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591.
    
Abstract

Objectives: To examine within-person and between-person sources of variation in the relationship between physical activity and cognition in older adults participating in a walking program. To explore whether demographic, health and fitness variables, and their interactions with activity, are significant predictors of cognition.

Design: Brief longitudinal burst design.

Participants: 118 participants (91 females, mean age?=?72.81?+ 5.24 years).

Main Outcome Measures: Cognition, self-reported moderate-to-vigorous walking and self-reported moderate-to-vigorous physical activity were assessed at baseline and 6, 9, 12 and 16 weeks follow-up. Attendance at weekly walks was also recorded.

Results: Within-persons, changes in physical activity were related to select measures of executive functioning, with increased activity predictive of better cognition (three of four cognitive functions, p<.05). Between-persons, activity was also associated with cognition (two of four cognitive functions, p<.05). Younger age and higher education were related to better cognition. Interactions of demographic, health, and fitness variables with changes in within-person activity were generally non-significant.

Conclusion: The results highlight the importance of distinguishing within- from between-person effects in longitudinal analyses of the association between physical activity and cognition. This stringent within-person test of association underscores the potential value of simple physical activity interventions for improving cognitive function.  相似文献   
592.
    
A growing body of research is examining the strengths and weaknesses of specific after school programs and their effect on youth outcomes. Few reviews, however, have sought to examine the components of citywide system-building—to understand intentional efforts to develop, support and sustain high quality after school programming across a community. Beginning in the mid-1990s and continuing through the present, private funders, public officials and program practitioners in cities across America have joined together to build systems to support the expansion and improvement of after school programs at the city-level. This paper presents the community context and underlying principles that drove the development of Baltimore’s After-School Strategy; articulates a set of system components derived from this experience and the available literature; and lays out future work to expand high quality after-school opportunities for youth in Baltimore and in other distressed urban environments.  相似文献   
593.
    
ABSTRACT

Human microbial communities are bodies of microorganisms that reside in or on different body parts. Importantly, they have been found to affect human health. However, scientific research on human microbial communities has created new challenges for human subject recruitment. First, individuals are asked to collect samples of bodily substances that can be seen as repulsive (e.g. feces and urine). Second, because scientists want to understand how human microbial communities evolve over time, individuals are asked to commit to a regular sample collection for extended periods of time. A longitudinal qualitative study of the work of scientists, physicians, research staff, and study coordinators involved in a human microbiome research project has found that these actors can bypass some aspects of these recruitment and retention challenges through ‘tuning work’. Tuning work is a collaborative process where professionals agree to adjust their practices towards shared goals. Such professionals reconfigure their work practices, personal routines, and the study protocol in an effort to obviate cultural taboos against handling bodily substances. The burden of long-term participation provides fewer opportunities for tuning work for these professionals, however. As such, long-term commitment by human subjects remains a recruitment and retention obstacle.  相似文献   
594.
Conflict of interest is an issue that has been put in the spotlight by the commercial application of the new biomedical technologies. This paper presents the approach of the Council of Europe and the binding legal instruments to deal with this problem. The main focus is on the Convention on Human Rights and Biomedicine, and its draft additional Protocol on Biomedical Research. An earlier version of this paper was presented at an International Conference on “Conflict of Interest and its Significance in Science and Medicine” held in Warsaw, Poland on 5–6 April, 2002. The views expressed are personal and do not necessarily reflect any official position of the Council of Europe.  相似文献   
595.
    
This study examines the motivations for and the outcomes of mid-life career change among a sample of 73 men who had left professional and managerial careers between the ages of 34 and 54. Measures of personal desire for change and external pressure to leave were dichotomized to produce a typology of career changers: Drift-outs, Opt-outs, Force-outs, and Bow-outs. The four types of changers were found to differ on a number of variables, including: amount of education completed, additional schooling undertaken to change careers, time taken to make the change, radicalness of change, and the importance of personal values in deciding to leave their former careers. Overall, respondents were found to be highly satisfied with their career redirection.  相似文献   
596.
面对21世纪的人类“圣餐” 中国该怎样分享   总被引:2,自引:1,他引:1  
人类基因组计划(HumanGenomeProject,HGP)实施7年来已取得巨大进展,不断涌现的新技术、新策略使人基因组全长测序有望在今后几年内提前完成,结构基因组学时代正向功能基因组学时代过渡。然而,发达国家之间的基因争夺战亦愈演愈烈,中国现正面临着严峻挑战。本文简要介绍了HGP研究的国际背景、最新进展及发展趋势,目的在于分析目前我国HGP研究所存在的问题和探讨其发展对策  相似文献   
597.
    
It is well known that we utilize internalized representations (or schemas) to direct our eyes when exploring visual stimuli. Interestingly, our schemas for human faces are known to reflect systematic differences that are consistent with one's level of racial prejudice. However, whether one's level or type of racial prejudice can differentially regulate how we visually explore faces that are the target of prejudice is currently unknown. Here, White participants varying in their level of implicit or explicit prejudice viewed Black faces and White faces (with the latter serving as a control) while having their gaze behaviour recorded with an eye-tracker. The results show that, regardless of prejudice type (i.e., implicit or explicit), participants high in racial prejudice examine faces differently than those low in racial prejudice. Specifically, individuals high in explicit racial prejudice were more likely to fixate on the mouth region of Black faces when compared to individuals low in explicit prejudice, and exhibited less consistency in their scanning of faces irrespective of race. On the other hand, individuals high in implicit racial prejudice tended to focus on the region between the eyes, regardless of face race. It therefore seems that racial prejudice guides target-race specific patterns of looking behaviour, and may also contribute to general patterns of looking behaviour when visually exploring human faces.  相似文献   
598.
    
Kako E 《Cognitive Science》2005,29(2):223-260
Why are some words easier to learn than others? And what enables the eventual learning of the more difficult words? These questions were addressed for nouns using a paradigm in which adults were exposed to naturalistic maternal input that was manipulated to simulate access to several different information sources, both alone and in combination: observation of the extralinguistic contexts in which the target word was used, the words that co‐occurred with the target word, and the target word's syntactic context. Words that were not accurately identified from observation alone were both abstract (e.g., music) and concrete (e.g., tail). Whether a noun could be learned from observation depended on whether it labeled a basic‐level object category (BLOC). However, the difference between BLOC labels and non‐BLOC labels was eliminated when observation was supplemented with linguistic context. Thus, although BLOC labels can be learned from observation alone, non‐BLOC labels require richer linguistic context. These findings support a model of vocabulary growth in which an important role is played by changes in the information to which learners have access.  相似文献   
599.
This research explores the hypothesis that major personality traits are systematically associated with social regulation response tendencies. Specifically, the adaptive function of specific traits from ‘Big-Five’ and HEXACO models were evaluated in terms of how they are understood and utilized in predicting the behaviors of others. Big-Five factors of agreeableness and conscientiousness track tendencies to obey or break social contract and precautionary rules, but not discriminatively nor as predicted. HEXACO traits, however, provided discriminative patterns of associations between personality and response tendencies (within individuals and for third-person associations, cross-culturally) in greater accord with previous work. Honesty–humility is associated with social contract behaviors and conscientiousness is associated with precaution behaviors, consistent with conceptualizations as psychological adaptations for tracking fitness-relevant individual differences.  相似文献   
600.
This article focuses on political human rights and on the empirically assessed legitimation of these rights. This research considers the rights of refugees, the active and passive right to vote, and the right of protest. Given that the research is empirical research, respondents are requested to express agreement, disagreement or neutrality. The assumption is that contextual factors influence people’s assessment of rights. One contextual factor is, firstly, the concept of human dignity. International human rights covenants regard human dignity as the very foundation of all rights. That said, the concept of human dignity is subject to different understandings and – certainly in the past – the understanding of what constitutes human dignity has varied. Dignity can be related to the appreciation of the person given by others, to the moral behaviour of a person, and it can be understood as inherently related to the individual as a human being. It is this last understanding that forms the basis of modern declarations of human rights. Furthermore, the respondents’ value orientations and religious beliefs, along with society’s socio-political perception, will be examined to ascertain whether these factors have any influence on respondents’ attitudes towards political rights. The key question is: does human dignity influence people’s view of the legitimacy of political rights and do other factors also count? The empirical analysis was undertaken done with German youth (N=2244). Findings show that the concept of inherent human dignity is a strong predictor for respondents’ attitudes towards political rights, but that it is not the unique predictor; relevant concepts are the value orientation of youth and their socio-political orientation. The significance of religious beliefs as a predictor is low.  相似文献   
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