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871.
Fritz Jan Marie Bistak Paula Auffrey Christopher 《Sociological Practice: A Journal of Clinical and Applied Sociology》2000,2(2):113-126
Over 880 communities have put regulations in place to reduce or eliminate tobacco use in buildings used by the public. This study examines the experience of one such community—Well City, Ohio. The nonsmoker protection efforts in Well City help us identify and discuss eight important considerations affecting policy development and implementation: (1) anticipate community opposition, (2) identify and collaborate with a support network, (3) control the community hearing process, (4) anticipate outside interests, (5) recognize the potential for legal challenges, (6) address life with legal limbo, (7) start strong, and (8) watch the mix of politics and public health. Current clean indoor air efforts seem to focus on establishing coalitions and encouraging employers to voluntarily establish tobacco-free workplaces and restaurants. These efforts certainly need to continue but as a basic part of a comprehensive program which recognizes the importance and fosters the development of strong nonsmoker protection regulations developed at the local level by health boards, county boards of supervisors, and/or city councils. 相似文献
872.
Headwater streams are in close contact with the landscape and known to mediate disturbances to downstream waterways through important ecological interactions. We studied how elevated chloride from road deicer, a pollutant of rising concern in urban ecosystems, influenced the leaf-microbial matrix in streams, and subsequent processing of C and N. In a multi-factorial laboratory experiment, we determined if elevated chloride interacts with nitrogen loading and invertebrate consumer feeding to alter rates of leaf litter breakdown and N immobilization. Naturally colonized leaf litter, the dominant C source in small streams, was collected from five Piedmont streams (Maryland, USA) and subjected to a gradient of NaCl (0, 1,000, 5,000?mg Cl l?1) and dissolved nitrogen (ambient, elevated), and an invertebrate treatment (presence, absence) in a total of 60 microcosms. Loss rate and C:N content were determined from remaining leaf litter after 16 d of incubation. Chloride loading significantly (P?<?0.05) reduced loss rate regardless of N loading, and C:N content significantly (P?<?0.05) increased with Cl concentration, interacting marginally (P?<?0.10) with N loading. Invertebrate feeding had a marginally-significant (P?<?0.10), negative effect on loss rate, but not C:N content. Overall, elevated chloride significantly influenced organic matter loss rate and N immobilization, despite N loading and the presence of invertebrates. We conclude that there is the potential for chloride loading as road deicer runoff to negatively influence microbial processing of C and N by stream-dwelling microbial communities. 相似文献
873.
Christopher T. Fennell 《Infancy》2012,17(3):339-353
Infants greatly refine their ability to discriminate language sounds by 12 months, yet 14‐month‐olds appear to confuse similar‐sounding novel words. Two explanations could account for this phenomenon: infants initially have incomplete phoneme representations, suggesting developmental discontinuity; or word‐learning demands interfere with use of established phonetic detail. These hypotheses were tested at 14 months by pairing a novel word with an object preexposed to half the infants and novel to the other half. If demands are key, only preexposed infants should efficiently use phonetic detail; there is no need to concurrently learn object details with the word. If representations lack detail, object familiarity should not matter. Only infants preexposed to the object noticed a change in its label, thus challenging the discontinuity position and demonstrating the impact of object familiarity on early word learning. 相似文献
874.
Bradley A. Jones William Li Christopher J. Nachtsheim Kenny Q. Ye 《Journal of statistical planning and inference》2009
Supersaturated designs are an increasingly popular tool for screening factors in the presence of effect sparsity. The advantage of this class of designs over resolution III factorial designs or Plackett–Burman designs is that n, the number of runs, can be substantially smaller than the number of factors, m. A limitation associated with most supersaturated designs produced thus far is that the capability of these designs for estimating g active effects has not been discussed. In addition to exploring this capability, we develop a new class of model-robust supersaturated designs that, for a given n and m, maximizes the number g of active effects that can be estimated simultaneously. The capabilities of model-robust supersaturated designs for model discrimination are assessed using a model-discrimination criterion, the subspace angle. Finally, we introduce the class of partially supersaturated designs, intended for use when we require a specific subset of m1 core factors to be estimable, and the sparsity of effects principle applies to the remaining (m-m1) factors. 相似文献
875.
Ian L. Dryden Li Bai Christopher J. Brignell Linlin Shen 《Statistics and Computing》2009,19(3):229-238
A dimension reduction technique is proposed for matrix data, with applications to face recognition from images. In particular,
we propose a factored covariance model for the data under study, estimate the parameters using maximum likelihood, and then
carry out eigendecompositions of the estimated covariance matrix. We call the resulting method factored principal components
analysis. We also develop a method for classification using a likelihood ratio criterion, which has previously been used for
evaluating the strength of forensic evidence. The methodology is illustrated with applications in face recognition. 相似文献
876.
In this paper, principal components methodology is used to derive simplified and cost effective indexes of water poverty.
Using a well known data set for 147 countries from which an earlier five-component water poverty index comprising of Resources, Access, Capacity, Use and Environment was constructed, we find that a simplified three-component composite index comprising of Access, Capacity, and Environment, with unequal weights, or its two-component counterpart comprising of Capacity and Environment with equal weights, would be more cost-effective to construct without much loss of information. These simplified indexes
have high positive and negative correlations with the Human Development Index and the Human Poverty Index, respectively. 相似文献
877.
878.
J. Allen Williams Jr. Christopher Podeschi Nathan Palmer Philip Schwadel Deanna Meyler 《Sociological inquiry》2012,82(1):145-159
Picture books often play an important role in childhood socialization. Given the seriousness of environmental problems, we ask how natural, modified, and built environments have been portrayed in children’s books. To answer this question, we analyze the 296 books receiving Caldecott awards from 1938 to 2008. Two possibilities are explored with respect to content change. Growing concern about critical environmental problems, such as decline in biodiversity and deforestation, may have led to an increase in illustrations and stories about wild animals and the natural environment. Alternatively, the increasing isolation of people from the natural world may have resulted in a decline in the perceived relevance of these environmental issues and resulted in fewer stories and depictions. Our findings support the isolation hypothesis. There have been significant declines in depictions of natural environments and animals while built environments have become much more common. These findings suggest that today’s generation of children are not being socialized, at least through this source, toward an understanding and appreciation of the natural world and the place of humans within it. 相似文献
879.
Schuh RG Tony Eichelberger R Stebbins S Pomer B Duran L Mahoney JF Keane C Lin CJ Potter MA 《Evaluation and program planning》2012,35(4):473-480
Local public health agencies often must respond to health-related emergencies or disasters, while continuing to fulfill all public health functions for which they are funded. This article reports the development and initial pilot test of a method for measuring the nature and degree of a public health agency's response to such an emergency or disaster. How the instrument was developed as well as the initial results from the pilot study of four local public health systems (LPHSs) are presented and discussed. The instrument measured the extent to which each function and division of each of the four LPHSs were affected and provided a metric that could be used across LPHSs to indicate the burden experienced by each due to the emergency. Results obtained from the pilot study indicate that size and complexity of an LPHS was not predictive of its ability to respond to the emergency. These results support the use of the framework and associated measurement procedures to provide valuable information to managers responsible for such LPHSs. Such information should provide a foundation for comparing variations in performance and outcomes to various types of emergencies that vary in their severity and focus. 相似文献
880.
Intimate partner victimization among adults aged 60 and older: an analysis of the 1999 and 2004 General Social Survey 总被引:1,自引:0,他引:1
Accounts in both the scientific literature and popular media have brought about increased recognition of the reality of elder abuse. However, relatively little work has examined intimate partner victimization with respect to older adults. In this study, weighted data from cycles 13 (1999) and 18 (2004) of the General Social Survey are pooled to examine how factors uniquely influence the prevalence and risk of emotional, financial, and physical abuse among adults aged 60 and over. Considerations regarding elder abuse committed by spouses, versus abuse of older adults more broadly (by their children and other adults), are also discussed. 相似文献