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1.
The present study evaluates the groundwater quality for drinking and agricultural purposes and determines physicochemical characteristics of groundwater in the Sistan and Baluchistan province in Iran. In order to investigate the water quality, sampling was done in 654 open dug wells, the chemical parameters were analyzed, and water quality index was determined. In this regard, Langelier saturation index (LSI), Ryznar Stability index (RSI), Puckorius scaling index (PSI), Larson–Skold index (LS), and Aggressiveness index (AI) were considered to determine water suitability for industrial purposes. Finally, the analytical results were taken to generate the numerical spatial distribution of the parameters using the geographic information system (GIS) environment. According to the results, water sources were less corrosive based on AI and PSI, low and light corrosion according to RSI, and corrosion according to the Larsson–Sckold index. The results of the drinking water quality index showed that 1.2% shared extraction wells were classified as excellent, 52.1% as good, 39% as poor, 6% as very poor, and 1.7% as unsuitable for drinking purpose classes. In addition, irrigating water quality index illustrated that 19.9% and 80.1% wells were placed in the “excellent” and “Good” classes, respectively. Also, the quality of water in this study was categorized as brackish.  相似文献   
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Attempts were made here to apply a modified analytic hierarchy process (AHP) approach based on refinement assay of dominated alternatives in monitoring the most reliable callus maintenance media (supplemented with l-glutamine and Casamino acid) of Taxus baccata callus cultures in terms of five criteria. Generally, regarding stem-derived calli, 6 out of 18 maintenance media were nominated as non-dominated alternatives, and following AHP ranking test Casamino acid-based media (i.e., A12, A15 and A19) were overall nominated as the premiere. Taking leaf-derived calli into account, only l-glutamine-based media in an ascending order of A8, A4, A6, A5, A9 and A3 were introduced as non-dominated alternatives. Such results connote that l-glutamine-based feeding appears to generate more significant results either for continuous calli growth or taxanes production. In contrast, regarding the second explant, stem, both amino acid supplies had fairly equal worth. Our findings, overall, demonstrate promising applications of the proposed AHP method regarding accurate selection of the best callus maintenance cultures of T. baccata for production of different taxanes including paclitaxel, Baccatin III and 10-deacetylbaccatin III. Similarly, this statistical approach could be also applicable for other crops, for instance, for accurate selection of the best callus cultures/media and consequently production improvement of a given plant secondary metabolite/product.  相似文献   
4.
Homologous recombination (HR) is the major pathway for repairing double strand breaks (DSBs) in eukaryotes and XRCC2 is an essential component of the HR repair machinery. To evaluate the potential role of mutations in gene repair by HR in individuals susceptible to differentiated thyroid carcinoma (DTC) we used high resolution melting (HRM) analysis, a recently introduced method for detecting mutations, to examine the entire XRCC2 coding region in an Iranian population. HRM analysis was used to screen for mutations in three XRCC2 coding regions in 50 patients and 50 controls. There was no variation in the HRM curves obtained from the analysis of exons 1 and 2 in the case and control groups. In exon 3, an Arg(188)His polymorphism (rs3218536) was detected as a new melting curve group (OR: 1.46; 95%CI: 0.432-4.969; p = 0.38) compared with the normal melting curve. We also found a new Ser(150)Arg polymorphism in exon 3 of the control group. These findings suggest that genetic variations in the XRCC2 coding region have no potential effects on susceptibility to DTC. However, further studies with larger populations are required to confirm this conclusion.  相似文献   
5.
Landfills leachates are known to contain recalcitrant and/or non-biodegradable organic substances and biological processes are not efficient in these cases. A promising alternative to complete oxidation of biorecalcitrant leachate is the use of ultrasonic process as pre-treatment to convert initially biorecalcitrant compounds to more readily biodegradable intermediates. The objectives of this study are to investigate the effect of ultrasonic process on biodegradability improvement. After the optimization by factorial design, the ultrasonic were applied in the treatment of raw leachates using a batch wise mode. For this, different scenarios were tested with regard to power intensities of 70 and 110 W, frequencies of 30, 45 and 60 KHz, reaction times of 30, 60, 90 and 120 minutes and pH of 3, 7 and 10. For determining the effects of catalysts on sonication efficiencies, 5 mg/l of TiO(2) and ZnO have been also used. Results showed that when applied as relatively brief pre-treatment systems, the sonocatalysis processes induce several modifications of the matrix, which results in significant enhancement of its biodegradability. For this reason, the integrated chemical-biological systems proposed here represent a suitable solution for the treatment of landfill leachate samples.  相似文献   
6.
The aim of this study is to survey the PM10, PM2.5, and PM1 concentrations in rural and urban areas in Tehran province during cold, warm and dust storm days from December 22, 2016 to June 5, 2017 using Grimm Model aerosol spectrometer. During the study period, daily PM10, PM2.5, and PM1 concentrations ranged from 27.2 to 244.96, 8.4 to 77.9, and 6.5 to 56.8 μg/m3 in urban sites, and 22.8 to 286.4, 6 to 41.1, and 2.1 to 20.2 μg/m3 in rural parts, respectively. Particularly, both daily WHO limits for outdoor PM10 (50.0 μg/m3) and PM2.5 (25.0 μg/m3) exceeded in 95% and 83% of the outdoor measurements in winter and 82% and 58% in total sampled days in urban site, respectively. The 24-h average PM10 and PM2.5 concentrations also exceeded by 59% and 18% in winter and by 36% and 14% of all sampling days in rural site, respectively. During the dust storm, the 24-h average PM10, PM2.5, and PM1 concentrations were, respectively 4.7, 2, and 1.96 times higher than those in urban site and 2, 1.7, and 1.3 times more than those in rural site in all sampled days.  相似文献   
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Three cancerostatic platinum compounds (CPCs) including cisplatin, carboplatin and oxaliplatin are complexes of Pt and classified as probable carcinogenic compounds to humans. This study aimed to perform health risk assessment of platinum cytotoxic drugs for drinking water by developing a sensitive analytical method in the water resource of Qom Province in the central part of Iran. Concentrations of the platinum drugs were determined, including 052 ± 0.2 µg/L for cisplatin, 0.94 ± 0.36 µg/L for carboplatin and 0.27 ± 0.16 µg/L for oxaliplatin in influent samples, and 0.24 ± 0.07 µg/L for cisplatin, 0.28 ± 0.05 µg/L for carboplatin and 0.11 ± 0.01 µg/L for oxaliplatin in effluent samples. The results indicated that in all the well water samples related to the groundwater, the concentration of the platinum-based compounds was lower than the calculated limits of quantification (LOQ); the concentration of cisplatin, carboplatin and oxaliplatin across the samples in the station of drinking water distribution was also below the limits of detection (LOD). The resulting margin of exposure (MOE) is lower than one (MOE < 1) for the three groups including children, pregnant women and lactation women related to cisplatin and carboplatin was determined through exposure to raw and untreated drinking water. Further research is recommended to be conducted in this area, particularly environmental fate of metabolites and transformation products.  相似文献   
8.
An infectious disease that is transmitted from animals to humans and vice-versa is called zoonosis. Bacterial zoonotic diseases can re-emerge after they have been eradicated or controlled and are among the world's major health problems which inflict tremendous burden on healthcare systems. The first step to encounter such illnesses can be early and precise detection of bacterial pathogens to further prevent the following losses due to their infections. Although conventional methods for diagnosing pathogens, including culture-based, polymerase chain reaction-based, and immunological-based techniques, benefit from their advantages, they also have their own drawbacks, for example, taking long time to provide results, and requiring laborious work, expensive materials, and special equipment in certain conditions. Consequently, there is a greater tendency to introduce simple, innovative, quicker, accurate, and low-cost detection methods to effectively characterize the causative agents of infectious diseases. Biosensors, therefore, seem to practically be one of those novel promising diagnostic tools on this aim. These are effective and reliable elements with high sensitivity and specificity, that their usability can even be improved in medical diagnostic systems when empowered by nanoparticles. In the present review, recent advances in the development of several bio and nano biosensors, for rapid detection of zoonotic bacteria, have been discussed in details.  相似文献   
9.
Adipose derived adult stem cells (ASCs) are multipotent cells that are able to differentiate into osteoblasts in presence of certain factors. The histological characteristics of periosteum makes it a specific tissue with a unique capacity to be engineered. Higher flexibility of the greater omentum is useful for reconstructive surgery. These criteria make it suitable for tissue engineering. The present study was designed to evaluate bone tissue engineering with periosteal free graft concurrent with ASCs and pedicle omentum in dog model. Twelve young female indigenous dogs were used in this experiment. In omental group (n = 4), end of omentum was wrapped by periosteum of the radial bone in abdomen of each dog. In omental-autogenously ASCs group (n = 4), 1 ml of ASCs was injected into the wrapped omentum with periosteum while in omental-allogenously ASCs group (n = 4), 1 ml of allogenous ASCs was injected. Lateral view radiographs were taken from the abdominal cavity postoperatively at the 2nd, 4th, 6th and 8th weeks post-surgery. Eight weeks after operation the dogs were re-anesthetized and the wrapped omenum by periosteum in all groups was found and removed for histopathological evaluation. Our results showed that omentum–periosteum, omental-periosteum-autogenous ASCs and omental-periosteum-allogenous ASCs groups demonstrated bone tissue formation in the abdominal cavity in dog model. The radiological, macroscopical and histological findings of the present study by the end of 8 weeks post-surgery indicate bone tissue engineering in all three groups in an equal level. The present study has shown that the wrapped omentum with periosteum concurrent with ASCs (autogenous or allogenous ASCs) lead to a favorable bone tissue formation. We suggested that it may be useful when pedicle graft omentum used concurrent with periosteum in the bone defect reconstruction, and this phenomenon should be studied in future.  相似文献   
10.

Background

Cathepsin B is a lysosomal cysteine protease involved in apoptosis and oocytes which have lower developmental competence show higher expression of Cathepsin B. Furthermore, expression of Cathepsin B show a decreasing trend from oocyte toward blastocyst stage.

Results

Present study assessed the effect of cathepsin B inhibitor, E-64, on developmental competency and cryo-survival of pre-implantation ovine IVF derived embryos. Cathepsin B inhibitor was added during day 3 to 8 of development. One μM E-64 was defined as the optimal concentration required for improving blastocyst rate. This concentration also reduced DNA fragmentation and BAX as apoptotic markers while increasing total cell number per blastocyst and improving anti-apoptotic marker, the BCL2. We further showed that addition of 1.0 μM of E-64 during day 3 to 8 of development improved re-expansion and hatching rates of blastocysts post vitrification. E-64 also reduced rate of DNA fragmentation and BAX expression and increased total cell number per blastocyst and BCL2 expression post vitrification. However, addition of E-64 post vitrification reduced the hatching rate.

Conclusion

Therefore, it can be concluded that inhibition of cathepsin B in IVC, not only improves quality and quantity of blastocysts but also improves the cryo-survival of in vitro derived blastocysts.
  相似文献   
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