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991.
This ecological study aimed, through the analysis of 1,146 wards in the South West of England (1998–2002), firstly, to examine whether chemical incidents and public casualties are more likely near complex industry (emissions to land, air or water: Integrated Pollution Control industry, IPC) or industry with emissions to air only (Local Air Pollution Control industry, LAPC). Secondly, the study examined whether industry, incidents and casualties are found close to deprivation. Social inequalities were examined across quintiles of wards. Fifty-two wards (4.5%) contained an IPC industry and 712 (62.1%) an LAPC. Incidents occurred in 132 wards (11.5%), with casualties in 59 (5.1%). Chemical incidents occurred more frequently in wards with LAPC (152, IPC 20); the same was true of casualties (211, 12). With each additional LAPC site in a ward, the risk of an incident rose by 22% (95% confidence interval [CI] 8–38%), suggesting a dose–response relationship. No clear social inequalities were found. In the South West of England, the public are more likely to be affected by an incident occurring at a simple LAPC site rather than a complex IPC site. This has implications for emergency planning which, at present, focusses most attention on the larger, more complex IPC sites.  相似文献   
992.
Recent advances in technologies have lead to a vast influx of data on movements, based on discrete recorded position of animals or fishing boats, opening new horizons for future analyses. However, most of the potential interest of tracking data depends on the ability to develop suitable modelling strategies to analyze trajectories from discrete recorded positions. A serious modelling challenge is to infer the evolution of the true position and the associated spatio-temporal distribution of behavioural states using discrete, error-prone and incomplete observations. In this paper, a Bayesian Hierarchical Model (HBM) using Hidden Markov Process (HMP) is proposed as a template for analyzing fishing boats trajectories based on data available from satellite-based vessel monitoring systems (VMS). The analysis seeks to enhance the definition of the fishing pressure exerted on fish stocks, by discriminating between the different behavioural states of a fishing trip, and also by quantifying the relative importance of each of these states during a fishing trip. The HBM approach is tested to analyse the behaviour of pelagic trawlers in the Bay of Biscay. A hidden Markov chain with a regular discrete time step is used to model transitions between successive behavioural states (e.g., fishing, steaming, stopping (at Port or at sea)) of each vessel. The parameters of the movement process (speed and turning angles) are defined conditionally upon the behavioural states. Bayesian methods are used to integrate the available data (typically VMS position recorded at discrete time) and to draw inferences on any unknown parameters of the model. The model is first tested on simulated data with different parameters structures. Results provide insights on the potential of HBM with HMP to analyze VMS data. They show that if VMS positions are recorded synchronously with the instants at which the process switch from one behavioural state to another, the estimation method provides unbiased and precise inferences on behavioural states and on associated movement parameters. However, if the observations are not gathered with a sufficiently high frequency, the performance of the estimation method could be drastically impacted when the discrete observations are not synchronous with the switching instants. The model is then applied to real pathways to estimate variables of interest such as the number of operations per trip, time and distance spent fishing or travelling.  相似文献   
993.
Paul Foley 《环境政策》2017,26(5):915-937
To contribute to the literature on transnational sustainability governance hybrids, a new fisheries certification program in Iceland that was originally developed as an alternative to the non-governmental Marine Stewardship Council is examined. While this new program appears on the surface to constitute a purely nationalistic reaction against external non-state authority, the new governance institution is also non-governmental and incorporates international norms and institutions. To explain this new governance hybrid, Robert Cox’s International Political Economy approach to production and power is engaged. This approach theorizes the co-constitution of the social forces of production, state–society complexes and global governance. It is argued that the Icelandic case is not entirely localized or unique; it is part of a broader movement in which social forces of production respond to new market-oriented transnational sustainability governance institutions by developing territorially embedded but transnationally legitimate alternatives.  相似文献   
994.
Which organisations saw their positions on two contentious issues reflected in the Irish climate law of 2015, and what role did advocacy coalitions play in the policy process? These questions are answered drawing theoretically from the Advocacy Coalition Framework (ACF) and by conducting a network analysis of survey data collected from the organisations involved in the national climate policy process. The study finds that several institutionally important or economically powerful organisations, particularly those involved in the agricultural sector, as well as the government parties saw their preferences reflected in the law. This resulted in legislation that excluded binding emission reductions targets, differentiating it from similar laws introduced in other European countries. Organisations in favour of stronger regulation formed a coalition to advocate for their positions, but they largely failed to get their way.  相似文献   
995.
996.
The scientific and policy worlds have different goals, which can lead to different standards for what constitutes "proof" of a change or phenomena, and different approaches for characterizing and conveying uncertainty and risk. These differences can compromise effective communication among scientists, policymakers, and the public, and constrain the types of socially compelling questions scientists are willing to address. In this paper, we review a set of approaches for dealing with uncertainty, and illustrate some of the errors that arise when science and policy fail to coordinate correctly. We offer a set of recommendations, including restructuring of science curricula and establishment of science-policy forums populated by leaders in both arenas, and specifically constituted to address problems of uncertainty.  相似文献   
997.
Hydrocarbon vapors associated with spilled petroleum products arouse regulatory concern and can pose a significant health and safety risk. While petroleum products do not contain a significant amount of methane (CH 4 ), high CH 4 contents in soil gas near petroleum spills have been reported. While CH 4 is nontoxic, its accumulation in shallow soil gas represents a potential explosion and asphyxiation hazard, especially in confined spaces. Identifying the source and origin of shallow CH 4 accumulations is an important part of evaluating potential exposure pathways, selecting appropriate remedial measures, and determining environmental liability. This paper discusses the potential nature and anthropogenic sources for shallow CH 4 and how integration of geological, geochemical, and land use data can be used to determine its origin and identify its source. Two case studies are presented, one where CH 4 associated with a gasoline spill is shown to be derived from a natural source rather than the gasoline, and a second where CH 4 associated with spilled crude oil is shown to be produced in the vadose zone by biodegradation of the oil.  相似文献   
998.
The absorption of hydrogen sulfide and methyl mercaptan by aqueous solutions of chlorine, sodium hydroxide, and chlorine plus sodium hydroxide was studied using a two-inch diameter absorption column packed with ¼ inch Intalox saddles. Absorption rates were noticeably affected by chemical reactions occurring in the aqueous chlorine and hydroxide media. These solutions were studied as a means of controlling sulfur-containing gas emissions from kraft paper mills. The absorption studies indicated that aqueous chlorine solutions at a pH above 12 were effective absorbents for hydrogen sulfide removal in absorption equipment designed to tolerate sulfur in suspension. The absorption of methyl mercaptan in aqueous chlorine solutions appeared to be impractical since dimethyl disulfide was apparently the only product formed and was stripped from the tower by the gas stream. Sodium hydroxide solution was an effective absorbent for both methyl mercaptan and hydrogen sulfide when hydroxide to sulfide or mercaptan feed ratios were greater than 1 or 1.8, respectively. The mercaptan absorption coefficient was approximately twice that for sulfide absorption.  相似文献   
999.
This paper presents a detailed review and critical evaluation of current technologies as applied to fine particulate emissions from coal-fired utility boilers. Quantitative assessments of the capabilities of both conventional and novel air pollution control devices to meet three different performance standards—the present New Source Performance Standard (NSPS) of 0.03 Ib particulate/MBtu heat input, and standards of 0.05 and 0.1 Ib particulate/MBtu are included. Each of the three conventional devices (electrostatic precipitator, fabric filter baghouse, and wet scrubber) is compared and rated with respect to eight different performance categories. This information can be used to determine the relative effectiveness and attractiveness of these three control devices. Novel devices are compared and rated in the same manner, the conclusions from which may provide the research administrator with a guide for the selection of those novel devices which offer the best potential for commercialization.

The major conclusions of the investigation are: (1) The use of conventional scrubbers for fine particulate control on coal-fired utility boilers may no longer be feasible at the new NSPS of 0.03 Ib/MBtu. (2) At the old NSPS (0.1 Ib/MBtu) conventional electrostatic precipitators and baghouses were often competitive. For the new stricter standard, however, the baghouse generally is the more attractive alternative. (3) Novel devices appear to offer almost no hope for this particular application (at a commercial level) between now and 1985 and only little hope before 1990.  相似文献   
1000.
This study investigated the lethal and sublethal effects of the pyrethroid insecticide bifenthrin on adult and larval grass shrimp, Palaemonetes pugio, and adult sheepshead minnows, Cyprinodon variegatus. The effects were determined by conducting 96-h aqueous static renewal tests and 24-h static tests with sediment. Oxidative stress biomarkers, lipid peroxidation, glutathione, and catalase were also assessed. The 96-h aqueous LC50 value for adult shrimp was 0.020 μ g/L (95% CI: 0.015–0.025 μ g/L) and for larval shrimp was 0.013 μ g/L (95% CI: 0.011–0.016 μ g/L). The 96-h aqueous LC50 for adult sheepshead minnow was 19.806 μ g/L (95% CI: 11.886–47.250 μ g/L). The 24-h sediment LC50 for adult shrimp was 0.339 μ g/L (95% CI: 0.291–0.381 μ g/L) and for larval shrimp was 0.210 μ g/L (95% CI: 0.096–0.393 μ g/L). The oxidative stress assays showed some increasing trends toward physiological stress with increased bifenthrin concentrations but they were largely inconclusive. Given the sensitivity of grass shrimp to this compound in laboratory bioassays, additional work will be needed to determine if these exposure levels are environmentally relevant.  相似文献   
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