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International Journal of Minerals,Metallurgy and Materials 2021年第1期28卷 131-141页

作者： gao-hui li li Zhou ling-yun Luo Xi-ming Wu Ning Guo State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China Shandong Provincial Key Laboratory of Special Welding Technology Harbin Institute of Technology(WeihaiWeihai)264209China

In this study, we used the stop-action technique to experimentally investigate the material flow and microstructural evolution of alclad 2A12-T4 aluminum alloy during refill friction stir spot *** are two material flow components, i.e., the inward-or outward-directed spiral flow on the horizontal plane and the upward-or downward-directed flow on the vertical *** the plunge stage, the flow of plasticized metal into the cavity is similar to that of a stack, whereby the upper layer is pushed upward by the lower *** the refill stage, this is process *** such, there is no obvious vertical plasticized metal flow between adjacent *** leads to the coarsening of S(Al2CuMg) in the thermo-mechanically affected zone and the diminishing of S in the stir *** dynamic recrystallization results in the formation of fine equiaxed grains in the stir zone, but this process becomes difficult in the thermo-mechanically affected zone due to the lower deformation rate and the pinning action of S precipitates on the dislocations and sub-grain boundaries, which leads to a high fraction of low-angle grain boundaries in this zone.

关键词： refill friction stir spot welding aluminum alloy material flow behavior precipitate evolution dislocation configuration

Effect of tool plunge depth on the microstructure and fracture behavior of refill friction stir spot welded AZ91 magnesium alloy joints

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International Journal of Minerals,Metallurgy and Materials 2021年第4期28卷 699-709页

作者： Hai-feng Zhang li Zhou Wen-lin li gao-hui li Yi-tang Tang Ning Guo Ji-cai Feng Shandong Provincial Key Laboratory of Special Welding Technology Harbin Institute of Technology at WeihaiWeihai 264209China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China

We used refill friction stir spot welding(RFSSW)to join 2-mm-thick AZ91D-H24 magnesium alloy sheets,and we investigated in detail the effect of tool plunge depth on the microstructure and fracture behavior of the joints.A sound joint surface can be obtained using plunge depths of 2.0 and 2.5 *** depth was found to significantly affect the height of the hook,with greater plunge depths corresponding to more severe upward bending of the hook,which compromised the tensile-shear properties of the *** hardness reached a minimum at the thermo-mechanically affected zone due to the precipitation phases of this zone as it dissolved into theα-matrix during the welding *** fracture modes of RFSSW joints can be divided into three types:shear fracture,plug fracture,and shear–plug *** these,the joint with a shear–plug fracture exhibited the best tensile-shear load of 6400 N.

关键词： refill friction stir spot welding AZ91 magnesium alloy microstructure fracture behavior

Difference schemes on non-uniform mesh and their application

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Progress in Natural Science:Materials International 2004年第10期14卷 8-14页

作者： MA Yanwen ,gao hui,FU Dexun and li Xinliang (Laboratory of Nonlinear Mechanics,Institute of Mechanics,Chinese Academy of Sciences,Beijing100080,China) Chinese Acad Sci Inst Mech Lab Nonlinear Mech Beijing 100080 Peoples R China

High order accurate schemes are needed to simulate the multi-scale complex flow fields to get fine structures in simula-tion of the complex flows with large gradient of fluid parameters near the wall,and schemes on non-uniform mesh are desirable for many CFD(computational fluid dynamics)*** construction methods of difference approximations and several difference approxima-tions on non-uniform mesh are *** accuracy of the methods and the influence of stretch ratio of the neighbor mesh increment on accuracy are *** comments on these methods are given,and comparison of the accuracy of the results obtained by schemes based on both non-uniform mesh and coordinate transformation is made,and some numerical examples with non-uniform mesh are present-ed.

关键词： scheme on non-uniform mesh high order accurate scheme compact difference approximation

Differences and Correlations of Morphological and Hemodynamic Parameters between Anterior Circulation Bifurcation and Side-wall Aneurysms

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Current Medical Science 2024年第2期44卷 391-398页

作者： Kai-kai GUO Chang-ya liU gao-hui li Jian-ping XIANG Xiao-chang LENG Yi-ke CAI Xue-bin HU Department of Neurosurgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Department of Emergency Longhua HospitalShanghai University of Traditional Chinese MedicineShanghai 200032China Artery Flow Technology Co. Ltd.Hangzhou 310051China

Objective:The objective of this research was to explore the difference and correlation of the morphological and hemodynamic features between sidewall and bifurcation aneurysms in anterior circulation arteries,utilizing computational fluid dynamics as a tool for ***:In line with the designated inclusion criteria,this study covered 160 aneurysms identified in 131 patients who received treatment at Union Hospital of Tongji Medical College,Huazhong University of Science and Technology,China,from January 2021 to September *** follow-up digital subtraction angiography(DSA)data,these cases were classified into two distinct groups:the sidewall aneurysm group and the bifurcation aneurysm *** and hemodynamic parameters in the immediate preoperative period were meticulously calculated and examined in both groups using a three-dimensional DSA reconstruction ***:No significant differences were found in the morphological or hemodynamic parameters of bifurcation aneurysms at varied locations within the anterior ***,pronounced differences were identified between sidewall and bifurcation aneurysms in terms of morphological parameters such as the diameter of the parent vessel(Dvessel),inflow angle(θF),and size ratio(SR),as well as the hemodynamic parameter of inflow concentration index(ICI)(P0.5,P<0.001).Conclusions:The significant differences in certain morphological and hemodynamic parameters between sidewall and bifurcation aneurysms emphasize the importance to contemplate variances in threshold values for these parameters when evaluating the risk of rupture in anterior circulation *** it is a bifurcation or sidewall aneurysm,these disparities should be *** morphological parameter SR has the potential to be a val

关键词： sidewall bifurcation unruptured aneurysms computational fluid dynamics

Decoding the nexus:branched-chain amino acids and their connection with sleep,circadian rhythms,and cardiometabolic health

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Neural Regeneration Research 2025年第5期20卷 1350-1363页

作者： hui li Laurent Seugnet Department of Neurology Xijing HospitalXi’anShaanxi ProvinceChina Centre de Recherche en Neurosciences de Lyon Integrated Physiology of the Brain Arousal Systems(WAKING)UniversitéClaude Bernard Lyon 1INSERM U1028CNRS UMR 5292BronFrance

The sleep-wake cycle stands as an integrative process essential for sustaining optimal brain function and,either directly or indirectly,overall body health,encompassing metabolic and cardiovascular *** the heightened metabolic activity of the brain,there exists a considerable demand for nutrients in comparison to other *** these,the branched-chain amino acids,comprising leucine,isoleucine,and valine,display distinctive significance,from their contribution to protein structure to their involvement in overall metabolism,especially in cerebral *** the first amino acids that are released into circulation post-food intake,branched-chain amino acids assume a pivotal role in the regulation of protein synthesis,modulating insulin secretion and the amino acid sensing pathway of target of ***-chain amino acids are key players in influencing the brain's uptake of monoamine precursors,competing for a shared *** their involvement in protein synthesis,these amino acids contribute to the metabolic cycles ofγ-aminobutyric acid and glutamate,as well as energy ***,they impact GABAergic neurons and the excitation/inhibition *** rhythmicity of branchedchain amino acids in plasma concentrations,observed over a 24-hour cycle and conserved in rodent models,is under circadian clock *** mechanisms underlying those rhythms and the physiological consequences of their disruption are not fully *** sleep,obesity,diabetes,and cardiovascular diseases can elevate branched-chain amino acid concentrations or modify their oscillatory *** mechanisms driving these effects are currently the focal point of ongoing research efforts,since normalizing branched-chain amino acid levels has the ability to alleviate the severity of these *** this context,the Drosophila model,though underutilized,holds promise in shedding new light on these *** findings indicate its po

关键词： branched-chain amino acids cardiovascular health circadian clock drosophila insulin metabolism sleep γ-aminobutyric acid

Bulging Performance and Quality Control of Aluminum Alloy Tailor-welded Overlapping Sheets Based on Interface Friction

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 258-264页

作者： gao Tiejun gao Bowen li Weijie ZHANG Jiabin College of Aerospace Engineering Shenyang Aerospace UniversityShenyang 110136China Shenyang Aerospace Xinguang Group Co.L td. Shenyang 110043China

In order to solve the problem of poor formability caused by different materials and properties in the process of tailor-welded sheets forming,a forming method was proposed to change the stress state of tailor-welded sheets by covering the tailor-welded sheets with better plastic properties overlapping *** the same time,the interface friction effect between the overlapping and tailor-welded sheets was utilized to control the stress magnitude and further improve the formability and quality of the tailor-welded *** this work,the bulging process of the tailor-welded overlapping sheets was taken as the research *** alloy tailor-welded overlapping sheets bulging specimens were studied by a combination of finite element analysis and experimental *** results show that the appropriate use of interface friction between tailor-welded and overlapping sheets can improve the formability of tailor-welded sheets and control the flow of weld seam to improve the forming *** increasing the interface friction coefficient on the side of tailor-welded sheets with higher strength and decreasing that on the side of tailor-welded sheets with lower strength,the deformation of the tailor-welded sheets are more uniform,the offset of the weld seam is minimal,the limit bulging height is maximal,and the forming quality is optimal.

关键词： tailor-welded sheets overlapping sheet bulging interface friction weld seam stress

Small extracellular vesicles derived from human induced pluripotent stem cell-differentiated neural progenitor cells mitigate retinal ganglion cell degeneration in a mouse model of optic nerve injury

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Neural Regeneration Research 2025年第2期20卷 587-597页

作者： Tong li hui-Min Xing Hai-Dong Qian Qiao gao Sheng-Lan Xu Hua Ma Zai-Long Chi State Key Laboratory of Ophthalmology Optometry and Visual ScienceEye HospitalWenzhou Medical UniversityWenzhouZhejiang ProvinceChina National Clinical Research Center for Ocular Diseases Eye HospitalWenzhou Medical UniversityWenzhouZhejiang ProvinceChina

Several studies have found that transplantation of neural progenitor cells(NPCs)promotes the survival of injured ***,a poor integration rate and high risk of tumorigenicity after cell transplantation limits their clinical *** extracellular vesicles(sEVs)contain bioactive molecules for neuronal protection and *** studies have shown that stem/progenitor cell-derived sEVs can promote neuronal survival and recovery of neurological function in neurodegenerative eye diseases and other eye *** this study,we intravitreally transplanted sEVs derived from human induced pluripotent stem cells(hiPSCs)and hiPSCs-differentiated NPCs(hiPSC-NPC)in a mouse model of optic nerve *** results show that these intravitreally injected sEVs were ingested by retinal cells,especially those localized in the ganglion cell *** with hiPSC-NPC-derived sEVs mitigated optic nerve crush-induced retinal ganglion cell degeneration,and regulated the retinal microenvironment by inhibiting excessive activation of *** analysis further revealed that hiPSC-NPC derived sEVs transported neuroprotective and anti-inflammatory miRNA cargos to target cells,which had protective effects on RGCs after optic nerve *** findings suggest that sEVs derived from hiPSC-NPC are a promising cell-free therapeutic strategy for optic neuropathy.

关键词： exosome miRNA neural progenitor cell neurodegeneration neuroinflammation neuroprotection optic nerve crush optic neuropathy retinal ganglion cell small extracellular vesicles

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自噬与糖尿病肾病相关性研究进展

国际药学研究杂志 2016年第5期43卷 844-848,857页

作者：郑元慧高丽辉李玲昆明医科大学生物医学工程研究中心昆明650500

自噬是细胞为应对内外环境压力变化而出现的一种正常反应,是细胞内物质成分被溶酶体降解的过程。近年来研究发现,自噬在糖尿病肾病(DN)的发生发展中起着重要作用,是DN治疗的潜在靶点,与肾足细胞的生长发育和生理病理活动密切相关,是一... 详细信息

自噬是细胞为应对内外环境压力变化而出现的一种正常反应,是细胞内物质成分被溶酶体降解的过程。近年来研究发现,自噬在糖尿病肾病(DN)的发生发展中起着重要作用,是DN治疗的潜在靶点,与肾足细胞的生长发育和生理病理活动密切相关,是一种细胞的自我保护机制,调控自噬相关信号通路可影响DN发生发展。因此,本文就DN的发病机制、自噬在肾固有细胞中的作用以及调控自噬相关信号通路对糖尿病肾病发生发展的影响等方面进行综述。

关键词：糖尿病肾病自噬通路肾脏足细胞

Local magnetic moment oscillation around an Anderson impurity on graphene

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 192-201页

作者： Shuai li Zhen Ma Jin-Hua gao School of Science Hebei University of Science and Technology School of Electronics and Information Zhengzhou University of Light Industry School of Physics and Wuhan National High Magnetic Field Center Huazhong University of Science and Technology

We theoretically investigate the spin resolved Friedel oscillation （FO） and quasiparticle interference （QPI） in graphene induced by an Anderson *** the impurity becomes magnetic,the resulted FO becomes spin dependent,which gives rise to a local magnetic moment oscillation with an envelop decaying as r-2in real space in the doping ***,at half filling,the electron density and local magnetic moment will not oscillate but decay as *** spin resolved FO has both sublattice and spin ***,the local magnetic moment decay at half filling only occurs at one sublattice of graphene,which is quite like the phenomenon observed in the STM experiment (***ález-Herrero et al.,Science 352,437 （2016）).We further give an analytic formula about such spin dependent FO based on the stationary phase ***,we study the interference of quasiparticles around the magnetic impurity by calculating the spin dependent Fourier-transformed local density of states （FT-LDOS）.Our work gives a comprehensive understanding about the local magnetic moment oscillation around an Anderson impurity on graphene.

关键词： Friedel oscillation local magnetic moment graphene Anderson impurity

Mechanisms of improvement of left ventricle remodeling by transplanting two kinds of autologous bone marrow stem cells in pigs

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Chinese Medical Journal 2008年第23期121卷 2403-2409页

作者： li Shu-ren QI Xiao-yong HU Fu-li ZHANG Jian-qing WANG Tian-hong DANG Yi MENG Cun-liang liU hui-liang li Ying-xiao WU Di DONG Jie XUN li-ying gao li-hui JIN Fu-chang Department of Cardiology People's Hospital of Hebei Province Shijiazhuang Hebei 050051 China

Background The necrosis of a large number of myocardial cells after acute myocardial infarction （AMI） results in a decrease of cardiac function and ventricle remodeling. Stem cell transplantation could improve cardiac function after AMI, but the involving mechanisms have not been completely understood. The present study aimed to investigate the effects of transplantation of autologous bone marrow mononuclear cells （BM-MNC） and mesenchymal stem cells （MSCs） via the coronary artery on the ventricle remodeling after AMI as well as the mechanisms of the effects of transplantation of different stem cells on ventricle remodeling. Methods A total of 36 male pigs were enrolled in this study, which were divided into 4 groups： control group, simple infarct model group, BM-MNC transplantation group, and MSCs transplantation group. At 90 minutes when a miniature porcine model with AMI was established, transplantation of autologous BM-MNC （（4.7±1.7）×10^7） and MSCs （（6.2±1.6）×10^5） was performed in the coronary artery via a catheter. Ultrasound, electron microscope, immunohistochemical examination and real time reverse transcriptase-pelymerase chain reaction were used respectively to observe cardiac functions, counts of blood vessels of cardiac muscle, cardiac muscle nuclear factor （NF）-κB, myocardial cell apoptosis, and the expression of the mRNA of vascular endothelial growth factor （VEGF） and basic fibroblast growth factor （bFGF） in cardiac muscles. Multivariate Logistic regression was used to analyze the correlation factors of left ventricular end-diastolic diameter （EDD）. Results The number of blood vessels in the infarct zone and around its border in the BM-MNC transplantation group was more than those in the infarct model group and MSCs group （P=0.0001） and there was less myocardial cell apoptosis in the stem cell transplantation group than that in the infarct model group （all P 〈0.01）. The positive rate of NF-κB in the stem cell transplantation group was lower than th

关键词： bone marrow mononuclear cell bone marrow mesenchymal stem cell cellular transplantation acute myocardial infarction ventricle remodeling