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1.
Digitize-and-lend library projects can benefit societies in multiple ways, from providing information to people in remote areas or with physical disabilities to facilitating the sharing of library resources with information-poor communities. This article explores the potential of digitize and lend as well as outlines how projects can be undertaken in a manner respectful of the balance of copyright.  相似文献   
2.
The promotion of students’ achievement and competence in the so-called STEM disciplines is one cornerstone of current educational research and practice. In particular, as early as elementary school, the fostering of an adequate understanding of science is a normative goal of science education. It facilitates students’ science learning and enables them to understand the nature and development of scientific knowledge. Based on the relevance of the promotion of young children’s understanding of science, a corresponding science intervention was recently developed and successfully evaluated in a first study under highly controlled conditions. The goal of the present study was to investigate the effectiveness of this intervention when implemented in practice. One hundred seventeen third- and fourth-grade students and 10 trained course instructors participated in this study. We applied a randomized block design with waitlist control groups and repeated measures. The results revealed that children assigned to the intervention compared with children assigned to the waitlist control group showed better inquiry-related methodological competencies (a better understanding of the scientific inquiry cycle and experimentation strategies) and a higher need for cognition. The findings point to the successful implementation of the intervention and are compared with the results of the first study.  相似文献   
3.
ABSTRACT

We performed a randomized, controlled trial to analyse the effects of resistance training (RT) on cognitive and physical function among older adults. Fifty participants (mean age 67 years, ~60% woman) were randomly assigned to an RT program or a control group. Participants allocated to RT performed three sets of 10-15RM in nine exercises, three times per week, for 12-weeks. Control group did not perform any exercise. Variables included cognitive (global and executive function) and physical function (gait, mobility and strength) outcomes. At completion of the intervention, RT was shown to have significantly mitigated the drop in selective attention and conflict resolution performance (Stroop test: -494.6; 95%CI: -883.1; ?106.1) and promoted a significant improvement in working memory (digit span forward: -0.6; 95%CI: ?1.0; ?0.1 and forward minus backward: -0.9; 95% CI: ?1.6; ?0.2) and verbal fluency (animal naming: +1.4, 95%CI 0.3, 2.5). No significant between-group differences were observed for other cognitive outcomes. Regarding physical function, at completion of the intervention, the RT group demonstrated improved fast-pace gait performance (?0.3; 95% CI: ?0.6; ?0.0) and 1-RM (+21.4 kg; 95%CI: 16.6; 26.2). No significant between-group differences were observed for other mobility-related outcomes. In conclusion, RT improves cognitive and physical function of older adults.  相似文献   
4.
根据“念动练习法”的基本理论,突破武术教学只注重灌输式传授基本技术、技能忽略学生主观能动性培养的模式.通过教学实验证明,运用“念动练习法”教学策略可以提高学生的学习兴趣,增强学习的动机,从而提高高校太极拳选项课教学质量.  相似文献   
5.
在信号变换及电子测量中,电流源应用广泛,其性能优劣及结构特点对测量结果有直接影响。因此,在电子测量控制工程设计中应正确选用电流源电路结构及参数。  相似文献   
6.
文章首先论述了提出这个论题的必要性,接着从了解掌握一定的科学的性知识、树立健康的符合时代进步的性观念、在恋爱交友中用理智调控感情等三个方面重点具体地论证了论题。  相似文献   
7.
为防止大体积砼产生裂缝,采用HE微膨胀剂与LNF泵送剂行之有效。同时应进行温度应力与浇筑长度验算和精心施工。  相似文献   
8.
热量是由温度来定义的,因而用热冷程度来定义温度就是不科学的.本文以热力学第一定律和第二定律为基础,用可逆热机的运转来建立温度概念.温度是体系的单一决定可逆热机效率的宏观可测性质.此一宏观可测性质的特征由可逆热机运转的三种情形可以明确地揭示出来.  相似文献   
9.
存储混合型是目前研究较多的控制释放体系 ,但由于其机理较为复杂 ,目前尚未建立合理实用的动力学模型 .以混合药膜包膜体系为研究对象 ,建立了释放动力学的简化模型并获得了解析解 .实验数据表明 ,该模型适用于描述药物装填量大于饱和溶解度的药物释放动力学行为 (相对偏差小于 3 % ) .根据该模型还从理论上分析了两种限定条件 (Dm Df和 Dm Df)下药物的释放特征 :当 Dm Df时 ,释放速率变为常数 ,达到零级释放 ,其释放速率与药膜无关 ,这为零级释放缓释体系如何控制释放速率和药物释放量提供了理论依据 :当 Dm Df时 ,药物的释放速率与药膜中的释放系数、溶解度和药物的装填量有关 ,与包膜过程无关 ,其释放过程类似于混合药膜缓释体系  相似文献   
10.
The effects of photoperiod and light intensity on flowering in Mat Rush cv. Gangshan 3 were studied. The results showed that treatments with longer day length stimulated flowering significantly and increased stem flowering percentage (SFP). Plants treated with low light intensity at early stage had substantially reduced florets per cyme, SFP, tillers per plant and stem length. At middle and late stage, low light intensity significantly reduced SFP. The principal climatic factors affecting SFP were as follows: mean temperatures (MT) of the third ten-day period (TDP) in December and of the second TDP in February, actual sunlight hours (SH) of the third TDP in February and precipitation of the third TDP in March. A nonlinear simulation model for SFP was established with experimental results and corresponding climatic data (see Eq. (2)). Simulation by the above equation yielded values the same as those observed from 1992 to 2000, indicating its accuracy in describing the relationship between flowering and light and temperature conditions. The interaction between vernalization and SH is also discussed in this paper. Project (No. 981105) supported by the Ningbo City Science Foundation, China  相似文献   
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