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南蛇藤总萜抑制中性粒细胞胞外诱捕网形成的作用与机制研究

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扬州大学学报（农业与生命科学版） 2024年第1期45卷 75-83,138页

作者：郭雅洁朱淼刘延庆陶丽扬州大学医学院/国家中医药管理局胃癌毒邪重点论治研究室江苏扬州225009

为探索南蛇藤总萜(the total terpenoids of Celastrus orbiculatus Thunb.,TTC)对中性粒细胞胞外诱捕网(neutrophil extracellular traps,NETs)形成及其作用机制,通过分离与制备中性粒细胞,建立佛波酯(phorbol 12-myristate 13-acetate,PMA)诱导的NETs形成细胞模型。利用瑞氏-姬姆萨染色、扫描电镜与免疫荧光技术研究南蛇藤总萜对NETs形成及其生物学标志的影响,并利用Annexin V/PI试验研究南蛇藤总萜对中性粒细胞凋亡的影响。结果表明:南蛇藤总萜能剂量依赖性地抑制PMA诱导的NETs形成;南蛇藤总萜(80μg·mL^(-1))可阻断中性粒细胞弹性蛋白酶(neutrophil elastase,NE)的释放,并破坏NETs相关DNA-NE复合物的形成;南蛇藤总萜(80μg·mL^(-1))可显著抑制PMA诱导的瓜氨酸化组蛋白H3(citrullinated histone H3,CitH3)的表达水平;南蛇藤总萜可剂量依赖性地促进中性粒细胞凋亡。综上,南蛇藤总萜对中性粒细胞NETs的形成具有抑制作用,其机制可能与其直接诱导中性粒细胞凋亡有关。

关键词：南蛇藤总萜中性粒细胞胞外诱捕网凋亡中性粒细胞弹性蛋白酶瓜氨酸化组蛋白H3

复合材料翼型结构件内部缺陷的超声相控阵检测技术应用

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当代化工研究 2024年第12期 166-168页

作者：付滔郭亚杰湖南弘辉科技有限公司湖南413000 湖南千金湘江药业股份有限公司湖南412000

复合材料凭借其优良的特性,在航天航空飞行器上得到了广泛的应用,随着飞行器中复合材料占比的提升趋势,复合材料结构件在制造或使用过程产生的各种形式的缺陷,可能导致重大经济损失或出现安全问题。超声相控阵技术作为可以在不破坏产品... 详细信息

复合材料凭借其优良的特性,在航天航空飞行器上得到了广泛的应用,随着飞行器中复合材料占比的提升趋势,复合材料结构件在制造或使用过程产生的各种形式的缺陷,可能导致重大经济损失或出现安全问题。超声相控阵技术作为可以在不破坏产品且在经济成本低的基础上能够快速、准确地检测出的缺陷,对复合材料结构件的应用尤为重要。

关键词：复合材料结构件内部缺陷超声相控阵低成本检测技术应用

“数字中国”建设背景下数字素养政策文本量化评价

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未来与发展 2024年第1期48卷 62-70页

作者：毛丰付刘芸芸郭亚洁浙江工商大学图书馆浙江杭州310018 浙江工商大学经济学院浙江杭州310018 山西航天清华装备有限责任公司山西长治046012

数字素养是数字中国建设至关重要的一环,对数字素养政策进行梳理分析能更好地了解当前的发展趋势与整体布局。本研究运用文本挖掘以及PMC指数模型等研究方法,对2015—2022年中央颁布的有关数字素养的37项政策条例进行了量化分析。分析发... 详细信息

数字素养是数字中国建设至关重要的一环,对数字素养政策进行梳理分析能更好地了解当前的发展趋势与整体布局。本研究运用文本挖掘以及PMC指数模型等研究方法,对2015—2022年中央颁布的有关数字素养的37项政策条例进行了量化分析。分析发现,现存的有关数字素养政策总体质量较高,基本处于优秀、及格的范围;但个体之间差异较大,存在建议内容不够详细、作用范围较窄、预测性和监管性略有欠缺、切入视角单一等问题。基于以上结论,本研究对未来数字素养政策的制定做出展望,也对未来数字素养的学术研究方向做出尝试性设想,以期为数字中国建设目标的实现助力。

关键词：数字素养文本挖掘量化评价 PMC指数模型

宁东煤田横城矿区太原组煤中关键金属的物质来源和富集机理

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地质学报 2024年第8期98卷 2336-2350页

作者：黄鹏程郭雅杰史禹韬曹佳亮李宝庆田继军姬晓燕上官云飞庄新国马少东中国地质大学(武汉)地质调查研究院湖北武汉430074 中国地质大学(武汉)构造与油气资源教育部重点实验室湖北武汉430074 宁夏回族自治区煤炭地质局宁夏银川750001

对宁东煤田横城矿区太原组9号煤层进行了矿物学和地球化学研究,以便查明煤中关键金属的分布、赋存和富集特征,并评价其综合利用前景。研究结果表明:①横城矿区9号煤以高的镜质组含量、特低—低灰分产率和中—高硫含量为特征。②煤中矿... 详细信息

对宁东煤田横城矿区太原组9号煤层进行了矿物学和地球化学研究,以便查明煤中关键金属的分布、赋存和富集特征,并评价其综合利用前景。研究结果表明:①横城矿区9号煤以高的镜质组含量、特低—低灰分产率和中—高硫含量为特征。②煤中矿物主要由高岭石组成,以细胞充填状、透镜状和薄层状等形式存在。煤层底板中矿物主要由石英、高岭石和白云母组成,其主要为碎屑成因。③煤层中常量元素主要由SiO_(2)和Al_(2)O_(3)组成,煤中Li、Zr、Nb、Hf、Pb和Th的含量达到轻度富集—富集程度,其中Li、Pb和Th主要赋存于高岭石,Zr和Hf赋存于锆石,Nb赋存于高岭石和锐钛矿。矿区9号煤层形成于受海水影响的潮坪-潟湖环境,煤层下部形成于铁源供给不足的低位沼泽环境,煤层上部形成于铁源严重不足的高位沼泽环境,故下部煤层中硫以黄铁矿硫为主而上部以有机硫为主。煤中碎屑物质主要来源于阴山古陆和阿拉善地块,阴山古陆主要提供了元古宙的陆源碎屑物质,阿拉善地块主要供给了早石炭世的碎屑物质,此外也有少量的火山灰和奥陶系灰岩风化残积物进入到含煤盆地。煤中的Li、Zr、Nb等关键金属的富集主要受控于长英质的碱性—过碱性物质输入量的多少,同时水/岩作用过程也导致了关键金属的活化、迁移和重新分配。煤灰中Li_(2)O含量超过其边界品位,REO、Ga、Zr和REY接近相应边界品位,故可考虑Li-Ga-Zr-REY等的综合开发利用。

关键词：关键金属赋存状态富集机理宁东煤田太原组

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Synthesis of nearly spherical AlN particles by an in-situ nitriding combustion route

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Journal of Advanced Ceramics 2021年第2期10卷 291-300页

作者： Zhilei Wei Kang Li Bangzhi Ge Chaowei guo Hongyan Xia yajie guo Zhongqi Shi State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an710049China Engineering Research Center of Transportation Materials of Ministry of Education School of Materials Science and EngineeringChang’an UniversityXi’an710064China

Spherical AlN powders with micrometer size have attracted great attention owing to their good fluidity and dispersity. However, the industrial preparation methods usually require high temperature and long soaking time, which lead to the high cost and limit the wide application of the products. Herein, nearly spherical AlN particles with the average size of 2.5 μm were successfully synthesized via an in-situ combustion synthesis method. The effect of N_(2) pressure, NH_(4)Cl content, and Al particle size on the combustion reaction procedure, phase composition, and microstructure of the products was systematically investigated. The results showed that the decreased N_(2) pressure, increased NH_(4)Cl content, and Al particle size led to the decreasing of combustion temperature and speed, which further affected the morphology of the products. As a result, low N_(2) pressure(0.2 MPa), a small amount of NH4Cl(0.5 wt%), and fine Al particles(~2.5 μm) contributed to a moderate combustion temperature and facilitated the formation of nearly spherical AlN particles. In addition, based on the gas-releasing assisted quenching experiments and thermo-kinetic analysis, a two-step growth mechanism for the nearly spherical AlN particles was rationally proposed. The present method shows the advantages of low cost and high efficiency for preparing nearly spherical AlN particles, which can be used as raw materials for electronic substrates and fillers for packaging materials.

关键词： combustion synthesis AlN microstructure growth mechanism

Brazing of WC–8Co cemented carbide to steel using Cu–Ni–Al alloys as filler metal: Microstructures and joint mechanical behavior

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Journal of Materials Science & Technology 2018年第7期34卷 1180-1188页

作者： Xiangzhao Zhang Guiwu Liu Junnan Tao yajie guo Jingjing Wang Guanjun Qiao School of Materials Science and Engineering Jiangsu University Engineering Research Center of Transportation Materials of Ministry of Education School of Materials Science and Engineering Chang'an University School of Materials Science and Engineering Shanghai University State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University

Three novel Cu-Ni-A1 brazing filler alloys with Cu/Ni weight ratio of 4：1 and 2.5-10 wt% Al were developed and characterized, and the wetting of three Cu-Ni-Al alloys on WC-8Co cemented carbide were investigated at 1190-1210 ℃ by the sessile drop technique. Vacuum brazing of the WC-8Co cemented carbide to SAE1045 steel using the three Cu-Ni-Al alloys as filler metal was further carried out based on the wetting test results. The interfacial interactions and joint mechanical behaviors involving microhardness, shear strength and fracture were analyzed and discussed. The experimental results show that all the three wetting systems present excellent wettability with final contact angles of less than 5 °and fast spreading. An obvious degeneration layer with continuous thin strip forms in the cemented carbide adjacent to the Cu-Ni-A1/WC-8Co interface. The variation of microhardness in the joint cross-section is closely related to the interactions （such as diffusion and solid solution） of WC-8Co/Cu-Ni-Al/steel sys- tem. Compared with the other two brazed joints, the WC-8Co/Cu-19Ni-SAl/steel brazed joint presents more reliable interlayer microstructure and mechanical property while brazing at the corresponding wetting temperatures for 5 rain, and its average shear strength is over 200 MPa after further optimizing the brazing temperature and holding time. The joint shear fracture path passes along the degeneration layer, Cu-Ni-A1/WC-8Co interface and brazing interlayer, showing a mixed ductile-brittle fracture.2018 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science ＆ Technology.

关键词： Cu-Ni-Al alloy Cemented carbide Brazing Microstructures Mechanical properties

Mullite whiskers prepared by molten salt method using Si powders

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Journal of Advanced Ceramics 2012年第4期1卷 283-289页

作者： Wei WANG Hongwei LI yajie guo Qiang SUN Chen CHEN Department of Chemical Engineering College of Environment Science and EngineeringChang’an UniversityXi’an 710054China College of Materials Science and Engineering Chang’an UniversityXi’an 710061China

Mullite whiskers were prepared from Si powders in molten Al2(SO4)3-Na2SO4 mixture salts with different Al/Si molar ratio(R)of raw *** resulting mullite whiskers,had been investigated using X-ray diffraction(XRD),scanning electron microscopy(SEM),energy dispersive spectrometer(EDS)and infrared spectroscopy analysis(FT-IR).Mullite phase was obtained in molten salts when the temperature reached at 850℃.SEM and EDS results revealed that two kinds of microstructures were formed in the final product,Al-rich mullite pellets and clusters of tiny mullite crystals,and the content of Al-rich mullite pellets increased with the higher Al/Si molar ratio(R)adopted in raw materials.A new oxidation-dissolution mechanism was proposed to explain mullite whiskers *** to thermodynamic analysis,mullite phase might be spontaneously formed as the temperature reached the decomposition temperature of aluminum sulfate(1023 K).

关键词： chemical preparation whiskers mullite infrared spectroscopy

The size distribution of airborne bacteria and human pathogenic bacteria in a commercial composting plant

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Frontiers of Environmental Science & Engineering 2021年第3期15卷 87-96页

作者： Min Gao Ziye Yang yajie guo Mo Chen Tianlei Qiu Xingbin Sun Xuming Wang Beijing Key Laboratory of Agricultural Genetic Resources and Biotechnology Beijing Agro-Biotechnology Research CenterBeijing Academy of Agriculture and Forestry SciencesBeijing 100097China College of Forestry Northeast Forestry UniversityHarbin 150040China

Composting plants are regarded as one of the important sources of environmental ***,limitations in the size distribution of airborne bacteria have prevented our comprehensive understanding of their risk to human health and their dispersal *** this study,different sizes of airborne bacteria were collected using an eight-stage impactor from a full-scale composting ***-related abundance and communities of airborne bacteria as well as human pathogenic bacteria(HPB)were investigated using 16S rRNA gene sequencing coupled with droplet digital *** results indicate that the bacterial concentrations from the eight stages were approximately 10^(4)-105copies/m^(3).Although no statistical correlation was detected between the particle size and the Shannon index,the influence of size on bacterial lineages was observed in both composting and packaging *** airborne bacteria from different stages,the dominant phyla were Firmicutes,Proteobacteria,and Actinobacteria,and the dominant genera was *** out of eight HPB with a small geometric mean aerodynamic diameter had a high concentration in composting *** on diameters of 2.42 to 5.09μm,most HPB in the composting areas were expected to be deposited on the bronchus and secondary ***,in the packaging areas,the deposition of HPB(diameters 3.70 to 8.96μm)occurred in the upper part of the respiratory *** results on the size distribution,abundance,and diversity of these bacteria offer important information for the systematic evaluation of bacterial pathogenicity and the potential health impacts on workers in composting plants and the surrounding residents.

关键词： Size distribution Airborne bacteria Biological diversity Human pathogenic bacteria Composting plants

Idebenone alleviates doxorubicin-induced cardiotoxicity by stabilizing FSP1 to inhibit ferroptosis

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Acta Pharmaceutica Sinica B 2024年第6期14卷 2581-2597页

作者： Hongliang Qiu Sihui Huang Yuting Liu Libo Liu Fengming guo Yingying guo Dan Li Xianfeng Cen yajie Chen Meng Zhang Yan Che Man Xu Qizhu Tang Department of Cardiology Renmin Hospital of Wuhan UniversityWuhan 430060China Hubei Key Laboratory of Metabolic and Chronic Diseases Wuhan 430060China

Doxorubicin(DOX)-mediated cardiotoxicity can exacerbate mortality in oncology patients,but related pharmacotherapeutic measures are relatively *** was recently identified as a major mechanism of DOX-induced ***,a novel ferroptosis inhibitor,is a well-described clinical drug widely ***,its role and pathological mechanism in DOX-induced cardiotoxicity are still *** this study,we demonstrated the effects of idebenone on DOX-induced cardiotoxicity and elucidated its underlying mechanism.A single intraperitoneal injection of DOX(15 mg/kg)was administrated to establish DOX-induced *** results showed that idebenone significantly attenuated DOX-induced cardiac dysfunction due to its ability to regulate acute DOX-induced Fe^(2+)and ROS overload,which resulted in *** and BLI further revealed that idebenone's anti-ferroptosis effect was mediated by ***,idebenone increased FSP1 protein levels but did not affect Fsp1 mRNA levels in the presence of *** could form stable hydrogen bonds with FSP1 protein at K355,which may influence its association with *** results confirmed that idebenone stabilized FSP1 protein levels by inhibiting its ubiquitination *** conclusion,this study demonstrates idebenone attenuated DOX-induced cardiotoxicity by inhibiting ferroptosis via regulation of FSP1,making it a potential clinical drug for patients receiving DOX treatment.

关键词： Idebenone DOX-induced cardiotoxicity Ferroptosis FSP1 Ubiquitination Lipid peroxidation Iron overload Clinical translation