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1.
At the turn of the last century there was an ever increasing world demand for pearls while at the same time their known fishing grounds were becoming exhausted. Some way of artificially increasing their production was obviously desirable, and the problem attracted considerable effort. It was an attempt to exploit a scientifically poorly understood phenomenon, and it is interesting, in retrospect, to relate these attempts to recent concepts of biomineralisation. Pearls are, of course, the layers of aragonitic calcium carbonate secreted by molluscs. 相似文献
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Umeda T Nakaji S Shimoyama T Yamamoto Y Totsuka M Sugawara K 《Journal of sports sciences》2004,22(4):329-338
In this study, we examined the effects of weight reduction by restricting energy intake on muscle function and serum concentrations of myogenic enzymes in judoists. Twenty-seven male judoists aged 19.3 +/- 0.6 years (mean +/- s) were divided into three groups based on the extent of body weight reduction: high weight reduction (height 1.70 +/- 0.05 m, body mass 78.5 +/- 13.6 kg), low weight reduction (height 1.70 +/- 0.05 m, body mass 80.7 +/- 13.1 kg) and a group that maintained body weight while continuing to perform exercise training (height 1.78 +/- 0.07 m, body mass 78.7 +/- 8.8 kg). Body composition, blood biochemistry, energy intake and anaerobic power were assessed on four occasions: 20 days (baseline data), 4 days and 1 day before and 7 days after competition. Compared with baseline, body mass and fat-free mass were significantly lower 1 day before competition in the high and low weight reduction groups (both P < 0.01); these changes persisted for 7 days after competition in the high weight reduction group. Serum creatine kinase was significantly elevated 1 day before competition in all groups (all P < 0.05), and remained higher 7 days after competition in both the high and low weight reduction groups. Compared with baseline, maximal anaerobic power was significantly lower 1 day before competition only in the high weight reduction group (P < 0.01). Our results suggest that energy restriction in addition to intense exercise training before major competition has an adverse effect on anaerobic power and elevates serum creatine kinase concentration, leading to an impairment of muscular function and an increased susceptibility of muscle tissue to injury. 相似文献
3.
Masanori Yamada Satoshi Kitamura Hideya Matsukawa Tadashi Misono Noriko Kitani Yuhei Yamauchi 《Educational technology research and development : ETR & D》2014,62(5):529-553
In recent years, collaborative filtering, a recommendation algorithm that incorporates a user’s data such as interest, has received worldwide attention as an advanced learning support system. However, accurate recommendations along with a user’s interest cannot be ideal as an effective learning environment. This study aims to develop and evaluate an online English vocabulary learning system using collaborative filtering that allows learners to learn English vocabulary while expanding their interests. The online learning environment recommends English news articles using information obtained from other users with similar interests. The learner then studies these recommended articles as a method of learning English. The results of a two-month experiment that compared this system to an earlier collaborative filtering system called “GroupLens” reveal that learners who used the collaborative filtering system developed in this study read various news articles and had significantly higher scores on topic-specific vocabulary tests than did those who used the previous system. 相似文献
4.
David Mueller Andrew Giacomazzi James Wada 《Journal of Criminal Justice Education》2013,24(2):201-218
Questionnaire data from 137 panel chairs at the 2003 Academy of Criminal Justice Sciences meeting in Boston reveal respondent perceptions of the conference site, overall impressions of the conference, as well as panelist attendance, and the quality of information presented by panelists. The findings reveal high marks for the conference space, hotel rooms, and the city of Boston itself, resulting in an overall positive conference experience, but responses also highlight several areas of concern, including panelist attendance problems and presentation etiquette. Recommendations are provided, which may foster positive, incremental change at future ACJS annual meetings. 相似文献
5.
The demand for higher education facing an individual institution 总被引：1，自引：0，他引：1
The purpose of this paper is to provide an estimate of the elasticity and cros-selasticities of demand for higher education facing an individual institution. The utility which a high school graduate derives from each educational option open to him is assumed to be a stochastic function of the attributes of that option. For certain types of utility functions the maximization of utility results in the logit probability model. This model is used to analyze the choices made by a sample of high school graduates in Hawaii. Estimates of the price elasticity and the cross-price elasticities of demand for enrollment at the University of Hawaii are obtained. It is found that the demand is quite inelastic with respect to both tuition and total cost of education. These estimates imply that changes in tuition will not affect enrollment appreciably.The authors wish to express their appreciation to Arthur S. Goldberger, H. Laurence Miller, and Pan A. Yotopoulos for their comments on earlier drafts of the paper. 相似文献
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Tadashi Endo 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》2003,8(1):97-109
Based on field research in Irkutsk and Khabarovsk, this paper examines the consequences of the diversification policy in education and culture after the collapse of the Soviet regime in 1991. It reports on work conducted by a team of Japanese researchers. The paper investigates the nature of decentralisation in education, giving particular attention to the rise of the private sector and the education of ethnic minorities. Highlighting the similarities and differences between the two regions within the national framework, it shows the value of intra-national as opposed to cross-national comparative studies. 相似文献
8.
Tadashi Endo 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》2003,49(1-2):97-109
Based on field research in Irkutsk and Khabarovsk, this paper examines the consequences of the diversification policy in education and culture after the collapse of the Soviet regime in 1991. It reports on work conducted by a team of Japanese researchers. The paper investigates the nature of decentralisation in education, giving particular attention to the rise of the private sector and the education of ethnic minorities. Highlighting the similarities and differences between the two regions within the national framework, it shows the value of intra-national as opposed to cross-national comparative studies. 相似文献
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Takashi Umeda Shigeyuki Nakaji Tadashi Shimoyama Youske Yamamoto Manabu Totsuka Kazuo Sugawara 《Journal of sports sciences》2013,31(4):329-338
In this study, we examined the effects of weight reduction by restricting energy intake on muscle function and serum concentrations of myogenic enzymes in judoists. Twenty-seven male judoists aged 19.3±0.6 years (mean±s) were divided into three groups based on the extent of body weight reduction: high weight reduction (height 1.70±0.05?m, body mass 78.5 ±13.6?kg), low weight reduction (height 1.70±0.05?m, body mass 80.7±13.1?kg) and a group that maintained body weight while continuing to perform exercise training (height 1.78± 0.07?m, body mass 78.7±8.8?kg). Body composition, blood biochemistry, energy intake and anaerobic power were assessed on four occasions: 20 days (baseline data), 4 days and 1 day before and 7 days after competition. Compared with baseline, body mass and fat-free mass were significantly lower 1 day before competition in the high and low weight reduction groups (both P?<0.01); these changes persisted for 7 days after competition in the high weight reduction group. Serum creatine kinase was significantly elevated 1 day before competition in all groups (all P?<0.05), and remained higher 7 days after competition in both the high and low weight reduction groups. Compared with baseline, maximal anaerobic power was significantly lower 1 day before competition only in the high weight reduction group (P?<0.01). Our results suggest that energy restriction in addition to intense exercise training before major competition has an adverse effect on anaerobic power and elevates serum creatine kinase concentration, leading to an impairment of muscular function and an increased susceptibility of muscle tissue to injury. 相似文献