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171.
This paper proposes a mixed performance measurement system using a combination of evolutionary game theory and the balanced scorecard (BSC) in environmental supply chain management (ESCM) that measures and evaluates business operations using the four different perspectives of finance, customer, internal business process, and learning and growth. ESCM plays an important role in the supply chain which leads to the reduction, reuse and recycling of resources involved in both upstream and downstream activities. This paper presents guidance for practical managers in evaluating and measuring ESCM by developing a knowledge-based BSC and evolutionary game theory. The primary purpose of this paper is to apply the proposed method in a case study to one of Iran's biggest auto industry supply chain SAIPA Company. The results of this study indicate that the adoption of ESCM, in the absence of regulatory pressures and cost-saving measures is triggered by public pressures and its implementation is limited by organizational factors and strategic myopia.  相似文献   
172.
There is evidence of continued food insecurity and malnutrition in Pakistan despite significant progress made in terms of food production in recent years. According to “Vision 2030” of the Planning Commission of Pakistan, about half of the population in the country suffers from absolute to moderate malnutrition, with the most vulnerable being children, women, and elderly among the lowest income group. The Government of Pakistan has been taking a series of policy initiatives and strategic measures to combat food insecurity issues. These range from increasing production to food imports, implementation of poverty reduction strategies, nutritional improvement programs, as well as provision of social safety nets. The article aims to instill some fresh thinking into the debate regarding the challenges of food security. It underscores the limitations of hitherto policy response, and suggests crucial measures to improve the present grim scenario. Policy makers, planners, practitioners, and academicians in countries with comparable socio-political and economic setup can view this discussion as a case study and may apply the findings in their domain accordingly.  相似文献   
173.
The outcome of association analysis between species can be influenced by the size and shape of sampling quadrats. To eliminate this problem, a new method is proposed for determining an appropriate size for sampling quadrat. This method is based on measurement of the density of the plant species concerned. The use of this method is illustrated for the detection of association between species in a hypothetical community.  相似文献   
174.
Calendula alata plants were tested for their potential to remove stable cesium and lead from solutions in a 15-day period. The plants were grown hydroponically and placed in solutions containing CsCl and Pb(C?H?O?)? at different concentrations (0.6, 2 and 5 mg l?1). When plants were incubated in CsCl solutions 46.84 ± 2.12%, 41.35 ± 1.59%, and 52.06 ± 1.02% cesium was found to be remediated after 15 days. Moreover, more than 99% lead was removed from the Pb(C?H?O?)? solution in all three concentrations after 15 days during the same period. When both CsCl and Pb(C?H?O?)? were supplemented together in the solution, 9.92 ± 1.22%, 45.56 ± 3.52%, and 46.16 ± 1.48% cesium and 95.30 ± 0.72%, 96.64 ± 0.30%, and 99.02 ± 0.04% lead were removed after 15 days. The present study suggests that hydroponically grown C. alata could be used as a potential candidate plant for phytoremediation of cesium and lead from solutions; however, plants were found to be more efficient for the remediation of lead than cesium.  相似文献   
175.
Available water quality indices have some limitations such as incorporating a limited number of water quality variables and providing deterministic outputs. This paper presents a hybrid probabilistic water quality index by utilizing fuzzy inference systems (FIS), Bayesian networks (BNs), and probabilistic neural networks (PNNs). The outputs of two traditional water quality indices, namely the indices proposed by the National Sanitation Foundation and the Canadian Council of Ministers of the Environment, are selected as inputs of the FIS. The FIS is trained based on the opinions of several water quality experts. Then the trained FIS is used in a Monte Carlo analysis to provide the required input-output data for training both the BN and PNN. The trained BN and PNN can be used for probabilistic water quality assessment using water quality monitoring data. The efficiency and applicability of the proposed methodology is evaluated using water quality data obtained from water quality monitoring system of the Jajrood River in Iran.  相似文献   
176.
In the present study, a total of 198 bacteria were isolated, 88 from the tannery effluents and 110 from agricultural soil irrigated with the tannery effluents. Tannery effluents and soils were analyzed for metal concentrations by atomic absorption spectrophotometer. The tannery effluents and soil samples were found to be contaminated with chromium, nickel, zinc, copper, and cadmium. All isolates were tested for their resistance against Cr6?+?, Cr3?+?, Ni2?+?, Zn2?+?, Cu2?+?, Cd2?+?, and Hg2?+?. From the total of 198 isolates, maximum bacterial isolates were found to be resistant to Cr6?+? 178 (89.9%) followed by Cr3?+? 146 (73.7%), Cd2?+? 86 (43.4%), Zn2?+? 83 (41.9%), Ni2?+? 61 (30.8%), and Cu2?+? 51 (25.6%). However, most of the isolates were sensitive to Hg2?+?. Among the isolates from tannery effluents, 97.8% were resistant to Cr6?+? and 64.8% were resistant to Cr3?+?. Most of the soil isolates were resistant against Cr6?+? (83.6%) and Cr3?+? (81.8%). All isolates were categorized into Gram-positive and Gram-negative bacteria. In a total of 114 Gram-positive isolates, 91.2% were resistant to Cr6?+? followed by 73.7% to Cr3?+?, 42.1% to Zn2?+?, 40.4% to Cd2?+?, and 32.5% to Ni2?+?. Among Gram-negative isolates, 88.1% were found showing resistance to Cr6?+?, 75.0% to Cr3?+?, and 47.6% were resistant to Cd2?+?. Majority of these metal-resistant isolates were surprisingly found sensitive to the ten commonly used antibiotics. Out of 198 isolates, 114 were found sensitive to all antibiotics whereas only two isolates were resistant to maximum eight antibiotics at a time. Forty-one and 40 isolates which constitute 20.7% and 20.2% were resistant to methicilin and amoxicillin, respectively.  相似文献   
177.
Drinking water quality assessment in Southern Sindh (Pakistan)   总被引:1,自引:0,他引:1  
The southern Sindh province of Pakistan adjoins the Arabian Sea coast where drinking water quality is deteriorating due to dumping of industrial and urban waste and use of agrochemicals and yet has limited fresh water resources. The study assessed the drinking water quality of canal, shallow pumps, dug wells, and water supply schemes from the administrative districts of Thatta, Badin, and Thar by measuring physical, chemical, and biological (total coliform) quality parameters. All four water bodies (dug wells, shallow pumps canal water, and water supply schemes) exceeded WHO MPL for turbidity (24%, 28%, 96%, 69%), coliform (96%, 77%, 92%, 81%), and electrical conductivity (100%, 99%, 44%, 63%), respectively. However, the turbidity was lower in underground water, i.e., 24% and 28% in dug wells and shallow pumps as compared to open water, i.e., 96% and 69% in canal and water supply schemes, respectively. In dug wells and shallow pumps, limits for TDS, alkalinity, hardness, and sodium exceeded, respectively, by 63% and 33%; 59% and 70%, 40% and 27%, and 78% and 26%. Sodium was major problem in dug wells and shallow pumps of district Thar and considerable percent in shallow pumps of Badin. Iron was major problem in all water bodies of district Badin ranging from 50% to 69% and to some extent in open waters of Thatta. Other parameters as pH, copper, manganese, zinc, and phosphorus were within standard permissible limits of World Health Organization. Some common diseases found in the study area were gastroenteritis, diarrhea and vomiting, kidney, and skin problems.  相似文献   
178.
Pre-harvest sprouting refers to the precocious germination of the grain in the spike prior to harvest as a result of moist weather conditions at harvest time. From the agricultural viewpoint, it is necessary to impose an exogenous dormancy to wheat seeds in order to improve the resistance of seed to pre-harvest sprouting. In this regard, we found that clove bud essential oil is a strong inhibitor for wheat seed germination. The extract obtained from clove bud by supercritical fluid extraction using CO2 as solvent minimized the number of extracts to two compounds, eugenol and eugenyl acetate. Eugenol, as the main constituent of the oil, was responsible for its strong inhibitory activity in wheat seeds. The aqueous solution of clove bud oil was submitted to germination assay at various concentrations from 50 to 400 mg/L. Complete inhibition of seed germination was recorded when the concentration was 400 mg/L. Roots and sprouts have similar sensitivity to inhibitory effect. In an empirical study, the synergistic cooperation of eugenol and eugenyl acetate from clove bud oil in the inhibition of seed germination was found to be a 1:1 ratio. The clove bud essential oil is widely available and will broaden the horizon of applications for natural and safe inhibitors in the fields.  相似文献   
179.
180.
The practice of incorporating certain waste products into highway construction and repair materials (CRMs) has become more popular. These practices have prompted the National Academy of Science, National Cooperative Highway Research Program (NCHRP) to research the possible impacts of these CRMs on the quality of surface and ground waters. State department of transportations (DOTs) are currently experimenting with use of ground tire rubber ( crumb rubber) in bituminous construction and as a crack sealer. Crumb rubber asphalt concrete (CR-AC) leachates contain a mixture of organic and metallic contaminants. Benzothiazole and 2(3H)-benzothiazolone (organic compounds used in tire rubber manufacturing) and the metals mercury and aluminum were leached in potentially harmful concentrations (exceeding toxic concentrations for aquatic toxicity tests). CR-AC leachate exhibited moderate to high toxicity for algae ( Selenastrum capriconutum) and moderate toxicity for water fleas ( Daphnia magna). Benzothiazole was readily removed from CR-AC leachate by the environmental processes of soil sorption, volatilization, and biodegradation. Metals, which do not volatilize or photochemically or biologically degrade, were removed from the leachate by soil sorption. Contaminants from CR-AC leachates are thus degraded or retarded in their transport through nearby soils and ground waters.  相似文献   
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