a novel bilayer of (45S5 / 1393) bioactive glasses are proposed to overcome some limitations of the use of titanium for implants, such as the stress shielding and the poor osseointegration. Composition, thickness, roughness and micromechanical behavior (P-h curves) of the coating and the influence of the porous titanium substrates have been characterized. Best results were found for the substrate with 30 vol.% of porosity and a range size of 355 ‒ 500 μm, since it enhanced the mechanical and biofunctional behavior, due to the good adhesion of the 1393 bioglass to the substrate and the greater bioactivity of the 45S5 bioglass, which would be in contact with the bone.Junta de Andalucía–FEDER (Spain) US-1259771M.E.C. (Spain) 2004/00001203 (RYC-2004-001497
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