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31.
The use of molecular tools, principally qPCR, versus traditional culture-based methods for quantifying microbial parameters (e.g., Fecal Indicator Organisms) in bathing waters generates considerable ongoing debate at the science–policy interface. Advances in science have allowed the development and application of molecular biological methods for rapid (~2 h) quantification of microbial pollution in bathing and recreational waters. In contrast, culture-based methods can take between 18 and 96 h for sample processing. Thus, molecular tools offer an opportunity to provide a more meaningful statement of microbial risk to water-users by providing near-real-time information enabling potentially more informed decision-making with regard to water-based activities. However, complementary studies concerning the potential costs and benefits of adopting rapid methods as a regulatory tool are in short supply. We report on findings from an international Working Group that examined the breadth of social impacts, challenges, and research opportunities associated with the application of molecular tools to bathing water regulations.  相似文献   
32.
Abstract

In the United States, emission processing models such as Emissions Modeling System-2001 (EMS-2001), Emissions Preprocessor System-Version 2.5 (EPS2.5), and the Sparse Matrix Operator Kernel Emissions (SMOKE) model are currently being used to generate gridded, hourly, speciated emission inputs for urban and regional-scale photochemical models from aggregated pollutant inventories. In this study, two models, EMS-2001 and SMOKE, were applied with their default internal data sets to process a common inventory database for a high ozone (O3) episode over the eastern United States using the Carbon Bond IV (CB4) chemical speciation mechanism. A comparison of the emissions processed by these systems shows differences in all three of the major processing steps performed by the two models (i.e., in temporal allocation, spatial allocation, and chemical speciation). Results from a simulation with a photochemical model using these two sets of emissions indicate differences on the order of ±20 ppb in the predicted 1-hr daily maximum O3 concentrations. It is therefore critical to develop and implement more common and synchronized temporal, spatial, and speciation cross-reference systems such that the processes within each emissions model converge toward reasonably similar results. This would also help to increase confidence in the validity of photochemical grid model results by reducing one aspect of modeling uncertainty.  相似文献   
33.
The IAPCS model, developed by U.S. EPA’s Air and Energy Engineering Research Laboratory and made available to the public through the National Technical Information Service, can be used by utility companies, architectural and engineering companies, and regulatory agencies at all levels of government to evaluate commercially available technologies for control of SO2, NOx, and particulate matter emissions from coal-fired utility boilers with respect to performance and cost. The model is considered to be a useful tool to compare alternative control strategies to be used by utilities to comply with the requirements of the CAA, and to evaluate the sensitivity of control costs with respect to many of the significant variables affecting costs.

To illustrate the use of the model for site-specific studies, the authors used the model to estimate control costs for SO2 and NOx control at Detroit Edison’s Monroe plant and two hypothetical plants under consideration and at three plants operated by New York State Electric and Gas Corporation. The economic and technical assumptions used to drive the model were those proposed by the utilities if cited, and if not cited, the model default values were used. The economic format and methodologies for costs cited in the Electric Power Research Institute’s Technical Assessment Guide are used in the IAPCS model. Depending on the specific conditions and assumptions for the cases evaluated, SO2 control costs ranged from $417 to $3,159 per ton of SO2 removed, and NOx control costs ranged from $461 to $3,537 per ton of NOx removed or reduced.  相似文献   
34.
Quantitative results from Environmental Management Systems (EMS) at primary schools have rarely been examined in literature. This paper presents the monitoring results of environmental care in 39 primary schools in Northern South Africa. During 2 years, after the EMS was implemented in the curriculum and in the school's management, the progress of environmental performances of the participating schools has been measured, by means of detailed questionnaires, related to four environmental aspects: water, waste, energy and greening. At the beginning of the project, 50% of the schools performed well on water-related environmental actions. Two years later it was 76%. For waste-related activities the improvement was even stronger: from 50% to 100%. The environmental performances of the schools improved also for greening-related actions, from 50% at the start of the project to 64% two years later. Only energy-related activities did not improve significantly with only 24% of all schools performing well at the end of the survey period.In general, the introduction of an EMS succeeded in an improvement of the overall environmental performances of the schools, but cost-intensive activities were less successful than others.  相似文献   
35.
Phytoremediation, the use of plants for in situ contaminant cleanup, is gaining new appreciation as an aesthetically pleasing, sustainable method that naturally makes use of solar power. Hybrid poplars are widely used because they grow rapidly and have high transpiration rates, making them advantageous for hydraulic control of groundwater. However, the tendency for trees and other vegetation to uptake metals may be a disadvantage in some settings due to potential redistribution of metals from groundwater to the ground surface. Therefore, a pilot test in the upper midwestern United States was implemented to evaluate the applicability of poplars to groundwater withdrawal and metals transport. © 2009 Wiley Periodicals, Inc.  相似文献   
36.
The available national annual air pollution emissions are based on mass. Different air pollutants have greatly different toxicities per unit mass, hence the emissions should be rated by effect, not by mass, so that more sensible priorities can be set in control research and regulation. Effect factors are derived from the health effect literature indirectly by using the national ambient air quality standards. The resulting analysis by effects shows transportation to be still the largest source as it is in the mass analysis while hydrocarbons become the largest pollutants by effect compared to carbon monoxide being the largest pollutant by mass.  相似文献   
37.
Environmental Science and Pollution Research - Persistent organic pollutants (POPs) are still globally distributed and can exert different effects on ecosystems. Little is known about the...  相似文献   
38.
Environmental Science and Pollution Research - There has been alarming depletion of manganese (Mn) reserves owing to the ongoing extensive mining operations for catering the massive industrial...  相似文献   
39.
A new mass estimate for the dodo (Raphus cucullatus), based on the lengths of the femur, tibiotarsus and tarsometatarsus, is attempted. The obtained mean mass is 10.2 kg, which is less than previous estimates based on other methods, which ranged from 10.6 to 21.1 kg, and much lower than the 50 lbs reported by a seventeenth-century eyewitness. The new estimated mass, which is similar to that of a large wild turkey, seems more realistic than previous ones and supports the hypothesis that contemporary illustrations of extremely fat dodos were either exaggerations, or based on overfed specimens. Pictures of “fat” dodos may also have been based on individuals exhibiting a display behaviour with puffed out feathers.  相似文献   
40.
Multi-walled carbon nanotube(MWCNT) sheet was fabricated from a drawable MWCNT forest and then deposited on poly(methyl methacrylate) film. The film was further coated with a natural antimicrobial peptide nisin. We studied the effects of nisin coating on the attachment of Bacillus anthracis spores, the germination of attached spores, and the subsequent biofilm formation from attached spores. It was found that the strong adsorptivity and the super hydrophobicity of MWCNTs provided an ideal platform for nisin coating. Nisin coating on MWCNT sheets decreased surface hydrophobicity, reduced spore attachment, and reduced the germination of attached spores by 3.5 fold, and further inhibited the subsequent biofilm formation by 94.6% compared to that on uncoated MWCNT sheet. Nisin also changed the morphology of vegetative cells in the formed biofilm.The results of this study demonstrated that the anti-adhesion and antimicrobial effect of nisin in combination with the physical properties of carbon nanotubes had the potential in producing effective anti-biofilm formation surfaces.  相似文献   
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