某工程砂卵石地基施工实践

结合山西师大科学实验楼工程实例 ,经分析其场地工程地质条件及施工难点后 ,确定了砂石地基垫层施工方案及施工顺序 ,并对施工中出现的具体问题提出了相应的解决措施     

Granzyme B mimics apical caspases. Description of a unified pathway for trans-activation of executioner caspase-3 and -7

Granzyme B (GrB) is predicted to trigger apoptosis by activating preferred caspases, but the zymogens that are directly processed by the granzyme and the requirements for these interactions remain unclarified. We examined this dilemma by comparing the kinetics and pattern of GrB-mediated activation of the executioner caspase-7 in vitro and in vivo. GrB rapidly activates procaspase-7 in vitro by cleaving between the large and small subunits leaving the propeptide intact. During GrB-mediated apoptosis, the caspase-7 propeptide is removed and cleavage occurs between the subunits. Strikingly, caspase-7 is unprocessed in caspase-3-deficient MCF-7 cells exposed to GrB but is rapidly activated when the cells are solubilized. Transfection with caspase-3 restores the removal of the caspase-7 propeptide and the capacity of GrB to subsequently activate the caspase. The data suggest that GrB activates caspase-3, which then removes the propeptide of caspase-7 allowing activation by GrB. Thus GrB initiates the death pathway by processing the accessible caspase-3, and the caspase-7 propeptide regulates trans-activation of the zymogen by granzyme. As a consequence, two proteases, caspase-3 and GrB, are required to activate procaspase-7.     

Changes in agonist-antagonist EMG, muscle CSA, and force during strength training in middle-aged and older people

Serotonin (5-HT) is one of the major transmitters involved in supraspinal control of somatic sensation and nociception. The aim of the present study was to investigate if the 5-HT-induced modulation of sensory transmission in the dorsal horn could be due to regulation of neuronal responses to excitatory amino acids. Experiments were performed in an in vitro preparation of the young rat spinal cord. Responses to dorsal root stimulation (DR-EPSP) and to droplet application of N-methyl-D-aspartic acid (NMDA) and alpha-amino-2,3-dihydro-5-methyl-3-oxo-4-isoxazolepropanoic acid (AMPA) were obtained by means of intracellular recordings of dorsal horn neurons. Bath applications of 5-HT (50 microM) generally caused reductions in amplitude and integrated area of DR-EPSPs and of responses to NMDA but the responses to AMPA were unaltered. A linear correlation was found between the effects of 5-HT on the DR-EPSP and on the NMDA response measured as percentage change in amplitude (r2 = 0.45; P < or = 0.01) and integrated area (r2 = 0.77; P < or = 0.001). The NMDA receptor antagonist d-AP5 (50 microM) completely abolished NMDA responses and caused a depression of the DR-EPSP similar to that of 5-HT. The 5-HT1 receptor agonist 5-carboxamidotryptamine (5-CT; 1 microM) mimicked the depressant effects of 5-HT but had a stronger depressant action on the DR-EPSP than 5-HT. The depression of NMDA responses induced by 5-HT and 5-CT was tetrodotoxin (1 microM) resistant. It is concluded that 5-HT-induced depression of NMDA responses explains partially the depressant action of 5-HT on dorsal horn synaptic transmission activating a postsynaptic site sensitive to 5-CT. The possible activation of coadjuvant mechanisms is discussed.     

旋切机旋刀后角的模拟研究

通过计算机建模方式综合考虑了装刀高度、单板厚度及起始半径等初始参数,采用OpenGL设计了一个Windows程序来计算第二类刀架上旋切后角并反映其变化情况,这可以为设计旋切机刀架提供依据,为合理调整偏心距,提高旋切单板质量提供新的方法。     

土-桩-桥相互作用的集中质量模型的比较研究

在进行桥梁抗震分析中，为了得到较为符合实际情况的桩基础的地震反应分析结果，必须考虑土和结构的相互作用。集中质量模型是群桩基础抗震计算中广泛采用的简化计算模型。本文以此模型为基础，讨论了复杂程度不同的集中质量模型的精度，主要讨论土层特性、群桩数目、群桩间距、桩长等因素对简化模型的精度影响。     

STFT与SOPC技术相结合实现高速跳频图案的识别与跟踪

本文根据频率跟踪式干扰的基本原理,提出一种基于短时傅里叶变换 (STFT)的高速跳频图案的识别与跟踪方案,并采用可编程芯片系统 (SOPC)技术进行了硬件实现。理论分析与实测结果表明,该系统实现 1024点的STFT仅需 84μs,可对 10 000跳 /秒以下的高速跳频图案实时识别与跟踪。     

环境信息资源整合的初探

文章分析了中国环境信息整合的需求,阐述了电子政务中环境信息整合的概念、模式和实现面向环境信息的整合与环境信息共享.说明在中国现阶段的电子政务建设中,合理有效地开发和利用信息资源是其核心内容,而进行更全面的电子政务建设的基础就是环保信息资源的建设与整合.     

瞬间的映像当代艺术对中国现代进程的应对

关注"当下"这个瞬间是中国当代艺术的核心,由此产生的当下性引入了新的颓废维度,并以自我边缘化的否定态度界定与其他艺术流派的关系.当前的现代化进程带来的高速都市化、大众社会与消费引导下的美学几个特点,冲击着艺术创作与批评、收藏.作为应对,艺术与建筑重申对空间的拥有;强化自身的个体性;关注弱势群体;展现市场的权力意志以及在互动中满足观众的艺术参与.这几种方式摹写出当下的瞬间映像,并逐步地发展出面对未来的新视野.     

基于因子分析的创城满意度模型研究——以冬奥会背景下张家口市为例

在京张联合举办2022年冬奥会和科学建设文明城市的背景下,为了掌握影响张家口市创城的影响因素,准确预测出未来张家口文明城市建设情况,.建立了张家口创城满意度指标评价体系并设计发放调查问卷,对回收数据采用SPSS软件,建立因子分析模型,得到创城满意度影响因子,对张家口的县地区得分做出排名并评价,建立回归分析模型,从生活、生态、市场、法治和政务环境分析对创城满意度的影响,找到张家口市文明城市建设存在的主要问题,提出改善创城满意度建议,为冬奥会创造良好的城市环境。