Introduction. Zinc is one of the essential micronutrients for living organisms; so, the right performance of several enzymes depends on this element. This micronutrient is a regulator of phytohormones and chlorophyll synthesis, and also, it is an essential element for the carbohydrates’ metabolisms in plants. Considering the relatively high solubility of ZnO-NPs and also the ability of plants to uptake and accumulate these nanoparticles in their biomass, ZnO-NPs can be used as an effective nanofertilizer for plants’ growth. Methods. In the present study, zinc oxide nanoparticles synthesized using chemical method and the effect of ZnO-NPs (as a nanofertilizer) on seeds’ germination, seedlings’ rootlet, seedlings’ plumule, and seedling’s vigour index in two oilseed crops from the Brassicaceae family, including Brassica napus L. and Camelina sativa, were investigated. After treating the seeds with different concentrations of ZnO-NPs (from 0.1 to 1000 ppm) for 6 days, the germination percentage (GP) of each treatment was measured. Results. The results indicated an increase in GP for both plants treated with 10 ppm ZnO-NPs. For B. napus, the maximum GP occurred in treated seeds with 5 ppm ZnO-NPs which showed a 30% increase of GP compared with the control condition. For Camelina, this maximum GP was observed in 0.1 ppm concentration of ZnO-NPs which showed a 15% increase compared with the control condition. After the germination test, germinated seedlings were planted in Hoagland hydroponic solution and treated with ZnO-NPs again for a week. For both species, treatment with ZnO-NPs showed a great effect on rootlet growth, while the effects of these treatments on plumule were negligible. The maximum rootlet length was observed in treated B. napus seedlings with 5 ppm ZnO-NPs which showed a 32% increase in this parameter compared with the control condition. In contrast, the high concentrations of ZnO-NPs showed toxic effects on B. napus seedlings’ rootlets. Results showed a 41% decrease in B. napus seedlings treated with 50 ppm ZnO-NPs compared with control seedlings. Similar results were observed in the treated seedlings of Camelina. For Camelina seedlings treated with 1 ppm ZnO-NPs, 15% increase in rootlets’ length was observed, while treated Camelina seedlings with 50 ppm ZnO-NPs showed a 68% decrease in rootlet length compared with the control condition. The results of this study indicated the potential of using ZnO-NPs as nanofertilizer for B. napus and Camelina in low concentrations (lower than 10 ppm). In addition, these results suggest the toxicity effects of these nanoparticles on both species in concentrations higher than 50 ppm.

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Background: Background: Increasing nitrate concentrations in groundwater resources is considered a common environmental and public health problem worldwide. In this research, an autotrophic up-flow bioreactor with pumice as media was used to study the effects of the sulfur-to-nitrogen (S/N) ratio and empty bed contact time (EBCT) on nitrate removal efficiency and byproducts. Methods: Experiments were carried out in a 3.47 L up-flow, fixed-bed reactor with 3 sampling ports. To evaluate the overall impact of S/N ratio and EBCT on the performance of the bioreactor, several phases with different S/N ratios and EBCTs were applied. Results: At a constant S/N ratio of 3.85 g/g, as EBCT decreased from 24 hours to 2 hours, the nitrate removal efficiency decreased from 98% to 64%. On the other hand, at the desired EBCT of 4 hr, as S/N ratio decreased from 3.85 to 1.51 g/g, nitrate removal efficiency was reduced from 85% to 32%. Changing the EBCT and S/N ratio also affected the effluent nitrite and sulfate concentrations as byproducts. At the S/N ratio of 3.85 g/g and EBCT of 24 hours, effluent nitrite and sulfate concentrations were 0.1 mg NO 2-N/L and 463 mg SO 4 2-/L, respectively. Decreasing the S/N ratio to 1.51 g/g and the EBCT to 4 hours caused drastic changes in effluent nitrite and sulfate concentrations. Conclusion: The results indicated that the autotrophic denitrification with thiosulfate as electron donor and pumice as media was feasible and applicable for nitrate contaminated groundwater.

Breast cancer is one of the most common cancers known, and it is also a significant cause of death in women. If breast cancer is diagnosed in the early stages of the disease and treated appropriately, we can see an increase in life expectancy for more than 90% of patients. Research on molecular biomarkers with enough sensitivity and specificity can be a good solution for rapid diagnosis in the clinical stage. Meanwhile, endogenous retroviral biomarkers can have good functional benefits. Human Endogenous Retroviruses as heterochromatin fragments of the genome usually lack expression, but in several types of human cancers, including breast cancer, HERV-Kenv mRNA is significantly increased. This study used RT-PCR to detect the expression of HERV-K mRNA and tried to introduce screening tools for the early detection of breast cancer. In this case-control study, blood samples of 50 patients with hospitalized breast cancer and 50 healthy individuals were designed to evaluate the expression of HERV-Kenv mRNA using specific primers and were analyzed by RT-PCR. PCR test was optimized as a positive control using Hela cancer cell line (cervical adenocarcinoma), which expresses the HERV-Kenv gene. Studies on both patient and control groups showed that the increase in mRNA expression was positive in 64% of patients with breast cancer and negative in all healthy individuals. The results indicate an increase in the expression of endogenous human retroviruses (HERVs) in breast cancer. Because the amount of HERV-Kenv mRNA in the blood of breast cancer patients increases dramatically, it is predicted that these mobile genetic elements could be used as a diagnostic biomarker. Article info