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Acta Metallurgica Sinica(English Letters) 2020年第2期33卷 319-326页

作者： nan Xu ruo-nan feng Wen-feng Guo Qi-Ning Song Ye-feng Bao College of Mechanical and Electrical Engineering Hohai UniversityChangzhou 213022China

In this work,the influence of the Zener-Hollomon(Z)parameter on the microstructure and mechanical properties of copper subjected to friction stir welding(FSW)was *** N2 cooling was conducted to control the cooling rate after the *** obtained results demonstrate that the Z parameter was dependent on the tool rotation rate during the FSW,i.e.,a higher tool rotating rate resulted in a lower Z *** grain size in the stir zone decreased with the increase in the Z *** relationship between the yield strength and the Z parameter is established asσ0.2=σ0+*** relationship exhibited two different plots under the conditions of air cooling and liquid N2 *** at a similar Z parameter,a significant yield strength difference occurred because massive dislocations,which were caused by the prevention of the post-annealing effect,were maintained in the stir *** study suggests that the influence of the post-annealing effect should not be neglected when analyzing the relationship between the Z parameter,micro structure,and mechanical properties.

关键词： Copper Friction stir welding Microstructure Mechanical properties

Neuroprotective potential for mitigating ischemia-reperfusion-induced damage

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Neural Regeneration Research 2025年第8期20卷 2199-2217页

作者： Zi Ye Runqing Liu Hangxing Wang Aizhen Zuo Cen Jin nan Wang Huiqi Sun Luqian feng Hua Yang The Clinical Medical College Guizhou Medical UniversityGuiyangGuizhou ProvinceChina Division of Infectious Diseases Department of Internal MedicinePeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina School of Medical Imaging Guizhou Medical UniversityGuiyangGuizhou ProvinceChina Division of Gastroenterology First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina The Second Clinical Medical College Lanzhou UniversityLanzhouGansu ProvinceChina Department of Neurosurgery Affiliated Hospital of Guizhou Medical UniversityGuiyangGuizhou ProvinceChina

Reperfusion following cerebral ischemia causes both structural and functional damage to brain tissue and could aggravate a patient's condition;this phenomenon is known as cerebral ischemia-reperfusion *** studies have elucidated the neuroprotective role of the sirtuin protein family(Sirtuins)in modulating cerebral ischemia-reperfusion ***,the potential of utilizing it as a novel intervention target to influence the prognosis of cerebral ischemia-reperfusion injury requires additional *** this review,the origin and research progress of Sirtuins are summarized,suggesting the involvement of Sirtuins in diverse mechanisms that affect cerebral ischemia-reperfusion injury,including inflammation,oxidative stress,blood-brain barrier damage,apoptosis,pyroptosis,and *** therapeutic avenues related to Sirtuins that may improve the prognosis of cerebral ischemia-reperfusion injury were also investigated by modulating Sirtuins expression and affecting representative pathways,such as nuclear factor-kappa B signaling,oxidative stress mediated by adenosine monophosphate-activated protein kinase,and the forkhead box *** review also summarizes the potential of endogenous substances,such as RNA and hormones,drugs,dietary supplements,and emerging therapies that regulate Sirtuins *** review also reveals that regulating Sirtuins mitigates cerebral ischemia-reperfusion injury when combined with other risk *** Sirtuins show promise as a potential target for the treatment of cerebral ischemiareperfusion injury,most recent studies are based on rodent models with circadian rhythms that are distinct from those of humans,potentially influencing the efficacy of Sirtuinstargeting drug ***,this review provides new insights into the role of Sirtuins in the pathology and treatment of cerebral ischemia-reperfusion injury.

关键词： apoptosis autophagy blood-brain barrier dietary supplements drug hormones inflammation neuroprotection oxidative stress prognosis pyroptosis reperfusion injury risk factors RNA therapeutics

Hypoxia-preconditioned bone marrow-derived mesenchymal stem cells protect neurons from cardiac arrest-induced pyroptosis

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Neural Regeneration Research 2025年第4期20卷 1103-1123页

作者： Xiahong Tang nan Zheng Qingming Lin Yan You Zheng Gong Yangping Zhuang Jiali Wu Yu Wang Hanlin Huang Jun Ke feng Chen Shengli Clinical Medical College of Fujian Medical University Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Emergency Fujian Provincial HospitalFuzhouFujian ProvinceChina Fujian Provincial Key Laboratory of Emergency Medicine FuzhouFujian ProvinceChina The Second Department of Intensive Care Unit Fujian Provincial Hospital South BranchFuzhouFujian ProvinceChina

Cardiac arrest can lead to severe neurological impairment as a result of inflammation,mitochondrial dysfunction,and post-cardiopulmonary resuscitation neurological *** preconditioning has been shown to improve migration and survival of bone marrow–derived mesenchymal stem cells and reduce pyroptosis after cardiac arrest,but the specific mechanisms by which hypoxia-preconditioned bone marrow–derived mesenchymal stem cells protect against brain injury after cardiac arrest are *** this end,we established an in vitro co-culture model of bone marrow–derived mesenchymal stem cells and oxygen–glucose deprived primary neurons and found that hypoxic preconditioning enhanced the protective effect of bone marrow stromal stem cells against neuronal pyroptosis,possibly through inhibition of the MAPK and nuclear factor κB ***,we transplanted hypoxia-preconditioned bone marrow–derived mesenchymal stem cells into the lateral ventricle after the return of spontaneous circulation in an 8-minute cardiac arrest rat model induced by *** results showed that hypoxia-preconditioned bone marrow–derived mesenchymal stem cells significantly reduced cardiac arrest–induced neuronal pyroptosis,oxidative stress,and mitochondrial damage,whereas knockdown of the liver isoform of phosphofructokinase in bone marrow–derived mesenchymal stem cells inhibited these *** conclude,hypoxia-preconditioned bone marrow–derived mesenchymal stem cells offer a promising therapeutic approach for neuronal injury following cardiac arrest,and their beneficial effects are potentially associated with increased expression of the liver isoform of phosphofructokinase following hypoxic preconditioning.

关键词： bone marrow–derived mesenchymal stem cells cardiac arrest cardiac resuscitation hypoxic preconditioning liver isoform of phosphofructokinase mitochondria neuroinflammation oxidative stress pyroptosis reactive oxygen species

Understanding the local structure and thermophysical behavior of Mg-La liquid alloys via machine learning potential

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 439-449页

作者： Jia Zhao Taixi feng Guimin Lu National Engineering Research Center for Integrated Utilization of Salt Lake Resource East China University of Science and TechnologyShanghai 200237China Joint International Laboratory for Potassium and Lithium Strategic Resources East China University of Science and TechnologyShanghai 200237China

The local structure and thermophysical behavior of Mg-La liquid alloys were in-depth understood using deep potential molecular dynamic(DPMD) simulation driven via machine learning to promote the development of Mg-La alloys. The robustness of the trained deep potential(DP) model was thoroughly evaluated through several aspects, including root-mean-square errors(RMSEs), energy and force data, and structural information comparison results;the results indicate the carefully trained DP model is reliable. The component and temperature dependence of the local structure in the Mg-La liquid alloy was analyzed. The effect of Mg content in the system on the first coordination shell of the atomic pairs is the same as that of temperature. The pre-peak demonstrated in the structure factor indicates the presence of a medium-range ordered structure in the Mg-La liquid alloy, which is particularly pronounced in the 80at% Mg system and disappears at elevated temperatures. The density, self-diffusion coefficient, and shear viscosity for the Mg-La liquid alloy were predicted via DPMD simulation, the evolution patterns with Mg content and temperature were subsequently discussed, and a database was established accordingly. Finally, the mixing enthalpy and elemental activity of the Mg-La liquid alloy at 1200 K were reliably evaluated,which provides new guidance for related studies.

关键词： magnesium-lanthanum liquid alloys local structure macroscopic properties thermodynamic behavior deep potential mo-lecular dynamic simulation

Observation of acoustic hybrid topological phases induced by the p-d orbital interactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 132-139页

作者： Xiao Xiang feng Gao Yu-Gui Peng Peng Wu Zong-Lin Li Xue-feng Zhu School of Physics and Innovation Institute Huazhong University of Science and Technology

In spinless systems,growing attention has recently been attracted to synthetic gauge fields,which redefine the fundamental crystal symmetries by utilizing the projective algebraic ***,synthetic gauge fields have been commonly investigated in single orbital systems,and explorations on hybrid orbitals remain elusive in ***,we report the experimental observation of hybrid topological phases induced by hybrid synthetic gauge flux,which is formed by the interaction between p and d orbitals embedded in acoustic *** breaking the translation symmetries of Lxand/or Ly,we unambiguously demonstrate the first-order M?bius edge states and higher-order corner *** work establishes a platform for seeking exotic topological phases induced by hybrid-orbitals interactions and initializing the framework of hybrid-orbitalsrelated topological *** applications can be anticipated in scenarios such as high-quality sensing and robust wave trapping due to the stepwise energy distribution of the hybrid topological phase.

关键词： topological insulator synthetic gauge field projective symmetry corner states

抗菌压电材料:对细菌无选择性杀伤和不产生细菌耐药性

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中国组织工程研究 2025年第10期29卷 2105-2112页

作者：冯楠李运峰口腔疾病防治全国重点实验室国家口腔医学中心国家口腔疾病临床医学研究中心四川大学华西口腔医院口腔颌面外科四川省成都市610041

背景:压电材料可通过催化作用产生活性氧,通过多种途径来破坏细菌,而且不会导致细菌产生耐药性。这种不依赖抗生素的抗菌方式具有明显的优势,可以对细菌进行无差别的杀伤,为今后的抗菌策略提供了一种新思路。目的:文章主要总结了有关压... 详细信息

背景:压电材料可通过催化作用产生活性氧,通过多种途径来破坏细菌,而且不会导致细菌产生耐药性。这种不依赖抗生素的抗菌方式具有明显的优势,可以对细菌进行无差别的杀伤,为今后的抗菌策略提供了一种新思路。目的:文章主要总结了有关压电材料特性与抗菌机制,并讨论了部分压电材料在抗菌领域的研究现状。方法:在Pub Med、Web of Science、中国知网和万方数据库中,以“压电材料,压电催化,活性氧,抗菌,细菌感染,抗感染,耐药性”为中文检索词,以“piezoelectric materials,piezoelectricity,piezoelectric catalysis,piezocatalysis,reactive oxygen species,ROS,bacterial infection,antibacterial strategies,anti-infection,drug resistance,drug-resistant bacteria”为英文检索词。检索时间范围重点为2013年1月至2023年12月,通过阅读文题和摘要进行初步筛选;排除中英文重复性研究及内容不相关的文献,经文献质量评价后,最后纳入68篇文献进行综述。结果与结论:(1)压电材料是一类性质稳定的环境友好型材料,其大多数具有良好的生物相容性。(2)压电材料在压电效应过程中可催化产生大量活性氧,活性氧可通过细胞外氧化和细胞内氧化,破坏细菌的细胞膜、胞内蛋白质、酶以及核酸等物质,影响细菌的结构和功能,甚至导致细菌死亡从而实现抗菌。抗菌性能与催化生成活性氧速率相关,而催化速率与材料体系、形貌及外界条件等多种因素相关。(3)压电催化产生的活性氧对细菌不具备选择性,因此表现出广谱抗菌性,且这种抗菌方式不需要依赖抗菌药物,故不会引起细菌耐药性问题。(4)结合超声波无创、可控性与穿透性强等优点,未来压电材料作为耐药菌感染的辅助或替代治疗等具有重要价值和巨大潜力。(5)目前压电材料催化效率低下的难题限制了其在抗菌领域的应用,如何提高压电催化效率成为了学者们关注的焦点。

关键词：压电材料纳米材料压电效应压电催化活性氧抗菌治疗抗生素耐药性

ULTRASONIC INVESTIGATION OF BLOOD

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Chinese Journal of Acoustics 1989年第2期8卷 170-177页

作者： feng, ruo nanjing Univ Nanjing China

Ultrasonic biophysicists and physicians have continuously exhibited great interest in studying the ultrasonic properties of blood. It is shown that compressibility of red cell appears to be inversely proportional with its hemoglobin content. Among ultrasonic attenuation produced by red cell structure level in blood, absorption of red cell plays predominant role, viscous relative motion loss accounts for less than 15%, and cell scattering contribution is negligible. The coagulation process of blood is accompanied by significant change of sound parameters. The marked advantage has been found in test of blood coagulation process by using ultrasonic technique than the traditional viscous method. Blood coagulation causes sound attenuation, sound backscattering and nonlinearity parameter B/A to increase, but the attenuation frequency dependence hardly changes. All of these findings are of an important realistic significance for developing ultrasonic medicine.

关键词： Mathematical Models Transducers Applications Ultrasonic Waves Velocity Ultrasonics Applications

Image meshing via hierarchical optimization

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Frontiers of Information Technology & Electronic Engineering 2016年第1期17卷 32-40页

作者： Hao XIE ruo-feng TONG Institute of Artificial Intelligence Zhejiang University

Vector graphic, as a kind of geometric representation of raster images, has many advantages, e.g.,definition independence and editing facility. A popular way to convert raster images into vector graphics is image meshing, the aim of which is to find a mesh to represent an image as faithfully as possible. For traditional meshing algorithms, the crux of the problem resides mainly in the high non-linearity and non-smoothness of the ob jective,which makes it difficult to find a desirable optimal solution. To ameliorate this situation, we present a hierarchical optimization algorithm solving the problem from coarser levels to finer ones, providing initialization for each level with its coarser ascent. To further simplify the problem, the original non-convex problem is converted to a linear least squares one, and thus becomes convex, which makes the problem much easier to solve. A dictionary learning framework is used to combine geometry and topology elegantly. Then an alternating scheme is employed to solve both parts. Experiments show that our algorithm runs fast and achieves better results than existing ones for most images.

关键词： Image meshing, Hierarchical optimization, Convexification

CD147 deficiency in T cells prevents thymic involution by inhibiting the EMT process in TECs in the presence of TGFβ

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Cellular & Molecular Immunology 2021年第1期18卷 171-181页

作者： ruo Chen Ke Wang Zhuan feng Ming-Yang Zhang Jiao Wu Jie-Jie Geng Zhi-nan Chen Department of Cell Biology College of Life Science and TechnologyJinan UniversityGuangdongChina National Translational Science Center for Molecular Medicine&Department of Cell Biology Fourth Military Medical UniversityShaanxiChina

Thymic involution during aging is a major cause of decreased T-cell production and reduced ***,we show that the loss of CD147 on T cells prevents thymic senescence,resulting in slowed shrinkage of the thymus with age and increased production of naive T *** phenotype is the result of slowing of the epithelial-mesenchymal transition(EMT)process in thymic epithelial cells(TECs),which eventually leads to reduced adipocyte *** an in vitro coculture system,we found that TGFβ is an important factor in the EMT process in TECs and that it can reduce the expression of E-cadherin through p-5mad2/FoxC2 ***,CD147 on T cells can accelerate the decline in E-cadherin expression by interacting with Annexin A2 on *** the presence of TGFβ,Annexin A2 and E-cadherin colocalize on ***,CD147 on T cells competitively binds to Annexin A2 on TECs,leading to the isolation of ***,the isolated E-cadherin is easily phosphorylated by phosphorylated Src kinase,the phosphorylation of which was induced by TGFβ,and finally,p-E-cadherin is ***,in the thymus,the interaction between T ceils and TECs contributes to thymic involution with *** this study,we illuminate the mechanism underlying the triggering of the EMT process in TECs and show that inhibiting TGFβ and/or CD147 may serve as a strategy to hinder age-related thymic involution.

关键词： CD147 TGFβ thymic involution EMT

NIR photothermal enhancement to achieve high-efficiency nitrogen reduction to ammonia by polyoxometalates@Fe-polydopamine

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nano Research 2025年第1期18卷 118-128页

作者： Xiaofei Chen Lixin Wu feng Bai Key Laboratory for Special Functional Materials of Ministry of Education National&Local Joint Engineering Research Center for High-Efficiency Display and Lighting TechnologySchool of Nanoscience and Materials EngineeringHenan UniversityKaifeng 475004China State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China

The development of atmospheric pressure N_(2)reduction to NH_(3)is attracting much attention in green chemistry,yet it is still a challenge to obtain satisfactory activity under mild ***,an efficient near-infrared(NIR)photothermal catalysis reduction of N_(2)constitutes an occurrence is *** or without V-substitute polyoxometalates(POMs)loaded on the surface of Fechelated polydopamine(Fe-PDA)photothermal support through the electrostatic interactions,NIR photothermal catalysts POMs@Fe-PDA are *** induction of“FeV”cofactor facilitates electron transfer between V(V)/V(IV)&Fe(III)/Fe(II)and N_(2),thereby activating N_(2)*** synergy between the catalytic activity of V-POMs and the local NIR photothermal effect of Fe-PDA dramatically enhances N_(2)***,PMo_(10)V_(2)@Fe-PDA exhibits a significantly enhanced NH_(3)production rate of 181.1μmol·LN^(-1)with a turnover frequency of 1006.1 mmol·MN^(-1)·hN^(-1)under 808 nm NIR laser radiation,being the highest values reported at atmospheric *** expect that this work could provide an alternative approach for photothermal catalysis N_(2)reduction under mild conditions.

关键词： polyoxometalate near-infrared photothermal catalysis N_(2)reduction mild condition