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The COVID-19 pandemic across Chinese mainland was gradually stabilized at a low level with sporadic outbreaks, before the emergence of Omicron variant. Apart from non-pharmacological interventions (NPIs), COVID-19 vaccine has also been implemented to prevent and control the pandemic since early 2021. Although many aspects have been focused, the change of the spatiotemporal distribution of COVID-19 epidemic across Chinese mainland responding to the change of prevention and control measures were less concerned. Here, we collected the confirmed case data (including domestic cases and overseas imported cases) across Chinese mainland during both 2020/04–2020/08 and 2021/04–2021/08, and then conducted a preliminary data comparison on the spatiotemporal distribution of confirmed cases during the identical period between the two years. Distribution patterns were evaluated both qualitatively by classification method and quantitatively through employing coefficient of variation. Results revealed significant differences in the homogeneity of spatiotemporal distributions of imported or domestic cases between the two years, indicating that the important effect of the adjustment of prevention and control measures on the epidemic evolution. The findings here enriched our practical experience of COVID-19 prevention and control. And, the collected data here might be helpful for improving or verifying spatiotemporally dynamic models of infectious diseases. [ABSTRACT FROM AUTHOR]

Strawberry vein banding virus (SVBV) is one of the serious viral pathogens infecting strawberry worldwide. To understand the molecular characterization of SVBV from China, complete genome sequences of sixteen SVBV isolates were cloned and sequenced. Sequence comparison showed they shared high nucleotide sequence identity (93.6–99.5%) with isolates from China and Japan (96.6–98.4%), while relatively low identity with the isolates from Canada (91.9–93.7%) and USA (85.5–85.9%). Phylogenetic analyses based on the complete genome sequence or coat protein (CP) gene showed the SVBV isolates clustered into three clades correlated with geographic distribution. Recombination analyses identified 13 recombinants and 21 recombinant events, indicating frequent and multiple recombinations in SVBV evolution. Furthermore, a sensitive loop-mediated isothermal amplification (LAMP) method was developed for rapid detection of SVBV isolates, which could be especially suitable for seedling propagation, virus-free culture and routine diagnostics in field investigation. This study offers new understanding of the molecular evolution and may help to improve the management of SVBV. [ABSTRACT FROM AUTHOR]

Sorghum ratooning, a time and labor-saving cultivation practice, is increasingly being adopted by farmers in Southwest China as an alternative. Efficient N fertilizer management is critical for economical production of sorghum and the long-term protection of the environment. To investigate the impact of N management on grain yield and nitrogen use efficiencies (NUEs) of ratoon sorghum system, a three-year field experiment was conducted for Jinyunuo3 (a hybrid cultivar) and Guojiaohong1 (an inbred cultivar) using 12 combinations of N rates and splitting ratios. The results showed that increasing N rate and splitting application times led to improvements in various growth parameters such as dry matter weight, crop growth rate (CGR), leaf area index (LAI), and photosynthetic potential (PP). The main, ratoon, and annual yields increased with N rate increase, but there was no significant difference between 225 and 150 kg N ha -1 in the ratoon and annual yields. Splitting the application of N fertilizer enhanced grain yield compared to a single dose application method, especially three-split applications yielded higher than two-split applications. Compared with N rates of 225 and 150 kg ha -1 , N rate of 75 kg ha -1 increased apparent recovery rate of applied nitrogen (RE N ), agronomic efficiency of applied nitrogen (AE N ), and partial factor productivity from applied nitrogen (PFP N ) in both main season and whole year. But through splitting application methods at high N rates could achieve similar or even higher levels of NUEs compared to all applied as basal fertilizer at low N rates. Therefore, it could be recommended that applying 150 kg N ha -1 with a basal-jointing-heading fertilizer ratio of 2:4:4 represented an efficient N management practice to synchronously obtain high grain yield and NUEs in ratoon sorghum system in Southwest China., (© 2024. The Author(s).)

Multiple infections are a key component of HPV pathogenesis and have a direct impact on how an infection turns out. It's crucial to look at the associations between HPV multiple infections and both age and HPV genotypes in the Chinese population, searching for the causative factors of multiple infections with a view to providing new ideas for the treatment and prevention of multiple infections. In this study, we retrospectively analyzed the data of HPV infections among outpatients from the 2019 year to the 2021 year of Shandong Maternal and Child Health Hospital. Analyzed the correlation between HPV multiple infections and age using logistic regression. Differences in the percentage of multiple infections between age groups were compared using the chi-square test. The chi-square test compared the differences in the distribution of 15 common HPV genotypes in mono- versus multiple infections. A two-dimensional matrix presented the frequency of HPV genotype combinations. Logistics regression analysis showed that age was significantly associated with the occurrence of multiple infections, with a dominance ratio OR 1.026 (95% CI 1.02-1.04). Interestingly, the proportion of HPV multiple infections among HPV-positive individuals increases with age in people older than 30 years of age. The chi-square test showed there was a difference in the distribution of HPV genotypes between multiple infections and mono- HPV infection (χ 2  = 76.4; p = 0.000), a difference in the composition of HPV genotypes for dual versus single infections (χ 2  = 90.6; p = 0.000) and a difference in HPV genotypes for triple versus single infections (χ 2  = 56.7; p = 0.000). A 2 × 2 matrix showed that the combination of HPV52/HPV58 (30; 6.4%) was the combination of the highest frequency of infection for dual infections; The HPV52/HPV58 (21; 4.8%) combination was the highest frequency of HPV triple infection combination. HPV multiple infections were positively correlated with age; increasing age was positively correlated with the proportion of HPV multiple infections in the total infected population; the distribution of the 15 common genotypes of HPV differed between multiple infections and single infections; and HPV52:58 was a common type of infection combination in the Shandong population., (© 2024. The Author(s).)