Treatability of landfill leachate by combined upflow anaerobic sludge blanket reactor and aerated lagoon

Continuous upflow anaerobic sludge blanket reactor performs more favorably at the higher organic loading rate than other anaerobic treatment. The treatment of municipal landfill leachate of Shiraz’s city investigated using continuous flow anaerobic reactor and subsequently aerated lagoon. Landfill leachate has chemical oxygen demand of 45,000–90,000 mg/L and ammonia nitrogen at 1,000–2,500 and heavy metals that can impact biological treatments. Capacity of anaerobic and aerobic reactors is 10 and 20 L that operated at detention time of 2 and 4 days, respectively. Organic loading rate of upflow anaerobic sludge blanket is between 0.5–20 g chemical oxygen demand/L/day. Chemical oxygen demand removal efficiencies are between 57–87, 35–70 and 66–94% in the anaerobic, aerobic and whole system, respectively. As the entry, leachate organic loading rate increased from 1 to 20 g/L/day, the chemical oxygen demand removal efficiency reached a maximum of 71% and 84% in the anaerobic reactor and whole system, respectively, at high organic loading rate. Ammonium removal efficiency was about 54% after the aerobic stage

Study of damages induced by fungicide propiconazole on testicular tissue and process of spermatogenesis and protective effects of selenium in male Sprague Dawley rat

Background & aim: Propiconazole is an herbal fungicide which is used as a tropical and systematic drug for fungal infection and also as an agricultural chemical for protection and preservation of fruits, vegetables and grains. The aim of this study was to assess the efficacy of fungicides propiconazol and possible protective effects of selenium on testes tissue. Methods: The present expremental trail study was conducted on forty rats which were divided into ten groups of four including control , sham (solvent of propiconazole, distilled water), solvent of selenium (normal saline) and seven experimental groups : group 1 received 0.5 mg/kg/day of selenium, groups 2,3,4 received three doses of 10,50,75 mg/kg/day of Propiconazole, and groups 5,6,7 received three doses of 10, 50, 75 mg/kg/day of propiconazole with 0.5 mg/kg/day of selenium toevaluate. The administration was done intrapritoneal for two weeks in an alternatively fashion. After determining the level of LH, FSH, Testosterone, sperm was counted by hemocitometer. Data were analyzed by the SPSS software using ANOVA test. Results: No significant differences was observed in the level of hormones in the experimental groups2-7 compared with the control group, but the number of sertoli cells, spermatogonia , primary spermatocyte , spermatid and sperm decreased significantly in comparison with the control group (p<0.05). Conclusion: The decrease in numbers of counted sperm indicates that propiconazole has disrupted the production process of these cells and selenium was unable to improve that

Seed priming with hormones does not alleviate induced oxidative stress in maize seedlings subjected to salt stress

Seed priming with hormones has been an efficient method for increasing seed vigor as well as seedling growth under stressful conditions. These responses have in the past been attributed to the activation of antioxidant systems in a range of crops. The results described in this work show that hormonal priming with methyl jasmonate, salicylic acid or CEPA (chloroethylphosphonic acid), an ethylene (ET) releaser, does not induce the antioxidant activity of superoxide dismutase, catalase, ascorbate peroxidase or glutathione reductase in maize seedlings subjected to salt stress. The enhanced biomass of maize seedlings under salt stress that was observed only from ET priming indicates that the stress tolerance in maize from ethylene priming is a fundamental process for stress tolerance acquisition, which is explained, however, by other biochemical mechanisms but not by changes in the antioxidant system