Nanopore targeted sequencing (NTS) is reported to be advantageous in detection speed and range over culture in prior published reports. Investigation of the clinical performance of NTS is deficient at present.

Background: Staphylococcus aureus (S. aureus) was able to rapidly evolve and adapt under the pressure of antibiotics, host immune and environmental change. After Corona Virus Disease 2019 (COVID-19) epidemic in Wuhan, China, a large number of disinfectants were used, which might result in rapid evolution of S. aureus. Methods: A total of 619 S. aureus isolates were collected from Zhongnan Hospital, Wuhan University from 2018 to 2021, including group BEFORE (309 strains collected before COVID-19 pandemic) and group AFTER (310 strains collected after COVID-19 pandemic), for comparing the changes of molecular epidemiology. The molecular characteristics of isolates were analyzed by Multilocus sequence typing (MLST), spa, chromosomal cassette mec (SCCmec) typing, virulence genes were screened by the PCR, antibiotic susceptibility test was carried out by the VITEK system. Results: Thirty-six sequence types (STs) belonging to 14 clone complexes (CCs) were identified. ST5 was the most prevalent clone in both groups, and ST7, ranking the sixth in group BEFORE, became the second dominant clone in group AFTER (6.5% vs 10.0%), whereas ST239 decreased from the seventh to the fourteenth (5.8% vs 1.9%). ST7 in group AFTER had a higher positive rate of virulence genes, including hlb, fnbB, seb, lukDE, sdrE and the proportion of ST7-t091 MRSA strains increased from 19.1% to 50% compared with group BEFORE. Though no significant difference of MRSA proportion was found between two groups, SCCmec type-III in group AFTER decreased (p<0.01). Though the rate of multidrug-resistance (MDR) decreased, the virulence genes hlb, hlg, fnbB, seb and pvl carrying rates were significantly elevated in MRSA strains of group AFTER. Conclusion: After COVID-19 pandemic, ST7 becomes one of the predominant S. aureus clones in Wuhan and the carrying rate of SCCmec and virulence genes is on the rise. Therefore, it is essential to strengthen the surveillance of ST7 S. aureus clone.

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High-entropy alloy (HEA) coatings demonstrate excellent corrosion resistance and wear resistance. However, their applications are limited owing to a complicated process and high costs. In the present work, an FeCrNiMnAl HEA coating was synthesised by spray deposition combining with thermite reaction using a mixture of Fe 2 O 3 , CrO 3 , MnO 2 , Ni, and Al powders as precursors. After spray deposition, the as-formed coating layer consisted of two bodycentred cubic phases, and showed good metallurgical bonding with the substrate. The average microhardness value of the FeCrNiMnAl HEA coating reached 432.2 ± 10.8 HV, which was higher than that of the substrate (259.5 ± 8.4 HV). The coating also exhibited superior wear resistance and corrosion resistance compared with the substrate. This method has great potential for preparing HEA coatings.

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