Objective:To demonstrate the effect of indoor spraying and window screens on Aedes aegypti mosquito density after space spraying.Methods:A total of 141 households(the study houses)in six communities of Songkhla City,l...Objective:To demonstrate the effect of indoor spraying and window screens on Aedes aegypti mosquito density after space spraying.Methods:A total of 141 households(the study houses)in six communities of Songkhla City,located in Songkhla Province of southern Thailand,were randomly selected and the adult Ae.aegypti populations were assessed pre-and post-insecticide spraying from March to October,2014.Houses close to(within a 20 m radius)the study houses were analyzed using spatial analysis tools.The Aedes aegypti density in the study houses and house density index were compared with the density in the neighbouring houses,based on three spraying conditions:(i)unsprayed(ii)only outdoor sprayed and(iii)indoor plus outdoor sprayed.Results:Only spraying houses indoors was the most effective(P<0.05).There was insufficient evidence that the source of the increase in the number of mosquitoes in unsprayed houses was due to their migration from neighbouring houses which had been sprayed.However,the study houses without screens on their windows were found to have a likely higher dengue vector population after spraying,but the difference was not significant.Conclusions:In dengue endemic areas,all houses should be fully screened and the number of houses ultra-low volume sprayed indoor plus outdoor should be increased with the cooperation of householders and communities during epidemics.展开更多
Partial least squares discriminant analysis (PLS-DA) with integrated moving-window (MW) waveband screening was applied to the discriminant analysis of liquor brands with near-infrared (NIR) spectroscopy. Luzhou Laojia...Partial least squares discriminant analysis (PLS-DA) with integrated moving-window (MW) waveband screening was applied to the discriminant analysis of liquor brands with near-infrared (NIR) spectroscopy. Luzhou Laojiao, a popular liquor with strong fragrant flavor, was used as the identified liquor brand (160 samples, negative, 52 vol alcoholicity). Liquors of 10 other brands with strong fragrant flavor were used as the interferential brands (200 samples, positive, 52 vol alcoholicity). The Kennard-Stone algorithm was used for the division of modeling samples to achieve uniformity and representativeness. Based on the MW-PLS-DA, a simplified optimal model set with 157 wavebands was further proposed. This set contained five types of wavebands corresponding to the NIR absorption bands of water, ethanol, and other micronutrients (i.e., acids, aldehydes, phenols, and aromatic compounds) in liquor for practical choice. Using five selected simple models with 4775 - 4239, 7804 - 6569, 6264 - 5844, 9435 - 7896, and 12066 - 10373 cm-1, the validation recognition rates were obtained as 99.3% or higher. Results show good prediction performance and low model complexity, and also provided a valuable reference for designing small dedicated instruments. The proposed method is a promising tool for large-scale inspection of liquor food safety.展开更多
基金supported by Research Fund,Prince of Songkla University Contract Number MET590137S.
文摘Objective:To demonstrate the effect of indoor spraying and window screens on Aedes aegypti mosquito density after space spraying.Methods:A total of 141 households(the study houses)in six communities of Songkhla City,located in Songkhla Province of southern Thailand,were randomly selected and the adult Ae.aegypti populations were assessed pre-and post-insecticide spraying from March to October,2014.Houses close to(within a 20 m radius)the study houses were analyzed using spatial analysis tools.The Aedes aegypti density in the study houses and house density index were compared with the density in the neighbouring houses,based on three spraying conditions:(i)unsprayed(ii)only outdoor sprayed and(iii)indoor plus outdoor sprayed.Results:Only spraying houses indoors was the most effective(P<0.05).There was insufficient evidence that the source of the increase in the number of mosquitoes in unsprayed houses was due to their migration from neighbouring houses which had been sprayed.However,the study houses without screens on their windows were found to have a likely higher dengue vector population after spraying,but the difference was not significant.Conclusions:In dengue endemic areas,all houses should be fully screened and the number of houses ultra-low volume sprayed indoor plus outdoor should be increased with the cooperation of householders and communities during epidemics.
文摘Partial least squares discriminant analysis (PLS-DA) with integrated moving-window (MW) waveband screening was applied to the discriminant analysis of liquor brands with near-infrared (NIR) spectroscopy. Luzhou Laojiao, a popular liquor with strong fragrant flavor, was used as the identified liquor brand (160 samples, negative, 52 vol alcoholicity). Liquors of 10 other brands with strong fragrant flavor were used as the interferential brands (200 samples, positive, 52 vol alcoholicity). The Kennard-Stone algorithm was used for the division of modeling samples to achieve uniformity and representativeness. Based on the MW-PLS-DA, a simplified optimal model set with 157 wavebands was further proposed. This set contained five types of wavebands corresponding to the NIR absorption bands of water, ethanol, and other micronutrients (i.e., acids, aldehydes, phenols, and aromatic compounds) in liquor for practical choice. Using five selected simple models with 4775 - 4239, 7804 - 6569, 6264 - 5844, 9435 - 7896, and 12066 - 10373 cm-1, the validation recognition rates were obtained as 99.3% or higher. Results show good prediction performance and low model complexity, and also provided a valuable reference for designing small dedicated instruments. The proposed method is a promising tool for large-scale inspection of liquor food safety.
