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111.
This article examines the content and methodology of studies on Tai Chi as a sport in health care. We investigate the concept behind the rather simple name “Tai Chi,” concluding that this concept is manifold and highly variable. How did researchers deal with this variability when studying the effects of Tai Chi as a health-care intervention? We then explore how scientific research on Tai Chi has been conducted to date and draw the interim conclusion that the variability was barely taken into consideration. Our analysis of seven Tai Chi interventions reveals that two interventions referred to as Tai Chi may differ considerably in their content. The variability poses difficulty in repeating the intervention and drawing causal inferences. This problem is discussed in the current literature under the term “complexity in health-care interventions.” On the basis of a summary of this debate, we discuss the challenge of researching Tai Chi from a complex perspective—with the aim of achieving solid results that can be repeated.  相似文献   
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A survey was conducted in eight secondary schools located in two watersheds in Gujarat and Rajasthan (semi-arid region of India) to assess students’ perceptions about groundwater scarcity issues and the impact of the scarcity on their educational opportunities. Survey responses to a detailed questionnaire by a cohort of students in both watersheds; school attendance records of year 8 class students (13–14 years old) and responses gathered via a socio-economic survey involving 500 families in the study area were used in the study. In both watersheds, >90% students identified groundwater scarcity as a major issue. Required to work at home or farm, about 65% students in Gujarat and 60% in Rajasthan missed school for up to 2 days/month; and a smaller proportion (~ 30%) missed schools for 4 or more days/month. School absenteeism was found to be linked with gender; female students missed schools more frequently than their male counterpart. The school attendance records in Rajasthan showed that the frequency of female students missing schools for 5 or more days/month was on an average 2–10 times greater than that for males. The gender difference in absenteeism in all schools was statistically significant (P?<?.018**). The study highlighted that groundwater scarcity in the study area, and consequent demand on their time for household work including fetching drinking water are contributing factors towards limiting their educational and economic opportunities. Groundwater scarcity can be one of the key factors that can limit inclusiveness and empowerment of women and need to be considered in policy-making.  相似文献   
115.
Child-directed (CD) speech segments produced by 20 mothers who varied in self-reported symptoms of depression, recorded during a structured play interaction with their 2- to 6-month-old infants, were used as conditioned stimuli with face reinforcers in a conditioned attention paradigm. After pairings of speech segments and faces, speech segments were assessed for their ability to increase time spent looking at a novel checker-board pattern (summation test) using 225 4-month-old infants of nondepressed mothers. Significant positive summation, an index of associative learning, was obtained in groups of infants tested with speech produced by mothers with comparatively fewer self-reported symptoms of depression (Beck Depression Inventory or BDI < or = 15). However, significant positive summation was not achieved using speech samples produced by mothers with comparatively more symptoms of depression (BDI > 15). These results indicate that the CD speech produced by mothers with symptoms of depression does not promote associative learning in infants.  相似文献   
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Students’ mathematical problem-solving experiences are fraught with failed attempts, wrong turns, and partial successes that move in fits and jerks, oscillating between periods of inactivity, stalled progress, rapid advancement, and epiphanies. Students’ problem-solving journals, however, do not always reflect this rather organic process. Without proper guidance, some students tend to ‘smooth’ out their experiences and produce journal writing that is less reflective of the process and more representative of their product. In this article, I present research on the effectiveness of a persona-based framework for guiding students’ journaling to reflect the erratic to-and-fro of the problem-solving process more accurately. This framework incorporates the use of three personas—the narrator, the mathematician, and the participant—in telling the tale of the problem-solving process. Results indicate that this persona-based framework is effective in producing more representative journals.  相似文献   
117.
This paper examines the need for re-evaluating archival principles and practices. Opportunities created to enhance and enrich archival work and difficulties of archiving digital information, because of its nature, are reviewed. “Records series” are used to illustrate the consequences in terms of selection and appraisal of records. The preservation of digital information also raises new challenges. The impact of digital information on the ethical, legal and societal issues (protection, confidentiality, privacy, etc.) is emphasized.  相似文献   
118.
The Competitive State Anxiety Inventory-2 (CSAI-2) is one of the most frequently used instruments when assessing competitive state anxiety in sport psychology research. However, doubts have been expressed about the factorial validity of both the English and the Greek versions of the scale. Hence, a revised version of the inventory (CSAI-2R) has recently been suggested to be more psychometrically sound (Cox et al., 2003). In the present study, the aim was to evaluate the psychometric properties of the Swedish version of the CSAI-2 using confirmatory factor analyses. A total of 969 athletes (571 men and 398 women) competing in 26 different sports completed the Swedish version of the CSAI-2. Three different factor structures were evaluated: the original three-factor model (with cognitive anxiety, somatic anxiety and self-confidence), a two-factor model in which self-confidence was excluded, and a three-factor model containing 17 items (CSAI-2R). The results revealed that only the 17-item model displayed an acceptable fit to the data. Although some doubts remain about the amount of variance that can be attributed to error variance in the subscales, the results suggest that it is better to use the CSAI-2R rather than the original CSAI-2.  相似文献   
119.
The paper presents a model that evaluates how upgraded technological capabilities of emerging country based multinationals (EMNCs) and an increase in the domestic market size of large emerging countries affect value chain location choices and the competitiveness of emerging country based firms versus advanced country based ones. The model shows that, even without possessing a competitive advantage in terms of technology and/or brands, EMNCs from large or rapidly technologically advancing countries can become dominant players in the global system. The model highlights the central role of firm level technological intensity and product differentiation in determining the location of value chain activities as well as defining organisational boundaries. Empirical analysis of the location choices of the world's top multinationals from large advanced and emerging countries in 2010 supports the model's predictions.  相似文献   
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Children are capable of viewing object ownership as categorical and exclusive, but ownership claims can also vary by degree. This study investigated how children use these different conceptions of ownership in a giving and a taking task. In two studies, 4- to 7-year olds (= 105) could give and take craft objects that they or another child had found (weaker claim) and made (stronger claim). In Study 1, no additional ownership information was given, and in Study 2 categorical ownership was stated (“these belong to you”). The results showed that children used categorical ownership for their own objects but used ownership strength for the other child's objects, taking more of the found items.  相似文献   
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