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ObjectiveTo investigate the infection and genotypes of Wolbachia in Aedes albopictus. MethodsAdult and larval samples of Aedes albopictus were collected from different residential and wild areas from 2020 to 2021， Wolbachia surface protein （wsp） gene was amplified and genotyped for wAlbA and wAlbB by PCR， and sequenced for phylogenetic analysis. The difference of detection rate among different habitats， male and female adult mosquitoes， adult and larvae was compared by χ2 analysis. ResultsThe detection rate of Wolbachia in adult and larvae of Aedes albopictus were 43.5% （77/177） and 70.4% （190/270）， respectively， with a statistically significant difference （χ2=32.086，P<0.001）， and wAlbA and wAlbB were mainly detected together. The detection rate of Wolbachia in female and male Aedes albopictus were 50.7% （76/150） and 3.7% （1/27）， respectively， with a statistically significant difference（χ2=20.533，P<0.001）. The detection rate of adult Aedes albopictus in Songjiang wild area， residential area and Hongkou residential area were 91.7% （55/60）， 18.8% （22/117） and 41.7% （30/72）， respectively， with a statistically significant difference （χ2=54.322，P<0.001）. Genotyping and phylogenetic analysis showed that adult and larvae of Aedes albopictus infected with Wolbachia were mainly wAlb A and wAlb B. In addition， some sequences formed clades independently， and the genetic distance from other sequences was relatively large. ConclusionInfection of Wolbachia in Aedes albopictus is relatively common in Songjiang District. The main genotypes are wAlb A and wAlb B and there may be other subtypes， which are worthy of further exploration and research.
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Background Aedes albopictus is the dominant mosquito species in residential areas in Shanghai. There are many types of small containers with accumulated water in residential areas, providing a large number of breeding environments for Aedes alpopicuts and leading to an increasing transmission risk of mosquito-borne diseases. Objective To use random forest to predict breeding of Aedes mosquitoes in small aquatic container habitat in two concentrated reconstruction communities of rural areas in Shanghai, and to understand associated influence of environmental factors on the breeding of Aedes mosquitoes in the process of urbanization.Methods Small-scale habitat surveys of Aedes mosquitoes were carried out in two suburb concentrated reconstruction communities (Community A and B) in Shanghai, and the environment where the habitat was located was recorded and analyzed in both communities. The habitat where eggs, larvae, or pupae were found was recorded as positive. Spatial weight matrix was applied on a household basis, and global Moran's I index was used to carry out spatial autocorrelation analysis on the small-scale habitat and positive habitat in the environment of the two communities. When Moran's I is greater than 0, it means that the data present a positive spatial correlation; when Moran's I is less than 0, it means that the data are spatially negatively correlated; when Moran's I is 0, the spatial distribution is random. Combining the results of P and Z values, we explored the spatial distribution characteristics of small-scale habitat and positive habitat in the community environment. Random forest algorithm in machine learning was used to classify and sort environmental-related factors, and predict the breeding of Aedes mosquitoes in small aquatic habitat; receiver operating characteristic (ROC) curve was used to carry out model fitting evaluation. Results The environmental factors including building location (χ2=23.35, P<0.001), open space (χ2=8.83, P=0.003), and having trees (χ2=11.02, P=0.001) had a significant impact on the positive rate of small-scale habitat. The results of spatial characteristics analysis showed that the global Moran's I index of small-scale habitat was −0.092 (Z=−1.09, P=0.274) in Community A and 0.034 (Z=0.52, P=0.602) in Community B, and the global Moran's I index of positive habitat was −0.092 (Z=−1.14, P=0.255) in Community A and 0.070 (Z=0.95, P=0.342) in Community B. Since the P values of Community A and B were greater than 0.1 and the Z values were between −1.65 and 1.65, for both small-scale habitat and positive habitat the spatial characteristics were randomly distributed and no significant spatial aggregation was found. In the fitted random forest algorithm classification prediction model with the top 10 characteristic factors of importance, the area under curve (AUC) value was 0.95, and the prediction fitting effect was satisfactory. The results of classification and sorting indicated that counts of household small-scale habitat and positive habitat were the most important factors for breeding. Conclusion The random forest model constructed by environmental factor indicators can be used to predict the breeding situation of Aedes mosquitoes in small-scale aquatic habitat, and provide a basis for scientific prevention and control of mosquito breeding for the target area.
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@#Six steroidal saponins were isolated from the n-butanol extract of 90% ethanol extract of the aerial parts of Paris polyphylla var. yunnanensis by silica gel for column chromatography, MCI column chromatography and preparative high performance liquid chromatography (HPLC). According to the physicochemical properties and spectral data, they were identified as 26-O-β-D-glucopyranosyl-kryptogenin-3-O-α-L-rhamnopyranosyl-(1→4)-α-L-rhamnopyranosy-(1→4)-[α-L-rhamnopyranosyl-(1→2)]-β-D-glucopyranoside (1), dioseptemloside G (2), polyphylloside III (3), chonglouoside SL-19 (4), protodioscin (5), chonglouoside SL-5 (6). Among these, compound 1 was a new compound, and compound 2 was obtained from Paris plants for the first time. The platelet aggregation activities and cytotoxicities of the above compounds were evaluated. The results showed that none of the isolated compounds showed significant platelet aggregation activity; compound 2 and 4 exhibited strong cytotoxicity against human colon adenocarcinoma cell line HT29.
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By analyzing data from a questionnaire survey on bilingual teaching, we evalueted the results of bilingual teaching for seven-year medical students and the main problems of bilingual teaching and solutions accordingly. An uneven English level on the part of teachers and students and imperfect materials etc. affect the overall results of bilingual teaching. Therefore persistent efforts need to be made in enhancing the teachers' English level, improving teaching methods and compiling proper textbooks so as to genuinely improve the bilingual teaching program.