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Society confronts the pressing environmental challenges posed by the pervasive presence of toxic pollutants in aquatic ecosystems. The repercussions of contaminant release extend far and wide, endangering marine life and human well-being. While various techniques such as bioremediation, filtration, and adsorption have been employed for wastewater treatment, they grapple with cost effectiveness and overall efficiency issues. Advanced oxidative processes, including photocatalysis and Fenton, have emerged as viable solutions in response to the emerging contaminants. However, the efficacy of photocatalysis largely hinges on the choice of catalyst. Their distinctive attributes, such as chemical defects and exceptional stability, make perovskite oxides a promising catalyst. These materials can be synthesized through diverse methods, rendering them versatile and adaptable for widespread applications. Ongoing research endeavors are diligently focused on enhancing the performance of perovskite oxides, optimizing their integration into catalytic processes, and exploring innovative approaches for material immobilization. This comprehensive review seeks to elucidate the most pivotal advances in perovskite oxides and their composites within the wastewater treatment domain. Additionally, it sheds light on burgeoning research trends and multifaceted challenges confronting this field, which present insights into techniques for treating the antibiotic-contaminated environment, delving into innovative strategies, green technologies, challenges, and emerging trends.

Abstract Background The poliovirus has been targeted for eradication since 1988. Kenya reported its last case of indigenous Wild Poliovirus (WPV) in 1984 but suffered from an outbreak of circulating Vaccine-derived Poliovirus type 2 (cVDPV2) in 2018. We aimed to describe Kenya’s polio surveillance performance 2016–2018 using WHO recommended polio surveillance standards. Methods Retrospective secondary data analysis was conducted using Kenyan AFP surveillance case-based database from 2016 to 2018. Analyses were carried out using Epi-Info statistical software (version 7) and mapping was done using Quantum Geographic Information System (GIS) (version 3.4.1). Results Kenya reported 1706 cases of AFP from 2016 to 2018. None of the cases were confirmed as poliomyelitis. However, 23 (1.35%) were classified as polio compatible. Children under 5 years accounted for 1085 (63.6%) cases, 937 (55.0%) cases were boys, and 1503 (88.1%) cases had received three or more doses of Oral Polio Vaccine (OPV). AFP detection rate substantially increased over the years; however, the prolonged health workers strike in 2017 negatively affected key surveillance activities. The mean Non-Polio (NP-AFP) rate during the study period was 2.87/ 100,000 children under 15 years, and two adequate specimens were collected for 1512 (88.6%) AFP cases. Cumulatively, 31 (66.0%) counties surpassed target for both WHO recommended AFP quality indicators. Conclusions The performance of Kenya’s AFP surveillance system surpassed the minimum WHO recommended targets for both non-polio AFP rate and stool adequacy during the period studied. In order to strengthen the country’s polio free status, health worker’s awareness on AFP surveillance and active case search should be strengthened in least performing counties to improve case detection. Similar analyses should be done at the sub-county level to uncover underperformance that might have been hidden by county level analysis.

Different ratios of wax/ethylene vinyl acetate (EVA) and wax/linear low-density polyethylene (LLDPE) blends were prepared using one-step extrusion process to investigate their potential as carrier vehicles for pattern material for investment casting. The thermal, mechanical and rheological properties were characterised. Thermal analysis was done by thermogravimetric analysis (TGA) and differential scanning calorimetry. Mechanical properties were characterised by three-point bending and thermomechanical analysis, whereas the rheological properties were characterised by oscillatory rheometry. The TGA analysis showed that the incorporation of EVA or LLDPE into wax matrix improved the thermal stability properties of the blend. This can be attributed to an enhanced phase adhesion. The melting and solidification behaviour of the blends had intermediate temperatures between wax and EVA. The EVA/wax blends displayed evident viscosity shifts as compared to the viscosity of wax. The incorporation of EVA into wax significantly altered its mechanical properties. Fourier transform infrared spectrometry for both wax/EVA and wax/LLDPE showed a predominant presence of CH2 and carbonyl group in the blend, and the mechanical properties of neat wax were improved when EVA and LLDPE were incorporated into wax. [ABSTRACT FROM AUTHOR]

Society confronts the pressing environmental challenges posed by the pervasive presence of toxic pollutants in aquatic ecosystems. The repercussions of contaminant release extend far and wide, endangering marine life and human well-being. While various techniques such as bioremediation, filtration, and adsorption have been employed for wastewater treatment, they grapple with cost effectiveness and overall efficiency issues. Advanced oxidative processes, including photocatalysis and Fenton, have emerged as viable solutions in response to the emerging contaminants. However, the efficacy of photocatalysis largely hinges on the choice of catalyst. Their distinctive attributes, such as chemical defects and exceptional stability, make perovskite oxides a promising catalyst. These materials can be synthesized through diverse methods, rendering them versatile and adaptable for widespread applications. Ongoing research endeavors are diligently focused on enhancing the performance of perovskite oxides, optimizing their integration into catalytic processes, and exploring innovative approaches for material immobilization. This comprehensive review seeks to elucidate the most pivotal advances in perovskite oxides and their composites within the wastewater treatment domain. Additionally, it sheds light on burgeoning research trends and multifaceted challenges confronting this field, which present insights into techniques for treating the antibiotic-contaminated environment, delving into innovative strategies, green technologies, challenges, and emerging trends. [ABSTRACT FROM AUTHOR]

This work reports on the structural modification of cellulosic materials with magnetic iron oxide nanoparticles through the co-precipitation method. Cellulose is one of the most abundant natural polymers with chemical variability brought about by the presence of several hydroxyl groups, allowing its surface modifications through the insertion of several chemical groups to impact its cellulosic characteristics. Thus, the objective of this study was to synthesize magnetic iron oxide nanoparticles (MNPs) through co-precipitation, followed by in situ incorporation of MNPs onto chemically purified cellulose (CPC) and cellulose nanocrystals (CNC). The composites were characterized for thermal properties using TGA, molecular structure using FTIR, surface morphology using SEM, elemental composition using electron dispersion spectroscopy (EDS), and crystallinity using XRD. The prepared composites presented improved crystal, thermal, and surface properties. CNC-MNPs and CPC-MNPs bore particle sizes of 26.94 and 37.72 nm, respectively, whereas MNPs' particle size was 10.3 nm. EDS analysis indicated that Fe, C, and Cl were the main elements present in the composites. Surface modification of the cellulosic materials presented excellent sorption surface properties and can be used in several industrial processes, such as wastewater purification, air filtration, and various environmental remediation processes. [ABSTRACT FROM AUTHOR]

Paraffin wax‐based compounds are utilized as investment casting pattern materials. This study considered the effect of composition variations on the properties of paraffin wax‐poly(ethylene‐co‐vinyl acetate) (EVA) blends filled with poly(methyl methacrylate) (PMMA) microbeads. The EVA addition significantly improved mechanical properties while the PMMA improved the needle penetration hardness. Both polymers increased the melt viscosity of the wax composition. Thermal gravimetric analysis of the pyrolysis behavior showed that the compounds volatilize readily with virtually no residue remaining above 500 °C. The 40/20/40 wax/EVA/PMMA composition offers a balanced property profile with the bending stress approaching 6 MPa, the bending strain at break exceeding 4%, and a melt viscosity of about 12 Pa s at 90 °C. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48774. [ABSTRACT FROM AUTHOR]