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981.
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   
982.
ABSTRACT

Amid rising controversy around the alleged distinctions between merit and excellence lies a familiar refrain, scarcity. The narrative of academic scarcity, proclaiming the insufficient numbers of scholars and academics of color, permeates conversations in higher education. We suggest that the academic scarcity narrative, a remnant of stagnant logics of diversity, circulates as a contemporary mechanism of what we name disciplinary containment. Extending disciplinary conversations around rhetorical containment, we argue that disciplinary containment perpetuates whiteness.  相似文献   
983.
Current conceptions of accountability imply that, in order for teachers to be able to hold themselves to account, they need first to have cultivated certain ‘professional dispositions’. But these conceptions fail to acknowledge the extent to which teachers are first and foremost accountable ‘as such’. For the early existentialist thought of the philosopher Jean‐Paul Sartre, this relates to a kind of responsibility premised on the ways in which we are always and inevitably responding to the world in which we find ourselves (with others). In this paper, I offer a reconceptualisation of teacher accountability in light of this, one that recognises implicit responses in classroom situations as underpinned by the subjectivity of those who bring these situations to light—often in subtle and immeasurable ways.  相似文献   
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This article focuses on counseling research in the community college context. The article suggests the need for a robust community college knowledge base, describes some limitations of the current community college literature, and suggests a framework for more effective work in this area. The authors’ own experiences and selected examples of published studies are used as illustrations of the hurdles encountered and solutions available when examining counseling theories, practices, and outcomes in 2‐year settings.  相似文献   
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At the University of Maine, middle and high school teachers observed more than 250 university science, technology, engineering, and mathematics classes and collected information on the nature of instruction, including how clickers were being used. Comparisons of classes taught with (n = 80) and without (n = 184) clickers show that, while instructional behaviors differ, the use of clickers alone does not significantly impact the time instructors spend lecturing. One possible explanation stems from the observation of three distinct modes of clicker use: peer discussion, in which students had the opportunity to talk with one another during clicker questions; individual thinking, in which no peer discussion was observed; and alternative collaboration, in which students had time for discussion, but it was not paired with clicker questions. Investigation of these modes revealed differences in the range of behaviors, the amount of time instructors lecture, and how challenging the clicker questions were to answer. Because instructors can vary their instructional style from one clicker question to the next, we also explored differences in how individual instructors incorporated peer discussion during clicker questions. These findings provide new insights into the range of clicker implementation at a campus-wide level and how such findings can be used to inform targeted professional development for faculty.  相似文献   
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