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821.
Radiation dose monitoring has become an essential service that hospitals must perform. Depending on the system in place, this can result in the collection of large quantities of data, ripe for analysis. These data should include a wide variety of variables for each study because assessment of the propriety of the patient’s dose is dependent on many factors, including patient age and size, as well as the body section that is being scanned. Moreover, the scanners themselves have many properties that affect patient dose, such as model, pitch and kVp. In this paper, we propose an engine that seamlessly integrated with a clinical PACS to retrieve radiation dosage data. We devised several schemes to analyze these data through visualization and mining techniques that examine it at different scopes. We demonstrate the utility of such visual methods at examining large, noisy, and multi-dimensional data, which is embodied in the collected radiation data.  相似文献   
822.
ABSTRACT

We analysed the time course of recovery of creatine kinase (CK) and countermovement jump (CMJ) parameters after a football match, and correlations between changes in these variables and match time–motion parameters (GPS-accelerometry) in 15 U-19 elite male players. Plasma CK and CMJ height (CMJH), average concentric force (CMJCON) and average eccentric force (CMJECC) were assessed 2 h before and 30 min, 24 h and 48 h post-match. There were substantially higher CK levels 30 min, 24 h and 48 h (ES: 0.43, 0.62, 0.40, respectively), post-match. CMJECC (ES: ?0.38), CMJH (ES: ?0.35) decreased 30 min post, CMJCON (ES: ?0.35), CMJECC (ES: ?0.35) and CMJH (ES: ?1.35) decreased 24 h post, and CMJCON (ES: ?0.41) and CMJH (ES: ?0.53) decreased 48 h post. We found correlations between distance covered at velocities ≤21 km · h?1 and changes in CK at 24 h (r = 0.56) and at 48 h (r = 0.54) and correlations between CK and distance covered >14 km · h?1 (r = 0.50), accelerations (r = 0.48), and decelerations (r = 0.58) at 48 h. Changes in CMJCON 30 min and 24 h post (both r = ?0.68) correlated with impacts >7.1·G. Decelerations >2 m · s?2 correlated with changes CMJCON (r = ?0.49) at 48 h and CMJECC (r = ?0.47) at 30 min. Our results suggest that match GPS-accelerometry parameters may predict muscle damage and changes in components of neuromuscular performance immediately and 24–48 h post-match.  相似文献   
823.
Abstract

Salvador López Gómez was a great exponent of gymnastics in Spain in the nineteenth and the twentieth century. His role as a teacher, a writer and even as a law developer who promoted gymnastics deserves a detailed study. For that reason, through primary sources of this era and, specially, papers from López Gómez himself, this paper depicts his long professional career, his conception of gymnastics and the constant efforts, not always properly rewarded, that he made for its social respect and acknowledgement during that time.  相似文献   
824.
This study investigated interpersonal coordination tendencies in 1vs.1 dyads in rugby union, here expressed by participants' movement velocity towards or away from the sideline as they competed to score or prevent a try. We examined whether coupling tendencies of members of each dyad shaped key performance outcomes (try or successful tackle). Data on movement displacement trajectories of eight male rugby union players (aged 11–12 years) were analysed during performance in 47 trials. To assess coordination tendencies during exploratory behaviours in the dyads, analyses of performance time series data were undertaken using variable time graphs, running correlations and cross-correlations. Results revealed distinct coupling patterns characterised by shifts between synchronous coordination and asynchronous coordination tendencies and uncoordinated actions. Observed behaviours were interpreted as attempts of competing participants to create and perceive possibilities for action while seeking to achieve specific performance goals. Findings also revealed that a variety of patterned relations between participants resulted in different performance outcomes.  相似文献   
825.
Lack of physical activity (PA) and high levels of sedentary behaviour (SB) have been associated with health problems. This systematic review evaluates the effectiveness of school-based interventions to increase PA and decrease SB among 15–19-year-old adolescents, and examines whether intervention characteristics (intervention length, delivery mode and intervention provider) and intervention content (i.e. behaviour change techniques, BCTs) are related to intervention effectiveness. A systematic search of randomised or cluster randomised controlled trials with outcome measures of PA and/or SB rendered 10 results. Risk of bias was assessed using the Cochrane risk of bias tool. Intervention content was coded using Behaviour Change Technique Taxonomy v1. Seven out of 10 studies reported significant increases in PA. Effects were generally small and short-term (Cohen's d ranged from 0.132 to 0.659). Two out of four studies that measured SB reported significant reductions in SB. Interventions that increased PA included a higher number of BCTs, specific BCTs (e.g., goal setting, action planning and self-monitoring), and were delivered by research staff. Intervention length and mode of delivery were unrelated to effectiveness. More studies are needed that evaluate long-term intervention effectiveness and target SBs among older adolescents.  相似文献   
826.
This poster presents the results of an investigation carried out to assess the different possibilities that a discipline belonging to the field of social psychology, and defined by the social representation of the subject and thus different from the conservation/restoration field, could contribute to the study of the relationships between those involved in the production and preservation of contemporary art, the artist and the conservator-restorer.  相似文献   
827.
When dealing with contemporary art, conservators have to address not only the material aspects of the artwork but also other highly complex issues. The Argentinian artist Leon Ferrari is a representative example. He created avant-garde art installations but also worked with traditional techniques. His works raise dilemmas over concepts such as authorship, authenticity, legitimacy of art. Some of his artworks only interested him as a means to express his opinions and he was not concerned about alterations in their appearance. Therefore, what should be kept in them is not in an area of certainty for conservators. An essential key for achieving a responsible and respectful conservation result, is to understand the ideology involved in each ‘art piece’ created by Ferrari.  相似文献   
828.
The aim of this study was to explore the intersection between Medium Theory (MT) and Third-Person Effect (TPE) and evaluate how the research on MT can further our knowledge of the TPE. The study has proven that the perceptual hypothesis of the TPE is confirmed in different media contents and across media types (TV and the Internet) and that media type has an impact on the magnitude of the TPE. In addition, media type can also be a requisite for TPE to occur. On the other hand, the study shows that media type can have an influence on people’s support to restrict controversial content, in particular, pornography.  相似文献   
829.
830.
The value of sport as a vehicle for social development and progressive social change has been much debated, yet what tends to get missed in this debate is the way education may foster, enable or impede the transformative action that underpins the social outcomes to which the ‘sport for development and peace’ (SDP) sector aspires. This article draws on the critical pedagogy of Paulo Freire and his contemporaries to examine the nature of transformative action and how it may be fostered within SDP programs. Insights from critical pedagogy are applied to, and illustrated through, qualitative research undertaken with SDP programs located in Cameroon and Kenya. The findings show the complexities of designing and implementing critical pedagogy in a SDP context and, in particular, the challenges of creating and mobilizing for transformative action. Opportunities and lessons for embedding critical pedagogy within SDP programs are also presented.  相似文献   
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