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111.
Among the most typical consequences of disasters is the near or complete collapse of terrestrial telecommunications infrastructures (especially the distribution network–the 'last mile') and their concomitant unavailability to the rescuers and the higher echelons of mitigation teams. Even when such damage does not take place, the communications overload/congestion resulting from significantly elevated traffic generated by affected residents can be highly disturbing. The paper proposes innovative remedies to the telecommunications difficulties in disaster struck regions. The offered solutions are network-centric operations-cap able, and can be employed in management of disasters of any magnitude (local to national or international). Their implementation provide ground rescue teams (such as law enforcement, firemen, healthcare personnel, civilian authorities) with tactical connectivity among themselves, and, through the Next Generation Network backbone, ensure the essential bidirectional free flow of information and distribution of Actionable Knowledge among ground units, command/control centres, and civilian and military agencies participating in the rescue effort.  相似文献   
112.
Scirpus littoralis is a wetland plant commonly found in Yamuna flood plains of Delhi, India. The ability of Scirpus littoralis to take up and translocate five metals- Mn, Ni, Cu, Zn and Pb from fly ash dosed and metal spiked soils were studied under waterlogged and field conditions for 90 days. Scirpus littoralis accumulated Mn, Ni, Cu, Zn and Pb upto a maximum of 494.92, 56.37, 144.98, 207.95 and 93.08 ppm dry wt., respectively in below ground organs (BO) in 90 days time. The metal content ratios BO/soil (B/S) were higher than shoot/soil ratios (T/S) for all the metals, the highest being for Ni. Metal ratios BO/water (B/W) were also higher than shoot/water (T/W) ratios but the B/W ratio was maximum for Zn. The changes in nutrient status (N, P) in soil water and plants were also studied at interval of 30 days. The Pearson's correlation between metal uptake and N, P uptake were calculated. All the metals except Ni showed negative correlation with nitrogen but they were all non-significant. However, P uptake showed positive correlations with all the metals and all were significant at 1% confidence limit.  相似文献   
113.
Cyanide is a very toxic chemical that is used to extract gold from its ores. Wastewaters from gold mining companies such as Bogoso Gold Limited (BGL) contain cyanide and other potentially toxic chemicals that have adverse effects on human beings and aquatic organisms. This study was conducted to evaluate the human health risk assessment from exposure to free cyanide via oral and dermal contact of surface/underground water by resident adults within the concession of Bogoso Gold Limited. The chronic non-cancer health risk from exposure to cyanide in River Bogo Upstream is 230 and 43 (by Central Tendency Exposure (CTE) parameters respectively). This means that approximately 230 and 43 resident adults are likely to suffer diseases related to cyanide intoxication via oral and dermal contact respectively. For chronic exposure to River Bogo Downstream by resident adults, the non-cancer health risks are: 0.031 and 0.57 via oral and dermal contact for CTE parameters respectively, which also means that, the non-cancer health risks associated with cyanide intoxication is negligible as the hazard index is less than 1.0 via oral and dermal contacts respectively. The results showed that health risk for acute exposure to cyanide by the resident adults is very high. Hence the residents attribute most of the unexplained deaths in the communities to accidental ingestion and dermal contact of cyanide water.  相似文献   
114.
The Mid-Canada Radar Line (MCRL) was built by the Canadian government during the 1950s and closed in the 1960s. MCRL Site 050 located in close proximity to Fort Albany First Nation was a source of polychlorinated biphenyls (PCBs); thus, this site was remediated in 2001. There has been concern in Fort Albany that the Albany River by MCRL Site 050 is still contaminated. We examined whether the aquatic environment surrounding MCRL Site 050 has returned to background levels four years post-remediation using leeches (Haemopis spp.) as bioindicators. Leech data for 2005 indicates that PCB levels remain higher near Site 050 than at the control site upstream; however, there has been a decrease in difference between Site 050 and the control site for leech body burden between years. Thus, the removal of the terrestrial source of PCB contamination at Site 050 appears to have removed the main source of aquatic PCBs.  相似文献   
115.
The present study was designed with an aim to observe the effect of increasing urbanization and traffic activity on the physiology of a foliose lichen, Phaeophyscia hispidula (Ach.) Essl., collected from 13 different localities, growing in their natural habitat, in Pauri and Srinagar, two cities in the Himalayas. Six parameters i.e., Chl. a, Chl. b, total pigment, chlorophyll degradation, carotenoid and total protein content, proved the most useful to assess air pollution, were measured. Chlorophyll content and protein content are an efficient parameter to measure the air quality of a region. The study indicates that P. hispidula is pollution tolerant (adaptation) and able to withstand local emissions from vehicle exhausts.  相似文献   
116.
In the present study, the magnitude of contamination of vegetables with heavy metals (Pb, Zn, Cd, Cr, Cu and Zn) was determined in a long-term wastewater-irrigated agricultural land. Heavy metal concentrations in vegetables were several folds higher in wastewater-irrigated site compared to clean water-irrigated area. The wastewater-irrigated crops analysed in this study are heavily contaminated with heavy metals. Concentrations of Pb, Zn, Cd and Cr in all the sewage-fed vegetables were beyond the safe limit of FAO/WHO and Indian standard. Contamination is at its highest level in radish and spinach. Daily intake values of Pb, Cd and Ni through consumption of sewage-fed vegetables exceeded the recommended oral dose of metal for both adult and children. The study concludes that wastewater irrigation led to accumulation of heavy metals in vegetables causing potential health risk to consumers.  相似文献   
117.
118.
Land use regression (LUR) models have been used successfully for predicting local variation in traffic pollution, but few studies have explored this method for deriving fine particle exposure surfaces. The primary purpose of this method is to develop a LUR model for predicting fine particle or PM(2.5) mass over the five county metropolitan statistical area (MSA) of Los Angeles. PM(2.5) includes all particles with diameter less than or equal to 2.5 microns. In the Los Angeles MSA, 23 monitors of PM(2.5) were available in the year 2000. This study uses GIS to integrate data regarding land use, transportation and physical geography to derive a PM(2.5) dataset covering Los Angeles. Multiple linear regression was used to create the model for predicting the PM(2.5) surface. Our parsimonious model explained 69% of the variance in PM(2.5) with three predictors: (1) traffic density within 300 m, (2) industrial land area within 5000 m, and (3) government land area within 5000 m of the monitoring site. These results suggest the LUR method can refine exposure models for epidemiologic studies in a North American context.  相似文献   
119.
In order to make the judicious use of thiram fungicide and to exploit the potential of agri-polymers, we have developed the starch- poly(acrylamide) and starch-poly(acrylic acid) based agrichemical delivery system (hydrogels) for its controlled and sustained release. Polymeric networks have been prepared by using N,N'-methylenebisacrylamide (N,N-MBAAm) as crosslinker and ammonium persulfate (APS) as initiator and characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and swelling studies. Release dynamics of thiram fungicide from polymeric matrices has been studied for the evaluation of the diffusion mechanism and diffusion coefficients. It has been established that Non-Fickian diffusion mechanism has occurred for the release of thiram from these polymeric matrices. Furthermore, the initial rate of diffusion of thiram from these polymeric matrices is more as compared to the late stages of diffusion, which is analogous to the trends obtained for the diffusion of water molecules from these polymer matrices.  相似文献   
120.
The stability of coumaphos [O,O-diethyl O-(3-chloro-4-methyl-2-oxo-2H-1-benzopyran-7 yl)phosphorothioatel was studied in model dipping vats under field conditions using 14C-labelled and unlabelled coumaphos, with or without additives. The stability of coumaphos in model vats increased significantly by maintaining a pH of 5 by addition of superphosphate. Copper sulphate amendment did not seem to have any additional effect on stability. Potasan was the major metabolite in addition to chlorferon and 4-methylumbelliferone. Coumaphos concentration was doubled in the sediment of vat treated with copper sulphate as compared to the control vat as a result of emulsion breakdown. Chlorferon was the only metabolite detected in the sediment of the former vat indicating inhibition of the anaerobic degradation.  相似文献   
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