986 resultados para 31.15.Ar


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A associação inversa da ingestão de cálcio dietético com adiposidade corporal e pressão arterial está documentada em estudos epidemiológicos. Achados experimentais sugerem que este fenômeno pode ser mediado por alterações na concentração intracelular de cálcio ([Ca]i). Existem poucos estudos relacionando o cálcio dietético com a [Ca]i. O objetivo do presente estudo foi avaliar a relação da ingestão habitual de cálcio dietético com a [Ca]i, adiposidade corporal, perfil metabólico, biomarcadores inflamatórios, pressão arterial e função endotelial em mulheres. Para tanto, foi desenvolvido estudo transversal, com 76 mulheres na pré-menopausa submetidas à avaliação: dietética (questionário de frequência alimentar validado); da [Ca]i em eritrócitos (espectrometria de absorbância atômica); da gordura corporal (GC) total [índice de massa corporal (IMC) e % GC por bioimpedância elétrica] e central [perímetro da cintura (PC), e razão cintura quadril (RCQ)]; do perfil metabólico (glicose, colesterol e frações, insulina e HOMA-IR); dos biomarcadores inflamatórios [adiponectina e proteína C-reativa (PCR)]; dos biomarcadores da função endotelial [molécula de adesão intracelular-1 (ICAM-1), molécula de adesão celular vascular-1 (VCAM-1) e E-Selectina]; da função endotelial avaliada pelo equipamento Endo-PAT2000; e da pressão arterial. Calcitriol, paratormônio, cálcio sérico e cálcio urinário completaram o metabolismo do cálcio. As participantes foram estratificadas em 2 grupos de acordo com a ingestão habitual de cálcio: Grupo com baixa ingestão de cálcio ou BIC (n=32; ingestão de cálcio <600mg/d) e Grupo com elevada ingestão de cálcio ou AIC (n=44; ingestão de cálcio ≥600mg/d). A média da idade foi semelhante entre os grupos (Grupo BIC: 31,41,4 vs Grupo AIC: 31,41,4anos; p=0,99). Após ajustes para fatores de confundimento (idade, ingestão de energia, bebida alcoólica, proteína, carboidratos e lipídios), o Grupo AIC, em comparação com o BIC, apresentou valores significativamente mais baixos de IMC (25,65,3 vs 26,9 6,0 kg/m; p=0,02), PC (84,413,6 vs 87,815,3cm; p=0,04), % GC (31,15,9 vs 33,35,6 %; p=0,003), pressão arterial diastólica (68,210,8 vs 72,411,2 mm Hg; p=0,04) e pressão arterial média (80,1310,94 vs 83,8611,70 mmHg; p=0,04); e significativamente mais altos de HDL-colesterol (58,612,2 vs 52,912,2 mg/dL; p=0,004) e adiponectina (34572,1 19472,8 vs 31910,319385,1 ng/mL; p=0,05). A [Ca]i e as outras variáveis avaliadas não diferiram entre os grupos, mesmo após ajustes. Neste estudo realizado com mulheres, o maior consumo de cálcio se associou com valores mais baixos de adiposidade corporal total e central, pressão arterial diastólica e média; além de valores mais elevados de HDL-colesterol e adiponectina

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This study is one of the very few investigating the dioxin body burden of a group of child-bearing-aged women at an electronic waste (e-waste) recycling site (Taizhou, Zhejiang Province) (24 +/- 2.83 years of age, 40% were primiparae) and a reference site (Lin'an city, Zhejiang Province, about 245 km away from Taizhou) (24 +/- 2.35 years of age, 100% were primiparae) in China. Five sets of samples (each set consisted of human milk, placenta, and hair) were collected from each site. Body burdens of people from the e-waste processing site (human milk, 21.02 +/- 13.81 pg WHO-TEQ(1998/g) fat (World Health Organization toxic equivalency 1998); placenta, 31.15 +/- 15.67 pg WHO-TEQ(1998/g) fat; hair, 33.82 +/- 17.74 pg WHO-TEQ(1998/g) dry wt) showed significantly higher levels of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurnas (PCDD/Fs) than those from the reference site (human milk, 9.35 +/- 7.39 pg WHO-TEQ(1998/g) fat, placenta, 11.91 +/- 7.05 pg WHO-TEQ(1998/g) fat; hair, 5.59 +/- 4.36 pg WHO-TEQ(1998/g) dry wt) and were comparatively higher than other studies. The difference between the two sites was due to e-waste recycling operations, for example, open burning, which led to high background levels. Moreover, mothers from the e-waste recycling site consumed more foods of animal origin. The estimated daily intake of PCDD/Fs within 6 months by breast-fed infants from the e-waste processing site was 2 times higher than that from the reference site. Both values exceeded the WHO tolerable daily intake for adults by at least 25 and 11 times, respectively. Our results implicated that e-waste recycling operations cause prominent PCDD/F levels in the environment and in humans. The elevated body burden may have health implications for the next generation.

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研究了黄土丘陵区油松天然次生林林窗的形状、大小结构、分布、形成木特征及其更新状况.结果表明:在油松天然次生林中,林冠林窗(CG)和扩展林窗(EG)面积均呈以小林窗为主的偏态分布.CG平均面积为31.15 m2,以20~40 m2林窗的数量比和面积比最大,分别为38.24%和30.50%;EG平均面积为58.04 m2,以30~60 m2的数量比和面积比最大,分别为36.77%和27.79%,且CG的平均面积占EG平均面积的53.67%;林窗形状多呈椭圆形,高度多在14~16 m;林窗形成年龄以10~20年为主,占33.82%.林窗中基折和枯立木分别占形成木总数的47.66%和23.44%.林窗形成的主要因素是人为间伐或盗伐,树木衰老等引起的抗性下降、干旱、病虫害等也是导致树木死亡的原因之一;每个林窗中平均有1.89个形成木,其中以2株形成木的林窗最多.林窗形成木主要是油松,其次为山杨、白桦和辽东栎等.形成木的径级呈明显的偏态分布,以10~20 cm和21~30 cm径级最为普遍,分别占总数的25.0%和45.31%,与林窗面积偏态分布吻合;林窗内林木的更新状况好于林下,且油松幼苗不存在断层,而油松林下幼苗在年...

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在中国原子能科学研究院的HI-13串列静电加速器上完成了19F+27Al耗散反应产物的激发函数测量。束流19F的入射能量从110.25MeV到118.75MeV,步长250keV,测量了实验室系+57°,+31°,-15°和-29°出射的类弹产物B,C,N,O,F和Ne的激发函数。观测到激发函数具有耗散反应的特征涨落结构,分析了激发函数之间的长程角度关联以及强烈的电荷数关联。

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采用符合关联实验技术进行的Ar~(q+)+Ne(q=8,9,11,12)碰撞体系中多电子转移过程的研究。在实验上鉴别了反应中各种电子转移过程,并测量了转移电离截面。研究了转移电离截面与反冲离子电荷态的关系,并利用修正后的分子过垒模型计算结果与实验结果进行了对比分析,计算结果较合理地描述了实验现象。

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本文在室内人工控制条件下,用切枝培养的方法研究了环境因子对龙须菜生长的影响。环境因子包括:海水温度、光照强度、硝酸盐浓度、磷酸盐浓度、盐度和维生素B_(12)。生长指标用切枝的长度增长和鲜重增加表示。首行以单因子实验找出该因子影响切枝生长的适宜范围,最后运用正交表L25(5~6),采用正交设计法进行多因子实验,选择的变化因子和其级别是根据单因子实验来定。实验结果表明:在本实验条件下,龙须菜切枝生长的最适条件是,温度20 ℃,光照强度8750Lux,NO3-N10mM, PO4-Po.1mM, 盐度31%。切枝生长的适宜条件是,温度15-25 ℃,光照强度是3900-9500Lux, NO3-N 1-10mM.PO4-P0.01-0.1mM,盐度20-45%,VB_(12)对切枝长生的影响不显著。本实验的研究方法和结果对大型海藻的人工栽培工作有一定的参考价值。

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根据岩石矿物学研究,包括岩石结构、橄榄石的Fa值和低钙辉石的Fs值以及金属模式含量等,100块格罗夫山陨石分别被划分为:4块H3型、11块H4型(其中一块为H4-an)、10块H5型、3块H6型、2块L3型、6块L4型、31块15型、32块L6型和1块LL4型。格罗夫山普通球粒陨石在类型分布上,其比例和南极以及非南极普通球粒陨石有显著不同,说明可能存在相当数量的成对陨石。分类陨石样品比较新鲜,其中98块陨石的风化程度为W1,仅有2块陨石风化程度分别为W2和W3。另外,这些陨石中冲击程度较高的样品占有一定比例,它们是研究冲击作用的理想样品。

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Due to their high risk of developing severe Bordetella pertussis (Bp) infections, it is recommended to immunize preterm infants at their chronological age. However, little is known about the persistence of their specific immune responses, especially of the cellular responses recognized to play a role in protection. We compared here the cellular immune responses to two major antigens of Bp between three groups of one year-old children born prematurely, who received for their primary vaccination respectively the whole cell vaccine Tetracoq(®) (TC), the acellular vaccine Tetravac(®) (TV), or the acellular vaccine Infanrix-hexa(®) (IR). Whereas most children had still detectable IFN-γ responses at one year of age, they were lower in the IR-vaccinated children compared to the two other groups. In contrast, both the TV- and the IR-vaccinated children displayed higher Th2-type immune responses, resulting in higher antigen-specific IFN-γ/IL-5 ratios in TC- than in TV- or IR-vaccinated children. The IFN-γ/IL-5 ratio of mitogen-induced cytokines was also lower in IR- compared to TC- or TV-vaccinated children. No major differences in the immune responses were noted after the booster compared to the pre-booster responses for each vaccine. The IR-vaccinated children had a persistently low specific Th1-type immune response associated with high specific Th2-type immune responses, resulting in lower antigen-specific IFN-γ/IL-5 ratios compared to the two other groups. We conclude that antigen-specific cellular immune responses persisted in one year-old children born prematurely and vaccinated during infancy at their chronological age, that a booster dose did not significantly boost the cellular immune responses, and that the Th1/Th2 balance of the immune responses is modulated by the different vaccines.

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Displacement of fossil fuel-based power through biomass co-firing could reduce the greenhouse gas (GHG) emissions from fossil fuels. In this study, data-intensive techno-economic models were developed to evaluate different co-firing technologies as well as the configurations of these technologies. The models were developed to study 60 different scenarios involving various biomass feedstocks (wood chips, wheat straw, and forest residues) co-fired either with coal in a 500 MW subcritical pulverized coal (PC) plant or with natural gas in a 500 MW natural gas combined cycle (NGCC) plant to determine their technical potential and costs, as well as to determine environmental benefits. The results obtained reveal that the fully paid-off coal-fired power plant co-fired with forest residues is the most attractive option, having levelized costs of electricity (LCOE) of $53.12–$54.50/MW h and CO2 abatement costs of $27.41–$31.15/tCO2. When whole forest chips are co-fired with coal in a fully paid-off plant, the LCOE and CO2 abatement costs range from $54.68 to $56.41/MW h and $35.60 to $41.78/tCO2, respectively. The LCOE and CO2 abatement costs for straw range from $54.62 to $57.35/MW h and $35.07 to $38.48/tCO2, respectively.

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Im Rahmen der Dichtefunktionaltheorie wurden Orbitalfunktionale wie z.B. B3LYP entwickelt. Diese lassen sich mit der „optimized effective potential“ – Methode selbstkonsistent auswerten. Während sie früher nur im 1D-Fall genau berechnet werden konnte, entwickelten Kümmel und Perdew eine Methode, bei der das OEP-Problem unter Verwendung einer Differentialgleichung selbstkonsistent gelöst werden kann. In dieser Arbeit wird ein Finite-Elemente-Mehrgitter-Verfahren verwendet, um die entstehenden Gleichungen zu lösen und damit Energien, Dichten und Ionisationsenergien für Atome und zweiatomige Moleküle zu berechnen. Als Orbitalfunktional wird dabei der „exakte Austausch“ verwendet; das Programm ist aber leicht auf jedes beliebige Funktional erweiterbar. Für das Be-Atom ließ sich mit 8.Ordnung –FEM die Gesamtenergien etwa um 2 Größenordnungen genauer berechnen als der Finite-Differenzen-Code von Makmal et al. Für die Eigenwerte und die Eigenschaften der Atome N und Ne wurde die Genauigkeit anderer numerischer Methoden erreicht. Die Rechenzeit wuchs erwartungsgemäß linear mit der Punktzahl. Trotz recht langsamer scf-Konvergenz wurden für das Molekül LiH Genauigkeiten wie bei FD und bei HF um 2-3 Größenordnungen bessere als mit Basismethoden erzielt. Damit zeigt sich, dass auf diese Weise benchmark-Rechnungen durchgeführt werden können. Diese dürften wegen der schnellen Konvergenz über der Punktzahl und dem geringen Zeitaufwand auch auf schwerere Systeme ausweitbar sein.

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Comunicación en la que se presenta una aportación al estudio de la toponimia en la zona fronteriza con Portugal, en concreto la toponimia de los actuales municipios de Olivenza y Táliga. El trabajo forma parte de un estudio más amplio cuyo objetivo principal era analizar la toponimia de esta zona que perteneció durante siglos a Portugal.

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This study presents a systematic and quantitative analysis of the effect of inhomogeneous surface albedo on shortwave cloud absorption estimates. We used 3D radiative transfer modeling over a checkerboard surface albedo to calculate cloud absorption. We have found that accounting for surface heterogeneity enhances cloud absorption. However, the enhancement is not sufficient to explain the reported difference between measured and modeled cloud absorption.

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Activities involving fauna monitoring are usually limited by the lack of resources; therefore, the choice of a proper and efficient methodology is fundamental to maximize the cost-benefit ratio. Both direct and indirect methods can be used to survey mammals, but the latter are preferred due to the difficulty to come in sight of and/or to capture the individuals, besides being cheaper. We compared the performance of two methods to survey medium and large-sized mammal: track plot recording and camera trapping, and their costs were assessed. At Jatai Ecological Station (S21 degrees 31`15 ``- W47 degrees 34`42 ``-Brazil) we installed ten camera traps along a dirt road directly in front of ten track plots, and monitored them for 10 days. We cleaned the plots, adjusted the cameras, and noted down the recorded species daily. Records taken by both methods showed they sample the local richness in different ways (Wilcoxon, T=231; p;;0.01). The track plot method performed better on registering individuals whereas camera trapping provided records which permitted more accurate species identification. The type of infra-red sensor camera used showed a strong bias towards individual body mass (R(2)=0.70; p=0.017), and the variable expenses of this method in a 10-day survey were estimated about 2.04 times higher compared to track plot method; however, in a long run camera trapping becomes cheaper than track plot recording. Concluding, track plot recording is good enough for quick surveys under a limited budget, and camera trapping is best for precise species identification and the investigation of species details, performing better for large animals. When used together, these methods can be complementary.