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1.
BackgroundAthletes tend to have better visuo-motor performance than do sedentary individuals. However, several basic visual-function and perceptual parameters remain unexplored to date. In this study, we investigated whether differences exist in visual function, performance, and processing between basketball players and individuals without a sport-involvement background.MethodsA total of 33 healthy men with no visual impairment or pathology were divided into 2 groups, depending on the involvement in sport (semi-professional basketball players and sedentary individuals). We tested their baseline heart-rate variability in the resting position apart from subjective questionnaires to determine their physical fitness level, and we checked their visual function, performance, and processing through an extended battery of optometric tests.ResultsThe 2 groups differed in resting heart-rate variability parameters (p < 0.001), confirming their dissimilarities in regular time practising sports per week. The basketball players showed a closer breakpoint and recovery nearpoint of convergence, a higher fusional-vergence rate, better discriminability halos, and better eye–hand coordination (all p values < 0.05).ConclusionThese results show evidence that athletes, basketball players in this case, exhibit better performance in several visual abilities in comparison to a group of individuals without sporting backgrounds, suggesting an improvement due to the systematic involvement of those skills during basketball practice.  相似文献   
2.
BackgroundHealth-related fitness knowledge (HRFK) has been an essential concept for many health and physical education programs. There has been limited understanding and longitudinal investigation on HRFK growth. This longitudinal study examined HRFK growth and its individual- and school-level correlates in middle school years under 1 curriculum condition: Five for Life.MethodsParticipants were 12,044 students from 47 middle schools. Data were collected at both individual/participant and school/institution levels. Individual-level variables included gender, grade, and HRFK test scores. School-level variables included percentage of students receiving free and reduced meals (FARM), student-to-faculty ratio for physical education, and school academic performance (SAP). We used hierarchical linear modeling to examine HRFK 3-year growth in relation to individual- and school-level correlates.ResultsThe average HRFK score at 6th grade for females was 42.81% ± 1.32%. The predicted HRFK growth was 17.06% ± 1.02% per year, holding other factors constant. A 1-standard deviation increase in FARM correlated with a 14.68%-point decrease in predicted test score (p = 0.02). A 1-standard deviation increase in SAP was associated with an 11.90%-point increase in HRFK score. Males had a significantly lower growth rate than females during the middle school years (0.78%/year, p = 0.02).ConclusionThe result showed that both individual- and school-level variables such as gender, FARM, and SAP influenced HRFK growth. Educators should heed gender differences in growth curves and recognize the correlates of school-level variables.  相似文献   
3.
采用文献资料法、实地考察法、数理统计法和对比分析法,对我国奥运选手和世界优秀选手的一号木数据进行分析。发现,在实地考察的球洞中,世界优秀选手全四轮均使用一号木开球,而我国男子选手则是一号木、三号木交替开球,可能是由于对自身一号木开球技术不够自信;我国男子选手的一号木平均开球距离、上球道率较世界优秀选手均差距较大;我国女子选手的一号木平均开球距离与世界优秀选手较为接近,但上球道率有待提高。建议,男子选手加强开球距离和上球道率的训练,女子选手加强上球道率的训练;冯珊珊进一步提升开球距离;在比赛前要对场地进行多次熟悉,找到合适的开球策略。  相似文献   
4.
采用文献研究法、定性分析法和定量分析法,对目前国内外部分医院科研现状进行分析,总结医院的科研现状和发展规律,分析医院科研对医院的贡献,为提高医院科研水平提供参考依据。结果表明:医院科研给医院带来的贡献包括科研产出和科研声誉;医院开展科研,在SCI发文量和专利获得量上,给医院带来了巨大的贡献;同时,良好的科研会提高医院在医院排行榜上的位置,提高医院声誉。  相似文献   
5.
马克思的两部类再生产模型中的各部类和全社会最高与最低积累率问题,是尚未获得完满解决的难点问题。本文运用单调函数的性质和求函数最大、最小值方法,通过解析,给出了静态意义下的各部类和全社会最高及最低积累率与两个部类结构参数的函数关系式。并且引用和借鉴《资本论》中的举例,对给出的函数关系式做了算例验证。  相似文献   
6.
高校评教是高校教育教学管理中的重要一环。文章针对目前已有的评教系统数据源单一、数据使用不充分、教师反馈不及时、师生互动性欠佳、学生评教积极性不高等现状,提出了一个高校评教系统新框架,以评教结果的使用范围为目的,反推出评教数据来源应具备多次性和多样性。每学期多次评教,实现教师与学生的互动,促进学生评教积极性,促进教师及时改进教学方法。评教人员除了学生之外,还应包括督导专家和往届生。  相似文献   
7.
国有商业银行如何应对利率市场化改革的风险   总被引:1,自引:0,他引:1  
利率市场化改革给国有商业银行的经营带来更大的风险,如:竞争风险、信用风险、利率风险、流动性风险等。如何趋利避害,应对风险,笔者认为从4个方面入手:产权制度改革;经营观念的转变;业务上由传统业务向中间业务、表外业务转变,由分业经营向混业经营转变;风险的全面管理。  相似文献   
8.
Frame skipping in low bit video coding could significantly reduce the visual quality of reconstructed video. At the same time, if the complexity of the video sequence remains high for a long period, then driving up the long term average bit rate, the only resort of MPEG-4 Q2 rate control algorithm results in using a high quantization scale, which shows a poor visual quality of the reconstructed video. This paper analyzes the main causes of frame skipping in current MPEG-4 frame rate control scheme, and presents a new rate control algorithm based on the quadratic R-D model over a CBR channel. Key features of the present work are. 1) the bits allocated to each P-frame or B-frame are in proportion to its distance from the end of this GOP, i.e. more bits are allocated to the frames that are nearer to their reference Ⅰ -frame: 2) the target buffer level is changeable in the GOP, at the end of each GOP( five P-frames or B-frames), the target buffer level is linearly reduced from 1/2 to 1/4 of buffer size, to other frames, the target buffer level is set to 1/2 of buffer size: 3 ) a selective and judicious use of the reduced resolution mode, in addition to a modulation of the quantization scale parameter, is to control the average long term bit rate. Experimental results with different video sequences of varied complexity, encoded at low bit rates show better efficacy of the proposed algorithm than MPEG-4 Q2 rate control scheme, and the experimental results also show that the improved algorithm has significantly reduced the number of frame skipping, increased the overall PSNR, and improved the perceptual quality.  相似文献   
9.
应用索洛余值法对福建全省经济增长及科技进步贡献率进行测算,计算出科技进步和其他要素对经济增长的贡献份额,并对各地市的数据进行横向比较,得出福建省各地市科技进步的差距。  相似文献   
10.
Assessing a student's acquisition rates (ARs) is a reliable way to determine how many new words should be taught in one lesson without reducing retention. Exceeding a student's AR can result in frustration and problem behaviors. The purpose of this study was to examine the effect of AR on the off‐task behavior of kindergarten students while participating in a commonly used sight‐word instruction video. Participants included 39 kindergarten students whose ARs were assessed before showing the sight‐word video. Behavior was measured as on‐ and off‐task using momentary time‐sampling with 10‐s intervals. Results indicated that students' time off task increased after exceeding their ARs, with a noticeable immediate increase. The implications and limitations of these results are discussed.  相似文献   
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