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151.
    
In 28 male Caucasian nonprofessional ultracyclists, we investigated whether anthropometry or training volume had an influence on race speed in the 600 km at the Swiss Cycling Marathon 2007. Anthropometric parameters (age, body mass, body height, skin-fold thicknesses) were determined before the race to calculate body mass index and percent body fat. In addition, participants, using a training diary, recorded their training volume in hours and kilometers in the 3 months before the race. The influence of anthropometry and training volume on speed in the race as the dependent variable was investigated in a multiple linear regression model. Anthropometry showed a moderate association with speed in the race (r2 = .178, p < .05), whereas training volume showed no association (r2 = .000, p > .05). We concluded that anthropometry had a greater influence on race performance than training volume in recreational ultraendurance cyclists.  相似文献   
152.
The present experiment investigated the effects of kinship and familiarity upon food sharing in pairs of albino rat pups. Five pairs of rats from each of the following groups were tested: (1) familiar siblings, (2) nonfamiliar siblings, (3) familiar nonsiblings, and (4) nonfamiliar non-siblings. A small food portion was used, necessitating not only close physical contact, but also cooperation in the sense that both pups were required to remain relatively immobile in order for both to feed simultaneously. Results indicated more frequent sharing among unfamiliar pups, whether related or not. Results also indicated that food sharing increased in frequency among all four groups over the 5-day testing period, suggesting that cooperation in the form of food sharing can develop, or increase in frequency, over time in albino rat pups.  相似文献   
153.
Differences in family factors in determining academic achievement were investigated by testing 432 parents in nine independent, coeducational Melbourne schools. Schools were ranked and categorized into three groups (high, medium and low), based on student achievement (ENTER) scores in their final year of secondary school and school improvement indexes. Parents completed a questionnaire investigating their attitudes towards the school environment, their aspirations, expectations, encouragement and interest in their child’s education (adapted from scales constructed by Marjoribanks). They also responded to six open‐ended questions on their attitudes to achievement and to their (child’s) school. Multiple regression analyses revealed that parental expectations of their children’s educational level made the strongest unique prediction of high achievement followed by the length of time they had maintained their expectations. Limitations discussed include the disparity in meaning associated with the definition of school success and whether these results can be generalized to all students considering the biased sample (socio‐economic status).  相似文献   
154.
Bioelectrical impedance vector-analysis (BIVA) describes cell-mass, cell function and hydration status of an individual or a group. The goal of the present investigation was to provide bioelectrical impedance data for 525 male road cyclists (155 professionals, 79 elite, 59 elite-youth, and 232 amateurs) at the time of their optimal performance level. Data were plotted on the resistance-reactance (R-Xc) graph to characterize cyclists group vectors using BIVA. Compared to the general male population, the mean vector position of the road cyclists indicates a higher body cell mass (BCM) and phase angle (p<0.001). The vector position of the high-performance, compared to the amateur cyclists showed similar patterns with higher BCM and phase angles and higher reactance values for the high-performance athletes (p<0.001). The bio-impedance data were used to calculate the 50%, 75%, and 95% tolerance ellipses of each group of cyclists. The characteristic vector positions of the road cyclists indicate normal hydration and greater muscle mass and function of the high-performance cyclists compared to amateur cyclists and the normal population. The cyclists specific tolerance ellipses, particularly the high-performance cyclists might be used for classifying a cyclist according to the individual vector position and to define target vector regions for lower level cyclists.  相似文献   
155.
    
Teacher turnover in urban schools is occurring at a breakneck pace; thus, it is important for us to understand the characteristics of teachers who stay and succeed in these settings. In order to address this need, this study examines the preparation and induction experiences of teachers who completed a Transition to Teaching – a funded urban apprenticeship program. Three research questions guided the study: (1) How do participants describe the characteristics that influence their five-year retention? (2) How do participants describe their success as teachers? and (3) How do participants describe the professional support they received in their preparation program and during the subsequent four years after completing the program? Quantitative and qualitative data via interviews, focus group, and an examination of teachers’ district performance scores were utilized, as a means of understanding teachers’ staying and impact power. Staying power refers to the ability to endure or last within challenging contexts by possessing strength enough to persevere. Impact power refers to their ability to influence student learning. Four assertions describe the factors influencing developing teachers who stay and have impact as they teach in challenging urban schools, suggesting that these teachers possess a strong work ethic, seek specific resources to improve pedagogy, have the knowledge and skills necessary to differentiate instruction, and seek teacher leadership opportunities in their schools. This study suggests several implications for teacher educators, educational leaders, administrators, and researchers working with new teachers in urban schools or with populations that are predominantly children of color.  相似文献   
156.
    
It is an accepted fact that resilience is a multifaceted phenomenon which has been proven to affect the learning, growth and development of individuals. A child’s formative years are a time when resilience needs to be promoted so they can cope with the challenges of life. This paper reports some of the findings of an Australian Research Council-funded longitudinal study which investigated resilience in the context of significant transitions in the lives of children and young adults. This study explored the conditions and characteristics of resilience, looking at the educational, health, work-related or leisure interventions that support and foster resilience. Outlined in this paper are findings from the early years cohort of the study involving teachers’ pedagogy informing the practical approaches and strategies that promote and protect resilience in young children. It is argued that teachers working with young children need to be mindful of using enabling strategies in which their practice works purposively with the school environment and the building of relationships.  相似文献   
157.
This paper examines how the relationship between firm value and patent-based indicators of inventive activity has changed over time. We use data from more than 33,000 mergers and acquisitions deals between 1985 and 2007, and distinguish between American (USPTO) and European (EPO) patents. Our results indicate that over time EPO patents have become the dominant indicator of innovative activity, while USPTO patents have no effect on firm value near the end of the sample period. The results are robust to controlling for citations and are especially strong for small firms, for firms operating in the drug and chemical industries, and when target and acquiring firms operate in different industries or countries.  相似文献   
158.
A multidisciplinary approach is implemented to model and analyse the performance of Olympic rowing boats. A reduced-order model that couples rowers motions with the hull, oars and hydrodynamic and hydrostatic forces is detailed. This model is complemented with a sensitivity analysis carried out by means of a non-intrusive polynomial chaos expansion. Sensitivity analysis results for two different boat classes, namely, a lightweight single scull and a coxless four are presented and discussed. This analysis contrasts, for both classes, the effects of varying forces exerted by the rowers, weights of rowers and cadence of motions on the boat performance.  相似文献   
159.
160.
    
Pigeons were trained to depress a treadle in the presence of a discriminative stimulus, either a tone or illumination of red houselights, in order to obtain access to grain or avoid electric shock. In avoidance training, the auditory discriminative stimulus yielded faster acquisition than did the visual one. In appetitive training, the visual discriminative stimulus yielded faster acquisition than the auditory one. Experiments 2 and 3 used these stimuli in Kamin’s (1969) blocking design. In Experiment 2, when the pigeons were trained to depress a treadle in the presence of tone to obtain grain and then red light was added as the redundant stimulus, the light acquired stimulus control over treadlepressing; blocking was not observed. In Experiment 3, when the pigeons were trained to depress a treadle in the presence of red light to avoid electric shock and then tone was added as the redundant stimulus, the tone acquired stimulus control over treadle-pressing. Again, blocking was not observed. The implications of these results for several models of stimulus control are discussed.  相似文献   
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