被动运动和电刺激对失神经大鼠股骨生物力学性能影响的研究

目的:探讨被动运动和电刺激对失神经大鼠股骨生物力学性能的影响。方法:切断大鼠坐骨神经和股神经,造成失神经支配大鼠废用性骨质疏松模型,并随机将大鼠分为假手术组、对照组(NCG)、被动运动组(PMG)、电刺激组(ESG)和被动运动 电刺激组(PMESG)5组,观察各组大鼠股骨生物力学指标的变化。结果:与假手术组比较,其余各组股骨弹性模量、极限强度、结构刚度、最大载荷、能量吸收均显著性降低(P<0.05),最大应变值显著性升高(P<0.05);与对照组比较,各组弹性模量、极限强度、结构刚度、最大载荷、能量吸收均显著性升高(P<0.05),最大应变值除被动运动组仅见降低趋势外(P>0.05),其余各组均显著性降低(P<0.05)。结论:大鼠失神经支配可引起股骨生物力学性能下降,电刺激和被动运动治疗可减缓失神经大鼠股骨生物力学性能的改变。因此,被动运动和电刺激能有效预防失神经所致的废用性骨质疏松,二者联合作用效果更佳。     

中国城乡数字鸿沟对城市化进程阻尼系数估算

借鉴粘滞摩擦学中阻尼系数概念,建立中国城乡数字鸿沟对城市化进程阻尼系数测度模型,运用非参数估计方法对阻尼系数进行估计。研究发现:阻尼系数逐点估计值围绕总体估计值0.07695在区间[0.06898,0.08799]内小幅波动,说明城乡数字鸿沟对城市化进程动力的耗损是其固有的一种能力;城乡数字鸿沟对科技进步动力的耗损远大于对经济发展动力的耗损,通过经济发展加快城市化进程更为"划算"。     

持续被动运动通过抑制软骨细胞NO合成下调MMP-1和MMP-13表达

目的:观察持续被动运动(CPM)和补充一氧化氮(NO)供体——硝酸甘油(NG)对兔骨关节炎(OA)模型中软骨基质金属蛋白酶-1(MMP-1)和MMP-13表达以及NO含量的影响,探讨CPM下调MMPs的可能机制。方法:30只3~4月龄雄性新西兰大白兔,其中6只进行假手术作为正常对照组(NC组),另外24只建立膝关节OA模型,术后随机分为4组,即OA对照组(OA组)、OA硝酸甘油给药组(NG组)、OA持续被动运动组(CPM组)、OA持续被动运动+硝酸甘油给药组(CPM+NG组),每组各6只。NC组和OA组不作处理,NG组给予NG软膏膝关节局部涂抹,CMP组在CPM训练仪上进行膝关节持续被动运动,CMP+NG组即在运动干预的同时给予NG局部涂抹。4周后取各组软骨组织,硝酸还原酶法测定NO含量,HE染色观察软骨形态学变化并进行Mankin’s评分,实时荧光定量PCR(RQ-PCR)检测MMP-1和MMP-13 mRNA水平,免疫组织化学法测定MMP-1和MMP-13蛋白表达量。结果:NO含量、Mankin’s评分以及MMP-1和MMP-13 mRNA和蛋白水平在OA组明显高于NC组(P<0.01),NG组高于OA组(P<0.01),CPM组低于OA组和NG组(P<0.01),CPM+NG组低于NG组(P<0.01),但高于CPM组(P<0.01)。结论:CPM通过抑制软骨细胞NO合成下调MMP-1和MMP-13表达,进而对软骨细胞起保护作用。     

The influence of the hand’s acceleration and the relative contribution of drag and lift forces in front crawl swimming

The aim of this study was to assess the effect of the hand’s acceleration on the propulsive forces and the relative contribution of the drag and lift on their resultant force in the separate phases of the front crawl underwater arm stroke. Ten female swimmers swam one trial of all-out 25-m front crawl. The underwater motion of each swimmer’s right hand was recorded using four camcorders and four periscope systems. Anatomical landmarks were digitised, and the propulsive forces generated by the swimmer’s hand were estimated from the kinematic data in conjunction with hydrodynamic coefficients. When the hand’s acceleration was taken into account, the magnitude of the propulsive forces was greater, with the exception of the mean drag force during the final part of the underwater arm stroke. The mean drag force was greater than the mean lift force in the middle part, while the mean lift force was greater than the mean drag force in the final part of the underwater arm stroke. Thus, swimmers should accelerate their hands from the beginning of their backward motion, press the water with large pitch angles during the middle part and sweep with small pitch angles during the final part of their underwater arm stroke.     

英汉广告语篇物质过程结构表达方式对比分析

通过实例对比分析英汉广告语篇小句层面物质过程结构表达方式,发现受英汉语言本体性质及价值、思维趋势的影响,两种语篇中物质小句具有相同的语义成分结构,但构成序列迥异;英语被动物质过程小句呈现出静、动两种态势,汉语被动物质小句只表动作行为,不表状态。     

中动结构定位再思考：被动乎？转喻乎？——结构对中动词的重塑

中动词是语言学中的“特殊”现象,学界不乏中动词的研究,被动乎？转喻乎？至今对中动词仍无明确定位。有的语言学家认为中动词与“被动”语态相联系,是主动形式表达被动意义;也有的学者试图用认知语言学的构式语法及其转喻理论对中动结构予以全新解释。对中动词的定位究竟应从结构（形式）视角,还是语义视角呢,本文试图对中动词现象的定位作进一步的思考,并提出中动词词汇化假说和同形词假设,以期对中动词以合理定位。     

论儒家思想对中国传统体育竞技性的消极影响

从儒学中庸、实用主义、严格的等级制度和道德观念以及“复古”、“守陈”四个方面阐述了儒家思想对中国传统体育竞技性的消极影响,以期为中国传统体育竞技性的发展提供借鉴.     

英语中的主动结构被动意义

文章讨论了英语中某些动词的主动形式表示被动意义的语言现象     

A method for personalising the blade size for competitors in flatwater kayaking

The intent of this project was to explore the feasibility of personalising the paddle blade size for individual flatwater kayakers based on their power output profiles. Twelve elite male kayakers performed on a kayak ergometer at the same intensity and resistance that they would normally experience while paddling at race pace for 500 m on the water. The kayak ergometer was instrumented so that power profiles could be determined from the instantaneous force and velocity of the representative centre point of the paddle blade. From the power profile information, the researchers calculated a personalised blade size that was expected to improve performance for those kayakers differing more than 5% from the calculated ‘ideal’ size. For the elite kayakers studied, it was recommended that seven of the paddlers should increase their blade size by approximately 5–10%. For the remaining five paddlers, the results indicated that their current blade sizes were within the expected measurement error of their predicted ideal value and should be retained. It is anticipated that this research will provide the theoretical rationale for elite kayakers to see the need to personalise their blade size based on their own muscle power profiles.     

中国就业政策评价:1998-2008

从消极就业政策到积极就业政策的转变,标志着中国政府以更为积极的姿态来处理就业问题。估算结果表明,1998-2008年,我国政府为落实就业政策累计支出6169.67亿元,其中用于落实消极就业政策的支出为4144.06亿元,落实积极就业政策的支出为2025.61亿元。实证分析发现,落实积极就业政策的支出和落实消极就业政策的支出与下岗失业人员的再就业之间存在长期稳定关系,落实积极就业政策的支出每变动1%会导致下岗失业人员的再就业数量同向变动0.27%,说明我国政府用于促进就业的支出的确对再就业工作显示出了积极作用;而落实消极就业政策的支出每变动1%将引起下岗失业人员的再就业数量反向变动1.05%,这一结果表明落实消极就业政策的支出吸引了更多的失业下岗人员加入失业保险体系,同时发挥出了一种"社会稳定器"的功能。