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A report is given of the investigation of the iodine content of oyster shells taken from the reefs found in the Gulf of Mexico. The pulverized shells as sold on the market contain 200 to 300 parts per billion of iodine. Water soluble and alcohol soluble iodides appear to be absent. The granulated undried shells contain 500 parts per billion of iodine. Apparently there is a loss of iodine due to the temperature at which the pulverized shells are dried. 相似文献
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Understanding Leadership in Major Sporting Events: The Case of the 2005 World Aquatics Championships
The purpose of this paper was to begin understanding leadership within a major sporting event. A case study of the 2005 Fédération Internationale de Natation (FINA) World Aquatics Championships was built by means of interviews and archival material, using a multi-stakeholder perspective. Findings highlighted that core elements of upper-management level leadership in events were best described by the multiple-linkage leadership theory, which includes task commitment, ability and role clarity, work organization, cooperation and mutual trust, resources and support, and external coordination as the six intervening variables. While charismatic and transformational leadership styles surfaced as contributing to the overall success of an event, the multiple-linkage leadership theory offered a more comprehensive understanding of leadership in major sporting events from a multi-stakeholder perspective. 相似文献
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Christopher F. Sharpley Geraldine M. Parsons Helen Tillinh 《Psychology in the schools》1989,26(4):411-414
The effects of three routine classroom tasks upon heart rate reactivity were investigated with a sample of 30 typical fifth-grade children. Instructions for a mental arithmetic task, the mental arithmetic task itself, and silent reading were administered under standardized conditions, with a reward being offered for performance on the mental arithmetic task to enhance competition. Heart rate was individually monitored each second during these tasks, and data were collected on mental arithmetic performance and reading ability. Results indicated that some children showed large increases in their heart rates during the three tasks, and that these children should be considered as at-risk in terms of their cardiac health. 相似文献
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The study assessed the effects of achievement standards, and choice of such standards, on mathematics performance in conditions where no tangible rewards were presented for reaching such standards. Elementary, junior high, and high school students performed a multiplication task in conditions where they chose standards, had standards imposed by an experimenter, or had no standards. Results demonstrated that high school students worked more multiplication problems when they chose standards than when identical standards were imposed by an experimenter or when no standards were present. Moreover, male students who chose standards worked more problems than did male students who had no standards; this effect was not found for female students. 相似文献