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81.
Non-exercise equations developed from self-reported physical activity can estimate maximal oxygen uptake (VO(2)max) as well as submaximal exercise testing. The International Physical Activity Questionnaire (IPAQ) is the most widely used and validated self-report measure of physical activity. This study aimed to develop and test a VO(2)max estimation equation derived from the IPAQ-Short Form (IPAQ-S). College-aged males and females (n = 80) completed the IPAQ-S and performed a maximal exercise test. The estimation equation was created with multivariate regression in a gender-balanced subsample of participants, equally representing five levels of fitness (n = 50) and validated in the remaining participants (n = 30). The resulting equation explained 43% of the variance in measured VO(2)max (SEE = 5.45 ml·kg(-1)·min(-1)). Estimated VO(2)max for 87% of individuals fell within acceptable limits of error observed with submaximal exercise testing (20% error). The IPAQ-S can be used to successfully estimate VO(2)max as well as submaximal exercise tests. Development of other population-specific estimation equations is warranted. 相似文献
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The major findings and conclusions of a survey of manpower in health sciences libraries of the United States in 1969 are summarized. Although there does not appear to be a serious manpower shortage in terms of budgeted positions which are unfilled (demand), the manpower situation can still be considered serious when we introduce into our evaluation of the situation the question of existing levels of training and the urgent requirement (need) to bring manpower levels to a point at which adequate information services can be provided to the whole health sciences community. This is the final paper in a series of papers on a manpower study which also summarizes and analyzes the manpower data obtained by the American Hospital Association survey of 1968 and presents a number of general conclusions and recommendations for manpower planning for health sciences libraries. 相似文献
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Li FZ Jin SH Hu GC Fu YP Si HM Jiang DA Sun ZX 《Journal of Zhejiang University. Science. B》2005,6(8):803-811
A rice pse(t) (premature senescence, tentatively) mutant line, was isolated from 4500 independent T-DNA inserted transgenic lines. The symptoms of premature senescence appeared more severely than those of the control plants (Zhonghua 11,japonica) at the last development stage. To characterize the mutant and provide basic information on the candidate genes by mapping to a physical region of 220-kb, experiments were carried out in two phytotrons under controlled temperature of 24 ℃ and28 ℃, respectively. The content of chlorophyll, soluble protein and MDA (malondialdehyde), net photosynthesis, the antioxidant enzyme activities of SOD (superoxide dismuase) (EC 1.15.1.1) and POD (peroxidase) (EC 1.11.1.7) and the peptidase activities of leaves were measured from top to bottom according to the leaf positions at the flowering stage. Compared with the control plant,the mutant showed the following characteristics: (1) Higher net photosynthesis rate (Pn) appeared in the 1 st and 2nd leaves, contents of chlorophyll and soluble protein were also higher in the 1 st leaf; (2) The activities of SOD, POD and peptidase were higher according to the leaf position from top to bottom; (3) The symptom of premature senescence was accelerated in the mutant at 28℃treatment. The MDA content and the SOD and POD activities between the 24 ℃ and 28 ℃ treatment mutants were not significantly different. Content of chlorophyll and soluble protein of leaves mutant decreased rapidly at 28 ℃ treatment. The results show that pse(t) is sensitive to high temperature. The probable function of PSE(T) is discussed. 相似文献
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Bays DA 《Journal of learning disabilities》2004,37(3):256-261
School-level administrative support has been identified as an essential component of programs that promote research to practice. In this discussion, I address the critical role that school leaders play in supporting special educators and ensuring effective instruction for students with learning disabilities. Emphasis is placed on the need for teachers to be supported by administrators who are knowledgeable about special education and for administrators to receive the preparation and guidance they require to support science in contemporary schools. 相似文献
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The role of psychological interpretations in the relationship between low socioeconomic status (SES) and physiological responses was tested. One hundred high school students (ages 15–19) watched videos of ambiguous and negative life situations, and were interviewed about their interpretations. Lower SES was associated with greater threat interpretations during ambiguous (but not negative) situations and with greater diastolic blood pressure and heart rate reactivity. Threat interpretations partially mediated relationships between SES and reactivity. General life events (e.g., lack of positive life events), rather than specific life events (e.g., exposure to violence), partially explained the relationship between low SES and threat interpretations. Results suggest that the larger social environment helps explain how adolescents approach new social situations, which in turn has implications for adolescent physical health. 相似文献
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当你乍一看到Salvador Dali的绘画(左)中间的图象时,你看到了什么?大多数人的第一印象都是一个男人的脸——两眼凝望着天空,浓密的髭须下嘴唇噘起。当你定睛再看时,这幅图象又变成了一幅更为复杂的画面。男人的鼻子和白色髭须原来是一个坐着的女人的帽子和披肩。他眼里的微光成了坐落在黑暗山坡上的两座村庄里窗户的闪光——或是天花板的反光。 相似文献
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