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关键词： 小箱梁   荷载横向分布系数   弹性支承框架法   有限元   影响线  

摘要： 将小箱梁横截面取为框架模型,各片小箱梁纵向的抗弯和抗扭刚度等效成弹性支承,利用杆系有限元分析框架在单位移动荷载作用下各片小箱梁(对应为弹性支承)的横向影响线,得到小箱梁的荷载横向分布系数,并与修正的偏心压力法、刚接梁法及空间实体模型等方法的结果进行比较。得到的结果与修正偏心压力法极为接近,与刚接梁法的最大偏差也在5%以内,验证了该方法可行性和准确性。

关键词： 电磁感应现象   平均值法   位移   导体   巧解   磁感应强度   匀强磁场   导轨  

摘要： 例题如图1，质量为m的跨接杆可以无摩擦地沿水平的平行导轨滑行，两轨间宽度为L导轨与电阻R连接，放在竖直向上的匀强磁场中，磁感应强度为B，杆的初速为V0，杆和导轨的电阻不计．试求杆到停下来所滑行的距离．

关键词： 民间金融   杠杆   楼市暴涨  

摘要： 目前我国面临着巨额的房产库存,加上银行对住房抵押贷款的收紧,理论上说房价应该下降,但是近来我国一线城市房价却在暴涨,毫无疑问民间金融在楼市暴涨中发挥了重要的作用。为了分析民间金融对当前一线城市楼市暴涨的助推作用及负面影响,本文通过一线城市近年来房价及贷款来源等数据,利用经济学供求等理论进行分析,结果显示民间金融对当前一线城市楼市暴涨的助推作用主要是通过民间金融机构的杠杆资金进入楼市发挥的。通过本研究对民间金融的监管以及应对楼市暴涨提出了相关的政策性建议。

关键词： 同塔双回直流   共用接地极   单极金属回线   单极大地回线   分流  

摘要： 牛从直流为同塔双回共用接地极建设工程,一回单极金属与单极大地回线方式相互转换过程中存在接地极接入、站高速接地开关合上的短暂过程,若此时另一回为单极大地回线方式运行,则接地极电流将在转换回产生分流。分析单极大地运行回的接地极电流分流至另一回的机理,梳理该分流电流对保护的影响,并提出防范措施和建议。

关键词： 兵器科学与技术   行进间射击精度   乘坐舒适性   底盘线振动   坦克装甲车辆  

摘要： 针对某型坦克高速行进间射击精度较低的问题,从底盘线振动的角度分析了炮弹出膛的横向速度、瞄准系统成像质量、乘员观瞄操纵效能三方面的影响因素,并结合实车试验数据逐一研究了每个因素对射击精度的影响。研究结果表明:底盘线振动引起的横向射击偏差较小,不足以引起射击精度的大幅降低;底盘线振动虽然对瞄准镜成像质量虽然有一定的影响,但基本不会影响观瞄效果;而由于乘员乘坐位置线振动较大,乘员的乘坐舒适性较差,使其难以精确操纵瞄准设备,从而影响观瞄效果。因此,车辆底盘线振动对坦克装甲车辆射击精度的影响主要表现在对乘员乘坐舒适性的影响上,乘员舒适性较差是限制行进间射击精度的重要原因。

关键词： 地铁项目   房地产价值   天津市地铁  

摘要： 建立地铁系统已经成为解决交通拥堵和环境恶化等城市问题的有效措施,同时地铁项目的建设对城市环境有着显著的外部影响,其中首当其冲的是对地铁站点周边房地产价值的促进作用。天津市是我国北方最大的沿海开放城市,因其独特的背景,将其选为研究对象。运用Hedonic Pricing模型对天津市已建成的地铁3号线站点周边1000m范围内房地产价值变动进行分析,发现地铁线路对房地产价值的影响——非城市中心区大于城市中心区;最后提出地铁项目对城市的主城区与非主城区的影响不同,并根据这一特点采取不同的发展策略。

摘要： The Genea078 human embryonic stem cell line was derived from a donated, fully commercially consented ART blastocyst, carrying compound heterozygous mutations in the NEB gene, exon 55 deletion & c.15110dupA, indicative of Nemaline Myopathy Type 2 (NEM2). Following ICM outgrowth on inactivated human feeders, karyotype was confirmed as 46, XX and STR analysis demonstrated a female Allele pattern. The hESC line had pluripotent cell morphology, 76% of cells expressed Nanog, 93% Oct4, 67% Tra1-60 and 97% SSEA4 and gave a Pluritest Pluripotency score of 42.18, Novelty of 1.37. The cell linewas negative for Mycoplasma and visible contamination. c 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://***/licenses/by-nc-nd/4.0/).

摘要： The Genea020 human embryonic stem cell line was derived from a donated, fully commercially consented ART blastocyst, carrying Htt gene CAG expansion of 48 repeats, indicative of Huntington disease. Following ICM outgrowth on inactivated human feeders, karyotype was confirmed as 46, XX by CGH and STR analysis demonstrated a female allele pattern. The hESC line had pluripotent cell morphology, 89% of cells expressed Nanog, 95% Oct4, 29% Tra1-60 and 99% SSEA4, gave a Pluritest pluripotency score of 27.51, novelty of 1.43 and demonstrated alkaline phosphatase activity. The cell line was negative for Mycoplasma and visible contamination. (C) 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://***/licenses/by-nc-nd/4.0/).

关键词： Oil spills   Sea turtles  

摘要： Researchers investigating the effects of the Deepwater Horizon oil spill on sea turtles found that over 320,000 juvenile sea turtles from populations throughout the Atlantic Ocean were likely present in the northern Gulf of Mexico during the 87-day oil spill in 2010. The study, led by researchers at the University of Miami, has important implications for international management and restoration efforts following oil spills. "There is a perception that the spill's impacts were largely contained to the northern Gulf of Mexico, because that is where the oil remained," said the study's lead author, Nathan Putman. "However, this overlooks the movement of migratory and dispersive marine animals into the area from distant locations."

关键词： Apoptosis   fluoride   hepatocyte   lead   proliferation index   vitality  

摘要： Chronic long-term exposure to high levels of fluoride leads to fluorosis, manifested by skeletal fluorosis and damage to internal organs, including kidneys, liver, parathyroid glands, and brain. Excess fluoride can also cause DNA damage, trigger apoptosis, and change cell cycle. The effect of fluoride may be exacerbated by lead (Pb), a potent inhibitor of many enzymes and a factor causing apoptosis, still present in the environment in excessive amounts. Therefore, in this study, we investigated the effects of sodium fluoride (NaF) and/or lead acetate (PbAc) on development of apoptosis, cell vitality, and proliferation in the liver cell line HepG2. We examined hepatocytes from the liver cell line HepG2, incubated for 48 h with NaF, PbAc, and their mixture (NaF + PbAc), and used for measuring apoptosis, index of proliferation, and vitality of cells. Incubation of the hepatocytes with NaF or PbAc increased apoptosis, more when fluoride and Pb were used simultaneously. Vitality of the cells depended on the compound used and its concentration. Proliferation slightly increased and then decreased in a high fluoride environment;it decreased significantly after addition of Pb in a dose-dependent manner. When used together, fluoride inhibited the decreasing effect of Pb on cell proliferation.