两种方式负重半蹲起训练作用差异的研究

应用肌电图仪，对田径运动员以不同动作方式进行负重半蹲起做了下肢肌电观察和记录，发现了它们对下肢各肌群训练作用的不同之处．为不同项目的田径运动员选择做负重半蹲起训练的具体方式提供了依据．     

谈艺术体操教学中的群体效应

高师体育教育专业的培养目标是合格的中学体育教师。根据中学班级人数多,每节课时间短的特点,除了教学内容、教学方法上进行改革外,本文主要在练习形式上,利用团体操中多种多样的队形、图形变化所产生的群体效应,来达到一种良好的、适宜的课堂气氛,收到较好的教学效果。     

Gene product expression of cyclin D<Subscript>2</Subscript> and p16 during the transition from cardiac myocyte hyperplasia to hypertrophy

The current study was to investigate mRNA expression of cyclin D₂ and p16 during the transition from cardiac myocyte hyperplasia to hypertrophy. Cultured cardiac myocytes (CM) and fibroblasts (FC) obtained from 1-day-old Sparague-Dawley rats were used in this study. We have determined (1) hyperplasia by cell growth curve and fluorescence activated cell sorting (FACS); and (2) ultrastructure by electron microscope observation; and (3) expresions of cyclin D₂ mRNA and p16 mRNA by using in situ hybridization and image analysis. The results were shown (1) Results of cell growth curve and FACS analysis showed CM could proliferate in the first 3 cultured days (4 days in postnatal development). But the ability decreased quickly, concomitant with the differentiation. (2) The ultrastructure of CM showed the large amount of myofilaments and mitochondrion and FC showed moderate amount of rough endoplasmic reticulum. (3) The expression of cyclin D₂ mRNA in 3−, 4−, 5−day CM group was 0.89 times (p<0.05), 0.80 times (p<0.05) and 0.56 times (p<0.01) of that in 1-day group respectively. P16 mRNA in 2−, 3−, 4−, 5−day CM group were 1.63 times (p<0.01), 1.72 times (p<0.01), 1.99 times (p<0.01) and 2.84 times (p<0.01) of that in 1−day group respectively. It can be concluded that cultured neonatal rat cardiac myocytes could proliferate during the first 3 cultured days, but the ability of proliferation decreased, from the fourth day, concomitant with differentiation. Cyclin D₂ and p16 have the key roles during the transition from myocyte hyperplasia to hypertrophy. Biography: Zhang Yu-xia (1974-), female, Master, research direction: cardiovascular pathology.     

FINITE TIME TRACKING CONTROL FOR RIGID ROBOTIC MANIPULATORS WITH FRICTION AND EXTERNAL DISTURBANCES

1.Introduction Variable structure control is well known for its robustness to system uncertainties and external disturbances and has been successfully applied to the rigid robotic manipulator systems(Utkin(1992),Zinober(1990)).Generally,a linear sliding mode is firstly designed to describe the desired system error dynamics,a robust controller drives the switching plane variables to reach the sliding mode,and the error dynamics will asymptotically converge to zero on the linear sliding mode.Si…     

仿真系统与专家系统结合方式分类方法的研究

本文首先阐述仿真系统与专家系统之间的相似与不同之处，然后从系统分类的观点将仿真系统与专家系统的结合方式进行分类。通过这种分类方法，一方面可以将目前专家系统在仿真系统中的应用．或仿真系统在专家系统中的应用归纳进某一种类别或几种类别的组合之中，另一方面又可以发现两者结合方式之中存在的问题与不足。最后，通过一个实例说明这种分类方法是怎样帮助人们发现问题并且解决问题。     

Containerless solidification of Zr41Ti14Cu12.5Ni10Be22.5 glass-forming alloy in drop tube

Droplets of Zr41Ti14Cu12.5Ni10Be22.5 glass form-ing alloys with different sizes are solidified in a drop tubecontainerless processing. Glass transition behavior, crystal-lization kinetics, and the phase evolution during annealing of the Zr41Ti14Cu12.5Ni10Be22.5 glassy spheres are investigated. The experimental results indicate that the apparent activation energy of the glass transition (Eg = 435.5 kJ/mol), and the activation energy of the main crystallization reaction (Ep1 = 249.6 kJ/mol) are obviously different from those of bulk glass samples prepared by water quenched (Eg = 559.1 kJ/mol and Ep1 =192.5 kJ/mol). The difference is discussed in the view point of the atomic configuration of the liquid state of the metallic glass and nucleation mechanism.     

对校园网络安全的研究

大学校园网具有业务覆盖范围大，信息庞大的特点，系统一旦出现问题后果不堪设想，损失无法估量。因此。校园内要求系统的稳定性、安全性、可靠性非常高。而现在的大多数校园网都与互联网建立了联接。来自互联网上的网络病毒以及校园网络内外的黑客攻击已成为网络安全的重大隐患。建立一套切实可行的校园网络安全保护措施，使校园网能够安全稳定地运行．已成为各大校园网管理者迫在眉睫的任务。     

Laplace Transformation and Ergodic Potential Kernel for q-Process in Random Environment

This paper introduces some concepts such as q-process in random environment, Laplace transformation, ergodic potential kernel, error function and some basic lemmas.We study the continuity and Laplace transformation of random transition function. Finally, we give the sufficient condition for the existence of ergodic potential kernel for homogeneous q-processes in random environments.     

EC,ASMC and Macrophage Oxidize Human Low Density Lipoprotein

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