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871.
This is a systematic review of literature published since 1992, to determine the effectiveness of interventions in preventing workplace violence and to suggest interventions that need further evaluation research. The health care industry is the topic of 54% of the papers, the retail industry is the topic of 11% of the papers, and the remaining papers address the workplace in general or other situations. This finding drives the organization of this review: the first group of papers discussed in this review evaluates interventions to prevent workplace violence in the retail industry – mostly to prevent robbery and violence to retail workers. Singly or in combination, environmental designs in the retail industry, such as increased lighting to improve visibility and a limited cash-handling policy, can make workers safer, but more research is needed to overcome the barriers to implementation of environmental designs, especially in small businesses. The second group of papers in this review is about interventions to prevent violence to health care workers – mostly training and techniques of dealing with combative patients. Training health care workers to better cope with violent patients and to avoid injury is becoming standard practice, but research is needed to identify specific aspects of training and patient management programs that are most effective.  相似文献   
872.
The primary objective of this paper is to describe the impact of national seat belt enforcement mobilizations in terms of changes in public awareness, perceptions, and opinions as they relate to Operation ABC (Always Buckle Up). In order to monitor changes in public awareness and perceptions, a number of national telephone surveys were conducted. Survey results indicated that the following characteristics were associated with lower self-reported seat belt use rates: (a) males; (b) 18-34 age group; (c) persons with lower income; (d) persons with lower education; (e) persons living in rural areas; (f) residents of the Northeast, Midwest, and Great Lakes; (g) residents of states with secondary enforcement laws; and (h) persons less likely to read a newspaper and more likely to listen to the radio. Telephone surveys also suggested that the following groups are more likely to fail to properly secure a child under 12: (a) persons who say they have problems securing a child in seat belt; (b) farm belt residents; (c) Hispanic and Latinos; (d) persons who indicate that they always wear a seat belt but indicate they have not in the past month; (e) persons with older vehicles; (f) lower income respondents; (g) residents of the Deep South; (h) internet non-users; and (i) urban men. These findings provide support for some basic guidelines and suggestions for conducting seat belt enforcement activities.  相似文献   
873.
The United States' approach to incident prevention and response to hazardous chemical facilities has undergone two major transformations in the last 20 years. The first was triggered by the Bhopal tragedy in 1984, which led to major changes within the US chemical industry and a series of Federal laws and regulations intended to prevent major chemical accidents. A more recent transformation is currently underway in the wake of the 9/11 attacks on New York and Washington. It involves the advent of various security-related requirements affecting many of the same facilities covered under the existing accident prevention rules. This paper provides an overview of these transformations and their impacts.  相似文献   
874.
875.
It has been amply demonstrated that there are reasons for improving the collection of fine participates. Some areas of research and development which may prove fruitful in extending fabric filter capabilities have been suggested.  相似文献   
876.
Wang Y  Murphy MB  Lam JC  Jiao L  Wong CC  Yeung LW  Lam PK 《Chemosphere》2011,83(7):891-896
The contamination status of the marine environment in Hong Kong was studied by measuring concentrations of organochlorine (OC) pollutants (i.e., hexachlorobenzene, aldrin, dieldrin, endrin, mirex, total heptachlor, total chlordane, total DDTs, total PCBs, and total toxaphenes) in the eggs of selected waterbird species from different locations around the city: Little Egret (Egretta garzetta) and Chinese Pond Heron (Ardeola bacchus) from Mai Po Village, Great Egret (Ardea alba) and Black-crowned Night Heron (Nycticorax nycticorax) from A Chau, and Chinese Pond Heron (A. bacchus) from Ho Sheung Heung. The mean concentrations of total PCBs and total DDTs ranged from 191-11 100 ng g−1 lipid and 453-49 000 ng g−1 lipid, respectively. Recent exposure of waterbirds to technical chlordane was found in Hong Kong. The risk characterization demonstrated potential risks to birds associated with exposure to DDE, which was found to cause a reduction in survival of young in Hong Kong Ardeids based on the endpoint in the risk assessment.  相似文献   
877.
Semipermeable membrane devices (SPMDs) were employed to sample sediment pore water in static exposure studies under controlled laboratory conditions using (control pond and formulated) sediments fortified with 15 priority pollutant polycyclic aromatic hydrocarbons (PPPAHs). The sediment fortification level of 750 ng/g was selected on the basis of what might be detected in a sediment sample from a contaminated area. The sampling interval consisted of 0, 4, 7, 14, and 28 days for each study. The analytical methodologies, as well as the extraction and sample cleanup procedures used in the isolation, characterization, and quantitation of 15 PPPAHs at different fortification levels in SPMDs, water, and sediment were reported previously (Williamson, M.S. Thesis, University of Missouri-Columbia, USA; Williamson et al., Chemosphere (This issue--PII: S0045-6535(02)00394-6)) and used for this project. Average (mean) extraction recoveries for each PPPAH congener in each matrix are reported and discussed. No procedural blank extracts (controls) were found to contain any PPPAH residues above the method quantitation limit, therefore, no matrix interferences were detected. The focus of this publication is to demonstrate the ability to sequester environmental contaminants, specifically PPPAHs, from sediment pore water using SPMDs and two different types of fortified sediment.  相似文献   
878.
Overflows and leakage from aboveground storage tanks and pipelines carrying crude oil and petroleum products occur frequently. The spilled hydrocarbons pose environmental threats by contaminating the surrounding soil and the underlying ground water. Predicting the fate and transport of these chemicals is required for environmental risk assessment and for remedial measure design. The present paper discusses the formulation and application of the Oil Surface Flow Screening Model (OILSFSM) for predicting the surface flow of oil by taking into account infiltration and evaporation. Surface flow is simulated using a semi-analytical model based on the lubrication theory approximation of viscous flow. Infiltration is simulated using a version of the Green and Ampt infiltration model, which is modified to account for oil properties. Evaporation of volatile compounds is simulated using a compositional model that accounts for the changes in the fraction of each compound in the spilled oil. The coupling between surface flow, infiltration and evaporation is achieved by incorporating the infiltration and evaporation fluxes into the global continuity equation of the spilled oil. The model was verified against numerical models for infiltration and analytical models for surface flow. The verification study demonstrates the applicability of the model.  相似文献   
879.
PM2.5 (particles with aerodynamic diameters less than 2.5 μm) chemical source profiles applicable to speciated emissions inventories and receptor model source apportionment are reported for geological material, motor vehicle exhaust, residential coal (RCC) and wood combustion (RWC), forest fires, geothermal hot springs; and coal-fired power generation units from northwestern Colorado during 1995. Fuels and combustion conditions are similar to those of other communities of the inland western US. Coal-fired power station profiles differed substantially between different units using similar coals, with the major difference being lack of selenium in emissions from the only unit that was equipped with a dry limestone sulfur dioxide (SO2) scrubber. SO2 abundances relative to fine particle mass emissions in power plant emissions were seven to nine times higher than hydrogen sulfide (H2S) abundances from geothermal springs, and one to two orders of magnitude higher than SO2 abundances in RCC emissions, implying that the SO2 abundance is an important marker for primary particle contributions of non-aged coal-fired power station contributions. The sum of organic and elemental carbon ranged from 1% to 10% of fine particle mass in coal-fired power plant emissions, from 5% to 10% in geological material, >50% in forest fire emissions, >60% in RWC emissions, and >95% in RCC and vehicle exhaust emissions. Water-soluble potassium (K+) was most abundant in vegetative burning profiles. K+/K ratios ranged from 0.1 in geological material profiles to 0.9 in vegetative burning emissions, confirming previous observations that soluble potassium is a good marker for vegetative burning.  相似文献   
880.
Large variations exist in the size, abundance and biota of the two principal categories of freshwater ecosystems, lotic (flowing water; e.g., rivers, streams, deltas and estuaries) and lentic (standing water; lakes, ponds and wetlands) found across the circumpolar Arctic. Arctic climate, many components of which exhibit strong variations along latitudinal gradients, directly affects a range of physical, chemical and biological processes in these aquatic systems. Furthermore, arctic climate creates additional indirect ecological effects through the control of terrestrial hydrologic systems and processes, particularly those associated with cryospheric components such as permafrost, freshwater ice and snow accumulation/ablation. The ecological structure and function of arctic freshwater systems are also controlled by external processes and conditions, particularly those in the headwaters of the major arctic rivers and in the adjacent marine environment. The movement of physical, chemical and biotic components through the interlinked lentic and lotic freshwater systems are major determinants of arctic freshwater ecology.  相似文献   
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