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31.
Prasenjit Maiti 《国际发展与全球生态学杂志》2013,20(4):289-294
The politics of development includes subtexts of choice, as underpinned by community consensus (or lack of it), against the larger backdrop of a liberal democracy, with its intricate power structures that influence the choice of concepts and often lead to complicity rather than consent. A dilemma exists between the understanding of field-level practitioners and that of academics, whose understandings of progress differ. Progress can (and often does) imply long-term change across generations whereas development is often more a matter of crisis management and delivering tangible results to end-users. This makes it a bone of contention across political systems, irrespective of local or global dynamics. Development can emerge as a tool to be wielded for power and further political mileage at the expense of progress. Progress cannot be studied as a counterpoint to development as the sense of history is often missing in development interventions. Development tends to be piecemeal as its very logic often stems from the rationale of power. This is not to suggest, however, that development is only about politics; it is definitely more than the politics of everyday life and involves all of civil society that requires its critical and immediate attention. In this sense, it has become a priority for politicians with an underlying agenda designed to out-manouevre dissent and all statements of protest. 相似文献
32.
A relative risk model for roof and side fall fatal accidents was developed using loglinear analysis of two-way contingency table. A few statistics such as potential fatalities (PF), relative risk of fatalities (RRF) and safety measure effectiveness (SME) were derived which can be used as key safety performance indicators of roof and side fall accidents in underground mines. The model was applied to large roof and side fall fatal accident data for a period of 6-years occurred in six companies involving 292 underground coal mines. The application reveals that effectiveness of safety measures across different locations in underground mines varies and focus is mainly concentrated in highly populated workplaces such as face. The model and the statistics developed in this study are generic and can be applied to any industrial setting. 相似文献
33.
Speciations of metals were assessed in a tropical rain-fed river, flowing through the highly economically important part of the India. The pattern of distribution of heavy metals (Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn) were evaluated in water and sediment along with mineralogical characterization, changes with different water quality parameters and their respective health hazard to the local population along the Damodar River basin during pre-monsoon and post-monsoon seasons. The outcome of the speciation analysis using MINTEQ indicated that free metal ions, carbonate, chloride and sulfate ions were predominantly in anionic inorganic fractions, while in cationic inorganic fractions metal loads were negligible. Metals loads were higher in sediment phase than in the aqueous phase. The estimated values of Igeo in river sediment during both the seasons showed that most of the metals were found in the Igeo class 0–1 which represents unpolluted to moderately polluted sediment status. The result of partition coefficient indicated the strong retention capability of Cr, Pb, Co and Mn, while Cd, Zn, Cu and Ni have resilient mobility capacity. The mineralogical analysis of sediment samples indicated that in Damodar River, quartz, kaolinite and calcite minerals were dominantly present. The hazard index values of Cd, Co and Cr were >?1 in river water, which suggested potential health risk for the children. A combination of pragmatic, computational and statistical relationship between ionic species and fractions of metals represented a strong persuasion for identifying the alikeness among the different sites of the river. 相似文献
34.
Ajay Kumar Sabyasachi Rout R. K. Singhal P. M. Ravi R. M. Tripathi 《Journal of Coastal Conservation》2016,20(4):289-297
Bio-diffusion mixing rates (Db) were estimated from depth profiles of excess 210Pb and 137Cs in three sediment cores collected from Mumbai Harbour Bay (MHB) using a steady state vertical advection - diffusion model. The mean of 210Pb and 137Cs derived Db values along the studied area were obtained to be about 23 and 36 cm2y?1 respectively. These derived values were within the range of literature values reported for other equivalent environment internationally. The relatively higher Db values for 137Cs profiles demonstrated that particles have diffused more intensely within the surface layer of sediments over 1 year. Conversely, low Db values for 210Pb indicate slow mixing rates in the sediment profile which might be resulted from low 210Pb flux and diffusion of 222Rn to the seafloor. The significant differences between 210Pb and 137Cs derived Db values among cores indicate that there appeared to be as regional differences in sediment properties and local variability in the intensity of seafloor mixing. Furthermore, Db values also depend on differences in characteristic time and depth scales of radionuclides in cores, benthic fauna abundances, organic carbon flux to the sediments and primary production in overlying surface waters. Comparison of 210Pb derived Db values with those calculated from 137Cs distributions reveals better agreement for core 2 than core 1 and 3. The agreement may be fortuitous because 137Cs appears significantly deeper than 210Pb in all cores. It was also observed that Db values increases as sediment accumulation rate increases for both radionuclide. 相似文献
35.
Sangita Maiti Dutta Soumyajit Banerjee Mustafi Sanghamitra Raha Susanta Kumar Chakraborty 《Environmental monitoring and assessment》2014,186(12):8961-8967
Expression of the stress biomarkers 70-kDa heat shock proteins (Hsp70) and manganese superoxide dismutase (MnSOD) was measured as the molecular basis of adaptive response against increased experimental temperatures (32–40 °C for a span of 24–72 h) on the fresh water molluscan species, Bellamya bengalensis (Lamark 1882). The experimental snail specimens were collected during summer and winter seasons from two contrasting wetlands: an ecorestored (free from human interference) site (SI) and other experiencing anthropogenic stresses (SII). The mortality rate of the B. bengalensis and the immunoblotting of MnSOD and Hsp70 of their digestive glands were performed at regular intervals during the period of heat stress. The SI provided a lower stress environment based on physicochemical parameters such as pH, dissolved oxygen (DO), biological oxygen demand (BOD), chemical oxygen demand (COD), and alkalinity for the survival of test species, although both sites experienced mortality due to thermal stresses. The parity in protein expressions displayed a uniform mode of adaptive impact to temperature elevations in both field and laboratory exposure. The Hsp70 expression was minimal at lower thermal stress, but increased with a rise in temperature. It is very likely that higher Hsp70 levels are not directly related to survival or adaptation. In contrast, MnSOD levels appeared to be an indicator of adaptive responses vis-a-vis survival of the animals. So, the expression levels of a universal free radical scavenger like MnSOD are recognized as a potential biomarker in a bioindicator species like Bellamya. 相似文献
36.
Mukesh Singh Avijit Das Debashree Singh Pratiti Maiti Md. Shabbir Anangsha Das 《Environmental Chemistry Letters》2014,12(2):321-327
Water pollution is a major environmental problem worldwide. In particular, shipyards are contaminating waters with iron, lead and copper filings, paints, petrochemical products and solvents. There are only a few reports on the genotoxicity of shipyard contaminants. Here, we study genotoxic effects of surface water from five sites of Hooghly River in West Bengal, India, along the banks of which many shipbuilding and scrap industries are located. Genotoxicity was measured by the detection of micronuclei in Allium cepa and other chromosomal aberrations, as well as damage to genomic DNA of calf thymus. Results show that A. cepa roots treated with contaminated water induced morphological distortions, formation of micronuclei and various types of chromosomal aberrations. The mitotic index was lower than 50 % in the treated samples. The breakage of calf thymus DNA was time-dependent with acute damage of 100 % for overnight incubation as evidenced by agarose gel electrophoresis. We conclude that the workers of local shipbuilding and scrap industries, the residents of nearby areas and the aquatic biodiversity are vulnerable to contaminated waters. 相似文献
37.
Saumen Maiti V. C. Erram Gautam Gupta Ram Krishna Tiwari U. D. Kulkarni R. R. Sangpal 《Environmental monitoring and assessment》2013,185(4):3445-3465
Deplorable quality of groundwater arising from saltwater intrusion, natural leaching and anthropogenic activities is one of the major concerns for the society. Assessment of groundwater quality is, therefore, a primary objective of scientific research. Here, we propose an artificial neural network-based method set in a Bayesian neural network (BNN) framework and employ it to assess groundwater quality. The approach is based on analyzing 36 water samples and inverting up to 85 Schlumberger vertical electrical sounding data. We constructed a priori model by suitably parameterizing geochemical and geophysical data collected from the western part of India. The posterior model (post-inversion) was estimated using the BNN learning procedure and global hybrid Monte Carlo/Markov Chain Monte Carlo optimization scheme. By suitable parameterization of geochemical and geophysical parameters, we simulated 1,500 training samples, out of which 50 % samples were used for training and remaining 50 % were used for validation and testing. We show that the trained model is able to classify validation and test samples with 85 % and 80 % accuracy respectively. Based on cross-correlation analysis and Gibb’s diagram of geochemical attributes, the groundwater qualities of the study area were classified into following three categories: “Very good”, “Good”, and “Unsuitable”. The BNN model-based results suggest that groundwater quality falls mostly in the range of “Good” to “Very good” except for some places near the Arabian Sea. The new modeling results powered by uncertainty and statistical analyses would provide useful constrain, which could be utilized in monitoring and assessment of the groundwater quality. 相似文献
38.
Comparison between availability of heavy metals in dry and wetland tailing of an abandoned copper tailing pond 总被引:2,自引:0,他引:2
Wetland sediments are generally considered as a sink for metals and, in the anoxic zone, may contain very high concentrations
of heavy metals in reduced state. A comprehensive study was carried out to compare the differences of total, environmentally
available (Env-Av), HOAC, EDTA and DTPA available heavy metal fraction in tailing of the marshy area of a copper tailing pond
and the dry tailing. The average concentrations of all the seven metals in the wetland tailing were found higher than dry
tailing. Regarding pH, organic carbon, availailable N, P and K also found higher in marshy wetland tailing compare to the
dry tailing. This information is needed in order to understand wetland system and to assure that wetlands do not themselves
eventually become sources of metal contamination to surrounding areas. But as levels of pollutants increases, the ability
of a wetland system to incorporate waste can be impaired and the wetland can become a source of toxicity. 相似文献
39.
Maintenance policy selection is a multiple criteria decision making. The criteria often considered are cost and reliability of maintenance. There has been a growing interest in using risk of accidents as a criterion for maintenance selection. This paper presents an approach of maintenance selection based on risk of equipment failure and cost of maintenance. Analytic hierarchy process (AHP) and goal programming (GP) are used for maintenance policy selection. A case study in a benzene extraction unit of a chemical plant was done. The AHP results show that considering risk as a criterion, condition based maintenance (CBM) is a preferred policy over time-based maintenance (TBM) as CBM has better risk reduction capability than TBM. Similarly, considering cost as a criterion, corrective maintenance (CM) is preferred. However, considering both risk and cost as multiple criteria, the AHP–GP results show that CBM is a preferred approach for high-risk equipment and CM for low risk equipment. 相似文献