994 resultados para 611.33


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Ce(0.65)Fe(0.33)Pt(0.02)O(2-delta) and Ce(0.67)Fe(0.33)O(2-delta) have been synthesized by a new low temperature sonochemical method using diethylenetriamine as a complexing agent. Due to the substitution of Fe and Pt ions in CeO(2), lattice oxygen is activated in Ce(0.67)Fe(0.33)O(2-delta) and Ce(0.65)Fe(0.33)Pt(0.02)O(2-delta). Hydrogen uptake studies show strong reduction peaks at 125 C in Ce(0.65)Fe(0.33)Pt(0.02)O(2-delta) against a hydrogen uptake peak at 420 degrees C in Ce(0.67)Fe(0.33)O(2-delta). Fe substituted ceria, Ce(0.67)Fe(0.33)O(2-delta) itself acts as a catalyst for CO oxidation and water gas shift (WGS) reactions at moderate temperatures. The rate of CO conversion in WGS with Pt free Ce(0.65)Fe(0.33)O(2-delta) is 2.8 mu mol g(-1) s(-1) at 450 C and with Pt substituted Ce(0.65)Fe(0.33)Pt(0.02)O(2-delta) is 4.05 mu mol g(-1) s(-1) at 275 degrees C. Due to the synergistic interaction of the Pt ion with Ce and Fe ions in Ce(0.65)Fe(0.33)Pt(0.02)O(2-delta), the catalyst showed much higher activity for CO oxidation and WGS reactions compared to Ce(0.67)Fe(0.33)O(2-delta). A reverse WGS reaction does not occur over Ce(0.65)Fe(0.33)Pt(0.02)O(2-delta). The catalyst also does not deactivate even when operated for a long time. Nearly 100% conversion of CO to CO(2) with 100% H(2) selectivity is observed in WGS reactions even up to 550 degrees C. (C) 2011 Elsevier B.V. All rights reserved.

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A comparative morphological study of different ZnO nanostructures was carried out with different varying process parameters for energy harvesting. Molarity, temperature, growth duration and seed layer were such fundamental controlling parameters. The study brings out an outstanding piezoelectric coefficient (d(33)) of 44.33 pm/V for vertically aligned ZnO nanorod structures, considered as the highest reported d(33) value for any kind of ZnO nanostructures. XRD analysis confirms wurtzite nature of this nanorod structure with 0001] as preferential growth direction. Semiconducting characteristic of nanorods was determined with temperature induced I/V characterization.

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Translational regulation of the p53 mRNA can determine the ratio between p53 and its N-terminal truncated isoforms and therefore has a significant role in determining p53-regulated signaling pathways. Although its importance in cell fate decisions has been demonstrated repeatedly, little is known about the regulatory mechanisms that determine this ratio. Two internal ribosome entry sites (IRESs) residing within the 5'UTR and the coding sequence of p53 mRNA drive the translation of full-length p53 and Delta 40p53 isoform, respectively. Here, we report that DAP5, a translation initiation factor shown to positively regulate the translation of various IRES containing mRNAs, promotes IRES-driven translation of p53 mRNA. Upon DAP5 depletion, p53 and Delta 40p53 protein levels were decreased, with a greater effect on the N-terminal truncated isoform. Functional analysis using bicistronic vectors driving the expression of a reporter gene from each of these two IRESs indicated that DAP5 preferentially promotes translation from the second IRES residing in the coding sequence. Furthermore, p53 mRNA expressed from a plasmid carrying this second IRES was selectively shifted to lighter polysomes upon DAP5 knockdown. Consequently, Delta 40p53 protein levels and the subsequent transcriptional activation of the 14-3-3 sigma gene, a known target of Delta 40p53, were strongly reduced. In addition, we show here that DAP5 interacts with p53 IRES elements in in vitro and in vivo binding studies, proving for the first time that DAP5 directly binds a target mRNA. Thus, through its ability to regulate IRES-dependent translation of the p53 mRNA, DAP5 may control the ratio between different p53 isoforms encoded by a single mRNA.

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Contenido: Elementos para una definición del Derecho Internacional Privado / Raúl Alberto Ramayo – Elementos para determinar la jurisdicción ius privatista internacional / Raúl Alberto Ramayo – Mediación : elabore y decida su propia solución / Zulema Wilde – Contratos informáticos en la Argentina / Pablo Andrés Palazzi – El honor y la censura : ¿una contradicción? / Flavio F. Agatiello Piñero – La filosofía del derecho de Hegel y el catolicismo / Ignacio Andereggen – El arte político de los cristianos para la construcción de la ciudad del hombre / Franco Biffi – Servio Tulio, rey censor / Alfredo Grieco y Bavio – Una cuestión filosófica en el quinto centenario : ¿fue legítimo el imperio hispánico en América? / Héctor H. Hernández

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Analisa questões sobre a judicialização dos conflitos e o ativismo judicial, bem como aspectos referentes à Proposta de Emenda Constitucional (PEC 33/2011) que visa alterar dispositivos do texto magno a fim de aumentar ou criar o controle do Legislativo sobre algumas das decisões do Supremo Tribunal Federal.

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Report/South Africa- Recasting the Net, What’s New, Webby?- European Parliament resolution recognizes women in fisheries,America/Canada- Stuck at the back of the boat, Milestones- Magna Carta of Women adopted in Philippines, Profile- Chitra Suriyakumar: Living in Hope, Report/India- Women, the Eyes of the World, Q&A- Interview with Clarisse Canha from Associação para a Igualdade e Direitos das Mulheres —Association for Equality and Rights for Women (UMAR-Azores), Yemaya Mama- ... sums it up !! Yemaya Recommends- Fisherwomen, Fishermen’s Wives.

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The significance of the photoperiod, a well-known phenomenon with arthropods, for the development of Cyclops vicinus were studied in laboratory conditions. There are indications that the point of the development process (development of the eggs and proportion of sexes) can be influenced through the photoperiod.

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介绍了一种基于3×3和2×2光纤耦合器构成的非平衡马赫-曾德尔干涉仪的波长解调方案。理论分析和数据对比表明,相对于由两个2×2光纤耦合器构成的马赫-曾德尔干涉仪,本干涉仪具有宽谱的灵敏度、能跟踪波长的变化方向和相位展开的优点,实验方案用于测量固定在悬臂梁上的传感光纤布拉格光栅(FBG)的峰值波长变化,获得了±1pm的静态波长解调精度,在10Hz处的动态分辨率为27nε/√Hz。相位展开算法使得应变测量范围达到了2014με,对应的相位变化为3.22π。

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Investigations of the rearrangement of material in Neuwerk/Scharhom flat showed that with the exception of the western border/edge and the parts of the Elbe and Oste shores/banks which lie most seawards, the entire mudflat area is only infrequently exposed to strong hydraulic forces. Only in extreme conditions, which on average occur rarely more than once a year, would the mudflats be severely affected. This partial translation provides the summary of the original article only.

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This partial translation of a bigger publication provides an identification key to the aquatic plant Hydrillae (Hydrocharitaceae) in Europe. Illustrations are included.

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To ascertain the effect of various concentrations of oxygen in water on the fry of rainbow trout experiments were made with aquaria at various concentrations of oxygen. The food supplied was chironomid larvae (Chironomus plumosus). A surplus of food was supplied to the fry. Indices are given of the reaction of the fry to different temperatures.