For some persistent pollutants, such as recalcitrant pesticides, the polluted water (urban, agricultural and/or industrial) treated by conventional wastewater treatment plants is in some cases insufficient to achieve the legally required level of purity. This issue is of particular concern in areas where low rainfall does not provide sufficient water resources to meet the needs of agriculture, requiring increased reuse of water from wastewater treatment plants. In this context, Advanced Oxidation Processes (AOPs) hold great promise for the removal of organic pollutants. This study first evaluates the effectiveness of UV/S2O8= compared to heterogeneous photocatalysis using UV/TiO2 processes on the degradation of two commonly used herbicides (terbutylazine and isoproturon) in aqueous solutions using a photoreactor. In addition. the effect of UV wavelength on the degradation efficiency of both herbicides was investigated. Although degradation rate was higher under UV-254/S2O8= nm than under UV-365/S2O8= nm, complete degradation of the herbicides (0.2 mg L-1) was achieved within 30 min under UV-366 nm using a Na2S2O8 dosage of 250 mg L-1 in the absence of inorganic anions. To assess the impact of water matrix, the individual and combined effects of sulphate, bicarbonate and chloride were evaluated. They can react with hydroxyl and sulphate radicals formed during AOPs to form new radicals with a lower redox potential. The results showed negligible effects of sulphate, while the combination of bicarbonate and chloride seemed to be the key for the decrease in herbicide removal efficiency found when working with complex matrices. Finally, the main intermediates detected during the photodegradation process were identified and the likely pathways are proposed and discussed.

Background: The molecular domestication of the gag gene of retrotransposons and retroviruses gave rise to the Gagr gene in the genome of Drosophila. The Gagr protein has a conservative structure in all Drosophila species, suggesting an essential function. As we previously shown, the Gagr gene may play a part in immune response and processes linked to stress reactions. Methods: Tub-GAL4>UAS-Gagr flies, which had the Gagr gene knockdown in all tissues, were compared with the control hybrid Tub-GAL4>w1118. Gagr gene function was verified by RNA-sequencing followed by RT-PCR and physiological tests. Results: In contrast to the control strain, we observed that flies with the Gagr gene knockdown had a shorter lifespan, but the mutant strain was more resistant to heat stress. Also, the Gagr knockdown strain had higher level of transcription of the immune response genes, according to a transcriptome analysis. It has been shown that the ammonium persulfate used to induce stress causes the Toll, Jal-STAT, and Jnk/MAPK signaling pathways to become activated, which results in a systemic response in numerus tissues in the control strain. Conversely, the Gagr gene mutant strain exhibits low expression of the stress response. Enrichment of the molecular function of genes overexpressed under ammonium persulfate stress in the control strain, but not in the Gagr knockdown mutant, revealed a category with 19 transcription factors involved in the control of organism development, morphogenesis and the functioning of the central nervous system. Their expression pattern and the Gagr gene's expression pattern match. The data obtained demonstrates the importance Gagr is to maintaining both the body's immune system and homeostasis.