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1.
Journal of Population Research - There is an increasing attention on the joint modelling of multiple populations. Populations are related in several ways, such as neighbouring countries, females...  相似文献   
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This article describes the metaphors persons used to describe their experiences within a three year training project in family therapy. Questions were posed of trainees that had asked them to describe their experiences of training as if they represented the title of a book, movie or journal article. Responses reveal how they construct or ‘story’ their experiences from both a first and second-order cybernetic perspective.  相似文献   
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Summary Based on 14 case studies of highly effective therapies and the reasons they succeeded less frequently than they could, we propose a variety of steps to improve the health care system of the U.S.A. Whatever proposal emerges from current national debates until innovations are shown to be safe and effective, they should not be supported; when slightly better technologies are much more expensive than other good ones we need to consider appropriate choices carefully; simplified billing and bookkeping would reduce our costs; when a technology is rapidly introduced cautionnary measures may be needed; tracking immunization and repairing their omissions requires a new system; educational programs such as seen effective in hypertension should be applied in other areas such as vaccination; in organ transplantation the nation should consider “presumed consent”; our payment system sometimes creates perverse incentives and therefore needs review; and the preferences of the public in allocation of health resources need to be discovered once the public is informed about the issues. Research supported by Andrew W. Mellon Foundation.  相似文献   
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This study evaluates the dose-response relationship for inhalation exposure to hexavalent chromium [Cr(VI)] and lung cancer mortality for workers of a chromate production facility, and provides estimates of the carcinogenic potency. The data were analyzed using relative risk and additive risk dose-response models implemented with both Poisson and Cox regression. Potential confounding by birth cohort and smoking prevalence were also assessed. Lifetime cumulative exposure and highest monthly exposure were the dose metrics evaluated. The estimated lifetime additional risk of lung cancer mortality associated with 45 years of occupational exposure to 1 microg/m3 Cr(VI) (occupational exposure unit risk) was 0.00205 (90%CI: 0.00134, 0.00291) for the relative risk model and 0.00216 (90%CI: 0.00143, 0.00302) for the additive risk model assuming a linear dose response for cumulative exposure with a five-year lag. Extrapolating these findings to a continuous (e.g., environmental) exposure scenario yielded an environmental unit risk of 0.00978 (90%CI: 0.00640, 0.0138) for the relative risk model [e.g., a cancer slope factor of 34 (mg/kg-day)-1] and 0.0125 (90%CI: 0.00833, 0.0175) for the additive risk model. The relative risk model is preferred because it is more consistent with the expected trend for lung cancer risk with age. Based on statistical tests for exposure-related trend, there was no statistically significant increased lung cancer risk below lifetime cumulative occupational exposures of 1.0 mg-yr/m3, and no excess risk for workers whose highest average monthly exposure did not exceed the current Permissible Exposure Limit (52 microg/m3). It is acknowledged that this study had limited power to detect increases at these low exposure levels. These cancer potency estimates are comparable to those developed by U.S. regulatory agencies and should be useful for assessing the potential cancer hazard associated with inhaled Cr(VI).  相似文献   
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Using data on 54,373 migrants from the Fifth Sampling Survey of the Floating Population of Shanghai, this article isolates a group of 32,967 rural labor migrants who hold rural household registrations and whose previous occupations were in agriculture, and focuses on the women among them. The demographic and occupational characteristics of these 9,124 women are described, demonstrating that migration to Shanghai is a highly gendered process, with men and women working in different occupations and sectors. Moreover, important differences are found to exist between unmarried and married female rural labor migrants that indicate that the latter are probably accompanying and working with their migrant husbands. A significant proportion of female “social” migrants also exhibit characteristics that indicate that they are the spouses of male rural labor migrants, bringing to over one third the proportion of rural labor migrants to Shanghai who could be migrating as couples. These couples and their children may be the vanguard in a transition from temporary labor migration to settlement in China's large cities.  相似文献   
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The diaspora of peoples whose origins were in the Indian subcontinent (South Asia) and who are now living in Western countries (especially the U.S. and UK) provides an interesting example of processes of negotiation of new hybrid cultures and identities, using new technologies, such as the Internet, and older technologies like the video player, cable or satellite television, radio, and telephone. These developments may require a revision of the classic sociological picture of assimilation as a zero sum model of acculturation, in which the acculturation of immigrants and their children involves the gradual replacement of their ethnic culture by that of the culture of the host nation. The electronic media, in the context of policies of multiculturalism, may lead to an accentuation of religio-ethnic differences. Contrary to previous assumptions, middle-class immigrants may be more inclined to resist cultural assimilation than their lower-class counterparts.  相似文献   
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Using cluster analysis, 789 predominately Latino and African American high school youth were classified into varying academic at‐risk profiles using self‐reported levels of academic confidence, motivation to attend school, perceived family support, connections with teachers and peers, and exposure to violence. Six clusters emerged, 5 of which were identified as “at‐risk.” The clusters were examined in relation to academic stress, health status, grades, and school retention. Exposure to violence was one distinguishing feature of youth identified as most vulnerable, vulnerable, and resilient; however, youth identified as resilient recorded better academic outcomes.  相似文献   
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Terrorist actions are aimed at maximizing harm (health, psychological, economical, and political) through the combined physical impacts of the act and fear. Immediate and effective response to a terrorist act is critical to limit human and environmental harm, effectively restore facility function, and maintain public confidence. Though there have been terrorist attacks in public facilities that we have learned from, overall our experiences in restoration of public facilities following a terrorist attack are limited. Restoration of public facilities following a release of a hazardous material is inherently far more complex than in industrial settings and has many unique technical, economic, social, and political challenges. For example, there may be a great need to quickly restore the facility to full operation and allow public access even though it was not designed for easy or rapid restoration, and critical information is needed for quantitative risk assessment and effective restoration must be anticipated to be incomplete and uncertain. Whereas present planning documents have substantial linearity in their organization, the “adaptive management” paradigm provides a constructive parallel paradigm for restoration of public facilities that anticipates and plans for uncertainty, inefficiencies, and stakeholder participation. Adaptive management grew out of the need to manage and restore natural resources in highly complex and changing environments with limited knowledge about causal relationships and responses to restoration actions. Similarities between natural resource management and restoration of a public facility after a terrorist attack suggest that integration of adaptive management principles explicitly into restoration processes will result in substantially enhanced and flexible responses necessary to meet the uncertainties of potential terrorist attacks.  相似文献   
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