A stochastic epidemic model with two age groups is established in this study,in which the susceptible(S),the exposed(E),the infected(I),the hospitalized(H)and the recovered(R)are involved within the total population,t...A stochastic epidemic model with two age groups is established in this study,in which the susceptible(S),the exposed(E),the infected(I),the hospitalized(H)and the recovered(R)are involved within the total population,the aging rates between two age groups are set to be constant.The existence-and-uniqueness of global positive solution is firstly showed.Then,by constructing several appropriate Lyapunov functions and using the high-dimensional Itô’s formula,the sufficient conditions for the stochastic extinction and stochastic persistence of the exposed individuals and the infected individuals are obtained.The stochastic extinction indicator and the stochastic persistence indicator are less-valued expressions compared with the basic reproduction number.Meanwhile,the main results of this study are modified into multi-age groups.Furthermore,by using the surveillance data for Fujian Provincial Center for Disease Control and Prevention,Fuzhou COVID-19 epidemic is chosen to carry out the numerical simulations,which show that the age group of the population plays the vital role when studying infectious diseases.展开更多
使用均值生成函数、标准正态均一性检验方法和相关分析等方法对我国东部地区96个观测站1931—2020年夏季降水量长年代资料进行了一系列插补、检验、订正及效果分析等工作。结果表明:(1)均值生成函数拟合的1931—2020年各站夏季降水量资...使用均值生成函数、标准正态均一性检验方法和相关分析等方法对我国东部地区96个观测站1931—2020年夏季降水量长年代资料进行了一系列插补、检验、订正及效果分析等工作。结果表明:(1)均值生成函数拟合的1931—2020年各站夏季降水量资料的整体趋势和极值与观测值均有较好的一致性,其中无缺测资料的6个站点观测值和拟合值在距平符号一致率上达到了86.1%,可以满足插补工作的需要。(2)对1931—1950年和1951—2020年2个时段的夏季降水量资料,用平均值和方差2个统计量对插补后的资料进行差异性检验,共有8站具有显著性差异。(3)对插补后的1931—2020年夏季降水量资料进行了均一性检验和均一化订正,其中13站存在非均一性。(4)将订正后的站点资料与CRU_TS4.05(University of East Anglia Climatic Research Unit Global 0.5°Monthly Time Series)数据库的格点资料进行空间分布相似度分析,2套资料在1931—1950、1951—2020和1931—2020年这3个时段的空间相关系数分别达到了0.90,0.92和0.92,空间分布较一致,订正后的资料具有一定的可靠性。展开更多
Totally 150 individuals of 1-day-old Guangxi Jinling partridges were randomly divided into five groups, 30 chickens each group. Chickens in control group were fed with basal diet, while chickens in experimental groups...Totally 150 individuals of 1-day-old Guangxi Jinling partridges were randomly divided into five groups, 30 chickens each group. Chickens in control group were fed with basal diet, while chickens in experimental groups were fed with the diet containing antibiotics, Chinese herbal medicine, probiotics and acidifi- er. The entire trial lasted 50 d, and growth performance and apparent nutrient digestibility of tested chickens were observed and measured. Compared with control group, the feed gain ratio in experimental groups significantly decreased （P 〈 0.05 ）, while that in probiotics group was the lowest. The average daily gain in pmbi- otics group was significantly higher than that in control group or other experimental groups （P 〈 0.05）. The apparent digestibility of crude protein, crude fat and energy in probiotics group were significantly higher than that in control group or other experimental groups （P 〈 0.05 ）. The apparent digestibility of phosphorus, crude fat, crude fiber, calcium and crude protein in antibiotics group were significantly higher than that in control group （P 〈 0.05 ）. The apparent digestibility of crude protein, crude fiber and phosphorus in Chinese herbal medicine group were significantly higher than that in control group （P 〈 0.05 ）. The apparent digesti- bility of nutrient in acidifier group were significantly lower than that in control group or other experimental groups （ P 〈 0.05 ）. Therefore, pmbiotics had better effects on growth performance and apparent nutrient digestibility of chickens than antibiotics, while Chinese herbal medicine and acidifier had inferior effect than an- tibiotics.展开更多
基金Supported by National Natural Science Foundation of China(61911530398,12231012)Consultancy Project by the Chinese Academy of Engineering(2022-JB-06,2023-JB-12)+3 种基金the Natural Science Foundation of Fujian Province of China(2021J01621)Special Projects of the Central Government Guiding Local Science and Technology Development(2021L3018)Royal Society of Edinburgh(RSE1832)Engineering and Physical Sciences Research Council(EP/W522521/1).
文摘A stochastic epidemic model with two age groups is established in this study,in which the susceptible(S),the exposed(E),the infected(I),the hospitalized(H)and the recovered(R)are involved within the total population,the aging rates between two age groups are set to be constant.The existence-and-uniqueness of global positive solution is firstly showed.Then,by constructing several appropriate Lyapunov functions and using the high-dimensional Itô’s formula,the sufficient conditions for the stochastic extinction and stochastic persistence of the exposed individuals and the infected individuals are obtained.The stochastic extinction indicator and the stochastic persistence indicator are less-valued expressions compared with the basic reproduction number.Meanwhile,the main results of this study are modified into multi-age groups.Furthermore,by using the surveillance data for Fujian Provincial Center for Disease Control and Prevention,Fuzhou COVID-19 epidemic is chosen to carry out the numerical simulations,which show that the age group of the population plays the vital role when studying infectious diseases.
文摘使用均值生成函数、标准正态均一性检验方法和相关分析等方法对我国东部地区96个观测站1931—2020年夏季降水量长年代资料进行了一系列插补、检验、订正及效果分析等工作。结果表明:(1)均值生成函数拟合的1931—2020年各站夏季降水量资料的整体趋势和极值与观测值均有较好的一致性,其中无缺测资料的6个站点观测值和拟合值在距平符号一致率上达到了86.1%,可以满足插补工作的需要。(2)对1931—1950年和1951—2020年2个时段的夏季降水量资料,用平均值和方差2个统计量对插补后的资料进行差异性检验,共有8站具有显著性差异。(3)对插补后的1931—2020年夏季降水量资料进行了均一性检验和均一化订正,其中13站存在非均一性。(4)将订正后的站点资料与CRU_TS4.05(University of East Anglia Climatic Research Unit Global 0.5°Monthly Time Series)数据库的格点资料进行空间分布相似度分析,2套资料在1931—1950、1951—2020和1931—2020年这3个时段的空间相关系数分别达到了0.90,0.92和0.92,空间分布较一致,订正后的资料具有一定的可靠性。
基金Supported by Program for Science and Technology Development of Guangxi Province(1123007-1)China Agricultural Industry Research System"Special Project for Guangxi Broiler Industry Innovation Team"(nycytxgxcxtd-04-20)
文摘Totally 150 individuals of 1-day-old Guangxi Jinling partridges were randomly divided into five groups, 30 chickens each group. Chickens in control group were fed with basal diet, while chickens in experimental groups were fed with the diet containing antibiotics, Chinese herbal medicine, probiotics and acidifi- er. The entire trial lasted 50 d, and growth performance and apparent nutrient digestibility of tested chickens were observed and measured. Compared with control group, the feed gain ratio in experimental groups significantly decreased （P 〈 0.05 ）, while that in probiotics group was the lowest. The average daily gain in pmbi- otics group was significantly higher than that in control group or other experimental groups （P 〈 0.05）. The apparent digestibility of crude protein, crude fat and energy in probiotics group were significantly higher than that in control group or other experimental groups （P 〈 0.05 ）. The apparent digestibility of phosphorus, crude fat, crude fiber, calcium and crude protein in antibiotics group were significantly higher than that in control group （P 〈 0.05 ）. The apparent digestibility of crude protein, crude fiber and phosphorus in Chinese herbal medicine group were significantly higher than that in control group （P 〈 0.05 ）. The apparent digesti- bility of nutrient in acidifier group were significantly lower than that in control group or other experimental groups （ P 〈 0.05 ）. Therefore, pmbiotics had better effects on growth performance and apparent nutrient digestibility of chickens than antibiotics, while Chinese herbal medicine and acidifier had inferior effect than an- tibiotics.
