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31.
Compliance Versus Risk in Assessing Occupational Exposures   总被引:1,自引:0,他引:1  
Assessments of occupational exposures to chemicals are generally based upon the practice of compliance testing in which the probability of compliance is related to the exceedance [γ, the likelihood that any measurement would exceed an occupational exposure limit (OEL)] and the number of measurements obtained. On the other hand, workers’ chronic health risks generally depend upon cumulative lifetime exposures which are not directly related to the probability of compliance. In this paper we define the probability of “overexposure” (θ) as the likelihood that individual risk (a function of cumulative exposure) exceeds the risk inherent in the OEL (a function of the OEL and duration of exposure). We regard θ as a relevant measure of individual risk for chemicals, such as carcinogens, which produce chronic effects after long-term exposures but not necessarily for acutely-toxic substances which can produce effects relatively quickly. We apply a random-effects model to data from 179 groups of workers, exposed to a variety of chemical agents, and obtain parameter estimates for the group mean exposure and the within- and between-worker components of variance. These estimates are then combined with OELs to generate estimates of γ and θ. We show that compliance testing can significantly underestimate the health risk when sample sizes are small. That is, there can be large probabilities of compliance with typical sample sizes, despite the fact that large proportions of the working population have individual risks greater than the risk inherent in the OEL. We demonstrate further that, because the relationship between θ and γ depends upon the within- and between-worker components of variance, it cannot be assumed a priori that exceedance is a conservative surrogate for overexposure. Thus, we conclude that assessment practices which focus upon either compliance or exceedance are problematic and recommend that employers evaluate exposures relative to the probabilities of overexposure.  相似文献   
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Monk parakeets (Myiopsitta monachus) are the most abundant and widely distributed of the naturalized parrots in the United States. Their presence is simultaneously encouraged by some humans (through use of bird feeders) and discouraged by others (through removal of their nests) and, as a result, they show an interesting spatial distribution across urban areas. We used an online public survey and field surveys to examine the influence of human activities and land use on the distribution of this exotic species around Chicago, IL (USA). These efforts resulted in detection of 249 nesting structures and approximately 778 birds across the region. A CART analysis successfully separated nesting sites from random sites and correctly classified 90?% of the nesting sites. The most important factor in the model was land use, with nests typically found in areas with less than 84?% residential zoning. We found nests on a wide variety of substrates including trees, cell phone towers, and stadium lights. Spatial point pattern analysis indicated that nests in trees and nests in built substrates were significantly dissociated with each other at all scales. Nests on built substrates were closer to railroads and highways or in areas with lower human population density, suggesting either a difference in substrate availability or human tolerance between these settings. While humans may have a positive effect on distribution of monk parakeets at large spatial scales, at the scale of this study we see a potentially negative effect of too many humans on the distribution of monk parakeet nests.  相似文献   
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An approach is presented for strengthening middle school standards‐based English language arts (ELA) classroom instruction by infusing theory‐ and research‐supported career development constructs and practices. Over an 8‐week period, 90 urban 7th graders participated in an integrated ELA–career development curriculum. Career agency emerged as an important construct for students. It was related to key markers of ELA achievement (i.e., standardized test scores, grades, and positive change in 6th‐ to 7th‐grade test scores) and elaborated on in nuanced ways by students in their written narratives. Four themes related to career agency were identified in student writings: time perspective, challenges of self‐direction, career development, and social and emotional development. Advantages for students and schools related to synergy, scale, and sustainability are discussed.  相似文献   
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In late 2009 China launched an innovative, voluntary programme that by 2011 had extended pension coverage to 326.4 million people in the rural sector, including contributors and beneficiaries. It requires one contribution per year and provides a flat‐rate benefit and a contributions‐related benefit through a contributory individual account, with a government guarantee that the benefit will continue for life. The programme encourages participation of persons who do not pay income taxes, and thus have no tax incentive to participate, by providing substantial government subsidies. As a further incentive, old‐age benefits are provided to older parents when all their adult children participate in the contributory programme.  相似文献   
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The author integrated attachment theory with social cognitive career theory (SCCT) to examine how attachment styles influence the career search self‐efficacy activities of interviewing, networking, job searching, and personal exploration. Using an undergraduate sample (N = 275, 81% women), the author tested a structural model. Results indicated that anxious attachment style was negatively related to interviewing self‐efficacy, whereas avoidant attachment style was negatively related to networking, job searching, and personal exploration self‐efficacy. Theoretical implications based on these findings provide support for an integrative model of attachment theory with SCCT. Career counselors are encouraged to consider clients’ attachment styles when working with individuals who are searching for employment. To help address the limitations of the study, future researchers could test the applicability of the current model with a more diverse sample.  相似文献   
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Consumer culture and neoliberal political economy are often viewed by social psychologists as topics reserved for anthropologists, economists, political scientists and sociologists. This paper takes an alternative view arguing that social psychology needs to better understand these two intertwined institutions as they can both challenge and provide a number of important insights into social psychological theories of self‐identity and their related concepts. These include personality traits, self‐esteem, social comparisons, self‐enhancement, impression management, self‐regulation and social identity. To illustrate, we examine how elements of consumer culture and neoliberal political economy intersect with social psychological concepts of self‐identity through three main topics: ‘the commodification of self‐identity’, ‘social categories, culture and power relations’ and the ‘governing of self‐regulating consumers’. In conclusion, we recommend a decommodified approach to research with the aim of producing social psychological knowledge that avoids becoming enmeshed with consumer culture and neoliberalism.  相似文献   
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Statistics and Computing - To overcome the inherent limitations of axis-aligned base learners in ensemble learning, several methods of rotating the feature space have been discussed in the...  相似文献   
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