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Bio-Adaption between magnesium Alloy Stent and the Blood Vessel:A Review

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Journal of materials Science & Technology 2016年第9期32卷 815-826页

作者： jun ma Department of Chemical Biological and BioengineeringNorth Carolina Agricultural and Technical State UniversityGreensboroNCUSA NSF Engineering Research Center-Revolutionizing Metallic Biomaterials North Carolina Agricultural and Technical State UniversityGreensboroNC USA

Biodegradable magnesium （Mg） alloy stents are the most promising next generation of bio-absorbable stents. In this article, we summarized the progresses on the in vitro studies, animal testing and clinical trials of biodegradable Mg alloy stents in the past decades. These exciting findings led us to propose the importance of the concept ＂bio-adaption＂ between the Mg alloy stent and the local tissue microenvironment after implantation. The healing responses of stented blood vessel can be generally described in three overlapping phases： inflammation, granulation and remodeling. The ideal bio-adaption of the Mg alloy stent, once implanted into the blood vessel, needs to be a reasonable function of the time and the space/dimension. First, a very slow degeneration of mechanical support is expected in the initial four months in order to provide sufficient mechanical support to the injured vessels. Although it is still arguable whether full mechanical support in stented lesions is mandatory during the first four months after implantation, it would certainly be a safety design parameter and a benchmark for regulatory evaluations based on the fact that there is insufficient human in vivo data available, especially the vessel wall mechanical properties during the healing/remodeling phase. Second, once the Mg alloy stent being degraded, the void space will be filled by the regenerated blood vessel tissues. The degradation of the Mg alloy stent should be 100% completed with no residues, and the degradation products （e.g., ions and hydrogen） will be helpful for the tissue reconstruction of the blood vessel. Toward this target, some future research perspectives are also discussed.

关键词： Mg stent Bio-adaptation Vessel Wound healing

A review for dynamics of collective behaviors of network of neurons

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Science China(Technological Sciences) 2015年第12期58卷 2038-2045页

作者： ma jun TANG jun Department of Physics Lanzhou University of Technology College of Science China University of Mining and Technology

The nervous system is composed of a large number of neurons, and the electrical activities of neurons can present multiple modes during the signal transmission between neurons by changing intrinsic bifurcation parameters or under appropriate external forcing. In this review, the dynamics for neuron, neuronal network is introduced, for example, the mode transition in electrical activity, functional role of autapse connection, bifurcation verification in biological experiments, interaction between neuron and astrocyte, noise effect, coherence resonance, pattern formation and selection in network of neurons. Finally, some open problems in this field such as electromagnetic radiation on electrical activities of neuron, energy consumption in neurons are presented.

关键词： Neuronal network defects spiral wave target wave electromagnetic induction

BDS/GPS deformation analysis of a long-span cable-stayed bridge based on colored noise filtering

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Geodesy and Geodynamics 2023年第2期14卷 163-171页

作者： jun ma China Railway Siyuan Survey and Design Group Co. LTDWuhan 430079China School of Surveying and mapping Wuhan UniversityWuhan 430079China

Combining GPS and BDS technology to monitor the deformation of long-span railway bridges with stricter deformation control requirements is of significance to the safety and control of the bridge and the safety of railway *** studies have ignored the influence of coloured noise in the deformation time *** is not conducive to accurate deformation analysis of long-span railway ***,GPS,BDS and GPS/BDS monitoring data of Ganjiang Bridge located in Ganzhou city,Jiangxi Province,China are adopted in this paper to filter the coloured noise in the deformation time series by principal component analysis(PCA),and the influence of coloured noise on the deformation analysis results of railway bridge is *** experimental results show that the diurnal temperature difference causes the mid-span and the tower of the railway cable-stayed bridge to deform with a period of about one day in the vertical and longitudinal directions,*** colored noise will make the uncertainty of the deformation parameter estimation overly *** can significantly reduce the coloured noise,and thus reduce the uncertainty of deformation parameter estimation by about 73%.Moreover,the average difference between the daily periodic motion amplitudes of the monitoring points obtained by using GPS and BDS deformation time series is 1.65 *** use of GPS/BDS deformation time series is not only helpful to reduce the influence of coloured noise,but also can reduce the difference between amplitude analysis results obtained from GPS and BDS deformation time series.

关键词： Long-span railway bridges GNSS deformation monitoring Coloured noise PCA

Structure and Inclination Angle of the Spiral Galaxy M31

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Chinese Physics Letters 2001年第10期18卷 1420-1422页

作者： ma jun National Astronomical Observatories Chinese Academy of SciencesBeijing 100012 Joint Laboratory of Optical Astronomy Chinese Academy of SciencesBeijing 100012

The mathematical form, the symmetry of the spiral structure, and the projection of the galactic disc on the image of the spiral galaxy M31 have been directly studied. It is found that M31 has two symmetric arms, i.e. the pitch angles of the two arms are nearly equal;these are 7.7° and 8.0°, respectively. Using the method proposed in this letter, the inclination angle of the galactic disc ofM31 is also obtained, which is 77.5° and is in good agreement with previously published results.

关键词： M31 galactic galaxy

Transcriptional activators and activation mechanisms

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Protein & Cell 2011年第11期2卷 879-888页

作者： jun ma Division of Biomedical Informatics Division of Developmental BiologyCincinnati Children's Research FoundationUniversity of Cincinnati College of MedicineCincinnatiOH 45229USA

Transcriptional activators are required to turn on the expression of genes in a eukaryotic *** bound to the enhancer can facilitate either the recruitment of RNA polymerase II to the promoter or its *** article examin... 详细信息

关键词： activator transcription co-activator enhancer promoter signal transduction development

Preparation of Pt/γ-Al2O3-C Heterogeneous Catalyst for Highly Selective Hydrogenation of Cinnamaldehyde Towards Cinnamyl Alcohol

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Chemical Research in Chinese Universities 2017年第4期33卷 660-665页

作者： ma jun Sichuan Province Institutions of Higher Education and Key Laboratory of Land Resources Evaluation and Monitoring in Southwest Ministry of Education Chengdu 610068 P. R. China

A Pt/γ-Al2O3-C heterogeneous catalyst with improved catalytic performance was successfully prepared. Bayberry talmin（BT）, an abundant natural plant polyphenol, was utilized to modifiy the surface of the Pt/γ-Al2O3 matrix and then stabilize Pt nanoparticles（NPs）. The catalyst was systematically and specifically characterized by a collec- tion of analytic tools including XRD, XPS, FTIR, TEM, and TG. It was found that the Pt NPs were envenly dispered on the γ-Al2O3-C matrix. Meanwhile, when the catalyst was applied for selective hydrogenation of cilmamalde- hyde（Cma） in the presence of KOH promoter in solvent, excellent catalytic performance was obtained. The selecti- vity to cinnamyl alcohol（CMO） reached 97.88% with 88.45% Cma conversion within 30 min in the presence of 0.037 mol/L KOH, without significant loss of catalytic activity even under cyclic measurements for 5 times. The excelleut catalytic performances should be ascribed predominantly to the uniform and stable dispersion ofPt NPs on the γ-Al2O3-C matrix and the excellent heat stability of BT.

关键词： Heterogeneous catalyst Pt/γ-Al2O3-C Barberry tannin Selective hydrogenation Ciunamaldehyde

The Changing of Common Priors in Sequential Auctions

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Journal of Systems Science & Complexity 2016年第5期29卷 1342-1357页

作者： QIAO Heng ma jun School of Economics Central University of Finance and Economics Business School University of International Business and Economics

In sequential auctions the phenomenon of declining prices is often observed, which in theory can be represented by a supermartingale. This paper employs the perspective that bidders' values may change over stages and the common priors are sequentially adjusted by the remaining bidders. It is shown that the declining price sequence can be explained by the adjustment of common priors between auctions. The adjustment of common priors is characterized by stochastic orders. Sufficient and necessary conditions for a supermartingale price sequence are derived.

关键词： First-price sealed-bid auction private-value paradigm sequential auctions.

Hybrid scheme for three-cell multi-user MIMO cellular networks

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The Journal of China Universities of Posts and Telecommunications 2014年第5期21卷 37-42页

作者： ma Yan-jun School of Communication Engineering Xi'an University of Science and Technology

Orthogonal schemes are usually adopted for cell-edge users in a cellular network, where the spectrum is poorly utilized. A new interference alignment （IA） based space-division hybrid （IA-SDH） scheme is proposed by joint design transmit precoding matrices and beamforming matrices for a three-cell constant cellular network, where users at cell-center work with a conventional scheme while users at cell-edge utilize an IA scheme. Therefore, the cell-edge users suffer no interference and cell-center users are only affected by negligible inter-cell interference. Analysis simulation shows that more users can be served simultaneously than that of a conventional scheme in certain user distributions.

关键词： iterference alignment degree of freedom interference channel

Control of firing activities in thermosensitive neuron by activating excitatory autapse

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Chinese Physics B 2021年第10期30卷 171-179页

作者： Ying Xu jun ma School of mathematics and Statistics Shandong Normal UniversityJi’nan 250014China Department of Physics Lanzhou University of TechnologyLanzhou 730050China School of Science Chongqing University of Posts and TelecommunicationsChongqing 430065China

Temperature has distinct influence on the activation of ion channels and the excitability of neurons,and careful change in temperature can induce possible mode transition in the neural *** formation and development of autapse connection to neuron can enhance its self-adaption to external stimulus,and thus the firing patterns in neuron can be controlled *** autapse is activated to drive a thermosensitive neuron,which is developed from the FitzHugh-Nagumo neural circuit by incorporating a thermistor,and the dynamics in the neural activities is explored to find mode dependence on the temperature and autaptic *** is found that the firing modes can be controlled by temperature,and the neuron is wakened from resting state to periodic oscillation with the increase of ***,the intensity and the intrinsic time delay in the autapse are respectively adjusted to control the neural activities,and it is confirmed that appropriate setting for autaptic current can balance and enhance the temperature effect on the neural activities.

关键词： thermosensitive neuron autapse firing pattern bifurcation