质点组内力的功改变质心动能的条件

讨论了质点组内力的功是可以改变质心动能的，以及所满足的条件．     

Remote effects of lower limb stretching: preliminary evidence for myofascial connectivity?

The skeletal muscles and the fibrous connective tissue form an extensive, body-wide network of myofascial chains. As fascia can modify its stiffness, strain transmission along these meridians is supposable. The goal of this trial therefore was to collect pilot data for potential remote effects of lower limb stretching on cervical range of motion (ROM). Twenty-six healthy participants (30 ± 6 years) were included in the matched-pairs intervention study. One group (n = 13) performed three 30 s bouts of static stretching for the gastrocnemius and the hamstrings, respectively. An age- and sex-matched control group (CG; n = 13) remained inactive. Pre- and post-intervention, maximal cervical ROM in flexion/extension was assessed. A repeated measures ANOVA revealed systematic differences between groups (P < .05). ROM increased following stretching (143.3 ± 13.9 to 148.2 ± 14°; P < .05) but remained unchanged in the CG (144.6 ± 16.8 to 143.3 ± 16.8°; P > .05). Our data point towards existence of a strain transfer along myofascial meridians. Further randomised controlled studies on conditions, factors and magnitude of tensile transmission are warranted.     

卢瑟福模型中电子运动分析

关于卢瑟福模型中电子的运动是加速还是减速,不同文献给出不同描述,甚至是截然相反的描述.本文分别从能量和力的角度定量、定性地分析了卢瑟福模型中电子的运动情况,得出了卢瑟福模型中电子绕原子核旋转、辐射能量时作加速运动的结论.     

以创建精品开放课程为契机,加强教学模式和教学方法改革

2012年,安徽中医药高等专科学校创建精品开放课程,此课程开放以来在教学模式和教学方法改革方面取得了建设的进步,但是在精品课程的开放中还存在很多问题。     

浅谈高等学校内部审计信息化建设

ZHU Ling-e(North China University of Technology,Beijing 100144,China)     

试析当前湖北劳动力素质结构

近年来，湖北经济增长率结束了长时期的下降而开始出现回升，经济发展的状况对全省劳动力就业形势构成了较大影响。表现为经济结构的调整带来了就业形势的变化，并进而影响劳动力素质结构的变化。     

基于信息技术的高校内部审计及其实现架构研究

高等院校内部审计是其内设的审计机构从内部对其财务收支的真实性、合法性和效益性进行的审计监督。本文介绍了内部审计的概念、国内外现状与发展,剖析了高等院校内部审计的特点,比较了传统的内部审计与基于信息技术的内部审计,分析了信息技术在内部审计中的重要作用,提出了基于信息技术的高等院校内部审计的实现架构,对实现普通高等院校和高职高专院校内部审计的信息化具有一定的指导意义。     

The influence of shoe drop on the kinematics and kinetics of children tennis players

This study investigated the immediate effects of reducing the shoe drop (i.e. the difference between the heel and the forefoot height) on the kinematics and kinetics of the lower extremities of children tennis players performing a tennis-specific movement. Thirteen children tennis players performed a series of simulated open stance forehands wearing 3 pairs of shoes differing only in the drop: 0 (D0), 6 (D6) and the control condition of 12?mm (D12). Two embedded forceplates and a motion capture system were used to analyse the ground reaction forces and ankle and knee joint angles and moments of the leading lower limb. In D6 compared with D12, the peak impact force was reduced by 24% (p?=?.004) and the ankle was less dorsiflexed at foot strike (p?=?.037). In D0 compared with D12, the peak impact force was reduced by 17% (p?=?.049), the ankle was less dorsiflexed at foot strike (p?=?.045) and the knee was more flexed at foot strike (p?=?.007). In addition, 4 out of 13 participants (31%) presented a forefoot strike pattern for some of the trials in D0. No difference was observed across shoe conditions for the peak knee extensor moment (p?=?.658) or the peak ankle plantarflexor moment (p?=?.071). The results provide preliminary data supporting the hypothesis that for children tennis players, using a 6-mm lower shoe drop might reduce heel impact forces and thus limit potentially impact-related injuries.     

试论塑造大城市的三种力量及其博弈

经济力量、政治力量和社会力量是塑造大城市发展模式的三种基本力量。经济力量是城市发展的物质基础；社会力量是重要推动力；政治力量则起着关键的中介作用。正是这三种力量的结合、互动和博弈塑造了大城市的空间结构和发展模式。在政治、经济和社会的和谐中构建有中国特色的大城市发展模式是当前中国大城市的发展方向和根本路径。