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951.
OBJECTIVE: Our objective was to develop an organized system to assess individual and group exposure to animal hazards on a college campus. MAIN POINTS: The scope and complexity of college health services continue to expand as campuses confront unforeseen exposures and disease entities. Of great concern are students and faculty who are exposed to potentially life threatening and other serious conditions during their academic work. CONCLUSION: A college health service developed an effective animal-hazard surveillance questionnaire that could be scanned and analyzed for individual and group exposure to hazards and the presence or absence of protective measures. The college then provided appropriate preventive services. 相似文献
952.
Doldo NA Delmonico MJ Bailey JA Hand BD Kostek MC Rabon-Stith KM Menon KS Conway JM Carignan CR Hurley BF 《Journal of aging and physical activity》2006,14(4):411-422
To determine sex and race differences in muscle power per unit of muscle contraction, knee-extensor muscle power normalized for knee-extensor muscle volume was measured in 79 middle-aged and older adults (30 men and 49 women, age range 50-85 years). Results revealed that women displayed a 38% faster peak movement velocity than men and African Americans had a 14% lower peak movement velocity than Whites of a similar age when expressed per unit of involved muscle (p < .001). As expected, men exhibited greater knee-extensor strength and peak power per unit of muscle than women, but women had a faster knee- extension movement velocity per unit of muscle than men at the same relative strength level. Moreover, African Americans had greater knee-extensor muscle volume than Whites but exhibited lower knee-extensor strength and lower movement velocity per unit of muscle when tested at the same relative strength levels. 相似文献
953.
Reneman MF Kuijer W Brouwer S 《Work (Reading, Mass.)》2006,26(2):229; author reply 231-229; author reply 233
954.
Reese DJ Raymer M Orloff SF Gerbino S Valade R Dawson S Butler C Wise-Wright M Huber R 《Journal of social work in end-of-life & palliative care》2006,2(2):65-95
This paper reports on the last of three National Hospice and Palliative Care Organization initiatives to move hospice and palliative care social workers into the patient/family outcomes arena: the development of the Social Work Assessment Tool. The experience of a team of practitioners and researchers is described, including results of two pilot studies and subsequent SWAT revisions. The major focus is on the current model performance improvement project, in which 19 social workers from 14 hospice and palliative care programs used the SWAT with 101 patients and 81 primary caregivers for a median of 44 days. Quantitative analysis indicated significant improvement in SWAT scores for patients from the first to the second social work visit (t = -2.60, df = 47, p .01). Qualitative interviewing of the social workers indicated some lack of readiness in the field to conduct quantitative outcomes measurement. Additional measures are needed in addition to the SWAT, including qualitative measures, and measures of mezzo and macro practice. Participants indicated that the SWAT was appropriate for use with economically and culturally diverse clients. 相似文献
955.
In make‐to‐stock production systems finished goods are produced in anticipation of demand. By contrast, in stockless production systems finished goods are not produced until demand is observed. In this study we investigate the problem of designing a multi‐item manufacturing system, where there is both demand‐ and production‐related uncertainty, so that stockless operation will be optimal for all items. For the problem of interest, we focus on gaining an understanding of the effect of two design variables: (i) manufacturing speed—measured by the average manufacturing rate or, equivalently, the average unit manufacturing time, and (ii) manufacturing consistency—measured by the variation in unit manufacturing times. We establish conditions on these two variables that decision makers can use to design stockless production systems. Managerial implications of the conditions are also discussed. 相似文献
956.
Juan F. Escobar Juuso Toikka 《Econometrica : journal of the Econometric Society》2013,81(5):1887-1934
We study repeated Bayesian games with communication and observable actions in which the players' privately known payoffs evolve according to an irreducible Markov chain whose transitions are independent across players. Our main result implies that, generically, any Pareto‐efficient payoff vector above a stationary minmax value can be approximated arbitrarily closely in a perfect Bayesian equilibrium as the discount factor goes to 1. As an intermediate step, we construct an approximately efficient dynamic mechanism for long finite horizons without assuming transferable utility. 相似文献
957.
Nicholas Bloom Mark Schankerman John Van Reenen 《Econometrica : journal of the Econometric Society》2013,81(4):1347-1393
The impact of R&D on growth through spillovers has been a major topic of economic research over the last thirty years. A central problem in the literature is that firm performance is affected by two countervailing “spillovers” : a positive effect from technology (knowledge) spillovers and a negative business stealing effects from product market rivals. We develop a general framework incorporating these two types of spillovers and implement this model using measures of a firm's position in technology space and productmarket space. Using panel data on U.S. firms, we show that technology spillovers quantitatively dominate, so that the gross social returns to R&D are at least twice as high as the private returns. We identify the causal effect of R&D spillovers by using changes in federal and state tax incentives for R&D. We also find that smaller firms generate lower social returns to R&D because they operate more in technological niches. Finally, we detail the desirable properties of an ideal spillover measure and how existing approaches, including our new Mahalanobis measure, compare to these criteria. 相似文献
958.
20世纪70年代以来,多国公司寻求在世界范围内安排其生产经营活动,于是多国公司成为全球化的支持者和主体;而全球化的反对者认为在世界一体化迅速发展的同时,许多国家不再能够采取主权国家政策,尤其是在社会保障方面。不同国家对于全球化的态度不尽相同,但是某些国家却把其面临的经济困境归咎于全球化。相反,本文表明,国家对国际贸易的开放为国家经济的发展提供了更多选择,并且是解决许多国家在2 0世纪70~80年代遭遇的经济困难的良方。因此,许多发达国家和发展中国家不同程度地扩大了开放。文章指出了国家的公共政策是促进全球化的积极影响… 相似文献
959.
F. P. A. Coolen P. Coolen-Schrijner T. Coolen-Maturi F. F. Elkhafifi 《统计学通讯:理论与方法》2013,42(19):3478-3496
Nonparametric predictive inference (NPI) is a powerful frequentist statistical framework based only on an exchangeability assumption for future and past observations, made possible by the use of lower and upper probabilities. In this article, NPI is presented for ordinal data, which are categorical data with an ordering of the categories. The method uses a latent variable representation of the observations and categories on the real line. Lower and upper probabilities for events involving the next observation are presented, and briefly compared to NPI for non ordered categorical data. As application, the comparison of multiple groups of ordinal data is presented. 相似文献
960.
We reconsider the derivation of Blest’s (2003) skewness adjusted version of the classical moment-based coefficient of kurtosis and propose an adaptation of it which generally eliminates the effects of asymmetry a little more successfully. Lower bounds are provided for the two skewness adjusted kurtosis moment measures as functions of the classical coefficient of skewness. The results from a Monte Carlo experiment designed to investigate the sampling properties of numerous moment-based estimators of the two skewness adjusted kurtosis measures are used to identify those estimators with lowest mean squared error for small to medium sized samples drawn from distributions with varying levels of asymmetry and tailweight. 相似文献