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821.
In the face of high staffing costs, uncertain patient arrivals, and patients unsatisfied with long wait times, staffing of medical emergency departments (EDs) is a vexing problem. Using empirical data collected from three active EDs, we develop an analytic model to provide an effective staffing plan for EDs. Patient demand is aggregated into discrete time buckets and used to model the stochastic distribution of patient demand within these buckets, which considerably improves model tractability. This model is capable of scheduling providers with different skill profiles who work either individually or in teams, and with patients of varying acuity levels. We show how our model helps to balance staffing costs and patient service levels, and how it facilitates examination of important ED staffing policies.  相似文献   
822.
Economic accounts provide a statistical picture of the economic system. The present Canadian accounts include all production that enters the market place. Additionally, the output of all enterprises, including farms, is included even though this output is not sold. Thus, the measure of output of such items does not vary according to whether such output is sold or consumed by the producer. Government activity is also included, valued at cost. The present accounts do not include household production consumed by the producing household.Two major criticisms, not unrelated, have been leveled at the existing structure of the accounts; namely, that they do not provide an adequate measuring stick for all economic activity, and that they do not provide an adequate measure of economic welfare. As a result of these criticisms there is significant agreement that a number of changes to the accounts would be desirable and perhaps more practical than had previously been contemplated.  相似文献   
823.
A regression procedure, using survey data on individual's stated preferences for communities, is used to calculate an index of ‘quality of life’. The survey instrument is extraordinarily simple, asking only for limited information about the subset of communities most well-known to respondents. The index is based upon an assumption about the distribution of the errors individuals make in perceiving the true, underlying index. The index is computed from dummy variables and is shown to have nice properties, including invariance to data ordering and (with full information) constant and equal standard errors associated with relative interplace index values. The index is estimated for a case study of 52 Pennsylvania counties.  相似文献   
824.
825.

The 1980s and 1990s have been decades of quitegood economic growth in North America and muchof Western Europe. But how have the fruits ofgrowth been shared? This paper reviews changingincome distributions in the U.S., Germany and theNetherlands. These three countries may be takenas exemplars and leading economic performers in``the three worlds of welfare capitalism''(Esping-Andersen, 1990). The U.S. is a liberalwelfare-capitalist state, Germany a corporatiststate, and the Netherlands (less clearly) asocial democratic welfare-capitalist state. Thepaper focuses particularly on income changes inthe bottom, middle and top quintiles and takesa ten year period into account.Previous analyses have shown that labor andmarket income dispersion are increasing, withincreased returns to human capital. Thepotential impact of government through thetax-transfer system has been largely ignored.All three governments redistribute income fromthe rich to the poor. However, the paper showsthat only the Dutch government hasredistributed sufficiently to ensure that thebottom quintile has gained along with others.In Germany and the U.S. the poorest quintile wasconsiderably worse off in absolute terms at theend of the decade.than the beginning. TheGerman government somewhat counteracted thetrend towards greater income dispersion byredistributing to the poorest quintile, so theloss of market income was partly compensated. In the U.S. the impact of government on thepoorest quintile stayed about the same, so thisgroup ended up with about the same decrease indisposable income as market income.The U.S., Germany and the Netherlands are theonly three countries for which ten or moreconsecutive years of panel data are available.The data come from the PSID-GSOEP EquivalentFile 1980-97 and from a comparable fileconstructed from the Dutch SEP data.

  相似文献   
826.
This paper estimates village-level models of the effects of population variables on the area devoted to upland crop production in Nang Rong district, Thailand. The expansion of upland crops is part of the growth of market agriculture in Nang Rong, and a correlate of deforestation in this setting, The results show that population density (measured as density of village settlement) negatively affects area in upland crops while population growth has a positive effect. Changes in land use associated with population change appear to radiate outward from nuclear village centers. As cash economies are established in rural settings, household formation requires a source of income as well as a subsistence stake. Growth in the population of households is a stronger predictor of the area in upland crops than growth in the number of persons.  相似文献   
827.
The purpose of this study was to validate a new interview-administered physical activity questionnaire (Assessment of Physical Activity in Frail Older People; APAFOP) in older people with and without cognitive impairment. The authors assessed feasibility, validity, and test-retest reliability in 168 people (n = 78 with, n = 88 without cognitive impairment). Concurrent validity was assessed against an inertia-based motion sensor and an established questionnaire. Sensitivity to change was tested in an ongoing study in patients with mild to moderate dementia (n = 81). Assessment of physical activity by the APAFOP and the motion sensor correlated well in the total sample (TS; p = .705), as well as in the subsamples with cognitive impairment (CI; p = .585) and without CI (p = .787). Excellent feasibility with an acceptance rate of 100%, test-retest reliability (intraclass correlation coefficients ranging from .973 (TS) to .975 (CI) to .966 (no CI), and sensitivity to change (effect sizes: 0.35-1.47) were found in both subsamples.  相似文献   
828.
The response of calf-muscle strength, resting blood flow, and postocclusive blood flow (PObf) were investigated after 4 wk of low-load resistance training (LLRT) with and without blood-flow restriction in a matched-leg design. Ten untrained older individuals age 62-73 yr performed unilateral plantar-flexion LLRT at 25% 1-repetition maximum (1RM). One limb was trained with normal blood flow and the other had blood flow restricted using a pressure cuff above the knee. 1RM, isometric maximal voluntary contraction, and isokinetic strength at 0.52 rad/s increased (p < .05) more after LLRT with blood-flow restriction than with normal blood flow. Peak PObf increased (p < .05) after LLRT with blood-flow restriction, compared with no change after LLRT with normal blood flow. These results suggest that 4 wk of LLRT with blood-flow restriction may be beneficial to older individuals to improve strength and blood-flow parameters.  相似文献   
829.
This study explored the drug resistance strategies that urban American Indian adolescents consider the best and worst ways to respond to offers of alcohol, cigarettes, and marijuana. Focus group data were collected from 11 female and 9 male American Indian adolescents attending urban middle schools in the southwest. The youth were presented with hypothetical substance offer scenarios and alternative ways of responding, based on real-life narratives of similar youth. They were asked to choose a preferred strategy, one that would work every time, and a rejected strategy, one they would never use. Using eco-developmental theory, patterns in the preferred and rejected strategies were analyzed to identify culturally specific and socially competent ways of resisting substance offers. The youth preferred strategies that included passive, non-verbal strategies like pretending to use the substance, as well as assertive strategies like destroying the substance. The strategies they rejected were mostly socially non-competent ones like accepting the substance or responding angrily. Patterns of preferred and rejected strategies varied depending on whether the offer came from a family member or non-relative. These patterns have suggestive implications for designing more effective prevention programs for the growing yet underserved urban American Indian youth population.  相似文献   
830.
The appropriateness of nursing homes for individuals with serious mental illness remains a controversial issue in long-term care policy more than a decade since the landmark U.S. Supreme Court Olmstead decision in 1999 , which affirmed the rights of persons with disabilities to live in their communities. Using national nursing home Minimum Data Set assessments from 2005, the authors compared the demographic, clinical, and functional characteristics of persons with and without serious mental illness newly admitted to nursing homes. They found that newly admitted people with serious mental illness were younger and more likely to become long-stay residents than those admitted with other conditions, despite a higher proportion of residents with serious mental illness, including the elderly, classified as low-care status. The most substantial and clinically significant difference for rates of low-care status 90 days after initial admission are for persons younger than 65 with serious mental illness versus those younger than 65 without serious mental illness (33% vs. 8.5%, or 3.9 times greater). There is a notable difference in low-care status between persons aged 65 and older with serious mental illness and those aged 65 and older without serious mental illness (14% vs. 6.6%, or 2.1 times greater). These results suggest that a substantial number of adults with serious mental illness residing in nursing homes may have the functional capacity to live in less restrictive environments.  相似文献   
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