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31.
The intention of this paper is to provide thescientific community with information onresearch carried out in the course of thecomparative research programme EuReporting – Towards a European System onSocial Reporting and Welfare Measurement. Thisresearch is being funded by the EuropeanCommission and is being conducted by researchteams throughout Europe. In this paper, we willreport on the findings of the research carriedout by the team in Vienna. The Vienneseresearch team is to assess the existing stockof comparative and cross-sectional surveys inthe field of social reporting and welfaremeasurement. Of concern here is not onlydocumentary work, but also the quality andcomparability of existing survey data. Thefocus of the Vienna project is upon suchcross-national and cross-sectional surveys asthe World Values Survey, the InternationalSocial Survey Programme, the Eurobarometer andthe New Democracies Barometer, as well asnational longitudinal studies.  相似文献   
32.
The aging domestic oil production infrastructure represents a high risk to the environment because of the type of fluids being handled (oil and brine) and the potential for accidental release of these fluids into sensitive ecosystems. Currently, there is not a quantitative risk model directly applicable to onshore oil exploration and production (E&P) facilities. We report on a probabilistic reliability model created for onshore exploration and production (E&P) facilities. Reliability theory, failure modes and effects analysis (FMEA), and event trees were used to develop the model estimates of the failure probability of typical oil production equipment. Monte Carlo simulation was used to translate uncertainty in input parameter values to uncertainty in the model output. The predicted failure rates were calibrated to available failure rate information by adjusting probability density function parameters used as random variates in the Monte Carlo simulations. The mean and standard deviation of normal variate distributions from which the Weibull distribution characteristic life was chosen were used as adjustable parameters in the model calibration. The model was applied to oil production leases in the Tallgrass Prairie Preserve, Oklahoma. We present the estimated failure probability due to the combination of the most significant failure modes associated with each type of equipment (pumps, tanks, and pipes). The results show that the estimated probability of failure for tanks is about the same as that for pipes, but that pumps have much lower failure probability. The model can provide necessary equipment reliability information for proactive risk management at the lease level by providing quantitative information to base allocation of maintenance resources to high-risk equipment that will minimize both lost production and ecosystem damage.  相似文献   
33.
This study examined the stability and coherence of African‐American children's social support networks. Participants included a total of 106 3‐ to 4‐year‐old children attending Head Start centers located in the southeast. Children completed a social network interview in two consecutive years at the Head Start centers. These interviews tapped multiple dimensions of the support network including social embeddedness, proportion of the network providing support, and perceived support. Analyses focused on both the rank‐order stability of children with respect to network characteristics as well as stability of network relationships (the same individuals included in the network at both time periods). Results indicated age‐related increases in network size for adult and child categories, network size across three support domains, proportion of support scores, and perceived support from adults. In addition to age‐related changes, analyses revealed considerable rank‐order stability with respect to structural network dimensions, but very little rank‐order stability in proportion of support and perceived support scores. In contrast, both structural and supportive components of the children's networks were shown to be coherent over a one‐year period when specific network member relationships were examined. Discussion highlights both continuities and discontinuities in young children's social networks, and how data obtained in this study contribute to theory building and the systematic examination of African‐American children's emerging social networks.  相似文献   
34.
A novel method was used to incorporate in vivo host–pathogen dynamics into a new robust outbreak model for legionellosis. Dose‐response and time‐dose‐response (TDR) models were generated for Legionella longbeachae exposure to mice via the intratracheal route using a maximum likelihood estimation approach. The best‐fit TDR model was then incorporated into two L. pneumophila outbreak models: an outbreak that occurred at a spa in Japan, and one that occurred in a Melbourne aquarium. The best‐fit TDR from the murine dosing study was the beta‐Poisson with exponential‐reciprocal dependency model, which had a minimized deviance of 32.9. This model was tested against other incubation distributions in the Japan outbreak, and performed consistently well, with reported deviances ranging from 32 to 35. In the case of the Melbourne outbreak, the exponential model with exponential dependency was tested against non‐time‐dependent distributions to explore the performance of the time‐dependent model with the lowest number of parameters. This model reported low minimized deviances around 8 for the Weibull, gamma, and lognormal exposure distribution cases. This work shows that the incorporation of a time factor into outbreak distributions provides models with acceptable fits that can provide insight into the in vivo dynamics of the host‐pathogen system.  相似文献   
35.
Recreational and subsistence angling are important aspects of urban culture for much of North America where people are concentrated near the coasts or major rivers. Yet there are fish and shellfish advisories for many estuaries, rivers, and lakes, and these are not always heeded. This paper examines fishing behavior, sources of information, perceptions, and compliance with fishing advisories as a function of ethnicity for people fishing in the Newark Bay Complex of the New York–New Jersey Harbor. We test the null hypothesis that there were no ethnic differences in sources of information, perceptions of the safety of fish consumption, and compliance with advisories. There were ethnic differences in consumption rates, sources of information about fishing, knowledge about the safety of the fish, awareness of fishing advisories or of the correct advisories, and knowledge about risks for increased cancer and to unborn and young children. In general, the knowledge base was much lower for Hispanics, was intermediate for blacks, and was greatest for whites. When presented with a statement about the potential risks from eating fish, there were no differences in their willingness to stop eating fish or to encourage pregnant women to stop. These results indicate a willingness to comply with advisories regardless of ethnicity, but a vast difference in the base knowledge necessary to make informed risk decisions about the safety of fish and shellfish. Although the overall median income level of the population was in the $25,000–34,999 income category, for Hispanics it was on the border between $15,000–24,999 and $25,000–34,999.  相似文献   
36.
Abstract Temporary visa workers are increasingly taking on a heightened profile in Canada, entering the workforce each year in greater numbers than immigrant workers with labor mobility rights (Sharma 2006). This paper examines the incorporation of foreign workers in Canadian horticulture under the Seasonal Agricultural Workers Program (SAWP). I argue that foreign labor supplied under the SAWP secures a flexible workforce for employers and thus improves Canada's trade competitiveness in the global agrifood market. Using multiple research strategies, I track the evolution of Canadian horticulture in the global market and the transformation of labor in this industry. I outline the steady growth in the employment of temporary visa workers in the horticultural industry and show how they have become the preferred and, in some cases, core workforce for horticulture operations. The benefits of SAWP workers to employers include the provision of a workforce with limited rights relative to domestic workers and considerable administrative support in selecting, dispatching, and disciplining workers provided at no cost by labor supply countries. I conclude that the SAWP is a noteworthy example of the role of immigration policy in regulating the labor markets of high‐income economies and thus ensuring the position of labor‐receiving states within the global political economy.  相似文献   
37.
While migration in South Africa has been studied on a broad canvas, there have been few accounts of children's migration and the effects on living conditions and wellbeing. This article compares the access to services, housing and household amenities, and family characteristics of children born in the Greater Johannesburg metropolis with those of in-migrant children. The article also examines other indicators of child wellbeing related to parental care and schooling. In-migrant children, particularly children who have lived previously in rural areas and/or have recently migrated into the city, are significantly disadvantaged in comparison to long-term resident children in terms of parental education and occupation, housing type and ownership, access to electricity, refuse removal, water and sanitation. In-migrant children also live in households that are less likely to have amenities such as a refrigerator, television, washing machine, telephone and motor vehicle. In terms of child indicators, in-migrant children enjoy less frequent parental contact and are twice as likely to start school later than resident children. Whilst urbanisation to South Africa's metropolitan centres is generally associated with several widely recognised benefits, for children, these benefits may be tempered by the disadvantages of in-migrant families known to be associated with child wellbeing.  相似文献   
38.
A conclusive story can be made out of equal absolute and equal proportional sacrifice rules if only income after some poll tax of equal total revenue is taken as basis for distributional comparisons.  相似文献   
39.
40.
Estimates of soil adherence to skin are required for assessment of dermal exposures to contaminants in soils. Previously available estimates depend heavily on indirect measurements and/or artificial activities and reflect sampling of hands only. Results are presented here from direct measurement of soil loading on skin surfaces of volunteers before and after normal occupational and recreational activities that might reasonably be expected to lead to soil contact. Skin surfaces assayed included hands, forearms, lower legs, faces and/or feet. Observed hand loadings vary over five orders of magnitude (roughly from 10–3 to 102 mg/cm2) and are dependent upon type of activity. Hand loadings within the current default range of 0.2 to 1.0 mg/cm2 were produced by activities providing opportunity for relatively vigorous soil contact (rugby, farming). Loadings less than 0.2 mg/cm2 were found on hands following activities presenting less opportunity for direct soil contact (soccer, professional grounds maintenance) and on other body parts under many conditions. The default range does not, however, represent a worst case. Children playing in mud on the shore of a lake generated geometric mean loadings well in excess of 1 mg/cm2 on hands, arms, legs, and feet. Post-activity average loadings on hands were typically higher than average loadings on other body parts resulting from the same activity. Hand data from limited activities cannot, however, be used to conservatively predict loadings that might occur on other body surfaces without regard to activity since non-hand loadings attributable to higher contact activities exceeded hand loadings resulting from lower contact activities. Differences between pre- and post-activity loadings also demonstrate that dermal contact with soil is episodic. Typical background (pre-activity) geometric mean loadings appear to be on the order of 10-2 mg/cm2 or less. Because exposures are activity dependent, quantification of dermal exposure to soil will remain inadequate until data describing relevant human behavior (type of activity, frequency, duration including interval before bathing, clothing worn, etc.) are generated.  相似文献   
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