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81.
The presence of erm genes was investigated among macrolide-resistant Gram-positive bacteria isolated from soil samples collected from four Danish farms that had been treated with animal waste. Soil samples were collected before, a few days after spread and 1 1/2 months and 5 months later. In 33% (9/27) of these isolates, an erm gene was detected using PCR. Eight isolates were positive for erm(B) and one isolate was positive for erm(C). No isolates contained erm(A), erm(D) or erm(F). The positive isolates were identified to genus level. Two erm(B) positive isolates were identified as Enterococcus spp., and the erm(C)-positive isolate as a Streptococcus spp., probably indicating survival from animal waste. The remaining six erm(B) positive isolates all belonged to the Bacillus cereus group. The erm(B) gene has not previously been identified in B. cereus but is frequently found among enterococci. This result could indicate horizontal transfer from bacteria of animal origin to indigenous soil bacteria. 相似文献
82.
Public Participation and Local Environmental Planning: the collective action problem and the potential of social capital 总被引:2,自引:0,他引:2
Expanding the opportunities for public participation in environmental planning is not always the best option. Starting from an institutional public choice analysis of public participation in terms of the collective action problem, this paper emphasises the roots of participatory activities in the incentive structures facing potential participants. It then goes on to consider the strategies that may be adopted for encouraging greater public involvement and looks particularly to the social capital literature for suggestions of how institutional redesign may alter these incentive structures. The paper concludes by distinguishing three different modes of environmental planning, in terms of the rationale for participation, the severity of the collective action problem and the associated participatory strategy that can be adopted. 相似文献
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Radboud J. Duintjer Tebbens Marita Zimmermann Mark A. Pallansch Kimberly M. Thompson 《Food and environmental virology》2017,9(4):361-382
Poliovirus surveillance plays a critical role in achieving and certifying eradication and will play a key role in the polio endgame. Environmental surveillance can provide an opportunity to detect circulating polioviruses prior to the observation of any acute flaccid paralysis cases. We completed a systematic review of peer-reviewed publications on environmental surveillance for polio including the search terms “environmental surveillance” or “sewage,” and “polio,” “poliovirus,” or “poliomyelitis,” and compared characteristics of the resulting studies. The review included 146 studies representing 101 environmental surveillance activities from 48 countries published between 1975 and 2016. Studies reported taking samples from sewage treatment facilities, surface waters, and various other environmental sources, although they generally did not present sufficient details to thoroughly evaluate the sewage systems and catchment areas. When reported, catchment areas varied from 50 to over 7.3 million people (median of 500,000 for the 25% of activities that reported catchment areas, notably with 60% of the studies not reporting this information and 16% reporting insufficient information to estimate the catchment area population size). While numerous studies reported the ability of environmental surveillance to detect polioviruses in the absence of clinical cases, the review revealed very limited information about the costs and limited information to support quantitative population effectiveness of conducting environmental surveillance. This review motivates future studies to better characterize poliovirus environmental surveillance systems and the potential value of information that they may provide in the polio endgame. 相似文献
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PROBLEM: There are no specific indicators for distinguishing insurance claims related to speeding and impaired driving in the information warehouse at the Insurance Corporation of British Columbia. Contributing factors are only recorded for that part of the claim data that is also reported by the police. Most published statistics on crashes that are related to alcohol or speeding are based on police-reported data, but this represents only a fraction of all incidents. METHOD: This paper proposes surrogate models to estimate the counts and the average costs associated with speeding and impaired driving to insurance claims when contributing factors are unknown. Using police-reported data, classification rules and logistic regression models are developed to form such estimates. One approach applies classification rules to categorize insurance claims into those related to speeding, impaired driving, and other factors. The counts and the costs of insurance claims for each of these strata and overall are then estimated. A second method models the probability that an insurance claim is related to speeding or impaired driving using logistic regression and uses this to estimate the overall counts and the average costs of the claims. The two methods are compared and evaluated using simulation studies. RESULTS: The logistic regression model was found to be superior to the classification model for predicting insurance claim counts by category, but less efficient at predicting average claim costs. IMPACT: Having estimates of counts and costs of insurance claims related to impaired driving or speeding for all reported crash events provides a more accurate basis for policy-makers to plan changes and benefits of road safety programs. 相似文献
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INTRODUCTION: Logistic regression modelling of crash counts likely associated with speeding and impaired driving was earlier found [Zheng, Y., Cooper, P. J., & Dean, C. B. (2007). Modeling the contribution of speeding and impaired driving to insurance claim counts and costs when contributing factors are unknown. Journal of Safety Research, 38(1)] to successfully predict known outcomes in a series of simulations, but the same types of models did not accurately predict average crash costs. The aim of the study reported here was to develop a means to adjust classification model results that would improve their cost-predicting efficiency. METHOD: A classification modelling process was adjusted at the back-end using non-linear optimization to rationalize the classified proportions with the true proportions when the model was applied to representative subsets of the training data. Corrections were developed to account for cost (severity) differences arising from the classification process that were not due to true variations. The process was then applied to insurance claim test data where crash contributors were unknown. RESULTS: The optimization and severity correction procedure resulted in substantial improvement in average crash cost prediction for both impaired and unsafe speed collision involvements. The error measured against true values in 20 simulations was about half for the adjusted classification model of what it was for either unadjusted classification or logistic regression models. CONCLUSIONS: Non-linear optimization of classification matrices appears to be a workable tool for improving the predictive efficiency of models where desired outcomes represent average characteristics of records as compared to simple counts or proportions. IMPACT ON INDUSTRY: Using the methodology on a full-year of insurance claim data indicated that reliance on police-reported records alone would have underestimated the total cost of unsafe speed and impaired crashes by about 40%. Since most jurisdictions use police data to base policy decisions and set program spending around such safety issues, this finding has important implications. 相似文献
89.
Magalie Castelin Pierre Feutry Mélyne Hautecoeur Gérard Marquet Daisy Wowor Gabrielle Zimmermann Philippe Keith 《Marine Biology》2013,160(6):1395-1406
Due to the sparse and unstable nature of insular freshwater habitats, marine larval dispersal of amphidromous species is considered a critical element of population persistence. We assessed population genetic structure of freshwater prawn Macrobrachium lar across its range that encompasses two biogeographic barriers: the vast open ocean separating Western and Central Pacific regions and the Indo-Malay archipelago separating Indian and Pacific oceans. A total of 173 samples collected from 21 islands throughout the Indo-Pacific were sequenced at 16S and 28S rDNA. We observed distinct genetic isolation of populations located at the eastern and southwestern edge of the species range but no evidence of an effect of the Indo-Pacific barrier. Differentiation patterns are consistent with a stepping-stone model of dispersal. Genetic differences of Central Pacific populations may reflect founder events associated with colonization of isolated islands, or be a signature of a past bottleneck after population depletion caused by drastic climatic events. 相似文献
90.
Janine W. Y. Wong Bettina Hitzfeld Michael Zimmermann Inge Werner Benoît J. D. Ferrari 《Environmental Sciences Europe》2018,30(1):49