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951.
The purpose of this study was to determine the degree of comparability between the WISC and the WISC-R over time. Hypotheses were tested using a sample of 276 mildly mentally handicapped children enrolled in special education classes who had received a WISC (Trial 1) and a WISC or WISC-R (Trial 2) after an interval of approximately three years. The sample was grouped on the basis of test administered in Trial 2. Group I contained those children who received the WISC on Trial 2 and included 183 children, of whom 121 were males and 62 were females. Mean age at time of initial testing was 8–10; mean age at second testing was 11–8. Group II was composed of 93 children who had been posttested on the WISC-R and included 72 males and 21 females. Mean age at initial testing was 9–5; mean age at posttest was 13–0. The study was conducted in five school districts and one county department of education. Verbal IQ, Performance IQ, and Full Scale IQ for both instruments administered were transcribed from the special education folders of the children. The design used to test hypotheses was repeated measures analysis of variance. Data analysis resulted in rejection of the hypotheses that the WISC-R yields mean Verbal, Performance, and Full Scale IQ scores greater than or equal to the corresponding mean IQ scores of the WISC. It was concluded that the WISC-R may unfairly penalize special education children who are reevaluated with this instrument. Fluctuations in IQ scores due to the instrument of measurement must be recognized, and appropriate action should be taken to insure that children are evaluated for special class placement on comparable bases.  相似文献   
952.
953.
    
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954.
Using data on the ‘career’ paths of one thousand ‘leading scientists’ from 1450 to 1900, what is conventionally called the ‘rise of modern science’ is mapped as a changing geography of scientific practice in urban networks. Four distinctive networks of scientific practice are identified. A primate network centred on Padua and central and northern Italy in the sixteenth century expands across the Alps to become a polycentric network in the seventeenth century, which in turn dissipates into a weak polycentric network in the eighteenth century. The nineteenth century marks a huge change of scale as a primate network centred on Berlin and dominated by German-speaking universities. These geographies are interpreted as core-producing processes in Wallerstein’s modern world-system; the rise of modern scientific practice is central to the development of structures of knowledge that relate to, but do not mirror, material changes in the system.
David M. EvansEmail:
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955.
近读李婷婷先生<周代乡乐考论>一文(载<中国文化研究>2007年夏之卷.文中简称"李文"),觉得颇有可议之处.今不揣谫陋,将若干大大小小不敢苟同之处,凡十二处,次第列出,加上拙按,幸方家有以教我.李文的问题,归纳起来,大体有以下三点.第一,"读书不统观首尾,不可妄下批评",这是陈垣先生<陈垣史源学杂文>一书中告诫后学的两句话,[1]笔者深深服膺,而纵观李文,颇有与此告诫相违者,拙文之第六、第十二条所论是也.第二,率尔操觚,贸然立论.拙文中第二、第五、第七、第十一条所论是也.第三,当简则繁,当繁则简,处置失当.例如,"何谓乡乐",这本来是一个给乡乐下定义的问题,竟然不避雷同地繁征博引五六百字,是所谓当简则繁.而所谓"郑玄、贾公彦及其后世之学者等在言及无算乐时,还将乡乐与无算乐混为一谈"这样一个大问题,本来应该多方举证,以证服人,而遗憾的是作者仅仅举了两个例子,还都不符合学术规范.梁启超说:"凡立一义,必凭证据.孤证不为定说."[2]前辈学者说:"例不十不立."诚哉斯言!  相似文献   
956.
明代"博杂"之学术特色根源于当时的博学思潮,而博学思潮之所以在明代发生又绝非偶然,究其原因,主要包括三个方面:思想文化渊源、科举制度和明代的政治思想现实及风气.其中,学术传统中的博学思想为博学思潮的发生奠定了坚实的思想基础;明代的科举制度和政治思想现实及风气在为空疏不学之风的滋长提供条件和制度保障的同时,也为博学思潮的发生准备了批判、反思的目标和对象,并提供了理论和实践以及学者群体上的保障,而这两个方面又是促成博学思潮在明代这一特定历史时期发生的决定性因素.  相似文献   
957.
Evidence of the importance of physique in the athletics disciplines is supported by the persistence of certain characteristics over long periods, despite marked secular changes in the source population. These characteristics may also result in physiological benefits such as effective thermoregulation or a greater power-to-weight ratio. Coaches and athletes are often convinced of weight or fat loss benefits based on personal or anecdotal experience, intuition, and "trained eye" observation of successful competitors. This may entice athletes into adopting unbalanced, erratic or highly restrictive eating patterns that increase the risk for nutrient deficiencies, and disordered eating. Despite heavy training loads and often extreme diets, some athletes fall short of their physique goals as ultimately phenotype is under genetic control. Professionals assisting athletes with physique management need to be highly skilled in anthropometry and require a thorough understanding of sports-specific nutrition requirements. Careful assessment of the risks and benefits of various approaches to weight and fat loss is required before they are recommended to athletes.  相似文献   
958.
Although the importance of high motivation to engage in deliberate practice has been acknowledged, no research has directly tested this hypothesis. Therefore, the present study examined this relation in adolescent elite chess players by means of a questionnaire. In addition, to provide an explanation for dropout among promising chess players, differences in motivation between persistent and dropout chess players were analyzed. Competitiveness and the will to excel proved to be predictors of investments in deliberate practice. Moreover, achievement motivation and chess-specific motivation differed to a certain extent between persisters and dropouts. Our results suggest that motivation to engage in deliberate practice not only contains elements of the will to improve performance, but also of the will to attain exceptional levels of performance.  相似文献   
959.
Excess protein intake can adversely affect the bone via an increase in calcium excretion, while suitable mechanical loading promotes osteogenesis. We therefore investigated whether vibration exposure could alleviate the bone mineral losses associated with a metabolic acidosis. Ten healthy individuals aged 22 - 29 years (median = 25) underwent three 5-day study periods while monitoring their dietary intake. The study consisted of recording the participants' usual dietary intake for 5 consecutive days. Participants were then randomly divided into two groups, one of which received a protein supplement (2 g x kg(-1) body mass x day(-1); n = 5) and the other whole-body low-magnitude (3.5 g), low-frequency (30 Hz) mechanical vibration (WBV) delivered through a specially designed vibrating plate for 10 min each day (n = 5). Finally, for the third treatment period, all participants consumed the protein supplement added to their normal diet and were exposed to WBV exercise for 10 min per day. Daily urine samples were collected throughout the experimental periods to determine the excretion of calcium, phosphate, titratable acid, urea, and C-telopeptide. As expected, when the participants underwent the high protein intake, there was an increase in urinary excretion rates of calcium (P < 0.001), phosphate (P < 0.003), urea (P < 0.001), titratable acid (P < 0.001), and C-telopeptide (P < 0.05) compared with baseline values. However, high protein intake coupled with vibration stimulation resulted in a significant reduction in urinary calcium (P = 0.006), phosphate excretion (P = 0.021), and C-telopeptide (P < 0.05) compared with protein intake alone, but did not affect titratable acid and urea output. The participants showed no effect of WBV exercise alone on urinary excretion of calcium, phosphate, urea, titratable acid, or C-telopeptide. The results indicate that vibration stimulation can moderate the increase in bone resorption and reduction in bone formation caused by a metabolic acidosis.  相似文献   
960.
The purpose of this study was to investigate young athletes' imagery use from a developmental perspective. The participants were 110 male and female athletes competing in both team and individual sports. They represented four different age cohorts (i.e., 7-8, 9-10, 11-12, and 13-14 years). Sixteen focus groups, two for each age category and gender, were used as the method of data collection. The findings indicated "where," "when, " and "why" young athletes use imagery and how imagery use changes as children move from early childhood through to early adolescence. Overall, results revealed that all age cohorts reported using imagery in both training and competition and for both cognitive and motivational purposes. The present research also found support for studying imagery use by young athletes from a developmental perspective.  相似文献   
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