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181.
182.
2016年,OPEC的产量决策将对全球石油供应形势产生重要的影响,也将影响市场对于油价重回上升通道的信心和预期。全球经济形势,特别是OECD国家的复苏进度将成为影响需求增长的关键因素。美元汇率走势、市场投机活动以及地缘政治事件都将成为油价短期波动的不确定因素。文章通过自主研发的油价综合分析预测系统预测,2016年国际油价将继续保持低位震荡,Brent年平均油价为53美元/桶,WTI年平均油价为49美元/桶,平均价差为4美元/桶。影响这一趋势的最大不确定性是OPEC的政策以及OPEC与俄罗斯等产油国之间的博弈。 相似文献
183.
针对基层维修人员复杂的故障难以诊断的问题,以PXI总线仪器为基础,提出了一种便携式维修辅助设备的设计方案。综合集成虚拟仪器、计算机、交互式电子技术手册、数据库、网络等技术,设计了便携式维修辅助设备的硬件结构,构建由装备基础信息数据库、BIT数据交互与分析软件、测试程序开发和执行软件、故障诊断与定位软件等组成的软件系统。介绍了设备的工作模型,利用便携式维修辅助设备,现场人员可迅速、准确地检测武器装备存在的故障隐患,隔离到现场可更换单元,满足现代战争对复杂武器系统原位检测和故障诊断的需要。 相似文献
184.
185.
Jeong Ah Kim Hong Nam Kim Sun-Kyoung Im Seok Chung Ji Yoon Kang Nakwon Choi 《Biomicrofluidics》2015,9(2)
We present an engineered three-dimensional (3D) in vitro brain microvasculature system embedded within the bulk of a collagen matrix. To create a hydrogel template for the functional brain microvascular structure, we fabricated an array of microchannels made of collagen I using microneedles and a 3D printed frame. By culturing mouse brain endothelial cells (bEnd.3) on the luminal surface of cylindrical collagen microchannels, we reconstructed an array of brain microvasculature in vitro with circular cross-sections. We characterized the barrier function of our brain microvasculature by measuring transendothelial permeability of 40 kDa fluorescein isothiocyanate-dextran (Stoke''s radius of ∼4.5 nm), based on an analytical model. The transendothelial permeability decreased significantly over 3 weeks of culture. We also present the disruption of the barrier function with a hyperosmotic mannitol as well as a subsequent recovery over 4 days. Our brain microvasculature model in vitro, consisting of system-in-hydrogel combined with the widely emerging 3D printing technique, can serve as a useful tool not only for fundamental studies associated with blood-brain barrier in physiological and pathological settings but also for pharmaceutical applications. 相似文献
186.
将中西文化结合,阐述大众文化对大学生的影响;剑与诗词同生共长的历史渊源;Cosplay与剑术结合对武术发展的意义;与Cosplay结合对诗词发展的意义;对大学生的人文素质发展的意义。 相似文献
187.
陈激 《中国现代教育装备》2015,(3):117-120
通过阐述建设符合高职英语课程要求及学生特点的数字化教学资源库的必要性,分析了该资源库的基本构想,并提出了依托数字化教学资源库、促进高职英语课程教学改革发展的思路。 相似文献
188.
马骥 《邵阳学院学报(社会科学版)》2015,(2):55-59
改革开放以来,中国政府一直致力于消除农村贫困的工作,并取得了巨大的成就。中国农村反贫困演进可分为制度变革、针对性区域扶贫开发、扶贫攻坚、全面综合扶贫开发和精准扶贫开发五个阶段。文章对每个阶段的实施背景、政策特征与成效进行分析,并得到反贫困政策的启示。 相似文献
189.
Chun Pang Yu-chen Sheng Ping Jiang Hai Wei Li-li Ji 《Journal of Zhejiang University. Science. B》2015,16(7):602-610
Chlorogenic acid (CGA), a polyphenolic compound, is abundant in fruits, dietary vegetables, and some medicinal herbs. This study investigated the prevention of CGA against acetaminophen (AP)-induced hepatotoxicity and its engaged mechanisms. CGA reversed the decreased cell viability induced by AP in L-02 cells in vitro. In addition, CGA reduced the AP-induced increased serum levels of alanine/aspartate aminotransferase (ALT/AST) in vivo. The effect of CGA on cytochrome P450 (CYP) enzymatic (CYP2E1, CYP1A2, and CYP3A4) activities showed that CGA caused very little inhibition on CYP2E1 and CYP1A2 enzymatic activities, but not CYP3A4. The measurement of liver malondialdehyde (MDA), reactive oxygen species (ROS), and glutathione (GSH) levels showed that CGA prevented AP-induced liver oxidative stress injury. Further, CGA increased the AP-induced decreased mRNA expression of peroxiredoxin (Prx) 1, 2, 3, 5, 6, epoxide hydrolase (Ephx) 2, and polymerase (RNA) II (DNA directed) polypeptide K (Polr2k), and nuclear factor erythroid-2-related factor 2 (Nrf2). In summary, CGA ameliorates the AP-induced liver injury probably by slightly inhibiting CYP2E1 and CYP1A2 enzymatic properties. In addition, cellular important antioxidant signals such as Prx1, 2, 3, 5, 6, Ephx2, Polr2k, and Nrf2 also contributed to the protection of CGA against AP-induced oxidative stress injury. 相似文献
190.
Three cooking methods, namely boiling, steaming, and stir-frying for 5 to 10 min, were used to evaluate the effect on nutrient
components, free amino acids, l-ascorbic acid, total phenolic contents, and antioxidant capacities of bamboo shoots (Phyllostachys praecox). Results showed that boiling and stir-frying had a great effect on the nutrient components and they decreased the contents
of protein, soluble sugar, and ash, and caused a great loss in the total free amino acids (decreased by 38.35% and 34.86%,
respectively). Significant differences (P<0.05) in free amino acids were observed in the samples cooked by different methods. Stir-fried bamboo shoots had a high fat
content which increased by 528.57% because of the addition of edible oil. After boiling, the L-ascorbic acid and total phenolic
contents were significantly reduced, while steaming increased total phenolic content by 3.98% and stir-frying well-preserved
L-ascorbic acid (78.87% of its previous content). Results of the antioxidative property study showed that stir-frying could
increase antioxidant capacities of bamboo shoots. It is concluded that stir-frying is more suitable for bamboo shoots because
it could obtain the maximum retention of antioxidant capacities. 相似文献