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L. Girolametto S. Bonifacio C. Visini E. Weitzman E. Zocconi P.S. Pearce 《International Journal of Early Years Education》2003,11(3):255-260
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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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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Kwafo-akoto KO 《Aslib proceedings》1988,40(4):105-110
Acquiring both published and unpublished documents produced in Africa is, generally, a difficult task due to the existing poor state of bibliographic control and the publishing industry. It is even more difficult to obtain unpublished documents in a specialized area of study such as demography--a diffuse area which cuts across several disciplines. This paper discusses the problems encountered on acquisition trips to some African countries to acquire unpublished population material. To help solve the problems, the Population Association of Africa must persuade its members to send copies of their publications to population libraries and documentation centers in their individual countries for dissemination to the other users in Africa. The various organizations and institutions in Africa engaged in the teaching and research of population studies should have an agreement to exchange copies of their theses. The Economic Commission for Africa (ECA) and the Organization of African Unity (OAU) should make representations to the various African member countries on the need to disseminate the results of vital censuses and surveys conducted. Finally, the Population Information Network for Africa (POPIN-AFRICA) with its coordinating unit at the population division of ECA should ensure that all the nodes of the network have the financial and other resources to be able to acquire the relevant documents needed for their operations. 相似文献