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961.
In an attempt to improve the knowledge of the quality of the thesauri-based databases (DB), a Spanish professional user group was surveyed in order to uncover DB thesaurus quality factors. Factor analysis methodology was applied to the data matrix gathered from users' opinions on a restricted sample of social science DB thesauri. Using processes of exploration, explanation, and interpretation, researchers reduced the initial 39 variables to 4 main components, regarded as the main DB thesaurus quality factors. These four main components are conceptual framework, performance, format, and external aids. They may provide scholars with four approaches to the issue of thesaurus quality and the points where further research is needed.  相似文献   
962.
Portugal is well known for its facades decorated entirely with ornamented glazed ceramic wall tiles called azulejos. On ageing, the tiles may detach and fall off, or deteriorate to such an extent that it becomes necessary to replicate them. Hence tile replication is a common practice in Portugal for façade restoration, but very often these new tiles do not have the same physical and/or chemical properties as the original ones. Such differences might be a factor in differential deterioration of the façades after restoration. One step toward an improvement in compatibility is to make new ceramic bodies with the same characteristics as the original ones. This study focuses on two types of glazed ceramic wall tiles from the Oporto region in Portugal: ‘calcic faience’ and pó de pedra. A total of 25 samples from the late nineteenth to early twentieth centuries were studied systematically as an attempt to improve knowledge of these materials and to create a basis for their replication. All samples were collected from facades that were under conservation/restoration at the time when sampling was performed. The original traditional ceramic bodies were analyzed by X-ray diffraction and X-ray fluorescence. Total open porosity, capillary absorption coefficient, and mercury intrusion porosimetry were also measured in order to gain knowledge on their physical characteristics in addition to their chemical and mineralogical compositions. High-temperature crystalline phases such as diopside, gehlenite, and mullite were found in the calcic faience, suggesting that the firing temperature of calcic faience bodies was within the range of 1100–1150?°C. Calcination trials were also performed in order to determine the most probable firing temperatures of the ceramic bodies. Collected data led to the assumption that the raw materials used for the ceramic bodies were kaolinitic clay, quartz sand, limestone, and talc. The raw materials for pó de pedra tiles were found to include kaolinite clay and quartz with firing temperatures estimated within the temperature range of 1150–1360?°C. Technical replicas made on the basis of these investigations were found to have the same mineralogical and capillary properties as the original tiles.  相似文献   
963.
Keith Haring painted large outdoor murals in Melbourne, Australia, in 1984 (the Collingwood Mural) and at Pisa in Italy in 1989 (Tuttomondo). Recently, both murals have been analyzed and conserved by similar teams of conservators and scientists. The original appearance of the Collingwood Mural was severely compromised, and the original materials much degraded. Tuttomondo was somewhat altered visually but with less physical damage. There were initial suggestions to repaint Tuttomondo but these were dissipated by good communication of the analytical findings. In Melbourne, there was a high-profile and emotive campaign to have the Collingwood Mural repainted. Conservators and government were heavily criticized for supposedly ignoring the artist's wishes. However, detailed research into Haring's published statements revealed that conservation does respect his artistic aims. For the Collingwood Mural, conservators had to consider whether to reduce the visual disturbances which obscured the works. Practices documented by conservation theorists and routinely undertaken by conservators guided the decision to apply mechanically reversible re-integration. This made Haring's unique ‘line’ visible and accessible again, and pleased the public. The controversies showed how conservators must communicate clearly and tactfully; appreciate the feelings of the public and involve communities in conservation, without compromising rigorous scientific and curatorial research.  相似文献   
964.
Purpose: This study explores the use of advisory services by farm managers and its linkages with the economic, environmental and social performance of farms.

Design/methodology/approach: Using cluster analysis we determined groups of farms according to their sustainability performance and explored the correlations between contacts with advisory services and a set of farm-level sustainability indicators.

Findings: There exist significant differences in the number of farmers’ contacts with advisory services across countries, type of farms, farmers’ degree of agricultural education, utilized agricultural area, legal type of farm ownership and economic size of the farms. We identified three groups of farms that have different sustainability performance, are different in farm characteristics and relate differently to advisory services. The number of contacts with advisory services is positively related to the adoption of innovations, the number of information sources utilized and the adoption of farm risk management measures. We find no clear linear relationship between advisory services and environmental sustainability.

Theoretical implications: This study derives hypotheses to analyze causalities between indicators of farm-level sustainability and advisory services.

Practical implications: Results suggest the importance of taking into account the heterogeneity of farming systems for the design, targeting and evaluation of advisory services. In addition, results confirm the importance of selection of indicators that can be used in multiple sites.

Originality/value: We used a harmonized indicator of advisory services and a harmonized set of farm-level sustainability indicators in nine different EU countries that could be used to evaluate the role of advisory services in the achievement of multiple objectives in different groups of farms in multiple sites.  相似文献   

965.
Cultural Studies of Science Education - Over the past decade, neoliberal practices for ensuring teacher effectiveness have shaped the landscape of education. In the midst of policy mandates for...  相似文献   
966.
This study examined whether maternal control protects African American adolescents from the negative influence of problem peers. Two forms of control were examined, behavioral control and psychological control. It was hypothesized that there would be a curvilinear relation between control and adolescent problem behavior, with the strength of the relationship and the amount of control optimal for adolescent development varying by the level of peer problem behavior. In general, data supported this model, particularly in regard to behavioral control, where the predicted curvilinear interaction occurred even after controlling for initial levels of problem behavior. The predicted curvilinear interaction between psychological control and peer problem behavior was statistically significant if initial levels of problem behavior were not controlled for but was not significant after controlling for initial problem behavior. These findings suggest that high-quality parenting can play a modest but critical role in the face of environmental adversity.  相似文献   
967.
The study investigates the relationship between memory updating and arithmetic word problem solving. Two groups of 35 fourth graders with high and low memory-updating abilities were selected from a sample of 89 children on the basis of an updating task used by Palladino et al. [Memory & Cognition 29 (2002) 344]. The two groups were required to solve a set of arithmetic word problems and to recall relevant information from another set of problems. Several span tasks, a computation test, and the PMA verbal subtest were also administered. The group with a high memory-updating ability performed better in problem solving, recalling text problems, and in the computation test. The two groups did not differ in the PMA verbal subtest or in the digit and word spans. Results were interpreted as supporting the importance of updating ability in problem solving and of the substantial independence between memory updating and problem solving on one hand and verbal intelligence on the other.  相似文献   
968.
ABSTRACT

This paper examines the content of alphabet books published for Russian-speaking children in Latvia, Estonia and Poland in the 1920s and explains the nexus between socio-cultural context and representation of social environment and children’s interactions to explore strategies of adaptation offered to children. The textbooks were quantified using a target codifier. The results are embedded in the context of theories of intergenerational cultural transmission and integration of minorities. The textbooks published for Russian-speaking children in Poland and Estonia exemplify a classical postfigurative type of intergenerational transmission to ensure group cohesion protecting against assimilation. The model of transmission in alphabet books published in Latvia is based on encouraging a child to establish values and guidelines independently. Thus, Latvian alphabet books allow a child to join a network of tenuous relationships for integration into the dominant culture. Therefore, the study provides a retrospective of strategies of Russian-speaking minorities’ consolidation and integration into dominant societies.  相似文献   
969.
970.
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