AIM To investigate the prevalence and related risk factors of birth defects in Shanghai. METHODS This report describes a population-based study of all births at the Obstetrics and Gynecology Hospital of Fudan Universi...AIM To investigate the prevalence and related risk factors of birth defects in Shanghai. METHODS This report describes a population-based study of all births at the Obstetrics and Gynecology Hospital of Fudan University in Shanghai, China from January 2008 to December 2014. A logistic regression analysis was used to identify the parameters that are independently associated with birth defects. RESULTS A total of 82814 births, including 824 cases of birth defects, were recorded. The rate of birth defects was 0.995 per 100 births. In the multivariable regression analysis, neonatal birth defects were likely to be associated with higher gravidity [odds ratio(OR), 1.099, 95%CI: 1.024-1.178], premature birth(OR = 1.905, 95%CI: 1.501-2.418), low birth weight(OR = 3.844, 95%CI: 3.004-4.919), twin births or higher order multiple pregnancies(OR = 1.477, 95%CI: 1.107-1.969), cesarean delivery(OR = 1.184, 95%CI: 1.016-1.380) and registration as part of a migrant population(OR = 1.380, 95%CI: 1.167-1.632). Female infants were less likely to have birth defects than male infants(OR = 0.710, 95%CI: 0.616-0.818). CONCLUSION Higher gravidity, premature birth, lower birth weight,twin births or higher order multiple pregnancies, and registration as part of a migrant population are independent predictors of birth defects.展开更多
Objective:Some pregnancy complications are associated with respiratory problems in infants.Early identification and implementation of respiratory support are needed for these infants.This study aimed to(1)use lung ult...Objective:Some pregnancy complications are associated with respiratory problems in infants.Early identification and implementation of respiratory support are needed for these infants.This study aimed to(1)use lung ultrasound(LU)for predicting the respiratory support requirements of infants and(2)simplify the examination method to facilitate its clinical application.Methods:Neonates underwent LU examinations within 1 hour of birth.The infants were divided into a pregnancy complication(PC)group and a control group according to their mothers'clinical data.The primary outcome measure was the need for respiratory support.Predictive models were established based on the differences in LU patterns between the two groups.The predictive value of the models was compared with that of the LU score(LUS)system,which has been widely used in other studies.Simplified models were established by analyzing the predictive effects of LU patterns in different parts of the lungs.Predictive reliability was tested using the receiver operating characteristic curve analysis.Results:PC and control groups had 29 and 117 neonates,respectively;a total of 22 neonates required respiratory support.The PC and control groups showed differences in respiratory support requirements,A-lines,and coalesced B-lines.The percentages of A-lines and coalesced B-lines were associated with respiratory support requirements.The optimal cutoff values for the percentages of the A-lines and coalesced B-lines were 55.7%and 24.5%,respectively.Similar effects were obtained by calculating the percentage of coalesced B-lines in four areas(R3,R4,L3,and L4).These methods were judged as more visual and convenient than LUS assessment.conclusion:The percentages of A-line and coalesced B-lines on LU images can be used to predict the respiratory support needs of neonates whose mothers had pregnancy complications.Only four areas(R3,R4,L3,and L4)had similar predictive values.展开更多
To enhance nominal current of high voltage vacuum circuit breakers （VCBs）, a gravity heat pipe was proposed to replace stationary conducting rod of a high voltage vacuum interrupter. The heat pipe is composed of two...To enhance nominal current of high voltage vacuum circuit breakers （VCBs）, a gravity heat pipe was proposed to replace stationary conducting rod of a high voltage vacuum interrupter. The heat pipe is composed of two coaxis tubes： the external tube is made of oxygen-free copper and the inner tube is made of stainless steel. The bottom end of the inner stainless steel tube is connected to the external copper tube by holes. Transient and static thermal performance of the heat pipe was measured, and the thermal resistance of it was compared with that of a solid copper rod with the same dimensions. Experimental results showed that thermal resistance of the heat pipe was about 1/3 of that of the copper rod, and it decreased slightly with the rising of the input heat flux. 3D thermal simulation on a 126 kV/2000 A single break VCB was done to compare the thermal performance between the proposed gravity heat pipe and the copper rod serving as the stationary conducting rod of the vacuum interrupter. Simulation results revealed that in the heat pipe case, the maximum temperature between contacts was 67 ℃ lower than that in the copper rod case.展开更多
文摘AIM To investigate the prevalence and related risk factors of birth defects in Shanghai. METHODS This report describes a population-based study of all births at the Obstetrics and Gynecology Hospital of Fudan University in Shanghai, China from January 2008 to December 2014. A logistic regression analysis was used to identify the parameters that are independently associated with birth defects. RESULTS A total of 82814 births, including 824 cases of birth defects, were recorded. The rate of birth defects was 0.995 per 100 births. In the multivariable regression analysis, neonatal birth defects were likely to be associated with higher gravidity [odds ratio(OR), 1.099, 95%CI: 1.024-1.178], premature birth(OR = 1.905, 95%CI: 1.501-2.418), low birth weight(OR = 3.844, 95%CI: 3.004-4.919), twin births or higher order multiple pregnancies(OR = 1.477, 95%CI: 1.107-1.969), cesarean delivery(OR = 1.184, 95%CI: 1.016-1.380) and registration as part of a migrant population(OR = 1.380, 95%CI: 1.167-1.632). Female infants were less likely to have birth defects than male infants(OR = 0.710, 95%CI: 0.616-0.818). CONCLUSION Higher gravidity, premature birth, lower birth weight,twin births or higher order multiple pregnancies, and registration as part of a migrant population are independent predictors of birth defects.
基金supported by the Shanghai Municipal Health Commission(202040402)。
文摘Objective:Some pregnancy complications are associated with respiratory problems in infants.Early identification and implementation of respiratory support are needed for these infants.This study aimed to(1)use lung ultrasound(LU)for predicting the respiratory support requirements of infants and(2)simplify the examination method to facilitate its clinical application.Methods:Neonates underwent LU examinations within 1 hour of birth.The infants were divided into a pregnancy complication(PC)group and a control group according to their mothers'clinical data.The primary outcome measure was the need for respiratory support.Predictive models were established based on the differences in LU patterns between the two groups.The predictive value of the models was compared with that of the LU score(LUS)system,which has been widely used in other studies.Simplified models were established by analyzing the predictive effects of LU patterns in different parts of the lungs.Predictive reliability was tested using the receiver operating characteristic curve analysis.Results:PC and control groups had 29 and 117 neonates,respectively;a total of 22 neonates required respiratory support.The PC and control groups showed differences in respiratory support requirements,A-lines,and coalesced B-lines.The percentages of A-lines and coalesced B-lines were associated with respiratory support requirements.The optimal cutoff values for the percentages of the A-lines and coalesced B-lines were 55.7%and 24.5%,respectively.Similar effects were obtained by calculating the percentage of coalesced B-lines in four areas(R3,R4,L3,and L4).These methods were judged as more visual and convenient than LUS assessment.conclusion:The percentages of A-line and coalesced B-lines on LU images can be used to predict the respiratory support needs of neonates whose mothers had pregnancy complications.Only four areas(R3,R4,L3,and L4)had similar predictive values.
基金Project (No. 200806981005) supported by the New Teacher Foundation of MOE, China
文摘To enhance nominal current of high voltage vacuum circuit breakers （VCBs）, a gravity heat pipe was proposed to replace stationary conducting rod of a high voltage vacuum interrupter. The heat pipe is composed of two coaxis tubes： the external tube is made of oxygen-free copper and the inner tube is made of stainless steel. The bottom end of the inner stainless steel tube is connected to the external copper tube by holes. Transient and static thermal performance of the heat pipe was measured, and the thermal resistance of it was compared with that of a solid copper rod with the same dimensions. Experimental results showed that thermal resistance of the heat pipe was about 1/3 of that of the copper rod, and it decreased slightly with the rising of the input heat flux. 3D thermal simulation on a 126 kV/2000 A single break VCB was done to compare the thermal performance between the proposed gravity heat pipe and the copper rod serving as the stationary conducting rod of the vacuum interrupter. Simulation results revealed that in the heat pipe case, the maximum temperature between contacts was 67 ℃ lower than that in the copper rod case.
