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71.
Forty-nine previously sedentary or low active individuals aged 40-71 years were allocated to three groups. The long walking group participated in an 18-week walking programme which consisted of walks lasting 20-40 min; the repetitive short walking group completed walks of between 10 and 15 min, up to three times a day, with no less than 120 min between each walk; and the control group maintained their low level of activity. Both walking programmes began at a prescribed 60 min x week(-1), which increased steadily up to 200 min x week(-1) by week 12. During the study, the long walking group walked for an estimated 2514 min (139 min x week(-1)), expending an estimated 67.5 MJ (3.72 MJ x week(-1)) at an estimated 73% of their age-predicted maximum heart rate and 68% of their estimated VO2max. The repetitive short walking group walked for an estimated 2476 min (135 min x week(-1)), expending an estimated 58.5 MJ (3.17 MJ x week(-1)) at an estimated 71% of their age-predicted maximum heart rate and 65% of their estimated VO2max. The results showed a statistically significant reduction in heart rate during a standardized step test (pre- vs post-intervention) in both walking groups, indicating an improvement in aerobic fitness, although the control group showed a higher average heart rate during the post-intervention test, indicating reduced fitness. When compared with the male subjects pre-intervention, the females possessed more favourable levels of high-density lipoprotein (HDL) cholesterol (P< 0.001), apolipoprotein (apo) AI (P < 0.001) and ratios of total cholesterol:HDL cholesterol (P< 0.02) and low-density lipoprotein (LDL) cholesterol: HDL cholesterol (P< 0.02). Compared with the controls post-intervention, the walking groups showed no statistically significant changes in total cholesterol, LDL cholesterol, HDL cholesterol, apo AI, apo AII, apo B, or the ratios of total cholesterol: HDL cholesterol, LDL cholesterol: HDL cholesterol, apo AI: apo B or apo AI: apo AII (P > 0.05). Relative to the walking groups, factor XIIa increased in the control group (P < 0.05). We conclude that, although both walking programmes appeared to improve aerobic fitness, there was no evidence of improvements in the blood lipids or associated apolipoproteins of the walking groups. Further analysis indicated that this apparent lack of change may have been related to the subjects' relatively good pre-intervention blood lipid profiles, which restricted the potential for change. The implications of the observed changes in the coagulation/fibrinolytic factors remain unclear.  相似文献   
72.
Transitions from education into work, or as part of career change and development, are increasingly central to policy debate and academic inquiry. However, the role that employers play in shaping transition is often overlooked. In this paper, we examine this issue through the experiences of a graduating cohort of ‘degree apprentices’. We present original analysis of new empirical data from what we believe to be the first substantive qualitative longitudinal research conducted with those experiencing this new vocational pathway in the English Apprenticeships system. Through analysis of repeat semi-structured interviews with 22 degree apprenticeship graduates (44 interviews in total), we provide early empirical insights into experiences of this new pathway and add to existing theoretical conceptualisations of transition within the educational literature and the employer's role within it. We show that the degree apprentice to graduate transition can be broken down into three key stages: ‘getting in’, ‘getting on’ and ‘going further’, and that employers—at both strategic and relational levels—shape experiences at each stage.  相似文献   
73.
Abstract

Carnosine was originally discovered in skeletal muscle, where it exists in larger amounts than in other tissues. The majority of research into the physiological roles of carnosine have been conducted on skeletal muscle. Given this and the potential for muscle carnosine content to be increased with supplementation, there is now a large body of research examining the ergogenic effects (or otherwise) of carnosine. More recent research, however, points towards a potential for carnosine to exert a wider range of physiological effects in other tissues, including the brain, heart, pancreas, kidney and cancer cells. Taken together, this is suggestive of a potential for carnosine to have therapeutic benefits in health and disease, although this is by no means without complication. Herein, we will provide a review of the current literature relating to the potential therapeutic effects of carnosine in health and disease.  相似文献   
74.
The authors examine the problems of ex-post evaluation of the benefits deriving from services provided by Government Laboratories. They concentrate on the difficulties of conducting meaningful ex-post studies since they feel that too many claims are made on the basis of inadequate, incomplete economic assessments using data that would not be substantiated if probed deeply. Their views are based on a review of nine years' practical evaluation experience.The paper defines three ways in which services/information sources can link up with intended recipients, and discusses the practical problems associated with assessing the impact of services in each case. These problems range from sampling errors and sample bias in questionnaire approaches, to limited respondent knowledge and perspective. Critical probing can overcome these difficulties in some, though not all, instances, since there are issues of principle that prohibit unique attribution of benefits to specific initiatives in many ex-post analyses. The use of cost recovery as a proxy measure of worth is reviewed.The authors point out that ex-ante appraisal of profits is not subject to the same constraints and avoids many of the pitfalls of ex-post evaluation.  相似文献   
75.
Two experiments were performed to determine the effect of sample duration (0.1, 2, and 4 sec), delay interval (.03, 4, 8, 16, and 32 sec), and type of stimulus (color and shape) on the matching performance of rhesus monkeys. In Experiment 1, the 15 possible delay-duration combinations were randomly presented in blocks of 15 trials. In Experiment 2, each duration was held constant and the five delays randomly presented. Then each delay interval was held constant with the three durations randomly varied. Matching performance increased as sample duration increased (ps < .01 and .005), while length of delay did not significantly affect performance. The type of stimuli paired in the matching test significantly affected performance (ps < .05 and .10) with the shape/shape choices leading to the poorest performance. Stimulus discriminability and amount of training with brief sample durations were implicated as significant determinants of matching performance.  相似文献   
76.
The present study adopted an intergroup approach to information sharing and ratings of work team communication in a public hospital (N?=?142) undergoing large-scale restructuring. Consistent with predictions, ratings of communication followed a double ingroup serving bias: while team members reported sending about the same levels of information to double ingroup members (same work team/same occupational group) as they did to partial ingroup members (same work team/different occupational group), they reported receiving less information from partial ingroup members than from double ingroup members and rated the communication that they received from partial ingroup members as less effective. We discuss the implication of these results for the management of information sharing and organizational communication.  相似文献   
77.
The Writer in Education   总被引:1,自引:0,他引:1  
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78.
79.
Persistent disparities exist between African American children and their European American counterparts across developmental domains. Early childhood intervention may serve to promote more positive outcomes among African American children. The current study examined whether and how the Early Head Start (EHS) program benefited African American children at the end of the program, when they were 36 months of age, as well as the parenting these children experienced and how this affected their developmental outcomes. The data show a wide and strong pattern of impacts of EHS for African American children and families. Path analysis yielded findings that suggested a direct effect of EHS on specific child outcomes and parenting processes within this group of African American families. Parental supportiveness and cognitive stimulation emerged as important direct influences on African American children's outcomes and as pathways through which Early Head Start benefits these children. These findings are discussed in the context of early childhood intervention practice.  相似文献   
80.
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