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The present study was conducted to better understand the specific contingency of extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli (E. coli) isolated from urban waters of Wadi Ouislane of the city of Meknes, compared to isolates from patients hospitalized in the resuscitation department at Mohamed V Hospital in Meknes, Morocco. These antibiotic-resistant bacteria have become ubiquitous in effluents, creating increasing concern about their potential impact on human and animal health and the environment. We took four samples of wastewater representative of a day, effluents of the wadi Ouislane. They were analyzed for indicator germs of fecal pollution, namely total coliforms (TC) and fecal coliforms (FC). Bacteria were enumerated by the dilution-filtration technique and by incorporation in solid medium in supercooling. However, four bacteriological samples, taken for clinical purposes from hospitalized patients, were performed at the medical analysis laboratory of Mohamed V Hospital in Meknes. Analysis of our results showed that ESBL-producing E. coli bacteria isolated from our effluents had the same antibiotic resistance profiles as those from hospitalized patients. Urban wastewater discharges into the environment contribute to the dissemination of extended-spectrum beta-lactamase-producing Escherichia coli that may pose health risks to the population.

The aim of this study is to evaluate the ability of the vertical Multi-Soil-Layering filter (V-MSL) to remove indicators of fecal pollution from domestic wastewater under Moroccan conditions. To do this, a V-MSL filter measuring 20 cm deep, 60 cm wide, 78 cm high was installed near the guardian's house of the Razi’s middle school in Meknes to treat domestic wastewater. Three hydraulic loads (250 L/m2/day, 350 L/m2/day and 500 L/m2/day) were tested. This filter showed an average reduction of (97.5 ± 0.3)%, (97.7 ± 0.4)% and (96.0 ± 0.7)%, for total coliforms, fecal coliforms and fecal streptococci, respectively. The performance of the filter was not affected a lot when changing the hydraulic head from 250 L/m2/day to 500 L/m2/day. The bacterial load concentrations at the filter outlet are slightly higher than the WHO recommended standard (1000 CFU / 100mL) for reuse of wastewater in irrigation. To remedy this situation, we recommend the adoption of the principle of treatment of excreta at the source by the use of dry toilets and the treatment of gray water only by the V-MSL filter.

In this work, a relatively new class of materials, rare earth (RE) based high entropy oxides (HEO) are discussed in terms of the evolution of the oxygen vacant sites (O v ) content in their structure as the composition changes from binary to HEO using both experimental and computational tools; the composition of HEO under focus is the CeLaPrSmGdO due to the importance of ceria-related (fluorite) materials to catalysis. To unveil key features of quinary HEO structure, ceria-based binary CePrO and CeLaO compositions as well as SiO 2 , the latter as representative nonreducible oxide, were used and compared as supports for Ru (6 wt % loading). The role of the O v in the HEO is highlighted for the ammonia production with particular emphasis on the N 2 dissociation step (N 2(ads) → N ads ) over a HEO; the latter step is considered the rate controlling one in the ammonia production. Density functional theory (DFT) calculations and 18 O 2 transient isotopic experiments were used to probe the energy of formation, the population, and the easiness of formation for the O v at 650 and 800 °C, whereas Synchrotron EXAFS, Raman, EPR, and XPS probed the Ce-O chemical environment at different length scales. In particular, it was found that the particular HEO composition eases the O v formation in bulk, in medium (Raman), and in short (localized) order (EPR); more O v population was found on the surface of the HEO compared to the binary reference oxide (CePrO). Additionally, HEO gives rise to smaller and less sharp faceted Ru particles, yet in stronger interaction with the HEO support and abundance of Ru-O-Ce entities (Raman and XPS). Ammonia production reaction at 400 °C and in the 10-50 bar range was performed over Ru/HEO, Ru/CePrO, Ru/CeLaO, and Ru/SiO 2 catalysts; the Ru/HEO had superior performance at 10 bar compared to the rest of catalysts. The best performing Ru/HEO catalyst was activated under different temperatures (650 vs 800 °C) so to adjust the O v population with the lower temperature maintaining better performance for the catalyst. DFT calculations showed that the HEO active site for N adsorption involves the O v site adjacent to the adsorption event.