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Regional Environmental Change - Replacement of conventional energy sources with renewables such as solar panels and wind turbines requires adequate land. Impact assessments should be conducted to...  相似文献   
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As part of the DAPPLE programme two large scale urban tracer experiments using multiple simultaneous releases of cyclic perfluoroalkanes from fixed location point sources was performed. The receptor concentrations along with relevant meteorological parameters measured are compared with a three screening dispersion models in order to best predict the decay of pollution sources with respect to distance. It is shown here that the simple dispersion models tested here can provide a reasonable upper bound estimate of the maximum concentrations measured with an empirical model derived from field observations and wind tunnel studies providing the best estimate. An indoor receptor was also used to assess indoor concentrations and their pertinence to commonly used evacuation procedures.  相似文献   
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The dynamics of arsenic in four paddy fields in the Bengal delta   总被引:4,自引:0,他引:4  
Irrigation with arsenic contaminated groundwater in the Bengal Delta may lead to As accumulation in the soil and rice grain. The dynamics of As concentration and speciation in paddy fields during dry season (boro) rice cultivation were investigated at 4 sites in Bangladesh and West Bengal, India. Three sites which were irrigated with high As groundwater had elevated As concentrations in the soils, showing a significant gradient from the irrigation inlet across the field. Arsenic concentration and speciation in soil pore water varied temporally and spatially; higher As concentrations were associated with an increasing percentage of arsenite, indicating a reductive mobilization. Concentrations of As in rice grain varied by 2-7 fold within individual fields and were poorly related with the soil As concentration. A field site employing alternating flooded-dry irrigation produced the lowest range of grain As concentration, suggesting a lower soil As availability caused by periodic aerobic conditions.  相似文献   
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Following isopycnic sedimentation in density gradients of colloidal silica (Ludox AM), zooplankton segregated into 3 broad bands of increasing density which included, respectively, fish eggs, invertebrates, and fish larvae. The zone of fish eggs was contaminated with Sagitta spp. and the zone of fish larvae was overlapped partially by mysids and euphausids. We have sought to minimize contamination through modifications of the silica gradients which might shift banding densities of the ichthyoplankton or of the contaminating invertebrates. Density shifts in fact occurred in different commercial formulations of silica sols and in gradients modified by small amounts of polymers, osmotica or charged small molecules. Sagitta were specifically shifted out of the zone of fish eggs by the addition, of 1% w/v dextran sulfate or in a silica sol composed of very small particles of silica (Nalcoag 1115). Fish larvae were shifted to higher densities by the addition of 1% w/v trimetaphosphate or 1% w/v dextran sulfate. Additions of 1% w/v polyvinyl alcohol, and of 10 mM glycine, and potassium phosphate had intermediate effects. The same banding densities of plankton in silica gradients were reached in less than 10 h at one gravity, independent of the immediate pretreatment of the sample.  相似文献   
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A sheep dosed topically with 14C-crufomate (4-tert-butyl-2-chlorophenyl methyl methylphosphoramidate) excreted 45.5% of the 14C dose in the urine within 9 days. The feces contained 1.2% and the carcass 40.4% (this included the 37.7% of the dose remaining on the skin in the dosing area) of the dose. At sacrifice, the fat, liver, kidney, lung, and skin (where the dose was applied) contained the highest concentrations of 14C. Fourteen urinary metabolites were isolated and characterized by mass spectrometry. The metabolic reactions involved were oxidations of the t-butyl moiety, O-demethylation, replacement of the H-N-CH3 moiety with a hydroxyl group, oxidation of the N-methyl group to yield N-formyl phosphoramidates, hydrolysis of the phosphoramidate moiety to yield phenols, conjugation with glucuronic acid and combinations of these reactions.  相似文献   
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The cement industry is one of the largest carbon dioxide (CO2) emitters in the Thai industry. The cement sector accounted for about 20,633 kilotonnes (ktonnes) CO2 emissions in 2005 in Thailand. A bottom-up CO2 abatement cost curve (ACC) is constructed in this study for the Thai cement industry to determine the potentials and costs of CO2 abatement, taking into account the costs and CO2 abatement of different technologies. The period of 2010–2025 is chosen as the scenario period. We analyzed 41 CO2 abatement technologies and measures for the cement industry. Using the bottom-up CO2 ACC model, the cost-effective annual CO2 abatement potential for the Thai cement industry during the 15 year scenario period (2010–2025) is equal to 3095 ktonnes CO2/year. This is about 15% of the Thai cement industry’s total CO2 emissions in 2005. The total technical annual CO2 abatement potential is 3143 ktonnes CO2/year, which is about 15.2% of the Thai cement industry’s total CO2 emissions in 2005. We also conducted a sensitivity analysis for the discount rate parameter.  相似文献   
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Objective: There has been a longstanding desire for a map to convert International Classification of Diseases (ICD) injury codes to Abbreviated Injury Scale (AIS) codes to reflect the severity of those diagnoses. The Association for the Advancement of Automotive Medicine (AAAM) was tasked by European Union representatives to create a categorical map classifying diagnoses codes as serious injury (Abbreviated Injury Scale [AIS] 3+), minor/moderate injury (AIS 1/2), or indeterminate. This study's objective was to map injury-related ICD-9-CM (clinical modification) and ICD-10-CM codes to these severity categories.

Methods: Approximately 19,000 ICD codes were mapped, including injuries from the following categories: amputations, blood vessel injury, burns, crushing injury, dislocations/sprains/strains, foreign body, fractures, internal organ, nerve/spinal cord injury, intracranial, laceration, open wounds, and superficial injury/contusion. Two parallel activities were completed to create the maps: (1) An in-person expert panel and (2) an electronic survey. The panel consisted of expert users of AIS and ICD from North America, the United Kingdom, and Australia. The panel met in person for 5 days, with follow-up virtual meetings to create and revise the maps. Additional qualitative data were documented to resolve potential discrepancies in mapping. The electronic survey was completed by 95 injury coding professionals from North America, Spain, Australia, and New Zealand over 12 weeks. ICD-to-AIS maps were created for: ICD-9-CM and ICD-10-CM. Both maps indicated whether the corresponding AIS 2005/Update 2008 severity score for each ICD code was AIS 3+, 1/2, or indeterminable. Though some ICD codes could be mapped to multiple AIS codes, the maximum severity of all potentially mapped injuries determined the final severity categorization.

Results: The in-person panel consisted of 13 experts, with 11 Certified AIS specialists (CAISS) with a median of 8 years and an average of 15 years of coding experience. Consensus was reached for AIS severity categorization for all injury-related ICD codes. There were 95 survey respondents, with a median of 8 years of injury coding experience. Approximately 15 survey responses were collected per ICD code. Results from the 2 activities were compared, and any discrepancies were resolved using additional qualitative and quantitative data from the in-person panel and survey results, respectively.

Conclusions: Robust maps of ICD-9-CM and ICD-10-CM injury codes to AIS severity categories (3+ versus <3) were successfully created from an in-person panel discussion and electronic survey. These maps provide a link between the common ICD diagnostic lexicons and the AIS severity coding system and are of value to injury researchers, public health scientists, and epidemiologists using large databases without available AIS coding.  相似文献   
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