跑步再训练对髌股疼痛综合征跑者髌股关节压力的影响

跑步运动损伤的发生率很高,其中髌骨疼痛综合征是最常见的膝关节损伤疾病。通过改变跑步时跑者的落地模式和步频来修正异常的下肢生物力学目前受到越来越多学者的关注。研究目的为针对跑步再训练后跑者髌股关节应力的变化,综述跑步再训练后跑者髌股关节生物力学变化的研究和进展。目前研究已证实通过改变跑步落地模式和步频能够对髌股关节生物力学产生影响,但是针对患有髌骨疼痛综合征跑者的即刻效应的研究较少,且对于同时改变步频和落地模式的效果存在一定争议,未来需进一步探讨髌骨疼痛综合征跑者的跑步再训练效果。     

高水平运动员组织性应激影响因素的质性研究

为深入了解高水平运动员的组织性应激影响因素,从组织层面更好地关注运动队和运动员的健康可持续发展,降低组织性应激对高水平运动员操作成绩的影响,运用质性研究方法,通过对16名高水平运动员在训练比赛过程中出现的组织性应激反应进行深度访谈,使用内容分析软件QSR NViovo 11.0对采录的运动员谈话内容进行分析。结果显示：高水平运动员组织性应激影响因素可分为环境因素、个人因素、领导因素和团队因素等4类;其中领导因素（116）是运动员组织性应激的最大应激源,其次是团队因素（114）和环境因素（112）,个人因素（58）最小;在二级指标中,教练员因素（96）对运动员组织性应激影响最大,其次是团队氛围（50）和选拔机制（43）。因此,呼吁运动队管理者、教练员等重视组织层面给运动员带来的困惑和压力,建议运动心理工作者就运动队组织性应激问题进行深入研究,加大对运动员组织性应激的关注和调节,促进我国高水平运动队和运动员的健康发展。     

公开水域游泳运动的生理学研究进展

为公开水域游泳运动的选材、训练和比赛提供参考依据,提高我国公开水域游泳运动的发展水平,采用文献综述法,概述国内外公开水域游泳运动员ACE基因I/D多态性特征、低体温症、热应激以及运动性低钠血症的研究进展,相关研究结果发现： ACE-I等位基因是决定耐力素质的关键因素,5-10km公开水域游泳运动员与马拉松长跑运动员的ACE-I等位基因存在较大差异,但可能与室内游泳项目运动员相似;皮褶厚度影响机体隔绝外界低温的能力;下丘脑的体温调节中枢可作为个体出现低体温症的影响因素之一;游泳运动员的这种低汗率高但高Na+和Cl–的出汗适应性可能是导致游泳运动员在公开水域进行长时间游泳时出现低钠血症的主要原因之一。     

浅谈体操教学中恐惧心理的克服

在体操教学中,学生常常会产生恐惧心理,严重影响体操的教学质量。本文采用文献法和系统分析法,阐述了恐惧心理的基本特征和产生原因,并从教学的主体和主导两个方面提出了恐惧心理的预防措施,紧紧围绕恐惧心理的特征提出了克服恐惧心理的方法,以供同行在教学中和学术讨论中参考。     

Effects of material properties of cue on impact behaviour in follow and draw shots in billiards

The effective numerical method proposed by Shimamuraet al. (2007) is extended to predict the ball motion in a draw shot as well as a follow shot in billiards. The extended method is verified experimentally using a high speed camera. It is observed in the experiment that a ball rotates backwards with a lot of slip (between ball and table) at first and then rotates forwards in a draw shot. Such a ball motion is predicted quantitatively with the numerical method. Numerical simulations are performed to investigate the effects of material properties of a cue on ball behaviour in follow and draw shots and it is found that the impact force increases with increasing stiffness of the shaft in both follow and draw shots, while its duration time is shortened with increasing wave velocity in the shaft for both shots. It is also found that there is a certain shaft stiffness that gives the minimum ball centre velocity, the minimum angular velocity, the minimum slip velocity between ball and table and also the minimum time when the backward rotation changes to a forward one in a draw shot, while the ball centre velocity and the angular velocity increase with increasing shaft stiffness in a follow shot.     

大学生热环境下中等强度运动的热调节反应和生理变化

为探讨大学生热环境下运动的热调节能力和生理变化情况。将18名男性大学生自愿者随机分为热环境运动组(HE组)和室温对照组(NE组),以55%VO2max强度分别在38±1℃和26±1℃环境下(相对湿度皆为73%±3%)进行60min功率自行车运动。每15min测定两组HR、RPE值和直肠温度,统计热环境下HR和RPE的相关关系;测定两组运动前后的体重变化、总出汗率、总出汗量、血尿素和疲劳指数。结果得出:两组被试运动15min HR、RPE组间差异不显著,但30min后HE组HR、RPE值显高于NE组并持续到运动结束;热环境下HR与RPE呈高度相关(r=0.839,P<0.01);运动过程中,NE组Tre低于HE组,运动30min后差异愈发明显;运动前后NE组体重丢失、总出汗量、总出汗率均低于HE组(P<0.05),BUN和FI明显低于HE组(P<0.01)。结论为:热环境下运动对HR、RPE、Tre的刺激更为深刻,并且体重丢失、脱水更为严重,更易导致肌体疲劳。     

水轮机叶片铸造与热处理缺陷分析及防止

本文分析了水轮机组叶片铸造缺陷的产生原因和防止措施,水轮机组不锈钢叶片铸造裂纹的形成是由于铸造热应力和组织应力过大,超过材料的抗拉强度,通过对铸态下的金相组织分析,找出了水轮机叶片铸造与热处理缺陷产生的原因,并提出了改进措施。     

Predictors of foster parents’ stress and associations to sensitivity in the first year after placement

In Germany, almost 70 000 children are living in foster families (Statistisches Bundesamt, 2016). Many foster children show mental health problems as they were exposed to an accumulation of risk factors. Hence, foster parents are often faced with challenging parenting situations. The current study focuses on the predictors of foster parents’ stress and examines longitudinally whether parenting stress is associated with foster parents’ sensitivity. The sample consisted of 55 children (aged from 1 to 6 years) and their foster caregivers. Foster parents’ sensitivity was observed during home visits. Caregiver reports were used to assess parenting stress (Parenting Stress Index) as well as foster children’s externalizing behavior problems (Child Behavior Checklist). For main caregivers’ stress at the beginning of placement, regression analyses revealed both, foster children’s externalizing problems as well as partners’ stress as predictive. For main caregivers’ stress one year after, only initial parenting stress and partners’ stress were predictive. Foster parents’ sensitivity was correlated with their parenting stress one year after placement. Regression analyses revealed no longitudinal effects of initial parenting stress on overall sensitivity. However, supportive presence was predicted by initial supportive presence and by the interaction between parenting stress and children’s externalizing problems at placement. The findings highlight the role of the partner in experiencing parenting stress when taking care of a foster child. Furthermore, they emphasize that foster parents who care for children with behavior problems need adequate support that can buffer initial parenting stress and thereby promote sensitive caregiving.     

Verifying the operation of an elastic crossbar system applied to a panel painting: the Deposition from the Cross by an anonymous artist from Abruzzo,sixteenth century

This study deals with the post-treatment evaluation of the elastic crossbar system already designed and installed on the recently restored panel painting Deposition from the Cross by an anonymous artist from Abruzzo (sixteenth century). After the restoration, the panel and the crossbars were subjected to mechanical tests to identify their elastic characteristics. Then the panel, equipped with the elastic crossbar system, was subjected for about two months to controlled environmental cycles made up of approximately constant humidity periods. During the two months, the forces exerted by the springs and the deformations of both panel and crossbars were continuously monitored. A mathematical model, calibrated on the specific parameters derived from the analysis of the panel, provided the deformation that the panel would have shown without the crossbars; comparing the model output with the measured data provided a restraining effect (RE) of approximately 7% (RE could range between zero – no restraint – and 100% – total restraint). Future developments of this project will define appropriate procedures to design an elastic crossbar system for a given panel, once the expert judgement of restorers has identified the most desirable RE to be achieved.     

粉体贮存的闭塞及解决措施

通过粉体在上为圆筒、下为圆锥形料仓中的应力分析 ,得出了不发生闭塞的最小卸料口尺寸 ,结合实际情况提出了解决粉体闭塞的措施