Objective To study the prevalence and the main risk factors of neonatal asphyxia in southern Gansu province high-altitude area.Method From October 2016 to December 2016,clinical data of neonates born in eight hospitals of the region were analyzed.A uniform questionnaire was used to survey the maternal condition and family background.Univariate and multivariate Logistic regression analysis were used to determine the risk factors of neonatal asphyxia.Result A total of 183 newborns were born with asphyxia (mild 157 cases,severe 26 cases),and the incidence of neonatal asphyxia was 15.3％ (183/1 197).The multivariate Logistic regression analysis indicated that the risk factors included altitude less than 3 000 meters (OR =2.693,95％ CI 1.275 ～5.689),maternal fever (OR =2.986,95％ CI 1.163 ～7.666),prolonged labor (OR =2.925,95％ CI 1.112 ～ 7.691),fetal distress (OR =7.000,95％ CI 3.254 ～ 15.056),uterine inertia (OR =2.737,95％ CI 1.484 ～ 5.047),umbilical cord abnormality (OR =3.094,95％ CI 2.051 ～4.668),amniotic fluid abnormality (OR =2.033,95％ CI 1.230 ～3.361)and placental abnormality (OR =2.753,95％ CI 1.016 ～ 7.464).Annual household income more than 30 000 yuan (OR =0.452,95％ CI 0.297 ～0.687) was protective factor of neonatal asphyxia.Conclusion The incidence of neonatal asphyxia was high in the region,which was related to intrauterine and intrapartum factors.Antepartum monitoring and timely treatment should be strengthened to reduce the incidence of newborn asphyxia.

Objective:To investigate personal exposures to nitrogen oxides(NOX)and nitrogen di-oxide(NO2)and the influence of baseline personal characteristics,living environment and daily activity patterns of the participants on the exposures among adults over 35 in Tianjin and Shanghai.Methods:In this panel study,91 healthy nonsmoking adults aged over 35 from Tianjin and Shanghai participated in our study.The study was conducted in summer and winter.The participants were followed for three times with an interval of at least two weeks.Only participants in Shanghai were followed once in winter because of the COVID-19 pandemic.Twenty-seven participants completed follow-up visits in both seasons.We measured their 24 h personal exposures to NOX and NO2and collected their baseline and time-activity in-formation through questionnaire/diary.The linear mixed model was used to analyze the associations be-tween potential influencing factors and personal NOX and NO2 exposure levels.Results:There were 349 follow-up visits with valid 24 h personal NO2 and NOX exposure measurements in the two cities.The ave-rage 24 h personal exposures to NO2 and NOX(volume fraction)in Tianjin participants were 18.0 x 10-9 and 26.2 × 10-9 in summer,and 31.0 x 10-9 and 54.9 x 10-9in winter,respectively;and the average 24 h personal exposures to NO2 and NOX in Shanghai participants were 38.7 x 10-9and 100.0x10-9in summer,and 45.5 x10-9 and 139.2 x 10-9 in winter,respectively.The results of univariate regression analysis showed that their personal NOX exposure levels were significantly associated with city,season,gender,average daily cooking times,and ambient NO2 concentrations measured at fixed-site monitoring stations.In addition to the above factors,the personal NOX exposure levels were also significantly associ-ated with educational level and the personal NO2 exposure levels were also significantly associated with passive smoking,average daily home time,cooking energy type,residential distance from main traffic road,and use of kitchen ventilators.Multivariate regression analysis showed that the personal exposure levels of NO2 and NOX were significantly lower in Tianjin than that in Shanghai,were significantly lower in summer than that in winter,and were significantly and positively associated with ambient NO2 concen-trations measured at fixed-site monitoring stations.In addition,personal NOX exposure levels were signifi-cantly lower in females than in males,and personal NO2 exposure levels were significantly positively asso-ciated with average daily cooking times and significantly inversely associated with average daily home time.For every interquartile range(IQR)increase(12.7 × 10-9)in ambient NO2,the personal NO2 exposure levels increased by 27.5％(95％CI:17.0％-38.9％),and personal NOX exposure levels in-creased by 16.1％(95％CI:7.1％-25.8％).Conclusion:Season,city and ambient NO2 concentra-tions are significant influencing factors of personal exposure levels of NO2and NOX At the same time,the personal exposures levels of NO2 are also affected by lifestyle factors.Our study provides scientific evi-dence for making precise air pollution control decisions and reducing the exposure levels of NOX in the population.