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991.
The purpose of this synthesis is to summarize the effectiveness of peer‐mediated interventions on the mathematics performance of both students with disabilities and those at risk for mathematics disabilities. Meta‐analytic techniques were used to calculate mean effect sizes for 17 studies that met inclusion criteria. Results indicate that peer‐mediated interventions in mathematics are moderately effective for improving students' mathematics performance. Also, findings are strongest for students at risk for mathematics disabilities, elementary‐aged participants, and mathematics computation content. Recommendations for future research and practical implications are discussed.  相似文献   
992.
993.
Leena Rao 《Resonance》2007,12(8):65-75
This article deals with various ‘supported’ acid catalysts developed as alternatives for the conventional ones in organic synthesis. They have advantages such as producing less toxic waste and using less energy.  相似文献   
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996.
Early and continued participation in a work-site health and fitness program   总被引:1,自引:0,他引:1  
This study examines social-environmental, physical-behavioral, and psychological factors influencing early and continued participation in physical activity. Data for the study were collected during the first six months of operation of a work-site Health and Fitness Center. The following sources were used to collect data (N = 403): 1) printouts of frequency of employee visits to the Health and Fitness Center; 2) a questionnaire; and 3) fitness files. Data measuring early (month one) and continued (month six) participation were obtained from printouts of frequency of employee visits. A questionnaire measured estimation of physical ability, attraction to physical activity, youth participation, social support, and convenience of the Health and Fitness Center. Fitness files were used to obtain measures of cardiovascular fitness, percent body fat, and recent participation. Linear discriminant analysis was conducted to determine the practical usefulness of the social-environmental, physical-behavioral, and psychological factors for classifying employees into categories of exercise adherers and nonadherers. A measure of exercise adherence was based on company policy of six visits each month. Results for early participation (month one) indicated that convenience, sex, youth participation, attitudinal commitment, and age discriminated (p less than .05) among adherers and nonadherers with 63% accuracy. At the end of six months, attitudinal commitment, sex, convenience, and estimation of physical ability discriminated (p less than .05) among adherers and non-adherers with 60% accuracy. In addition, when early participation in the health and fitness program served as the measure of recent participation for the six month analysis, recent participation and attitudinal commitment discriminated (p less than .05) between the two adherence categories with 75% accuracy. Adherers and nonadherers were classified with 66% and 85% accuracy, respectively.  相似文献   
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The experiences of medical students, residents, and faculty with a computerized literature searching system were evaluated. Third-year medical students, internal medicine and family practice residents, and full-time and voluntary faculty at one medical school had the opportunity to use a full-text and bibliographic medical literature retrieval system free of charge for an eleven-month period. Subjects conducted nearly nine thousand literature searches over a period of 942 system hours. Questionnaire data showed that participants could learn to use and would use an electronic information system, felt capable of using the system, utilized the system for a variety of purposes and in a number of different ways, and viewed the system as a valuable tool in searching the medical literature. The results are discussed in the context of the educational needs of the four user-groups and medical education planning by institutions.  相似文献   
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Many librarians affiliated with regional depositories are concerned about the ability of their libraries to receive, process, store, and service all the titles and series available on deposit from the Government Printing Office. Some of them have even questioned whether their library can maintain regional status and fulfill all the service elements specified in the Guidelines for the Depository Library System (1977). As this article demonstrates, regional librarians supported the concept of state plans because they believed that this process offered an excellent means to address their concerns. However, in only a few instances have the plans fulfilled the purpose which regional staff envisioned. Nonetheless, the foundation which they laid, if pursued and if the basic documentation underlying the depository program are rewritten, could lead to the type of changes sought by regional libraries.  相似文献   
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