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关键词： 三线摆   转动周期   转动惯量   重力加速度  

摘要： 通过三线摆法测量三线摆下圆盘转动惯量原理,推导出利用三线摆法测量重力加速度表达式。为了提高三线摆法测量哈尔滨地区重力加速度的准确性,设定转动周期个数分别为5、10、20、30、40和50个。研究设定不同转动周期个数,空气阻力及悬线间摩擦对三线摆法所测重力加速度准确度的影响。发现设置测量周期个数为40个时,所测得的重力加速度最接近哈尔滨地区实际重力加速度值。

关键词： 增量动力分析   双向地震动   偏心结构   能力曲线  

摘要： 以往的增量动力分析(Incremental Dynamic Analysis,IDA)研究主要是针对单向地震下的对称结构,而对于地震动的多维性、结构偏心引起的扭转效应的影响则考虑较少。为此,设计了一幢5层的偏心结构模型,选取Taft双向地震记录为双向激励对结构模型进行多维增量动力分析。分析了结构在地震下的扭转效应对边缘框架反应的放大作用,并基于IDA能力曲线对结构模型进行多性能水准抗震评估。通过算例分析得到以下结论:基于IDA的结构抗震评估方法,概念清晰,操作简单;偏心结构在双向地震下的扭转效应会导致部分边缘框架的反应放大,且地震强度越大这种放大效应越明显;当考虑双向地震作用时,直接采用建议的双向IDA方法进行结构性能分析更具合理性。

关键词： 高山林线   高度   地形   贺兰山  

摘要： 运用遥感数据和空间分析技术提取贺兰山高山林线,并结合DEM数据计算相关地形因子,采用相关分析和多元回归分析定量研究不同地形因子对高山林线分布高度的影响.结果表明,贺兰山高山林线上、下边界平均高度分别为3 106和3 022m,主山脊西侧山地高山林线上、下边界分布高度范围和平均高度比东侧略高.在山地两侧影响高山林线上边界高度的地形因子及其贡献率具有差异.南北朝向指数和地形指数对山地西侧高山林线上边界高度变化的相对贡献率分别为56.7%和43.3%;南北朝向指数、地形指数和坡度对东侧高山林线上边界高度变化的相对贡献率分别为50.9%、31.0%和18.1%.坡向是影响贺兰山高山林线分布高度的重要地形因素,而坡面凹凸程度和坡度对高山林线分布高度的影响与其他地形因素具有一定关系.

关键词： 桥梁   影响线   损伤定位   箱梁   跨中挠度  

摘要： 为了实现箱梁桥的损伤定位,利用梁式桥结构损伤必然影响弯曲刚度,则梁体跨中挠度影响线将不再以跨中为轴对称分布这一特点,提出了以桥梁损伤前后跨中挠度影响线三次差值为指标的损伤定位方法。对一座简支箱梁桥按照单一部位损伤和多部位同时损伤予以分析计算,在预设损伤部位均出现了损伤指标的明显突变,表明该方法对箱梁的单部位和多部位损伤定位具有较好的适用性。

摘要： 914P

关键词： 核工业水池   反应位移法   抗震设计   地基弹簧系数   SL1   SL2  

摘要： 介绍了反应位移法的基本原理和计算方法,并在大型有限元商业软件ANSYS中实现,将其应用于核电厂工业水池抗震设计分析,对不同工况下的工业水池的内力分布展开研究,同时通过ANSYS的二次开发并结合五点公式计算得到结构内力分布规律及其危险工况,为工业水池合理截面设计及配筋方案提供技术支持。结果表明:工业水池侧墙最大弯矩发生在中间部位的中部和底部,在同等抗震等级条件下,SL1地震作用下侧墙弯矩大于SL2地震作用下的;柱子内力规律性明显,水池中间所受内力最大,SL2地震作用下变形结果大于SL1地震作用下的,空水状态为危险工况,且采用适当的配筋措施能够满足结构抗震要求。该研究成果可为核电工业水池抗震设计或其他类似工程的设计提供参考。

关键词： 铜银合金   导电性能   抗拉强度   银含量   线坯   力学性能   连铸连轧   影响规律  

摘要： 研究了连铸连轧铜银合金接触线的力学性能和导电性能，分析了银含量对铜银合金接触线坯抗拉强度和导电性能的影响规律，并优化得到较优的银含量。试验结果表明：添加银后，铜合金的抗拉强度增加，电阻率增加。

关键词： androgen receptor   cell viability   LNCaP cells   red Maca  

摘要： We examined whether aqueous extract of Lepidium meyenii (red Maca) could inhibit growth, potentiate apoptotic activity of two anticancer drugs Taxol and 2-methoxyestradiol (2ME) or change mRNA expression for the androgen target genes, androgen receptor (Ar) and prostate-specific antigen (Psa) in the human prostate cancer cell line LNCaP. Red Maca aqueous extract at 0, 10, 20, 40 or 80 mu g/ml was added to LNCaP cells, and viability was evaluated by the MTS assay at 24 or 48 hr after treatment. Furthermore, LNCaP cells were treated with 80 mu g/ml of red Maca plus Taxol or 2ME 5 mu M and viability was assessed 48 hr later. Finally, LNCaP cells were treated with red Maca 0, 20, 40 or 80 mu g/ml, and 12 hr later, mRNA level for Ar or Psa was assessed by real-time PCR. Treatment with red Maca did not affect viability of LNCaP cells. Apoptotic activity induced by Taxol and 2ME in LNCaP cells was not altered with red Maca treatment. Relative expression of the mRNA for Ar and Psa increased with red Maca 20 and 40 mu g/ml, but not at 80 mu g/ml. We conclude that red Maca aqueous extract does not have toxic effects, but stimulates androgen signalling in LNCaP cells.

关键词： Glioma   lncRNA   MALAT1   ERK/MAPK  

摘要： Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is among the most abundant and highly conserved lncRNAs, which has been detected in a wide variety of human tumors, including gastric cancer, gallbladder cancer, and so on. Previous research has showed that MALAT1 can activate LTBP3 gene in mesenchymal stem cells. However, the specific roles of MALAT1 in glioma stem cells (GSCs) remain unclear. In this study, we aimed to identify the effects of MALAT1 on proliferation and the expression of stemness markers on glioma stem cell line SHG139S. Our results showed that downregulation of MALAT1 suppressed the expression of Sox2 and Nestin which are related to stemness, while downregulation of MALAT1 promoted the proliferation in SHG139S. Further research on the underlying mechanism showed that the effects of MALAT1 downregulation on SHG139S were through regulating ERK/MAPk signaling activity. And we also found that downregulation of MALAT1 could activate ERK/MAPK signaling and promoted proliferation in SHG139 cells. These findings show that MALAT1 plays an important role in regulating the expression of stemness markers and proliferation of SHG139S, and provide a new research direction to target the progression of GSCs.

关键词： Deepwater Horizon   Oil spill   Environmental toxicology   Swim performance   Fish indices  

摘要： The temporal and geographic attributes of the Deepwater Horizon incident in 2010 likely exposed pelagic game fish species, such as mahi-mahi, to crude oil. Although much of the research assessing the effects of the spill has focused on early life stages of fish, studies examining whole-animal physiological responses of adult marine fish species are lacking. Using swim chamber respirometry, the present study demonstrates that acute exposure to a sublethal concentration of the water accommodated fraction of Deepwater Horizon crude oil results in significant swim performance impacts on young adult mahi-mahi, representing the first report of acute sublethal toxicity on adult pelagic fish in the Gulf of Mexico following the spill. At an exposure concentration of 8.4 +/- 0.6 mu gL(-1) sum of 50 selected polycyclic aromatic hydrocarbons (PAHs;mean of geometric means +/- standard error of the mean), significant decreases in the critical and optimal swimming speeds of 14% and 10%, respectively (p<0.05), were observed. In addition, a 20% reduction in the maximum metabolic rate and a 29% reduction in aerobic scope resulted from exposure to this level of sigma PAHs. Using environmentally relevant crude oil exposure concentrations and a commercially and ecologically valuable Gulf of Mexico fish species, the present results provide insight into the effects of the Deepwater Horizon oil spill on adult pelagic fish. Environ Toxicol Chem 2016;35:2613-2622. (c) 2016 SETAC