生态脆弱区社会经济与资源环境耦合协调度研究:以云南省昭通市为例

对于生态脆弱地区,探寻其社会经济发展与资源环境的协调发展模式对于实现地区的可持续发展具有重要意义。构建相对资源承载力模型和耦合协调度模型,测算云南省昭通市相对资源人口承载力和经济承载力,并对"经济-资源环境-社会"系统协调发展度进行时空分析。结果表明：1）昭通市相对资源人口承载力超载严重,社会资源承载力低且显著超载;2）相对资源经济承载力处于富余状态,资源的经济价值尚未充分开发;3）昭通市社会经济发展受资源环境制约显著,系统不协调度有拉大趋势。提高第二产业发展水平,优化产业结构是促进昭通市"经济-资源环境-社会"系统协调发展的主要措施。     

Effectiveness of physical education to promote motor competence in primary school children

Background: Motor skill (MS) competence is an important contributing factor for healthy development.

Purpose: The goal was to test the effectiveness of primary school physical education (PE) on MS and physical fitness (PF) development.

Methods: Three classes (n?=?60, aged 9.0?±?0.9) were randomly assigned to three diverse conditions during a school year: two PE lessons/week (PE-2), three PE lessons/week (PE-3), and no PE lessons control group (CG). BMI, skinfolds, PF (9-min run/walk, sit-up, modified pull-ups), gymnastics, soccer, handball, basketball and track-and-field skills were evaluated. Effect sizes (d) were reported as magnitude of change.

Results: Skinfolds significantly increased only in CG (d?=?1.21). PF composite z-scores improved in PE-3 (d?=?0.61), but decreased in PE-2 (d?=?0.57), and had no changes in CG. Statistically significant improvement was verified in gymnastics and handball skills in both experimental groups (gymnastic: d?=?2.95 and d?=?2.61 for PE-3 and PE-2, respectively; handball: d?=?1.87 and d?=?0.57 for PE-3 and PE-2, respectively), and no changes were seen in CG. In soccer, there were improvements only in the PE-3 (d?=?0.55), and in basketball only in PE-2 (d?=?0.46). There were no changes in any group for track-and-field skills.

Conclusions: PE programs can effectively promote PF and MS development.     

Changes in kinematics and arm–leg coordination during a 100-m breaststroke swim

The purpose of this study was to compare arm–leg coordination and kinematics during 100 m breaststroke in 26 (8 female; 18 male) specialist breaststroke swimmers. Laps were recorded using three 50-Hz underwater cameras. Heart rate and blood lactate were measured pre- and post-swim. Arm–leg coordination was defined using coordination phases describing continuity between recovery and propulsive phases of upper and lower limbs: coordination phase 1 (time between end of leg kick and start of the arm pull phases); and coordination phase 2 (time between end of arm pull and start of leg kick phases). Duration of stroke phases, coordination phases, swim velocity, stroke length (SL), stroke rate (SR) and stroke index (SI) were analysed during the last three strokes of each lap that were unaffected by turning or finishing. Significant changes in velocity, SI and SL (P < 0.05) were found between laps. Both sexes showed significant increase (P < 0.05) in heart rate and blood lactate pre- to post-swim. Males had significantly (P < 0.01) faster swim velocities resulting from longer SLs (P = 0.016) with no difference in SR (P = 0.064). Sex differences in kinematic parameters can be explained by anthropometric differences providing males with increased propelling efficiency.     

Age and sex influences on running mechanics and coordination variability

The purpose of this study was to examine the impact of age on running mechanics separately for male and female runners and to quantify sex differences in running mechanics and coordination variability for older runners. Kinematics and kinetics were captured for 20 younger (10 male) and 20 older (10 male) adults running overground at 3.5 m · s^?1. A modified vector coding technique was used to calculate segment coordination variability. Lower extremity joint angles, moments and segment coordination variability were compared between age and sex groups. Significant sex–age interaction effects were found for heel-strike hip flexion and ankle in/eversion angles and peak ankle dorsiflexion angle. In older adults, mid-stance knee flexion angle, ankle inversion and abduction moments and hip abduction and external rotation moments differed by sex. Older compared with younger females had reduced coordination variability in the thigh–shank transverse plane couple but greater coordination variability for the shank rotation–foot eversion couple in early stance. These results suggest there may be a non-equivalent aging process in the movement mechanics for males and females. The age and sex differences in running mechanics and coordination variability highlight the need for sex-based analyses for future studies examining injury risk with age.     

审视国家助学贷款政策

随着高等教育的发展,高校贫困生问题日益突出,高等教育的资金需求越来越大,国家助学贷款政策应运而生.理论上,国家助学贷款政策是政府为了促进教育事业的发展、为了高等教育的公平、为了社会的公正而做出的实践性决策,对个人和组织的行为产生影响;其本质是学生、高校、社会之间的利益协调和平衡.就实践而言,学生、学校、政府、银行四方都不同程度地成为国家助学贷款政策的受益者.国家助学贷款工作的健康发展,既需学生、学校、银行和政府的单方努力也需要多方配合.     

交通运输与经济发展协调程度的定量评价

运用大系统的理论与方法,建立了一类反映交通运输与经济协调发展程度的综合指标———协调发展指数,并建立了定量分析模型,提出了相应的定量评价计算方法。最后,运用该方法对某市交通运输与经济的协调程度进行了实例分析。     

补充辅酶Q10及递增负荷跑台运动训练对大鼠心肌和脑线粒体电子传递链酶复合体活性的影响

目的:观察递增负荷跑台运动训练及补充CoQ10对力竭运动大鼠心肌和脑线粒体呼吸链复合体Ⅰ、Ⅱ和Ⅲ活性的影响.方法:36只健康雄性Wister大鼠随机分为安静对照组、补充CoQ10组、训练组和训练结合补充CoQ10组.差速离心提取心肌和脑线粒体;分光光度法测定线粒体呼吸链酶复合体(Ⅰ～Ⅲ)活性.结果:1)安静状态下补充CoQ10 7周,与安静对照组相比较,力竭运动后即刻心肌线粒体呼吸链CⅡ活性增强(P＜0.01),CⅠ和CⅢ活性减弱(P＜0.01);脑线粒体呼吸链CⅡ活性显著性降低(P＜0.01).2)递增负荷运动训练7周,与安静对照组相比较,力竭运动后即刻心肌线粒体呼吸链CⅠ和CⅡ活性减弱(P＜0.01)、CⅢ活性增强(P＜0.05).3)递增负荷训练结合补充CoQ10 7周,与安静对照组相比较,力竭运动后即刻心肌线粒体呼吸链CⅠ和CⅡ活性减弱(P＜0.01),脑线粒体呼吸链CⅡ活性显著性下降(P＜0.01).4)递增负荷训练结合补充CoQ10与单纯补充CoQ10组相比,力竭运动后即刻心肌线粒体呼吸链CⅡ活性减弱(P＜0.01)、CⅢ活性增强(P＜0.01);脑线粒体呼吸链CⅡ活性显著性下降(P＜0.01).5)递增负荷训练结合补充CoQ10与单纯运动训练组相比,力竭运动后即刻心肌线粒体呼吸链CⅡ和CⅢ活性减弱(P＜0.01);脑线粒体呼吸链CⅡ活性显著性下降(P＜0.01).结论:外源性补充CoQ10对大鼠体重增长无负面影响,运动训练可以降低大鼠体重增长幅度.单纯补充CoQ10可增强力竭运动后即刻大鼠心肌线粒体呼吸链CⅡ活性;降低脑线粒体呼吸链CⅡ活性;对力竭运动时间无影响.递增负荷训练可增强力竭运动后即刻大鼠心肌线粒体呼吸链CⅢ活性;对脑线粒体呼吸链CⅠ、CⅡ和CⅢ活性无明显影响;运动能力得到提高.递增负荷训练结合补充CoQ10可维持力竭运动后即刻大鼠心肌线粒体呼吸链CⅢ活性不降低;脑线粒体呼吸链CⅡ活性显著性下降、CⅠ和CⅢ活性无显著性变化;运动能力得到提高;运动训练与补充CoQ10对改善心肌和脑线粒体呼吸链cⅠ、CⅡ和CⅢ活性及运动能力方面无协同作用.训练组及训练结合补充CoQ10组大鼠力竭运动时间的延长可能还与体重增长较慢及其他机制有关.     

动作协调与"爆发力"表现田径跳跃动作协调能力测量与评价方法研究

通过专家访谈与问卷调查,确定了6组12项动作指标作为协调能力测试行为样本。运用生物力学方法与人体运动的动力学方法,以相同动作冗余自由度的控制与不控制作为刺激变量,以动作爆发力表现水平的差值为因变量,通过对两组不同水平被试测验成绩的比较,对跳跃专项动作协调能力进行了定性与定量评价。     

7-10岁男子少年武术运动员动作协调能力发展特征研究

文章运用问卷调查法、实验法、专家评定法、数据统计法,对设计的五项测试动作协调能力指标,在120名7-10岁少年武术运动员和普通学生中进行对比实验分析,研究结果表明:7-10岁少年武术运动员组协调能力发展水平整体高于普通学生组;7-9岁年龄段少年儿童动作协调能力增长速度比较快,9-10岁年龄段是协调能力发展平缓期;7-8岁年龄段是武术运动员听觉肢体协调能力和上下肢体协调能力的突增期,平均增长率在30%以上。     

协调训练对少儿游泳运动员运动能力的影响

协调能力是指在进行身体运动过程中,调节与综合身体各个部分动作的能力,通过对少儿游泳运动员的协调训练的实验研究,有效地运用协调训练手段对提高少儿游泳的运动成绩有极大的帮助。