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ABSTRACT

The length of telomeres is an objective measure of biologic ageing. This study evaluated the extent minutes of walking per week are associated with leukocyte telomere length (LTL) in a random sample of 5,823 U.S. adults. The investigation was cross-sectional and data were obtained from the National Health and Nutrition Examination Survey (NHANES). LTL was measured by the quantitative polymerase chain reaction method. Walking minutes was calculated from walking frequency and duration measures. Results showed that for each year of chronological age, telomeres were 15.6 base pairs shorter (P < 0.0001). With walking minutes and LTL treated as continuous variables, the relationship was quadratic, not linear (F = 11.2, P = 0.0023). With walking time divided into three categories, adults who performed ≥ 150 minutes of walking per week had longer telomeres than those who did no regular walking, and those who did some, but less than the recommendation (F = 5.0, P = 0.0137). Regular walkers were estimated to have a biologic ageing advantage associated with 6.5–7.6 years less biologic ageing compared to non-walkers, after adjusting for covariates. Additional investigations designed to study causality and the mechanisms associated with the walking and LTL relationship are needed.  相似文献   
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Software engineering education can be viewed as a challenging task. Computer science students tend to focus on the programming aspects of a project, and take a “hacking approach” to completing a project, rather than viewing the process. Our course material includes teaching the Personal Software Process (PSP). Students are required to produce defect and effort metrics, as well as project summary reports. Tools to assist information recording and production of reports are difficult for students to access. The cost in terms of financial and learning time is usually too high at the educational level to justify using commercial tools that are available for the professional software engineer. We have developed a tool—Personal Assistant for Software Engineers—to aid students in the learning of the PSP. The tool has been successfully used in four subjects for a semester. Following feedback and evaluation, it has been redesigned, and is currently in stage two. The tool has been useful for students, and has automated the previous manual process of producing time and defect reports, along with project summaries, thus allowing them to focus on the meaning of the information.  相似文献   
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Mooses and colleagues suggest that running economy alone does not explain superior distance running performance in elite Kenyan runners. Whilst we agree with the multi-factorial hypothesis for Kenyan running success, we do not believe that running economy can be overlooked to the extent that it was based on this particular study. Based on the methods used and the range of athletes tested, in this response letter we question whether this study provides any basis for downplaying the influence of running economy or suggesting that other factors compensate for it to enable superior performance.  相似文献   
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