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FK506 contributes to peripheral nerve regeneration by inhibiting neuroinflammatory responses and promoting neuron survival

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Neural Regeneration Research 2025年第7期20卷 2108-2115页

作者： Yuhui Kou Zongxue Jin Yusong Yuan Bo Ma Wenyong Xie na Han Department of Trauma and Orthopedics Peking University People’s HospitalBeijingChina national Center for Trauma Medicine Peking University People’s HospitalBeijingChina Key Laboratory of Trauma and Neural Regeneration(Peking University) Ministry of EducationBeijingChina Trauma Medicine Center Peking University People’s HospitalBeijingChina Department of Orthopedics China-Japan Friendship HospitalBeijingChina

FK506(tacrolimus)is a systemic immunosuppressant approved by the *** and Drug ***506 has been shown to promote peripheral nerve regeneration,however,its precise mechanism of action and its pathways remain *** this study,we established a rat model of sciatic nerve injury and found that FK506 improved the morphology of the injured sciatic nerve,increased the numbers of motor and sensory neurons,reduced inflammatory responses,markedly improved the conduction function of the injured nerve,and promoted motor function *** findings suggest that FK506 promotes peripheral nerve structure recovery and functional regeneration by reducing the intensity of inflammation after neuronal injury and increasing the number of surviving neurons.

关键词： FK506 inflammation motor neurons nerve regeneration neuron peripheral nerve injury sensory neurons

Design of Floating Mass Type Piezoelectric Actuator for Implantable Middle Ear Hearing Devices

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Chinese Journal of Mechanical Engineering 2009年第2期22卷 221-226页

作者： LIU Houguang ta na MING Xiaofeng RAO Zhushi state Key Laboratory of Mechanical system and Vibrations Shanghai Jiao Tong University Shanghai 200240 China

To overcome some of the problems inherent in conventional heating aids such as low gain at high fi＇equencies due to acoustic feedback, discomfort in occlusion of the extemal ear canal and so on, implantable middle ear hearing devices （IMEHDs） have been developed over the past two decades. For such kinds of IMEHDs, this paper presents the design of a floating mass piezoelectric actuator using a PMN-30%PT stack as a new type of vibrator. The proposed piezoelectric actuator consists of only three components of a piezoelectric stack, a metal case and a clamp. For the purpose of aiding the design of this actuator, a coupling biomechanics model of human middle ear and the piezoelectric actuator was constructed. This model was built based on a complete set of computerized tomography section images of a healthy volunteer＇s left ear by reverse engineering technology. The validity of this model was confirmed by comparing the motion of the tympanic membrane and stapes footplate obtained by this model with published experimental measurements on human temporal bones. It is shown that the designed actuator can be implanted on the incus long process by a simple surgical operation, and the stapes footplate displacement by its excitation at 10.5 V root-mean-square（RMs） voltage was equivalent to that from acoustic stimulation at 100 dB sound pressure level（sPL）, which is adequate stimulation to the ossicular chain. The corresponding power consumption is 0.04 mW per volt of excitation at 1 kHz, which is low enough for the transducer to be used in an implantable middle ear device.

关键词： piezoelectric actuator implantable middle ear hearing device floating mass fmite element model

Kinetic modeling of high-temperature oxidation of pure Mg

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Journal of Magnesium and Alloys 2020年第3期8卷 819-831页

作者： sa Ma Fangzhou Xing na ta Lijun Zhang state Key Laboratory of Powder Metallurgy Central South UniversityChangshaHunan 410083P.R.China Max-Planck-Institut fiir Eisenforschung GmbH Max-Planck-Straβe 140237DusseldorfGermany

A variety of experimental tracer diffusivities of Mg and O in magnesium oxide available in the literature were first *** mobilities including bulk and short-circuit diffusion of Mg and O were then obtained by means of the CALPHAD(Calculation of Phase Diagram)***,the diffusion-controlled kinetic model of oxidation in a gas-MgO-Mg environment was developed based on the moving boundary model and Fick's law,coupling with the modified thermodynamic description of MgO.A mathematical expression for parabolic rate constant kp of the oxide scale was derived for magnesia and correlated with the thermodynamic and diffusion kinetic *** evaluated kp results were in line with the experimental ***,the oxidation process of pure magnesium at 673 K was model-predicted,and the predicted evolution of the oxide thicknesses agreed very well with the experimental *** was indicated that the grain boundaries diffusion of magnesium cations predominated the high temperature oxidation process.

关键词： MgO Diffusion Oxidation Atomic mobility CALPHAD Wagner's model

study on the dynamic behavior of herringbone gear structure of marine propulsion system powered by double-cylinder turbines

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science China(Technological sciences) 2022年第3期65卷 611-630页

作者： XU JiangHai JIAO ChunXiao ZOU DongLin ta na RAO Zhushi state Key Laboratory of Mechanical system and Vibration Institute of VibrationShock and NoiseShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center for Advanced ship and Deep-sea Exploration Shanghai 200240China

Propulsion systems powered by double-cylinder turbines(DCT)are widely used in large-scale ***,the nonlinear instability leads to hidden dangers associated with the safe operation,and there is a lack of theoretical and systematic research on this *** on the gear transmission principle and non-Newtonian thermal elastohydrodynamic lubrication(EHL)theory,a torsional model of a two-stage herringbone system forced by unsymmetrical load is *** nonlinear and time-varying factors of meshing friction,meshing stiffness,and gear pair backlash are included in the model,and multiple meshing states,including single-and double-sided impact are *** nonlinear phenomena of the dynamic system are explored and the effects of the unsymmetrical load on the system stability are *** results indicate that the stability of the gear system is improved,and that the back-sided impact gradually disappears with the increases of load ratio between the two inputs and the input load ***,it is found that the gear pairs on the low-load side experience more severe vibration than those on the high-load ***,the stability of the gear pairs decreases along the power transmission path of the multistage gear *** results of this research will be useful when making predictions of the stability of such systems and in the optimization of the load parameters.

关键词： DCT propulsion system DI-sO herringbone gears unsymmetrical load nonlinear instability mechanism

Co_3O_4 nanosheets:synthesis and catalytic application for CO oxidation at room temperature

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science China Chemistry 2014年第6期57卷 873-880页

作者： LV YongGe LI Yong ta na sHEN WenJie state Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of Sciences

Hexagonal β-Co(OH)2 nanosheets with edge length of 50 nm and thickness of 10 nm were hydrothermally synthesized with the aid of *** calcination at 350°C in air,the β-Co(OH)2 nanosheets was converted into Co3O4 nanosheets with a similar *** analyses during the calcination process identified that the β-Co(OH)2 precursor was initially dehydrated to HCoO2 and subsequently transferred into *** being applied to catalyze CO oxidation at room temperature,the Co3O4 nanosheets exhibited a higher activity than the conventional spherical *** was perhaps related to the partial exposure of the{112}planes over the Co3O4 *** porous structure generated during the calcination process also provided significant amounts of surface defects,which might contribute to the enhanced catalytic activity as well.

关键词： Co3O4 nanosheets CO oxidation morphology-dependence nanocatalysis

Location and Trajectory Identification from Microblogs

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Journal of Computer science & Technology 2019年第4期34卷 727-746页

作者： na ta Guo-Liang Li Jun Hu Jian-Hua Feng school of Journalism and Communication Renmin University of ChinaBeijing 100872China Department of Computer science and Technology Tsinghua UniversityBeijing 100084China Airbnb Network(Beijing)Inc. Beijing 100020China

The rapid development of social networks has resulted in a proliferation of user-generated content(UGC),which can benefit many *** this paper,we study the problem of identifying a user's locations from microblogs,to facilitate effective location-based advertisement and *** the location information in a microblog is incomplete,we cannot get an accurate location from a local *** such,we propose a global location identification method,*** combines multiple microblogs of a user and utilizes them to identify the user's *** not only improves the quality of identifying a user's location but also supplements the location of a microblog so as to obtain an accurate location of a *** facilitate location identification,Glitter organizes points of interest(POIs)into a tree structure where leaf nodes are POIs and non-leaf nodes are segments of POIs,e.g.,countries,cities,and *** the tree structure,Glitter first extracts candidate locations from each microblog of a user which correspond to some tree *** Glitter aggregates these candidate locations and identifies top-κlocations of the *** the identified top-κuser locations,Glitter refines the candidate locations and computes top-κlocations of each *** achieve high recall,we enable fuzzy matching between locations and *** propose an incremental algorithm to support dynamic updates of *** also study how to identify users'trajectories based on the extracted *** propose an effective algorithm to extract high-quality *** results on real-world datasets show that our method achieves high quality and good performance,and scales well.

关键词： location identification microblog trajectory identification

An effective round ball tool in electrochemistry process as novel reuse fabrication technology

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中国有色金属学会会刊：英文版 2012年第S3期22卷 825-830页

作者： P.s.pa Department of Digital Content Design Graduate School of Toy and Game DesignNational Taipei University of Education

A reuse fabrication module using micro electrochemistry (MECM) with a round-ball tool to remove the defective In2O3 snO2 thin film from the surfaces of digital paper display was *** etching effect improves that the number of the round-balls decreases for promoting the concentration of electric power and increasing discharge *** a small size of the round-ball tool takes less time for the same amount of In2O3 snO 2 layer removal since the effect of MECM is easily developed for supplying of sufficient electrochemical power.A higher feed rate of the poly ethylene terephthalate (PET) diaphragm combines with enough electric power to drive fast etching rate.A pulsed direct current can improve the effect of dreg discharge and is advantageous to couple this current with the fast feed rate of the *** the ultra-precise etching of In2O 3 snO2,the optoelectronic semiconductor industry can effectively reuse the defective products,reducing production *** precision etching process is of high efficiency and requires only a short period of time to remove the In2O3 snO2 nanostructures.

关键词： thin film round-ball tool In2O3snO2 micro electrochemistry digital paper display

Design of mesoporous ZnCosiOx hollow nanoreactors with specific spatial distribution of metal species for selective CO_(2)hydrogenation

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nano Research 2023年第4期16卷 5601-5609页

作者： Xinyao Wang Runping Ye Melis s.Duyar Cameron Alexander Hurd Price Hao Tian Yanping Chen na ta Hao Liu Jian Liu state Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of sciences Beijing 100049China Department of Chemical and Process Engineering University of SurreyGuildfordSurrey GU27XHUK Department of Chemical Engineering and Analytical science University of ManchesterManchesterUK Centre for Clean Energy Technology University of Technology SydneySydneyBroadway NSW 2007Australia DICP-surrey Joint Centre for Future Materials Advanced Technology InstituteUniversity of SurreyGuildfordSurrey GU27XHUK

In heterogeneous catalysis,the precise placement of active components to perform unique functions in cooperation with each other is a tremendous *** migration of matter on micro/nano-scale caused by diffusion is a promising pathway for design of catalytic nanoreactors with precise active sites location and controllable microenvironment through compartmentalization and confinement ***,we report two categories of mesoporous ZnCosiOx hollow nanoreactors with different metal distributions and microenvironment engineered by the diffusion behavior of metal species in confined ***-shelled hollow structures with well-distributed metal species were obtained by adopting core@shell structured ZnCo-zeolitic imidazolate framework(ZIF)@siO2 as a template and employing three stages of hydrothermal treatment including the decomposition of ZIF,diffusion of metal species into the silica shell,and Ostwald ***,the formation of yolk@shell structure with a collective(Zn-Co)metal oxide as the yolk was achieved by direct pyrolysis of ZnCo-ZIF@*** CO_(2)hydrogenation,ZnCosiOx with double-shelled hollow structures and yolk@shell structures respectively afford CO and CH_(4)as main product,which is related with different dispersion and location of active sites in the two *** study provides an efficient method for the synthesis of catalytic nanoreactors on the basis of insights of the atomic diffusion in confined space at the mesoscale.

关键词： mesoporous materials structure-activity relationships supported catalysts metal-organic frameworks nanostructures

Fabrication of monodispersed B,N co-doped hierarchical porous carbon nanocages through confined etching to boost electrocatalytic oxygen reduction

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nano Research 2023年第1期16卷 290-298页

作者： Xuefei Wang Chao Han Haitao Li panpan su na ta Yanfu Ma Zhenguo Huang Jian Liu school of Civil&Environmental Engineering University of Technology SydneySydneyNSW2007Australia state Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China DICP-surrey Joint Centre for Future Materials University of Surrey GuildfordSurreyGU27XHUK

Dual heteroatom-doped carbons have attracted widespread research attention as catalysts in the field of energy storage and conversion due to their unique electronic structures and chemical *** particular,boron and nitrogen co-doped carbon(B,N@C)has shown great potential for photo/electrocatalytic ***,more needs to be done for rational designing and regulating the structure of these materials to improve their catalytic ***,monodispersed hierarchical porous B,N@C nanocages were fabricated by pyrolyzing zeolite imidazole framework(ZIF)which was treated with ammonia borane or boric acid via an integrated double-solvent impregnation and nanocofined-etching *** treated ZIF-8 provided an essential structural template to achieve B,N co-doped hierarchical structures with micro/meso/macro multimodal pore size *** resultant B,N@C nanocages displayed high catalytic activities for electrochemical oxygen reduction reaction(ORR)in alkaline media,outperforming most carbon-based catalysts,particularly from the perspective of the half-wave *** high catalytic performance is due to the enhanced activity by the coexistence of B and N and the mass transfer promoted by the unique hierarchical porous structure.

关键词： heteroatom doping hierarchical porous carbon host-guest chemistry confined etching electrocatalysis mass transfer