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51.
The basic anatomy of an experimental design is used as an expository introduction to the examination of several repeated measures experiments described in recent pages of this and other journals. This examination reveals problematic issues concerning some common design and analysis features of such experimental designs. In particular, the hierarchical structures and/or presence of time trends is highlighted. These issues are discussed in an attempt to assist researchers to recognize such problems, to avoid the associated difficulties in the future, and to exploit the advantages of sound design with appropriate, efficient and informative analysis. While alternate reanalyses of the data of these experiments might reveal the conclusions to be unaffected by such issues, researchers should still be cautious. In retrospect, such occurrences should be seen as fortuitous, not as justification for inefficient or less informative analyses. More importantly, such reanalyses could reveal more enlightening information, and I argue that if a design permits such information to be discovered, then it behoves researchers to perform such analyses and to make such discoveries.  相似文献   
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Lack of benefit of warm up on prolonged intermittent-sprint performance has been proposed to be due to use of a pacing strategy by participants. To investigate this, twelve participants performed four cycle trials that consisted of either prolonged intermittent-sprint performance (80 min) or single-sprint performance (4 s), with or without a warm up. The first-sprint of intermittent-sprint performance was also assessed. No interaction effects (P > 0.05) were found between trials for intermittent-sprint performance for total work (J · kg(-1)), or percentage work and power decrement. Work done during the first-sprint of intermittent-sprint performance (no warm up) was less (P < 0.001) than the first-sprint of intermittent-sprint performance (warm up; effect size (ES) = 0.59) and both single-sprint trials (warm up and no warm up; ES = 0.91, 0.75, respectively). Peak power (W · kg(-1)) for single-sprint (warm up) was greater (P < 0.05) than single-sprint (no warm up), and the first-sprint of intermittent-sprint performance (warm up and no warm up). Warm up improved single-sprint performance and the first sprint of intermittent-sprint performance. Use of a pacing strategy probably resulted in similar intermittent-sprint performance between trials. These results suggest that team-sport players should perform a warm up at the start of a game or before substitution during a game.  相似文献   
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PurposeThe purpose of this study was to compare established methods with newly-developed methods for estimating the total energy expenditure (TEE).MethodsThe study subjects comprised 46 individuals, including 16 middle-aged men (mean age 51.4 years), 14 middle-aged women (mean age 49.9 years) and 16 young women (mean age 19.1 years). The TEE was estimated from 24-h heart rate (HR) data using newly-developed software (MoveSense HRAnalyzer 2011a, RC1, Suunto Oy, Vantaa, Finland), and was compared against the TEE determined using doubly labeled water (DLW). Agreement between the two methods was analyzed using Bland and Altman plots.ResultsThe HR method yielded similar TEE values as the DLW method at the group level, with an average of 8.6 kcal/day in the difference in the mean, but with large individual variations. Forty-four (96%) out of 46 subjects fell within ±2SD of the mean difference in TEE comparisons, and there was no tendency towards under- or over-estimation.ConclusionOur results indicate that the current software using HR analysis for the estimation of daily TEE needs further development for use with free-living individuals.  相似文献   
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OBJECTIVE: The aim of this study was to examine the trajectory of cases through four systems: child protection, law enforcement, the dependency courts, and the criminal courts. METHOD: This study focused on a county selected from a 41-county telephone survey conducted for the National Incidence Study of Child Abuse and Neglect (NIS-3). For this analysis prospective samples were drawn from law enforcement (n=225) and the county child protection (CPS) agency (n=225) and followed through in-depth case tracking across all agencies and through both the dependency and criminal court systems. RESULTS: The percentage of CPS cases opened in dependency court was similar to prior studies (29%), but the acceptance and prosecution rates were much higher--92% of the cases referred from CPS, including many cases of physical abuse. Compared to referrals from CPS to law enforcement (93%), few cases were referred from law enforcement to CPS (17%). Anecdotally, case referral patterns appeared to be influenced by communication patterns and mutual positive regard, regardless of the collaborative protocols in place. One of the most instructive findings was the degree of difficulty in tracking cases across organizations and the types of obstacles that impeded success. Disorganization was not an issue, rather internal structures set up to facilitate intra-organizational processing were the same structures that actually impeded cross-organizational case finding. CONCLUSIONS: It is not sufficient to rely on the existence of multi-disciplinary teams or Child Advocacy Centers to ensure collaboration. More attention to daily tasks and activities as well as the nature and quality of communication is warranted. On the technical side, use of common case identifiers on cases that are cross-referred is strongly recommended. Future studies should broaden the scope of inquiry to include the consequences of all case trajectories, rather than solely focusing on the justice system.  相似文献   
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Through reflection on the First International iPED Conference 2006, and its overarching theme of ‘Pedagogical Research and Academic Identities’, this paper considers the achievement of the wider aims of the conference, which were to facilitate dialogue between researchers in order to explore the conference themes collaboratively, and to provide networking opportunities which would enable participants to build alliances. The abstracts for all papers mentioned are available via the conference website www.coventry.ac.uk/iped2006.  相似文献   
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Online piracy of copyrighted digital music has become rampant as Internet bandwidth and digital compression technologies have advanced. The music industry has suffered significant financial losses and has responded with lawsuits, although online music piracy remains prevalent. This article developed a research model to study the determinants of individual intentions to commit online music piracy. The model was derived from the theories of planned behavior and deterrence. A survey questionnaire of 216 respondents was used to test the model. Consistent with the theory of planned behavior, the results showed that attitude toward online music piracy, subjective norms, and perceived behavioral control are significant antecedent factors of intention to commit online music piracy. Concerning deterrence theory, the results suggest that the effect of perceived punishment severity on attitude was highly significant for females, and the effect of perceived certainty of punishment on attitude was not significant for males or females.  相似文献   
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