我为什么不是中国人     

竹茱 《英语沙龙》2010,(3):37-37

当人们谈论起美洲大陆时,总会说:"哥伦布是第一个发现美洲大陆的人。"如今在加拿大的学校中,老师也是这样教授学生们的。但事实果真如此吗?我们都知道,明朝年间,朱棣派郑和帅舰队下西洋,他们向西航行到了很远的地方,并在航行期间绘制了航行的海图和地图。后来,哥伦布发现新大陆时,使用的就是郑和他们当年绘制的地图。但遗憾的是,由于各种原因,国内档案中几乎没有留下能说明郑和发现美洲大陆的史料。那么,对于美洲大陆的发现是要归功于郑和还是哥伦布呢?  相似文献   

How to Get Used to University Life     

Brad Franklin 《英语沙龙》2010,(12):40-41

Liu Bin刚刚跨入了大学校门。大学里的生活自由灵活。比起高中备受约束的日子可谓天壤之别,可这没有老师“管教”的生活。Liubjn反而有点不适应了。如何安排好自己的大学生活？Brad又会有哪些建议？  相似文献   

Classroom Climate,Cardiac Vagal Tone,and Inhibitory Control: Links to Focused Attention in First Graders          下载免费PDF全文

Sara Scrimin  Gabriele Osler  Ughetta Moscardino  Lucia Mason 《Mind, Brain, and Education》2018,12(1):61-70

The present study aimed to investigate the role of classroom climate and self‐regulation in terms of cardiac vagal tone and inhibitory control in primary school students' focused attention. A combination of direct and indirect measures was used to assess classroom climate, sustained and selective attention, and inattention behaviors among 62 first graders. We also registered students' cardiac vagal tone at rest and their levels of inhibitory control in a reaction time task. A single underlying factor combining sustained and selective attention as well as (the lack of) inattention behaviors accounted for students' focused attention. A regression analysis revealed that classroom climate, cardiac vagal tone, and inhibitory control interacted to explain first graders' focused attention. In classrooms with a negative climate, high levels of inhibitory control attenuated the negative effect of low cardiac vagal tone on students' ability to remain focused during classroom activities. Implications for theory and practice are discussed.  相似文献   

The effects of resistance training volume on osteosarcopenic obesity in older women     

Paolo M. Cunha  Alex S. Ribeiro  Crisieli M. Tomeleri  Brad J. Schoenfeld  Analiza M. Silva  Mariana F. Souza 《Journal of sports sciences》2018,36(14):1564-1571

The aim of this study was to analyze the effects of resistance training (RT) performed with 1 or 3 sets per exercise on osteosarcopenic obesity (OSO) syndrome parameters in older women. Sixty-two older women (68.0 ± 4.3 years, 26.8 ± 4.4 kg/m²) participated in a 12-week RT program. Participants were randomly assigned into one of the three groups: two training groups that performed either 1 set (G1S, n = 21) or 3 sets (G3S, n = 20) 3 times weekly, or a control group (CG, n = 21). Body composition was assessed by dual X-ray absorptiometry, strength was evaluated by 1 repetition maximum testing. The G3S presented significantly higher strength changes than G1S. The changes for percentage of body fat were higher for G3S compared to G1S. There was no difference in skeletal muscle mass between G3S and G1S, however both training groups displayed greater increases in this outcome compared to CG. There was no effect for bone mineral density. The overall analysis indicated higher (P < 0.05) positive changes for G3S than G1S (composed Z-score: G3S = 0.62 ± 0.40; G1S = 0.11 ± 0.48). The results suggest that a 12-week RT period is effective to improve the risk factors of OSO, and that 3 sets induce higher improvements than a single set.  相似文献   

The mascot that wouldn’t die: a case study of fan identification and mascot loyalty     

Brad Schultz  Mary Lou Sheffer 《Sport in Society》2018,21(3):482-496

The issue of sports mascot loyalty, especially to those mascots considered offensive, was investigated through fan identification theory, and applied to the mascot controversy at a large university in the United States. Replicating a previous university survey on the mascot question, a survey of current university students (N = 3616) revealed a strong relationship between mascot loyalty and fan identification, particularly related to one’s perceptions of ‘belonging to the university sports family’, and ‘associating with sports fans’ of the university. Other important findings include age differences and the marginalization of Asian-American fans. The implications and applications of these findings were discussed.  相似文献   

Contribution of uncertainty in estimation of active drag using assisted towing method in front crawl swimming     

Pendar Hazrati  Peter James Sinclair  Wayne Spratford  René Edouard Ferdinands  Bruce Robert Mason 《Journal of sports sciences》2018,36(1):7-13

Active drag force in swimming can be calculated from a function of five different variables: swim velocity, tow velocity, belt force, power output and exponent of velocity. The accuracy of the drag force value is dependent on the accuracy of each variable, and on the contribution of each variable to drag estimation. To calculate uncertainty in drag value, first the derivatives of the active drag equation with respect to each variable were obtained. Second, these were multiplied by the uncertainty of that variable. Twelve national age and open level swimmers were recruited to complete four free swimming and five active drag trials. The uncertainties for the free and the tow swim velocities, and for the belt force, contributed approximately 5–6% and 2–3% error, respectively, in calculation of drag. The result of the uncertainty of the velocity exponent (1.8–2.6) indicated a contribution of about 6% error in active drag. The contribution of unequal power output showed that if a power changed 7.5% between conditions, it would lead to about 30% error in calculated drag. Consequently, if a swimmer did not maintain constant power output between conditions, there would be substantial errors in the calculation of active drag.  相似文献   

The validity and reliability of a novel indoor player tracking system for use within wheelchair court sports     

James Rhodes  Barry Mason  Bertrand Perrat  Martin Smith 《Journal of sports sciences》2013,31(17):1639-1647

Abstract

The aim of the current study was to investigate the validity and reliability of a radio frequency-based system for accurately tracking athlete movement within wheelchair court sports. Four wheelchair-specific tests were devised to assess the system during (i) static measurements; (ii) incremental fixed speeds; (iii) peak speeds; and (iv) multidirectional movements. During each test, three sampling frequencies (4, 8 and 16 Hz) were compared to a criterion method for distance, mean and peak speeds. Absolute static error remained between 0.19 and 0.32 m across the session. Distance values (test (ii)) showed greatest relative error in 4 Hz tags (1.3%), with significantly lower errors seen in higher frequency tags (<1.0%). Relative peak speed errors of <2.0% (test (iii)) were revealed across all sampling frequencies in relation to the criterion (4.00 ± 0.09 m · sˉ¹). Results showed 8 and 16 Hz sampling frequencies displayed the closest-to-criterion values, whilst intra-tag reliability never exceeded 2.0% coefficient of variation (% CV) during peak speed detection. Minimal relative distance errors (<0.2%) were also seen across sampling frequencies (test (iv)). To conclude, the indoor tracking system is deemed an acceptable tool for tracking wheelchair court match play using a tag frequency of 8 or 16 Hz.  相似文献   

A physiological and biomechanical comparison of over-ground,treadmill and ergometer wheelchair propulsion     

Barry Mason  John Lenton  Christof Leicht  Victoria Goosey-Tolfrey 《Journal of sports sciences》2013,31(1):78-91

Abstract

The purpose of the study was to determine which laboratory-based modality provides the most valid physiological and biomechanical representation of over-ground sports wheelchair propulsion. Fifteen able-bodied participants with previous experience of wheelchair propulsion performed a 3-minute exercise trial at three speeds (4, 6 and 8 km ? h^–1) in three testing modalities over separate sessions: (i) over-ground propulsion on a wooden sprung surface; (ii) wheelchair ergometer propulsion; (iii) treadmill propulsion at four different gradients (0%, 0.7%, 1.0% and 1,3%). A 0.7% treadmill gradient was shown to best reflect the oxygen uptake (7.3 to 9.1% coefficient of variation (CV)) and heart rate responses (4.9 to 6.4% CV) of over-ground propulsion at 4 and 6 km ? h^–1. A 1.0% treadmill gradient provided a more valid representation of oxygen uptake during over-ground propulsion at 8 km ? h^–1 (8.6% CV). Physiological demand was significantly underestimated in the 0% gradient and overestimated in the 1.3% gradient and wheelchair ergometer trials compared to over-ground trials (P<0.05). No laboratory-based modality provided a valid representation of the forces applied during OG (≥ 18.4% CV). To conclude, a 0.7% treadmill gradient is recommended to replicate over-ground wheelchair propulsion at lower speeds (4 and 6 km ? h^–1) whereas a 1.0% gradient may be more suitable at 8 km ? h^–1.  相似文献   

Validity of an upper-body-mounted accelerometer to measure peak vertical and resultant force during running and change-of-direction tasks     

Daniel W.T. Wundersitz  Kevin J. Netto  Brad Aisbett  Paul B. Gastin 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(4):403-412

This study assessed the validity of a tri-axial accelerometer worn on the upper body to estimate peak forces during running and change-of-direction tasks. Seventeen participants completed four different running and change-of-direction tasks (0°, 45°, 90°, and 180°; five trials per condition). Peak crania-caudal and resultant acceleration was converted to force and compared against peak force plate ground reaction force (GRF) in two formats (raw and smoothed). The resultant smoothed (10 Hz) and crania-caudal raw (except 180°) accelerometer values were not significantly different to resultant and vertical GRF for all running and change-of-direction tasks, respectively. Resultant accelerometer measures showed no to strong significant correlations (r = 0.00–0.76) and moderate to large measurement errors (coefficient of variation [CV] = 11.7–23.9%). Crania-caudal accelerometer measures showed small to moderate correlations (r = ? 0.26 to 0.39) and moderate to large measurement errors (CV = 15.0–20.6%). Accelerometers, within integrated micro-technology tracking devices and worn on the upper body, can provide a relative measure of peak impact force experienced during running and two change-of-direction tasks (45° and 90°) provided that resultant smoothed values are used.  相似文献   

Fragments: the implications for teachers,learners and media users/researchers of personal construal and fragmentary recollection of aural and visual messages     

John H. Mason 《Instructional Science》1988,17(3):195-218

A theory is advanced which proposes that when experience is recalled, it is recalled in fragments. The fragments are then woven logether to make a story about the experience, which is what is often called construal, or making sense. There are manifold implications of the theory: in the design of instruction which explicitly employs the theory in the ways in which students are invited to work on materials in different media; for assessment which explicitly calls upon fragment processing skills; for research into the effective use of educational media.  相似文献