Introduction: Acute respiratory infections remain one of the main causes of mortality in children aged 0 to 5. This work aimed to study the associated factors with the occurrence of acute respiratory infections in chi...Introduction: Acute respiratory infections remain one of the main causes of mortality in children aged 0 to 5. This work aimed to study the associated factors with the occurrence of acute respiratory infections in children 0 to 5 years old in Yénawa, Cotonou in 2023. Subjects and Method: It was an analytical cross-sectional study of children aged 0 - 5 years and their mothers in Yénawa, selected by four-degree random sampling. The sampling size, calculated using the Schwartz formula, was 126 children and 126 mothers. The dependent variable was the occurrence of acute respiratory infections. The independent variables were classified into four groups: socio-demographic and economic characteristics, behavioral factors, child-related factors, and environmental factors. Data collected by observation and questionnaire survey were analyzed using STATA version 15 software. Associated factors were investigated by bivariate analysis and multiple logistic regression, at the 5% significance level. Results: A total of 126 children aged 0 - 5 years and 126 mothers were surveyed, aged 23.5 (11 - 36) months and 30 (18 - 48) years respectively. The prevalence of acute respiratory infections was 74.60% (CI95% = 66.89 to 82.30). The associated factors were the mother’s age between 18 and 28 (OR = 10.77;CI95% = 1.89 to 61.27;p = 0.007), the use of charcoal/wood for cooking (OR = 7.36;IC = 1.99 to 27.10;p = 0.003)), children's poor personal hygiene (OR = 8.87;IC = 2.92 to 26.97;p 0.001)), and cohabitation with domestic animals (OR = 7.27;IC = 1.67 to 31.71;p = 0.015). Conclusion: Communicating with mothers about the factors identified will help reduce the prevalence of acute respiratory infections in children aged 0 to 5.展开更多
LiNi0. 45 Co0. 10 Mn0. 4sO2 was synthesized from Li2CO3 and a triple oxide of nickel, cobalt and manganese at 950 ℃ in air. The structures and characteristics of LiNi0. 45 Co0.10 Mn0. 45 O2, LiCoO2 and LiMn2 O4 were ...LiNi0. 45 Co0. 10 Mn0. 4sO2 was synthesized from Li2CO3 and a triple oxide of nickel, cobalt and manganese at 950 ℃ in air. The structures and characteristics of LiNi0. 45 Co0.10 Mn0. 45 O2, LiCoO2 and LiMn2 O4 were investigated by XRD, SEM and electrochemical measurements. The results show that LiNi0.4s Co0.10 Mn0. 45 O2 has a layered structure with hexagonal lattice. The commercial LicoO2 has sphere-like appearance and smooth surfaces, while the LiMn2 O4 and LiNi0.45 Co0. 10 Mn0. 45 O2 consist of cornered and uneven particles. LiNi0. 45 Co0.10 Mn0. 45 O2 has a large disLiMn2 O4 and LiCoO2, respectively. LiCoO2 and LiMn2 O4 have higher discharge voltage and better rate-capability than LiNi0. 45Co0.10 Mn0. 45 O2. All the three cathodes have excellent cycling performance with capacity retention of above 89.3 % at the 250th cycle. Batteries with LiMn2 O4 or LiNi0.45 Co0.10 Mn0. 45 O2 cathodes show better safety performance under abusive conditions than those with LiCoO2 cathodes.展开更多
LiNi0. 5 Mn1. 5 O4 was prepared under various conditions by one-step solid-state reaction in air and its properties were investigated by X-ray diffractormetry (XRD), scanning electron microscopy (SEM) and electrochemi...LiNi0. 5 Mn1. 5 O4 was prepared under various conditions by one-step solid-state reaction in air and its properties were investigated by X-ray diffractormetry (XRD), scanning electron microscopy (SEM) and electrochemical measurement. XRD patterns show that LiNi0. 5 Mn1. 5 O4 synthesized under various conditions has cubic spinel structure. SEM images exhibit that the particle size increases with increasing calcination temperature and time. Electro chemical test shows that the LiNi0. 5 Mn1.5 O4 calcined at 700 ℃ for 24 h delivers up to 143 mA · h/g, and the capacity retains 132 mA · h/g after 30 cycles.展开更多
文摘Introduction: Acute respiratory infections remain one of the main causes of mortality in children aged 0 to 5. This work aimed to study the associated factors with the occurrence of acute respiratory infections in children 0 to 5 years old in Yénawa, Cotonou in 2023. Subjects and Method: It was an analytical cross-sectional study of children aged 0 - 5 years and their mothers in Yénawa, selected by four-degree random sampling. The sampling size, calculated using the Schwartz formula, was 126 children and 126 mothers. The dependent variable was the occurrence of acute respiratory infections. The independent variables were classified into four groups: socio-demographic and economic characteristics, behavioral factors, child-related factors, and environmental factors. Data collected by observation and questionnaire survey were analyzed using STATA version 15 software. Associated factors were investigated by bivariate analysis and multiple logistic regression, at the 5% significance level. Results: A total of 126 children aged 0 - 5 years and 126 mothers were surveyed, aged 23.5 (11 - 36) months and 30 (18 - 48) years respectively. The prevalence of acute respiratory infections was 74.60% (CI95% = 66.89 to 82.30). The associated factors were the mother’s age between 18 and 28 (OR = 10.77;CI95% = 1.89 to 61.27;p = 0.007), the use of charcoal/wood for cooking (OR = 7.36;IC = 1.99 to 27.10;p = 0.003)), children's poor personal hygiene (OR = 8.87;IC = 2.92 to 26.97;p 0.001)), and cohabitation with domestic animals (OR = 7.27;IC = 1.67 to 31.71;p = 0.015). Conclusion: Communicating with mothers about the factors identified will help reduce the prevalence of acute respiratory infections in children aged 0 to 5.
基金Project(50302016) supported by the National Natural Science Foundation of China Project(2005037698) supported by the Postdoctoral Science Foundation of China
文摘LiNi0. 45 Co0. 10 Mn0. 4sO2 was synthesized from Li2CO3 and a triple oxide of nickel, cobalt and manganese at 950 ℃ in air. The structures and characteristics of LiNi0. 45 Co0.10 Mn0. 45 O2, LiCoO2 and LiMn2 O4 were investigated by XRD, SEM and electrochemical measurements. The results show that LiNi0.4s Co0.10 Mn0. 45 O2 has a layered structure with hexagonal lattice. The commercial LicoO2 has sphere-like appearance and smooth surfaces, while the LiMn2 O4 and LiNi0.45 Co0. 10 Mn0. 45 O2 consist of cornered and uneven particles. LiNi0. 45 Co0.10 Mn0. 45 O2 has a large disLiMn2 O4 and LiCoO2, respectively. LiCoO2 and LiMn2 O4 have higher discharge voltage and better rate-capability than LiNi0. 45Co0.10 Mn0. 45 O2. All the three cathodes have excellent cycling performance with capacity retention of above 89.3 % at the 250th cycle. Batteries with LiMn2 O4 or LiNi0.45 Co0.10 Mn0. 45 O2 cathodes show better safety performance under abusive conditions than those with LiCoO2 cathodes.
基金Project (76600) supported by Postdoctoral Science Foundation of Central South University
文摘LiNi0. 5 Mn1. 5 O4 was prepared under various conditions by one-step solid-state reaction in air and its properties were investigated by X-ray diffractormetry (XRD), scanning electron microscopy (SEM) and electrochemical measurement. XRD patterns show that LiNi0. 5 Mn1. 5 O4 synthesized under various conditions has cubic spinel structure. SEM images exhibit that the particle size increases with increasing calcination temperature and time. Electro chemical test shows that the LiNi0. 5 Mn1.5 O4 calcined at 700 ℃ for 24 h delivers up to 143 mA · h/g, and the capacity retains 132 mA · h/g after 30 cycles.
