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21.
Partnership in higher education emphasises an active role for students in both teaching and learning. This pedagogical culture is likely to make students assessment literate and engage them in deep learning. In this study, Iranian students experiencing learning-by-teaching (LbT) in private language institutes were interviewed to compare their perceptions toward assessment and learning with their counterparts without this experience. Findings show that LbT fosters students’ assessment literacy and deep learning. Results also reveal that by teaching other students, quasi-teachers promote a broader understanding of assessment and grade practices in comparison to other students. Unlike their counterparts, quasi-teachers de-emphasised grades and showed a greater focus on learning. Moreover, explaining the materials to other students provided them with a deeper cognitive process resulting in deeper learning. These results underscore the perceived importance of partnership in higher education.  相似文献   
22.
梁勇 《科技与管理》2006,8(2):124-126
针对于现今企业的信息交流的需要进行了分析研究,提出了在Windows2003 Server系统平台下使用Exchange 2003邮件软件和其前端软件Outlook 2003来为企业构建信息管理平台,实现企业中信息交换的电子信息化管理。  相似文献   
23.
中国已经进入老龄化社会,本文通过对中国人口老龄化状况的分析,指出老年人手机市场潜力巨大.老年人手机设计必须以创意和革新为首要条件,充分考虑老年人心理、生理、生活习惯等各方面的因素,并且符合人机工程学的要求,使手机设计真正体现出对老年人的尊重和关怀.  相似文献   
24.
摘要:人类的衰老过程受DNA编码信息、表观遗传学信息和环境因素的共同调控。DNA编码信息提供了合成生命所必需蛋白质的模板或蓝图,决定着人类的生命历程和最高寿限,而表观遗传学信息则提供了何时、何地以及如何应用DNA编码信息的指令。饮食、药物、体力活动等诸多环境因素可通过改变衰老相关基因的表观遗传学修饰,进而影响基因的开启与关闭,决定着个体寿命的长短。表观遗传学不但搭建起了环境—基因之间的桥梁或中介,而且把人类的寿限与寿命密切地联系在一起。规律运动作为一种环境表观遗传调制器,可在不影响DNA编码的前提下,通过诱导表观遗传学修饰改变调控衰老相关基因的表达水平,在延缓人类衰老进程中发挥着重要作用。本文从影响人类衰老过程的表观遗传调控机制入手,对规律运动在调控衰老过程端粒相关蛋白、脑衰老、糖脂代谢和肿瘤发生发展的表观遗传学机制研究进展进行综述,其目的在于从分子遗传学水平揭示运动干预延缓衰老之谜,为倡导通过增加体力活动实现健康老龄化提供科学依据。  相似文献   
25.
建立基于劳动互换的居家养老服务体系的可行性探究   总被引:1,自引:0,他引:1  
老龄社会是21世纪我国的重要国情并对社会保障体系提供完善保障功能提出了日益迫切的需求.然而,在未来相当长时期内我国社会保障体系难以独撑社会稳定发展所赋予的重任.建立基于劳动互换的为老服务体系,合理设计制度,将可以有效调动其他社会资源来弥补现行社会保障体系的不足,并使之发展成为社会保障体系的重要辅助力量,是集可行性、经济性、有效性于一身的最佳选择.  相似文献   
26.
Drawing on acculturation and social identity literatures, the present research extends on initial work on social group connectedness among older immigrants to examine in a quasi-experimental study the well-being benefits of participating in heritage culture groups. Older immigrant clients (N = 66) of six aged-care agencies in Australia were given diary booklets in which to complete a set of measures on selected days when they did or did not attend the agencies’ heritage culture group activities, over a 2-month period. Results showed that heritage group participation reduced loneliness and increased well-being. Future research should replicate and extend these findings to assist our understanding of how heritage culture group participation aids first-generation older immigrants with aging successfully in a foreign land.  相似文献   
27.
人体衰老机制的动态过程与影响因素   总被引:3,自引:0,他引:3  
衰老是指人体的结构和功能随着年龄的增长而逐渐衰退的过程,衰老是生命的自然的动态过程,影响衰老的因素有很多,通过总结概括,综述人体衰老机制的动态过程与影响因素.  相似文献   
28.
The life of shipboard cables will decrease due to the complex aging processes. In terms of the safety perspective, remaining life prediction of the cable is essential to maintain a reliable operation. In this paper, firstly, based on Arrhenius equation, residual life of new styrene-butadiene cable is calculated; result indicates that the degradation rate which changes with time is proportional to thermal temperature. Then second order dynamic model is adopted into the residual life prediction, combined with the time-temperature superposition method (TTSP), and a new residual life model is proposed. According to the accelerated thermal aging experiment data and Arrhenius equation, TTSP method demonstrates to be an efficient way for life prediction, and life at normal temperature can be estimated by this model. In order to monitor the state of styrene-butadiene cable more accurately, an improved residual life model based on equivalent environment temperature of cable is proposed, and life of cable under real operation is analyzed. Result indicates that this model is credible and reliable, and it provides an important theoretical base for residual life of cables.  相似文献   
29.
There have been many conflicting observations between the linear or curvilinear decline in maximal heart rate (HRmax) with age. The aim of this study was to determine if linear or curvilinear equations would better describe the decline in HRmax with age in individuals of differing cardiorespiratory fitness (CRF) levels. Treadmill cardiopulmonary exercise test (CPX) results from participants (1510 men and 1134 women; 18–76 years) free of overt cardiovascular disease were retrospectively examined using cross-sectional and longitudinal study designs. Participants completing ≥2 CPX with ≥1 year between test dates were included in the longitudinal analysis (325 men and 150 women). Linear and quadratic regressions were applied to age and HRmax for the whole cohort and respective CRF groups (high, moderate, and low, relative to age and gender normative values). To test for differences among linear, quadratic, and polynomial equations, the change in R2 (cross-sectional analysis) and Bayesian information criterion (BIC) (longitudinal analysis) from the linear to the more complex models were calculated. The quadratic or polynomial regression in the cross-sectional analysis, marginally improved the variance in HRmax explained by age compared to the linear regression for the whole cohort (0.2%), moderate fit group (0.3%), and low fit group (0.8%). With no improvements in the high fit group. BIC did not improve for any CRF category in the longitudinal analysis. In conclusion, the minimal differences among linear, quadratic, and polynomial equations in the respective CRF groups, emphasizes the use of linear prediction equations to estimate HRmax.  相似文献   
30.
运用Elman神经网络模型对2010—2050年河北省人口数进行预测,经过分析得出,河北省的人口老龄化具有以下几个特征:老年人口规模庞大,增长迅速;老龄化程度超前于河北省的经济发展水平,社会负担沉重;老年人口的高龄化趋势明显;老年人口的性别差异较大;老年人口的分布具有明显的差异性等。根据这些特征为河北省应对人口老龄化提供了一些对策建议。  相似文献   
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