The atmospheric oxidation mechanism of furan and methylfurans (MFs) initiated by OH radicals is studied using high-level quantum chemistry and kinetic calculations. The reaction starts mainly with OH addition to the C2/C5-position, forming highly chemically activated adduct radical R2*/R5*, which would either be stabilized by collision or promptly isomerize to R2B*/R5B* by breaking the C2-O/C5-O bond and then isomerize to other conformers of R2B/R5B by internal rotations. Under the atmospheric conditions, the ring-retaining radical R2/R5 would recombine with O and be converted to a 5-hydroxy-2-furanone compound and a compound containing epoxide, ester, and carbonyl functional groups, while the ring-opening radicals R2B/R5B would react with O and form unsaturated 1,4-dicarbonyl compounds. RRKM-ME calculations on the fate of R2*/R5* from the addition of OH and furans predict that the fractions of R2B/R5B formation, i.e., the molar yields of the corresponding dicarbonyl compounds, are 0.73, 0.43, 0.26, 0.07, and 0.28 for furan, 2-MF, 3-MF, 2,3-DMF, and 2,5-DMF, respectively, at 298 K and 760 Torr when using the RHF-UCCSD(T)-F12a/cc-pVDZ-F12 reaction energies and barrier heights. The predicted yields for dicarbonyl compounds agree reasonably with recent experimental measurements. Calculations here also suggest high yields of ring-retaining 5-hydroxy-2-furanone compounds, which might deserve further study.

Lumpy skin disease virus (LSDV) is of high economic importance and has spread rapidly to many European and Asian countries in recent years. LSDV was introduced to China in 2019 and have caused severe outbreaks in several provinces. Here, we detected an LSDV strain (GD01/2020) from a cattle farm with typical LSD symptoms in Guangdong, southern China using a novel quantitative real‐time PCR assay targeting the viral GPCR gene. We obtained the whole genomic sequence of GD01/2020 through metagenomic analysis. The GD01/2020 was highly homologous to the LSDVs isolated in Xinjiang, China in 2019, and distinct from all the LSDVs identified in other countries, in their sequences of GPCR and RPO30 genes. The GD01/2020 was a vaccine‐recombinant strain, but distinct from two recombinant LSDVs identified in Russia. At least 25 putative recombination events between a vaccine strain and a field strain were identified in the genome of GD01/2020, which could affect the virulence and transmissibility of the virus. These results suggested that a virulent vaccine‐recombinant LSDV from an unknown origin was introduced into Xinjiang, China in 2019 and spread to Guangdong, China in 2020.

Hepaciviruses represent a group of viruses that pose a significant threat to the health of humans and animals. New members of the genus Hepacivirus in the family Flaviviridae have recently been identified in a wide variety of host species worldwide. Similar to the Hepatitis C virus (HCV), bovine hepacivirus (BovHepV) is hepatotropic and causes acute or persistent infections in cattle. BovHepVs are distributed worldwide and classified into two genotypes with seven subtypes in genotype 1. In this study, three BovHepV strains were identified in the samples of ticks sucking blood on cattle in the Guangdong province of China, through unbiased high-throughput sequencing. Genetic analysis revealed the polyprotein-coding gene of these viral sequences herein shared 67.7–84.8% nt identity and 76.1–95.6% aa identity with other BovHepVs identified worldwide. As per the demarcation criteria adopted for the genotyping and subtyping of HCV, these three BovHepV strains belonged to a novel subtype within the genotype 1. Additionally, purifying selection was the dominant evolutionary pressure acting on the genomes of BovHepV, and genetic recombination was not common among BovHepVs. These results expand the knowledge about the genetic diversity and evolution of BovHepV distributed globally, and also indicate genetically divergent BovHepV strains were co-circulating in cattle populations in China.

No abstract

No abstract