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Computational Insights into the Interactions of Farnesoid X Receptor with Fargesone A,a Natural Product from Magnolia fargesii

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Chemical Research in Chinese Universities 2025年第1期41卷 146-154页

作者： ZHANG li CHEN Yaqiong li Weihua School of Pharmacy Shanghai Key Laboratory of Molecular ImagingShanghai University of Medicine and Health SciencesShanghai201318P.R.China School of Pharmacy East China University of Science and TechnologyShanghai200237P.R.China

Farnesoid X receptor(FXR)is a ligand-activated nuclear receptor and plays important roles in the regulation of metabolism and homeostasis of several important physiological substances,such as bile acids,glucose,and *** such,FXR has become a promising therapeutic target for the treatment of several metabolic diseases and liver ***,fargesone A(FA),a natural product from Magnolia fargesii was identified to be a novel,potent FXR agonist that demonstrated good in vitro and in vivo ***,the detailed interaction mechanism of FA with FXR remains *** this study,we employed multiple computational approaches including molecular docking,molecular dynamics simulation,and binding free energy calculation to address the *** comparisons of the structural dynamics and binding free energies,an optimal binding mode was identified,in which FA interacts with FXR via a direct hydrogen bond with His447 and hydrophobic interactions with multiple residues,such as Leu287,Met290,Met328,Ile352,and *** mutants,namely,H447F and L287N,were further constructed to validate the importance of the identified *** anticipate that these findings could be helpful for future rational design of new FA analogues targeting FXR.

关键词： Farnesoid X receptor(FXR) Binding mode Molecular docking Molecular dynamics Fargesone A

Constraints on holographic QCD phase transitions from PTA observations

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 67-74页

作者： Song He li li Sai Wang Shao-Jiang Wang Center for Theoretical Physics and College of Physics Jilin UniversityChangchun 130012China School of Physical Science and Technology Ningbo UniversityNingbo 315211China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences(UCAS)Hangzhou 310024China Theoretical Physics Division Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China School of Physical Sciences University of Chinese Academy of Sciences(UCAS)Beijing 100049China Max Planck Institute for Gravitational Physics(Albert Einstein Institute) Am Muhlenberg 1Golm 14476Germany

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition,yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT)left *** specific baryon chemical poten-tial,the first-order QCD phase transition agrees with the observational constraint of baryon ***,therefore,provides a scenario for phase transition gravitational waves(GWs)within the standard model of particle *** these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA)observations,the duration of this FoPT can be well constrained,and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

固溶温度对马氏体时效钢00Ni14Cr3Mo3Ti组织和力学性能的影响

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特殊钢 2009年第3期30卷 61-62页

作者：杨维宇丁雅莉杨卓越李保成中北大学材料科学与工程学院太原030051 中国钢研科技集团公司结构材料研究所北京100081

研究了马氏体时效钢00Ni14Cr3Mo3Ti(%:0.002C、14.06Ni、3.19Cr、3.06Mo、1.32Ti)750～1 050℃固溶处理的组织和力学性能。结果表明,≤900℃固溶处理,该钢奥氏体晶粒和强度无明显变化,固溶温度超过900℃时钢的奥氏体晶粒显著增大,钢的... 详细信息

研究了马氏体时效钢00Ni14Cr3Mo3Ti(%:0.002C、14.06Ni、3.19Cr、3.06Mo、1.32Ti)750～1 050℃固溶处理的组织和力学性能。结果表明,≤900℃固溶处理,该钢奥氏体晶粒和强度无明显变化,固溶温度超过900℃时钢的奥氏体晶粒显著增大,钢的强度呈下降趋势。当固溶温度由750℃增加至900℃时,随固溶处理温度提高,钢中Fe_2Mo相量降低,810℃时完全溶解,钢的冲击功由32 J提高至61 J,当固溶温度由900℃增至1 050℃,随奥氏体晶粒增大,钢的冲击功由61 J降至26J。

关键词：马氏体时效钢00Ni14Cr3Mo3Ti 同溶处理奥氏体晶粒力学性能

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打造特色品牌与塑造医院形象

中国医院 2005年第8期9卷 47-48页

作者：李宝成孙晓军天津医科大学第二医院天津市河西区平江23号300211

打造医院特色品牌,树立医院形象是提升医院竞争力的需要。塑造医院自身形象,最终要靠雄厚的实力支撑,为此,医院要狠抓学科建设;强化特色;加大人才培养力度;要不断更新医疗设备,提高医院整体实力;充分利用大众传媒,营造有利于医院发展的... 详细信息

打造医院特色品牌,树立医院形象是提升医院竞争力的需要。塑造医院自身形象,最终要靠雄厚的实力支撑,为此,医院要狠抓学科建设;强化特色;加大人才培养力度;要不断更新医疗设备,提高医院整体实力;充分利用大众传媒,营造有利于医院发展的氛围。医院形象的塑造同时要靠全体人员的共同努力。

关键词：特色品牌医院形象市场竞争塑造医院竞争力自身形象学科建设人才培养医疗设备整体实力

Relative humidity-dependent evolution of molecular composition ofα-pinene secondary organic aerosol upon heterogeneous oxidation by hydroxyl radicals

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Journal of Environmental Sciences 2025年第2期148卷 210-220页

作者： Wei Wang Chenxi li Huayun Xiao Ziyue li Yue Zhao School of Environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Heterogeneous oxidation by gas-phase oxidants is an important chemical transformation pathway of secondary organic aerosol(SOA)and plays an important role in controlling the abundance,properties,as well as climate and health impacts of ***,our knowledge on this heterogeneous chemistry remains *** this study,the heterogeneous oxidation ofα-pinene ozonolysis SOA by hydroxyl(OH)radicals was investigated under both low and high relative humidity(RH)conditions,with an emphasis on the evolution of molecular composition of SOA and its RH *** is found that the heterogeneous oxidation of SOA at an OH exposure level equivalent to 12 hr of atmospheric aging leads to particle mass loss of 60%at 25%RH and 95%at 90%*** heterogeneous oxidation strongly changes the molecular composition of *** dimer-to-monomer signal ratios increase dramatically with rising OH exposure,in particular under high RH conditions,suggesting that aerosol water stimulates the reaction of monomers with OH radicals more than that of *** addition,the typical SOA tracer compounds such as pinic acid,pinonic acid,hydroxy pinonic acid and dimer esters(e.g.,C17H26O8 and C19H28O7)have lifetimes of several hours against heterogeneous OH oxidation under typical atmospheric conditions,which highlights the need for the consideration of their heterogeneous loss in the estimation of monoterpene SOA concentrations using tracer-based *** study sheds lights on the heterogeneous oxidation chemistry ofmonoterpene SOA andwould help to understand their evolution and impacts in the atmosphere.

关键词： Secondary organic aerosol(SOA) Heterogeneous oxidation Chemical transformation Molecular composition Aerosol water

Correlation between the rock mass properties and maximum horizontal stress:A case study of overcoring stress measurements

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 39-48页

作者： Peng li Meifeng Cai Shengjun Miao Yuan li Yu Wang Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyXuzhou 221116China

Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress *** investigate the correlation between the rock mass properties and maximum horizontal stress,the three-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring technique in nine mines in China were adopted,a newly defined characteristic parameter C_(ERP)was proposed as an indicator for evaluating the structural properties of rock masses,and a fuzzy relation matrix was established using the information distribution *** results indicate that both the vertical stress and horizontal stress exhibit a good linear growth relationship with *** is no remarkable correlation between the elastic modulus,Poisson's ratio and depth,and the distribution of data points is scattered and ***,there is no obvious relationship between the rock quality designation(RQD)and *** maximum horizontal stress σ_(H) is a function of rock properties,showing a certain linear relationship with the C_(ERP)at the same *** addition,the overall change trend of σ_(H) determined by the established fuzzy identification method is to increase with the increase of C_(ERP).The fuzzy identification method also demonstrates a relatively detailed local relationship betweenσ_H and C_(ERP),and the predicted curve rises in a fluctuating way,which is in accord well with the measured stress data.

关键词： overcoring stress measurements elastic modulus Poisson's ratio rock quality designation maximum horizontal stress fuzzy identification

半干旱区典型沙地生态环境演变特征及沙漠化防治建议

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中国沙漠 2024年第4期44卷 284-292页

作者：卢建男李玉强赵学勇李宝成王旭洋张蕊中国科学院西北生态环境资源研究院干旱区生态安全与可持续发展重点实验室/奈曼沙漠化研究站甘肃兰州730000 中国科学院大学北京100049 奈曼旗大柳树国有治沙林场内蒙古奈曼旗028300

沙地作为陆地生态系统重要组成,具有独特的结构和功能。中国北方半干旱、半湿润区的农牧交错带沙地生态环境经历了快速的人类活动正负向干扰过程,集中体现在“破坏利用”和“保护恢复利用”两个阶段。粗放式发展模式引发了一系列诸如土... 详细信息

沙地作为陆地生态系统重要组成,具有独特的结构和功能。中国北方半干旱、半湿润区的农牧交错带沙地生态环境经历了快速的人类活动正负向干扰过程,集中体现在“破坏利用”和“保护恢复利用”两个阶段。粗放式发展模式引发了一系列诸如土地沙漠化、水资源过度利用及生态失衡等问题。选取科尔沁沙地、毛乌素沙地、浑善达克沙地及呼伦贝尔沙地(四大沙地)作为研究对象,梳理了半干旱区典型沙地自然要素的地域分异特征、沙漠化土地时空演变过程及其驱动力、植被-土壤特征协同演变等方面的文献和研究成果;根据气候变化和人类活动影响下脆弱生态系统土地沙漠化态势及其治理现状认为,未来亟须在政策主导下的沙区人地关系协调发展和基于区域水量平衡的生态恢复及植被稳定性等方面加强研究,科学推进科尔沁、浑善达克两大沙地歼灭战等重点生态工程建设,促进半干旱沙区生态-经济-社会的可持续发展。

关键词：半干旱区沙地自然要素沙漠化生态治理

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热变形对ZK60镁合金组织及性能的影响

热加工工艺 2012年第20期41卷 8-10页

作者：王子田杨亚琴李保成韩保杰中北大学材料科学与工程学院山西太原030051

对ZK60镁合金进行了平面应变等温压缩试验,并对不同变形条件下压缩试样的微观组织、拉伸性能进行分析。结果表明,ZK60合金热变形后力学性能得到提高,尤其是塑性得到较大改善,伸长率最高达到38%,断口形貌由河流状变为韧窝状,这主要是由... 详细信息

对ZK60镁合金进行了平面应变等温压缩试验,并对不同变形条件下压缩试样的微观组织、拉伸性能进行分析。结果表明,ZK60合金热变形后力学性能得到提高,尤其是塑性得到较大改善,伸长率最高达到38%,断口形貌由河流状变为韧窝状,这主要是由于变形过程中产生动态再结晶,使晶粒明显细化;均匀态组织中个别未溶的共晶组织呈点状断续分布于晶界上,这些点状裂纹在变形过程中不易扩展还可能愈合;在300～380℃对均匀态ZK60合金进行平面压缩后,可获得较优的综合力学性能。

关键词： ZK60镁合金均匀化处理压缩变形组织力学性能

A Wind Tunnel Experimental Study on the Wake Characteristics of a Horizontal Axis Wind Turbine

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Journal of Thermal Science 2025年第1期34卷 145-158页

作者： GUO Xingduo li Yinran li Rennian MA Yulong WEI Kui College of Energy and Power Engineering Lanzhou University of TechnologyLanzhou 730050China Key Laboratory of Fluid Machinery and Systems Lanzhou 730050China Gansu Provincial Technology Centre for Wind Turbines Lanzhou 730050China

The characteristics of wind turbine wakes are influenced by multiple factors,including the atmospheric boundary layer(ABL)wind and wind turbine operating conditions(e.g.,tip speed ratio and yaw angle).In this study,two types of ABL winds with different velocity gradients and turbulence intensities are generated in a wind tunnel through configurations of spires,baffles,and various numbers of roughness elements.A wind turbine with a rotor diameter of 0.8 m and a hub height of 0.6 m is tested under varying tip speed ratios,yaw angles,and ABL wind *** results indicate that the streamwise velocity deficit in the near-wake region becomes more pronounced with an increase in the tip speed ratio,while the far-wake velocity deficit remains largely unaffected by changes in the tip speed *** the yaw angle increases,the wake deflection becomes more prominent and the wake narrows;the offset of the wake center at various downstream positions grows linearly,reaching a maximum value of approximately half the rotor ***,the turbulence level and influence range in the wake region are reduced when the turbine is *** ABL wind conditions,high turbulence intensity in the incoming flow accelerates wake recovery,and the Reynolds stress at different lateral positions tends to become consistent with increasing longitudinal ***,turbulence has a significant impact on the meandering characteristics of the wind turbine wake,with greater fluctuations in the wake center observed under higher turbulence ***,this study provides insights that could inform the optimal operation of wind farms.

关键词： horizontal axis wind turbine wind tunnel experiment wind turbine wake turbulence