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51.
The aim was to examine cross-cultural variation in linguistic responsiveness to young children in 10 English-speaking mother–child dyads and 10 Italian-speaking mother– child dyads. All 20 children were late talkers who possessed delays in expressive vocabulary development but age-appropriate cognitive and receptive language skills. Dyads were filmed in 15 minute free play contexts, which were transcribed and coded for measures of maternal linguistic input (e.g. rate, MLU, labels, expansions) and child language productivity (e.g. utterances, different words used). The results revealed that the Italian mothers used more utterances, spoke more quickly and used a more diverse vocabulary than the Canadian mothers. The Italian children mirrored their mothers and also used more utterances and a more diverse vocabulary than the Canadian children. Mothers in both groups used similar percentages of responsive labels and expansions. However, Italian mothers responded to fewer of their children's vocalisations, using a smaller percentage of imitations and interpretations than the Canadian mothers. Correlations between maternal input and children's language productivity revealed that contingent language measures (e.g. imitations, interpretations, expansions) were related to high levels of productivity in children in both cultural groups. The results support the use of language interventions based on increasing maternal responsiveness for these children at the one-word stage of language development. They also point to differences that may be culturally based. For example, Italian mothers use faster rates of interaction and appear to have higher expectations for their children's verbal participation in interaction. This is reflected in higher rates of language production from their children, even though children in both cultural groups have similar vocabulary sizes.  相似文献   
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无盘网络与数字图书馆   总被引:2,自引:0,他引:2  
通过无盘网络与有盘网络的比较,提出无盘网络作为新图书馆部分网络选型的解决方案以及无盘网络在数字图书馆中的应用。  相似文献   
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中小馆通用编目子系统的设计与开发   总被引:1,自引:0,他引:1  
针对中小型图书馆编目工作的特点,分析了传统计算机编目系统的不足之处,提出了相应的修改意见,并给出了一个中小馆通用编目子系统的基本设计结构和实现方案。  相似文献   
54.
数字参考服务:发展与思考   总被引:100,自引:2,他引:98  
数字参考服务是网络环境下参考服务发展的一种新形式。本文探讨了数字参考服务的深刻内涵,阐述了它的起源、服务模式、工作机制、应用领域以及最新发展趋势。在此基础上,根据我国数字参考服务发展的现状,提出了我国图书馆开展数字参考服务应考虑的主要问题。  相似文献   
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体态语言在体育教学中的应用   总被引:12,自引:0,他引:12  
语言是体育教学的第一要素。体育教学语言除了“口头语言”及“书面语言”外,还有“体态语言”,其表达的准确清晰程度在体育教学过程中起着至关重要的作用。  相似文献   
58.
An investigation has been undertaken at St Andrew’s church, Walpole St Andrew, Norfolk, to establish the underlying causes of the observed stone decay to the upper parts of the six stone piers. The stone decay was first recorded in the early 1930s. The salt-contaminated masonry within the church has been shown to undergo severe salt decay during the summer, with little damage occurring over the winter months. The south aisle piers have been shown to decay 2.5 times faster than the north aisle piers. Although crystallization–hydration cycles have been identified, the rate of decay is at its greatest when the cycling is relatively infrequent. This was not the expected trend. Furthermore, it has been shown that during extended periods where the ambient relative humidity is less than 75%, the rate of decay reaches a maximum. It is the length of this ‘drying’ period that apparently has the greatest influence on the rate of decay and could explain the significant difference in the rate of decay between the south and north aisle piers. The results have serious implications for passive conservation, where it is often recommended to lower the ambient relative humidity to well below the equilibrium relative humidity of the salt contaminant, to avoid crystallization–hydration cycles. Since, at the time of building, the church was situated on the coast, it is possible that the sodium chloride contamination occurred during the building process (1440–1520), particularly since the area was prone to sea-flooding at this time. Alternatively, the salt could have been applied as a treatment during the general restoration of 1897. Whatever the source of the salt, it seems likely that the ambient environment was changed by the insertion of a sealed floor in 1897, which could account for the onset of the salt decay.  相似文献   
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农业土壤碳储量和碳固定是全球变化及碳循环研究值得关注的重要问题.水稻土是我国主要的农业土地利用类型.水稻土有机碳在全球变化背景下的作用有待深入研究.本研究以安徽省为例,采用的基本资料是第二次土壤普查资料,各类型土壤剖面有机质含量、厚度、容重数据取自<安徽土壤>、<安徽土种>,其中部分土壤容重数据采用的是平均值.估算安徽省水稻土表层有机碳库的储量为0.0918Pg,其中耕层为0.0527Pg,犁底层有机碳库为0.0391Pg.总碳密度为4.167kg/m2,耕层土壤平均有机碳密度为2.655kg/m2,犁底层平均碳密度为1.757kg/m2.  相似文献   
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