139 resultados para 4101
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CONTEXT AND OBJECTIVE: Suboptimal vitamin D status can be corrected by vitamin D supplementation, but individual responses to supplementation vary. We aimed to examine genetic and nongenetic determinants of change in serum 25-hydroxyvitamin D (25(OH)D) after supplementation. DESIGN AND PARTICIPANTS: We used data from a pilot randomized controlled trial in which 644 adults aged 60 to 84 years were randomly assigned to monthly doses of placebo, 30 000 IU, or 60 000 IU vitamin D3 for 12 months. Baseline characteristics were obtained from a self-administered questionnaire. Eighty-eight single-nucleotide polymorphisms (SNPs) in 41 candidate genes were genotyped using Sequenom MassArray technology. Serum 25(OH)D levels before and after the intervention were measured using the Diasorin Liaison platform immunoassay. We used linear regression models to examine associations between genetic and nongenetic factors and change in serum 25(OH)D levels. RESULTS: Supplement dose and baseline 25(OH)D level explained 24% of the variability in response to supplementation. Body mass index, self-reported health status, and ambient UV radiation made a small additional contribution. SNPs in CYP2R1, IRF4, MC1R, CYP27B1, VDR, TYRP1, MCM6, and HERC2 were associated with change in 25(OH)D level, although only CYP2R1 was significant after adjustment for multiple testing. Models including SNPs explained a similar proportion of variability in response to supplementation as models that included personal and environmental factors. CONCLUSION: Stepwise regression analyses suggest that genetic variability may be associated with response to supplementation, perhaps suggesting that some people might need higher doses to reach optimal 25(OH)D levels or that there is variability in the physiologically normal level of 25(OH)D.
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The piezoelectric composite material could engender stress concentration resulting from small cracks during layers easily, as the cracks growth will lead to the failure of the whole structure. In this paper, a finite element model for piezoelectric composite materials by ABAQUS including interlayer crack was established, and the J integral and crack tip stress of different types PZT patches were calculated by using the equivalent integral method. Then, the J integral for adhesive layers with different thickness, elastic modulus considering and not considering piezoelectricity was investigated. The results show that the J integral of mode I, II reduces with thicker adhesive layer and lower elastic modules, and the J integral of mode II decreases more sharply than that of mode I.
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In 2006, Tobacco streak virus (TSV) was identified as the causal agent of the devastating sunflower necrosis disease in central Queensland (CQ), and subsequently in 2007 as the cause of major losses in mungbeans in the same area. It has been a major factor in the recent downturn in the sunflower industry in CQ. Surveys in 2007/2008 as part of a one year scoping study (project 03DAQ005) found TSV in cotton in CQ. The symptoms were mostly confined to the feeding sites of the thrips and appeared as reddish spots and rings, but only occasionally the plants were systemically infected and showed a chlorotic mosaic and leaf deformation. The major objectives of this project (DAQ0002) were to determine: the incidence and distribution of TSV in cotton and its likely effect on yield; the thrips vector species associated with TSV infections in cotton; and the factors that may lead to systemic infections. In contrast to the extensive damage observed in sunflower and mungbean crops from the same region, TSV has caused no measurable damage in commercial cotton crops surveyed in CQ over the seasons 2008/9 to 2010/11. No TSV infected cotton was found in regions outside of CQ and the geographical distribution of TSV disease in cotton (and other susceptible hosts) appears to be closely related to the distribution of the major alternative host, parthenium weed. The most likely thrips species responsible for transmission of TSV into cotton is the tomato thrips (Frankliniella schultzei) and onion thrips (Thrips tabaci). Systemically infected plants are rarely seen in commercial crops and have also been rarely produced in controlled tests. It appears that systemic infection may be transient with only mild symptoms being produced intermittently. With current cultivars and conditions, it appears likely that TSV will continue to cause only minor levels of mild local lesions with no impact on yield in cotton crops. It appears that no specific control strategies are required to limit the impact of TSV in cotton. However, general farm hygiene to minimise the presence of the major alternative host of TSV, parthenium weed, is advised and may be of vital importance if TSV susceptible rotational crops such as mung beans are grown.
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本文提供了电流测量线圈的误差公式。用电流测量线圈测量了TEA脉冲CO_2激光器的放电电流。
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Hematological effects of feeding varying dietary crude proteins levels to one hundred and fifty (150) H.longifilis fingerlings was examined on biweekly basis. The fingerlings of mean weights 1.26g plus or minus 0.24g were stocked in eight hapa nets (1mx1m) at 15 fingerlings per hapa. Four experimental diets with crude protein; 35%, 40%, 45% and 50% coded diet 1-4 respectively were fed to the fish for 8 weeks. The blood sample was taken and examined for packed cell volume (PCV) total protein (TP) Hemoglobin (Hb), Serum album, Erythrocyte count (RBC), while blood cell (WBC) mean corpuscle volume (MCV) and mean corpuscle hemoglobin, concentration (MCHC). There was an increase in the values of the hematological indices studied with increase in protein inclusion levels. A higher positive correlation with no significant difference (P greater than or equal to 0.05) exists between the treatments RBC, WBC, Hb and TP. The best RBC (2.10x10 super(6) count/l). WBC (7.65x10 super(4) count/l), PCV (35.4%) and Hb (5.79mg/l) were presented in fingerlings fed 40% crude protein followed by 45% crude protein. The dietary crude protein of 40% is recommended for H. longifilis for sound and healthy condition
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A dissertação tem por objeto a análise das novas formas de tratamento processual dos direitos individuais homogêneos, os quais frequentemente dão ensejo à propositura de ações repetitivas, especialmente a partir da tendência pela adoção de procedimentos de agregação de ações em alguns países. Assim, analisam-se as ações-teste estabelecidas pela Alemanha (Musterverfahren), Inglaterra (Group Litigation Order) e o incidente de resolução de demandas repetitivas previsto no Projeto de novo Código de Processo Civil brasileiro (PL 8.046/2010). Como esta espécie de direitos também pode ser tutelada por ações coletivas, o trabalho contém um estudo sobre suas principais características, como a representatividade adequada e os diferentes sistemas de extensão dos efeitos produzidos pela coisa julgada formada nestas ações. Todo este debate é precedido da análise dos princípios constitucionais da isonomia e da segurança jurídica, do movimento mundial de aproximação entre os sistemas de civil law e common law, e da crescente tendência uniformizadora da jurisprudência brasileira.
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Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-06-04T08:36:34Z No. of bitstreams: 1 dspace.cfg: 33388 bytes, checksum: ac9630d3fdb36a155287a049e8b34eb7 (MD5)
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提出了一种微光机电系统(MoEMS)可调谐滤波器结构,该结构采用GaAs/AlGaAs作为下分布布拉格反射镜(DBR),GaAs和SiO_2/Si介质膜作为上DBR,空气作为腔.按照波分复用系统的性能要求对MOEMS可调谐滤波器各项参数,如带宽、峰值透射率、挠度和调谐速度等进行了分析和设计.研究了挠度和调谐速度与梁厚度、宽度、长度等参数的关系.结果表明挠度与长度成正方向变化,同梁厚度、宽度成反方向变化,而调谐速度与各参数的关系恰好相反.
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利用Skyrme有效相互作用 ,采用核子 -核子相互作用参数SKM 和SⅢ对自旋极化的同位旋非对称核物质的特性和状态方程进行了研究 ,讨论了非对称核物质的磁化率随密度的变化关系及其同位旋依赖性 .结果表明 :在Skyrme Hartree Fock框架内 ,同位旋非对称核物质会发生从非极化态到极化态的相变 ,而且发生相变的临界密度随同位旋非对称度增大而降低 .另外 ,还与微观BHF (Brueckner Hartree Fock)的理论预言进行了比较和讨论