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Seroepidemiology of hepatitis B virus infection and impact of vaccination

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World Journal of Gastroenterology 2015年第25期21卷 7842-7850页

作者： Peng Huang Li-Guo Zhu Ye-Fei Zhu Ming Yue Jing Su Feng-Cai Zhu Hai-Tao Yang Yun Zhang Hong-Bing Shen Rong-Bin Yu xiang-jun zhai Zhi-Hang Peng Department of Epidemiology and Biostatistics School of Public Health Nanjing Medical University Jiangsu Provincial Centre for Disease Control and Prevention Department of Infectious Disease The First Affiliated Hospital of Nanjing Medical University Department of Epidemiology Medical Institute of Nanjing Army

AIM: To investigate hepatitis B virus(HBV) prevalence in the general population in ***: A total of 148931 individuals were investigated by multistage random sampling in Eastern China. Data were collected on demographics and hepatitis B vaccination history, and serum was tested for hepatitis B surface antigen(HBs Ag) by ELISA. RESULTS: A total of 11469 participants(7.70%, 95%CI: 7.57%-7.84%) were positive for HBs Ag. HBs Ag prevalence was 0.77% among children < 5 years old but increased progressively from adolescents(1.40%-2.55%) to adults(5.69%-11.22%). A decrease in HBs Ag prevalence was strongly associated with vaccination and familial history of HBV among both children and adult groups. Meanwhile, HBs Ag risk in adults was associated with invasive testing and sharing needles. The HBV immunization rate among participants aged < 20 years was 93.30%(95%CI: 93.01%-93.58%). Significant difference in HBs Ag prevalence appeared between vaccinated and unvaccinated participants(3.59% vs 10.22%). CONCLUSION: Although the national goal of HBs Ag prevalence < 1% among children < 5 years old has been reached, immunization programs should be maintained to prevent resurgence.

关键词： Epidemiological study Familial history Hepatitis B surface antigen Immunization Generalpopulation

Epidemiology of hepatitis C virus in Iran

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World Journal of Gastroenterology 2015年第38期21卷 10790-10810页

In Iran,the prevalence of hepatitis C virus(HCV) infection is relatively low according to the populationbased epidemiological studies. However,the epidemiology of HCV is changing and the rate of HCV infection is increasing due to the growth in the number of injecting drug users in the society. In addition,a shift has occurred in the distribution pattern of HCV genotypes among HCV-infected patients in Iran. Genotype 1a is the most prevalent genotype in Iran,but in recent years,an increase in the frequency of 3a and a decrease in 1a and 1b have been reported. These variations in the epidemiology of HCV reflect differences in the routes of transmission,status of public health,lifestyles,and risk factors in different groups and geographic regions of Iran. Health policy makers should consider these differences to establish better strategies for control and prevention of HCV infection. Therefore,this review was conducted to present a clear view regarding the current epidemiology of HCV infection in Iran.

关键词： Hepatitis C virus Blood donors Injecting drug user

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河北农村≤5岁留守儿童生长发育状况分析

中国公共卫生 2017年第3期33卷 482-485页

作者：郭建花阎香娟翟俊霞刘斯文石家庄市疾病预防控制中心河北050011 河北省医学情报所

目的评估河北省农村地区≤5岁留守儿童身高与体重生长发育状况,为促进留守儿童健康成长提供依据。方法 2014年10月从全国第五次卫生服务调查家庭健康询问调查河北省数据库提取1 022名≤5岁农村儿童信息,分析留守儿童与非留守儿童年龄别... 详细信息

目的评估河北省农村地区≤5岁留守儿童身高与体重生长发育状况,为促进留守儿童健康成长提供依据。方法 2014年10月从全国第五次卫生服务调查家庭健康询问调查河北省数据库提取1 022名≤5岁农村儿童信息,分析留守儿童与非留守儿童年龄别身高得分(HAZ)与其生长发育状况构成、年龄别体重得分(WAZ)与其体重情况构成。结果河北省农村地区≤5岁留守儿童270人(26.42%),平均年龄2.67岁,男女性别比为1.16:1。父亲单独外出务工儿童198人(73.33%),184名(68.15%)监护人为留守母亲。留守儿童的平均HAZ、WAZ分别为-3.71、-1.07分,均低于相应非留守儿童的0.14、2.25分(t_(HAZ)=19.21,P_(HAZ)=0.000;t_(WAZ)=8.96,P_(WAZ)=0.000)。留守儿童中,生长发育迟缓构成比、体重不足构成比分别为78.15%、53.33%,均高于非留守儿童的18.88%、9.04%(χ_(生长)~2=374.90,P_(生长)=0.000;χ_(体重)~2=262.01,P_(体重)=0.000)。分层分析后,无论性别与年龄,留守儿童HAZ、WAZ均低于非留守儿童,生长发育迟缓构成比与体重不足构成比均高于非留守儿童(P<0.05)。结论河北省农村≤5岁留守儿童成长状况不容乐观,需引起重点关注。

关键词：农村地区 ≤5岁儿童留守儿童身高体重

Effect of casting speed on dendrite arm spacing of Mn13 steel continuous casting slab

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Journal of Iron and Steel Research International 2020年第6期27卷 665-672页

作者： Jian-min Li Mao-fa Jiang jun-xiang Ning jun zhai Key Laboratory for Ecological Metallurgy of Multimetallic Ores(Ministry of Education) Northeastern UniversityShenyang110819LiaoningChina Shanxi Taigang Stainless Steel Co. Ltd.Taiyuan 030003ShanxiChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina

The dendrite arm spacing in the continuous casting slab of Mn13 steel under different casting speeds was measured using the metallographic microscope. Meanwhile, a heat transfer model was established by the Pro-cast software. The relationship between the dendrite arm spacing and casting speed in continuous casting slab of Mn13 steel was studied and described by a function expression. The results provide an important theoretical basis for the development and optimization of con-tinuous casting production process of high-manganese steel and help to improve the quality of continuous casting slab of high-manganese steel. Under the experimental conditions, the suitable casting speed is about 0.9 m/min. The secondary dendrite spacing maintains a relatively stable low-amplitude increase trend, and it is beneficial to obtain a higher proportion of equiaxed crystals.

关键词： High-manganese steel Dendrite arm spacing Continuous casting Casting speed

Latest Data Constraint of Some Parameterized Dark Energy Models

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Chinese Physics Letters 2023年第1期40卷 76-84页

作者： Jing Yang Xin-Yan Fan Chao-jun Feng xiang-Hua zhai Division of Mathematica and Theoretical Physics Shanghai Normal UniversityShanghai 200234China

Using various latest cosmological datasets including type-Ia supernovae, cosmic microwave background radiation, baryon acoustic oscillations, and estimations of the Hubble parameter, we test some dark-energy models with parameterized equations of state and try to distinguish or select observation-preferred models. We obtain the best fitting results of the six models and calculate their values of the Akaike information criteria and Bayes information criterion. We can distinguish these dark energy models from each other by using these two information criterions. However, the ΛCDM model remains the best fit model. Furthermore, we perform geometric diagnostics including statefinder and Om diagnostics to understand the geometric behavior of the dark energy models. We find that the six dark-energy models can be distinguished from each other and from ΛCDM, Chaplygin gas, quintessence models after the statefinder and Om diagnostics are performed. Finally, we consider the growth factor of the dark-energy models with comparison to the ΛCDM model. Still, we find the models can be distinguished from each other and from the ΛCDM model through the growth factor approximation.

关键词： criterion cosmic geometric

Customisable sound absorption properties of functionally graded metallic foams

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Journal of Materials Science & Technology 2022年第13期108卷 196-207页

作者： jun Wei Chua Xinwei Li Tao Li Beng Wah Chua xiang Yu Wei zhai Department of Mechanical Engineering National University of Singapore117575Singapore Agency for Science Technology and Research(A^(*)STAR)Singapore Institute of Manufacturing Technology138634Singapore Agency for Science Technology and Research(A^(*)STAR)Engineering MechanicsInstitute of High-Performance Computing1 Fusionopolis Way138632Singapore

In this study,functionally graded foam made of Inconel 625 superalloy was successfully produced using the template replication method,with open-cell polyurethane foams as a *** products have a similar pore morphology as the templates and adjacent layers were successfully sintered together by particle *** absorption experiments on graded metallic foams reveal that the sound absorption at particular frequency ranges can be improved by various permutations of foam *** graded foam of two distinct pore sizes,a mathematical equation was proposed to predict the location of the intersection point of the sound absorption curves,thereby aiding in graded foam *** increase in sound absorption coefficients by resonance-like effects can be introduced before the intersection points by placing the foam layer of smaller pore size nearer to the sound *** sound absorption performances can be further customized when the thickness proportion of the pore sizes is changed and when the number of distinct pore sizes used is *** sound absorption performance at lower frequencies is generally boosted by resonance-like effects when the layer of foam with the largest pore size is placed furthest from the sound *** the same composition of foam with a fixed thickness proportion of pore sizes,one can introduce resonance-like effects to improve the sound absorption performance compared to other permutations while possibly satisfying weight requirements in practical *** study provides valuable insights and mathematical guidelines in the design and manufacturing of functionally graded metallic foam for specific applications.

关键词： Template replication method Functionally graded foam Sound absorption Transfer matrix method Composite metal foam

INVERSION OF TRACE FORMULAS FOR A STURM-LIOUVILLE OPERATOR

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Journal of Computational Mathematics 2022年第3期40卷 396-414页

作者： xiang Xu Jian zhai School of Mathematical Sciences Zhejiang UniversityHangzhouChina Institute for Advanced Study The Hong Kong University of Science and TechnologyHong KongChina

This paper revisits the classical problem“Can we hear the density of a string?”,which can be formulated as an inverse spectral problem for a Sturm-Liouville *** of inverting the map from density to spectral data directly,we propose a novel method to reconstruct the density based on inverting a sequence of trace formulas which bridge the density and its spectral data clearly in terms of a series of nonlinear integral *** experiments are presented to verify the validity and effectiveness of the proposed numerical *** impact of different parameters involved in the algorithm is also discussed.

关键词： Inverse spectral problem Sturm-Liouville operator Trace formulas

Multi-pole dark energy

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Chinese Physics C 2020年第10期44卷 169-177页

作者： Chao-jun Feng xiang-Hua zhai Xin-Zhou Li Division of Mathematical and Theoretical Physics Shanghai Normal UniversityShanghai 200234China Center for Astrophysics Shanghai Normal UniversityShanghai 200234China

A scalar field with a pole in its kinetic term is often used to study cosmological inflation;it can also play the role of dark energy,which is called the pole dark energy *** propose a generalized model where the scalar field may have two or even multiple poles in the kinetic term,and we call it the multi-pole dark *** find that the poles can place some restrictions on the values of the original scalar field with a non-canonical kinetic *** the transformation to the canonical form,we get a flat potential for the transformed scalar field even if the original field has a steep *** late-time evolution of the universe is obtained explicitly for the two pole model,while dynamical analysis is performed for the multiple pole *** find that it does have a stable attractor solution,which corresponds to the universe dominated by the potential of the scalar field.

关键词： dark energy scalar field cosmology

Mechanism and application of an online intelligent evaluation model for energy consumption of a reheating furnace

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Journal of Iron and Steel Research International 2023年第1期30卷 102-111页

作者： xiang-jun Bao Jing Xu Guang Chen Xu Chen Hong-guang Zhang Yi-ming Shen Wei zhai Department of Thermal Energy School of Energy and EnvironmentAnhui University of TechnologyMa’anshan 243002AnhuiChina Department of Metallurgical Engineering School of Energy and EnvironmentAnhui University of TechnologyMa’anshan 243002AuhuiChina Department of Construction and Environmental Engineering School of Architectural EngineeringAnhui University of TechnologyMa’anshan 243002AnhuiChina Ma’anshan Iron and Steel Co. Ltd.Ma’anshan 243003AnhuiChina

An online model was proposed to identify the reasons behind changes in the energy consumption of the reheating furnace of a steel processing *** heat conversion of the furnace was analyzed and integrated with the fuel consumption of the furnace to obtain a model of the energy *** with the mechanism analysis,the basic parameters affecting energy consumption were determined,and four key influencing factors were obtained:furnace output,furnace charging temperature,furnace tapping temperature,and steel *** specific calculation method of the contribution of each influencing factor was derived to define the conditions of the baseline energy consumption,while the online data were used to calculate the energy value and the actual performance value of the baseline energy *** contribution of each influencing factor was determined through *** cloud platform was used for database reconstruction and programming to realize the online intelligent evaluation of the energy consumption of the reheating ***,a case study of the evaluation of the practical energy consumption of a steel rolling furnace in a steel plant was *** intelligent evaluation results were quantified and displayed online,and the performance of the system in reducing production line energy consumption was demonstrated.

关键词： Online intelligent evaluation Model mechanism Contribution Data reconstruction