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Environmental Science and Pollution Research - Salinity is a worldwide environmental problem of agricultural lands. Smoke and plant growth-promoting bacteria (PGPR) are individually used to improve...  相似文献   
43.
This study develops methods to obtain maps to determine traffic Hot Spots in Konya, Turkey, by applying linear analysis supported by Geographical Information Systems (GIS).Hot Spot analysis is known method but the study differs from former researches at the point of determining of risky zones, classification and illustration of them on the maps with the different accident parameters. The aim is not to contribute another Hot Spot analysis using a number of statistical methods, but to determine the Highest Potential Hot Spots (HPHS), which are inter-sectional clusters, and to use different parameters, such as number of accidents, number of fatalities and injured, and number of accidents with only financial loss.In addition, apart from classical illustrational techniques, Hot Pieces (HPCS) on roads divided into 1 km segments are shown by their grading according to their numerical values. Hence, thematic illustration distinguishes them from others.Another aspect of this study is that, besides investigation of Hot Spots by means of data of accidents of previous years’, Probable Hot Spots (PRHS) were illustrated and highly potential Hot Spots were determined. These latter are candidates for Hot Spots in the near future. Thus, premature accidents can be anticipated easily.The main intention of this study is to emphasize the importance of using criteria, other than total accident number, to illustrate intersection Hot Spots and to constitute a model of accident severity and variety. It is anticipated that the results obtained from highway accidents data will guide improvement of the route segments.  相似文献   
44.
The present study investigates the concentration of Pb, Cd, Ni, Zn, and Cu in the paddy field soils collected from Tumpat, Kelantan. Soil samples were treated with sequential extraction to distinguish the anthropogenic and lithogenic origin of Pb, Cd, Ni, Zn, and Cu. ELFE and oxidizable-organic fractions were detected as the lowest accumulation of Pb, Cd, Ni, Zn, and Cu. Therefore, all the heavy metals examined were concentrated, particularly in resistant fraction, indicating that those heavy metals occurred and accumulated in an unavailable form. The utilization of agrochemical fertilizers and pesticides might not elevate the levels of heavy metals in the paddy field soils. In comparison, the enrichment factor and geoaccumulation index for Pb, Cd, Ni, Zn, and Cu suggest that these heavy metals have the potential to cause environmental risk, although they present abundance in resistant fraction. Therefore, a complete study should be conducted based on the paddy cycle, which in turn could provide a clear picture of heavy metals distribution in the paddy field soils.  相似文献   
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L-Cysteine has protective efficacy in cases of oxidative tissue injury. Sodium valproate is widely used as an anticonvulsant and an antidepressant in spite of hepatotoxicity as side effect. The aim of this study was to evaluate the protective role of L-cysteine in liver toxicity induced by sodium valproate overdose. Release of the hepatic enzymes, aspartate aminotransferase and alanine aminotransferase, and levels of lipid profiles, as well as the oxidative, enzymatic, and non-enzymatic antioxidant were assessed. Liver damage was judged histologically. L-Cysteine decreased the activity of alanine aminotransferase and aspartate aminotransferase, as well as improved the level of lipid profile, increased the enzymatic antioxidant (catalase, superoxide dismutase, glutathione peroxidase and glutathione reductase), and decreased the lipid peroxidation. L-Cysteine administration inhibited liver injury of sodium valproate.  相似文献   
47.
The purpose of this study was to develop a method for the determination of fluroxypyr (4-amino-3,5-dichloro-6-fluro2-pyridyloxyacetic acid) residue in palm oil namely crude palm oil (CPO) and crude palm kernel oil (CPKO). The method involves the extraction of the herbicide from the oil matrix followed by low temperature precipitation and finally quantification of the residues using the high performance liquid chromatography (HPLC). The extraction efficiency of the method was evaluated by conducting recovery studies. The recovery of fluroxypyr from the fortified CPO samples ranged from 78%-111% with the relative values for the coefficient of variation ranging from 1.4 to 8.6%. Furthermore, the recovery of fluroxypyr from the spiked CPKO samples ranged from 91-107% with the relative values for the coefficient of variation ranging from 0.6 to 4.5%. The minimum detection limit of fluroxypyr in CPO and CPKO was 0.05 microg/g. The method was used to determine fluroxypyr residues from the field-treated samples of CPO and CPKO. When fluroxypyr was used for weed control in oil palm plantations no residue was detected in CPO and CPKO irrespective of the sampling interval and the dosage applied at the recommended or double the manufacturer's recommended dosage.  相似文献   
48.
Multivariate analysis of heavy metals concentrations in river estuary   总被引:1,自引:0,他引:1  
Multivariate statistical techniques such as multivariate analysis of variance (MANOVA) and discriminant analysis (DA) were applied for analyzing the data obtained from two rivers in the Penang State of Malaysia for the concentration of heavy metal ions (As, Cr, Cd, Zn, Cu, Pb, and Hg) using a flame atomic absorption spectrometry (F-AAS) for Cr, Cd, Zn, Cu, Pb, As and cold vapor atomic absorption spectrometry (CV-AAS) for Hg. The two locations of interest with 20 sampling points of each location were Kuala Juru (Juru River) and Bukit Tambun (Jejawi River). MANOVA showed a strong significant difference between the two rivers in terms of heavy metal concentrations in water samples. DA gave the best result to identify the relative contribution for all parameters in discriminating (distinguishing) the two rivers. It provided an important data reduction as it used four parameters (Zn, Pb, Cd and Cr) affording 100% correct assignations. Results indicated that the two rivers were different in terms of heavy metals concentrations in water, and the major difference was due to the contribution of Zn. A negative correlation was found between discriminate functions (DF) and Cr and As, whereas positive correlation was exhibited with other heavy metals. Therefore, DA allowed a reduction in the dimensionality of the data set, delineating a few indicator parameters responsible for large variations in heavy metal concentrations. Correlation matrix between the parameters exhibited a strong evidence of mutual dependence of these metals.  相似文献   
49.
The objective of this study is to investigate the utilization potential of several organic residues in clay bricks. Sawdust, tobacco residues, and grass are widespread by-products of industrial and agricultural processes in Turkey. These residue materials have long cellulose fibres. Sawdust and tobacco residues generally are used as fuel, and the grass is utilized for agricultural purposes. The insulation capacity of brick increases with the increasing porosity of the clay body. Combustible, organic types of pore-forming additives are most frequently used for this purpose. For this reason, increasing amounts of organic residues (0%, 2.5%, 5% and 10% in wt.) were mixed with raw brick-clay. All samples were fired at 900 degrees C. Effects on shaping, plasticity, density, and mechanical properties were investigated. The organic residue additions were found to be effective for pore-forming in the clay body with the clay maintaining acceptable mechanical properties. It was observed that the fibrous nature of the residues did not create extrusion problems. However, higher residue addition required a higher water content to ensure the right plasticity. As a result, sawdust, tobacco residues, and grass can be utilized in an environmentally safe way as organic pore-forming agents in brick-clay.  相似文献   
50.
Nutritional risk factors for older refugees   总被引:1,自引:0,他引:1  
Pieterse S  Ismail S 《Disasters》2003,27(1):16-36
This study describes risk factors for poor nutrition among older Rwandan refugees. The most important areas of nutritional risk for older refugees are: physical ability and mobility; income and access to land; access to appropriate food rations; meeting basic needs such as water, fuel, shelter; equal access to essential services (food distribution, health services, mills, feeding programmes); and psycho-social trauma. Women and older elderly (> 70 years) are significantly more often in disadvantaged positions, such as having poor socio-economic status, poor health, poor mobility, lower food intake, diminished social status, respect and social network. Older refugees are at higher risk than younger refugees and at higher risk than older people in stable situations. They should remain in good nutritional and general health for their own well-being and that of their dependants. In addition to an adequate diet, a support network seems to be an important preventive aspect.  相似文献   
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