Objective To determine factors influencing rotavirus infection in children in Xi'an. Method Children 5 and under who were diagnosed with rotavirus infection in a hospital in Xi'an from July 2017 to June 2019 were randomly selected as a case group. The children without diarrhea who had physical examinations at the same hospital and the same period were selected as a control group. Two groups were matched by age at a 1∶1 ratio. A questionnaire survey was conducted among parents of two groups of children, including general information of the children and families, feeding habits of primary caregivers, history of rotavirus vaccination, bad habits （such as not washing hands, sucking fingers, etc.）, history of going out , history of contact with diarrhea patients, hygienic conditions （such as diet, toys）. Univariate and multivariate logistic regressions were applied to determine factors influencing rotavirus infection in children. Results This study included 300 parents of children 5 and under （0-59 months） with rotavirus infection in case group and 300 parents of children in control group. There were 168 boys and 132 girls in the case group, with an average age of （15.76 ± 7.52） months and average disease duration of （2.84 ± 2.35） days, ranging 2-7days. The control group had 160 boys and 140 girls, with an average age of （16.53 ± 8.16） months. There were no significant differences in gender composition and mean age between the two groups （P>0.05 for both）. Conditional logistic regression analysis showed that the primary caregivers' education levels were primary school and below （OR=3.330）, history of contact with diarrhea patients （OR=5.114）, bad habits （OR=3.347）, and unclean diet （OR=3.931） were risk factors for rotavirus infection in the children. The primary caregiver occupations being employees of enterprises and institutions （OR=0.154）, service workers （OR=0.168）, freelancers （OR=0.316）, history of rotavirus vaccination （OR=0.131）, good habits of washing hand （OR=0.204）, caregivers washing their hands before feeding （OR=0.401）, and tableware/milk utensils disinfection （OR=0.439） may reduce the risk of rotavirus infection in children 5 and under. Conclusion Low educational level of primary caregivers, history of contact with diarrhea patients, bad habits, and unclean diet are main risk factors for rotavirus infection in infants and young children. It is necessary to carry out easy-to-understand, Objective and direct propaganda and education for caregivers with low education level to improve their health awareness, avoid contacting with diarrhea patients, and cultivate good living habits, so as to reduce the incidence of rotavirus infection in the children.

Objective To investigate the anxiety situation of elder second pregnant women during the last pregnancy period and determine related influencing factors. Method sThe pregnant women with advanced second trimester pregnancy who underwent antenatal checkup were selected from the obstetrics outpatient clinics of two hospitals in Karamay. A questionnaire survey containing the self-rating anxiety scale, pregnancy stress scale, and simplified coping style was conducted. Descriptive epidemiological analysis was used to analyze the results, and multiple linear regression model was performed to determine factors influencing anxiety of pregnant women in the late pregnancy. Results A total of 1 025 second pregnant women during the late trimester of pregnancy in Karamay City was investigated. The pregnant women aged from 35 to 46 years, with an average age of （38.21 ± 2.06） years and gestational age of （33.62 ± 2.75） weeks. Of the participants, 561 （54.7%） had the education level at undergraduate or above, and 713 （69.6%） had the per capita monthly household income ranging from 3,000 to 6,999 Yuan. Anxiety symptoms were found in 403 cases, with an incidence of 39.32%. The pregnancy anxiety score was（49.65 ± 6.87）,with a scoring rate of 62.06%.The stress score was （0.98 ± 0.04）, with a scoring rate of 49.00%. The scores of positive and negative coping styles were （26.32 ± 2.62） and （9.65 ± 1.87）, and the scoring rates were 73.11% and 40.21%, respectively. Multiple regression analysis showed that the greater gestational age （b=3.624）, history of cesarean section （b=4.504）, history of adverse pregnancy and childbirth （b=5.631）, pregnancy complications （b=2.985）, fetal gender expectation （b= 3.652）, medication during pregnancy （b=3.805）, higher score of negative coping （b=5.847）, and higher score of pregnancy stress （b=4.514） were risk factors for anxiety in pregnant women in the third trimester（b=-3.658）; while having assigned person to take special care after delivery （b=-3.658） and better sleep quality （b=-3.587） were protective factors for anxiety in the late pregnancy. Conclusion The elder second pregnant women generally have anxiety during the third trimester of pregnancy, lower pregnancy stress level, and higher level of positive coping in Karamay City. There are many factors influencing anxiety in late pregnancy.

Objective To explore the association between residential environment and two-week prevalence rate of urban residents, so as to provide basis for improving the health status of residents. Method sPermanent residents living in Kunming were selected by using stratified cluster sampling method for questionnaire survey. The survey contents included the residential environment and illness in the past two weeks. Univariate and multivariate logistic regression were used to analyze the effect of residential environment factors on two-week prevalence. Results A total of 2 194 residents in Kunming were investigated in 2016, with an average age of （41.3 ± 20.3） years. Of the participants, 48.36% were males and 51.64% were females; 1 666 （75.93%） aged 15 to 64 years and 265 （12.08%） aged ≥65 years; 1 096 （49.95%） had education level at the junior middle school or below, 1 134 （51.69%） had the average annual income of 10 000 to 59 999 Yuan, and 1 762 （80.31%） were non-smokers. The total two-week prevalence rate was 128.53‰, the two-week prevalence rate of cardiovascular system was highest （67.00 ‰, 147 / 2 194）, and the two-week prevalence rate of hypertension was highest by classification of diseases （60.16 ‰, 132 / 2 194）. The unconditional logistic regression analysis showed residents with per capita living space ≥ 20 m² （OR=0.630） and opening windows frequently for ventilation （OR=0.346） had lower risk of two-week prevalence, while those with traffic artery within the range of 50 meters of their houses （OR=1.552）, applying chemicals related to air pollution （OR=1.922） ,and with a history of chronic disease had higher risk for developing disease within two weeks after adjusting gender, age and chronic disease. Conclusion sResidential environment was associated with the two-week prevalence rate. Measures should be taken to improve the living environment for the health of residents.

Objective To determine factors influencing asthma in children aged 5-14 years in Baoding, so as to provide evidence for preventing the occurrence or recurrence of asthma. Method sChildren aged 5-14 years with asthma admitted to the departments of internal medicine, pediatrics, and emergency of three national asthma sentinel surveillance hospitals in Baoding City in 2018 were selected as the case group. A stratified cluster sampling method was used to select healthy children aged 5-14 years without definite diagnosis of asthma as a control group. A questionnaire survey was conducted among parents of two groups of children, including gender, age, place of residence,breastfeeding time, low birth weight （<2 500 g）, excess nutrients （BMI>24）, family history of asthma, family monthly income, mother's educational level, inhalation of allergens （dust mites, molds, etc.）, food allergy （milk, egg, fish, shrimp, etc.）. The factors influencing asthma were analyzed by multivariate logistic regressions. Result In 2018, 253 children with asthma aged 5 - 14 years who met the inclusion criteria of this study were selected in three national asthma sentinel surveillance hospitals in Baoding City were collected. In the control group, 1 300 healthy children aged 5 - 14 years were selected. The gender ratio of the boys and girls in both the case and control groups was 1∶0.85. There were significant differences between the two groups in the place of residence, breastfeeding time, low birth weight, overnutrition, family history of asthma, family monthly income, maternal education, dust mites allergy, and mold allergy （P<0.05 or P<0.01）. There was no significant difference in the distribution of gender and food allergy history （milk, eggs, fish and shrimp, etc.） （P>0.05 for all）. Multivariate logistic regression analysis showed that the residence in rural area （OR=18.229）, family history of asthma （OR=9.098）, low birth weight （OR=9.545） and overnutrition （OR=8.457） were risk factors of asthma; while the older age （OR = 0.154） and breastfeeding time > 6 months （OR = 0.142） were protective factors for asthma. Conclusion Age, place of residence, family history of asthma, breastfeeding time, low birth weight and overnutrition were factors influencing asthma in children in Baoding. It is recommended to take appropriate measures to reduce the risk of asthma in children.

Objective To investigate the status of abnormal uterine bleeding in female college students and determine its influencing factors, so as to provide scientific basis for reproductive health education in colleges and universities. Method sFemale students were selected by using a stratified cluster sampling method from three vocational schools in Zhaoqing City to conduct a questionnaire survey. The survey included basic information of the respondents, frequency of high-calorie food intake, eating habits, exercise and sleep, and menstruation in the past 6 months. The factors affecting metrorrhagia were analyzed by univariate and multivariate logistic regressions. Results A total of 1 261 female students from three vocational colleges in Zhaoqing City were investigated, including 514 （40.8%） freshmen, 538 （42.7%） sophomores, and 209 （16.6%） juniors. Of the participants, the families of 708 （56.1%） students were in the urban area city, the monthly living expenses of 1 026 （81.4%） were mainly 500-1 499 Yuan, and BMIs of 693 （55.0%） were mainly 18.5-23.9. The prevalence of abnormal uterine bleeding in the respondents was 45.84%. Multivariate logistic regression analysis showed that the female students whose families were located in rural area （OR=1.296）, BMI<18.5 （OR=1.591）, drinking sugary beverage regularly （OR=1.553）, and having weight loss behavior （OR=1.629） had a higher risk of abnormal uterine bleeding, while those who walked regularly had a lower risk （OR=0.648）. Conclusion The incidence of metrorrhagia was high in female college students in Zhaoqing. Regular walking is a favorable factor to reduce the risk of abnormal uterine bleeding in female college students. Students from the rural area, low body mass index, excessive intake of sugary beverage and weight loss may increase the risk of metrorrhagia.

Objective To explore the current situation of capacity building of centers for disease control and prevention （CDCP） at township level in Zhongshan City and find out main problems, so as to provide reference for making policy. Method The current status of disease prevention and control capabilities in Zhongshan City in 2015 and 2018 was investigated, and the results were analyze using descriptive epidemiological analysis methods. Result Twenty-four CDCP at township- level were set up with diverse institutional settings and management models in Zhongshan City in 2018. Of the centers, 54.2% involved 8 or more disease control functions. The business room area increased by 135.57% compared with 2015. At least one vaccination clinic has been set up in each of towns. There were 338 staff members in 2018, a decrease from 355 in 2015. The proportion of staff with a bachelor's degree or above increased from 54.4% to 58.2%, the proportion of staff with an intermediate title or above increased from 4.4% to 27.7%, and the proportion of personnel with less than 5 years of service increased from 17.2% to 29.9%. There were 231 public health doctors in 2018. Of the 24 towns （districts）, 10 （41.7%） were equipped with 1.0 - 1.2 public health doctors per 10,000 population, 10 （41.7%） with 0.5 - 0.9, and 4 （16.7%） with less than 0.5. The score of prevention and control for infectious diseases in 2018 were higher than those in 2015, and the scores of standardized management of immunization in 2018 were lower than those in 2015 （P<0.05 or P<0.01）. Conclusion The capacity building of the township-level CDCP is unbalanced in Zhongshan City. It is suggested that measures of strengthing the responsibility of government input, promoting the substantiation construction of the local CDCP, establishing equitable long-term salary mechanism, personnel training project and other measures should be taken to improve the capacity building.

Objective To study the effect of selenium supplementation on synaptogenesis in hippocampus of offspring mice during pregnancy and lactation.Methods Sodium selenite was supplemented in drinking water from the first day of conception of the female mice, at the doses of 400 μg/L as the low selenium group and 1600 μg/L as the high selenium group. A control group was set up at the same time. The hippocampus of the offspring was separated in 21 days after birth. The density of dendritic spine in hippocampus was observed through Golgistaining. The mRNA expression of synaptic plasticity related genes, such as PSD95, Drebrin and SYN, were detected using RT-PCR, and the protein expression of Drebrin was detected through Western-blot. Result The mice in the control group and the selenium supplement groups had normal diet, normal hair development, luster, good mental state, and were sensitive to general stimuli such as sound and light, without significant difference between the groups. No abortion, stillbirth, dead fetus, or premature death occurred in all groups. There was no significant difference in the number and weight of the offspring between the groups （P>0.05 for all）. The dendritic spines in the hippocampus were regular and dense in the control group and the selenium-enriched groups. After selenium supplementation during pregnancy and lactation, the Golgi-stained dendritic spine count and Drebrin mRNA expression in the DG and CA1 regions of the low and high selenium groups were higher than those of the control group （all P<0.05）, but no significant differences between the low selenium group and high selenium group （both P>0.05）. There was no significant difference in the expression of Drebrin protein between the 3 groups （P>0.05）. Conclusions Selenium supplementation during pregnancy and lactation can promote the formation of synapses in hippocampus of offspring mice. The specific mechanism needs further study.