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Ashley G. B. Willmott Mark Hayes Kirsty A. M. Waldock Rebecca L. Relf Emily R. Watkins Carl A. James 《Journal of sports sciences》2017,35(22):2249-2256
Multistage, ultra-endurance events in hot, humid conditions necessitate thermal adaptation, often achieved through short term heat acclimation (STHA), to improve performance by reducing thermoregulatory strain and perceptions of heat stress. This study investigated the physiological, perceptual and immunological responses to STHA prior to the Marathon des Sables. Eight athletes (age 42 ± 4 years and body mass 81.9 ± 15.0 kg) completed 4 days of controlled hyperthermia STHA (60 min·day?1, 45°C and 30% relative humidity). Pre, during and post sessions, physiological and perceptual measures were recorded. Immunological measures were recorded pre-post sessions 1 and 4. STHA improved thermal comfort (P = 0.02), sensation (P = 0.03) and perceived exertion (P = 0.04). A dissociated relationship between perceptual fatigue and Tre was evident after STHA, with reductions in perceived Physical (P = 0.04) and General (P = 0.04) fatigue. Exercising Tre and HR did not change (P > 0.05) however, sweat rate increased 14% (P = 0.02). No changes were found in white blood cell counts or content (P > 0.05). Four days of STHA facilitates effective perceptual adaptations, without compromising immune status prior to an ultra-endurance race in heat stress. A greater physiological strain is required to confer optimal physiological adaptations. 相似文献
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Tunable pores (TPs) have been used for resistive pulse sensing of 1 μm superparamagnetic beads, both dispersed and within a magnetic field. Upon application of this field, magnetic supraparticle structures (SPSs) were observed. Onset of aggregation was most effectively indicated by an increase in the mean event magnitude, with data collected using an automated thresholding method. Simulations enabled discrimination between resistive pulses caused by dimers and individual particles. Distinct but time-correlated peaks were often observed, suggesting that SPSs became separated in pressure-driven flow focused at the pore constriction. The distinct properties of magnetophoretic and pressure-driven transport mechanisms can explain variations in the event rate when particles move through an asymmetric pore in either direction, with or without a magnetic field applied. Use of TPs for resistive pulse sensing holds potential for efficient, versatile analysis and measurement of nano- and microparticles, while magnetic beads and particle aggregation play important roles in many prospective biosensing applications. 相似文献
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The field hockey hit is an important but poorly understood stroke. In this study, we investigated the planarity of the stickface motion during the downswing to better characterize the kinematics and to assess the suitability of planar pendulum models for simulating the hit. Thirteen experienced female field hockey players were filmed executing hits with a single approach step, and the kinematics of the centre of the stickface were measured. A method was developed for identifying how far back from impact the stickface motion was planar. Orthogonal regression was used to fit least-squares planes to the stickface path during sections of the downswing of varying length, with each section ending at impact. A section was considered planar if the root mean square residual between the stickface path and the fitted plane was less than 0.25% of the distance travelled by the stickface during that period. On average, the stickface motion was planar for the last 83 ± 12% of its downswing path, with the length of the planar section ranging from 1.85 m to 2.70 m. The suitability of a planar model for the stickface motion was supported, but further investigation of the stick and arm kinematics is warranted. 相似文献
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School Effectiveness Research: an Ideological Commitment? 总被引：1，自引：0，他引：1
Robert Willmott 《Journal of Philosophy of Education》1999,33(2):253-268
As the international momentum of the school effectiveness movement continues, its exponents remain largely impervious to criticism. This paper argues that while they may not readily align themselves with the individualistic aspects of Conservative social philosophy, their methodology necessarily secretes an atomised social ontology. The charge of ideological commitment rests on the fact that the essentially positivist epistemology employed by school effectiveness researchers presupposes an ontology of closed systems and atomistic events. Thus any notion of the structuring of life-chances is automatically ruled out of court. The reciprocity of social ontology and methodology is explored in order to account for the myopia of the school effectiveness movement. 相似文献
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Gary Willmott 《职业技术教育》2008,(6):64-68
2005年10月27日,新加坡人力资源部部长和教育部副部长正式发起了新加坡"劳动力技能资格"(Workforce Skills Qualifications,WSQ)制度.这一制度是新加坡从长远角度发展、促进和保持高技能、具有全球竞争力劳动力的最重要策略. 相似文献
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Knowledge as a valuable asset of organizations is increasingly incorporated into thinking about strategy. Studies of knowledge management (KM) suggest that executives engaged in decision making often have a slender understanding of the strategic significance of knowledge. When addressing the challenge of explicating and designing a knowledge strategy, logics of codification and personalization have been differentiated and commended. The paper draws upon evidence from four case studies to identify factors that shape the evolving contexts of knowledge strategies. It is in these contexts that the challenge of continuously reviewing and revising the mix of codifying and personalizing aspects of strategic KM is practically accomplished. The cases are analysed with reference to external competition, leadership, organizational politics, culture and technology as a basis for advancing a more dynamic framework for the analysis of knowledge strategies. 相似文献
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Objective: Effective warm-ups are attributed to several temperature-related mechanisms. Strategies during the transition phase, preceding swimming competition, have been shown to prolong temperature-related warm-up effects. The purpose of this study was to evaluate the effects of two different clothing strategies during the transition phase, on subsequent 100-m maximal swimming performance. Methods: Nine competitive swimmers (3 female, 21?±?3?yrs; 6 male 20?±?2?yrs, mean performance standard 702 FINA Points, mean 100-m seasons best time 61.54?s) completed their own 30-min individual pool warm-up, followed by 7-min changing time and a 30-min transition phase, straight into a 100-m maximal effort time-trial. During the transition phase, swimmers remained seated, either wearing warm or limited clothing. Swimmers returned 1 week later, where clothing conditions were alternated. Results: Post-transition phase skin and core temperature remained higher in the warm clothing condition compared to the limited clothing condition (Mean Core: 36.90?±?0.17°C, 36.61?±?0.15°C, P?P?P?Conclusion: Wearing warm clothing during a 30-min transition phase improved swimming performance by 0.6%, compared to limited clothing. 相似文献
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Robert Willmott 《British Journal of Educational Studies》2002,50(3):339-362
It is not uncommon in educational research and social science in general either to eschew the word truth or to put it in scare quotes in order to signify scepticism about it. After the initial wave of relativism in the philosophy of natural science, a second wave has developed in social science with the rise of postmodernism and poststructuralism. The tendency here is to relativise truth or to bracket out questions of truth. In contradistinction, this paper revindicates the metaphysical nature of truth. Truth is a transcendental precondition of educational inquiry and is best understood as a formal, regulative norm. Realism about truth enjoins a defence of the correspondence theory, which is provided here. At the same time, however, the development of realism in the social sciences has ironically followed the postmodernists in its scepticism about truth and its rejection of the correspondence theory. This paper critically appraises such recent developments, since all research is unintelligible without realism about the social world and whether our substantive knowledge-claims correspond with it. 相似文献
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Rebecca Relf Ashley Willmott Jessica Mee Oliver Gibson Arron Saunders Mark Hayes 《Journal of sports sciences》2018,36(3):348-355
There is limited and inconclusive evidence surrounding the physiological and perceptual responses to heat stress while sleep deprived, especially for females. This study aimed to quantify the effect of 24 h sleep deprivation on physiological strain and perceptual markers of heat-related illness in females. Nine females completed two 30-min heat stress tests (HST) separated by 48 h in 39°C, 41% relative humidity at a metabolic heat production of 10 W · kg?1. The non-sleep deprived HST was followed by the sleep deprivation (SDHST) trial for all participants during the follicular phase of the menstrual cycle. Physiological and perceptual measures were recorded at 5 min intervals during the HSTs. On the cessation of the HSTs, heat illness symptom index (HISI) was completed. HISI scores increased after sleep deprivation by 28 ± 16 versus 20 ± 16 (P = 0.01). Peak (39.40 ± 0.35°C vs. 39.35 ± 0.33°C) and change in rectal temperature (1.91 ± 0.21 vs. 1.93 ± 0.34°C), and whole body sweat rate (1.08 ± 0.31 vs. 1.15 ± 0.36 L · h?1) did not differ (P > 0.05) between tests. No difference was observed in peak, nor rise in: heart rate, mean skin temperature, perceived exertion or thermal sensation during the HSTs. Twenty-four hours sleep deprivation increased perceptual symptoms associated with heat-related illness; however, no thermoregulatory alterations were observed. 相似文献