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Falls represent a major public health problem for older adults, and loss of balance (LOS) abilities is one of the primary causes of falls. Previous studies have shown that balance training is effective in improving physical function and decreasing risk of falls. However, little attention has been given specifically to balance training in older adults with very poor balance. The purpose of this study was to determine the effect of a 12-week customized balance exercise program on LOS for community-dwelling older women with poor balance ability. Twenty-four older women with poor balance (composite maximum excursion [MXEcomp] score of less than 70% based on Limits of Stability) were divided into an exercise group and control group. After 12 weeks of balance exercises, mean MXEcomp improved (p < .05) from 58.6% to 79.0% in the exercise group. EPEcomp (composite endpoint excursion), RTcomp (composite reaction time), SVcomp3 (composite sway velocity on thick foam with the eyes open), UG (up and go) also improved, but the functional reach and other static balance indexes did not change. These results indicated that balance training allows older adults with poor balance to improve dynamic balance ability and potentially reduce risk for falls.  相似文献   
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The qualitative study presented in this paper explored the perspectives of service-users, family members and staff about the impact of travel issues on the lives of mental health in-patients and carers. This topic was chosen because it was prioritised by members of Xplore, a service-user and carer research group, and has received little research attention. Travel problems were a significant issue for many service-users and carers, bound-up with mental health issues and the recovery experience. Travel facilitation through the funding of taxis and the provision of guides was appreciated. A few service-users and carers positively valued distancing from their previous home environment. The meaning of travel issues could only be understood in the context of individuals’ wider lives and relationships. The significance of the findings is discussed in relation to the social model of disability.  相似文献   
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This paper analyzes four animated films in order to explore themes of leadership crises and leadership emergence. Drawing on psychoanalysis and structuralist film studies, this paper explores leadership emergence as a mythic structure within the four films, arguing that these myths are structured around a struggle of a young novice against an evil power figure, and the overcoming of this figure through a process of self-discovery and maturation. Central themes include the relations between self-realization of leaders and the social harmony, the battle with evil leaders as an ego-struggle, and exile and journey as a precursor to mature leadership competence. The paper attempts to show how, following Miendl et al. [Meindl, J. R., Erlich, S. B. & Dukerich, J. M. (1985). The romance of leadership. Administrative Science Quarterly, 30, 78–102] leadership myths often conflate individual psychological well-being with social well-being, and add to this perspective that such a conflation may be key to understanding leadership myths as projections of internal psychological dynamics. More generally, it is argued that treating popular culture such as animated allegories as contemporary myth offers scholars a view into popular conceptions of leadership, possible illuminating the relationships between leadership and social organization.  相似文献   
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Asymptotic variance plays an important role in the inference using interval estimate of attributable risk. This paper compares asymptotic variances of attributable risk estimate using the delta method and the Fisher information matrix for a 2×2 case–control study due to the practicality of applications. The expressions of these two asymptotic variance estimates are shown to be equivalent. Because asymptotic variance usually underestimates the standard error, the bootstrap standard error has also been utilized in constructing the interval estimates of attributable risk and compared with those using asymptotic estimates. A simulation study shows that the bootstrap interval estimate performs well in terms of coverage probability and confidence length. An exact test procedure for testing independence between the risk factor and the disease outcome using attributable risk is proposed and is justified for the use with real-life examples for a small-sample situation where inference using asymptotic variance may not be valid.  相似文献   
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Dependence in outcome variables may pose formidable difficulty in analyzing data in longitudinal studies. In the past, most of the studies made attempts to address this problem using the marginal models. However, using the marginal models alone, it is difficult to specify the measures of dependence in outcomes due to association between outcomes as well as between outcomes and explanatory variables. In this paper, a generalized approach is demonstrated using both the conditional and marginal models. This model uses link functions to test for dependence in outcome variables. The estimation and test procedures are illustrated with an application to the mobility index data from the Health and Retirement Survey and also simulations are performed for correlated binary data generated from the bivariate Bernoulli distributions. The results indicate the usefulness of the proposed method.  相似文献   
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The systemic uptake of chloroform from dilute aqueous solutions into live hairless rats under conditions simulating dermal environmental exposure was studied. Whole blood was sampled during a 30-min immersion of an animal within water containing a known concentration of chloroform and then for 5.5 h following its removal from the bath. The amount of chloroform systemically absorbed was determined by comparing the AUCs of the blood concentration vs. time plots from dermal exposure to that obtained after IV infusion (for a period of 30 min) of an aqueous solution containing a known amount of chloroform (positive control). Although dermal data implied two-compartment disposition characteristics, IV infusion data fit best to a three-compartment disposition. Linear pharmacokinetics was observed both by IV administration and percutaneous absorption at the dose levels studied. Chloroform was detected in the rat blood as early as 4 min following exposure. Our findings suggest that about 10.2 mg of chloroform was systemically absorbed after dermal exposure of a rat to an aqueous solution of 0.44 mg/ml. This amount is substantially higher than the predictions of mathematical risk-models put forth by some investigators. However, when expressed as the "effective" permeability coefficient ( K peff), close agreement was noticed between our value and those estimated by others using physiologically based pharmacokinetic (PBPK) models. Also, in terms of K peff, reasonable agreement existed between our and another investigator's past estimates of uptake based on depletion of bath level of chloroform and the actual uptake measured in our current experiments. The estimated onset of systemic entry seen here is entirely consistent with our estimate of how long it takes to establish the diffusion gradient across the stratum comeum based on tape stripping.  相似文献   
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For analyzing incidence data on diabetes and health problems, the bivariate geometric probability distribution is a natural choice but remained unexplored largely due to lack of models linking covariates with the probabilities of bivariate incidence of correlated outcomes. In this paper, bivariate geometric models are proposed for two correlated incidence outcomes. The extended generalized linear models are developed to take into account covariate dependence of the bivariate probabilities of correlated incidence outcomes for diabetes and heart diseases for the elderly population. The estimation and test procedures are illustrated using the Health and Retirement Study data. Two models are shown in this paper, one based on conditional-marginal approach and the other one based on the joint probability distribution with an association parameter. The joint model with association parameter appears to be a very good choice for analyzing the covariate dependence of the joint incidence of diabetes and heart diseases. Bootstrapping is performed to measure the accuracy of estimates and the results indicate very small bias.  相似文献   
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