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51.
The objective of this study was to determine which chemical treatment used for disinfecting water in indoor swimming pools had the least impact on users' perceptions of health problems, and which generated the greatest satisfaction with the quality of the water. A survey on satisfaction and perceived health problems was given to 1001 users at 20 indoor swimming pools which used different water treatment methods [chlorine, bromine, ozone, ultraviolet lamps (UV) and salt electrolysis]. The findings suggest that there is a greater probability of perceived health problems, such as eye and skin irritation, respiratory problems and skin dryness, in swimming pools treated with chlorine than in swimming pools using other chemical treatment methods. Pools treated with bromine have similar, although slightly better, results. Other factors, such as age, gender, time of day of use (morning and afternoon) and type of user (competitive and recreational), can also affect the probability of suffering health problems. For all of the above, using combined treatment methods as ozone and UV, or salt electrolysis produces a lower probability of perceived health problems and greater satisfaction.  相似文献   
52.
The present study examined the influence of momentum sequence (positive vs. negative) and environmental climate (hot–wet vs. neutral) on supporters’ (i.e. virtual observers’) reported levels of perceived psychological momentum (PM) during a simulated cycling competition. Participants supported one of two competing cyclists involved in a race that was displayed on a screen in a lecture hall. The race scenario was manipulated so that the supported cyclist appeared to undergo either a positive or negative momentum sequence. In addition, participants were either exposed to a hot–wet environmental climate or to a neutral environmental climate while observing the race scenario. According to the results, reported levels of PM were higher in the positive momentum sequence condition than in the negative momentum sequence condition, consistent with the notion that supporters’ PM is influenced by a positivity bias, and reported levels of PM were also found to be higher in the hot–wet climate condition than in the neutral climate condition, consistent with the notion that environmental climate is a contextual factor that influences PM through the operation of a causal augmenting mechanism.  相似文献   
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This study investigated the immediate effects of reducing the shoe drop (i.e. the difference between the heel and the forefoot height) on the kinematics and kinetics of the lower extremities of children tennis players performing a tennis-specific movement. Thirteen children tennis players performed a series of simulated open stance forehands wearing 3 pairs of shoes differing only in the drop: 0 (D0), 6 (D6) and the control condition of 12?mm (D12). Two embedded forceplates and a motion capture system were used to analyse the ground reaction forces and ankle and knee joint angles and moments of the leading lower limb. In D6 compared with D12, the peak impact force was reduced by 24% (p?=?.004) and the ankle was less dorsiflexed at foot strike (p?=?.037). In D0 compared with D12, the peak impact force was reduced by 17% (p?=?.049), the ankle was less dorsiflexed at foot strike (p?=?.045) and the knee was more flexed at foot strike (p?=?.007). In addition, 4 out of 13 participants (31%) presented a forefoot strike pattern for some of the trials in D0. No difference was observed across shoe conditions for the peak knee extensor moment (p?=?.658) or the peak ankle plantarflexor moment (p?=?.071). The results provide preliminary data supporting the hypothesis that for children tennis players, using a 6-mm lower shoe drop might reduce heel impact forces and thus limit potentially impact-related injuries.  相似文献   
54.
The aim of this study was to determine whether, as a result of collaborative-online reading of a chapter from a book of an academic nature, the quality of the collaborative summary that the readers would write would be higher than that written by readers who would both read the same chapter and write a summary in a face-to-face setting. In this study we examined the difference between the summaries written by participants from two groups, each group was divided into subgroups of 3 participants who had read collaboratively a chapter of a book, and collaborated on writing a summary. The participants of the experimental group read the chapter as it appeared in a website for collaborative reading built especially for this study and the participants were asked to summarize the chapter on a shared online digital document. The participants of the control group were asked to read the chapter face-to-face and to collaboratively summarize it in hand writing. The quality of the summaries was evaluated with a tool developed by Rivard (2001). This tool was developed to measure the quality of the summaries. In our study the main and secondary ideas that were supposed to be included in the participants’ summaries were identified by three literature teachers using ten different criteria and the summaries were analyzed by two other judges based on these criteria. The findings indicated that there were significant differences in the majority of the writing indicators being measured with the tool. The findings indicated that collaborative-online reading and writing produce a summary of a higher quality than one read and hand written collaboratively face-to-face.  相似文献   
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Enhanced reality     
Goéry Delacôte 《Prospects》1997,27(2):265-274
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57.
Five suburban community colleges in a metropolitan area collaborated on a survey to parents of high school graduates of the class of 2002 who attended the colleges in fall 2002. The study was undertaken to learn more about parents roles in their students selection of community colleges, to give insights and information about this important community college constituency, and to assist community colleges to shape more effective ways to foster positive and supportive opinions among parents of potential students. Parents want the community college to provide students with credits and grade point averages enabling transfer, overestimate their students academic skills as measured by course placement tests, engaged in a number of college-choice activities, and indicate that factors associated with lifestyle and money were major reasons for selecting the community college. Associations between parents social capital and perceptions of their students academic abilities were found for a number of dependent variables examined. The study also revealed important differences in how participating institutions record and calculate key measures such as credits earned and grade point averages.  相似文献   
58.
学习“三个代表”的重要思想 ,必须坚持理论联系实际的马克思主义学风。要深入把握“三个代表”重要思想的理论根据和实践根据 ,更要研究怎样切实有效地实践“三个代表”。  相似文献   
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We investigated differences between field-study classrooms and traditional science classrooms in terms of the learning environment and students’ attitudes to science, as well as the differential effectiveness of field-study classrooms for students differing in sex and English proficiency. A modified version of selected scales from the What Is Happening In this Class? questionnaire was used to assess the learning environment, whereas students’ attitudes were assessed with a shortened version of a scale from the Test of Science Related Attitudes. A sample of 765 grade 5 students from 17 schools responded to the learning environment and attitude scales in terms of both their traditional science classrooms and classrooms at a field-study centre in Florida. Large effect sizes supported the effectiveness of the field-studies classroom in terms of both the learning environment and student attitudes. Relative to the home school science class, the field-study class was considerably more effective for students with limited English proficiency than for native English speakers.  相似文献   
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