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171.
Buccal cell usage has been shown by many to be a cost effective and safe method to isolate DNA for various biological experiments especially large epidemiological studies (Garcia-Closas et al. Cancer Epidemiol Biomarkers Prev 10:687–696, 2001). Non-invasive DNA collection methods are preferred over phlebotomy in order to increase study participation and compliance in research centers and for sick patients in hospital settings. There have been conflicting reports about the methodology and results obtained from using buccal DNA. It is not very clear if phlebotomy can be confidently replaced by buccal cell DNA. It is often left for the user to take an intelligent decision. To address this issue, we compared the performance of buccal and blood DNA from same subjects in a genotyping experiment and this paper reports the results. Cotton swab derived buccal cells were scraped from the inner side of cheeks from 16 subjects, and blood was also drawn from the same 16 subjects participating in a genotypic association study of a lipid disease. The DNA quality was assessed by resolving on agarose gels, checking purity (A260/A280) and finally by microarray hybridization. This study showed that DNA degradation affects the total yield and performance of the buccal DNA when compared to the blood DNA in microarray based genotyping. Genotyping results can be seriously compromised if care is not taken to check the quality and yields of such specimens.  相似文献   
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This study aimed to analyse fatigue-induced changes in mechanical sprinting properties during a specific repeated-sprint test in elite rugby sevens athletes. Twenty elite rugby sevens players performed ten 40?m sprints on a 30?s cycle with participant’s running back and forth in a marked lane. Radar was used to assess maximal overground sprint performance over each 40?m. Macroscopic mechanical properties (maximal horizontal force (F0), maximal horizontal power (Pmax), maximal ratio of horizontal force (RFpeak), decrease in the ratio of horizontal-to-total force (DRF), total force and maximal sprinting velocity (v0)) were drawn from horizontal force velocity relationships, using a validated method applied to the speed–time data. Fatigue-induced changes were analysed comparing the first sprint to an average of 2nd-4th, 5th-7th and 8th-10th. Repeated-sprint ability (RSA) testing induced substantial changes in the maximal velocity component, with a decrease (–15%) in v0 (effect size (ES)?=?–2.46 to –4.98), and to a lower extent (–5.9%) in the maximal force component F0 (ES?=?–0.59). DRF moderately decreased (14%; ES=–0.76–1.11), and RFpeak largely decreased in the later sprints (ES?=?–0.32 to –1.27). Fatigue observed in this RSA test appeared to have a greater effect on the technical ability to produce horizontal force at high velocities, likely due to an alteration in the ability to maintain horizontally oriented force application when velocity increases rather than during the initial acceleration phase, but also the overall force production capacity. The ability to maintain forward-oriented force at high velocities is of central importance for identifying fatigue and monitoring load.  相似文献   
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It is well documented that government agencies, at all levels, continue to have problems ensuring that government web sites follow laws related to web accessibility for people with disabilities. Although there are a number of published studies on government web accessibility that are point-in-time, there are no published studies consisting of a longitudinal analysis of state-level government web site accessibility. This paper contributes to the research literature in three ways: 1) an accessibility inspection of 25 Maryland state government homepages in 2012 which involved 150 human inspections of web pages, 2) a comparison of the results from 2012 to a similar accessibility evaluation in 2009, and 3) a discussion of the role of a web page template, which was introduced in Maryland state government shortly after the 2009 evaluation. The data from this longitudinal evaluation leads to the conclusion that web page templates do tend to result in more accessible sites within state government.  相似文献   
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Lack of motivation, or amotiation, is emerging as a critical issue in high school physical education. The Amotivation Inventory-Physical Education (Shen, Winger, Li, Sun, & Rukavina, 2010) was developed to measure the multidimensional nature of amotivation construct in physical education. This study was designed to examine the consistency of the metric properties of Amotivation Inventory-Physical Education scores by evaluating their factorial structure for invariance across gender in a sample of 985 urban inner-city high school adolescents. Latent mean invariance was also tested. Results revealed that constraining factor loadings and intercepts in sequential configural, metric, and scalar invariances had no meaningful impact on model fit. However, gender might play a role in the magnitude of factor scores. Findings suggest that the four-factor structure of the Amotivation Inventory-Physical Education is a satisfactory representation of motivational deficits for urban inner-city adolescents and provide significant validity evidence for the scale scores in urban high school settings.  相似文献   
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The present study tested the hypothesis that maturing prefrontal lobes play a role in the development of proportional reasoning skill because the prefrontal lobes are involved in the inhibition of task‐irrelevant information and the representation of task‐relevant information. The hypothesis that reasoning development is in part dependent upon physical experience was also tested. Students (all males) who failed to solve a diagnostic proportions task were administered several tests of prefrontal lobe functions. The students were then randomly assigned to manipulative or verbal tutoring groups. Both groups received a series of individual testing, tutoring and testing sessions on proportional reasoning. As predicted, performance on the prefrontal lobe tasks (measures of inhibiting ability, planning ability, dissembedding ability, and working memory capacity) significantly predicted performance on proportional reasoning tasks following tutoring. Students' computational skills were not a significant predictor. Also, the manipulative group's proportional reasoning performance was significantly higher than that of the verbal tutoring group. Therefore, the present results provide support for the hypothesis that maturing prefrontal lobes and physical experience play roles in the development of proportional reasoning skill. © 2000 John Wiley & Sons, Inc. J Res Sci Teach 37: 1171–1182, 2000  相似文献   
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