11 research outputs found

    Comparative theoretical analysis between parallel and perpendicular geometries for 2d particle patterning in photovoltaic ferroelectric substrates

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    This paper describes the dielectrophoretic potential created by the evanescent electric field acting on a particle near a photovoltaic crystal surface depending on the crystal cut. This electric field is obtained from the steady state solution of the Kukhtarev equations for the photovoltaic effect, where the diffusion term has been disregarded. First, the space charge field generated by a small, square, light spot where d ≪ l (being d a side of the square and l the crystal thickness) is studied. The surface charge density generated in both geometries is calculated and compared as their relation determines the different properties of the dielectrophoretic potential for both cuts. The shape of the dielectrophoretic potential is obtained and compared for several distances to the sample. Afterwards other light patterns are studied by the superposition of square spots, and the resulting trapping profiles are analysed. Finally the surface charge densities and trapping profiles for different d/l relations are studiedThis work was supported by the Spanish Ministerio de Economia y Competitividad under grants MAT2011-28379- C03 and MAT2014-57704-C

    Ganho de peso vivo e fermentação ruminal em novilhos mantidos em pastagem cultivada de clima temperado e recebendo diferentes suplementos Live weight gain and ruminal fermentation by steers grazing cool-season grass pasture and given different supplements

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    Foram conduzidos dois experimentos para avaliar o ganho de peso vivo (Experimento 1) e parâmetros da fermentação ruminal (Experimento 2) em quarenta novilhos cruzados Charolês e Nelore, mantidos em pastagem cultivada de inverno, por quatro horas diárias e não suplementados, ou por somente duas horas, mas suplementados (1% do peso vivo) com silagem de planta inteira, silagem de grão úmido ou com grão seco de sorgo. Os animais alimentados somente com pastagem obtiveram os maiores ganhos de peso vivo (P<0,05) e os suplementados com silagem de planta inteira, os menores. Os suplementados com grãos, tanto secos como na forma de silagem, obtiveram ganhos de peso intermediários. As concentrações de aminoácidos e peptídeos não foram influenciadas (P>0,05) pela suplementação, as de amônia e açúcares foram maiores nos animais mantidos somente com pastagem e nos suplementados com silagem de grão úmido, e menores nos animais suplementados com silagem de planta inteira ou com grão seco de sorgo (P<0,05). Os valores de pH ruminal foram menores nos animais suplementados com silagem de grão úmido de sorgo (P<0,05). Os suplementos utilizados não melhoraram o desempenho dos animais mantidos em pastagem cultivada de clima temperado, mas a fermentação ruminal variou ao longo do dia e com o tipo de suplemento utilizado. No entanto, os resultados indicam também que, além do tipo, a adequação de horários de pastejo e de suplementação poderia representar um fator condicionante à eficiência do uso do suplemento pelos animais.<br>Two experiments to evaluate daily weight gain (Experiment 1) and ruminal fermentation parameters (Experiment 2) were carried out. Nelore and Charolais crossbreed steers grazing on cool-season pasture during four hours daily or during only two hours daily but supplemented (1% of live weight) with sorghum whole plant silage, wet grain silage or dry grain were used. Animals fed only with pasture obtained the highest and, those supplemented with whole plant silage, the lowest daily weight gain (P<0.05). Wet or dry grain supplemented steers obtained intermediary daily weight gain. Ruminal concentrations of amino acids and peptides were not affected (P>0.05) by supplementation. Ammonia and sugar concentrations were higher by animals fed only with pasture or supplemented with sorghum wet grain silage and lower by those supplemented with whole plant silage or dry grain (P<0.05). Ruminal pH values were lower by animals supplemented with sorghum wet grain silage (P<0.05). Supplements did not improve weight gain of steers grazing cool-season pasture but ruminal fermentation varied through a day and was different among supplements. Results also indicate that, besides supplement type, synchrony between grazing and supplementation schedule may represent a conditioning factor to improve feed efficiency use by animals

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    Effect of Oral Insulin on Prevention of Diabetes in Relatives of Patients With Type 1 Diabetes A Randomized Clinical Trial

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    Transplantation and autoimmunit

    Identical and Nonidentical Twins: Risk and Factors Involved in Development of Islet Autoimmunity and Type 1 Diabetes

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    Cardiovascular Aspects of Radiolog
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