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Fine-tuning MAVS- and STING-mediated antiviral innate immunity

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National Science Review 2015年第3期2卷 262-264页

作者： xingguang liu Xuetao Cao National Key Laboratory of Medical Immunology& Institute of Immunology Second Military Medical University National Key Laboratory of Medical Molecular Biology & Department of Immunology Institute of Basic Medical Sciences Chinese Academy of Medical Sciences

The pathogen-associated molecules or nucleic acids derived from the invading pathogens can initiate the production of type I interferons(IFNs)and IFN-inducible genes,resulting in the establishment of an efective antimicrobial environment.In case of viral infection,nucleic acids from viruses are detected by patern recognition receptors mainly including several endosomal members of

关键词： Fine-tuning MAVS and STING-mediated antiviral innate immunity IFN

Numerical simulation and damage analysis of fissure field evolution law in a single coal seam mining

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International Journal of Mining Science and Technology 2012年第6期22卷 853-856页

作者： Feng Gao xingguang liu Chaofeng Ge Hongmei Cheng State Key Laboratory of Geomechanics and Deep Underground Engineering China University of Mining & Technology School of Mechanics and Civil Engineering China University of Mining & Technology

Based on the different deformation and failure laws of coal and rock materials under tensile or compressive loads,the damage variable was defined to divide three phases from the damage and rupture point of view in order to reveal the fissured field evolution characteristics and spatial distribution of coal and rock in the single coal seam mining with low permeability and rich methane.According to the corresponding damage constitutive equations,the secondary development of the finite element program was completed.The fissures field evolution law of a coal mine with single coal seam mining was calculated and analyzed by this new program and the distribution areas and failure degree of the surrounding coal and rock structures with damage,fissure or rupture are given on the condition of mining.This paper provides a scientific basis for quantitative research and evaluation of the safe simultaneous production of coal and gas.

关键词： Single coal seam Damage Fissure Rupture Finite element

应力及含水状态对裂隙花岗岩蠕变特性的影响研究

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岩石力学与工程学报 2024年第4期43卷 907-917页

作者：王春萍廖益林刘建锋刘健赵星光陈亮王璐核工业北京地质研究院北京100029 国家原子能机构高放废物地质处置创新中心北京100029 四川大学水利水电学院四川成都610065 西华大学建筑与土木工程学院四川成都610039

为研究应力及含水状态对裂隙花岗岩蠕变特性的影响,以我国高放废物地质处置甘肃北山预选区完整花岗岩及含不同倾角裂隙的花岗岩为研究对象,采用岩石高温三轴流变试验系统,开展不同围压条件下的应力多级加载蠕变试验和不同含水状态下的... 详细信息

为研究应力及含水状态对裂隙花岗岩蠕变特性的影响,以我国高放废物地质处置甘肃北山预选区完整花岗岩及含不同倾角裂隙的花岗岩为研究对象,采用岩石高温三轴流变试验系统,开展不同围压条件下的应力多级加载蠕变试验和不同含水状态下的单轴蠕变试验。试验结果表明,裂隙花岗岩横向变形的蠕变特征更加显著,且横向稳态蠕变率略高于轴向稳态蠕变率。随着应力水平的提高,轴向应变呈现出线性增长关系,而横向应变、轴向及横向稳态蠕变率均呈现出指数函数增长关系。在围压一致且偏应力相同的条件下,裂隙倾角越大,轴向和横向应变越大,轴向和横向稳态蠕变率也越高。饱和状态下,花岗岩的稳态蠕变率显著提高,岩体受力更容易发生变形,导致花岗岩在更低的蠕变荷载或更短的蠕变历时下即发生破坏。当裂隙倾角为45°或60°时,饱和试样的破坏时间仅为干燥试样的1.05‰或0.84‰。倾角30°,45°和60°裂隙花岗岩的蠕变破坏形式分别为穿裂隙面破坏、穿裂隙面破坏和沿裂隙面滑移并存的复合破坏以及沿裂隙面的滑移破坏,10 MPa围压及干燥、饱和状态均不会对其破坏形式产生显著影响。

关键词：岩石力学花岗岩蠕变裂隙倾角含水条件破坏形式

Methyltransferase Dot1l preferentially promotes innate IL-6 and IFN-β production by mediating H3K79me2/3 methylation in macrophages

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Cellular & Molecular Immunology 2020年第1期17卷 76-84页

作者： Xiang Chen xingguang liu Yunkai Zhang Wanwan Huai Qingqing Zhou Sheng Xu Xi Chen Nan Li Xuetao Cao National Key Laboratory of Medical Immunology&Institute of Immunology Second Military Medical UniversityShanghai 200433China Institute of Immunology Zhejiang University School of MedicineHangzhou 310058China Department of Immunology&Center for Immunotherapy Institute of Basic Medical SciencesPeking Union Medical CollegeChinese Academy of Medical SciencesBeijing 100005China

Epigenetic modification,including histone modification,precisely controls target gene expression.The posttranscriptional regulation of the innate signaling-triggered production of inflammatory cytokines and type I interferons has been fully elucidated,whereas the roles of histone modification alteration and epigenetic modifiers in regulating inflammatory responses need to be further explored.Di/tri-methylation modifications of histone 3 lysine 79(H3K79me2/3)have been shown to be associated with gene transcriptional activation.Disruptor of telomeric silencing-1-like(Dot1l)is the only known exclusive H3K79 methyltransferase and regulates the proliferation and differentiation of tumor cells.However,the roles of Dot1l and Dot1l-mediated H3K79 methylation in innate immunity and inflammatory responses remain unclear.Here,we found that H3K79me2/3 modification levels at the Il6 and Ifnb1 promoters,as well as H3K79me2 modification at the Tnfαpromoter,were increased in macrophages activated by Toll-like receptor(TLR)ligands or virus infection.The innate signals upregulated Dot1l expression in macrophages and THP1 cells.Dot1l silencing or a Dot1l inhibitor preferentially suppressed the production of IL-6 and interferon(IFN)-βbut not of TNFαin macrophages and THP1 cells triggered by TLR ligands or virus infection.Dot1l was recruited to the proximal promoter of the Il6 and Ifnb1 but not Tnfαgene and then mediated H3K79me2/3 modification at the Il6 and Ifnb1 promoters,consequently facilitating the transcription and expression of Il6 and Ifnb1.Thus,Dot1l-mediated selective H3K79me2/3 modifications at the Il6 and Ifnb1 promoters are required for the full activation of innate immune responses.This finding adds new insights into the epigenetic regulation of inflammatory responses and pathogenesis of autoimmune diseases.

关键词： H3K79me2/3 Dot1l epigenetic regulation IL-6 IFN-β macrophages inflammation

KDM2B promotes IL-6 production and inflammatory responses through Brg1-mediated chromatin remodeling

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Cellular & Molecular Immunology 2020年第8期17卷 834-842页

作者： Qingqing Zhou Yunkai Zhang Bo Wang Wenhui Zhou Yong Bi Wanwan Huai Xi Chen Yihan Chen Zhongmin liu xingguang liu Zhenzhen Zhan Institute of Heart Failure Shanghai East HospitalTongji University School of Medicine200120ShanghaiChina National Key Laboratory of Medical Immunology&Institute of Immunology Second Military Medical University200433ShanghaiChina Shanghai Fourth People’s Hospital Tongji University School of Medicine200081ShanghaiChina Institute of Immunology Zhejiang University School of Medicine310058HangzhouChina Key Laboratory of Arrhythmias of the Ministry of Education of China Shanghai East HospitalTongji University School of Medicine200120ShanghaiChina

IL-6 plays important and pleiotropic roles in infection and inflammatory diseases,and its production needs to be tightly regulated.However,the epigenetic mechanism underlying Il6 gene transcription remains to be fully elucidated.Here,we report that lysine-specific demethylase 2b(KDM2B),which demethylates H3K4me3 and H3K36me2,is required in macrophages and dendritic cells for the induction of IL-6 but not TNF-α,IL-1,and IFN-β.Compared to wild-type mice,KDM2B-deficient mice were more resistant to endotoxin shock and colitis,with a less severe inflammatory pathogenesis phenotype and decreased IL-6 production in sera.KDM2B selectively bound the Il6 promoter but did not alter histone demethylation;instead,KDM2B interacted with Brahma-related gene 1(Brg1),the core ATPase subunit of SWI/SNF chromatin remodeling complexes,to facilitate chromatin accessibility of the Il6 promoter.Furthermore,KDM2B directly recruited RNA Polymerase II to further initiate and promote Il6 transcription.Thus,our finding identifies a novel nonclassical function of KDM2B in gene-specific transcription initiation and enhancement of Il6 independent of its demethylase activity and adds new insight into the specific epigenetic modification mechanism of inflammatory immune responses.

关键词： KDM2B IL-6 Brg1 Chromatin remodeling Inflammation

基于密集残差连接U型网络的噪声图像超分辨率重建

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工矿自动化 2024年第2期50卷 63-71页

作者：刘鹏南李龙张紫豪朱星光程德强中国矿业大学信息与控制工程学院江苏徐州221116 山东黄金矿业(莱西)有限公司山东青岛266600

现有的图像超分辨率重建网络难以适用于煤矿井下噪声密集的应用场景,且多数网络通过增加深度提升性能会导致无法有效提取关键特征、高频信息丢失等问题。针对上述问题,提出了一种密集残差连接U型网络,用于对低分辨率噪声图像进行超分辨... 详细信息

现有的图像超分辨率重建网络难以适用于煤矿井下噪声密集的应用场景,且多数网络通过增加深度提升性能会导致无法有效提取关键特征、高频信息丢失等问题。针对上述问题,提出了一种密集残差连接U型网络,用于对低分辨率噪声图像进行超分辨率重建。在特征提取路径中引入基于密集残差连接的去噪模块,通过密集连接的方式对图像特征进行充分提取,再利用残差学习的特点对低分辨率噪声图像进行有效去噪;在重建路径中引入残差特征注意力蒸馏模块,通过在残差块中融入增强特征注意力块,对不同空间的特征赋予不同的权重,加强网络对于图像关键特征的提取能力,同时减少图像细节特征在残差块中的损失,从而更好地恢复图像细节信息。在煤矿井下图像数据集及公共数据集上进行了对比实验,结果表明:在客观评价指标上,所提网络的结构相似度、图像感知相似度均优于对比网络,且在复杂度及运行速度上有着较好的均衡;在主观视觉效果上,所提网络重建的图像基本消除了原有图像噪声,有效恢复了图像的细节特征。

关键词：噪声图像超分辨率重建密集残差连接 U型网络去噪模块残差特征注意力蒸馏模块

山东省青少年电子烟和卷烟双重使用行为的研究

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中华流行病学杂志 2024年第4期45卷 548-552页

作者：周培静王连森刘维量杨兴光刘佳佳魏霞冷艳山东省疾病预防控制中心济南250014

目的了解山东省青少年电子烟和卷烟的双重使用现状及其影响因素,探讨产生双重使用的原因。方法采用分层多阶段整群随机抽样方法,在山东省共抽取中学在校学生7999人进行自填问卷调查。对样本进行加权后,使用SPSS 25.0软件复杂抽样模块对... 详细信息

目的了解山东省青少年电子烟和卷烟的双重使用现状及其影响因素,探讨产生双重使用的原因。方法采用分层多阶段整群随机抽样方法,在山东省共抽取中学在校学生7999人进行自填问卷调查。对样本进行加权后,使用SPSS 25.0软件复杂抽样模块对数据进行分析。结果山东省青少年电子烟和卷烟双重尝试的比例为7.7%,双重使用的比例为1.3%。男生、好友吸烟、过去7 d二手烟暴露是双重使用的危险因素。双重使用者与仅吸卷烟者相比,在戒烟方面的认知和行为差异无统计学意义(P>0.05),双重使用者吸电子烟的原因主要为好奇。结论山东省青少年电子烟和卷烟双重使用行为普遍存在,其影响因素与传统卷烟类似。双重使用并非戒烟的过渡阶段,双重使用者未来持续吸烟的可能性较高,应引起关注和重视。

关键词：烟草双重使用青少年

Mechanistic study of ventricular hook anchor for heart valve replacement or repair

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Medicine in Novel Technology and Devices 2020年第1期5卷 13-20页

作者： Ran Zhang xingguang liu Si Chen Shamini Parameswaran Zhaoming He Research Center of Fluid Machinery Engineering&Technology Jiangsu UniversityZhenjiangJiangsu Province212013PR China Division of Cardiac Surgery of People’s Hospital of Gansu Province Lanzhou730000PR China Division of Cardiothoracic Surgery Yale UniversityNew HavenCT06519USA Department of Mechanical Engineering Texas Tech UniversityLubbockTX79409USA Beijing Advanced Innovation Center for Biomedical Engineering Beihang UniversityBeijing100083PR China

Objective:The objective of this study was to investigate the mechanics of ventricular anchor for heart valve repair or replacement.Methods:Thirteen anchors were designed based on six geometric parameters of the anchor teeth:width,thickness,root length,radius of curvature,tip angle,and tip length.Finite element method was applied to simulate the process of the anchor compressing into a sheath.The Von-Mises strain,peak pulling force,and bite depth were evaluated.An experiment was performed to validate the simulation.Results:The maximum Von-Mises strain was at the contact region of the anchor in a sheath where the teeth were compressed against one another and were distorted.The maximum strain increased with an increase in tooth width,thickness,radius of curvature and tip angle.The peak pulling force increased as tooth thickness and width increased,and radius of curvature decreased.Both the radial and axial bite depths increased with an increase in the tip length at the tip length3 mm.The radial bite depth increased with an increase in the radius of curvature.Conclusion:1)the maximum strain depends primarily on the tooth width,thickness,radius of curvature and tip angle;2)the peak pulling force depends primarily on the tooth width,thickness,radius of curvature;3)the axial bite depth depends primarily on the tip length at the tip length3 mm.The radial bite depth depends on the radius of curvature and the tip length at the tip length>3 mm.The study provides guidance for ventricular anchor design.

关键词： Heart valve repair Anchor Finite element analysis Mechanics

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裂隙花岗岩非线性蠕变本构模型及参数分析

工程科学与技术 2024年第4期56卷 141-149页

作者：王春萍刘建锋陈亮刘健赵星光马洪素核工业北京地质研究院北京100029 国家原子能机构高放废物地质处置创新中心北京100029 四川大学水利水电学院四川成都610065

裂隙花岗岩的蠕变特性对高放废物地质处置库的长期稳定性和安全性至关重要。本文基于裂隙花岗岩在不同应力条件下的蠕变试验结果,结合蠕变过程中应力产生的损伤累积的影响,提出一种考虑损伤的弹黏塑性体。通过将经典Burgers模型的黏性... 详细信息

裂隙花岗岩的蠕变特性对高放废物地质处置库的长期稳定性和安全性至关重要。本文基于裂隙花岗岩在不同应力条件下的蠕变试验结果,结合蠕变过程中应力产生的损伤累积的影响,提出一种考虑损伤的弹黏塑性体。通过将经典Burgers模型的黏性元件替换为分数阶黏弹性元件,将黏弹性体替换为考虑损伤的弹黏塑性体的方法,构建了裂隙花岗岩非线性蠕变本构模型,并推导出模型在3维应力状态下的本构方程。通过对倾角30°及45°单裂隙花岗岩在不同应力条件下蠕变试验数据的拟合分析,确定了模型参数,验证了模型的适用性和合理性,获得了各模型参数随应力水平的变化规律。通过模型参数的敏感性分析,揭示了分数阶导数、损伤参数,以及应力水平对裂隙花岗岩蠕变应变的影响规律,并验证了裂隙花岗岩非线性蠕变本构模型在特殊条件下可退化为经典Burgers模型。研究表明,本文提出的裂隙花岗岩非线性蠕变本构模型能够准确地描述裂隙花岗岩蠕变破坏全过程的3个阶段,尤其是加速蠕变阶段应变随时间非线性增长的过程。

关键词：裂隙花岗岩蠕变非线性模型分数阶导数参数分析