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511.
Corrosion and scaling is one of the most important factors influencing drinking water quality that cause health disorders and economic problems. The aim of this study was to evaluate these phenomena in two sources of surface (Makou city) and ground water (Khoy city) in water networks. Corrosion and scaling potential was surveyed by Langelier, Ryzener, aggressiveness, Larson and Puckorius Indices and with measuring water physical, chemical, and microbial parameters. Statistical paired samples t-test displayed significant difference in means value of Langelier, Ryzener, Puckorius indices between cold and warm seasons of the year in Khoy samples and significant difference in means value of Ryzener, Puckorius and aggressiveness indices between cold and warm seasons of the year in Makou samples (p-value <0.001). Heterotrophic plate count water samples investigated in two cold and hot seasons in Khoy were respectively 14 ± 16 cfu ml?1 and 41 ± 26 cfu ml?1 and in the town of Makou were 11 ± 7 cfu ml?1 and 61 ± 29 cfu ml?1, respectively. In terms of health impacts, corrosion in different mains is important, then providing proper measures for balancing water quality before entering to the network and substituting of mains to prevent economic and health problems are necessary.  相似文献   
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The feasibility of using Portland cement and organobentonite to stabilize and solidify Polycyclic Aromatic Hydrocarbons (PAH) contaminated soil was examined. Naphthalene and phenanthrene in solid and dissolved phases were selected as PAHs compounds to represent organic contaminants in the soil. Different tests including Toxicity Characteristics Leaching Procedure (TCLP), Unconfined Compressive Strength (UCS), and permeability tests were conducted on the stabilization/solidification (S/S) contaminated soils. The leaching test results confirmed a significant reduction in the leaching of naphthalene and phenanthrene from the stabilized soil specimen by adding 2%, 5%, and 10% of organoclay during solidification/stabilization. Based on the results for the tested ranges of cement and organoclay for S/S contaminated soil, the optimum mix design includes 5% of cement and 2% of organoclay. The observation in this study confirmed that organoclay particles sorbed the organic contaminates and therefore naphthalene and phenanthrene leachate concentration will be reduced. Moreover, results show that increasing the curing time of S/S products reduces the naphthalene and phenanthrene leachate concentration.  相似文献   
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Background:Autoimmunity causes the loss of normal immune homeostasis and involves the presence of autoantibodies and inflammation. Thromboangiitis obliterans or Buerger''s disease (BD) refers to a type of vascular obstructive syndrome, with tobacco exposure accounting for disease formation and progression. However, the current understanding of autoimmunity is unclear in the context of BD, and the scientific findings are not enough to support autoimmune mechanisms. This study was aimed at investigating autoimmunity factors in patients with BD.Methods:Clinical and experimental examinations were performed on 80 patients with BD. The diagnostic work-up for autoimmunity was composed of IgM rheumatoid factor (RF), anti-nuclear antibodies (ANA), The erythrocyte sedimentation rate (ESR), anti-cyclic citrullinated peptide (CCP) antibodies, Antiphospholipid antibodies (APA), Anti-cardiolipin antibodies (ACLA), anti-double-stranded DNA (ds-DNA), and extractable nuclear antigen (ENA) profile. Immunomarkers were detected using the quantitative enzyme-linked immunosorbent assay (ELISA).Results:Raynaud''s phenomenon (84.93%), cold sensitivity (76.25%), and claudication (73.75%) were the most common symptoms in the BD patients. Also, 64.29% represented with high ANA levels and positive RF, while 42.11% were found with increased ANA and ESR levels. The ANA/RF positive BD patients had ESR> 15 mm/hr and a high prevalence of cold sensitivity, claudication, and Raynaud''s phenomenon (p> 0.05).Conclusion:There is a possibility of a non-specific autoimmune disposition among BD patients. RF and ANA could be considered for predicting disease progression.Key Words: Antibodies, Autoimmunity, Buerger''s Disease, Immune System  相似文献   
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Molecular Biology Reports - This study is to investigate the binding ability of Designed Ankyrin Repeat Proteins type Ec1that was fused to Low Molecular Weight Protamine (DARPin Ec1-LMWP) protein...  相似文献   
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Plasmonics - Alzheimer’s disease (AD) is a disease in cognitive regions in the human brain. Also the detection of AD in the early stage is too important. In this regard, a surface plasmon...  相似文献   
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Nanotechnology has quite a lot of applications in various fields of industrial sectors like food and agriculture. Although nanotechnology can improve the quality of life, its possible associated risks should be assessed. Here copper oxide nanoparticles (CuO NPs) were synthesized by chemical (polymer pyrolysis) and biological (green) methods with an average size of 30 and 44 nm, respectively. Afterwards, a cell biology approach was applied to evaluate the toxic effects of chemically and biologically synthesized CuO nanoparticles on tobacco cell suspension cultures. Both types of CuO nanoparticles significantly dropped the viability of the cells in a dose and time dependent manner. Accordingly, tobacco cells were found to increase the activity of antioxidant enzymes after 48 h of exposure to nanoparticles. The production of reactive oxygen species (ROS) and malondialdehyde (MDA) in a dose dependent manner was also observed. Assessment of the toxicity of CuO NPs revealed that chemically synthesized NPs were more toxic than biologically synthesized ones. It can be concluded that the organic components of the plant extract as capping agents that remain on the surface of green synthesized CuO NPs may reduce their toxicity effects.  相似文献   
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Bacterial contamination is a serious problem in plant tissue culture procedures. An experiment was conducted to evaluate the potential of nano silver (NS) to remove bacterial contaminants of valerian nodal explants. This experiment was conducted as a completely randomized design in a factorial arrangement with four replications and each replicate with ten explants. Treatments involved NS at two stages (before and after surface sterilization along with control) with three rates (25, 50 and 100 mg l−1) at three times of soaking (30, 60 and 180 min). Explants were cultured on MS medium supplemented with 5 mg l−1 Kin and 0.1 mg l−1 NAA. Results showed that using 100 mg l−1 of NS solution after surface sterilization resulted in the highest percentage (89%) of disinfected explants. Nano silver solution did not affect the characters measured. On the basis of the data obtained in this experiment, it was concluded that NS had a good potential for removing of the bacterial contaminants in plant tissue culture procedures. As this is the first report on application of NS in in vitro culture techniques, further investigations on other plant species are needed to clarify the effectiveness of NS for the removal of bacterial contaminants in tissue culture of other crops.  相似文献   
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