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21.
Report on Day 2     
Abstract

This is a ‘view from the coalface’ of someone who runs a large company responsible for the training of other member companies of the Group of which it forms a part. He gives examples from the day‐to‐day work of his company, and looks to the future of open and distance learning in the industrial world.  相似文献   
22.
23.
This study investigated the acute endocrine responses to a 164-km road cycling event in a hot environment. Thirty-four male experienced cyclists (49.1 ± 8.3 years, 86.8 ± 12.5 kg, 178.1 ± 5.1 cm) participating in a 164-km road cycling event were recruited. Blood samples were collected within 0.3–2.0 h before the start (PRE: ~0500–0700 h) and immediately following the ride (POST). Samples were analysed for testosterone, growth hormone (GH), cortisol and interleukin-6 (IL-6). The temperature and humidity during the event were 35.3 ± 4.9°C and 47.2 ± 14.0%, respectively. Based on the finishing time, results for the fastest (FAST, 305 ± 10 min) and the slowest (SLOW, 467 ± 31 min) quartiles were compared. At POST, testosterone concentration was significantly (P < 0.05) lower (PRE, 20.8 ± 8.6; POST, 18.2 ± 6.7 nmol · L?1), while GH (PRE, 0.3 ± 0.1; POST, 2.3 ± 0.3 µg · L?1), cortisol (PRE, 661 ± 165; POST, 1073 ± 260 nmol · L?1) and IL-6 (PRE, 4.0 ± 3.4; POST, 22.4 ± 15.2 pg · mL?1) concentrations were significantly higher than those at PRE. At POST, GH and cortisol were significantly higher for the FAST group than for the SLOW group (GH, 3.6 ± 2.0 and 1.0 ± 0.8 µg · L?1; cortisol, 1187 ± 209 and 867 ± 215 nmol · L?1). Participation in an ultra-endurance road cycling event in a hot environment induced significant acute changes in concentrations of circulating hormones, with a greater augmentation of GH and cortisol in those completing the ride fastest.  相似文献   
24.
The purpose of this study was to examine the mediating effect of resistance training skill competency on percentage of body fat, muscular fitness and physical activity among a sample of adolescent boys participating in a school-based obesity prevention intervention. Participants were 361 adolescent boys taking part in the Active Teen Leaders Avoiding Screen-time (ATLAS) cluster randomised controlled trial: a school-based program targeting the health behaviours of economically disadvantaged adolescent males considered “at-risk” of obesity. Body fat percentage (bioelectrical impedance), muscular fitness (hand grip dynamometry and push-ups), physical activity (accelerometry) and resistance training skill competency were assessed at baseline and post-intervention (i.e., 8 months). Three separate multi-level mediation models were analysed to investigate the potential mediating effects of resistance training skill competency on each of the study outcomes using a product-of-coefficients test. Analyses followed the intention-to-treat principle. The intervention had a significant impact on the resistance training skill competency of the boys, and improvements in skill competency significantly mediated the effect of the intervention on percentage of body fat and the combined muscular fitness score. No significant mediated effects were found for physical activity. Improving resistance training skill competency may be an effective strategy for achieving improvements in body composition and muscular fitness in adolescent boys.  相似文献   
25.
The steady-state electrical conductivity,as well as the dielectric propertiesbetween 2×10~(-4)Hz and 100 kHz,and at 1 GHz,are reported for urease compressed powdersamples of low hydration.The results show that the large,low frequency dielectricdispersion,known as α-dispersion,is due to the build-up of a space charge of protons atthe sample-electrode interfaces.A smaller dispersion,appearing at higher frequencies,isconcluded to be associated with hindered motions of the peptide residues in the molecularstructure of urease.The extent of these polypeptide backbone motions is shown to bestrongly depended on the extent of enzyme hydration.This work is contributed to the de-velopment of conductimetric biosensors.  相似文献   
26.
The purpose of the study was to examine the relationship of classroom environment to attitudes toward science and achievement in science among tenth grade biology students. An attitude instrument was administered at three times during the school year to measure student attitudes toward science and the classroom environment. The classroom environment measures examined six areas: emotional climate of the science classroom, science curriculum, physical environment of the science classroom, science teacher, other students in the science classroom, and friends attitudes toward science. Student achievement in science was measured by teacher reported semester grades. The results of the study indicated: (1) student attitudes toward the classroom environment predicted between 56 to 61% of the variance in attitudes toward science, (2) student attitudes toward the classroom environment predicted between 5 to 14% of the variance in achievement in science, (3) student attitudes toward science and attitudes toward the classroom environment predicted between 8 and 18% of the variance in achievement in science.  相似文献   
27.
The current study examines the association between parental support and adolescent sleep under varying levels of family stress. Participants included 316 adolescents (Mage = 16.40 years, 43% male) and their parents (Mage = 45.67 years, 91% mothers) from diverse ethnic backgrounds. Both adolescents and parents completed questionnaires and adolescents wore wrist actigraphs and completed self‐reports on their sleep for 7 consecutive days. Results indicated that under contexts of family stress, more parental support was linked to longer sleep duration, less sleep variability, and less time spent awake during the night. Findings suggest that under contexts of family stress, cohesive family relationships may provide a sense of stability and security that is necessary for healthful sleep.  相似文献   
28.
The purpose of this study was to determine if achievement on a series of problems was affected by differences among task values within a dimension. Values within inference pattern, goal object, and percept dimensions were studied. One hundred and sixty primary school children participated in the study. An analysis of the results of their achievement on the tasks indicate that task solution is affected by the dimension values used in this study. The results of the study suggest that a multidimensional scale of task dimension values should be constructed in order to assist the curriculum specialist in the construction and sequencing of concept tasks for specific grade levels.  相似文献   
29.
This study assessed the perceptions of 146 gifted and 115 non-gifted high school biology students and investigated associations between student perceptions and cognitive achievement. The What Is Happening In this Class? (WIHIC) was used to assess perceptions of actual and preferred learning environments. Data indicated that all students preferred a more favourable environment than the one that they were currently experiencing, but gifted students perceived their actual environment more positively than non-gifted students. Statistically significant associations between the actual learning environment and achievement on a standardised biology test were found for the majority of scales. Teacher Support, Investigation and Equity were all statistically significant independent predictors of student achievement, while Student Cohesiveness had a negative association with achievement. Interviews revealed that students interpreted some WIHIC items differently from how the developers had intended.  相似文献   
30.
Education as a liberating and democratic process remains an aim and belief in discourses within the field and beyond. The arts also have a tradition in which ‘artistic freedom’ is valued even if what constitutes artistic freedom is contested. In this article an educational discourse in which dialogue is considered a means to personal and collective liberation through education is highlighted and related to ‘artistic freedom’ and the dual roles of artist and teacher, in which learners and teachers are encouraged to contribute to and change culture as well as study and absorb it. Conceptualisations of the artist teacher and professional development and practices associated with these are considered to open up creative possibilities for art teachers without undermining other positive aspects of identity as a teacher and practitioner.  相似文献   
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