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Eliminating mother-to-child transmission of HBV: progress and challenges in China

Wenzhan Jing, Jue Liu, Min Liu

《医学前沿（英文）》 2020年 第14卷 第1期   页码 21-29 doi: 10.1007/s11684-020-0744-2

摘要： China has the world’s largest burden of hepatitis B virus (HBV) infection, but the country has made considerable progress in preventing its mother-to-child transmission (MTCT) in the past three decades. This feat is made possible due to the high coverage of birth-dose hepatitis B vaccine (HepB,>95%), hepatitis B surface antigen (HBsAg) screening for pregnant women (>99%), and hepatitis B immunoglobulin plus HepB for newborns whose mothers are HBsAg positive (>99%). Studies on the optimal antiviral treatment regimen for pregnant women with high HBV-DNA load have also been conducted. However, China still faces challenges in eliminating MTCT of HBV. The overall HBsAg prevalence among pregnant women is considered an intermediate endemic. The prevalence of HBsAg among pregnant women from remote, rural, or ethnic minority areas is higher than that of the national level because of limited health resources and public health education for HBV. The coverage for maternal and child healthcare and immunization services should be improved, especially in western regions. Integration of current services to prevent MTCT of HBV with other relevant health services can increase the acceptability, efficiency, and coverage of these services, particularly in remote areas and ethnic minority areas. By doing so, progress toward key milestones and targets to eliminate hepatitis B as the main public health threat by 2030 can be achieved.

关键词： hepatitis B virus     mother-to-child transmission     progress     challenge    

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Current recommendations of managing HBV infection in preconception or pregnancy

null

《医学前沿（英文）》 2014年 第8卷 第2期   页码 158-165 doi: 10.1007/s11684-014-0340-4

摘要：

Hepatitis B remains a leading cause of cirrhosis, hepatocellular carcinoma and liver transplantation worldwide. Management of chronic hepatitis B during pregnancy is challenging. Transmission of hepatitis B to infants still occurs perinatally although immunoprophylaxis is widely available for infants born to mothers with chronic hepatitis B infection. The emerging data suggest that initiation of antiviral therapy in the beginning of the third trimester in highly viremic mothers can prevent immunoprophylaxis failure in their infants. The available drug safety data show that lamivudine, telbivudine and tenofovir are generally safe to be used during the pregnancy. In order to minimize the fetal exposure to the antiviral medication, antiviral therapy during the pregnancy should be limited to a selected group of patients with cirrhosis, high hepatitis B viral load, or prior history immunoprophylaxis failure. An elective Caesarean section may reduce the risk of perinatal transmission. For those females planning for pregnancy or in early stage of pregnancy, communication and follow-up among obstetrician, gastroenterologist, and primary care physician are important. In this article, we will review the features of hepatitis B infection before, during and after the pregnancy; the risk factors that increase mother-to-child transmission; safety data on antiviral drug use during pregnancy; and the potential role of Caesarean section in selected cases.

关键词： antiviral therapy     Caesarean section     cirrhosis     hepatitis B     immunoprophylaxis     mother-to-child transmission     pregnancy     prevention    

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New medical risks affecting obstetrics after implementation of the two-child policy in China

null

《医学前沿（英文）》 2017年 第11卷 第4期   页码 570-575 doi: 10.1007/s11684-017-0552-5

摘要：

China recently instituted a two-child policy in response to its aging population, declining workforce and demographic dividend, and the need to develop asocial economy. Additionally, women generally delay having a second child because of the overwhelming pressure in their lives. With the improvements in assisted fertility technologies in recent years, the number of elderly women attempting to bear children has increased. The quality of woman’s eggs and a man’s sperm declined dramatically with increasing age, leading to an increased risk of pregnancy-related complications among older women. Therefore, the types of fertility problems experienced by elderly females must be provided with considerable attention by obstetricians. This commentary article focuses on the medical problems faced by older second-child pregnant women. This work discusses their increased rates of infertility, spontaneous abortion, fetal malformation, gestational diabetes, cesarean section, placenta previa, postpartum hemorrhage, postpartum depression, and hypertensive disorders, which complicate pregnancy.

关键词： two-child policy     birth defects     cesarean delivery     placenta previa    

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Optimization of the O/HO process with response surface methodology for pretreatment of mother liquor

《环境科学与工程前沿（英文）》 2021年 第15卷 第4期 doi: 10.1007/s11783-020-1371-5

摘要：

• Real ML-GFW with high salinity and high organics was degraded by O3/H2O2 process.

关键词： High salinity     High organic matters     Gas field wastewater     O3/H2O2     Response surface methodology    

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育龄妇女非意愿妊娠原因分析与对策研究

王代权,刘长艳,向琼,马代慈

《中国工程科学》 2014年 第16卷 第5期   页码 11-15

摘要：

采取整群抽样调查方法，对2011 年1 月—2013 年5 月在秭归县、夷陵区计划生育服务站因非意愿妊娠而实行人工终止妊娠对象，通过查阅病历资料和调查问卷，了解非意愿性妊娠原因及相关因素。1 360例非意愿妊娠中，未婚为21.62 %，已婚为78.38 %；人群分布在20～39 年龄段（73.82 %）；孕次分布主要在孕2～孕3 的对象为57.87 %；非意愿妊娠中避孕措施失败者为44.34 %，无措施者为55.66 %。避孕措施因素宫内节育器为10.51 %，避孕套为10.51 %，避孕药为8.24 %，外用为6.62 %，其他为8.46 %。存在侥幸心理和取出宫内节育器（IUD）后续措施没能跟进是无措施者导致非意愿妊娠的主要原因。避孕知识知晓率为98.90 %，对紧急避孕的知晓率仅为15.37 %，知道哺乳期需避孕者为18.38 %。医务人员、计生干部、宣传资料是已婚人群获取避孕知识的主要途径，农民及农民工对象获取免费服务高于城镇居民、国家工作人员、商业服务人员及外来流入人员。

关键词： 育龄妇女     非意愿妊娠     人工流产     影响因素    

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Relationship between selenium concentration in child hair and the distribution of Kashin-Beck Disease

LI Shunjiang, YANG Linsheng, WANG Wuyi, LI Yonghua, LI Hairong, XIRAO Ruodeng

《医学前沿（英文）》 2007年 第1卷 第2期   页码 223-225 doi: 10.1007/s11684-007-0043-1

摘要： The focus of this study is to determine the relationship between selenium (Se) concentrations in child hair and the distribution of Kashin-Beck disease (KBD) in Tibet. The hair of children in typical KBD-affected areas and non-disease areas was collected, and its Se concentrations were measured by atomic fluorescent spectrometry. The Se concentrations in child hair were (0.13±0.04) and (0.18±0.07) µg/g respectively in KBD areas and non-disease areas respectively, which are significantly different. In areas supplemented with Se in Tibet, the Se concentration of hair in KBD- affected areas was higher than that in non-diseased areas, being (0.28±0.03) and (0.18±0.04) µg/g respectively. There is a close relationship between the Se concentrations in hair and KBD distribution. Se supplement increase the Se concentrations in the human body. Appropriate Se supplementation is important to prevent KBD in Tibet.

关键词： different     relationship     non-disease     selenium     KBD distribution    

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儿童乘员约束系统研究现状与展望

方园,吴光强

《中国工程科学》 2006年 第8卷 第8期   页码 81-85

摘要：

儿童乘员约束系统也称儿童安全座椅，是一项新兴的研究领域。随着儿童乘员数量的上升，对于能够有效地保护儿童乘员安全的约束系统的研究具有特殊的重要意义。介绍了儿童乘员约束系统与成人乘员约束系统在分类和组成上的区别，以及相应的发展和健全的安全法规；展望了先进的设计理论、计算机仿真技术应用和系统型研究策略给儿童乘员约束系统研究开辟的前景。

关键词： 儿童乘员约束系统     安全座椅     台车试验     伤害评价指标     评价程序    

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广州市“单独二孩”登记群体特征分析

唐运革,李飞成,韩立薇

《中国工程科学》 2015年 第17卷 第6期   页码 82-85

摘要：

目的：分析和预测生育政策调整对个体及社会带来的各种影响，及时防范这些影响可能导致的各种社会问题。方法：以广州市2 099对“单独二孩”登记夫妻群体为例，分析这一群体人口学等方面的特征。结果：符合“可生育二孩”政策的8万个家庭中受理申请者占26.7 %，有36.5 %的夫妇未确定生育第二胎的时间，35岁以上妇女占妇女总人数的15 %。结论：“单独二孩”政策的实施不会出现“人口暴增”现象，要特别注意高龄产妇生育风险的评估和保障。

关键词： “单独二孩”     群体特征     广州市    

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Choosing configurations of transmission line tower grounding by back flashover probability value

Dmitry KUKLIN

《能源前沿（英文）》 2016年 第10卷 第2期   页码 213-226 doi: 10.1007/s11708-016-0398-6

摘要： There is a considerable number of works devoted to electrical characteristics of grounding. These characteristics are important in general. However, in application to grounding of transmission line towers they are not enough to determine what grounding construction is preferable in some particular case, because these characteristics are calculated or measured apart from the grounded object, and only limited number of current (or voltage) source waveforms is used. This paper indicates reasons in favor of the fact that to choose the optimum design of grounding, the calculation model should include the tower as it is. The probability of back flashover, which provides both qualitative and quantitative estimate of the grounding structure efficiency, can be taken as the criterion for the grounding design. The insulation flashover probability is calculated on the basis of engineering method, which evaluates breakdown strength of insulation for nonstandard waveshapes, and probability data on lightning currents. Different approaches are examined for identifying the back flashover probability, as not only amplitudes but also other parameters can be taken into account. Finite-difference time-domain method is used for calculations of transients. It is found that lightning current waveform can greatly influence calculated back flashover probability value.

关键词： grounding     transmission line tower     back flashover probability     FDTD method    

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Recent transmission of Mycobacterium tuberculosis in China: the implication of molecular epidemiology

null

《医学前沿（英文）》 2018年 第12卷 第1期   页码 76-83 doi: 10.1007/s11684-017-0609-5

摘要：

Tuberculosis (TB) has remained an ongoing concern in China. The national scale-up of the Directly Observed Treatment, Short Course (DOTS) program has accelerated the fight against TB in China. Nevertheless, many challenges still remain, including the spread of drug-resistant strains, high disease burden in rural areas, and enormous rural-to-urban migrations. Whether incident active TB represents recent transmission or endogenous reactivation has helped to prioritize the strategies for TB control. Evidence from molecular epidemiology studies has delineated the recent transmission of ( ) strains in many settings. However, the transmission patterns of TB in most areas of China are still not clear. Studies carried out to date could not capture the real burden of recent transmission of the disease in China because of the retrospective study design, incomplete sampling, and use of low-resolution genotyping methods. We reviewed the implementations of molecular epidemiology of TB in China, the estimated disease burden due to recent transmission of strains, the primary transmission of drug-resistant TB, and the evaluation of a feasible genotyping method of strains in circulation.

关键词： tuberculosis     recent transmission     molecular epidemiology     China    

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Antibiotic resistome mostly relates to bacterial taxonomy along a suburban transmission chain

《环境科学与工程前沿（英文）》 2022年 第16卷 第3期 doi: 10.1007/s11783-021-1466-7

摘要：

• The α-diversities of resistome were lower in manure and compost than in soils.

关键词： Antibiotic resistance genes     Resistome     Bacterial taxonomy     Transmission chain    

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Planet position errors in planetary transmission: Effect on load sharing and transmission error

Miguel IGLESIAS, Alfonso FERNáNDEZ, Ana DE-JUAN, Ramón SANCIBRIáN, Pablo GARCíA

《机械工程前沿（英文）》 2013年 第8卷 第1期   页码 80-87 doi: 10.1007/s11465-013-0362-7

摘要：

In this paper an advanced model of spur gear transmissions developed by the authors is used to study the influence of carrier planet pin hole position errors on the behaviour of the transmission. The model, initially conceived for external gear modeling, has been extended with internal meshing features, and thus increasing its capabilities to include planetary transmission modeling. The new features are presented, along with the summary of the model general approach. The parameters and characteristics of the planetary transmission used in the paper are introduced. The influence of carrier planet pin hole position errors on the planet load sharing is studied, and several static cases are given as examples in order to show the ability of the model. Tangential and radial planet pin hole position errors are considered independently, and the effect of the load level is also taken into account. It is also given attention to the effect on the transmission error of the transmission. Two different configurations for the planetary transmission are used, attending to the fixed or floating condition of the sun, and the differences in terms of load sharing ratio are shown.

关键词： gear     planetary     epicyclic     transmission     load sharing     transmission error    

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An approach for evaluating the impact of an intermittent renewable energy source on transmission expansion

Rongrit CHATTHAWORN,Surachai CHAITUSANEY

《信息与电子工程前沿（英文）》 2015年 第16卷 第10期   页码 871-882 doi: 10.1631/FITEE.1500049

摘要： We propose a new robust optimization approach to evaluate the impact of an intermittent renewable energy source on transmission expansion planning (TEP). The objective function of TEP is composed of the investment cost of the transmission line and the operating cost of conventional generators. A method to select suitable scenarios representing the intermittent renewable energy generation and loads is proposed to obtain robust expansion planning for all possible scenarios. A meta-heuristic algorithm called adaptive tabu search (ATS) is employed in the proposed TEP. ATS iterates between the main problem, which minimizes the investment and operating costs, and the subproblem, which minimizes the cost of power generation from conventional generators and curtailments of renewable energy generation and loads. The subproblem is solved by nonlinear programming (NLP) based on an interior point method. Moreover, the impact of an intermittent renewable energy source on TEP was evaluated by comparing expansion planning with and without consideration of a renewable energy source. The IEEE Reliability Test System 79 (RTS 79) was used for testing the proposed method and evaluating the impact of an intermittent renewable energy source on TEP. The results show that the proposed robust optimization approach provides a more robust solution than other methods and that the impact of an intermittent renewable energy source on TEP should be considered.

关键词： Adaptive tabu search     Renewable energy generation     Robust optimization     Transmission expansion planning    

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Design and characteristic research of a novel electromechanical-hydraulic hybrid actuator with two transmission

《机械工程前沿（英文）》 2023年 第18卷 第2期 doi: 10.1007/s11465-022-0735-x

摘要： Servo-hydraulic actuators (SHAs) are widely used in mechanical equipment to drive heavy-duty mechanisms. However, their energy efficiency is low, and their motion characteristics are inevitably affected by uncertain nonlinearities. Electromechanical actuators (EMAs) possess superior energy efficiency and motion characteristics. However, they cannot easily drive heavy-duty mechanisms because of weak bearing capacity. This study proposes and designs a novel electromechanical-hydraulic hybrid actuator (EMHA) that integrates the advantages of EMA and SHA. EMHA mainly features two transmission mechanisms. The piston of the hydraulic transmission mechanism and the ball screw pair of the electromechanical transmission mechanism are mechanically fixed together through screw bolts, realizing the integration of two types of transmission mechanisms. The control scheme of the electromechanical transmission mechanism is used for motion control, and the hydraulic transmission mechanism is used for power assistance. Then, the mathematical model, structure, and parameter design of the new EMHA are studied. Finally, the EMHA prototype and test platform are manufactured. The test results prove that the EMHA has good working characteristics and high energy efficiency. Compared with the valve-controlled hydraulic cylinder system, EMHA exhibits a velocity tracking error and energy consumption reduced by 49.7% and 54%, respectively, under the same working conditions.

关键词： electromechanical-hydraulic hybrid actuator (EMHA)     integration     transmission mechanisms     power assistance     energy efficiency     working characteristics    

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Aerosol transmission, an indispensable route of COVID-19 spread: case study of a department-store cluster

《环境科学与工程前沿（英文）》 2021年 第15卷 第3期 doi: 10.1007/s11783-021-1386-6

摘要：

• Aerosol transmission is an indispensable route of COVID-19 spread.

关键词： SARS-CoV-2     COVID-19     Environmental factor     Aerosol transmission     Epidemiologic characteristic    

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标题 作者 时间 类型 操作

Eliminating mother-to-child transmission of HBV: progress and challenges in China

Wenzhan Jing, Jue Liu, Min Liu

期刊论文

Current recommendations of managing HBV infection in preconception or pregnancy

null

期刊论文

New medical risks affecting obstetrics after implementation of the two-child policy in China

null

期刊论文

Optimization of the O/HO process with response surface methodology for pretreatment of mother liquor

期刊论文

育龄妇女非意愿妊娠原因分析与对策研究

王代权,刘长艳,向琼,马代慈

期刊论文

Relationship between selenium concentration in child hair and the distribution of Kashin-Beck Disease

LI Shunjiang, YANG Linsheng, WANG Wuyi, LI Yonghua, LI Hairong, XIRAO Ruodeng

期刊论文

儿童乘员约束系统研究现状与展望

方园,吴光强

期刊论文

广州市“单独二孩”登记群体特征分析

唐运革,李飞成,韩立薇

期刊论文

Choosing configurations of transmission line tower grounding by back flashover probability value

Dmitry KUKLIN

期刊论文

Recent transmission of Mycobacterium tuberculosis in China: the implication of molecular epidemiology

null

期刊论文

Antibiotic resistome mostly relates to bacterial taxonomy along a suburban transmission chain

期刊论文

Planet position errors in planetary transmission: Effect on load sharing and transmission error

Miguel IGLESIAS, Alfonso FERNáNDEZ, Ana DE-JUAN, Ramón SANCIBRIáN, Pablo GARCíA

期刊论文

An approach for evaluating the impact of an intermittent renewable energy source on transmission expansion

Rongrit CHATTHAWORN,Surachai CHAITUSANEY

期刊论文

Design and characteristic research of a novel electromechanical-hydraulic hybrid actuator with two transmission

期刊论文

Aerosol transmission, an indispensable route of COVID-19 spread: case study of a department-store cluster

期刊论文