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Biomedical and Environmental Sciences 2019年第1期32卷 51-57页

作者： LIN Hong LUO mi Yang LUO Jia You zeng Rong LI Ya Mei DU Qi Yun FANg Jun Qun Xiangya School of Public Health Central South University Saw Swee Hock School of Public Health National University of Singapore Xiangya Hospital of Central South University Hunan Provincial Maternal and Child Health Care Hospital

Worldwide, the incidence of birth defects in low-income countries is 6.42%, while in middle-income and high-income countries it is 5.57% and 4.72%, respectively;approximately 303, 000 newborns die from birth defects each year. In China, the incidence of birth defects is about 5.6%, and around 8.14 million people have congenital disabilities, accounting for 9.6% of total disabled people[1]. Birth defect remains a major clinical and public health challenge because of its high fatality rate and protracted and severe sequela.

关键词： Birth defects demographics Environmental risk factors

Antenna Decoupling Based on Characteristic Modes Cancellation

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Chinese Journal of Electronics 2022年第6期31卷 1138-1145页

作者： CHU Qingxin zeng Wenfeng School of Electronic and Information Engineering South China University of Technology

The demand for a high transmission data rate in 5g leads to the wide application of the multi-input, multi-output(miMO) technique. However, the narrow design space in mobile phone causes severe unexpected coupling between antenna units and deteriorate the system performance dramatically. In this paper, we focus on the antenna coupling within the miMO system. Some decoupling techniques are summarized, such as neutralization line, decoupling network, common/differential mode cancellation, etc. Finally, new decoupling research developments of modal currents cancellation based on the theory of characteristic mode are elaborated. Two design examples are shown to validate the benefit of the proposed decoupling method. The-6 dB impedance bandwidth of the head-to-head antenna pair can cover 3.4–3.6 *** isolation level is improved from more than 3.7 dB to more than 13 dB. The tail-to-tail antenna pair can cover 3.3–5 gHz and the isolation level is improved from more than 5 dB to more than 10 dB in the whole operating bandwidth. Both antenna pairs can achieve an envelop correlation coefficient of less than 0.2 and the antenna efficiencies are more than 40%.

关键词： neutralization line severe unexpected coupling mobile phone antenna pairs 3.3-5 gHz antenna units antenna radiation patterns narrow design space high transmission data rate mobile handsets multiinput miMO system multioutput technique 5g mobile communication characteristic mode decoupling method 6 dB impedance bandwidth antenna efficiencies antenna coupling miMO communication system performance antenna decoupling modal currents cancellation characteristic modes cancellation isolation level tail-to-tail antenna pair head-to-head antenna pair decoupling research developments decoupling techniques

产教融合背景下工业视觉现场工程师人才培养体系研究

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船舶职业教育 2025年第1期13卷 1-4页

作者：曾鹏易杰湖南工业职业技术学院湖南长沙410208

现场工程师专项培养计划是职业教育领域实现紧缺技术技能人才培育的重要举措。为加快培养高素质技术技能的创新型人才,围绕人才培养目标与标准,通过深入剖析现场工程师内涵价值,探索研究构建产教融合背景下现场工程师人才培养课程体系,... 详细信息

现场工程师专项培养计划是职业教育领域实现紧缺技术技能人才培育的重要举措。为加快培养高素质技术技能的创新型人才,围绕人才培养目标与标准,通过深入剖析现场工程师内涵价值,探索研究构建产教融合背景下现场工程师人才培养课程体系,以期为建立先进装备制造工业视觉现场工程师典型培养模式提供理论支撑。

关键词：现代学徒制现场工程师产教融合人才培养

Effect of Heat Treatment Time on Dy–Cu Alloy Diffusion Process in Dy-Containing Commercial Nd–Fe–B Sintered Magnets

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Acta Metallurgica Sinica(English Letters) 2018年第5期31卷 496-502页

作者： H.Y.Liu g.Wang Y.Hong D.C.zeng School of Materials Science and Engineering South China University of Technology

In this paper, the grain boundary diffusion process（gBDP） using a Dy70Cu30（at.%） alloy as the diffusion source was performed in a commercial sintered Nd–Fe–B magnet, and the effect of heat treatment time on the microstructure and magnetic properties of the magnet was investigated in detail. For the processed magnets heat-treated at 860℃, as heat treatment time increased, the coercivity and the depth of（Nd,Dy）2Fe14B core–shell structure increased first and then decreased. However, when the heat treatment time was more than 2 h, the diffusion path of Dy from the Dy-rich shell phase into the Nd2Fe14B grains was revealed, and a nearly homogeneous（Nd,Dy）2Fe14B phase was formed, which brought on the decrease in both the depth of visible core–shell structure and the coercivity of Nd–Fe–B magnet.

关键词： Sintered Nd-Fe-B magnets grain boundary diffusion Heat treatment time Coercivity micromagnetic simulation

牡蛎壳改性蓝藻生物炭对水中四环素的吸附性能

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福建农林大学学报(自然科学版) 2025年第02期54卷 238-249页

作者：梁耐思曾悦陈小丽李进广东海洋大学化学与环境学院

【目的】通过制备牡蛎壳改性蓝藻生物炭（oyster shell-modified cyanobacterial biochar, CaBC）去除水体中的四环素（tetracycline, TC）,探讨CaBC在水中的吸附性能，为水体抗生素污染治理提供依据。【方法】以蓝藻为原料，使用400℃... 详细信息

【目的】通过制备牡蛎壳改性蓝藻生物炭（oyster shell-modified cyanobacterial biochar, CaBC）去除水体中的四环素（tetracycline, TC）,探讨CaBC在水中的吸附性能，为水体抗生素污染治理提供依据。【方法】以蓝藻为原料，使用400℃煅烧的牡蛎壳作为钙源，通过水热合成法制备CaBC,用于去除水溶液中的TC。利用扫描电子显微镜、傅里叶变换红外光谱（FTIR）、X射线衍射（FTIR）及比表面积测定法对改性前后的生物炭进行表征分析。【结果】CaBC具有明显增多的表面官能团、更大的比表面积和孔体积及更小的粒径。FTIR和XRD表征结果表明，生物炭（biochar, BC）成功负载了牡蛎壳。与BC相比，CaBC去除率提高了22.8%。在TC初始质量浓度为80 mg·L-1、CaBC投加量为1.25 g·L-1、pH=9.0的条件下，CaBC对TC的去除率达到87.15%。Langmuir模型拟合结果表明，随着TC初始溶液浓度的增加，CaBC的吸附能力增强。动力学试验表明，CaBC对TC的吸附行为符合准二级动力学模型，表明吸附过程为单分子层的化学吸附。研究表明，CaBC通过孔隙填充、π-π相互作用及静电引力实现对TC的高效吸附。经过5次吸附—解吸循环后，去除率仍保持在51.83%,证明其具有较高的吸附效率和稳定性。【结论】CaBC在去除水体中的TC方面表现出优异的吸附性能，其高效性和稳定性显示了其在TC污染水体中的广阔应用前景。

关键词：蓝藻生物炭牡蛎壳吸附四环素

瓜蒌- 薤白调节肠道菌群治疗冠心病模型大鼠的作用及机制

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中国组织工程研究 2025年第5期29卷 917-927页

作者：孙广瀚谢珍聪孙咪徐洋郭栋山东中医药大学第一临床医学院山东省济南市250014 山东中医药大学教师发展中心山东省济南市250355 山东中医药大学药物研究院山东省济南市250355

背景:基于网络药理学方法发现瓜蒌-薤白药对中主要生物活性化合物对冠心病有多功能作用;然而其治疗冠心病的机制尚未得到充分阐释。目的:探讨瓜蒌-薤白通过调节肠道微生物的组成改善冠心病的作用及机制。方法:40只SD大鼠按随机数字表法... 详细信息

背景:基于网络药理学方法发现瓜蒌-薤白药对中主要生物活性化合物对冠心病有多功能作用;然而其治疗冠心病的机制尚未得到充分阐释。目的:探讨瓜蒌-薤白通过调节肠道微生物的组成改善冠心病的作用及机制。方法:40只SD大鼠按随机数字表法分为空白组、模型组、阳性药组、药对组,除空白组外,其余大鼠连续灌胃脂肪乳剂和注射垂体后叶素制备冠心病大鼠模型。造模后模型组大鼠灌胃蒸馏水(10 mL/kg)进行对照,阳性药组大鼠每日灌胃辛伐他汀4 mg/kg,药对组每日灌胃瓜蒌-薤白7.56 g/kg,各组大鼠给药均为14 d。观察大鼠心电图、心肌病理及血脂变化,并通过16S rDNA测序技术研究大鼠经干预后肠道微生物结构。结果与结论:①心电图结果显示模型组ST抬高;阳性药组与药对组心电图无明显问题。②与空白组相比,模型组总胆固醇、三酰甘油、低密度脂蛋白胆固醇水平均显著增高(P0.05),Simpson指数降低(Pgenes_group_norank等相对丰度降低;与模型组相比,药对组WPS-2_norank、Muribaculaceae_norank等相对丰度升高,Clostridia、[Eubacterium]_coprostanoligenes_group_norank等相对丰度降低;阳性药组Desulfobacterota、[Eubacterium]_coprostanoligenes_group_norank等相对丰度升高,Firmicutes、Muribaculaceae_norank等相对丰度降低;与阳性药相比,药对组Desulfobacterota、Bacteroides等相对丰度升高,Firmicutes、[Eubacterium]_coprostanoligenes_group_norank等相对丰度降低;LEfSe结果发现差异显著的种群富集于药对组最多,其次是空白组、阳性药组,模型组最少。⑥结论:瓜蒌-薤白可以通过调节肠道菌群改善冠心病的发生发展,为进一步研发瓜蒌-薤白提供新的启示。

关键词： “瓜蒌-薤白”药对 16S rDNA 冠心病肠道菌群大鼠

Species diversity and population density affect genetic structure and gene dispersal in a subtropical understory shrub

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Journal of Plant Ecology 2012年第3期5卷 270-278页

作者： Xueqin zeng Stefan g.michalski Markus Fischer Walter Durka UFZ-Helmholtz Centre for Environmental Research Department of Community Ecology(BZF)Theodor-Lieser-Strasse 4D-06120 HalleGermany Institute of Plant Sciences University of BernAltenbergrain 21CH-3013 BernSwitzerland

Aims The dispersal of pollen and seeds is spatially restricted and may vary among plant populations because of varying biotic interactions,population histories or abiotic *** gene dispersal is spatially restricted,it will eventually result in the development of spatial genetic structure(SgS),which in turn can allow insights into gene dispersal ***,we assessed the effect of habitat characteristics like population density and community structure on small-scale SgS and estimate historical gene dispersal at different spatial *** In a set of 12 populations of the subtropical understory shrub Ardisia crenata,we assessed genetic variation at 7 microsatellite loci within and among *** investigated small-scale genetic structure with spatial genetic autocorrelation statistics and heterogeneity tests and estimated gene dispersal distances based on population differentiation and on within-population *** was related to habitat characteristics by multiple *** Findings The populations showed high genetic diversity(He=0.64)within populations and rather strong genetic differentiation(F#ST=0.208)among populations,following an isolation-by-distance pattern,which suggests that populations are in gene flow–drift *** SgS was present within populations(mean Sp=0.027).Population density and species diversity had a joint effect on SgS with low population density and high species diversity leading to stronger small-scale *** of historical gene dispersal from between-population differentiation and from within-population SgS resulted in similar values between 4.8 and 22.9 *** results indicate that local-ranged pollen dispersal and inefficient long-distance seed dispersal,both affected by population density and species diversity,contributed to the genetic population structure of the *** suggest that SgS in shrubs is more similar to that of herbs than to trees and that in communities with

关键词： Ardisia crenata BEF China gene flow habitat effects spatial genetic structure

Synthesis of Cell Adhesive Motif RgD Tripeptide by a Novel Chemical Method and Its Purification

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Chemical Research in Chinese Universities 2006年第5期22卷 612-616页

作者： WANg Hua ZHAO mi-feng MA Cheng-yun JINg Wei HUANg Yi-bing HOU Rui-zhen zeng Hong-bin XU Li ZHANg Xue-zhong Key Laboratory of Molecular Enzymology and Engineering Jilin University Changchun 130021 P. R. China China-Japan Union Hospital of Jilin University Changchun 130033 P. R. China First Hospital of Jilin University Changchun 130021 P. R. China

The cell adhesive motif RgD tripeptide was synthesized by using a novel chemical method. First, gly-Asp（gD） was synthesized in two steps including the chloroacetylation of free L-aspartic acid and the ammonolysis of the chloroacetylated L-aspartic acid. The yield of chloroacetylated L-aspartic acid was 83.0%. For the ammonolysis of chloroacetylated L-aspartic acid, the yield of the ammonolyzed product was 92. 3%. Second, the coupling between Arg and gly-Asp was carried out by using the NCA method. The maximum yield of RgD was about 50% at 0℃ and pH = 9. 5. The prepared RgD tripeptide was confirmed by using amino acid component analysis and mass spectrographic analysis.

关键词： RgD tripeptide Chemical synthesis Purification Arg-gly-Asp

Phylogenetic diversity of dimethylsulfoniopropionate-dependent demethylase gene dmdA in distantly related bacteria isolated from Arctic and Antarctic marine environments

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Acta Oceanologica Sinica 2019年第8期38卷 64-71页

作者： Yinxin zeng Key Laboratory for Polar Science of State Oceanic Administration Polar Research Institute of China

Dimethylsulfoniopropionate(DMSP) is mainly produced by marine phytoplankton as an osmolyte, antioxidant,predator deterrent, or cryoprotectant. DMSP is also an important carbon and sulfur source for marine *** may metabolize DMSP via the demethylation pathway involving the DMSP demethylase gene(dmdA) or the cleavage pathway involving several different DMSP lyase genes. Most DMSP released into seawater is degraded by bacteria via demethylation. To test a hypothesis that the high gene frequency of dmdA among major marine taxa results in part from horizontal gene transfer(HgT) events, a total of thirty-one bacterial strains were isolated from Arctic Kongsfjorden seawater in this study. Analysis of 16S rRNA gene sequences showed that,except for strains BSw22118, BSw22131 and BSw22132 belonging to the genera Colwellia, Pseudomonas and glaciecola, respectively, all bacteria fell into the genus Pseudoalteromonas. DmdA genes were detected in five distantly related bacterial strains, including four Arctic strains(Pseudoalteromonas sp. BSw22112, Colwellia ***22118, Pseudomonas sp. BSw22131 and glaciecola sp. BSw22132) and one Antarctic strain(Roseicitreum antarcticum ZS2–28). Their dmdA genes showed significant similarities(97.7%–98.3%) to that of Ruegeria pomeroyi DSS–3, which was originally isolated from temperate coastal seawater. In addition, the sequence of the gene transfer agent(gTA) capsid protein gene(g5) detected in Antarctic strain ZS2–28 exhibited a genetically closely related to that of Ruegeria pomeroyi DSS–3. Among the five tested strains, only Pseudomonas sp. BSw22131 could grow using DMSP as the sole carbon source. The results of this study support the hypothesis of HgT for dmdA among taxonomically heterogeneous bacterioplankton, and suggest a wide distribution of functional gene(i.e., dmdA) in global marine environments.

关键词： dimethylsulfoniopropionate-dependent demethylase gene(dmdA) horizontal gene transfer marine bacteria Arctic Antarctic

On grain refinement and titanium segregation in Al-Si alloy

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China Foundry 2007年第4期4卷 273-275页

作者： mi.guo-fa WANg Kuang-fei WEN Tao ZHANg mi.g WANg Hong-wei zeng Song-yan School of Materials Science and Engineering Henan Polytechnic University Jiaozuo 454000 China School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

The influence of holding time and distance from sample bottom on segregation and grain refinement of Ti was studied. Results show that Al-STi-IB has an obvious effect on refinement in AI-Si alloy after 4 h holding time. The segregation of Ti shows different morphology at different positions of casting. More segregation is at the bottom of castings because of localized congregation of Ti. The research shows that the difference in Ti concentration is as high as 25.6% between the top and bottom of castings.

关键词： aluminum-silicon alloy Ti segregation grain refinement