Differential effects of monastrol in two human cell lines

The kinesin-related protein HsEg5 plays essential roles in mitotic spindle dynamics. Although inhibition of HsEg5 has been suggested as an aid in cancer treatment, the effects of such inhibition on human cells have not been characterized. Here we studied the effects of monastrol, an allosteric HsEg5 inhibitor, on AGS and HT29 cell lines and compared them to those of taxol. While both cell lines were similarly sensitive to taxol, AGS cells were more sensitive to monastrol. The differences in sensitivity were determined by the degree of inhibitory effect on cell proliferation, reversibility of monastrol-induced G2/M arrest, intracellular phenotypes and induction of apoptosis. In both cell lines, monastrol-induced apoptosis was accompanied by mitochondrial membrane depolarization and poly-ADP-ribose polymerase 1 cleavage. In AGS, but not HT29 cells, monastrol-induced apoptosis involved a prominent cleavage of procaspases 8 and 3. While in AGS cells, monastrol induced the formation of symmetric microtubule asters only, in HT29 cells, asymmetric asters were also formed, which may be related to specific HsEg5 functions in HT29 cells.Received 18 February 2004; received after revision 30 May 2004; accepted 16 June 2004     

旋转球的动力学分析

角球在飞进中产生了两种压差阻力,在其合力的作用下,球体被迫改变了正常的轨道,从而形成了“香蕉形”的轨迹。     

主轴结构优化的有限元方法

利用有限元分析软件ANSYS计算数控镗铣钻床主轴的静态变形与一阶固有频率。在ANSYS中利用APDL语言实现主轴有限元模型的参数化,并对主轴的结构进行优化设计,求出了主轴优化后的主要结构参数。分析结果表明,采用优化的主轴参数不但降低了主轴自重而且提高了主轴的刚度和临界转速,使主轴在结构方面更加合理、安全。     

抽水蓄能电站在发电工况下旋转备用效益的测算

以抽水蓄能电站各项辅助服务中最为重要一项———旋转备用辅助服务为对象,利用蒙特卡罗随机生产模拟技术,研究抽水蓄能电站最优抽水策略下发电工况下旋转备用容量的定价理论,给出了以边际成本确定旋转备用容量电价的模型方法,以及抽水蓄能电站在发电工况下旋转备用的效益模型。并结合算例说明了模型的正确性和合理性。目的在于使各厂家在发电工况下机组提供备用时能够在提供电能和提供备用之间作出合理的选择,充分体现出其容量的市场价值,使旋转备用的效益达到最优。     

变频调速技术在细纱机恒张力控制中的应用

根据纱线长度，用变频器控制细纱机主轴转速，设计了纺纱过程中纱线恒张力控制．程序按照状态变化进行设计开发．实验结果表明，该设计达到设计要求．其产品已投入批量生产．     

The Yarn Curve and Tension in Rotor Spinning

The effective way of finding the yarn curve shape and tension of OE（open end） yarn inside the rotor is carried out and treated by dividing the yarn curve into two parts, from which the trajectory of the yarn sliding on the navel surface is also obtained. It is pointed out that the yarn curve shape and tension will both fluctuate with the trajectory＇s revolving cycle inside the rotor. However, the fluctuation is not too great, so the motion can still be regarded as approximately steady for dynamic analysis.     

两种不同形状旋转带对气液两相流场影响的计算流体力学模拟

利用计算流体力学软件FLUENT,以RNGk-ε湍流模型和Eulerian多相流模型对旋转带蒸馏设备内的流场进行了数值模拟.模拟考虑了旋转带的结构因素.结果表明,无开孔的旋转带在高速转动时,设备内的流体会产生界面分离现象,不利于气液两相的密切接触.而有开孔的旋转带在高速旋转时,会有效地改善流体界面的分离,而且气液两相的湍动程度更大,这些现象将有利于气液两相的传质.同时,比较了开孔位置和孔径大小对改善气液界面分离的影响.模拟结果为进一步研究旋转带蒸馏设备的结构优化和操作提供了理论依据.     

Analysis and Discussion of Fiber Motion in the Spinning Triangle of Ring Spinning

In order to analyze the effect of the spinning triangle on yarn structure,a shape model of the spinning triangle is established.The fiber motion in the spinning triangle can be divided into three stages,and the relationship between yarn structure and fiber duration as well as the force acting on the fibers in the three stages is analyzed.The fiber elongation in different location of the spinning triangle is variational.The difference is that the elongation of fiber in the middle spinning triangle is bigger than that in the edge of it and the difference will be amplified with the increase of spinning triangle width,which has an effect on the characteristic of yarns structure.Research results for further study on compact yarn structure and improving spinning frame structure provide theorybasis.     

横向机动控制固体火箭发动机的冲量效率(英文)

对安装在旋转飞行器上实现横向机动控制的固体火箭发动机的冲量效率进行了分析,导出了计算冲量效率的解析式,并对计算结果进行了讨论。用本方法获得的冲量效率的计算值与参考文献提供的数值十分接近。     

空心锭子差捻包缠纱捻度作用研究

简述了空心锭子差捻包缠纱的成纱过程，论述了空心锭子差捻包缠纱的包缠捻度、加捻捻度对纱线性能的影响。