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ObjectiveTo analyze the whole-genome characteristics of four coxsackievirus B5 (CVB5) strains isolated in Yunnan province, China in 2022. MethodsPrimers were designed to amplify and sequence the whole genome of CVB5 isolates. The whole genome was amplified in segments, and sequenced using the "primer walking" method. Sequence splicing and assembly were performed. Genetic characteristics of the CVB5 strains were analyzed using software such as MEGA 7.0, Simplot 3.5.1, and DNAStar 7.1. ResultsBased on VP1 and whole-genome phylogenetic analysis, all four CVB5 isolates belonged to genotype C. Compared with the prototype strain, multiple amino acid mutations occurred in the VP1 region of the four strains. Phylogenetic analysis of P1, P2, and P3 regions and Simplot recombination analysis showed that the CVB5 isolates in this study may have undergone recombination with multiple enterovirus B strains. ConclusionThe four CVB5 strains isolated from clinical samples of hand, foot and mouth disease (HFMD) patients in Kunming, Yunnan province in 2022 all belonged to genotype C.

Fly ash was modified by the alkali washing and calcium oxide calcining method The infrared spectrometer and scanning electron microscopy were used to characterize the bond groups and morphology before and after modification fly ash. The dosage, pH, calcined temperature and adsorption time were used as variable factors to adsorb Cr (VI)-containing waste water. The results showed that the removal rate of Cr(VI) can reach 96.38% under modified fly ash dosage at 6 g/L, initial pH value at 8, secondary calcination temperature at 800℃ and the ratio with calcium oxide at 3∶1. The adsorption capacity reached 16.06 mg/g. The kinetic fitting process shows that the adsorption of Cr (VI) by the modified fly ash conformed to the pseudo-second-order kinetic equation. This process was dominated by chemical adsorption and continuous.