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This research examined varying levels of physical activity and psychomotor and physiological function in variously active older men. Very active moderately active, and low active participants were tested on simple (SRT) and choice reaction time (CRT), coincidence-anticipation timing (CAT), and VO2max. No significant differences for age or height were found, although percentage of fat, and weight were statistically different. Active groups were leaner and lighter. VO2max was significantly different between groups, as physically active groups yielded geater values. SRT and CAT also yielded significantly different results with more active participants showing better performance. No between-groups significant differences resulted for CRT. Generally, increased levels of physical activity were related to superior physiological outcomes and improved psychomotor peformance.  相似文献   
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Published evaluations of career preparation of alumni from long-standing postdoctoral fellowship programs in the biomedical sciences are limited and often focus on quantitative analysis of data from extant publicly available sources. Qualitative methods provide the opportunity to gather robust information about specific program elements from structured postdoctoral training programs and the influence of this training on subsequent career paths of alumni. In-depth interviews with a subset of the National Cancer Institute’s Cancer Prevention Fellowship Program (CPFP) alumni (n = 27), representing more than 25 years of the program’s history and multiple career sectors, were conducted to assess alumni reflections on the training environment and career preparation during their time in the CPFP. NVivo software was used to analyze data and identify major themes. Four main themes emerged from these interviews, including: the value of structured training curriculum, mentorship, transdisciplinary environment, and professional identity. Even when reflecting on training that occurred one to two decades earlier, alumni were able to highlight specific components of a structured postdoctoral training program as influencing their research and career trajectories. These results may have relevance for those interested in assessing how postdoctoral training can influence fellows throughout their careers and understanding salient features of structured programs.  相似文献   
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Amplification of multiple unique genetic targets using the polymerase chain reaction (PCR) is commonly required in molecular biology laboratories. Such reactions are typically performed either serially or by multiplex PCR. Serial reactions are time consuming, and multiplex PCR, while powerful and widely used, can be prone to amplification bias, PCR drift, and primer-primer interactions. We present a new thermocycling method, termed thermal multiplexing, in which a single heat source is uniformly distributed and selectively modulated for independent temperature control of an array of PCR reactions. Thermal multiplexing allows amplification of multiple targets simultaneously—each reaction segregated and performed at optimal conditions. We demonstrate the method using a microfluidic system consisting of an infrared laser thermocycler, a polymer microchip featuring 1 μl, oil-encapsulated reactions, and closed-loop pulse-width modulation control. Heat transfer modeling is used to characterize thermal performance limitations of the system. We validate the model and perform two reactions simultaneously with widely varying annealing temperatures (48 °C and 68 °C), demonstrating excellent amplification. In addition, to demonstrate microfluidic infrared PCR using clinical specimens, we successfully amplified and detected both influenza A and B from human nasopharyngeal swabs. Thermal multiplexing is scalable and applicable to challenges such as pathogen detection where patients presenting non-specific symptoms need to be efficiently screened across a viral or bacterial panel.  相似文献   
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Businesses have long relied on a variety of strategies to improve quality, efficiency, and service. Some ideas that have persisted over time are Six Sigma and Lean. While Six Sigma, originally intended for manufacturing, focuses on quality and Lean mainly addresses waste, many of the tools and principles involved can also apply to libraries. This article will review the literature on Lean and Six Sigma as they are used in business and then as they have been used in libraries. The resulting discussion will cover how the principles can be applied to better connect with stakeholders by mapping processes and discovering what is value added (VA) versus nonvalue added (NVA), anticipating failure modes using the failure mode and effects analysis (FMEA) framework, and implementing control plans to maintain quality processes and service.  相似文献   
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Fake news has become a prominent topic of public discussion, particularly among elites. Recent research has explored the prevalence of fake news during the 2016 election cycle and possible effects on electoral outcomes. This scholarship has not yet considered how elite discourse surrounding fake news may influence individual perceptions of real news. Through an experiment, this study explores the effects of elite discourse about fake news on the public’s evaluation of news media. Results show that exposure to elite discourse about fake news leads to lower levels of trust in media and less accurate identification of real news. Therefore, frequent discussion of fake news may affect whether individuals trust news media and the standards with which they evaluate it. This discourse may also prompt the dissemination of false information, particularly when fake news is discussed by elites without context and caution.  相似文献   
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Structuring job interviews is a method of decreasing bias and increasing the predictive validity of job performance, but research suggests that applicants can react negatively to structure (Chapman & Zweig, 2005) and that negative attitudes about selection tools can predict performance (Hausknecht, Day, & Thomas, 2004). The current exploratory study investigates how structuring the job interview in conjunction with priming the ethnicity and sex of the applicant, and in some conditions providing an explanation of the structure, affected post‐interview cognitive ability performance. Three levels of structure were randomly assigned. Those who experienced a structured interview without an explanation of its purpose scored lower than those who experienced an unstructured interview, but those who experienced a structured interview with an explanation of its purpose did not score lower than those who experienced an unstructured interview. Scores differed for females and Hispanics depending on the structure condition, but not in the same manner. Implications for recruitment, selection, and performance management are discussed.  相似文献   
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