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91.
Cho YJ  Kim JY 《Work (Reading, Mass.)》2012,41(Z1):2545-2548
The aim of this study is to investigate the stationarity of the electromyographic (EMG) signals during isokinetic exertions of the trunk muscle. Six healthy subjects participated in this study. The erector spinae muscles were used to collect the signals. In order to simulate the isokinetic exercises of the trunk, a Cybex system with a trunk modular component was used. All subjects performed sustained exertions with a combination of load (25%, 50% MVC) and angular velocity (0, 15, 30 degree/s). The stationarity of the signals was tested by the reverse arrangements test and modified reverse arrangements test. In the results, the signal stationarity was high in all conditions in the reverse arrangements test. However, in the modified reverse arrangements test it was relatively low at about the 30 degree/s angular velocity. In the analysis of variance, the effect of angular velocity was statistically significant at the 0.05 significance level in the modified reverse arrangements test and Tukey's HSD grouping showed that the stationarity of 30 degree/s angular velocity was significantly different from 0, 15 degree/s condition. These results indicate that the stationarity of the EMG signals showed no difference between isometric and isokinetic conditions when the angular velocity was equal to 15 degree/s.  相似文献   
92.
Conventional advice is to reduce risky investments as one ages. Such a generalized focus on risk avoidance may be inappropriate for elderly with longer life spans and those with financial goals that extend beyond their lifetime. To better understand risky asset holdings among the elderly, we investigated the effect of cognitive ability and bequest motive on stock ownership and stock purchase. Using the 2004 wave of the Health and Retirement Study, we found that one-third of elderly households held stocks and 36% of those elderly stockowners had recently acquired stocks. The respondent??s cognitive ability and bequest motive were strongly related to stock ownership. Among those who owned stock, a bequest motive was positively related to a recent purchase of stocks.  相似文献   
93.
Studies indicate positive effects of the U.S. Vocational Rehabilitation Services (VRS) in assisting people with disabilities to find independent employment. Underemployment continues to impact access to adequate health care and other benefits. Workers with disabilities receive fewer benefits, overall. With data from the Longitudinal Study of Vocational Rehabilitation Services Program (LSVRSP), the authors compare the rates of receipt of 6 types of benefits for people with physical, mental, and sensory impairments. Although those with physical disabilities are most likely to receive benefits, all groups lack adequate access to health care, sick leave, and vacation. The authors discuss implications for services provision in the current job market.  相似文献   
94.
Lack of a valid instrument to measure learning transfer predictors has been the major obstacle hindering Human Resource Development (HRD) professionals from moving forward. This problem is one of the lingering HRD issues in South Korea, in which human resources have been strategically emphasized as a critical asset due to the scarcity of natural resources. To address this issue, this study aims at testing the validity and reliability of the data collected with the Korean Learning Transfer System Inventory (LTSI) Version 4. A sample of 753 managers from 16 Korean industries was divided into two subsamples for exploratory and confirmatory factor analyses. Reliability and the effect of common method variance on the factor structure were examined, with the results suggesting that the LTSI is valid for use in the Korean industry.  相似文献   
95.
This analysis of International Business (IB) corruption literature identifies gaps and inconsistencies in how corruption is perceived or deliberated in top academic journals. The reviewed articles tend to focus on one of the three key themes of IB corruption (Contributing factors, Consequences, and Combating) and are categorised into the six sub-domains of the IB framework. The content of the articles is categorised into the respective themes and discussed in relation to underpinning theories and key constructs. The process is intended to be less a synthesis of the literature than an audit revealing that IB corruption research is weakened by tendencies to: 1) Be siloed within its subtheme and to not cross-tie to work in other key themes—this issue is very severe in the Combating theme; 2) Have a short-term focus that disregards the cumulative effects of total graft, and; 3) Asymmetrically focus (predominantly) on the supply side of corruption. These finding suggest several avenues for further research.  相似文献   
96.
Despite the increasing evidence for the effectiveness of telehealth technology in screening and treating chronic diseases, and comorbid depression among older adults, they have been slowly adopted by home health care (HHC) agencies. Therefore, this study aimed to identify factors that determine telehealth technology adoption. Twenty directors from the National Association for Homecare & Hospice member agencies completed a 45-min telephone interview. Questions were asked regarding their perceptions of telehealth, the key determinants of telehealth adoption and use, and recommendations they would give on telehealth adoption. The majority of the participants perceived telehealth as effective for managing symptoms and reducing cost. Meanwhile, some participants had a mixed feeling toward telehealth for depression care as they did not recognize their agency as equipped with the necessary resources and trained staff. Moreover, significant determinants of telehealth adoption included the agency-related characteristics, the patient-home environment, reimbursement and cost-related factors, and staff telehealth perception. Findings imply that there is a need for financial support both at the state and the federal levels to encourage telehealth adoption among HHC agencies. Future studies should consider exploring strategies used by successful programs to overcome barriers.  相似文献   
97.
While researchers have found that African American youth experience higher levels of juvenile justice involvement at every system level (arrest, sentencing, and incarceration) relative to their other ethnic counterparts, few studies have explored how juvenile justice involvement and number of contacts might be correlated with this broad range of problems. A convenience sample of 638 African American adolescents living in predominantly low-income, urban communities participated in a survey related to juvenile justice involvement. Major findings using logistic regression models indicated that adolescents who reported juvenile justice system involvement versus no involvement were 2.3 times as likely to report mental health problems, substance abuse, and delinquent or youth offending behaviors. Additional findings documented that the higher the number of juvenile justice system contacts, the higher the rates of delinquent behaviors, alcohol and marijuana use, sex while high on drugs, and commercial sex. These findings suggest that identifying and targeting youth who have multiple juvenile justice system contacts, especially those in low-resourced communities for early intervention services, may be beneficial. Future research should examine whether peer network norms might mediate the relationships between juvenile justice involvement and youth problem behaviors.  相似文献   
98.
The Bayesian analysis based on the partial likelihood for Cox's proportional hazards model is frequently used because of its simplicity. The Bayesian partial likelihood approach is often justified by showing that it approximates the full Bayesian posterior of the regression coefficients with a diffuse prior on the baseline hazard function. This, however, may not be appropriate when ties exist among uncensored observations. In that case, the full Bayesian and Bayesian partial likelihood posteriors can be much different. In this paper, we propose a new Bayesian partial likelihood approach for many tied observations and justify its use.  相似文献   
99.
Type-I censored reliability acceptance sampling plans (RASPs) are developed for the Weibull lifetime distribution with unknown shape and scale parameters such that the producer and consumer risks are satisfied. It is assumed that the life test is conducted at an accelerated condition for which the acceleration factor (AF) is known, and each item is continuously monitored for failure. Sensitivity analyses are also conducted to assess the effect of the uncertainty in the assumed AF on the actual producer and consumer risks, and a method is developed for constructing RASPs that can accommodate the uncertainty in AF.  相似文献   
100.
Using relative utility curves to evaluate risk prediction   总被引:2,自引:0,他引:2  
Summary.  Because many medical decisions are based on risk prediction models that are constructed from medical history and results of tests, the evaluation of these prediction models is important. This paper makes five contributions to this evaluation: the relative utility curve which gauges the potential for better prediction in terms of utilities, without the need for a reference level for one utility, while providing a sensitivity analysis for misspecification of utilities, the relevant region, which is the set of values of prediction performance that are consistent with the recommended treatment status in the absence of prediction, the test threshold, which is the minimum number of tests that would be traded for a true positive prediction in order for the expected utility to be non-negative, the evaluation of two-stage predictions that reduce test costs and connections between various measures of performance of prediction. An application involving the risk of cardiovascular disease is discussed.  相似文献   
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