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Erich Petushek Chris Richter David Donovan William P. Ebben Phillip B. Watts Randall L. Jensen 《Sports Engineering》2012,15(3):159-166
Quantifying countermovement jump (CMJ) and landing knee flexion angle is important for performance and injury risk assessment. The purpose of the study was to compare electrogoniometer (El-Gon)- and video-derived CMJ and landing knee flexion angle. Twenty-two adults performed three CMJs while knee flexion angle was simultaneously assessed using an El-Gon and video. The average systematic offset (RMSE) of the El-Gon-derived knee flexion angle throughout the entire movement was 7.03°?±?2.69°. Excellent reliability was demonstrated by the El-Gon (ICCavg?=?0.92). Countermovement knee flexion angle, maximum landing knee flexion angle and flexion angle at maximum vertical ground reaction force were 12.0°, 10.9°, and 5.7° higher, respectively, when assessed using El-Gon (p?<?0.001), compared to video. Errors between instruments are likely due to El-Gon crosstalk, misalignment and/or axis determination. The El-Gon is a cost-effective and time-efficient alternative to video analysis for the assessment of knee flexion angle if the error is accounted for and the sensor is precisely attached. 相似文献
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Integration of microfluidic devices with pressure-driven, self-powered fluid flow propulsion methods has provided a very effective solution for on-chip, droplet blood testing applications. However, precise understanding of the physical process governing fluid dynamics in polydimethylsiloxane (PDMS)-based microfluidic devices remains unclear. Here, we propose a pressure-driven diffusion model using Fick''s law and the ideal gas law, the results of which agree well with the experimental fluid dynamics observed in our vacuum pocket-assisted, self-powered microfluidic devices. Notably, this model enables us to precisely tune the flow rate by adjusting two geometrical parameters of the vacuum pocket. By linking the self-powered fluid flow propulsion method to the sedimentation, we also show that direct plasma separation from a drop of whole blood can be achieved using only a simple construction without the need for external power sources, connectors, or a complex operational procedure. Finally, the potential of the vacuum pocket, along with a removable vacuum battery to be integrated with non-PDMS microfluidic devices to drive and control the fluid flow, is demonstrated. 相似文献
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The present study examined frames and second-level agenda-setting attributes used by national and local newspapers to cover the 2012 Aurora, Colorado shootings. Unlike research examining coverage of school shootings, this study examined a mass shooting that did not occur at a school. Both newspaper types published a similar number of articles—though national articles tended to be longer—and virtually stopped coverage after 18 days. While previous coverage tended to focus on shootings’ societal implications, Aurora coverage focused more on individuals involved in the time immediately surrounding the shootings. National papers focused on the gunman, while the local press tended to focus on victims. Mass shootings in general tend to be salient news items, but the present study further shows news outlets may now focus on incidents’ specifics instead of common characteristics they might share, perhaps because audiences have an existing understanding of them. The shootings were framed in terms of gun control; national newspapers used this frame more often than did local newspapers. Both newspaper types tended to discuss gun control as directly related to the Aurora shootings, rather than as a societal or continuing need. Results offer further evidence that second-level agenda-setting and framing are distinct concepts. 相似文献
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Kyle K. Bishop 《Journal of College Counseling》2016,19(3):205-217
The author used an archival study to explore the relationship between college counseling and retention. The cohort for this study was a college's 2006 class of full‐time, 1st‐year students (N = 429). The results of chi‐square analyses and regression analyses indicated (a) a significant difference in retention between high‐risk and low‐risk students who used counseling services (CS) and (b) that a student's risk for dropout did not vary significantly over time based on risk level or CS use. 相似文献
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