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291.
The Tamil Nadu Cyclone, November 1977: A Comparison of Newspaper Reports   总被引:1,自引:0,他引:1  
James Lewis 《Disasters》1979,3(2):123-125
  相似文献   
292.
This article describes the development, use, and learnings of a comprehensive Responsible Care® program as applied to the management of hazardous substances at various stages during the life cycle of the product. The article offers specific examples for stewardship programs in the biocide industry, and discusses the role of the medical community. © 2001 John Wiley & Sons, Inc.  相似文献   
293.
294.
Soil uranium,basement radon and lung cancer in Illinois,USA   总被引:1,自引:0,他引:1  
Using counties as the sampling unit, a significant association between the chemical form of uranium occurring in soils with basement radon levels was found (Spearman r, 0.266; p > |r|, 0.007). Uranium atoms dispersed throughout the soil matrix are efficient emanators of Rn to soil gas, whereas Rn that is trapped diffuses very slowly from the several U-bearing minerals in Illinois soils and does not contribute significantly to explaining basement Rn. Basement Rn level is correlated with annual incidence of male and female lung cancers. Dispersed U is correlated with annual incidence of lung cancer in females with a Spearman correlation coefficient of 0.162 (p > |r|, 0.104) and males of 0.177 (p > |r|, 0.075).  相似文献   
295.
The results of a discrete choice experiment (DCE) as a part of a survey among the urban riverbank residents on the Red River in Winnipeg, Manitoba, Canada, indicated that the risk of over-dike flooding, set at 2 ft above the 1997 flood water level, was a significant determinant of both voluntary and mandatory evacuation, compared to those set at the 1996 or 1997 levels. Mandatory evacuation was more preferred over voluntary evacuation when the likelihood of flooding was at its most severe, and the opposite relationship was the case when the likelihood was low. The notification time for evacuation, suggested as 1, 2, and 4 days, proved to be an insignificant attribute, whereas the respondents indicated significant preference for full flood compensation over an offer of either 80% or 90% flood relief, irrespective of the alternatives of voluntary or mandatory evacuation.  相似文献   
296.
Effects of Mine Drainage on Breakdown of Aspen Litter in Mountain Streams   总被引:1,自引:0,他引:1  
Rates of aspen litter breakdown were measured at 40 sites in streams of the Rocky Mountains of Colorado, U.S.A. The sites encompassed a range of effects of mine drainage, from pristine (no effects) to highly stressed. The pH, concentrations of dissolved zinc, and deposition rates of metal oxides (the three main stresses from mine drainage) were measured in each stream. Rates of litter breakdown were estimated from changes in mass of aspen leaves in litterbags. The biological communities associated with litter breakdown also were evaluated by measuring the biomass of shredding invertebrates in litterbags and the rate of microbial respiration on litter. Of the stresses from mine drainage, concentration of zinc and deposition rate of metal oxides were most closely related (negatively) to rate of litter breakdown. Biomass of shredding invertebrates was also negatively related to concentration of dissolved zinc and deposition of metal oxides. Microbial respiration was negatively related to deposition rate of metal oxides and positively related to concentration of nutrients. Both shredder biomass and microbial respiration were positively related to litter breakdown rate and, together, accounted for 79% of its variation. Recovery of litter breakdown in streams affected by mine drainage requires remediation that limits both dissolved and deposited metals.  相似文献   
297.
ABSTRACT: Understanding the effects of dams on the inundation regime of natural floodplain communities is critical for effective decision making on dam management or dam removal. To test the implications of hydrologic alteration by dams for floodplain natural communities, we conducted a combined field and modeling study along two reaches in the Connecticut River Rapids Macrosite (CRRM), one of the last remaining flowing water sections of the Upper Connecticut River. We surveyed multiple channel cross sections at both locations and concurrently identified and surveyed the elevations of important natural communities, native species of concern, and nonnative invasive species. Using a hydrologic model, HEC‐RAS, we routed estimated pre‐and post‐impoundment discharges of different design recurrence intervals (two year through 100 year floods) through each reach to establish corresponding reductions in elevation and effective wetted perimeter following post‐dam discharge reductions. By comparing (1) the frequency and duration of flooding of these surfaces before and after impoundment and (2) the total area flooded at different recurrence intervals, our goal was to derive a spatially explicit assessment of hydrologic alteration, directly relevant to natural floodplain communities. Post‐impoundment hydrologic alteration profoundly affected the subsequent inundation regime, and this impact was particularly true of higher floodplain terraces. These riparian communities, which were flooded, on average, every 20 to 100 years pre‐impoundment, were predicted to flood at 100 ? 100 year intervals, essentially isolating them completely from riverine influence. At the pre‐dam five to ten year floodplain elevations, we observed smaller differences in predicted flood frequency but substantial differences in the total area flooded and in the average flood duration. For floodplain forests in the Upper Connecticut River, this alteration by impoundment suggests that even if other stresses facing these communities (human development, invasive exotics) were alleviated, this may not be sufficient to restore intact natural communities. More generally, our approach provides a way to combine site specific variables with long term gage records in assessing the restorative potential of dam removal.  相似文献   
298.
The focus of this study was to compare the behavior of different consortiums of aerobic propane-utilizing microorganisms, with respect to both the lag time for growth after exposure to propane, and their ability to transform three chlorinated aliphatic hydrocarbons (CAHs): chloroform (CF), cis-dichloroethylene (c-DCE) and trichloroethylene (TCE). Thirty-three slurry microcosms, representing seven combinations of aquifer solids and groundwater were constructed for this study. The lag time required for establishing propane-utilizing consortiums ranged between 24 and 29 days in 6 of the 7 combinations. Kinetic tests were performed with respect to propane utilization and CAH transformation. After CAH exposure, the ability of the microorganisms to metabolize propane was significantly reduced. CF and TCE were transformed more slowly than c-DCE, the average values of the initial transformation rates being equal to 0.10 ± 0.04, 0.09 ± 0.05 and 0.98 ± 0.18 mol/(L h),respectively. CF caused the greatest reduction in propane uptake rates, whereas c-DCE exhibited an apparently reversible negative effect on propane uptake rates. The estimates of the Monod half-saturation constants relative to CF, TCE and c-DCE resulted in the 2–3 mol/L range, but were characterized by a high degree of uncertainty.  相似文献   
299.
In our previous work we have isolated fetal cells from maternal blood and used fluorescent in situ hybridization (FISH) for chromosome-specific probes to detect aneuploidy. Current efforts in the Baylor College of Medicine programme are focusing on obtaining consistency in flow-sorting methodology and on determining sensitivity and specificity. To this end, systematic evaluation of five glycophorin A (gly A) antibodies all produced agglutination, leading us to abandon the use of gly A antibodies for positive selection of fetal cells. Conversely, we have found LDS-751 to be useful for nuclear selection. CD45 negative selection can best be accomplished by the use of flasks coated with goat antibodies against mouse antibodies. Positive selection by flow sorting for either CD71+ cells or gamma-globin-positive cells seems to be successful. Using these two approaches, we have recently detected male (fetal) cells in pregnancies in which the fetus was 46, XY in 10 of 18 and in 12 of 14 cases, respectively.  相似文献   
300.
Self-insurance against natural disasters   总被引:1,自引:0,他引:1  
Expenditures on self-insurance to mitigate the effects of natural disasters on the value of private assets are examined in a model where individuals are partially insured against financial loss by a public relief program and where private insurance is unavailable. The model predicts that optimal private expenditures on self-insurance will be excessive or insufficient according to the nature of the technology by which individuals protect their assets. The comparative static effects of variations in the level of public compensation, individual wealth, and attitudes toward risk and the degree of environmental uncertainty on self-insurance expenditures and on the magnitude and frequency of public compensation are also characterized and their implications for remedial government policies are examined.  相似文献   
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