Antibiotic resistance is a global health crisis that requires urgent action to stop its spread. To counteract the spread of antibiotic resistance, we must improve our understanding of the origin and spread of resistant bacteria in both community and healthcare settings. Unfortunately, little attention is being given to contain the spread of antibiotic resistance in community settings (i.e., locations outside of a hospital inpatient, acute care setting, or a hospital clinic setting), despite some studies have consistently reported a high prevalence of antibiotic resistance in the community settings. This study aimed to investigate the prevalence of antibiotic resistance in commensal Escherichia coli isolates from healthy humans in community settings in LMICs. Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we synthesized studies conducted from 1989 to May 2020. A total of 9363 articles were obtained from the search and prevalence data were extracted from 33 articles and pooled together. This gave a pooled prevalence of antibiotic resistance (top ten antibiotics commonly prescribed in LMICs) in commensal E. coli isolates from human sources in community settings in LMICs of: ampicillin (72% of 13,531 isolates, 95% CI: 65–79), cefotaxime (27% of 6700 isolates, 95% CI: 12–44), chloramphenicol (45% of 7012 isolates, 95% CI: 35–53), ciprofloxacin (17% of 10,618 isolates, 95% CI: 11–25), co-trimoxazole (63% of 10,561 isolates, 95% CI: 52–73), nalidixic acid (30% of 9819 isolates, 95% CI: 21–40), oxytetracycline (78% of 1451 isolates, 95% CI: 65–88), streptomycin (58% of 3831 isolates, 95% CI: 44–72), tetracycline (67% of 11,847 isolates, 95% CI: 59–74), and trimethoprim (67% of 3265 isolates, 95% CI: 59–75). Here, we provided an appraisal of the evidence of the high prevalence of antibiotic resistance by commensal E. coli in community settings in LMICs. Our findings will have important ramifications for public health policy design to contain the spread of antibiotic resistance in community settings. Indeed, commensal E. coli is the main reservoir for spreading antibiotic resistance to other pathogenic enteric bacteria via mobile genetic elements.

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Over 80% of wastewater worldwide is released into the environment without proper treatment. Whilst environmental pollution continues to intensify due to the increase in the number of polluting industries, conventional techniques employed to clean the environment are poorly effective and are expensive. MXenes are a new class of 2D materials that have received a lot of attention for an extensive range of applications due to their tuneable interlayer spacing and tailorable surface chemistry. Several MXene‐based nanomaterials with remarkable properties have been proposed, synthesized, and used in environmental remediation applications. In this work, a comprehensive review of the state‐of‐the‐art research progress on the promising potential of surface functionalized MXenes as photocatalysts, adsorbents, and membranes for wastewater treatment is presented. The sources, composition, and effects of wastewater on human health and the environment are displayed. Furthermore, the synthesis, surface functionalization, and characterization techniques of merit used in the study of MXenes are discussed, detailing the effects of a range of factors (e.g., PH, temperature, precursor, etc.) on the synthesis, surface functionalization, and performance of the resulting MXenes. Finally, the limits of MXenes and MXene‐based materials as well as their potential future research directions, especially for wastewater treatment applications are highlighted.

This work demonstrates a two-step gram-scale synthesis of presynthesized silver (Ag) nanoparticles impregnated with mesoporous TiO 2 and evaluates their feasibility for wastewater treatment and hydrogen gas generation under natural sunlight. Paracetamol was chosen as the model pharmaceutical pollutant for evaluating photocatalytic performance. A systematic material analysis (morphology, chemical environment, optical bandgap energy) of the Ag/TiO 2 photocatalyst powder was carried out, and the influence of material properties on the performance is discussed in detail. The experimental results showed that the decoration of anatase TiO 2 nanoparticles (size between 80 and 100 nm) with 5 nm Ag nanoparticles (1 wt %) induced visible-light absorption and enhanced charge carrier separation. As a result, 0.01 g/L Ag/TiO 2 effectively removed 99% of 0.01 g/L paracetamol in 120 min and exhibited 60% higher photocatalytic removal than pristine TiO 2 . Alongside paracetamol degradation, Ag/TiO 2 led to the generation of 1729 μmol H 2 g −1 h −1 . This proof-of-concept approach for tandem pollutant degradation and hydrogen generation was further evaluated with rare earth metal (lanthanum)-and nonmetal (nitrogen)-doped TiO 2 , which also showed a positive response. Using a combination of ab initio calculations and our new theory model, we revealed that the enhanced photocatalytic performance of Ag/TiO 2 was due to the surface Fermi-level change of TiO 2 and lowered surface reaction energy barrier for water pollutant oxidation. This work opens new opportunities for exploiting tandem photocatalytic routes beyond water splitting and understanding the simultaneous reactions in metal-doped metal oxide photocatalyst systems under natural sunlight.

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This work reports an environment friendly alternative to epitaxially grow copper oxide nanowires (NWs) on copper substrates using single step atmospheric pressure plasma jet assisted oxidation. NWs of average length 300 nm are grown rapidly in 5 minutes along with transforming the surface to superhydrophilic. This method introduces defects in the nanowire structure which is otherwise difficult to achieve due to the highly isotropic nature of nanowire growth. High resolution transmission electron microscopy reveals vacancies and structural defects such as lattice twinning and kinks. Theoretical investigations using density functional theory calculations indicated that oxygen vacancies reduces the adsorption energy of methanol molecules onto the CuO (111) surface and shifts the Fermi level towards conduction band. During electrocatalysis, these defect-rich nanowires exhibit twice the catalytic activity toward oxygen evolution reaction (OER) and methanol oxidation reaction (MOR) in comparison to the traditionally thermally grown nanowires. Moreover, retreating the electrodes after each stability test drops the contact resistance similar to the prisitine sample. Additionally, these NW photocathodes demonstrate an exceptional photocurrent of 2.2 mAcm -2 and have an excellent degradation activity towards organic pollutants namely phenol and paracetamol. This facile growth method can be used to engineer nanowires of other transition metals with enhanced activities.

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The high interest in the synthesis of mesoporous catalyst demands that novel materials are developed with simple methods capable of improving process yields. In this work, a novel heterogeneous mesoporous catalyst support has been synthesized using mesoporous SBA-15 loaded with mixed bimetal oxides of CeO2 and MgO. Formation of the SBA-15 was actuated in air at room temperature (25°C) and in oven conditions at 100°C after which cerium nitrate and magnesium nitrate precursors were then impregnated into the SBA-15 framework and calcined at 550°C for each of the air and oven crystallization processes. XRD peak patterns confirmed SBA-15 formation and dispersion of nanocrystallites of CeO2 and MgO within the porous framework of SBA-15. Both the air and oven dried processes produced mesoporous MgO-CeO2/SBA-15 catalysts with isotherms that exhibit typical H1 type hysteresis confirming that they possess open-ended cylindrical mesopores. The structural data extracted gave average pore size, pore volume and surface area values in the ranges of 3-5.2 nm, 0.600-2.500 cc/g and 400-500 m2/g respectively which is ideal for several industrial applications.