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971.
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
972.
973.
Maria P. M. Santos Cassiano R. Rech Claudia O. Alberico Rogério C. Fermino Ana P. Rios João David 《Measurement in physical education and exercise science》2016,20(2):93-98
The app for the System for Observing Play and Recreation in Communities (iSOPARC®) was developed to enhance System for Observing Play and Recreation in Communities data collection and management. The study aim was to examine the usability and inter-rater reliability of iSOPARC®. Trained observers collected data in 16 park areas in two Latin America cities (Curitiba, Brazil; Bogotá, Colombia) using both the original System for Observing Play and Recreation in Communities (mechanical counter) and new iSOPARC® (electronic counter) methods. A total of 8,707 park users (3,958 females and 4,749 males) were observed. Reliabilities among observers were determined using the intraclass correlation coefficient and relative overall agreement (%) in three ways: (a) mechanical versus mechanical, (b) mechanical versus electronic, and (c) electronic versus electronic. When both used mechanical counters comparisons overall agreement was over 78% (intraclass correlation coefficient = .982; p < .001) for variables in all analysis. When one used a mechanical counter and the other used electronic (iSOPARC®) comparisons overall agreement was higher for age (84%; p < .001) than for physical activity (83%; p < .001) variables and average intraclass correlation coefficient was .965. Using both used iSOPARC® comparisons overall agreement was 81% to physical activity and 83% to age group. Results suggest iSOPARC® can be used reliably for examining variables previously validated in System for Observing Play and Recreation in Communities. 相似文献
974.
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
975.
Felipe García-Pinillos Alejandro Molina-Molina Pedro Á. Latorre-Román 《Sports biomechanics / International Society of Biomechanics in Sports》2016,15(2):103-115
This study aimed to determine whether kinematic data during countermovement jump (CMJ) might explain post-activation potentiation (PAP) phenomenon after an exhausting running test. Thirty-three trained endurance runners performed the Léger Test; an incremental test which consists of continuous running between two lines 20 m apart. CMJ performance was determined before (pre-test) and immediately after the protocol (post-test). Sagittal plane, video of CMJs was recorded and kinematic data were obtained throughout 2-Dimensional analysis. In addition to the duration of eccentric and concentric phases of CMJ, hip, knee and ankle angles were measured at four key points during CMJ: the lowest position of the squat, take-off, landing, and at the lowest position after landing. Additionally, heart rate was monitored, and rate of perceived exertion was recorded at post-test. Analysis of variance revealed a significant improvement in CMJ (p = 0.002) at post-test. Cluster analysis grouped according to whether PAP was experienced (responders group: RG, n = 25) or not (non-responders group: NRG, n = 8) relative to CMJ change from rest to post-test. RG significantly improved (p < 0.001) the performance in CMJ, whereas NRG remained unchanged. Kinematic data did not show significant differences between RG and NRG. Thus, the data suggest that jumping kinematic does not provide the necessary information to explain PAP phenomenon after intensive running exercises in endurance athletes. 相似文献
976.
977.
Markéta ?kereňová Veronika Mikulová Otakar ?apoun Tomá? Zima 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2016,26(1):103-113
Introduction
Nowadays, on-a-chip capillary electrophoresis is a routine method for the detection of PCR fragments. The Agilent 2100 Bioanalyzer was one of the first commercial devices in this field. Our project was designed to study the characteristics of Agilent DNA 1000 kit in PCR fragment analysis as a part of circulating tumour cell (CTC) detection technique. Despite the common use of this kit a complex analysis of the results from a long-term project is still missing.Materials and methods
A commercially available Agilent DNA 1000 kit was used as a final step in the CTC detection (AdnaTest) for the determination of the presence of PCR fragments generated by Multiplex PCR. Data from 30 prostate cancer patients obtained during two years of research were analyzed to determine the trueness and precision of the PCR fragment size determination. Additional experiments were performed to demonstrate the precision (repeatability, reproducibility) and robustness of PCR fragment concentration determination.Results
The trueness and precision of the size determination was below 3% and 2% respectively. The repeatability of the concentration determination was below 15%. The difference in concentration determination increases when Multiplex-PCR/storage step is added between the two measurements of one sample.Conclusions
The characteristics established in our study are in concordance with the manufacturer’s specifications established for a ladder as a sample. However, the concentration determination may vary depending on chip preparation, sample storage and concentration. The 15% variation of concentration determination repeatability was shown to be partly proportional and can be suppressed by proper normalization.Key words: lab-on-a-chip devices, capillary electrophoresis, multiplex PCR, circulating tumour cells, Agilent DNA 1000 kit 相似文献978.
I. Setuain J. Martinikorena M. Gonzalez-Izal A. Martinez-Ramirez M. Gómez J. Alfaro-Adrián 《Journal of sports sciences》2016,34(9):843-851
Progress in micro-electromechanical systems has turned inertial sensor units (IUs) into a suitable tool for vertical jumping evaluation. In total, 9 men and 8 women were recruited for this study. Three types of vertical jumping tests were evaluated in order to determine if the data provided by an IU placed at the lumbar spine could reliably assess jumping biomechanics and to examine the validity of the IU compared with force plate platform recordings. Robust correlation levels of the IU-based jumping biomechanical evaluation with respect to the force plate across the entire analysed jumping battery were found. In this sense, significant and extremely large correlations were found when raw data of both IU and force plate-derived normalised force–time curves were compared. Furthermore, significant and mainly moderate correlation levels were also found between both instruments when isolated resultant forces’ peak values of predefined jumping phases of each manoeuvre were analysed. However, Bland and Altman graphical representation demonstrated a systematic error in the distribution of the data points within the mean ±1.96 SD intervals. Using IUs, several biomechanical variables such as the resultant force–time curve patterns of the three different vertical jumps analysed were reliably measured. 相似文献
979.
Carmen Gutiérrez-Cruz F. Javier Rojas Marcos Gutiérrez-Davila 《Journal of sports sciences》2016,34(7):651-657
The aim of this study was to analyse the effect of stimulus change timing on reaction response time parameters, horizontal velocity of the centre of mass (CM) and precision during offensive actions in fencing. Twelve fencers from the Spanish National Foil Team were included in the study. Two 500 Hz force plates were used to register the horizontal component of the reaction force while a 3D video camera set at 250 Hz recorded the spatial position of 11 body markers and a projector connected to a programmed stopwatch projected a moving target (stimulus) on a screen. When the circle (target) appeared in the centre of the plastron, fencers had to execute a step-forward-lunge as fast as possible, trying to touch the circle with the tip of the foil. During the lunge, the position of the target could randomly shift or not to three different positions. The stimulus change was performed randomly at four different times with a progressive delay. The results show that target changes did not have any effect when they occurred at the beginning of the movement sequence. However, when the target change was delayed, reaction and movement times increased and the technical execution of the lunge changed, leading to more errors. 相似文献
980.
Filipe Conceição Juvenal Fernandes Martin Lewis Juan José Gonzaléz-Badillo Pedro Jimenéz-Reyes 《Journal of sports sciences》2016,34(12):1099-1106
The purpose of this study was to investigate the relationship between movement velocity and relative load in three lower limbs exercises commonly used to develop strength: leg press, full squat and half squat. The percentage of one repetition maximum (%1RM) has typically been used as the main parameter to control resistance training; however, more recent research has proposed movement velocity as an alternative. Fifteen participants performed a load progression with a range of loads until they reached their 1RM. Maximum instantaneous velocity (Vmax) and mean propulsive velocity (MPV) of the knee extension phase of each exercise were assessed. For all exercises, a strong relationship between Vmax and the %1RM was found: leg press (r2adj = 0.96; 95% CI for slope is [?0.0244, ?0.0258], P < 0.0001), full squat (r2adj = 0.94; 95% CI for slope is [?0.0144, ?0.0139], P < 0.0001) and half squat (r2adj = 0.97; 95% CI for slope is [?0.0135, ?0.00143], P < 0.0001); for MPV, leg press (r2adj = 0.96; 95% CI for slope is [?0.0169, ?0.0175], P < 0.0001, full squat (r2adj = 0.95; 95% CI for slope is [?0.0136, ?0.0128], P < 0.0001) and half squat (r2adj = 0.96; 95% CI for slope is [?0.0116, 0.0124], P < 0.0001). The 1RM was attained with a MPV and Vmax of 0.21 ± 0.06 m s?1 and 0.63 ± 0.15 m s?1, 0.29 ± 0.05 m s?1 and 0.89 ± 0.17 m s?1, 0.33 ± 0.05 m s?1 and 0.95 ± 0.13 m s?1 for leg press, full squat and half squat, respectively. Results indicate that it is possible to determine an exercise-specific %1RM by measuring movement velocity for that exercise. 相似文献