蜂胶对运动训练小鼠抗疲劳能力影响的研究

目的:通过给训练小鼠灌服蜂胶,观察蜂胶对训练小鼠红细胞形态、血浆及心肌自由基代谢的影响,为蜂胶在运动领域的应用提供实验依据。方法:健康KM小鼠30只,随机分为安静组、训练组、训练+蜂胶组。三组小鼠每日上午均灌胃:安静组、训练组灌服蒸馏水;训练+蜂胶组按45mg/kg体重灌服蜂胶。训练组和训练+蜂胶组进行四周递增强度的游泳训练。结果:①4周游泳训练组小鼠与安静组相比,红细胞畸形率、心肌、血浆MDA含量显著增高,心肌、血浆SOD活性、红细胞Na+-K+-ATP酶活性显著降低;②训练+蜂胶组小鼠红细胞畸形率、心肌、血浆MDA含量显著低于训练组,心肌、血浆SOD活性、红细胞Na+-K+-ATP酶、GSH-Px、Ca2+-ATP酶活性显著高于训练组。结论:①经过4周游泳训练后,小鼠机体脂质过氧化程度加重,运动能力下降。②在4周的游泳训练过程中,给小鼠灌服蜂胶,可以明显改善小鼠运动后的抗疲劳能力。     

Programming Time as a Function of Movement Constraint

Abstract

Although the benefits of exercise are well documented, an international problem of physical inactivity exists. More research, especially theory based, has been recommended. One promising approach for studying exercise behavior is that proposed in the Transtheoretical Model (TTM) of behavior change. This model, however, has received minimal cross-cultural attention and, relative to the current study, measurement instruments have only recently been translated into the Finnish language. The purpose of this study was to assess American and Finnish college students' exercise behaviors on the basis of TTM. Participants were American (n = 169) and Finnish (n = 168) college students who completed language-specific measures of exercise behavior, stage of change, processes of change, decisional balance, self-efficacy, and temptation. The only cultural difference observed was that the American participants rated themselves higher on barrier self-efficacy relative to the Finnish participants. Regardless of nationality or gender, participants classified by their stage of change differed on all the core constructs assessed. These results generally support the utility of TTM for understanding American and Finnish college students' exercise behavior.     

The differential effects of PNF versus passive stretch conditioning on neuromuscular performance

Abstract

The effects of flexibility conditioning on neuromuscular and sensorimotor performance were assessed near to full knee extension (25°). Eighteen males who were randomly assigned into two groups underwent eight weeks (three-times per week) of flexibility conditioning (hip region/knee flexor musculature; dominant limb) involving either proprioceptive neuromuscular facilitation (PNF) (n=9) or passive stretching (PASS) (n=9). Both modes of flexibility conditioning are popular within contemporary exercise and clinical settings and have demonstrated efficacy in improving range of motion. The contralateral limb and a prior ‘no exercise’ condition were used as controls. The PNF and PASS modes of conditioning improved passive hip flexibility to a similar extent (mean 19.3% vs. baseline, intervention limb, p<0.01) but did not alter knee flexor strength (overall mean 309.6±81 N) or sensorimotor performance (force and positional errors: 2.3±8.2% and 0.48±7.1%). Voluntary and magnetically evoked electromechanical delays (EMD_V and EMD_E, respectively) were increased but to a greater extent following PASS compared to PNF (PASS: 10.8% and 16.9% lengthening of EMD_V and EMD_E, respectively vs. PNF: 3.2% and 6.2%, p<0.01).The attenuated change to electromechanical delay (EMD) performance during PNF conditioning suggests a preserved capability for rapid muscle activation, which is important in the maintenance of dynamic joint stability. That PNF was also equally efficacious in flexibility conditioning would suggest that this mode of flexibility training should be used over passive to help preserve dynamic joint stability capabilities at this extended and vulnerable joint position.     

Modelling the decision to volunteer in organised sports

Using a heterodox economic approach, the purpose of this paper is twofold: to analyse the determinants of (1) volunteering in organised sports, and (2) time committed to that volunteering. By means of regression analysis of secondary data from a nation-wide volunteer survey with two waves (2004: n = 15,000; 2009: n = 20,005), it was established that human capital, female gender and the motive of shaping society had a negative influence on the decision to volunteer while the number of engagements in other volunteering had a positive effect. Time committed to volunteering was determined by male gender, having children, meeting people, club membership, shaping society and number of voluntary engagements. The volunteer workforce is thus very heterogeneous; however, sport club managers should recruit volunteers in particular amongst existing members.     

2015年第二届世界休闲运动会的规划和设想--世界休闲组织主席德雷克?卡塞和秘书长克里斯托夫?爱丁顿访谈

在2012年意大利罗米尼举行的世界休闲组织理事会上,青岛市成功地获得了举办2015年第二届世界休闲运动会的主办权,笔者与世界休闲组织主席德雷克?卡塞先生和世界休闲组织秘书长克里斯托夫?爱丁顿教授,就2015年第二届世界休闲运动会的基本理念、主要目标、项目设置、举办规模、对城市的发展影响和居民生活质量的提高等问题进行访谈,对这种全新运动会发展模式给出了具体规划和设想。     

基于模糊双准则规划的高校图书馆图书采购资金分配模型

通过基于模糊双准则规划建立高校图书采访资金分配模型,首先运用三角模糊数方法从历年图书流通数据确定图书年度流通率准则,再根据图书年度流通率和科研教学准则的模糊数量指标作出图书采购资金分配决策。
     

Better Together: Responsive Community Programming at the U-M Library

In the past seven years, the University of Michigan Library's programming model has evolved to be responsive and reflective of staffing areas of interest and expertise. Our team-based, iterative model enables us to develop responsive exhibits, workshops, experiences, and events in our community. This article explores our experiences in developing this model through the lens of some of our collaborations with the Ann Arbor District Library (AADL). Our approach to programming opportunities builds on learning by doing, building deeper, mutually beneficial relationships with other organizations, and continually making sure we are truly developing programming with our audience (our community) in mind. While public and academic libraries often develop distinct sets of services, collections, and expertise to serve their respective communities, successful collaborations can yield interesting opportunities for more effective engagement and programming. Our relationship with AADL has helped us to identify and better understand how we can connect our teaching and research missions with the interests and needs of the broader community in which we are situated.     

面向技术演化分析的多主路径方法研究

[目的/意义]基于当前技术演化分析方法的发展现状,提出一种能够在微观层次上突出既定领域中主要技术发展脉络的多主路径方法。[方法/过程]将专利文本挖掘和动态规划方法应用于专利引文网络,以路径上所有专利对的语义相似度总和最优作为启发策略进行路径搜索,以获取若干能够分别聚焦于特定主题的主路径,供研究者总览既定技术领域中主要技术主题的发展脉络及其相互关系。[结果/结论]实证结果表明,将该方法应用于硬盘驱动器磁头领域,可以有效抽取其中主要技术主题的演化轨迹。     

考虑不确定性的电动汽车动力电池逆向物流网络设计

考虑到电动汽车动力电池回收量、回收技术水平等参数的不确定性,以逆向物流网络总利润最高和环境影响最小为目标,建立多目标模糊规划模型,进行电动汽车动力电池逆向物流网络设计。利用基于可信性测度的模糊求解方法处理模型中的模糊参数。引入决策者偏好系数,采用加权理想点法将多目标模型转化为单目标模型进行求解,得到考虑不确定性的逆向物流网络设施的选址、数量以及设施间的废旧动力电池流量分配方案。通过数值算例验证模型和算法的可行性和有效性。对回收量、回收技术水平和决策者偏好系数进行灵敏度分析,结果表明:随着回收量的增加,逆向物流网络利润增加;回收技术水平的提升和决策者选择合适的偏好系数可以提高逆向物流网络的经济效益和环境效益。     

考虑碳排放成本的长江铁矿石运输研究

为降低钢铁企业采购和运输铁矿石的综合成本,考虑船型、航速和碳排放等因素,建立长江铁矿石运输的混合整数非线性规划模型。将模型中的非线性项转化为线性项,运用CPLEX求解器求解。针对CPLEX求解中大型规模算例的局限性,引入标准粒子群优化（particle swarm optimization, PSO）算法提高求解精度。针对标准PSO算法容易陷入局部最优的问题,提出一种基于自适应策略的改进PSO算法,动态调整惯性权重,提高算法的收敛性和全局寻优能力。通过数值实验发现,改进后的算法在全局寻优能力和收敛能力上有一定的提高。