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991.
992.
BackgroundIndividuals with diabetes have greater central arterial stiffness, wave reflections, and hemodynamics, all of which promote the accelerated cardiovascular pathology seen in this population. Acute aerobic exercise has been shown to be an effective strategy for reducing central arterial stiffness, wave reflections, and hemodynamics in healthy individuals; however, the effects of acute aerobic exercise in reducing these outcomes is not well established in people with diabetes. Recently, implementation of high-intensity interval exercise (HIIE) has shown superior improvements in cardiovascular health outcomes when compared to traditional aerobic exercise. Yet, the effect of HIIE on the aforementioned outcomes in people with diabetes is not known. The purpose of this study was to (i) describe the central arterial stiffness, wave reflections, and hemodynamic responses to a bout of HIIE and moderate-intensity continuous exercise (MICE) in adults with diabetes; and (ii) compare the effects of HIIE and MICE on the aforementioned outcomes.MethodsA total of 24 adult men and women (aged 29–59 years old) with type 1 (n = 12) and type 2 (n = 12) diabetes participated in a randomized cross-over study. All participants completed the following protocols: (i) HIIE: cycling for 4 × 4 min at 85%–95% of heart rate peak (HRpeak), interspersed with 3 min of active recovery at 60%–70%HRpeak; (ii) MICE: 33 min of continuous cycling at 60%–70%HRpeak; and (iii) control (CON): lying quietly in a supine position for 30 min.ResultsA significant group × time effect was found for changes in central systolic blood pressure (F = 3.20, p = 0.01) with a transient reduction for the HIIE group but not for the MICE or CON groups. There was a significant group × time effect for changes in augmentation index at a heart rate of 75 beats/min (F = 2.32, p = 0.04) with a decrease following for HIIE and MICE but not for CON. For all other measures of central arterial stiffness and hemodynamics, no significant changes were observed (p > 0.05).ConclusionA bout of HIIE appears to lead to a greater transient reduction in central systolic blood pressure than the reduction observed following MICE; however, both HIIE and MICE improved augmentation index at a heart rate of 75 beats/min in people with diabetes. There was no significant difference in response to HIIE and MICE in all outcomes. This provides preliminary evidence on the role of HIIE on such outcomes in people with diabetes. 相似文献
993.
Kerlinger's theory of social attitudes asserts that attitudes toward educational practices can be represented by the independent dimensions of progres-sivism and traditionalism. This study focused on the relationship between these attitudes and the philosophies of realism and pragmatism. A sample of 152 graduate students in education completed three instruments measuring educational attitudes and the basic and applied philosophies. Factor analytic results supported a dualistic theory rather than a bipolar theory for attitudes and philosophies. Pragmatists supported the progressive referents of children's interests and social development as educational goals, while realistsy supported traditional concepts emphasizing structure and the learning of content. The results are discussed in terms of the consistency between educational attitudes and a teacher's philosophy. 相似文献
994.
995.
996.
Keith?KoenigEmail author Nan?Davis?Mitchell Thomas?E.?Hannigan J.?Keith?Clutter 《Sports Engineering》2004,7(2):105-117
The speed at which a player can swing a bat is central to the games of baseball and softball, determining, to a large extent,
the hit speed of the ball. Experimental and analytical studies of bat swing speed were conducted with particular emphasis
on the influence of bat moment of inertia on swing speed. Two distinct sets of experiments measured the swing speed of colege
baseball and fast-pitch softball players using weighted rods and modified bats. The swing targets included flexible targets,
balls on a tee and machine pitched balls. Internal mass alterations provided a range of inertial properties. The average measured
speeds, from 22 to 31 m s−1, are consistent with previous studies. Bat speed approximately correlates with the moment of inertia of the bat about a vertical
axis of rotation through the batter's body, the speed generally decreasing as this moment of inertia increases. The analytical
model assumes pure rotation of the batter/bat system about a vertical axis through the batter's body. Aerodynamic drag of
the batter's arms and the bat is included in the model. The independent variable is bat moment of inertia about the rotation
axis. There is reasonable agreement between the model and the measured speeds. Detailed differences between the two suggest
the importance of additional degrees of freedom in determining swing speed. 相似文献
997.
Daena J. Goldsmith Jennifer J. Bute Kristin A. Lindholm 《Journal of Applied Communication Research》2013,41(1):65-86
Heart patients are frequently advised to make lifestyle changes and communication with a romantic partner can help or hinder adoption of heart healthy behaviors. However, talking about lifestyle change can have both positive and negative meanings and this can create dilemmas for couples. We engaged in an interpretive analysis of interviews with 25 patients and 16 partners to identify the ways they managed the meanings of lifestyle change talk. Their communicative strategies included rationing talk, saying it nicely and framing it cooperatively. Each strategy had advantages and disadvantages as well as optimal conditions. We also identified interpretive lenses that shaped the meaning of talk, including legitimacy, patience, emphasizing the positive, moderation, benefits for both people, and perceived compliance. Finally, environmental resources (such as household patterns and communication with the social network) contextualized the meaning of talk. We proposed a model of the interrelated influence of communication, interpretation, and environment on the meanings of talking about lifestyle change. 相似文献
998.
Faye A. Chadwell 《资料收集管理》2013,38(1):3-18
Numerous publications on patron-driven acquisition (PDA) for print books and similar materials have reported that patron-requested materials circulate more. Tying circulation to selector may be failing to address the complex of factors that contributes to items' circulation. In the present study, the authors revisit a PDA program's data and to determine whether PDA print books' circulation advantage persists when the potential interactions of several additional variables are taken into account. As with prior studies, library patrons were significantly better predictors of circulation than were librarians or approval plans. However, librarians proved to be significantly better predictors than were approval plans. 相似文献
999.
Trait argumentativeness and argumentativeness in the workplace, a particular situation, were examined with regard to gender of the respondent, rank/status of the respondent in the organization, and existence of a formal employee participation program. A main effect for gender showed men displayed the trait to a greater degree than women. There was a strong correlation between general trait argumentativeness and workplace argumentativeness, measured at a two‐week interval, which adds strength and validity to the trait measure of argumentativeness. The influence of the cross‐situaiional consistency nature of the trait was evidenced in this study. 相似文献
1000.
Erica Weintraub Austin Christopher Knaus Ana Meneguelli 《Communication Research Reports》2013,30(4):418-430
A random telephone survey (N = 255) of Washington state parents of children between the ages of 2 and 17 assesses parents’ reported patterns of interaction with their children regarding television, along with parental viewing habits and perceptions of television content. Demographic differences in mediation and coviewing patterns, as well as parental attitudes toward television, are explored, and explanations for these differences are considered. It is concluded that education is a weak predictor of mediation levels, single parents do not differ from dual parents in attitudes about television, and that the negative relationship of income to positive mediation and use of television as a babysitter is related more to overall viewing patterns and environmental constraints, rather than to attitudinal differences. It is suggested that demographics hold little value jar explaining why and how parents hold particular attitudes or engage in particular behaviors relevant to television and parenting. 相似文献