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41.
42.
Dinghy sailing is a physically challenging sport with competitors on water for several hours. Regulations and space in the boat limit the amount of food and fluid competitors can carry. Consequently, it is possible that the hydration and nutritional status of dinghy sailors may be compromised while racing. Despite this, the food and fluid intake of sailors while racing are unknown. The aim of this study was to assess the dietary intake of a group of club sailors while racing and compare this with current sports nutrition guidelines. Thirty-five sailors (9 females, 26 males) were monitored during a club regatta. Body mass changes were measured before and after racing, as were food and fluid intake. Results showed that most participants were in negative fluid balance after racing (males: mean -2.1%[95% confidence limits -1.7 to -2.5%]; females: -0.9%[0 to -1.8%]), most likely due to low voluntary fluid intake (males: 1215 ml [734 to 1695 ml]; females: 792 ml [468 to 1117 m]). Carbohydrate intake (males: 59 g [21 to 97 g]; females: 30 g [0 to 61 g]) was below recommendations for normal sports activity. Results revealed that the nutritional practices of club sailors do not comply with current sports nutrition guidelines. However, the performance implications of a compromise in nutrient intake remain to be investigated. Practical advice on methods of overcoming space limitations for the carriage of adequate fluid and food is offered. 相似文献
43.
Carolyn Slater 《Learning, Media and Technology》1982,8(1):37-45
While television has portrayed the law and lawyers as an entertainment over the years, until recently the legal profession has had little to do with television. Lately, however, television has been used with considerable success and increasing frequency as an instructional medium in the continuing education of lawyers in Scotland. The author describes the background and early experiments in the use of television and demonstrates some of the ways in which television is now contributing to the training work of the Law Society of Scotland. 相似文献
44.
45.
Patricia L. Hardré Ching-Huei Chen Su-Hua Huang Chen-Ting Chiang Fen-Lan Jen Leslie Warden 《Asia Pacific Journal of Education》2006,26(2):189-207
The purpose of this research is to investigate predictive relationships among student characteristics that influence motivation for learning and achievement. A non-Western sample was chosen to test the generalisability of findings outside the Western cultural and social models. The participants were 6,539 students from 14 public high schools distributed across the western half of Taiwan. They were from three grade levels, and were balanced in gender. Correlations, analysis of variance, and multiple regression analyses were conducted. Individual differences predicted classroom perceptions, and perceptions predicted motivation, as did goal structures and group differences. Findings can inform educational policy, as well as teacher professional development and practice. 相似文献
46.
经扫描电镜观察,我国常绿栎类的叶表皮共发现有10种不同类型的毛,它们分别是:单列毛、单
分枝毛、泡状毛、莲座毛、单毛、束毛、短柄束毛、多出毛、星状毛和并合星状毛。 不同的分类单位有不同
毛类型的组合。所有常绿栎类的叶表皮上都出现有非腺毛类型的毛,而腺毛则仅限于某些分类单位
中。这两种基本类型的毛在结构和功能上有着本质的区别,分别代表了物种的生存适应方式和进化途
径。按叶表皮毛的基本类型将我国常绿栎类划分为腺毛类群和非腺毛类群两个类群,支持将常绿栎类
分成高山栎组(Sect.Suber(Reichenb.)Spach)和巴东栎组(Sect.Englerianae(A. Camus)Hsu et
Jen)的分组处理。综合叶表皮毛的类型、密度以及分枝特征提出了我国常绿栎类各分类单位之间的亲 缘关系图。 相似文献
47.
青藏古植被的演变与青藏高原的隆起 总被引:2,自引:0,他引:2
徐仁 《中国科学院研究生院学报》1982,20(4):385-391
西藏北部,在早石炭世晚期位于欧亚古陆的南缘,其植物群与当时印度次大
陆的不同。在晚二叠世,藏北属华夏植物区(即大羽羊齿植物区);印度河-雅鲁
藏布江大断裂带以南的地区出现舌羊齿植物群, 因而属冈瓦纳古陆的一部分。
到晚三叠世藏北植物群的面貌与我国西南同时代的植物群相似,与印度的则迥
然不同,显示藏北晚三叠世的植物群与南半球植物群也没有直接联系。 柴达木
侏罗纪植物群和拉萨附近早白垩世植物群与北半球的植物群有密切的关系。日
喀则晚白垩世植物群和阿里早始新世植物群也是如此。他们与印度德干玄武岩
夹层中出现的古新世植物群和印度北部始新世植物群也没有联系。 当时,西藏
的北部和南部属于两个不同的古陆,欧亚古陆和冈瓦纳古陆。 两者之间应有一
个很宽阔的特提斯海。因而,青藏的植物化石强有力地支持了大陆漂移的观点,
印度地块在晚侏罗世—白垩纪时是由非洲东南隅分离向北漂移,到始新世才与
亚洲连接,成为现在的南亚次大陆。 欧亚大陆与印度地块的接合线或许就是印
度河-雅鲁藏布江大断裂带。
从晚石炭世到早始新世的植物群的性质上看,藏北地势多半低洼。
中新世时,西藏中部和北部的植被是以落叶阔叶林为主,虽然某些地区有一
些常绿树存在,反映在中新世以前西藏中部和北部的地面已经上升到一定的程
度。在上新世时,藏北的常绿阔叶林逐渐减缩。柴达木盆地的植被转变成落叶
阔叶林-针叶林,以后转变成草原和半荒漠或荒漠,显示西藏和青海的地面进一
步抬升。
到晚上新世,藏北和青海的植被再行演变。然而,喜马拉雅地区的植被仍然
具有常绿栎林和雪松林。可能那时喜马拉雅山不像现在那么高。印度洋的季风
可以吹过喜马拉雅山,没有高山的阻碍。
第四纪是青藏山系和青藏地面上升最剧烈的时期。此时藏北已无常绿阔叶
树的存在。 到第四纪后期西藏大部分地区的植被逐渐演变为高寒荒漠。 最后, 青藏高原变成现在的情况。 相似文献
48.
This exploratory study examined the contribution of the RC Approach over a two‐year period. The RC Approach integrates social and academic learning in order to produce classroom environments that are conducive to learning by integrating social and academic learning. Two questions are addressed. First, how does teachers' use of RC practices contribute to children's academic and social growth? Second, how is the relation between teachers' use of RC practices and children's academic and social growth moderated by the presence of environmental adversity in the home? Participants included 62 teachers and 157 children at six schools. Findings showed that teachers' use of RC practices was associated with students' improved reading achievement, greater closeness between teachers and children, better pro‐social skills, more assertiveness, and less fearfulness, even after controlling for family risk and children's previous years' performance. Family risk did not moderate the relation between RC practices and children's performance. These findings suggest to the positive contribution of the RC Approach in relation to children's gains over a one‐year period. © 2007 Wiley Periodicals, Inc. Psychol Schs 44: 397–413, 2007. 相似文献
49.
Filling in the gaps in what humans see is a fundamental perceptual skill, but little is known about the developmental origins of occlusion perception. Three experiments were conducted with infants between 2 and 6 months of age to investigate perception of the continuity of an object trajectory that was briefly occluded. The pattern of results across experiments provided little evidence of veridical responses to trajectory occlusion in the youngest infants, but by 6 months, perceptual completion was more robust. Four-month-olds' responses indicated that they perceived continuity under a short duration of occlusion, but when the object was out of sight for a longer interval, they appeared to perceive the trajectory as discontinuous. These results suggest that perceptual completion of a simple object trajectory (and, by logical necessity, veridical object perception) is not functional at birth but emerges across the first several months after onset of visual experience. 相似文献
50.
Chubko Nadezhda Morris Julia E. McKinnon David H. Slater Eileen V. Lummis Geoffrey W. 《Educational technology research and development : ETR & D》2020,68(6):3587-3604
Educational technology research and development - This research compared the process of disciplinary literacy acquisition of students who experienced two different pedagogical approaches to... 相似文献