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881.
Frequent changes are potentially damaging to companies in sectors where there are long investment lead times and which are unable to respond quickly to changes in government policy. This paper demonstrates the risks which governments run by not providing a consistent, considered policy framework which would allow companies to plan their strategies with a reasonable degree of certainty.  相似文献   
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Volunteers fill sandbags while storm clouds are brewing so the sacks will be ready when floodwaters rush in. Similarly, skin cells prepare for a flood of molten proteins by reinforcing a protein-chopping system, according to new research. This boost might explain how cells and organisms protect themselves from severe stress.  相似文献   
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Length of stay in hospital (LOS) is a widely used outcome measure in Health Services research, often acting as a surrogate for resource consumption or as a measure of efficiency. The distribution of LOS is typically highly skewed, with a few large observations. An interesting feature is the presence of multiple outcomes (e.g. healthy discharge, death in hospital, transfer to another institution). Health Services researchers are interested in modeling the dependence of LOS on covariates, often using administrative data collected for other purposes, such as calculating fees for doctors. Even after all available covariates have been included in the model, unexplained heterogeneity usually remains. In this article, we develop a parametric regression model for LOS that addresses these features. The model is based on the time, T, that a Wiener process with drift (representing an unobserved health level process) hits one of two barriers, one representing healthy discharge and the other death in hospital. Our approach to analyzing event times has many parallels with competing risks analysis (Kalbfleisch and Prentice, The Statistical Analysis of Failure Time Data, New York: John Wiley and Sons, 1980)), and can be seen as a way of formalizing a competing risks situation. The density of T is an infinite series, and we outline a proof that the density and its derivatives are absolutely and uniformly convergent, and regularity conditions are satisfied. Expressions for the expected value of T, the conditional expectation of T given outcome, and the probability of each outcome are available in terms of model parameters. The proposed regression model uses an approximation to the density formed by truncating the series, and its parameters are estimated by maximum likelihood. An extension to allow a third outcome (e.g. transfers out of hospital) is discussed, as well as a mixture model that addresses the issue of unexplained heterogeneity. The model is illustrated using administrative data.  相似文献   
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Many adults with multiple chemical sensitivity (MCS) must prematurely exit the workforce because of the severity of their MCS symptoms, the resulting disability stigma, and their unmet needs for on-the-job accommodations. To help individuals with MCS continue working or re-enter employment, rehabilitation professionals must understand the barriers resulting in unemployment and implement interventions to reduce or remove those barriers. In this article, the Ecological Model of Career Development is presented as a scheme for identifying barriers and implementing rehabilitation interventions to improve the employment outcomes among people with MCS.  相似文献   
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The purpose of this study was to use the constructs of the theory of planned behavior (TPB) to gain a better understanding of the factors influencing older adults' participation in strength training. Two hundred men and women age 55 years and older were purposely sampled from seniors' centers in Ontario Canada. Participants completed a TPB questionnaire and reported their current physical activity participation. It was hypothesized that perceived behavioral control followed by attitude would be the strongest determinants of strength-training intentions and that intention would be the strongest determinant of strength-training behavior. Regression analyses revealed that subjective norm and perceived behavioral control explained 42% of the variance in intention and intention explained 40% of the variance in behavior. Gender and current strength-training participation did not significantly moderate the relationship between the TPB variables. The results suggest that interventions targeting subjective norm and perceived control might be helpful in promoting strength-training behavior among older adults.  相似文献   
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The purpose of this project was to evaluate the effectiveness of an initial screening and referral process in reducing the impact of musculosketetal injuries among soldiers attending Health Care Specialist training. Musculoskeletal injury among Army Health Care Specialist students have been reported to be approximately 24% for men and 24-30% for women. The highest student visit rate to the troop medical clinic for musculoskeletal injuries, for men and women, occurs during the first week of training. Anecdotal reports indicate that many students arrive for training with existing injuries or symptoms. This project was designed to assess whether formalized early screening, referral, and intervention could 1) identify arriving students who need musculoskeletal injury-related medical attention, 2) reduce the number of students receiving limited duty status during their 10-week training, 3) decrease the total number of limited duty days for students, and 4) decrease the number of students who cannot graduate due to musculoskeletal injury. Students (N=291) from one company were divided into three groups of 97 students. Three methods were used to screen and refer students for medical intervention: 1) traditional (T), 2) by health care providers (HCP), or 3) by Drill Sergeants (DS). Screening by HCP and DSs involved using a new screening tool to identify and consequently refer students with symptoms to a troop medical clinic (TMC) for early evaluation and intervention. Using the screening tool, HCPs identified 92% of students with injuries, while DSs accurately identified 80%. The screening did not reduce the number of students receiving limited duty status, total limited duty days, or the number of students that could not graduate due to musculoskeletal injury ("holdovers") (p>0.05). The screening tool demonstrated good sensitivity and specificity whether conducted by HCPs or DSs. It failed to demonstrate efficacy in reducing the impact of musculoskeletal injuries among Combat Medic soldiers, as measured by limited duty days and holdovers.  相似文献   
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