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Epigenetics and environmental health

Frontiers of Medicine 2024年第4期18卷 571-596页

作者： Min Zhang Ting Hu tianyu ma Wei Huang Yan Wang Key Laboratory of Cancer and Microbiome State Key Laboratory of Molecular OncologyNational Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing100021China Beijing Key Laboratory of Cancer Invasion and Metastasis Research Department of Biochemistry and Molecular BiologySchool of Basic Medical SciencesCapital Medical UniversityBeijing100069China

Epigenetic modifications including DNA methylation,histone modifications,chromatin remodeling,and RNA modifications complicate gene regulation and heredity and profoundly impact various physiological and pathological *** recent years,accumulating evidence indicates that epigenetics is vulnerable to environmental changes and regulates the growth,development,and diseases of individuals by affecting chromatin activity and regulating gene *** exposure or induced epigenetic changes can regulate the state of development and lead to developmental disorders,aging,cardiovascular disease,Alzheimer's disease,cancers,and so ***,epigenetic modifications are *** use of specific epigenetic inhibitors targeting epigenetic changes in response to environmental exposure is useful in disease ***,we provide an overview of the role of epigenetics in various ***,we summarize the mechanism of epigenetic alterations induced by different environmental exposures,the influence of different environmental exposures,and the crosstalk between environmental variation epigenetics,and genes that are implicated in the body's ***,the interaction of multiple factors and epigenetics in regulating the initiation and progression of various diseases complicates clinical *** discuss some commonly used epigenetic drugs targeting epigenetic modifications and methods to prevent or relieve various diseases regulated by environmental exposure and epigenetics through diet.

关键词： epigenetics environmental exposure health prevention and therapy

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Discovering Changes in the Global Liquefied Natural Gas marine Supply Network During the Russian-Ukrainian Crisis with Big Data

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Chinese Geographical Science 2024年

作者： XIAO Renrong ZHAO Pengjun ZHANG Mengzhu KANG Tingting ma tianyu College of Resources and Environment Lanzhou University Key Laboratory of Earth Surface System and Human-Earth Relations Ministry of Natural Resources of China School of Urban Planning and Design Peking University

The recent Russian-Ukrainian crisis has had a substantial impact on the global natural gas supply landscape and brought major challenges to liquified natural gas(LNG) supply chain safety in many countries. However, academic research in this field remains scarce. This study aims to analyze the global LNG marine supply network changes during the recent Russian-Ukrainian crisis. Big data analytics are applied to the global vessel trajectory information recorded by automatic identification system(AIS). The weighted degree index indicates that global LNG marine supply is still primarily led by a few exporting countries, and the Middle East Port of Ras Laffan now occupies the central position. In 2022, the betweenness centrality and other indicators of the LNG shipping network showed a high middle and low end, indicating that the network has a certain degree of resilience. After the Russian-Ukrainian crisis happened,LNG exports from Qatar, the United States, and Russia increased. Resource flows have reshaped the competitive standing of *** European LNG market witnessed a significant intensification in the export competition between Russia and the United States. Despite the ongoing crisis, Russia's LNG export competitiveness remained resilient and displayed no indications of weakening. The results show new evidence for the changes in global natural resources marine supply influenced by the geopolitical events among *** has important implications for policymaking of LNG supply safety to the countries that rely heavily on imports.

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Shortened processing duration of high-performance Sm-Co-Fe-Cu-Zr magnets by stress-aging

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Journal of materials Science & Technology 2022年第11期106卷 70-76页

作者： Xianglong Zhou Tao Yuan tianyu ma Frontier Institute of Science and Technology State Key Laboratory for Mechanical Behavior of Materialsand MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed MatterXi’an Jiaotong UniversityXi’an 710049China The Southwest Applied magnetism Research Institute Mianyang 621000China

Simultaneously achieving high energy product and high coercivity in the 2:17-type Sm-Co-Fe-Cu-Zr high temperature magnets has been closely relied on long-term isothermal aging to develop complete cellu-lar *** this work,we report a novel stress-aging approach that can substantially shorten the aging time to fabricate high-performance Sm-Co-Fe-Cu-Zr *** exhibited by a model magnet Sm_(25) Co_(50.2) Fe_(16.2) Cu_(5.6) Zr_(3.0)(wt.%),applying 90 MPa compressive stress can shorten the aging time from 20 h for conventional isothermal aging to 10 h at the same aging temperature for achieving nearly equiv-alent magnetic *** comparative study between the 10 h-aged samples under stress-containing and stress-free conditions revealed that the stress not only promotes the precipitation of the cell boundary phase that are essential for enhancing the coercivity but also accelerates the dissociation of the cell edge defects that are detrimental to squareness factor,without destroying the[001]crystal-lographic *** microstructural improvements enable the achievement of high-performance with maximum energy product of∼30 MGOe and coercivity above 35 kOe at reduced aging time.

关键词： Permanent magnets Sm-Co magnets Precipitation Stress-aging

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面向舰船目标检测的SAR图像数据PCGAN生成方法

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西南交通大学学报 2024年第3期59卷 547-555页

作者：潘磊郭宇诗李恒超王伟业李泽琛马天宇中国电子科技集团公司第十研究所四川成都610036 西南交通大学计算机与人工智能学院四川成都611756 西南交通大学信息科学与技术学院四川成都611756 西南交通大学综合交通大数据应用技术国家工程实验室四川成都611756

针对现有合成孔径雷达(SAR)图像数据生成方法大多无法同时生成舰船图像及其检测标签的问题,面向SAR舰船图像生成及目标检测任务,构建基于位置信息的条件生成对抗网络(PCGAN).首先,提出将舰船位置信息作为约束条件用于限制生成图像中舰... 详细信息

针对现有合成孔径雷达(SAR)图像数据生成方法大多无法同时生成舰船图像及其检测标签的问题,面向SAR舰船图像生成及目标检测任务,构建基于位置信息的条件生成对抗网络(PCGAN).首先,提出将舰船位置信息作为约束条件用于限制生成图像中舰船的位置,并将其作为舰船图像的检测标签;随后,引入Wasserstein距离稳定PCGAN的训练过程;最后,利用生成的SAR舰船图像及对应检测标签完成YOLOv3网络的端到端训练,实现舰船数据增强与目标检测的协同学习,进而获得更耦合目标检测实际应用的多样性数据.在HRSID(high resolution SAR image dataset)数据集上的实验结果表明,PCGAN方法能生成清晰、鲁棒的SAR舰船数据,舰船检测准确度最高提升1.01%,验证了所提出方法的有效性.

关键词：合成孔径雷达生成对抗网络数据增强舰船检测位置信息

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Formation mechanism of partial stacking faults by incompletemixed-mode phase transformation: A case study of Fe-Ga alloys

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Journal of materials Science & Technology 2022年第22期117卷 59-64页

作者： Tianzi Yang tianyu ma Feng Liu Xiaobing Ren Frontier Institute of Science and Technology State Key Laboratory for Mechanical Behavior of Materialsand MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed MatterXi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of Solidification Processing and Analytical and Testing Center Northwestern Polytechnical UniversityXi’an 710072China Center for Functional materials National Institute for Materials ScienceTsukuba 305-0047IbarakiJapan

Partial stacking faults(PSFs) formed by incomplete mixed-mode phase transformation have been found to exhibit unfixed slip distance of closely-packed planes unlike those of the deformation-induced stacking faults(SFs) with fixed distance. Though engineering PSFs can yield appealing properties, such as the enhanced damping capacity, understanding of the interaction between lattice distortion and atomic diffusion and their influences on forming PSFs is still far from being clear. Herein we performed a case study on aged Fe-Ga alloy that undergoes a mixed-mode phase transformation from body-centered cubic(BCC)to ordered face-centered cubic(FCC). The TEM investigations showed that the faulted {111}-FCC distance of the PSFs is shorter than a/6 of the typical {111}- SFs in deformed FCC materials and the PSFs have disordered Fe and Ga arrangements. Further studies revealed that such PSFs will not be completely dissociated at FCC twin boundaries(TBs) even after long term isothermal aging. Consequently,the formation of PSFs can be ascribed to the transformation-dependent atomic ordering and lattice shear strain of the parent BCC lattice, where the diffusion-controlled glides of the PSFs-associated dislocations will accelerate atomic diffusions due to the dislocation-pipe effect along -FCC direction, but may hinder the atomic diffusions across the {111}-FCC TBs due to the retarding effect. This study may add important insight into the defects process during mixed-mode phase transformation and broaden the knowledge of the interaction between concurrently-happened lattice distortion and atomic diffusion.

关键词： Stacking faults Mixed-mode phase transformation Diffusion Lattice distortion Fe-Ga alloy

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驼峰车辆减速器制动性能影响因素分析

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铁道通信信号 2024年第6期60卷 35-41页

作者：屠志平马天宇安岩中国铁道科学研究院集团有限公司通信信号研究所北京100081

驼峰作业过程中,溜放车辆经减速器制动后容易出现超速、夹停、轻车挤出等制动问题。通过理论分析和实验方法,分析制动高度、制动宽度、轮辋外径变化、摩擦系数等因素对减速器制动性能的影响情况。结果表明:提高摩擦系数和制动高度、增... 详细信息

驼峰作业过程中,溜放车辆经减速器制动后容易出现超速、夹停、轻车挤出等制动问题。通过理论分析和实验方法,分析制动高度、制动宽度、轮辋外径变化、摩擦系数等因素对减速器制动性能的影响情况。结果表明:提高摩擦系数和制动高度、增大杠杆比、减少制动宽度等,能有效降低减速器超速的发生概率;提高制动高度、减少附加制动力系数、提高制动轨强度、降低摩擦系数等,能有效降低轻车挤出的发生概率;提高传动系统动力、减少零部件摩擦阻力、增大曲拐偏心等,能有效避免夹停问题的发生。由此提出解决减速器制动问题的措施和建议,为减速器设计、安装施工、维修维护等,提供理论支持和设计依据。

关键词：驼峰车辆减速器制动性能轻车挤出超速夹停

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芸豆GH3基因家族鉴定及进化与表达分析

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西北植物学报 2024年第9期44卷 1433-1444页

作者：张晓旭马媛媛罗新锐秦耀新马天宇王玉萍甘肃农业大学园艺学院兰州730070

【目的】探究芸豆中PvGH3家族成员的特征及在非生物胁迫响应中的作用,为深入研究其基因功能提供参考依据,也为芸豆抗逆新品种的选育提供新的基因资源。【方法】通过生物信息学的方法对芸豆GH3基因家族进行全基因组鉴定,用荧光定量PCR(qR... 详细信息

【目的】探究芸豆中PvGH3家族成员的特征及在非生物胁迫响应中的作用,为深入研究其基因功能提供参考依据,也为芸豆抗逆新品种的选育提供新的基因资源。【方法】通过生物信息学的方法对芸豆GH3基因家族进行全基因组鉴定,用荧光定量PCR(qRT-PCR)检测PvGH3基因在不同逆境胁迫下的表达。【结果】在芸豆中鉴定出19个PvGH3基因,其中17个基因不均匀分布于8条染色体上,其余2个基因定位于scafford上无法精确定位;可分为3个亚族,各亚族间的成员有相似的基因结构和保守基序;各成员间存在3个旁系同源基因对,与拟南芥GH3间有15个直系同源基因对;含有光、激素、胁迫及生长发育相关顺式元件;19个PvGH3在响应干旱(6%PEG)、盐(100 mmol/L NaCl溶液)和低温(4℃)逆境胁迫应答方面均上调表达。【结论】在芸豆中鉴定出19个PvGH3基因,通过qRT-PCR证明这19个PvGH3基因能不同程度地响应非生物胁迫,可为PvGH3的抗逆功能分析提供理论依据。

关键词：芸豆 GH3基因家族生物信息学分析表达分析实时荧光定量PCR

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Reduction of Sensitivity to Sintering Temperature for Nd-Fe-B magnets through Zr and Nb Additions

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Journal of materials Science & Technology 2009年第5期25卷 629-632页

作者： Mi Yan Xigui Cui Lianqing Yu tianyu ma State Key Laboratory of Silicon materials Department of Materials Science and Engineering Zhejiang University Hangzhou 310027 China

To reduce the sensitivity of grain growth to sintering temperature for improving property consistency of sintered Nd-Fe-B magnets, combined additions of Zr and Nb were investigated. It was found that when Zr content was increased to 0.07 at. pct, abnormal grain growth was effectively hindered even when the sintering temperature reached 1100℃. With combined additions of 0.07 at. pct Zr and 0.07 at. pct Nb, the sensitivity of grain growth to sintering temperature was greatly reduced consistency than the magnets containing no Zr and also improved. The magnets sintered at 1100℃ showed higher property Nb. In addition, the magnetic properties of magnets were also improved.

关键词： Sintered Nd-Fe-B magnet magnetic properties Consistency Sintering temperature

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Grain boundary restructuring and La/Ce/Y application in Nd–Fe–B magnets

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Chinese Physics B 2019年第7期28卷 25-53页

作者： Mi Yan Jiaying Jin tianyu ma School of materials Science and Engineering State Key Laboratory of Silicon MaterialsKey Laboratory of Novel Materials for Information Technology of Zhejiang Province Zhejiang University

Since the 1980 s, Nd–Fe–B with largest energy product(BH)max approaching the theoretical limit has become the landmark of permanent magnetic *** application spectrum for Nd–Fe–B continues to expand over time both in the industrial and commercial sectors, which leads to growing research interests for solving the long-standing drawbacks of Nd–Fe–B, i.e., poor corrosion resistance, low coercivity, high Dy/Tb and low La/Ce/Y *** the above obstacles, we aim to present the novel grain boundary restructuring(GBR) approach, from GB design, processing, to structure evolution and property evaluation with a focus on the corrosion and coercivity mechanism of the restructured 2:14:1-typed *** with an introduction to the fundamental of GBR, two representative examples,high-electrode-potential(Pr, Nd)32.5Fe62.0Cu5.5 and low-melting-point Dy71.5Fe28.5, are given with detailed descriptions of the advantages of GBR to enhance the intrinsic anti-corrosion stability and to strengthen the coercivity at low Dy ***–property correlations are established to understand the critical importance of regulating the restructured GB phase to maximize the all-round performance of the 2:14:1-typed permanent *** at sustainable and balanced development of rare earth(RE) industry, the proceeding section proposes new prototypes of La–Ce and Y–Ce co-substitutions with dual benefits of stabilizing the 2:14:1 tetragonal phase and strengthening the intrinsic hard *** findings of additional REFe2 intergranular phase delight that the GBR approach also opens up a new horizon of research and application to develop high-performance La/Ce/Y-rich permanent magnets with deliberately tailored GB phase.

关键词： grain boundary restructuring coercivity corrosion resistance Dy/Tb La/Ce/Y

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Stabilities,mechanical and thermodynamic properties of Al-RE intermetallics:A first-principles study

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Journal of Rare Earths 2022年第2期40卷 345-352,I0006页

作者： Tongyu Liu tianyu ma Yingmin Li Yuyan Ren Weihua Liu School of materials Science and Engineering Shenyang University of TechnologyShenyang 110870China School of Mechanical Engineering Weifang University of Science and Technology Weifang 262700China

Stabilities,mechanical and thermodynamic properties of 87 intermetallics in Al-RE binary system were studied by first-principles based on density functional theory(DFT).The results show that the calculated stabilities at T=0 K are in good agreement with experimental ***2 RE intermetallics exhibit the best stability in Al-RE binary compounds;and the stabilities in descending order are Al2 RE,Al3 RE,AlRE,Al11RE_(3),AlRE2 and AlRE_(3).The calculated Al-RE intermetallics possess mechanical *** hardness and strength of the most Al-RE intermetallics are greater than pure aluminum except AlCe,AlPr,AlEu and *** hardness and strength in descending order are Al11RE_(3),Al3 RE,Al2 RE and *** of AlRE intermetallics exhibit ductility;the others are *** heat capacities of Al-RE intermetallics in ascending order are Al-Sc,Al-Y,*** the contrary,the coefficient of thermal expansion(CTE)in ascending order is Al-lanthanides,Al-Y and Al-Sc.

关键词： Rare earth First-principles Stability Mechanical modulus Heat capacity

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