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971.
ABSTRACT

Purpose: The effect of breakfast omission on evening high-intensity exercise performance has not previously been studied. Methods: In a randomised and counterbalanced cross-over design, 10 competitive rowers (2 male, 8 female; mean?±?SD: age 21?±?2 y, height 176?±?7?cm, weight 76?±?12?kg, body fat 19.7?±?6.8%) completed two trials (individualised carbohydrate-rich breakfast (BT; 831?±?67?kcal eaten before 09:00) and no-breakfast (NBT; extended overnight fast until 12:00)). Following ad libitum afternoon food intake, participants completed a 2000-m time-trial on a rowing ergometer between 16:30 and 18:00. Appetite and energy intake were measured throughout the day, whilst power output, time, heart rate, blood lactate, blood glucose and RPE were assessed during the time trial. Results: Appetite ratings were higher throughout the morning in NBT compared with BT, but there were no differences in ratings in the afternoon. Energy intake at lunch was greater NBT compared with BT (1236?±?594 vs 836?±?303?kcal, p?<?.05), which partly compensated for breakfast omission, although overall energy intake tended to be lower in NBT compared with BT (1236?±?594 vs 1589?±?225?kcal, p?=?.08). The time taken to complete the 2000-m time trial was greater in NBT compared with BT (469.2?±?43.4 vs 465.7?±?43.3?s; p?<?.05). No differences in heart rate, blood glucose and blood lactate responses were apparent, but overall RPE was higher in NBT compared with BT (17.8?±?0.9 vs 16.7?±?0.7?au, p?<?.05). Conclusion: The omission of a carbohydrate-rich breakfast impaired evening performance during a 2000-m rowing time trial. This finding has implications for optimising evening high-intensity exercise performance.  相似文献   
972.
973.
Electronic learning delivery systems discussed include satellite networks, teleconferencing, Internet/Intranet networks, desktop multimedia, electronic performance support systems (EPSS), transportable audio/video (i.e., systems relying primarily on physically transportable audio-and videotaped materials), and the electronically enhanced classroom. Selecting one of these systems can be a daunting task when all relevant issues are considered. The selection model described in this article narrows the choices to the system most likely to be instructionally, economically, and technologically appropriate. After establishing working definitions, the model suggests four stages of user activity: 1) Assessing several important overall factors, including outcomes and conditions of learning, economics, synchronicity and location, and organizational culture; 2) Rating the importance of several learning system attributes to the training project; 3) Selecting the system that most ideally supports the attributes which the user has rated as important; and finally, 4) Validating the selection by reviewing the final choice in light of first stage overall factors.  相似文献   
974.
The influence of impact sound in putting on players' perceptions of "feel" is explored in this paper. Tests were conducted to investigate the impact sound characteristics of five different ball types using two different putter types. The first test studied the impact sound of purely the ball, while the second test investigated the influence of putter construction and impact location on impact sound for the different ball types. Trends were found between sound spectra peaks in the 2 - 4 kHz range and the compression values of the balls. In addition, frequency content was more dependent on putter type and impact location than on ball construction in the 0 - 2 kHz range. The final test employed a paired comparison technique to investigate players' perceptions of sharpness and loudness of impact sound, ball speed from the clubface and ball hardness. Relationships between the subjective data and the sound characteristics of the balls were then examined. It was found that the ball the players' perceived to have the sharpest and loudest sound, to feel the hardest and to come off the clubface the quickest also had the largest calculated values of loudness and sharpness and had a spectral peak at a higher frequency than the other balls.  相似文献   
975.
The purpose of the study was to develop a valid and reliable tool for use in assessing motor skills in preschool children in field based settings. The development of the CHAMPS (Children's Activity and Movement in Preschool Study) Motor Skills Protocol (CMSP) included evidence of its reliability and validity for use in field-based environments as part of large epidemiological studies. Following pilot work, 297 children (3-5 years old) from 22 preschools were tested using the final version of the CMSP and the TGMD-2. Reliability of the CMSP and interobserver reliability were determined using intraclass correlation procedures (ICC; ANOVA). Concurrent validity was assessed using Pearson correlation coefficients to compare the CMSP to the original Test of Gross Motor Development (2(nd) Edition) (TGMD-2). Results indicated that test reliability, interobserver reliability and validity coefficients were all high, generally above R/r = 0.90. Significant age differences were found. Outcomes indicate that the CMSP is an appropriate tool for assessing motor development of 3-, 4-, and 5-year-old children in field-based settings that are consistent with large-scale trials.  相似文献   
976.
Hispanic students' awareness of cultural, linguistic, and sociopolitical issues are influenced by their experiences in schools and affect their sense of identity. An examination of student discourse between bilingual gifted and bilingual general education students in an urban middle school is presented, with particular attention given to how participating bilingual students relate to each other, peers (in general and gifted education), teachers, administrators, families, and communities, and how they perceive themselves. A discussion of the core issues that emerged, including students' reawakening to their ethnic identity, differing rationales for using native language, and observed differences in self-perceptions between the gifted and general education bilingual Hispanic students is provided, along with results and implications for future research.  相似文献   
977.
978.
Automatic summarising: The state of the art   总被引:1,自引:0,他引:1  
This paper reviews research on automatic summarising in the last decade. This work has grown, stimulated by technology and by evaluation programmes. The paper uses several frameworks to organise the review, for summarising itself, for the factors affecting summarising, for systems, and for evaluation.The review examines the evaluation strategies applied to summarising, the issues they raise, and the major programmes. It considers the input, purpose and output factors investigated in recent summarising research, and discusses the classes of strategy, extractive and non-extractive, that have been explored, illustrating the range of systems built.The conclusions drawn are that automatic summarisation has made valuable progress, with useful applications, better evaluation, and more task understanding. But summarising systems are still poorly motivated in relation to the factors affecting them, and evaluation needs taking much further to engage with the purposes summaries are intended to serve and the contexts in which they are used.  相似文献   
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