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关键词： 空间网格结构   几何非线性动力分析   主振型   切线刚度分离法   非线性模态法  

摘要： 空间网格结构因自由度数多且无简化的力学模型,非线性动力分析通常要耗费大量时间.传统的非线性模态方法用于求解多高层结构的局部非线性问题已获得良好的效果,但对系统非线性问题的应用尚缺少研究.对比分析多高层结构和空间网格结构动力性能差异,指出网格结构动力非线性分析存在的问题.以主振型理论和切线刚度分离法为基础,将非线性模态方法用于几何非线性效应显著的空间网格结构动力分析.通过对运动方程的非线性恢复力进行拆分,形成线性表达形式,然后解耦到主振型所在的广义坐标系,以达到缩减自由度数量的目的.并通过实例验证非线性模态方法的高效性与适用性.

关键词： 野钓   线组   饵料   浮标信号   水体含氧量   提竿   钓时   动作  

摘要： 野钓时，常出现浮标信号不错，提竿却不中鱼，而浮标动作很轻微甚至没动作时，提竿却能中鱼的情况。尤其是高温时节气压低、水体含氧量不足的时候钓深水，这种情况更明显。

关键词： 开挖隧道   纵向   反应位移法   地震响应分析  

摘要： 为了探讨隧道的纵向地震响应特性,本文采用TDAPⅢ软件,结合反应位移法对日本一地下交通隧道A号线的开挖段进行纵向地震响应分析。通过建立合理的隧道模型,考虑土与隧道结构之间的相互作用,探讨了隧道中连接设计对地震响应的影响,得到了隧道结构的内力和变形。分析结果表明:在地震作用下,隧道结构剪力、连接弹簧剪切变形量及其张开量均未超过相应限值,而结构的弯矩在389 m处测点附近非常接近限值,应当将此处作为抗弯薄弱位置并加强该处的抗弯性能。

关键词： 校园文化建设   统战文化   统一战线   创新   影响力   社会主义事业接班人   统战思想   团结友爱  

摘要： 为弘扬统战文化，筑牢统战思想根基，培育爱国爱党、团结友爱、积极奋进的社会主义事业接班人，荣昌县立足本地统战文化建设和校园文化建设实际，创新开展“统战文化进校园”活动。此活动在我县已实践五年，经过五年的有组织有计划的试点与推广，目前已形成广覆盖、多层次、有深度、具特色的校园统战新格局，有效的丰富了校园文化内涵，宣传了统战文化思想，争取了统战新生力量。

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： 文中以大广29标采用的小箱梁为研究对象,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各片小箱梁(对应为弹性支承)的横向影响线,得到小箱梁的横向分布系数,并与修正的偏心压力法、刚接梁法、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,说明此法的可行性和准确性。

关键词： 泵站结构   有限元动力分析   安全性态   应力响应   变形响应  

摘要： 泵站结构的动力分析对评价泵站安全性态具有重要意义。阐述了泵站结构动力分析的基本原理,并借助Hypermesh建立其有限元模型,利用***的动力分析功能,结合实测振动激励,计算并分析了结构稳定运行工况下主要部位的应力与变形响应,对结构的安全性态进行了评价。

关键词： 军民融合   三线军工企业   转型升级   影响因素  

摘要： 借鉴已有研究文献,构建了三线军工企业转型升级路径演进模型,结合实际案例,得出我国三线军工企业转型升级的主要路径,进而从理论和实证两个方面分析了影响三线军工企业转型升级路径选择的主要因素。

关键词： 桥面不平度   车桥耦合   虚拟激励法   精细积分法   动态影响线  

摘要： 将传统的静态影响线概念推广到动态影响线范围,研究了在车辆荷载和桥面随机不平度的作用下,简支梁桥和3跨弹性支承梁桥跨中挠度的动态影响线.基于虚拟激励法将桥面不平度转化为确定性的简谐激励,并采用精细积分法对车桥系统方程求解,获得了桥梁跨中挠度动态影响线的均值和标准差.基于3σ法则构造虚拟激励输出响应的确定值计算方法,获得了桥梁挠度动态影响线的确定性值域.最后通过算例分析了桥梁动态影响线的随机特性和车速与桥面不平度等级变化对桥梁动态影响线的影响,并研究了简支梁桥和弹性支承梁桥在随机振动作用下的动态影响线差异.

关键词： CHO cell lines   Glycosaminoglycans   Heparanase  

摘要： Glycosaminoglycans (GAG) play a ubiquitous role in tissues and cells. In eukaryotic cells, heparan sulfate (HS) is initially degraded by an endo-beta-glucuronidase called heparanase-1 (HPSE). HS oligosaccharides generated by the action of HPSE intensify the activity of signaling molecules, activating inflammatory response, tumor metastasis, and angiogenesis. The aim of the present study was to understand if sulfated GAG could modulate HPSE, since the mechanisms that regulate HPSE have not been completely defined. CHO-K1 cells were treated with 4-methylumbelliferone (4-MU) and sodium chlorate, to promote total inhibition of GAG synthesis, and reduce the sulfation pattern, respectively. The GAG profile of the wild CHO-K1 cells and CHO-745, deficient in xylosyltransferase, was determined after [S-35]-sulfate labeling. HPSE expression was determined via real-time quantitative polymerase chain reaction. Total ablation of GAG with 4-MU in CHO-K1 inhibited HPSE expression, while the lack of sulfation had no effect. Interestingly, 4-MU had no effect in CHO-745 cells for these assays. In addition, a different enzyme location was observed in CHO-K1 wild-type cells, which presents HPSE mainly in the extracellular matrix, in comparison with the CHO-745 mutant cells, which is found in the cytoplasm. In view of our results, we can conclude that GAG are essential modulators of HPSE expression and location. Therefore, GAG profile could impact cell behavior mediated by the regulation of HPSE.

关键词： Dibenzo[def,p]chrysene   PIKK inhibitors   DNA damage signaling   HepG2  

摘要： The effect of inhibitors of phosphatidylinosito1-3-kinase related kinases (PIKK): ataxia-telangiectasia mutated (ATM), ATM- and Rad3-related (ATR) and DNA-dependent protein kinase (DNA-PK) on the response of HepG2 human liver cancer cells to dibenzo[def,p]chrysene (DBC) was investigated. High cytotoxicity of DBC (IC50=0.1 mu M) was observed after 72 h incubation. PIKK inhibitors: KU55933 (5 mu M), NU7026 (10 mu M) or caffeine (1 and 2 mM) when used alone did not significantly influence the cytotoxicity. However, two combinations: KU55933/NU7026 and caffeine/NU7026 significantly increased HepG2 viability (by 25%) after treatment with DBC at 0.5 mu M. The cytoprotective effect was confirmed by cell cycle and apoptosis/necrosis analysis. DNA damage level after exposure to DBC assessed by comet assay (single strand breaks) showed a long persistence and significant decrease after incubation of the cells in the presence the inhibitors (the combination of KU55933 + NU7026 showed the strongest effect). Weak induction of reactive oxygen species (ROS) by DBC (0.5 mu M) was observed. Although, KU55933 and NU7026 when used alone did not increase ROS levels in the cells, their combination induced the ROS increase and moderately enhanced ROS generation by DBC. We propose a mechanism how cells with damaged DNA after exposure to DBC and under the condition of PIKK inhibition, may be at higher risk of undergoing malignant transformation. (C) 2015 Elsevier B.V. All rights reserved.