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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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Children's ability to discriminate reflections and rotations of visual stimuli was examined within the confines of a mental rotation task. It was hypothesized that success would be affected by both characteristics of the stimulus and by the subtlety of the discrimination required. Forty 3- to 4-year-old children were directed to mentally rotate a stimulus a given number of degrees and to discriminate the appearance of the rotated stimulus from among a set of alternatives. Four stimuli differing in the number of visual orientation cues were utilized across 24 trials. A significant effect was found for number of orientation cues, and data indicated the difficulty children experienced detecting reflections, a task which bears close resemblance to the yes/no option in prototypic rotation studies. Children were only successful with a limited range of stimuli when discrimination of a reflected foil was not required. Results are discussed in light of discrepant findings about children's kinetic imagery ability and the advisability of using this particular paradigm with young Children.  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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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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