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Human-induced pluripotent stem cell-derived neural stem cell exosomes improve blood-brain barrier function after intracerebral hemorrhage by activating astrocytes via PI3k.Ak./MCP-1 axis

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Neural Regeneration Research 2025年第2期20卷 518-532页

作者： Conglin Wang Fangyuan Cheng Zhaoli Han bo Yan Pan Liao Zhenyu Yin Xintong Ge Dai Li Rongrong Zhong Qiang Liu Fanglian Chen Ping Lei Department of Geriatrics Tianjin Medical University General HospitalTianjinChina School of Medicine Nankai UniversityTianjinChina Tianjin Neurological Institute TianjinChina

Cerebral edema caused by blood-brain barrier injury after intracerebral hemorrhage is an important factor leading to poor ***-induced pluripotent stem cell-derived neural stem cell exosomes(hiPSC-NSC-Exos)have shown potential for brain injury repair in central nervous system *** this study,we explored the impact of hiPSC-NSC-Exos on blood-brain barrier preservation and the underlying *** results indicated that intranasal delivery of hiPSC-NSC-Exos mitigated neurological deficits,enhanced blood-brain barrier integrity,and reduced leuk.cyte infiltration in a mouse model of intracerebral ***,hiPSC-NSC-Exos decreased immune cell infiltration,activated astrocytes,and decreased the secretion of inflammatory cytokines lik. monocyte chemoattractant protein-1,macrophage inflammatory protein-1α,and tumor necrosis factor-αpost-intracerebral hemorrhage,thereby improving the inflammatory *** sequencing indicated that hiPSC-NSC-Exo activated the PI3k.Ak. signaling pathway in astrocytes and decreased monocyte chemoattractant protein-1 secretion,thereby improving blood-brain barrier *** with the PI3k.Ak. inhibitor LY294002 or the monocyte chemoattractant protein-1 neutralizing agent C1142 abolished these *** summary,our findings suggest that hiPSC-NSC-Exos maintains blood-brain barrier integrity,in part by downregulating monocyte chemoattractant protein-1 secretion through activation of the PI3k.Ak. signaling pathway in astrocytes.

关键词： Ak. astrocyte blood-brain barrier cerebral edema exosomes human-induced pluripotent stem cells intracerebral hemorrhage neural stem cells neuroinflammation PI3k

Processing effects on the magnetic and mechanical properties of FeCoNiAl_(0.2)Si_(0.2) high entropy alloy

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International Journal of Minerals,Metallurgy and Materials 2013年第6期20卷 549-555页

作者： Ting-ting Zuo Song-bo Ren Peter k. Liaw Yong Zhang State k.y Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing Hangk. Engine Control System Science & Technology Co. Ltd. Department of Materials Science and Engineering The University of Tennessee

High entropy alloys with the composition of FeCoNiA10.2Si0.2 were prepared by arc melting and induction melting, denoted by A1 and A2, respectively. The samples prepared by these two techniques have a face-centered cubic （FCC） phase structure and a typical dendrite morphology. The tensile yield strength and maximum strength of A2 samples are about 280 and 632 MPa, respectively. Moreover~ the elongation can reach 41.7%. These two alloys prepared by the different methods possess the similar magnetic properties. The saturation magnetization and coercivity can reach 1.151 T and 1400 A/m for A1 samples and 1.015 T and 1431 A/m for A2 samples, respectively. Phases in A2 samples do not change, which are heat treated at different temperatures, then quenched in water. Only the sample, which is heat treated at 600~C for 3 h and then furnace cooled, has a new phase precipitated. Besides, the coercivity decreases obviously at this temperature. Cold rolling and the subsequent heat treatment cannot improve the magnetic properties effectively. However, cold rolling plays an important role in improving the strength.

关键词： high entropy alloys magnetic properties mechanical properties heat treatment

Actinide-embedded gold superatom models： Electronic structure, spectroscopic properties, and applications in surface-enhanced Raman scattering

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Nano Research 2016年第3期9卷 622-632页

作者： Yang Gao bo Wang Yanyu Lei boon k. Teo Zhigang Wang Institute of Atomic and Molecular Physics Jilin University Changchun 130012 China Jilin Provincial k.y Laboratory of AppliedAtomic and Molecular Spectroscopy Jilin University Changchun 130012 China College of Chemistry and Molecular Engineering Peking University Beijing 100871 China College of Chemistry and Chemical Engineering Kiamen University Xiamen 361005 China Beijing Computational Science Research Center Beijing 100084 China

Actinide elements encaged in a superatomic cluster can exhibit unique properties due to their hyperactive valence electrons. Herein, the electronic and spectroscopic properties of Th@Au14 are predicted and compared with that of the isoelectronic entities [Ac@Au14]- and [Pa@Au14]＋ using density functional theory. The calculation results indicate that these clusters all adopt a closed- shell superatomic 18-electron configuration of the 1S21p61D10 Jellium state. The absorption spectrum of Th@Au14 can be interpreted by the Jelliumatic orbital model. In addition, calculated spectra of pyridine-Th@Au14 complexes in the blue laser band exhibit strong peak. attributable to charge transfer （CT） from the metal to the pyridine molecule. These charge-transfer bands lead to a resonant surface-enhanced Raman scattering （SERS） enhancement of -104. This work.suggests a basis for designing and synthesizing SERS substrate materials based on actinide-embedded gold superatom models.

关键词： actinide element DFT calculation gold nanoparticle superatomic orbital surface-enhanced Ramanscattering

Development of an Anthropomorphic Robotic Arm and Hand for Interactive Humanoids

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Journal of Bionic Engineering 2012年第2期9卷 133-142页

作者： Jamie k. Paik.Bu Hyun Shin Young-bong Bang Young-bo Shim The Institute of Mechanical Engineering EPFL STI I G M UPPAIK BM 4118 （Bdtiment BM） Station 17 Switzerland Department of Mechanical Engineering Hanbat University Daejeon 305-719 South Korea Advanced Institutes of Convergence Technology Seoul National University Suwon-si Gyeonggi-do 443-270 South Korea Mechatronics and Manufacturing Technology Center Samsung Electronics Co Suwon-si Gyeonggi-do 443-742 South Korea

Humanoid robots are designed and built to mimic human form and movement. Ultimately, they are meant to resemble the size and physical abilities of a human in order to function in human-oriented environments and to work.autonomously but to pose no physical threat to humans. Here, a humanoid robot that resembles a human in appearance and movement is built using powerful actuators paired with gear trains, joint mechanisms, and motor drivers that are all encased in a pack.ge no larger than that of the human physique. In this paper, we propose the construction of a humanoid-applicable anthropomorphic 7-DoF arm complete with an 8-DoF hand. The novel mechanical design of this humanoid ann mak.s it sufficiently compact to be compatible with currently available narrating-model humanoids, and to be sufficiently powerful and flexible to be functional; the number of degrees of freedom endowed in this robotic arm is sufficient for executing a wide range of task., including dexterous hand movements. The developed humanoid arm and hand are capable of sensing and interpreting incoming external force using the motor in each joint current without conventional torque sensors. The humanoid ann adopts an algorithm to avoid obstacles and the dexterous hand is capable of grasping objects. The developed robotic ann is suitable for use in an interactive humanoid robot.

关键词： humanoid arm humanoid hand human robot interaction safe robot arm and torque sensing

On stress-induced voltage hysteresis in lithium ion batteries:Impacts of surface effects and interparticle compression

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Science China(Technological Sciences) 2019年第8期62卷 1357-1364页

作者： JIN ChuanJian LI HaoLiang SONG YiCheng LU bo SOH A. k. ZHANG JunQian Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China Department of Mechanics Shanghai University Shanghai 200444 China Shanghai k.y Laboratory of Mechanics in Energy Engineering Shanghai University Shanghai 200444 China School of Engineering Monash University Sunway Campus Bandar Sunday 47500 Malaysia

Application of silicon in high capacity electrodes of lithium ion battery suffers from stress effects and, in turn, affects voltage performance of battery. This paper established a reaction-diffusion-stress coupled model and investigated the stress induced voltage hysteresis with consideration of diffusion induced stress, surface effects and interparticle compression. It was found stress and stress induced voltage hysteresis depended on particle size. In big particles, diffusion induced stress is dominant and leads to significant hysteresis in both stress and voltage, indicating energy dissipation due to stress effects. In small particles, e.g.,radius of dozens nanometers, diffusion induced stress was negligible while surface effects played dominant role, leading to nearly vanished voltage hysteresis shifting away from equilibrium potential. According to calculation, particle sizes around 100 nm are appropriate choice for electrode design as both diffusion induced stress and surface effects are insignificant. Finally,interparticle compression pushed the stress hysteresis to compressive side and led to early termination of lithiation at cut-off voltage. Denser electrode would enhance this effect. It indicated that there must be a limit of mixing ratio of silicon because higher interparticle compressive stress due to more introduced silicon would impede the battery from fully charged.

关键词： lithium ion battery voltage hysteresis stress surface effect interparticle compression

Laboratory investigation of the anisotropic confinement-dependent brittle-ductile transition of a Utah coal

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International Journal of Mining Science and Technology 2021年第1期31卷 51-57页

作者： bo-Hyun k.m Mark.k.Larson Mine Safety Branch CDC/NIOSH/SMRDSpokaneWA 99207USA

This paper was developed as part of an effort by the National Institute for Occupational Safety and Health(NIOSH)to identify risk.factors associated with bumps in the prevention of fatalities and accidents in highly stressed,bump-prone ground *** of failure mechanism with increasing confinement,from extensional-to shear-dominated failure,are widely observed in the rupture of intact specimens at the laboratory scale and in rock.*** the previous analysis conducted in 2018,both unconfined and triaxial compressive tests were conducted to investigate the strength characteristics of some specimens of a Utah coal,including the spalling limits,the ratio of apparent unconfined compressive strength(AUCS)to unconfined compressive strength(UCS),the damage characteristics,and the postyield *** mechanical characteristics were found to be strongly anisotropic as a function of the orientation of the cleats relative to the loading ***,the transition from extensional to shear failure at the given confinements was not clearly *** this study,a total of 20 specimens were additionally prepared from the same coal sample used in the previous study and then tested under both unconfined and triaxial compressive *** different confining stresses are used as analogs for different width-to-height(W/H)ratios of pillar *** the W/H ratios of the specimens were not directly considered during testing,the equivalent W/H ratios of a pillar as a function of the confining stresses were estimated using an existing empirical *** to this relationship,theW/H atwhich in-situ pillar behavior would be expected to transition from brittle to ductile is identified.

关键词： Bump-prone ground conditions A Utah coal Anisotropic Equivalent W/H ratios of a pillar

Development of a fault-rupture environment in 3D: A numerical tool for examining the mechanical impact of a fault on underground excavations

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International Journal of Mining Science and Technology 2019年第1期29卷 105-111页

作者： bo-Hyun k.m Mark.k.Larson Spokane Mining Research Division CDC/NIOSH

While faults are commonly simulated as a single planar or non-planar interface for a safety or stability analysis in underground mining excavation, the real 3D structure of a fault is often very complex, with different branches that reactivate at different times. Furthermore, these branches are zones of nonzero thick.ess where material continuously undergoes damage even during interseismic periods. In this study, the initiation and the initial evolution of a strik.-slip fault was modeled using the FLAC3D software program. The initial and boundary conditions are simplified, and mimic the Riedel shear experiment and the constitutive model in the literature. The FLAC3D model successfully replicates and creates the 3D fault zone as a strik.-slip type structure in the entire thick.ess of the model. The strik.-slip fault structure and normal displacement result in the formation of valleys in the model. Three panels of a longwall excavation are virtually placed and excavated beneath a main valley. The characteristics of stored and dissipated energy associated with the panel excavations are examined and observed at different stages of shear strain in the fault to evaluate bump potential. Depending on the shear strain in the fault, the energy characteristics adjacent to the longwall panels present different degrees of bump potential, which is not possible to capture by conventional fault simulation using an interface.

关键词： 3D fault zone Strik.-slip fault FLAC3D Bump potential Energy characteristics

Estimating emissions of HCFC-22 and CFC-11 in China by atmospheric observations and inverse modeling

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Science China Chemistry 2012年第10期55卷 2233-2241页

作者： AN XingQin HENNE Stephan YAO bo VOLLMER Martin k. ZHOU LingXi LI Yan Chinese Academy of Meteorological Sciences China Meteorological AdministrationBeijing 100081China Empa Swiss Federal Laboratories for Materials Testing and ResearchAir Pollution and Environmental TechnologyDubendorf Switzerland

This paper presents the estimation of Chinese emissions of HCFC-22 and CFC-11 in 2009 by an inverse modeling method based on in-situ measurement data from the Shangdianzi Global Atmosphere Watch (GAW) Regional Station (SDZ) and atmospheric transport simulations. After inversion (a-posteriori) estimates of the Chinese emissions in 2009 increased by 6.6% for HCFC-22 from 91.7 (± 83.6) to 98.3 (± 47.4) k./yr and by 22.5% for CFC-11 from 13 (±12.6) to 15.8 (±7.2) k./yr compared to an a-priori emission. While the model simulation with a-priori emissions already captured the main features of the observed variability at the measurement site, the model performance (in terms of correlation and mean-square-error) improved using a-posteriori emissions. The inversion reduced the root-mean-square (RMS) error by 4% and 10% for HCFC-22 and CFC-11, respectively.

关键词： FLEXPART model inversion modeling method emissions HCFC-22 and CFC-11 China

Bio-inspired tetracarbene compounds as a new family of energy saving catalysts

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Journal of Energy Chemistry 2023年第4期79卷 559-561页

作者： bo Zhang Fritz E.k.hn CAS k.y Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina' University of Chinese Academy of Science Beijing 100049China Molecular Catalysis Catalysis Research Center and Department of ChemistrySchool of Natural SciencesTechnical University of MunichLichtenbergstr 485748 Garching bei MünchenGermany

Efficient use of energy is a pressing *** of chemical processes is currently an important target for energy *** chemical processes are independent of pathways with respect to the final energy output or consumption,the application of catalysts can reduce involved activation energies considerably and therefore save large amounts of energy.

关键词： Catalysis Iron Carbenes Multidentate ligands