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61.
Abstract

Lung injury in rats challenged with paraquat at 20?mg kg?1 body weight was histopathologically evident by inflammation, hemorrhage, and vascular congestion. Increased levels of reactive oxygen species and lipid peroxidation, decreased glutathione content, and lower tissue antioxidant capacity was found. The effects of N-acetylcysteine and cimetidine, a well-known potent inhibitor for organic cation transport, were examined. Lung injury was attenuated by N-acetylcysteine but not by cimetidine. The findings are consistent with the assumption that beneficial effects of N-acetylcysteine administration in paraquat-challenged animals might be linked to its ability for preserving the cellular redox environment and preventing oxidative stress, while cimetidine might even hasten paraquat-induced lung injury. On the other hand, the effects of cimetidine on paraquat-induced lung injury underline the importance of future studies on the role of transporters in this complication.  相似文献   
62.
Prediction of groundwater depth and elevation is important in quantitative water management especially in arid areas. There are several basins in southwest of Iran, in Zagross Mountain, in which the water wells are distributed along a narrow elliptic ring band around the region. To find the most applicable interpolation method, both of the groundwater depth and elevation are predicted by different kriging methods. It is found that the groundwater elevation and depth can be predicted by different methods. Furthermore, it is found that the methods in which the trend is eliminated predicted the groundwater elevation and depth in central part of the region is with less standard error. Furthermore, the methods with no trend elimination, predicted the groundwater depths with less error near the water wells. Dividing the area to hydro-geologically homogeneous sub-areas improved the interpolation precision.  相似文献   
63.
This paper presents an efficient methodology for developing pollutant discharge permit trading in river systems considering the conflict of interests of involving decision-makers and the stakeholders. In this methodology, a trade-off curve between objectives is developed using a powerful and recently developed multi-objective genetic algorithm technique known as the Nondominated Sorting Genetic Algorithm-II (NSGA-II). The best non-dominated solution on the trade-off curve is defined using the Young conflict resolution theory, which considers the utility functions of decision makers and stakeholders of the system. These utility functions are related to the total treatment cost and a fuzzy risk of violating the water quality standards. The fuzzy risk is evaluated using the Monte Carlo analysis. Finally, an optimization model provides the trading discharge permit policies. The practical utility of the proposed methodology in decision-making is illustrated through a realistic example of the Zarjub River in the northern part of Iran.  相似文献   
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65.
This study focused on accumulation of organochlorine compounds (OCs), including dichloro-diphenyl-trichloroethanes (DDTs), hexachlorobenzene (HCB), hexachlorocyclohexanes (HCHs), and polychlorinated biphenyls (PCBs) accumulation in the muscle of four sturgeon (Persian sturgeon, Acipenser persicus; Stellate sturgeon, Acipenser stellatus; Ship sturgeon, Acipenser nudiventris and Beluga sturgeon, Huso huso) from the southern Caspian Sea. The DDT group was prominent in all of the sturgeon muscle tested constituting almost half or more of the total organochlorine content. Contaminant concentration generally followed this order: DDTs>PCBs>HCHs>HCB. The OCs concentrations in Beluga sturgeon (H. huso) were the highest and over four times higher than in the next highest species (A. nudiventris). From an ecotoxicological point of view, the concentrations of OCs in experimental fishes do not reflect a comparatively clean and pollution-free environment; however, results from this study shown that the inflow of organic pollutants into the Caspian Sea has been reduced when compared with prior studies. Levels of measured OCs in sturgeon were relatively low, but the level of some OCs in some of the specimens tested exceeded the guidelines for food; therefore, the maximum allowable daily consumption rate for sturgeon from this watershed may be limited by DDTs and PCBs content for high risk populations.  相似文献   
66.
67.
Water quality management plans are an indispensable strategy for conservation and utilization of water resources in a sustainable manner. One common industrial use of water is aquaculture. The present study is an attempt to use statistical analyses in order to prepare an environmental water quality monitoring program for Haraz River, in Northern Iran. For this purpose, the analysis of a total number of 18 physicochemical parameters was performed at 15 stations during a 1-year sampling period. According to the results of the multivariate statistical methods, the optimal monitoring would be possible by only 3 stations and 12 parameters, including NH3, EC, BOD, TSS, DO, PO4, NO3, TDS, temperature, turbidity, coliform, and discharge. In other words, newly designed network, with a total number of 36 measurements (3 stations × 12 parameters = 36 parameters), could achieve exactly the same performance as the former network, designed based on 234 measurements (13 stations × 18 parameters = 234 parameters). Based on the results of cluster, principal component, and factor analyses, the stations were divided into three groups of high pollution (HP), medium pollution (MP), and low pollution (LP). By clustering the stations, it would be possible to track the water quality of Haraz River, only by one station at each cluster, which facilitates rapid assessment of the water quality in the river basin. Emphasizing on three main axes of monitoring program, including measurement parameters, sampling frequency, and spatial pattern of sampling points, the water quality monitoring program was optimized for the river basin based on natural conditions of the study area, monitoring objectives, and required financial resources (a total annual cost of about US $2625, excluding the overhead costs).  相似文献   
68.
This article presents a critical reflection on the theory and practice of social sustainability in the built environment, identifies areas of agreement and disagreement, explores theoretical and conceptual gaps and challenges, and suggests practical implications for future research and urban policy. It argues that despite revisionist approaches which challenge the tripartite structure of sustainable development, social dimension of sustainability remains an essential valid pillar. Utilising a qualitative meta-analysis methodology for undertaking critical analysis of previous research and publications on the topic, key themes of theory and practice of social sustainability are identified and critically examined. Accordingly, 10 key formative characteristics of social sustainability and their research and policy implications are introduced. The article concludes with institutional observations for policy-makers to achieve greater success in addressing largely underestimated dimensions of social sustainability in urban settings.  相似文献   
69.
This study aimed to analyze the impact of Zayandehrood Dam on desertification using the spatio-temporal dynamics of land use/land cover (LULC) and land surface temperature (LST) in an arid environment in central Iran from 1987 to 2014. The LULC and LST images were calculated from Landsat TM, ETM+, and OLI data, and their accuracies were assessed against reference data using error matrix and linear regression analysis. Results showed that salty and bare lands increased up to 57,302 ha, while agricultural lands declined substantially (28,275.58 ha) in the region. The changes in LULC classes resulted in dramatic variations in LST values. The average temperature showed a 5.03 °C increase, and the minimum temperature increased by 5.66 °C. LST had an increasing trend in bare lands (8.74 °C), poor rangelands (6.8 °C), agricultural lands (9.46 °C), salty lands (9.6 °C), and residential areas (3.18 °C) in this 27-year period. Rainfall and temperature trend analysis revealed that the main cause of these extreme changes in LULC and LST was largely attributed to the drying up of Zayandehrood River due to dam construction and allocating water mainly for industrial sectors. Results indicate that in addition to LULC changes, the spatio-temporal variations of LST can be used as an effective index in desertification assessment and monitoring in arid environments.  相似文献   
70.
Noise is one of the most harmful agents in the workplace. In addition to the adverse effects of noise on the auditory system, as a stressor it may cause increased blood pressure, cardiovascular disease, anxiety, and impaired secretion of hormones. The purpose of this study was to evaluate changes in urinary catecholamines in workers exposed to industrial noise. This is an experimental study of the workers at the smelter section of Sarcheshmeh Copper Industries done on two separate days. During the first day, urine samples from 20 workers who did not use any hearing protection device, were collected during an 8-h work shift and on the second day the same was done but they were asked to use earplugs. Also 20 people were selected as a control group from people who were not exposed to noise at work. Urinary catecholamine levels were measured with ELISA kits. The mean urinary epinephrine and norepinephrine levels in the workers (without earplugs) was respectively 8.69 and 35.56 μg/8h on the first day and on the second day (with earplugs) dropped to 6.45 and 30.95 μg/8h. Noise reduction by earplugs led to almost significant reductions in urinary epinephrine (p?=?0.05) and significant reductions in norepinephrine (p?=?0.02). The results showed that with noise reduction the urinary excretion of stress hormones, especially norepinephrine significantly decreases and workers are probably less prone to stress-related disorders.  相似文献   
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