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41.
The present study was carried out to investigate the potential ameliorative effects of lycopene against chlorpyrifos (CPF) toxicity in carp. The fish were divided into 7 different experimental groups and received the following treatments: Group 1, control; Group 2, orally administered corn oil; Group 3, oral lycopene (10 mg kg?1 body weight); Group 4, exposure to 0.040 mg L?1 CPF; Group 5, exposure to 0.040 mg L?1 CPF plus oral administration of 10 mg kg?1 lycopene; Group 6, exposure to 0.080 mg L?1 CPF; and Group 7, exposure to 0.040 mg L?1 CPF plus oral administration of 10 mg kg?1 lycopene. Treatment was continued for 14 d and samples of the blood and tissue (liver, kidney, and gill) were collected at the end of the experiment and analysed for their oxidant–antioxidant status, including the malondialdehyde (MDA) levels, and the superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activity. The samples were also measured for changes in the haematological parameters, such as the red blood cell (RBC) and white blood cell (WBC) counts, the haemoglobin concentration (Hb), the haematocrit (Ht) level, and the erythrocyte indices: the mean corpuscular volume (MCV), the mean corpuscular haemoglobin (MCH) and the mean corpuscular haemoglobin concentration (MCHC). The findings of this study demonstrated that CPF had a negative effect on the haematological parameters and the antioxidant enzyme activities of the fish; this toxic effect was neutralised by the administration of lycopene. The present results suggest that lycopene (10 mg kg?1) can be effective in the protection of CPF-induced toxicity in fish.  相似文献   
42.
Single, dual and triple mixtures of totally seven different mixture combinations of the metals Al, Ba and Fe were examined in Lemna minor (L) culture, Daphnia magna (D) culture and in a consortium culture consisting of L. minor and D. magna. In this study: (a) differences in removed metal proportions at the end of 24 and 48?h, (b) differences in removed metal amounts due to cultures, (c) differences in the removed proportions of a metal in distinct mediums and (d) removal correlation of the metals due to cultures were investigated. The study results showed that among the metals Al, Ba and Fe, Al has the most toxic effect on organisms involved in this study. Although similar toxicity results of Al and Fe on test groups were observed, Ba gave different toxicity results on test groups. An overview of the bioremediation results indicates that L. minor removes the metals Al and Fe more successfully than Ba. Different mixture combinations of metals performed dissimilar removal results in the same cultures. According to the correlations analysis for the metals Ba and Fe, a high correlation was recorded between the consortium group and test groups containing only D. magna, r?=?0.88, r?=?0.91, respectively.  相似文献   
43.
The objective of this research is to evaluate all the critical reaches in a cockpit and determine the visual sufficiency of a cockpit to accommodate 90% of potential pilots. While mismatches of measurements with cockpit dimensions are revealed, proposals are made to improve cockpit ergonomics. Regression models were generated to predict and assure adequate exterior vision. Mean, lower and upper control limits of all measurements were found acceptable except eye level. There are very strong positive relationships between stature and eye level (R2?=?0.972, p?R2?=?0.994, p?SD smaller than the eye level mean or seating adjustment limits in height may be changed. In general, cockpit design is acceptable in terms of fit/reach accommodation for pilots, except eye level and visual variables that could be solved by better seat adjustments.  相似文献   
44.
The aim of this study was to determine the concentrations of nickel and cadmium in blood plasma of the people exposed to cement dust emissions and to investigate the effects of exposure period on the activities of Na+/K+ ATPase enzymes in their erythrocyte membranes. The study was carried out on people living in Eskiehir Çukurhisar rural area, located near a cement factory. Blood samples of the individuals residing in this area were taken from 80subjects (30 for control) following a physical examination. The analysis of plasma samples showed that nickel concentrations in subject group were found to be significantly higher than those of the control group (p < 0.001). Cadmium concentrations were found to be within the reference values for both group and no difference was found between the subjects and controls (p > 0.05). Furthermore, no correlation was observed between the levels of Na+/K+ ATPase activity in erythrocyte membranes of the subject group and the ages of people living in the region (p > 0.05, r = 0.133). It was also observed that nickel concentrations increased by age (p < 0.001, r = 0.646) while no effect was observed in means of cadmium. Na+/K+ ATPase activities in the erythrocyte membranes were not affected.In conclusion although there was no difference between the Na+/K+ ATPase activity in means of age, there was an environmental pollution and may be it was due to the industrial plant.  相似文献   
45.
In order to determine the incidence of confined placental mosaicism (CPM) in term placentae and to show the presence of specific sites and the effect on fetal development, 125 placentae from uneventful pregnancies were analysed by cytogenetic methods. The incidence was at least 4.8 per cent and there were no specific sites on the placenta. Although the number of cases is still too small, we found CPM to be associated with intrauterine growth retardation in six cases.  相似文献   
46.
Local residents’ active participation is essential in protected areas to ensure achievement of conservation goals. One of the important steps for ensuring the active participation of local residents is to determine the perceptions and the factors that influence the perceptions of the local residents toward the protected area. In this context, the researchers of this study try to come up with the perception formed among the local residents toward the protected areas and especially toward Kure Mountains National Park (KMNP), the factors that would influence their perceptions and the ways how their perceptions are influenced. Multivariate linear regression was used to examine the putative influence of variables on perceptions toward protected areas. According to study results, the survey respondents have displayed a positive perception toward the protected areas in the world and in KMNP. It was determined that the respondents formed a positive perception from their economic, environmental and recreational interaction with KMNP. Also, the outcomes of this study showed that the perception developed by local residents toward the protected areas in the world and KMNP are influenced by gender, the level of satisfaction derived from the national park, duration of their residence in the national park, and that the perception that KMNP conservation are beneficial for the source values of the area, the current protection works in the world, as well as its impacts on their living conditions.  相似文献   
47.
Coastal erosion may be caused by natural causes as well as human factors. Karasu town of the city of Sakarya in Turkey which is a touristic region on the Black Sea coast has been experienced a drastic coastal erosion. In recent years, this erosion reached the threatening dimensions for the structures in the settlement. According to the temporal analyses of Landsat satellite images, the maximum erosion on the coastline was detected 100 m between 1987–2013. The results of the study show that the harbour construct on the Karasu coast has the major impact on this event. The secondary factor is that the amount of the sediment carried by the Sakarya River was decreased in time due to different reasons. To prevent the coastal erosion, a series of offshore breakwaters were planned after the failed application of groins on the coastline. In this study, temporal changes of the coastline are investigated by the Landsat satellite data and land surveys, possible reasons of the erosion are discussed and the solutions are proposed regarding the coastal structures.  相似文献   
48.
Journal of Material Cycles and Waste Management - Industrial wastes are considered a major cause of environmental pollution, and studies on valorizing these wastes and converting them into...  相似文献   
49.
Twenty-one surface sediment samples were collected from Akkaya Dam. Heavy metal concentrations (Mo, Cu, Pb, Zn, Ni, Co, Mn, Fe, Cr, As, V and Cd), grain size, organic carbon and carbonate contents were studied in order to assess the extent of environmental pollution and to discuss the origin of these contaminants in sediments of dam. The sediments in the study area are mostly very fine sands. However, mud was observed in the northeast of the dam. Sediment pollution assessment was carried out using enrichment factor. The calculation of enrichment factors showed that Mo is depleted by 1.0 whereas Cu, Pb, Zn, Ni, Co, Mn, As, V, Cr and Cd are enriched by 3, 5.4, 7, 2.7, 2.2, 3.4, 42.3, 2.1, 1.8 and 7.2, respectively. Relatively high concentrations heavy metals occurred in north (textile industry area) and east (Karasu River) due to enrichment controlled by anthropogenic wastes. The results of correlation analysis show low–medium positive and negative correlations among metals, grain size, carbonate contents and organic carbon and indicate that heavy metals in sediments of the Akkaya Dam have different anthropogenic sources.  相似文献   
50.
The environmental impact assessment of mining sites represents nowadays a large interest topic in Romania. Historical pollution in the Rosia Montana mining area of Romania caused extensive damage to environmental media. This paper has two goals: to investigate the environmental pollution induced by mining activities in the Rosia Montana area and to quantify the environmental impacts and associated risks by means of an integrated approach. Thus, a new method was developed and applied for quantifying the impact of mining activities, taking account of the quality of environmental media in the mining area, and used as case study in the present paper. The associated risks are a function of the environmental impacts and the probability of their occurrence. The results show that the environmental impacts and quantified risks, based on quality indicators to characterize the environmental quality, are of a higher order, and thus measures for pollution remediation and control need to be considered in the investigated area. The conclusion drawn is that an integrated approach for the assessment of environmental impact and associated risks is a valuable and more objective method, and is an important tool that can be applied in the decision-making process for national authorities in the prioritization of emergency action.  相似文献   
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