Metabolic cost of running is greater on a treadmill with a stiffer running platform

Exercise testing on motorised treadmills provides valuable information about running performance and metabolism; however, the impact of treadmill type on these tests has not been investigated. This study compared the energy demand of running on two laboratory treadmills: an HP Cosmos (C) and a Quinton (Q) model, with the latter having a 4.5 times stiffer running platform. Twelve experienced runners ran identical bouts on these treadmills at a range of four submaximal velocities (reported data is for the velocity that approximated 75–81% VO_2max). The stiffer treadmill elicited higher oxygen consumption (C: 46.7 ± 3.8; Q: 50.1 ± 4.3 ml·kg^?1 · min^?1), energy expenditure (C: 16.0 ± 2.5; Q: 17.7 ± 2.9 kcal · min^?1), carbohydrate oxidation (C: 9.6 ± 3.1; Q: 13.0 ± 3.9 kcal · min^?1), heart rate (C: 155 ± 16; Q: 163 ± 16 beats · min^?1) and rating of perceived exertion (C: 13.8 ± 1.2; Q: 14.7 ± 1.2), but lower fat oxidation (C: 6.4 ± 2.3; Q: 4.6 ± 2.5 kcal · min^?1) (all analysis of variance treadmill comparisons P < 0.01). This study confirms that caution is required when comparing performance and metabolic results between different treadmills and suggests that treadmills will vary in their comparability to over-ground running depending on the running platform stiffness.     

Curriculum Development for Business and Industry

Curriculum development is usually associated with educational institutions. As a result, there are few curriculum development models that have been specifically created for the business and industrial setting. Those that have been published tend to adopt a “let's begin at the beginning” approach. They prescribe starting as though nothing previously existed within the organization to provide personnel training and development. The Professional Development Curriculum (PDC) model presented in this article starts with what already exists organizationally. It adopts a convergence strategy. It begins by systematically matching known needs with known resources and then, over a series of generations, creates closer fits between needs and resources. The model has been applied to two very different settings in General Motors: all GM wholesale divisions and GM's Latin American retail and wholesale operations. The results have been positive in creating coherent curricula tied to career path progressions for all employees in these organizations. Evolutionary and practical, this PDC model can be applied to any business or industry to build competency-based curricula that not only provide personnel development support systems for today's needs, but for tomorrow's as well.     

Comparison of Recovery Procedures for the Reduction of Exercise Stress

Abstract

This study investigated the effects of three types of recovery procedure on (a) circulatory recovery from a standardized bicycle ergometer exercise, (b) performance in a second standardized bicycle ergometer exercise, and (c) circulatory recovery from the second exercise. The recovery procedures were complete rest, light activity, and cold showers. Each of 10 male subjects underwent each recovery procedure on separate days. Analysis of variance for a randomized complete blocks design was used in the analysis of the data. Results indicated that cold showers decreased recovery heart rate after the first standardized exercise from 115 to 96 beats/minute and after the second exercise from 164 to 152 beats/ minute when compared with the other two conditions. Speed of performance in the second exercise was improved from 40.4 and 40.3 sec. in the case of rest and light activity to 38.9 sec. for cold showers. These improvements were all statistically significant at the .05 level. Three physiological explanations, not necessarily independent, are advanced: (a) local vasoconstriction of the skin vessels and vasodilatation of the muscle vessels causing a greater proportion of total blood flow to the working muscles, (b) establishment of a greater thermal gradient between the core and shell of the body allowing heat movement to the surface of the body by conduction between tissues rather than by skin blood flow, and (c) a decrease in sweat rate, thereby suppressing release of bradykinin, a vasodilator substance.     

退耕还林 40年来森林土壤氮库营养的动态变化研究(英文)

对 1962年以来采集的表层土壤和深层土壤样品进行培养实验,以研究退耕还林 40年来土壤氮的动态变化以及植被恢复对土壤氮库矿质化的影响.供试土样在专门设计的矿质化培养系统中,以温度 30℃、通气并保持土壤湿度的条件下培养 30d,以 2mol LKCl溶液浸提培养土并测定其氮含量.结果表明,土壤矿质氮及全氮含量均在造林的头 2 0年迅速下降,在 2 0年的林木生长过程中,生物吸收积累了土壤中约 80 %-90 %的有效氮,表明耕地中施入的氮对树木早期生长有着重要作用;树龄达 40年时,土壤原有矿质氮的 5 0 %-80 %已返还土壤.这一结果表明,森林地被已成为土壤营养的重要来源,并且森林生态系统提供的这种有机质可成为可持续利用的土壤氮资源.     

Using a Critical Service-Learning Approach to Facilitate Civic Identity Development

This article highlights elements of civic engagement programs that have the rich potential to facilitate civic identity development. Focusing on research with alumni, the study examines 3 civic engagement programs, the approaches of which are guided by critical service-learning. It explores elements of the experiences that alumni name as influential to their learning, development, and present commitments to understand the ways that civic engagement programs based in a critical service-learning approach can encourage them to develop commitments to active citizenship as exemplified by Knefelkamp's (2008) vision of a mature sense of civic identity.     

An introduction to independent learning skills for incoming medical students

A partnership was initiated between educators of the College of Medicine and the McGoogan Library at the University of Nebraska Medical Center to establish a new educational component for incoming medical students. The objective was to encourage the development of the students' independent information seeking skills. A three-day seminar was introduced in which the process of seeking information was emphasized rather than the final product. Cooperative development of the seminar resulted in a fresh approach to educating medical students at the College of Medicine and the emergence of an ongoing instructional link between the library faculty and educators in the College of Medicine.     

Fathers and mothers at play with their 2- and 3-year-olds: contributions to language and cognitive development

Father-child and mother-child engagements were examined longitudinally in relation to children's language and cognitive development at 24 and 36 months. The study involved a racially/ethnically diverse sample of low-income, resident fathers (and their partners) from the National Early Head Start evaluation study (n=290). Father-child and mother-child engagements were videotaped for 10 min at home during semistructured free play, and children's language and cognitive status were assessed at both ages. Fathers' and mothers' supportive parenting independently predicted children's outcomes after covarying significant demographic factors. Moreover, fathers' education and income were uniquely associated with child measures, and fathers' education consistently predicted the quality of mother-child engagements. Findings suggest direct and indirect effects of fathering on child development.