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61.
Abstract Previous models of community satisfaction and attachment have not included personal economic attitudes and behaviors as independent variables. Their inclusion is theoretically justified when residents of communities are viewed as consumers in a larger social/economic context first and residents of a particular community second. As locally-oriented economic processes—once part of the community experience—were removed to nonlocal markets, local economic and demographic attributes became less important to rural residents' experience of community. In two rural communities with extreme scores on a service center viability index, satisfaction with employment and location of employment are important predictors.  相似文献   
62.
63.
Two assumptions used in risk assessment are investigated: (1) the assumption of fraction of lifetime dose rate assumes that the risk from a fractional lifetime exposure at a given dose rate is equal to the risk from full lifetime exposure at that same fraction of the given dose rate; (2) the assumption of fraction of lifetime risk assumes that the risk from a fractional lifetime exposure at a given dose rate is equal to that same fraction of the risk from full lifetime exposure at the same dose rate. These two assumptions are equivalent when risk is a linear function of dose. Thus both can be thought of as generalizations of the assumption that cancer risk is proportional to the total accumulated lifetime dose (or average daily dose), which is often made to assess the risk from short-term exposures. In this paper, the age-specific cumulative hazard functions are derived using the two-stage model developed by Moolgavkar, Venzon, and Knudson for situations when the exposure occurs during a single period or a single instant. The two assumptions described above are examined for three types of carcinogens, initiator, completer, and promoter, in the context of the model. For initiator and completer, these two assumptions are equivalent in the low-dose region; for a promoter, using the fraction of lifetime risk assumption is generally more conservative than that of the fraction of lifetime dose rate assumption. Tables are constructed to show that the use of either the fraction of lifetime dose rate assumption or the fraction lifetime risk assumption can both underestimate and overestimate the true risk for the three types of carcinogens.  相似文献   
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65.
A nonparametric estimator of the probability distribution of time-to-tumor is incorporated into an algorithm for calculating linearly extrapolated dosage limits from an animal carcino-genesis bioassay. The procedure is illustrated with tumor data from a mouse bioassay with 2-acetylaminofluorene. Extrapolated dosage limits for an excess risk of 10-6 differ by only a factor of 2 across the six replicates of the experiment.  相似文献   
66.
Ralph L Hopps 《Omega》1973,1(3):359-361
The paper discusses the problems involved in staffing a large, labour-intensive clearing bank. The three basic objectives of maintaining sufficient staff numbers of the required type, offering them satisfactory career prospects within a pyramid structure, and containing costs, create conflicts which need to be resolved.  相似文献   
67.
Most models of modernization propose that the status of the aged declines with technological and economic development. These models usually conceptualize the lowered status of the aged as a residual or latent consequence of modernization. Rarely do they address age stratification as a political issue, and they fail to differentiate between subgroups of the aged. We compare accounts of the cultural and structural context of the aged before and after China's socialist revolution, giving particular attention to the role of the family, the state, and technological factors in social change. Technological development and urbanization have not been extensive, and a decline in the traditional authority of the aged has paralleled educational advances and a demographic transition. Government family policies and China's labor-intensive economy facilitate the interdependence of age groups and sex roles. These observations suggest current models of the status of the aged should be revised to incorporate conceptualizations of age and sexual stratification and the role of governmental policies in directing social change.  相似文献   
68.
This is a case study of the Employed Girls Society, a voluntary association which was organized in 1929 as a training vehicle for young working women and which functions today as an old age support system. A vestige of the past, the EGS is also an omen of the future; current demographic and economic trends portend a time when clubs like the EGS will be required, more and more, to meet the needs of a burgeoning aged population.  相似文献   
69.
Ralph H Sprague  Jr  Hugh J Watson 《Omega》1976,4(6):657-671
Just recently, information systems with rather unique characteristics have begun to emerge. These systems usually referred to as Decision Support Systems, feature decision models, a data base and the decision maker as subsystems and are specifically oriented to supporting decision making. This article examines Decision Support Systems and their application to banks.  相似文献   
70.
Evaluation of teaching at universities is traditionally realized in terms of student ratings. Curriculum evaluation is rarely done in a systematic manner. More often, the emphasis is placed on a particular aspect, which is only of little help in terms of modifying education. A very prominent example is that of medical education. Here, evaluations of curricula primarily focus on new curricula by contrasting them to traditional ones. The article at hand deals with a different evaluation approach, in which five phases have to be considered and contrasting results to other teaching formats are not the main focus. In this article, the authors concentrate on the first phase (baseline evaluation) of the systematic evaluation of a medical curriculum. They describe several challenges of such an evaluation approach and illustrate the strategies used to overcome them. In addition, associated relevant empirical findings from this evaluation study are presented.  相似文献   
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