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ABSTRACT

The preservation of artefacts in museum collections is profoundly affected by fluctuations in temperature and, especially, relative humidity (RH). Since the late nineteenth century, many studies have been carried out on the best way to control hygrothermal conditions. In old buildings located in maritime temperate climate zones (such as Portugal) with strong thermal inertia, and which have low ventilation rate (relative to the volume and number of visitors), daily and seasonal hygroscopic inertia may help to assure the maintenance of RH stabilization conditions. The use of expensive active systems may be minimized through the passive behaviour of internal finishing building materials. This work presents the results of an experimental laboratory study conducted in a flow chamber to demonstrate the enormous potential of hygroscopic materials in stabilizing interior relative humidity. Based in these results and in-situ monitoring in a museum housed in a building, located in Porto, with a typical construction of the 1950s (granite masonry and reinforced concrete slabs), a numerical analysis was done to quantify the influence of hygroscopic materials in stabilizing the interior relative humidity.  相似文献   
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This paper addresses the need to recognize the importance, and the challenges, of preserving the hugely expanding record of medicine today for historians of the future. We are faced not only with an increase in traditional publishing formats, but also with the rapid growth in electronic communications. Two celebrated medical cases, one from the late seventeenth century and one from the late twentieth, are used to illustrate the differences and the difficulties. The need for active and effective professional collaboration is stressed; libraries should work together to address these issues.  相似文献   
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Duchenne Muscular Dystrophy (DMD) is a neurogenetic developmental disorder that presents with progressive muscular weakness. It is caused by a mutation in a gene that results in the absence of specific products that normally localize to muscle cells and the central nervous system (CNS). The majority of affected individuals have IQs within the normal range, generally with lower verbal than performance IQ scores. Prior work has demonstrated selective deficits on tests of verbal span and immediate memory. For the current study, 26 boys with DMD (and normal intellectual function) and their unaffected siblings were evaluated. Paired comparisons demonstrated that the children with DMD had significantly poorer academic achievement scores than their siblings, even though their vocabulary levels and home and educational environments were comparable. Children with DMD also had more behavioral concerns, physical disabilities, and poorer verbal memory spans. Linear regression indicated that behavioral concerns, executive function, and physical disability did not contribute substantially to academic performance, whereas performance on verbal span did. DMD presents with a selective developmental aberration in verbal span that has wide‐ranging consequences on learning skills.  相似文献   
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The authors report on a self‐completed questionnaire study from a North Yorkshire based general practice regarding the information needs of its clinicians. The work was carried out with a particular focus on the practice library, and the findings identified that a new approach to maintaining and developing the library was needed. The literature regarding the information needs of primary care clinicians and the role of practice libraries is considered, and compared to those of the clinicians at the practice. Discussion follows on how a collaborative project was set up between the practice and a librarian based at the local NHS Trust library in order to improve the existing practice library. Difficulties encountered and issues unique to the project are explored, including training implications presented by the implementation of electronic resources. Marketing activities implemented are discussed, how the library will operate in its new capacity, and how ongoing support and maintenance of the library will be carried out. It is concluded that although scepticism still exists regarding librarian involvement in practice libraries, collaboration between clinicians and librarians is an effective approach to the successful development and maintenance of a practice library, and recommendations are therefore made for similar collaborative work.  相似文献   
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The purpose of this article was to revitalize and disentangle common misconceptions about a scientific agenda for clinical supervision.  相似文献   
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