Sleep restriction and degraded reaction-time performance in Figaro solo sailing races     

RÉmy Hurdiel  HANS P.A. Van Dongen  Christophe Aron  Peter McCauley  Laure Jacolot  Denis Theunynck 《Journal of sports sciences》2013,31(2):172-174

Abstract

In solo offshore sailing races like those of the Solitaire du Figaro, sleep must be obtained in multiple short bouts to maintain competitive performance and safety. Little is known about the amount of sleep restriction experienced at sea and the effects that fatigue from sleep loss have on sailors’ performance. Therefore, we assessed sleep in sailors of yachts in the Figaro 2 Beneteau class during races and compared response times on a serial simple reaction-time test before and after races. Twelve men (professional sailors) recorded their sleep and measured their response times during one of the three single-handed races of 150, 300 and 350 nautical miles (nominally 24–50 h in duration). Total estimated sleep duration at sea indicated considerable sleep insufficiency. Response times were slower after races than before. The results suggest that professional sailors incur severe sleep loss and demonstrate marked performance impairment when competing in one- to two-day solo sailing races. Competitive performance could be improved by actively managing sleep during solo offshore sailing races.  相似文献   

Information recall of younger and older skilled athletes: The role of display complexity,attentional resources and visual exposure duration     

Gershon Tenenbaum  Noa Levy‐Kolker  Michael Bar‐Eli  Robert Weinberg 《Journal of sports sciences》2013,31(6):529-534

This study was concerned with the interactive role of experience of athletic skill with other relevant environmental variables (display complexity, attentional resources, exposure time of stimuli) on perception (recall) of structured handball game situations. Nineteen experienced (older) and 19 less experienced (younger) handball players were assigned randomly either to ball‐bouncing (diverted attention) or to calm seated (focused attention) conditions. In each of the two conditions, the subjects were exposed to a total of 36 slides containing 2–3, 5–6 and 8–10 players. Eighteen slides were exposed for 0.5 s and 18 for 1.0 s. All the slides contained structured defence and offence situations. Recall scores were subjected to repeated‐measures ANOVA using attention condition and age as between‐subject factors and task complexity and exposure duration as within‐subject factors. The results showed that the recall of less experienced players deteriorated more than the recall of more experienced players following exposure to complex displays (≥ 8 players) while engaging in a secondary task (bouncing). The findings suggest that research paradigms should be applied in the field of sport which share both ecological validity and a potential to discover the cognitive substrates underlying experience and age in skilled motor performance.  相似文献   

基于EPG的蒙古语塞音、塞擦音研究     

呼和 《内蒙古大学学报(人文社会科学版)》2005,37(3):17-24

塞音、塞擦音的生理长度远远长于其声学长度。在总长度方面虽然没有明显的差别，但不送气音一般都比相应的送气音长。词首塞音和塞擦音都比相应的词尾塞音和塞擦音长。塞音和塞擦音在长度排列方面所存在的共性，可能代表它们的长度特点，而它们的因人而异的长度排列，可能显示了发音人的个性。从词首[t^h]／[t]和[t∫^h]／[t∫]的标志性舌腭接触面积变化图中可以看出，[t^h]／[t]辅音的舌位主要分布在齿区内，是舌尖上齿辅音。而[t∫^h]／[t∫]辅音的舌位主要分布在齿龈区内，是舌尖齿龈辅音。  相似文献   

Doing time in the sociology of education     

Bob Lingard  Greg Thompson 《British Journal of Sociology of Education》2017,38(1):1-12

Abstract

This article is both an editorial introduction for this special issue and a distinctive contribution in its own right. The article seeks to extend a dynamic and multiple conception of time to the sociology of education to think beyond the clock time associated with modernity and industrialisation. This need is illustrated through an account and critique of E.P. Thompson’s canonical account of clock time. The article argues that this construction of clock time implicitly frames most work in the sociology of education. The concept of ‘timespace’ offers a way to go beyond both clock time and the current ‘spatial turn’ in the sociology of education that prioritises space over time. It is shown how computerisation also ushers in a new temporality, which works simultaneously with clock time and perhaps presages the move from a disciplinary to control society. The article accepts that there are multiple and dynamic temporalities and correlatively supports a working together of historical and sociological imaginations towards a sociology of education that acknowledges and works with multiple temporalities, empirically, methodologically, theoretically and in research writing.  相似文献   

高温与持续荷载的复合作用对防水卷材拉伸性能的影响     

余春春  李铭 《丽水学院学报》2012,34(5):78-80

以防水层卷材为研究对象,对70℃条件下受持续荷载作用后Pvc防水卷材拉伸性能的变化进行了实验考察和分析。结果表明：（1）在70℃高温条件下,初始伸长率越大,持续荷载对PVC防水卷材拉伸性能的影响越大。初始伸长率为57．4％时,卷材的断裂伸长率降低超过70％,平均拉伸强度上升了71．8％。（2）在70℃高温条件下,持续时间在1～7d范围内,持续时间对PVC防水卷材的断裂伸长率和拉伸强度影响不明显。  相似文献   

An Experimental Study of Scheduling and Duration of “Tier 2” First-Grade Reading Intervention     

《Journal of research on educational effectiveness》2013,6(3):208-230

Abstract

This study compared the effects on reading outcomes of delivering supplemental, small-group intervention to first-grade students at risk for reading difficulties randomly assigned to one of three different treatment schedules: extended (4 sessions per week, 16 weeks; n = 66), concentrated (4 sessions per week, 8 weeks; n = 64), or distributed (2 sessions per week, 16 weeks; n = 62) schedules. All at-risk readers, identified through screening followed by 8 weeks of oral reading fluency (ORF) progress monitoring, received the same Tier 2 reading intervention in groups of 2 to 4 beginning in January of Grade 1. Group means were higher in word reading and ORF at the final time point relative to pretest; however, the groups did not differ significantly on any reading outcome or on rates of adequate intervention response. Of potential covariates, site, age, free lunch status, program coverage rate, and tutor were significantly related to student outcomes; however, the addition of these variables in multivariate models did not substantially change results. Rates of adequate intervention response were lower than have been reported for some first-grade interventions of longer duration.  相似文献   

Clients’ Expected Number of Counseling Sessions,Treatment Effectiveness,and Termination Status: Using Empirical Evidence to Inform Session Limit Policies     

《Journal of College Student Psychotherapy》2013,27(2):118-134

Many counseling centers have session limits to accommodate the increasing number of clients who seek treatment. The current study explored clients' expectations for the number of sessions over the course of one year at a large university counseling center. In contrast to previous research that has suggested clients want ten or fewer sessions, our results suggest that over 60% of clients wanted 20 or more sessions. Moreover, clients who expected 20 or more sessions reported therapy was less effective than clients who expected less than 20 sessions. While actual number of sessions was related to expected number of sessions, termination status appeared to be related to clinical factors and not clients' expected number of sessions. Implications for clinical practice and agency session limit policies are discussed.  相似文献   

Towards a Preliminary Understanding of the Social Organization of Public Libraries:     

《Public Library Quarterly》2013,32(3):21-38

Three public libraries were examined to assess their patterns of social interaction as determined by oral communication, with the primary aim of the research being to identify liaisons within the communications network. A subsidiary aim was to determine the 'fit' of the emergent with the formal organizational structure. It was possible to compare the structures of the organizations in two cases, and in both of these cases the emergent (informal) structure matched the formal structure quite closely. Library and Information Center managers need to attach some degree of importance to such knowledge as the informal and formal structural fit may impinge upon organizational effectiveness.  相似文献   

语篇阅读中时间信息加工的研究现状与展望     

仝宇光  范宁 《辽宁教育学院学报》2013,(5):34-37

在语篇阅读中,时间信息加工被认为是建构情境模型的认知过程,这一过程分成当前模型的建构、整合模型的建构和完整模型的建构三个前后相继的部分.时间信息的加工可分为时间转换的加工、时间持续信息的加工和时间相叠的加工三个研究领域.今后的研究应该从更加自然,更贴近现实的阅读情境中去探究时间信息加工的规律,并更加重视动词在时间信息加工中的作用.  相似文献   

12周惯性哑铃练习对轻度认知损害老年人的干预效果     

吕娇娇  黄灵燕  刘宇 《上海体育学院学报》2020,(5):63-69,80

目的观察12周惯性哑铃练习对轻度认知损害(MCI)老年人认知功能、身体活动能力、生活质量和睡眠质量的影响,并探讨认知改善与其他功能改变之间的关系。方法将45名MCI老年人随机分为干预组(n=22)和对照组(n=23)。干预组受试者进行惯性哑铃练习(3次/周,60 min/次,持续12周),对照组不进行运动干预。结果 12周后,干预组受试者阿尔茨海默病评定量表-认知部分(ADAS-Cog)总分/指令得分、蒙特利尔认知评估量表(MoCA)评分、起立行走计时(TUG)和SF-36健康调查问卷(SF-36)心理总得分均显著改善(均P<0.05)。与对照组相比,干预组受试者ADAS-Cog总分/单词回忆得分/注意力得分、简明精神量表(MMSE)评分、TUG和匹兹堡睡眠指数(PSQI)的改善程度均具有显著差异(P<0.05或P=0.05)。偏相关分析结果显示,SF-36心理总得分改变(r=-0.712)、PSQI改变(r=-0.380)与认知改善程度均呈显著负相关。结论 12周惯性哑铃练习可显著提高MCI老年人的认知功能,并对其移动能力、生活质量和睡眠质量具有积极影响,且心理和睡眠改变程度可能影响认知功能的改善效果。  相似文献