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961.
We describe the results of electromigration desalination of two soluble salt-contaminated Galician granites. The efficacy of electromigration, which had not been previously applied to granite, was assessed for two types of granite contaminated with a 20% NaCl solution and seawater. Desalination effectiveness was evaluated as follows: (1) analysis of anode and cathode ion content during testing; (2) analysis of ions at different distances from the electrodes after testing; (3) pH assessment of the stone surfaces; and (4) evaluation of colour changes. Results were very satisfactory; by the end of testing, chloride was reduced by almost 100% in both the NaCl and seawater contaminated samples. Sulfate reduction was also significant, despite this ion's lower mobility. The granite pH values remained close to neutral and colour changes were minimal. The difference in effectiveness of the process for the two types of stone was associated with their dissimilar pore structure.  相似文献   
962.
Mechanical properties of wood at different length scales of its hierarchical structure are governed by structural and compositional properties on smaller length scales. This opens up the possibility to use microstructural data for estimating mechanical properties, which are difficult to assess by conventional, destructive testing but are nevertheless of high relevance for conservation practice. Herein, we investigate such microstructure-mechanics relationships for a particular example, namely the load bearing archaeological oak of the Oseberg Viking ship, displayed at the Viking Ship Museum in Oslo, Norway. In order to identify the effects of degradation on the mechanical behavior and their relations to the microstructure, recent oak specimens of different geographical origin (Norway and Austria) are investigated as well. Wood exhibits a cellular structure. Its cell walls are composed of an amorphous polymer matrix consisting of lignin and hemicelluloses and embedded, stiff cellulose fibers. At the cell level, experimental studies comprised microscopic investigations of the cellular structure, chemical analyses of the composition of the cell walls, as well as nanoindentation tests on single cell walls. The same samples were also analyzed on the macroscopic level, where additionally mass density and annual ring data were measured together with ultrasonic stiffnesses. The chemical data clearly indicate deterioration in the archaeological oak, affecting mainly hemicelluloses and amorphous cellulose. At the cell wall scale, however, this does not necessarily lead to a weaker material behavior. The nanoindentation modulus, as a measure of the cell wall stiffness, was found to even increase. This is counterintuitive to our understanding of the effects of chemical degradation. It might be due to possible modification of lignin in the Oseberg oak, and thus have a stronger effect on the indentation modulus than the concurrent weakening of the interfaces between the load-carrying cellulose fibers and the connecting cell wall matrix when analyzing wood at the microscopic level. A similar effect is also observed for the transversal stiffness of macroscopic samples, which increases. In tension-dominated loading modes, however, the degradation of the interfaces is the dominant effect, resulting for example in a considerable reduction of the macroscopic stiffness in longitudinal direction. This underlines the utmost relevance of the loading condition on the remaining load-carrying capacity of degraded wood. On the macroscale, effects of the geographical origin (i.e. growth conditions) on ring characteristics of the oak tissues override the effects of degradation on the mechanical behavior. They have to be carefully extracted in order to come up with conclusions on the effect of degradation from macroscopic test results. The identified microstructure-mechanics relationships provide the basis for–in further research steps–building mathematical models describing the relations between microstructural characteristics and macroscopic mechanical properties and, thereon, for structural analyses of historical wooden objects.  相似文献   
963.
964.
This article presents an empirical reflection on how the prototyping of an environmental enrichment device for chimpanzees at the National Zoo of Chile precipitates a cosmopolitical encounter. Using material produced by design students, zookeepers and the chimps Judy and Gombe, we describe how prototyping iterations establish open processes of dialogue and encounters among humans and nonhumans. The case will demonstrate how prototyping can go further than the generation of models of an original. On the contrary, the cosmopolitical encounter emerging from the prototyping process makes evident a truly ontological vocation, acknowledging humans and other-than-human beings as singular entities. Its provisional and malleable nature turns this device into a privileged locus for the exploration of interspecies entanglement. Although zoos are scientifically organized institutions, in this case we observe how its anthropocentric hierarchy was performatively reshuffled at certain moments of the prototyping process. The cosmopolitical qualities of the prototyping process analyzed derive from its capacity to deploy an ethics of attention and care between the agencies at play, that is, for unfold gestures of mutual vulnerability. Finally, we propose prototyping as a device for moving from cosmopolitics as a way of understanding the world to cosmopolitics as a matter of design.  相似文献   
965.
966.
The literature on Cultural Economics provides us with some examples for the measurement of technical efficiency. However, there are few case studies dedicated to the analysis of allocative efficiency. The aim of this paper is to fill this gap by incorporating a methodology that analyses both technical and allocative efficiency. We use the Shephard’s distance function, particularly suitable when affronted with non-profit-making firms or institutions that are not interested in cost minimization. As an empirical application, we analyse the efficiency of Fundación Princesa de Asturias (PAF), a Spanish non-governmental organization devoted to promoting the cultural, scientific and humanistic values of universal heritage, the period of study being 1988–2012. Our findings suggest that PAF could have used 7% less inputs to achieve the same level of output. On the other hand, we have found allocative inefficiency. Concretely, the input for other expenditures appears to have been over-utilized in relation to both the inputs for labour and current assets, with labour in turn being over-utilized in relation to current assets. Moreover, our results indicate that both technical and allocative efficiency have clearly improved during the period analysed. In summary, our empirical application shows how distance function methodology can be successfully implemented to measure allocative efficiency in cultural firms and institutions.  相似文献   
967.
This paper analyzes the effects that the 2012 VAT rise in Spain had on household’ demand for cultural goods and services. Household’ demands are modeled as a two-stage QUAIDS. After estimating price and expenditure elasticities, and the pass-through parameter associated with the reform, our results show that the individual welfare loss and the increment in the tax bill increase, but less than proportionately, with income. Consequently, the reform can be considered as regressive. Relating the effects of the VAT reform to households’ incomes also implies a low quantitative effect, because of the low proportion of total household expenditure that cultural expenditure represents. From a social perspective, the size of the induced welfare loss would positively depend on society’s inequality aversion. Regardless of the latter, it cannot be concluded whether the reform would have increased or reduced inequality in the distribution of cultural spending. Our results prove qualitatively robust to alternative values of the pass-through parameter.  相似文献   
968.
The Spring Fiestas in Seville (Spain) (SFS) are the most important cultural events in the city each year. The present paper pursues two aims. The first is to characterize the SFS as a new prototype of a complex cultural good that expresses the link between the people and the place in which they live based on material and immaterial cultural heritage represented through popular celebrations. The second goal is to conduct an empirical analysis of the determinants that shape attendance intensity by estimating a zero-truncated count data model using a unique dataset of attendees at the SFS in 2009. Findings indicate that attendance is strongly associated with variables reflecting knowledge, institutional links, past experiences, and the perceived external benefits generated by the existence of the SFS. The article contributes to the literature by exploring participation in popular celebrations, a field of inquiry that to date is extremely limited in cultural economics.  相似文献   
969.
The widely supported wish for more inclusive education places ever greater expectations on teachers’ abilities to teach all children, including those with special needs and challenging behaviours. The present study aimed at the question whether teachers judge pupil behaviour more negatively if there are more children with difficult behaviour in class. The teachers of 184 classes in 31 regular primary schools were asked to complete the Strength and Difficulties Questionnaire (SDQ-L) for 3649 pupils. Six linear mixed models were carried out with as independent variable the number of pupils that teachers perceived to have ‘abnormal behaviour’, and the class mean without these pupils as the dependent variable. For all SDQ-L subscales – emotional problems, behavioural problems, problems with hyperactivity, problems with peers, poor prosocial behaviour and total problems – the number of pupils perceived as problematic was associated with less favourable teacher perceptions of the rest of the class. The results of this study are a plea for a contextual perspective on pupil behaviour in class, both where teachers are asked to report on individual pupils, as well as where interventions are done on emotional and behavioural problems in class.  相似文献   
970.
ABSTRACT

We performed a randomized, controlled trial to analyse the effects of resistance training (RT) on cognitive and physical function among older adults. Fifty participants (mean age 67 years, ~60% woman) were randomly assigned to an RT program or a control group. Participants allocated to RT performed three sets of 10-15RM in nine exercises, three times per week, for 12-weeks. Control group did not perform any exercise. Variables included cognitive (global and executive function) and physical function (gait, mobility and strength) outcomes. At completion of the intervention, RT was shown to have significantly mitigated the drop in selective attention and conflict resolution performance (Stroop test: -494.6; 95%CI: -883.1; ?106.1) and promoted a significant improvement in working memory (digit span forward: -0.6; 95%CI: ?1.0; ?0.1 and forward minus backward: -0.9; 95% CI: ?1.6; ?0.2) and verbal fluency (animal naming: +1.4, 95%CI 0.3, 2.5). No significant between-group differences were observed for other cognitive outcomes. Regarding physical function, at completion of the intervention, the RT group demonstrated improved fast-pace gait performance (?0.3; 95% CI: ?0.6; ?0.0) and 1-RM (+21.4 kg; 95%CI: 16.6; 26.2). No significant between-group differences were observed for other mobility-related outcomes. In conclusion, RT improves cognitive and physical function of older adults.  相似文献   
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