Athens 2004: the pollution climate and athletic performance

Athens sits in a basin approximately 450 km2 in area, surrounded by mountains and open sea. Anthropogenic emissions in conjunction with the topographical and meteorological conditions can result in high air pollution within the city. The pollutants of concern for athletes competing in Athens 2004 appear to be nitrogen dioxide (NO2), ozone and particulate (PM10) pollution. Exposure to elevated ozone concentrations has been reported to give rise to symptoms that include cough, chest pain, difficulty in breathing, headache, eye irritation and a decrease in forced expiratory volume in one second. All of these effects are likely to impact upon performance, and several studies of cyclists suggest this to be the case. In contrast, the impact of ambient concentrations of NO2 appears to be negligible on normal activities, but at high exercise intensities the impact remains unclear. The use of currently available information and models to predict the effect of ozone and other pollutants on elite athletes is problematical, since such models are based upon significantly lower ventilation rates than those achieved by some elite athletes. In addition, it is already known that the response to ozone can vary somewhat between individuals. Since the individuals who will be competing in Athens are physiologically very different to the participants in most published studies, it is difficult to predict individual responses. There is some evidence to indicate that adaptation to the adverse health and performance effects of ozone can occur, so that performance is partially recovered on re-exposure. The adaptation is not seen in all studies and appears to be dependent on several factors, including the initial sensitivity of the individual to ozone. Antioxidant supplementation has also been shown in some studies to partially ameliorate the adverse effects of ozone by counteracting the oxidative stress mechanism associated with this pollutant. Whether this transfers to performance enhancement per se remains unclear at present. Additional research is required to gain a sound understanding of the effects of a complex mixed air pollution exposure on the pulmonary function and performance of athletes exercising at high work intensities.     

我国学生体质健康的现状、成因及对策研究

我国对学生体质健康现状的调查表明：我国学生存在体质健康持续下降的危机。据此，文章从家庭、学校应试教育和传统社会文化等方面探讨了导致学生体质健康持续下降的成因，并提出了提高学生体质健康水平的具体对策。     

Can constrained relevance feedback and display strategies help users retrieve items on mobile devices?

Searching online information resources using mobile devices is affected by small screens which can display only a fraction of ranked search results. In this paper we investigate whether the search effort can be reduced by means of a simple user feedback: for a screenful of search results the user is encouraged to indicate a single most relevant document. In our approach we exploit the fact that, for small display sizes and limited user actions, we can construct a user decision tree representing all possible outcomes of the user interaction with the system. Examining the trees we can compute an upper limit on relevance feedback performance. In this study we consider three standard feedback algorithms: Rocchio, Robertson/Sparck-Jones (RSJ) and a Bayesian algorithm. We evaluate them in conjunction with two strategies for presenting search results: a document ranking that attempts to maximize information gain from the user’s choices and the top-D ranked documents. Experimental results indicate that for RSJ feedback which involves an explicit feature selection policy, the greedy top-D display is more appropriate. For the other two algorithms, the exploratory display that maximizes information gain produces better results. We conducted a user study to compare the performance of the relevance feedback methods with real users and compare the results with the findings from the tree analysis. This comparison between the simulations and real user behaviour indicates that the Bayesian algorithm, coupled with the sampled display, is the most effective. Extended version of “Evaluating Relevance Feedback Algorithms for Searching on Small Displays, ” Vishwa Vinay, Ingemar J. Cox, Natasa Milic-Frayling, Ken Wood published in the proceedings of ECIR 2005, David E. Losada, Juan M. Fernández-Luna (Eds.), Springer 2005, ISBN 3-540-25295-9     

2011-2012CBA总决赛双方技术应用特征因子分析——基于小样本SAS软件iml(矩阵运算)因子分析

通过文献资料法、录像观察法、小样本SAS软件因子分析法,对2011-2012CBA总决赛双方五场比赛中技术应用的指标进行了特征因子分析,结果为:篮球比赛中技术因素发挥是对立统一、相互博弈的辩证关系;通过纵、横向比较两队总决赛中每场次综合因子得分,制胜因子与遏制因子博弈的贡献统计,对双方比赛的竞技实力进行了讨论,旨在为今后的篮球竞赛与技术训练提供有价值的参考。     

Sport and Friendship

My aim in this paper is to make the case for encouraging friendship in sport. First, I argue that sport is especially conducive to friendship. Second, I argue that since friendship is life‐enhancing then to participate in sport and not to have made friends is to have failed to take a life‐enhancing opportunity. Third, I argue that there are sporting benefits to be had from sporting friendships. Finally, I say something about the role of friendship in sport achieving its broad political aim of helping ‘to build a better and more peaceful world’.     

Utilization of online educational resources in teaching: A moderated mediation perspective

The study builds on a newly modified Technology Acceptance Model (TAM) to substantiate the motivation and operation of teachers’ utilization of online learning resources. A ‘Comprehensiveness’ construct is proposed in the modified TAM to reflect the breadth and depth of rich online knowledge. This new construct serves as the mediator between ‘Usefulness’ and ‘Behavioral Intention’ in the new TAM structure. In addition, the ‘Ease of Use’ factor in conventional TAM is proposed to moderate the mediation in the modified TAM. Survey data are collected from 301 teachers undertaking certified training in Macau and Structural Equation Model (SEM) technique is used to assess the model. Moderated mediation is evaluated using both multi-group bootstrapping method and moderated path analysis method. Both methods verify the presence of moderated mediation with partial mediation in high Ease of Use values and full mediation in low Ease of Use values. Theoretical implication of the current study extends the coverage of TAM applications and academic implication suggests the strengthening in teachers’ professional development and government sponsorship in building repositories of online resources.     

āwhina: a programme for Māori and Pacific tertiary science graduate and postgraduate success

In New Zealand, Māori (indigenous New Zealanders) and Pacific students tend not to attain the same levels of educational success as Pākehā (New Zealanders of European descent). Addressing this problem is a particular challenge in the sciences. The kaupapa (values-base) of Te Rōpū Āwhina (Āwhina) is to produce Māori and Pacific professionals to contribute to Māori and Pacific development and leadership through the creation of an inclusive off- and on-campus whānau (extended family) environment where high expectations, aspirations and achievement, collective success, and reciprocity are normalised. This paper reviews theories and practices of recruitment and retention relevant to Māori and Pacific students at tertiary level, presents the rationale for Āwhina in the Faculties of Science and Architecture and Design at Victoria University of Wellington, and assesses the impact of the whānau. Based on analyses of quantitative measures of student achievement, and biennial surveys of student responses from the first 6 years of Āwhina, it is suggested that the results are consistent with improving Māori and Pacific graduate and postgraduate achievement and retention. Potential implications for efforts to reduce disparities in tertiary education in New Zealand and elsewhere are summarised.