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Substitution of slate roofing tiles is a conventional operation during building restoration, since tiles are very difficult to restore or clean because of the high degree of alteration they suffer. Criteria for replacement of historical building stones must be based on geological, geotechnical and esthetic parameters, among which color is of great importance. In this sense, this paper constitutes a comprehensive and useful colorimetric study of roofing slates from the Iberian Peninsula, for the purposes of restoration. The color of 50 commercial varieties of roofing slate mined in quarries from the 12 mining districts in the Iberian Peninsula was analyzed with a spectrophotometer device, by considering the CIELAB color space. The results of the study were used to develop a protocol for characterizing the color of roofing slate and to define the color range of roofing slate from the Iberian Peninsula. In addition, the similarities and differences in the color and microstructure of the different commercial varieties of Iberian roofing slate were established and the limit of acceptability of replacement of one type of slate by another was determined. Parameter hab was found to be the most important CIELAB color coordinate as regards the formation of homogeneous color groups, and the specular component excluded (SCE) mode was most sensitive as regards detecting color differences between two samples.  相似文献   
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The aim of this study was to quantify the type of offensive sequences that result in goals in elite futsal. Thirty competitive games in the Spanish Primera Division de Sala were analysed using computerised notation analysis for patterns of play that resulted in goals. More goals were scored in positional attack (42%) and from set pieces (27%) compared to other activities. The number of defence to offense “transitions” (= 45) and the start of offensive plays due to the rules of the game (= 45) were the most common type of sequences that resulted in goals compared to other patterns of play. The central offensive zonal areas were the most common for shots on goal, with 73% of all goals scored from these areas of the pitch compared to defensive and wide zones. The foot was the main part of the body involved in scoring (= 114). T-pattern analysis of offensive sequences revealed regular patterns of play, which are common in goal scoring opportunities in futsal and are typical movement patterns in this sport. The data demonstrate common offensive sequences and movement patterns related to goals in elite futsal and this could provide important information for the development of physical and technical training drills that replicate important game situations.  相似文献   
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Abstract

The Olympic Games of the modern era are powerful global mediated events. Olympic cities receive an overwhelming examination by world media. As the 2016 Olympic host, Rio de Janeiro has been given an enormous amount of attention, both by the international media and researchers who looked at the urban spaces of Rio, the struggles over the hegemony of the city and the social meanings the Olympics bring to the host city’s citizens. However, studies over the historical relationship between Rio, sport and media are rare. This paper addresses the historical uses of the term Olympic by Brazilian media during the late nineteenth and the early twentieth centuries. By looking at the main articles in the newspapers of these periods, we examine the extent to which ideologies over sports have changed the way the Olympics were represented in Brazil’s national imaginary. We demonstrate how the use of expressions associated with the Olympics historically generated a closer appreciation of these events by the public. We also show how political authorities appropriated the Olympics for their own benefit. The paper concludes by asking whether or not the historical lessons from the early Olympic ideas in Brazil have been learned by the 2016 Rio Games organizers.  相似文献   
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The protective action of remote ischaemic preconditioning (RIPC) has been demonstrated in the context of surgical interventions in cardiology. Application of RIPC to sports performance has been proposed, but its effect on the electrocardiogram (ECG) during exercise remains unknown. This exploratory study aims to measure the changes in ventricular repolarization observed during exercise following RIPC in healthy subjects. In an experimental randomized crossover study, 17 subjects underwent two bouts of constant load exercise tests at 75% and 115% of gas exchange threshold (GET). Prior to exercise, they were allocated to either control or RIPC intervention with four cycles of 5?min of ischaemia followed by 5?min of reperfusion. ECG was continuously recorded during the protocol. QT and RR intervals were measured every 30?s (on an average tracing of the preceding 10?s). Although the time course of RR intervals did not differ between the two interventions (p?=?.56 at 75% GET and p?=?.74 at 115% GET), a significant shortening of QT intervals (measured from Q onset to T end) was observed during exercise (mean?±?standard deviation of RIPC vs. control: ?32?±?19?ms at 75% GET (p?p?p?p?相似文献   
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The purpose of this study is to explore key factors that impact the college transition of aspiring underrepresented minority students in the biomedical and behavioral sciences, in comparison with White, Asian students and non-science minority students. We examined successful management of the academic environment and sense of belonging during the first college year. Longitudinal data were derived from the Higher Education Research Institute’s (HERI) 2004 Cooperative Institutional Research Program (CIRP) Freshman Survey and the 2005 Your First College Year (YFCY) Survey. Using a reformulation of the integration model (Nora, Barlow, and Crisp, 2005), we find concerns about college financing, negotiating family support and responsibility, and campus racial dynamics (perceived and behavioral) affect student adjustment and sense of integration in the first year. This study was made possible by the support of the National Institute of General Medical Sciences, NIH Grant Number 1 RO1 GMO71968-01. This independent research and the views expressed here do not indicate endorsement by the sponsor.  相似文献   
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To what extent do students and teachers hold similar beliefs about excellent teaching? Do differences in beliefs have practical implications (e.g., how students rate their teachers on end-of-semester evaluation forms)? In Study 1, undergraduate students (N=414) and faculty members (N=128) responded to questionnaires assessing their perceptions of an excellent discussion leader, lecturer, or instructor. Participants judged items that contributed to a Structure composite as more characteristic of excellent lecturers than excellent discussion leaders and items that contributed to a Process composite as more characteristic of excellent discussion leaders than excellent lecturers. Results for students and teachers showed several systematic differences. In Study 2,278 students and their course teachers rated the characteristics of a hypothetical excellent lecturer. In addition, students rated the effectiveness of their individual teachers. Students’ ratings of their teachers were higher when students and teachers agreed on their perceptions of characteristics of excellent lecturers.  相似文献   
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