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121.
Chronic illnesses and disabilities may impair the attainment of age-typical developmental tasks, such as forming relationships with peers and gaining autonomy. Based on a systematic search in electronic databases and cross-referencing, 447 quantitative empirical studies were included which compared the attainment of developmental tasks of adolescents with and without chronic physical illness or physical/sensory disability. Adolescents with chronic illness or disability had more problems than healthy/nondisabled peers with regard to autonomy, body acceptance, developing friendships and romantic relationships, gaining access to a peer-group, career preparation, preparing for family life and developing socially responsible behaviour. However, between-group differences were small. No between-group differences were found regarding gender role acquisition and identity development. Success in solving developmental tasks varied, in part, by disease group, visibility of the disease/disability, age, gender and representativeness of the sample. Interventions aimed at promoting the attainment of developmental tasks are recommended.  相似文献   
122.
This work presents an array of microfluidic chambers for on-chip culturing of microorganisms in static and continuous shear-free operation modes. The unique design comprises an in-situ polymerized hydrogel that forms gas and reagent permeable culture wells in a glass chip. Utilizing a hydrophilic substrate increases usability by autonomous capillary priming. The thin gel barrier enables efficient oxygen supply and facilitates on-chip analysis by chemical access through the gel without introducing a disturbing flow to the culture. Trapping the suspended microorganisms inside a gel well allows for a much simpler fabrication than in conventional trapping devices as the minimal feature size does not depend on cell size. Nutrients and drugs are provided on-chip in the gel for a self-contained and user-friendly handling. Rapid antibiotic testing in static cultures with strains of Enterococcus faecalis and Escherichia coli is presented. Cell seeding and diffusive medium supply is provided by phaseguide technology, enabling simple operation of continuous culturing with a great flexibility. Cells of Saccharomyces cerevisiae are utilized as a model to demonstrate continuous on-chip culturing.  相似文献   
123.
本文首先提出了2个当代城市研究的个案,并批判了他们对于城市及其空间建构过程的片面性理解;其次,通过回顾经典的城市理论,本文梳理出了身体、空间和城市之间的相关性;最后,展开了关于当代城市理论的探讨,从空间组织形式的角度去探讨了身体与城市之间的实践关系。总体而言,本文在西方社会理论的脉络中探讨了身体、空间和城市等几个重要概念,并强调了对于"身体"概念的理解有助于我们更好地去理解城市及其内在逻辑。  相似文献   
124.
Reducing the mass of a racing wheelchair improves the winning time even for relatively small mass reductions over short distances (100 m). In this study, the improvement of speed and winning time on mass reduction was modelled mathematically, the speed profiles of 100 m wheelchair races as well as the rolling resistance and drag area of the athlete–wheelchair system was determined experimentally, and the improvement of the winning time through mass reduction was calculated from the mathematical model and experimental data. For winning times of 30 s, the relative improvement of the winning time is at least equal to the relative reduction of mass. For winning times of 15 s, the relative improvement of the winning time is at least half the relative reduction of mass. A reduction by 1 kg results in an overall improvement of the winning time of about 1–2.3% for winning times of 15–30 s (100-m race). In absolute terms, a mass saving of 1 and 5 kg on a 60-kg system would reduce a 15-s winning time for the 100 m by 0.132 and 0.66 s, respectively, and a 30-s winning time by 0.63 and 2.86 s, respectively. The mass of a wheelchair is the most important parameter for improving the winning time. The influence of the mass on the winning time is 4 or 1.5 times greater than the influence of the rolling friction coefficient, and 4 or 5.5 times greater than the influence of the drag area in a 15 or 30-s race, respectively. These principles should be considered when designing a racing wheelchair.  相似文献   
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From the perspective of preventive medicine and learning physiology it is important to introduce children and young people to effective aerobic endurance training. In the field study presented, boys and girls of school years 6, 8, 10 and 12 underwent 3 running tests of 12, 20 and 30 min duration and were tested for lactate concentration, heart rate and rate of perceived exertion (RPE). The physiological metabolic parameters were compared and recommendations for an appropriate long-term endurance test for school sport were given depending on the results. The 12 min running test provoked a higher average lactate concentration (5.3-10.9 mmol/l lactate) in both sexes of all school years than the 2 longer running tests. The average lactate concentrations, however, may be evaluated as quite harmless in school sport provided there is adequate preparation. The longer running tests also require sufficient preparation as they cause average lactate concentrations of approximately 4-8.5 mmol/l and obviously higher demands for volitional properties than shorter running tests. The 20 min running test can be considered as an alternative to the Cooper test (12 min running test): lactate concentrations in blood are between 18.5 % and 23?% lower on average and heart rates and RPE after the test are only slightly higher.  相似文献   
130.
The present study compared psychological adjustment of 158 adolescents with vision impairment and 158 sighted adolescents with a matched-pair design using the Strengths and Difficulties Questionnaire. Adolescent self-reports and teacher reports on emotional problems, peer problems, and total difficulties showed higher scores in students with vision impairment than in sighted students. However, the size of between-group differences was small, and adolescents who are blind and their peers with low vision showed similar levels of psychological adjustment. In addition, older students reported more emotional problems than younger students. Furthermore, differences between self-reported emotional problems of students with and without vision impairment were stronger in older participants. In both groups, girls showed more emotional problems and less conduct problems than boys. We conclude that most students with vision impairment are well adjusted but a minority may benefit from psychological interventions.  相似文献   
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