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141.
To assess the effect of carbohydrate and caffeine on gross efficiency (GE), 14 cyclists (V?O2max 57.6 ± 6.3 ml.kg?1.min?1) completed 4 × 2-hour tests at a submaximal exercise intensity (60% Maximal Minute Power). Using a randomized, counter-balanced crossover design, participants consumed a standardised diet in the 3-days preceding each test and subsequently ingested either caffeine (CAF), carbohydrate (CHO), caffeine+carbohydrate (CAF+CHO) or water (W) during exercise whilst GE and plasma glucose were assessed at regular intervals (~30 mins). GE progressively decreased in the W condition but, whilst caffeine had no effect, this was significantly attenuated in both trials that involved carbohydrate feedings (W = ?1.78 ± 0.31%; CHO = ?0.70 ± 0.25%, p = 0.008; CAF+CHO = ?0.63 ± 0.27%, p = 0.023; CAF = ?1.12 ± 0.24%, p = 0.077). Blood glucose levels were significantly higher in carbohydrate ingestion conditions (CHO = 4.79 ± 0.67 mmol·L?1, p < 0.001; CAF+CHO = 5.05 ± 0.81 mmol·L?1, p < 0.001; CAF = 4.46 ± 0.75 mmol·L?1; W = 4.20 ± 0.53 mmol·L?1). Carbohydrate ingestion has a small but significant effect on exercise-induced reductions in GE, indicating that cyclists’ feeding strategy should be carefully monitored prior to and during assessment.  相似文献   
142.
The aim of this study was to assess the relationship between several commonly used aerobic and anaerobic cycle ergometer tests and performance during a treadmill cycling hill climb. Eight competitive cyclists (age 27+/-7 years; body mass 73.2+/-5.2 kg; height 177+/-6 cm; mean +/- s) completed six tests in random order: a lactate minimum test; a Wingate anaerobic power test; and two 6-km climbs at 6% and two 1-km climbs at 12% gradient performed on a motorized treadmill. The mean times and power outputs for the 6-km and 1-km climbs were 16:30+/-1:08 min: s and 330+/-17.8 W, and 4:19+/-0:27 min: s and 411+/-24.4 W, respectively. The best individual predictor of 6-km and 1-km performance times was the time for the corresponding climb at the other distance (r = 0.97). The next strongest predictor of both hill climb performances was the average power produced during the Wingate test divided by body mass. Stepwise regression analysis showed that the two variables contributing most to the prediction equation for both climbs were the Wingate average power per unit of body mass and maximal aerobic power divided by total mass (rider + bike), which together accounted for 92 and 96% of the variability in the 6-km and 1-km climbs. In conclusion, among competitive cyclists, the Wingate average power per unit of body mass was the best single predictor of simulated cycling hill climb performance at the distance and gradient used.  相似文献   
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144.
The human immunodeficiency virus (HIV), the virus that leads to acquired immunodeficiency syndrome (AIDS), has been a part of American society for over two decades. Today, HIV/AIDS touches all demographic groups, including young children. It is for this reason that child care providers need to be informed about HIV/AIDS and related policies that impact their work with young children. The purpose of this study was to examine child care providers' use of different HIV/AIDS information sources in relationship to their knowledge about HIV/AIDS and their response to common childhood behaviors and classroom situations involving an HIV-infected child. Results suggest that different types of information sources are associated with different aspects of providers' knowledge about and response to pediatric HIV/AIDS. Implications for the planning and delivery of HIV/AID training involving child care providers are discussed.  相似文献   
145.
The optimisation of undulatory underwater swimming is highly important in competitive swimming performance. Nineteen kinematic variables were identified from previous research undertaken to assess undulatory underwater swimming performance. The purpose of the present study was to determine which kinematic variables were key to the production of maximal undulatory underwater swimming velocity. Kinematic data at maximal undulatory underwater swimming velocity were collected from 17 skilled swimmers. A series of separate backward-elimination analysis of covariance models was produced with cycle frequency and cycle length as dependent variables (DVs) and participant as a fixed factor, as including cycle frequency and cycle length would explain 100% of the maximal swimming velocity variance. The covariates identified in the cycle-frequency and cycle-length models were used to form the saturated model for maximal swimming velocity. The final parsimonious model identified three covariates (maximal knee joint angular velocity, maximal ankle angular velocity and knee range of movement) as determinants of the variance in maximal swimming velocity (adjusted-r2 = 0.929). However, when participant was removed as a fixed factor there was a large reduction in explained variance (adjusted r2 = 0.397) and only maximal knee joint angular velocity continued to contribute significantly, highlighting its importance to the production of maximal swimming velocity. The reduction in explained variance suggests an emphasis on inter-individual differences in undulatory underwater swimming technique and/or anthropometry. Future research should examine the efficacy of other anthropometric, kinematic and coordination variables to better understand the production of maximal swimming velocity and consider the importance of individual undulatory underwater swimming techniques when interpreting the data.  相似文献   
146.
Conclusion The role of the librarian in dropout prevention can be negligible or integral. The resources are indeed there, but it is up to all involved to make use of these resources. This will require a broader, more involved version of the library. This is just what the school library profession wants to project!  相似文献   
147.
ABSTRACT

Candidate wellbeing is recognised as a continual challenge for doctoral programs, with government mandates requiring an institutional response. This article explores the experiences of candidates undertaking intensive writing sessions (‘Write-Ins’) and their influence on their wellbeing. Exploratory findings demonstrate opportunities for Write-In models to contribute positively to ‘Spaces of Wellbeing’. Spaces of Wellbeing theory highlights four dimensions of space that influence wellbeing: capability, security, integrative and therapeutic spaces. Findings show the Write-Ins contributed positively to wellbeing by offering space for candidates to enhance writing productivity, to work to their own pace, to connect with others, and to work flexibly.  相似文献   
148.
Autoshaping procedures with pigeons were used to assess the susceptibility of unconditioned response (UR) activity to Pavlovian relations between stimulus and reinforcer events. Foodpeck latency (a measure of UR activity) was investigated as a function of the interval between stimulus (keylight) and reinforcer (grain) presentations, and of the stimulus-reinforcer contingency, that is, the conditional probabilities of reinforcer delivery in the presence and absence of the stimulus. Four experiments indicated that food-peck latency was sensitive to both manipulations. Generally, conditions that led to higher keypeck rates were associated with shorter latencies. Thus, UR potentiation was demonstrated. However, when the bird’s location prior to grain delivery was fixed by imposing a keypeck-reinforcer contingency, UR potentiation vanished; it then reappeared when the location constraint was removed. Visual observations supported the conclusion that food-peck latency effects were mediated by approach/withdrawal tendencies generated by the stimulus-reinforcer relation. Implications of these results for expectancy theory are discussed.  相似文献   
149.
Current referral and identification procedures for students with learning disabilities (LD) have been criticized on conceptual and procedural dimensions, including difficulties in operationalizing the definition and in making eligibility decisions that are data based. Recognizing these difficulties, the Texas Education Agency appointed a task force to examine various issues associated with the identification, assessment, and programming of students with LD. Task force members recognized the need to identify classroom behaviors that differentiate students with LD from their non-disabled peers. Two scales of 83 items each were devised and piloted in 70 school districts. Five significant factors or subscales were identified through discriminant factor analyses. Two subscales and 18 individual items discriminate students later classified as LD and those referred but not subsequently classified as LD. Results are discussed, with implications for further investigation of behaviors that distinguish students with and without LD.  相似文献   
150.
Friendship Quality as a Predictor of Young Children's Early School Adjustment   总被引:13,自引:0,他引:13  
The purpose of this study was to develop a method for assessing young children's perceptions of classroom friendships and to determine whether these perceptions were associated with their adjustment during the transition to grade school. Subscales tapping 5 friendship processes (e.g., validation, aid, disclosure of negative affect, exclusivity, conflict) were extracted from a 24-item friendship interview that was individually administered to 82 kindergarten children ( M age = 5.61) who possessed a reciprocated and stable "best" friend in their classroom. Children's reports of the investigated friendship processes were found to be reliable, and processes such as perceived validation and conflict predicted children's satisfaction with their friendships, and the stability of these relationships. Perceived conflict in friendships was associated with multiple forms of school maladjustment for boys, including higher levels of school loneliness and avoidance and lower levels of school liking and engagement. For both boys and girls, validation and aid forecasted gains in perceived support from classmates, and aid also predicted improvements in children's school attitudes. Perceived exclusivity in friendships was associated with lower levels of achievement. These findings, and others reported in this article, are consistent with the hypothesis that the relational features of children's classroom friendships yield psychological benefits or costs (e.g., provisions) that, in turn, affect their development and adjustment.  相似文献   
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