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131.
The purpose of this study was to compare the effects of two practical precooling techniques (skin cooling vs. skin + core cooling) on cycling time trial performance in warm conditions. Six trained cyclists completed one maximal graded exercise test (VO2(peak) 71.4 +/- 3.2 ml x kg(-1) x min(-1)) and four approximately 40 min laboratory cycling time trials in a heat chamber (34.3 degrees C +/- 1.1 degrees C; 41.2% +/- 3.0% rh) using a fixed-power/variable-power format. Cyclists prepared for the time trial using three techniques administered in a randomised order prior to the warm-up: (1) no cooling (control), (2) cooling jacket for 40 min (jacket) or (3) 30-min water immersion followed by a cooling jacket application for 40 min (combined). Rectal temperature prior to the time trial was 37.8 degrees C +/- 0.1 degrees C in control, similar in jacket (37.8 degrees C +/- 0.3 degrees C) and lower in combined (37.1 degrees C +/- 0.2 degrees C, P < 0.01). Compared with the control trial, time trial performance was not different for jacket precooling (-16 +/- 36 s, -0.7%; P = 0.35) but was faster for combined precooling (-42 +/- 25 s, - .8%; P = 0.009). In conclusion, a practical combined precooling strategy that involves immersion in cool water followed by the use of a cooling jacket can produce decrease in rectal temperature that persist throughout a warm-up and improve laboratory cycling time trial performance in warm conditions.  相似文献   
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The reduction of the administrative burden on businesses is an important governmental policy objective. Electronic government is presented as a promising reduction strategy in many countries. Underlying assumptions and mechanisms are hardly ever made explicit and scientific evidence of successful implementations is scarce. This paper presents an assessment of business-to-government systems in use in the Netherlands. Results show that organizational characteristics are the most influencing factors of perceived burden reduction and implementation effectiveness. Whereas perceived organizational benefits positively relate to the overall confirmation of the former system adoption decision. Surprisingly the quantitative, usage related characteristics do not present any statistical relevance. These findings help us understand existing differences in appreciation between business and governmental representatives on the successfulness of e-government projects in reducing the administrative burden on businesses. Furthermore, research results can help to enhance the effectiveness of e-government policy and measurement instruments.  相似文献   
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Abstract

Data were collected on the number of first yellow cards awarded during 857 games, over six seasons (1996 – 2002), played in the Football Association (FA) Cup. Overall, a significantly higher number of yellow cards were awarded against the away team, while a non-linear relationship between crowd size and yellow cards was observed. In general, the probability of a yellow card being awarded against the home team decreased as crowd size increased, but was attenuated for the largest crowd sizes. Crowd size may be related to the probability of the home team receiving a yellow card in two potential ways. Crowd noise may be a decision-making heuristic whereby the likelihood that an incident is a foul is increased when accompanied by crowd noise. Alternatively, referees may seek to appease the crowd and are more likely to do so as crowd size increases. The present findings have implications for the training of match officials and for coaches and players as they prepare to play away from home.  相似文献   
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This study analyzed the activity of expert table tennis players during a match, in reference to course of action theory (Theureau, 1992). Matches were videotaped, and the players' verbalizations as they viewed the tapes were collected a posteriori. The data was analyzed by (a) transcribing the players' actions and verbalizations, (b) decomposing their activity into elementary units of meaning, and (c) grouping the elementary units into larger sets. The results showed that the matches began with an inquiry into the specific features of the opponent's play. This was followed by reproducing the actions identified as effective during the inquiry. The results are discussed in relation to the role of training in expert performance.  相似文献   
135.
ObjectiveTo examine the impact of a 6-week endurance training on red blood cell (RBC) aging and deformability of healthy participants to detect possible improved hemorheological and performance-related adaptations.MethodsA total of 31 participants (17 females and 14 males) performed a 6-week moderate training protocol (three 1-h running sessions per week at 70% of maximal heart rate). Blood was sampled before and after the training. RBCs from each participant were fractioned according to density and age into 4 RBC subfractions. Subfractions were examined for changes of RBC properties, including aging distribution, RBC deformability, RBC microparticles, and phosphatidylserine concentrations. RBC and plasma nitrite levels were measured as indicators of nitric oxide metabolism.ResultsAerobic performance, peak oxygen consumption, ventilatory thresholds, velocity at the aerobic–anaerobic threshold, and lactate at exhaustion improved after training. The relative amount of both young RBCs and old RBCs increased, and the amount of the main RBC fraction decreased. Phosphatidylserine externalization and RBC-derived microparticles decreased. Overall deformability expressed as shear stress required to achieve half-maximum deformation to theoretical maximal elongation index at infinite shear stress improved in unfractioned RBCs (p < 0.001). Nitrite decreased in total (p = 0.001), young (p < 0.001), main (p < 0.001), and old (p = 0.020) aged RBCs and in plasma (p = 0.002), but not in very old RBCs.ConclusionThese results indicate that non-endurance-trained healthy participants benefit from a regular moderate running training program because performance-related parameters improve and a younger RBC population with improved RBC properties is induced, which might support oxygen supply in the microcirculation.  相似文献   
136.
This study investigated the bowling arm kinematics of 21 elite fast bowlers (mean +/- SD; age = 27.8 +/- 3.9 years) while performing in test, tour and one day international matches. Thirty-one of the 34 deliveries analysed exhibited straightening at the elbow joint (straightening min = 3 degrees, max = 22 degrees, mean +/- SD = 9 +/- 5 degrees), which by strict definition in the 2000 laws of cricket made them illegal. Five deliveries from three bowlers exhibited hyperextension of the bowling elbow (19 +/- 5 degrees). When assessed against an arbitrary threshold of 15 degrees for elbow straightening, ball speeds for deliveries above this threshold (39.5 +/- 2.0 m/s) were significantly faster (effect size = 1.4; p = 0.006) than deliveries below it (37.1 +/- 1.4 m/s). When grouped by delivery length, the bouncers and short deliveries recorded more elbow straightening (12 +/- 6.6 degrees) than the good length deliveries (9 +/- 4.4 degrees) and the full deliveries (8 +/- 5.7 degrees), although these were not statistically significant differences. The results of this study support the implementation of a tolerance threshold for assessing the legality of fast bowling actions. Further research is recommended into in-match kinematic modelling, laboratory based assessments of illegal bowling actions, perceptual aspects of bowling actions and remedial methods to reduce elbow straightening in bowling actions.  相似文献   
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OBJECTIVE: The professional literature on Munchausen by Proxy (MBP) abuse consists of more than 400 articles, chapters, and books. Most have come from a handful of English-speaking industrialized countries. Our aims were to establish the extent to which published work about MBP has emerged from outside these countries, and to determine the characteristics of any reported cases. METHOD: Numerous health care computer databases were queried, and the results supplemented by materials accumulated less formally. RESULTS: We identified 59 articles from 24 countries describing at least 122 cases in 9 different languages. Among cases in which the information was available, the mother was the sole perpetrator in 86%, the victim was aged between 3 years and 13 years in 52%, and the victim was male in 54%. The presentations of MBP appear to be similar across the world with the exception of induced apnea, which emerged as notably uncommon in this review. An extensive table presents the characteristics of each case. CONCLUSIONS: MBP clearly is not a phenomenon unique to Western or highly medicalized societies. This form of abuse is being increasingly recognized and reported throughout the world. The literature from the US, Canada, UK, Australia, and New Zealand often presupposes access to resources, such as subspecialists and social service agencies, that may be seriously constrained in other countries. The contributions of professionals elsewhere will be vital in ensuring that the efforts in English-speaking industrialized settings to develop standards of care encompass an international perspective.  相似文献   
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