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Riparian zones play a critical role in ecosystems. Accurately extracting the area of a riparian zone in open water is challenging due to human activities and climate change. This study used Sentinel-1 satellite data to investigate the capabilities of the support vector machine, extreme gradient boosting, and random forest methods, which were optimized by genetic algorithms for the detection of area changes in the riparian zone in the heart region of the Three Gorges Reservoir area of China. A total of 29 images were collected in 2020, and three models were created for each image, which were then transferred to other phases. The models’ performance metrics were validated using all of the images. The results indicated that the SVM method achieved the best performance with an accuracy of 0.945, an F1_Score of 0.950, and a kappa coefficient of 0.889. The optimal model was then used to monitor the area changes in the riparian zone over the study area in 2020. It was calculated that the area of the riparian zones was the smallest on 26 December and the largest on 17 June, with a maximum riparian zone of 31.97 km2. Overall, this study demonstrates that an SVM is the most stable method for detecting area changes in a riparian zone when using Sentinel-1 data compared to the RF and XGB methods. The findings are anticipated to provide a feasible plan for detecting the area dynamics in open-water riparian zones and to provide valuable information for the rational utilization of land resources and the ecological safety of the riparian zone in the Three Gorges Reservoir.

Although immune response enhancement has been reported after primary and booster vaccines of CoronaVac, neutralization breadth of SARS-CoV-2 variants is still unclear. In the present study, we examined the neutralization magnitude and breadth of SARS-CoV-2 variants including Beta (B.1.351), Delta (B.1.617.2) and Omicron (B.1.1.529) in 33 convalescent COVID-19 patients and a cohort of 55 medical staff receiving primary CoronaVac vaccines and an additional homologous booster dose. Results showed that, as compared with the two-dose primary vaccination, the homologous booster dose achieved 2.24-, 3.98-, 4.58- and 2.90-fold increase in neutralization titer against wild-type, Beta, Delta, and Omicron, respectively. After booster dose, neutralization titer reduction for variants was less than that after the primary vaccine or that for convalescents. The proportion of recipients able to neutralize 2 or more variants increased from 36.36% post the primary vaccination to 87.27% after the booster. Significant increase in neutralization breadth of 1.24 (95% confidence interval (CI), 0.89–1.59) variants was associated with a log10 increase in neutralization titer against the wild-type. In addition, anti-RBD IgG level was identified as an excellent surrogate for positive neutralization of SARS-CoV-2 and neutralization breadth of variants. These findings highlight the value of an additional homologous CoronaVac dose in broadening the cross-neutralization against SARS-CoV-2 variants, and are critical for informing the booster dose vaccination efforts.

Gap junction protein connexin43 (Cx43), encoded by the GJA1 gene, is the most abundant connexin in the cardiovascular system and was reported as a crucial factor maintaining cardiac electrical conduction, as well as having a very important function in facilitating the recycling of potassium ions from hair cells in the cochlea back into the cochlear endolymph during auditory transduction processes. In mammals, bats are the only taxon possessing powered flight, placing exceptional demand on many organismal processes. To meet the demands of flying, the hearts of bats show many specialties. Moreover, ultrasonic echolocation allows bat species to orientate and often detect and locate food in darkness. In this study, we cloned the full-length coding region of GJA1 gene from 12 different species of bats and obtained orthologous sequences from other mammals. We used the maximum likelihood method to analyse the evolution of GJA1 gene in mammals and the lineage of bats. Our results showed this gene is much conserved in mammals, as well as in bats' lineage. Compared with other mammals, we found one private amino acid substitution shared by bats, which is located on the inner loop domain, as well as some species-specific amino acid substitutions. The evolution rate analyses showed the signature of purifying selection on not only different classification level lineages but also the different domains and amino acid residue sites of this gene. Also, we suggested that GJA1 gene could be used as a good molecular marker to do the phylogenetic reconstruction. [ABSTRACT FROM AUTHOR]