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The careful distinctions in this article assist in clarifying the tasks of educators  相似文献   
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Two groups of adults on AFPA pre-qualification training schemes were each exposed to a different programme, explicitly aimed at improving their cognitive skills: Ateliers de Raisonnement Logique/Logical Reasoning Workshops and Logo exercises. They were compared with a control group receiving special treatment, members being informed that they were participating in an experiment. This latter group was exposed, for an essentially similar period, to training in the use of office-work software and computer-assisted education. The three groups were tested, at the beginning and end of the scheme, on a number of cognitive dimensions. The level of self-esteem of participants, their attitude to computers and the internality of their attributions were also evaluated. Results showed: 1) a modest increase in cognitive efficiency in each group at the end of training and ambiguous variations in conative variables; 2) no superiority of the Logo group over the control group; 3) superiority of the ARL group for two cognitive variables of the ten studied (combinatory analysis and perceptive field independence). The extent of the difference was invariably less that one standard-deviation of the distribution of scores. These results, and in particular the absence of transfer of acquisitions, seem insufficient to justify the conclusion of any specific efficacy of this last method.  相似文献   
76.
This study is part of a larger research project at the Image Permanence Institute dedicated to digital print preservation issues – the Digital Print Preservation Portal (DP3). Previous DP3 studies determined that certain digital print types are prone to cracking and/or abrasion, and that factors such as low relative humidity, pollutants, and light increase the brittleness of the ink-receiving layer of some inkjet papers. The purpose of this investigation was to explore if light also increases the propensity of inkjet prints to abrade, and to examine the potential of framing glazings to mitigate light-induced physical damage (cracking and abrasion) by attenuating some portion of the UV spectrum. Inkjet papers and prints were subjected to xenon lighting (to simulate daylight through window glass) without glazing, or in sealed framing packages with plain framing glass (soda-lime) or UV filtering glass. Before and after light exposure, brittleness, and abrasion resistance were evaluated independently using two tests: ISO 18907 (Imaging materials – Photographic films and papers – Wedge test for brittleness) and a rub test utilizing a Sutherland® Rub Tester. In this study, exposure to light increased the cracking and/or abrasion tendency of some specimens. The use of UV filtering glass reduced this light-induced propensity in all cases. Plain glass protected all samples from at least one of these two types of surface damage, but was less effective than UV glass. Light-induced brittleness and sensitivity to abrasion were mostly, though not exclusively, caused by UV radiation. It was also seen that some prints may become brittle and/or prone to abrasion in the absence of image fade. Budgeting the amount of light these objects can be exposed to, protecting them from UV radiation, and handling prints with caution especially after exhibition, is essential in order to limit physical damage.  相似文献   
77.
We hypothesised that resiliency may protect adolescents against risky behaviours, and that both the practicing of sports, and gender are moderating variables in relationships between resiliency and risky behaviours. The study included 18-year-old pupils from a selection of secondary schools (n = 556). A total of 188 individuals practiced competitive sports and the remaining 368 participants were non-athletes. The participants were examined with the Resiliency Assessment Scale for Children and Adolescents (SPP-18) and with a survey containing questions and statements related to high-risk “experiments with adulthood”. Adolescent athletes showed higher levels of resiliency than their peers. The power of the “Determination and Persistence in Action” effect on “Alcohol” scale differed significantly between male athletes and male non-athletes. Only in the athletes groups were higher scores on this scale reflected by lower values on the “Drugs” scale. Moreover, it is possible to observe differences in undertaking risky behaviour between male and female athletes. The analysis of risky sexual behaviour suggests that sport is a risk factor for men, and a protective factor for women. These data suggest that consistent prophylactic and psycho-educative activities, with a special attention to differences between genders, should be provided to all the adolescents, irrespective of their sport performance levels.  相似文献   
78.
The purpose of this study was to investigate the effects of interval aerobic training combined with strength exercise in the same training session on body composition, and glycaemic and lipid profile in obese rats. Sixteen lean Zucker rats and sixteen obese Zucker rats were randomly divided into exercise and sedentary subgroups (4 groups, n = 8). Exercise consisted of interval aerobic training combined with strength exercise in the same training session. The animals trained 60 min/day, 5 days/week for 8 weeks. Body composition, lipid and glycaemic profiles and inflammatory markers were assessed.

Results showed that fat mass was reduced in both lean and obese rats following the exercise training (effect size (95% confidence interval (CI)) = 1.8 (0.5–3.0)). Plasma low-density lipoprotein–cholesterol and fasting glucose were lower in the exercise compared to the sedentary groups (= 2.0 (0.7–3.2) and 1.8 (0.5–3.0), respectively). Plasma insulin was reduced in exercise compared to sedentary groups (= 2.1 (0.8–3.4)). Some exercise × phenotype interactions showed that the highest decreases in insulin, homeostatic model assessment-insulin resistance, fasting and postprandial glucose were observed in the obese + exercise group (all, P < 0.01). The findings of this study suggest that interval aerobic training combined with strength exercise would improve body composition, and lipid and glycaemic profiles, especially in obese rats.  相似文献   

79.
The skeletal muscles and the fibrous connective tissue form an extensive, body-wide network of myofascial chains. As fascia can modify its stiffness, strain transmission along these meridians is supposable. The goal of this trial therefore was to collect pilot data for potential remote effects of lower limb stretching on cervical range of motion (ROM). Twenty-six healthy participants (30 ± 6 years) were included in the matched-pairs intervention study. One group (n = 13) performed three 30 s bouts of static stretching for the gastrocnemius and the hamstrings, respectively. An age- and sex-matched control group (CG; n = 13) remained inactive. Pre- and post-intervention, maximal cervical ROM in flexion/extension was assessed. A repeated measures ANOVA revealed systematic differences between groups (P < .05). ROM increased following stretching (143.3 ± 13.9 to 148.2 ± 14°; P < .05) but remained unchanged in the CG (144.6 ± 16.8 to 143.3 ± 16.8°; P > .05). Our data point towards existence of a strain transfer along myofascial meridians. Further randomised controlled studies on conditions, factors and magnitude of tensile transmission are warranted.  相似文献   
80.
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   
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