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211.
在过去的二十年间,国际大规模学生评估主要对教育研究、学校体系和教育政策产生影响.本文着重介绍这些项目的主要结果,并在此基础上,于2003年在中国四个省份展开数学胜任力测试.作为过去几十年国际大规模学生评估的非参与国,中国无疑提供一个特殊视角.因而,本文所报告的中国学生成绩国际比较是一项独特工作. 相似文献
212.
Elif Balin Andreas Hirschi 《International Journal for Educational and Vocational Guidance》2010,10(3):161-176
This study investigated whether career adaptability, personality, attitude towards career counselling and some demographic
variables predict the help seeking behaviour in career counselling among 330 Swiss adolescents in eighth grade. The results
indicated that boys were less likely to seek help and that career related variables and attitude but not personality significantly
predicted help-seeking. Specifically, help seeking related positively to undecidedness and positive perception of career counselling.
Implications for school and career counsellors and suggestions for future research are presented. 相似文献
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Ohne Zusammenfassung 相似文献
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Hao Gao Cong Liu Andreas Hermann Richard J Needs Chris J Pickard Hui-Tian Wang Dingyu Xing Jian Sun 《国家科学评论(英文版)》2020,7(10):1540
Helium and methane are major components of giant icy planets and are abundant in the universe. However, helium is the most inert element in the periodic table and methane is one of the most hydrophobic molecules, thus whether they can react with each other is of fundamental importance. Here, our crystal structure searches and first-principles calculations predict that a He3CH4 compound is stable over a wide range of pressures from 55 to 155 GPa and a HeCH4 compound becomes stable around 105 GPa. As nice examples of pure van der Waals crystals, the insertion of helium atoms changes the original packing of pure methane molecules and also largely hinders the polymerization of methane at higher pressures. After analyzing the diffusive properties during the melting of He3CH4 at high pressure and high temperature, in addition to a plastic methane phase, we have discovered an unusual phase which exhibits coexistence of diffusive helium and plastic methane. In addition, the range of the diffusive behavior within the helium-methane phase diagram is found to be much narrower compared to that of previously predicted helium-water compounds. This may be due to the weaker van der Waals interactions between methane molecules compared to those in helium-water compounds, and that the helium-methane compound melts more easily. 相似文献
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We assessed autonomic nervous system modulation through changes in heart rate variability during an archery competition as well as archery performance by comparing novice and experienced adolescent archers. Seven novice (age 14.0 ± 8.5 years, body mass index 22.9 ± 4.3 kg · m(-2), training experience 0.4 ± 0.3 years) and ten experienced archers (age 16.5 ± 10.3 years, body mass index 22.4 ± 3.1 kg · m(-2), training experience 4.1 ± 0.9 years) volunteered. Using beat-by-beat heart rate monitoring, heart rate variability was measured for 20 s before each arrow shot during two rounds of competition. We found that, compared with novices, experienced adolescent archers: (i) take more time per shot; (ii) have a higher low frequency band, square root of the mean of squared differences between successive R-R intervals (i.e. the time elapsing between two consecutive R waves in the electrocardiogram), and percentage of successive normal-to-normal intervals greater than 50 ms; and (iii) demonstrate an increase in parasympathetic nervous system activity compared with pre-competition values. We propose that these characteristics of experienced archers are appropriate for optimal performance during competition. 相似文献