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ABSTRACTThe 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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V. J. Hinton D. C. De Vivo R. Fee E. Goldstein Y. Stern 《Learning disabilities research & practice》2004,19(3):146-154
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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采用斯皮尔伯格状态-特质焦虑量表、问卷调查中国甲A足球和CBA联赛教练，揭示职业教练竞赛焦虑现状和特点。研究结果表明：(1)职业教练竞赛焦虑包含特质焦虑和状态焦虑两方面，联赛期与歇赛期相比，特质焦虑相对恒定，无明显差异，而状态焦虑水平呈高度显著性差异；(2)联赛期主教练焦虑程度明显高于助理教练，且特质焦虑和状态焦虑差异均呈显著性；(3)联赛期不同阶段、不同处境主教练状态焦虑值随联赛进程呈不同的变化曲线，且与球队成绩排名直接相关。 相似文献
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