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The integration of peri-implant soft tissues around zirconia abutments:Challenges and strategies

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Bioactive Materials 2023年第9期27卷 348-361页

作者： Kai tang Meng-Lin Luo Wei zhou Li-Na Niu ji-Hua Chen Fu Wang National Clinical Research Center for Oral Diseases&State Key Laboratory of Military Stomatology&Shaanxi Key Laboratory of Stomatology Department of ProsthodonticsSchool of StomatologyThe Fourth Military Medical UniversityXi’anShaanxi710032China Institute of Stomatology&Oral Maxilla Facial Key Laboratory The First Medical CenterChinese PLA General Hospital&Department of StomatologyThe First Medical CenterChinese PLA General HospitalBeijingChina

Stable soft tissue integration around the implant abutment attenuates pathogen penetration,protects underlying bone tissue,prevents peri-implantitis and is essential in maintaining long-term implant *** desire for“metal free”and“aesthetic restoration”has favored zirconia over titanium abutments,especially for implant restorations in the anterior region and for patients with thin gingival *** tissue attachment to the zirconia abutment surface remains a challenge.A comprehensive review of advances in zirconia surface treatment(micro-design)and structural design(macro-design)affecting soft tissue attachment is presented and strategies and research directions are *** tissue models for abutment research are *** for development of zirconia abutment surfaces that promote soft tissue integration and evidence-based references to inform clinical choice of abutment structure and postoperative maintenance are presented.

关键词： Zirconia Implant abutment Surface modification Soft tissue adhesion

A Computer Graphics-Based Framework for 3D Pose Estimation of Pedestrians

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Automotive Innovation 2021年第3期4卷 338-349页

作者： jisi tang Qing zhou State Key Laboratory of Automotive Safety and Energy School of Vehicle and MobilityTsinghua UniversityBeijing 100084China

In pedestrian-to-vehicle collision accidents,adapting safety measures ahead of time based on actual pose of pedestrians is one of the core objectives for integrated *** can significantly enhance the performance of passive safety system when active safety maneuvers fail to avoid *** study proposes a deep learning model to estimate 3D pose of pedestrians from *** conventional pedestrian image datasets do not have available pose features to work with,a computer graphics-based(CG)framework is established to train the system with synthetic *** 3D meshes of standing males are first transformed into several walking poses,and then rendered as images from multiple view ***,a matrix of 50 anthropometries,10 gaits and 12 views is built,in total of 6000 images.A two-branch convolutional neural network(CNN)was trained on the synthetic *** model can simultaneously predict 16 joint landmarks and 14 joint angles of pedestrian for each image with high *** errors of the predictions are 0.54 pixels and−0.06°,*** specific pose can then be completely reconstructed from the ***,the current study has established a CG-based pipeline to generate photorealistic images with desired features for the training;it demonstrates the feasibility of leveraging CNN to estimate the pose of a walking pedestrian from synthesized *** proposed framework provides a starting point for vehicles to infer pedestrian poses and then adapt protection measures accordingly for imminent impact to minimize pedestrian injuries.

关键词： Pose estimation Pedestrian safety Computer graphics Convolutional neural network

ANALYSIS SOLUTION OF ONE-DIMENSIONAL MATHEMATICAL MODEL ABOUT HEAVY METAL TRANSPORT FOR RIVER WATER

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Journal of Hydrodynamics 1992年第4期4卷 88-96页

作者： zhou, Xiaode tang, Yongji Shaanxi Inst of Mechanical Engineering Xi'an China

Water quality model about heavy metal under general initial and boundary conditions was studied. The model includes adsorption of suspended sediment, adsorption of bed load, advective diffusion of flow water, which affect the concentration of heavy metal in river water. Laplace transforms method was adopted, its integral equation of the concentration of diluting heavy metal and solid heavy metal was given. The characteristic of the model under constant solution was discussed. Using this model the prediction of mercury (Hg) ions concentration distribution along a section of Yellow River in Lanzhou, China was performed. The computational value is approximately equal to the measured value.

关键词： Heavy metals Laplace transforms Mathematical models Sedimentation Water pollution

Artificial Generation of High Harmonics via Nonrelativistic Thomson Scattering in Metamaterial

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Research 2019年第1期2019卷 1155-1164页

作者： Yongzheng Wen ji zhou State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

High harmonic generation allows one to extend the frequency of laser to a much broader regime and to study the electron dynamics of ***,severely limited by the vague high-order process in natural material and the unfriendly state of the commonly applied gas and plasma media,the ambitious goal of custom-design high harmonics remains exceptionally ***,we demonstrate that high harmonics can be artifcially designed and tailored based on a metamaterial *** the localized reconstruction of magnetic feld in a metamaterial,the nonlinear Tomson scattering,a ubiquitous electromagnetic process which people used to believe that it only occurs with the relativistic velocity,can be stimulated in a nonrelativistic limit,which drives anharmonic oscillation of free electrons and generates high *** explicit physical model and the numerical simulations perfectly demonstrate the artifcial generation and tailoring of the high *** novel mechanism is entirely dominated by the artifcial structure instead of the natural nonlinear *** not only provides unprecedented design freedom to the high harmonic generation but breaks the rigorous prerequisite of the relativistic velocity of the nonlinear Tomson scattering process,which ofers fascinating possibilities to the development of new light source and ultrafast optics,and opens up exciting opportunities for the advanced understanding of electrodynamics in condensed matters.

关键词： relativistic harmonics harmonic

不同强度运动抑制糖尿病大鼠肾脏PI3K/AKT/mTOR信号通路改善自噬的比较

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中国组织工程研究 2025年第11期29卷 2310-2318页

作者：周鸿雁张译丹季威刘霞湖南文理学院体育学院湖南省常德市415000 湖南师范大学体育学院体适能与运动康复湖南省重点实验室湖南省长沙市410012

背景:2型糖尿病损害肾功能。研究表明运动干预可以保护肾脏;鸢尾素可以通过抑制磷脂酰肌醇3-激酶/蛋白激酶B/雷帕霉素靶蛋白信号通路恢复自噬,保护糖尿病肾病患者的肾功能。目的:探讨运动能否通过抑制肾脏磷脂酰肌醇3-激酶/蛋白激酶B/... 详细信息

背景:2型糖尿病损害肾功能。研究表明运动干预可以保护肾脏;鸢尾素可以通过抑制磷脂酰肌醇3-激酶/蛋白激酶B/雷帕霉素靶蛋白信号通路恢复自噬,保护糖尿病肾病患者的肾功能。目的:探讨运动能否通过抑制肾脏磷脂酰肌醇3-激酶/蛋白激酶B/雷帕霉素靶蛋白信号通路过度激活来恢复自噬,改善肾损伤,以及分析不同方式运动产生影响的差异。方法:将6周龄的SD大鼠随机分为空白对照组(正常大鼠)和糖尿病组,其中糖尿病组大鼠经过高脂高糖喂养加腹腔注射低剂量1%链脲佐菌素(30 mg/kg)建立2型糖尿病模型。造模成功后再将糖尿病组大鼠随机分成糖尿病模型组、中强度持续运动组和高强度间歇运动组。两个运动组大鼠分别进行8周不同强度运动干预。取材后采用葡萄糖氧化酶法检测大鼠空腹血糖,使用试剂盒检测糖化血红蛋白水平,Elisa法检测血清胰岛素浓度,计算胰岛素抵抗指数,RT-PCR检测肾组织磷脂酰肌醇3-激酶、蛋白激酶B、雷帕霉素靶蛋白、Beclin-1、podocin、nephrin的基因表达量,Western Blot检测肾组织雷帕霉素靶蛋白及自噬标记蛋白LC3-1、LC3-2、Beclin-1的蛋白表达量。结果与结论:①2型糖尿病大鼠空腹血糖和糖化血红蛋白水平极显著性升高,胰岛素抵抗水平显著上升,胰岛素水平显著下降;两种运动均能使2型糖尿病大鼠空腹血糖和糖化血红蛋白水平极显著下降,胰岛素抵抗水平显著下降,胰岛素水平显著上升;与中强度持续运动组相比,高强度间歇运动组胰岛素水平显著上升。②2型糖尿病大鼠podocin、nephrin基因表达量显著降低;两种不同形式运动均能显著提高其表达;与高强度间歇运动组相比,中等强度持续性运动组足细胞相关蛋白基因表达有进一步上升趋势,但无显著性差异。③2型糖尿病大鼠肾组织磷脂酰肌醇3-激酶、蛋白激酶B、mTORC1的mRNA及蛋白的表达量显著增加,自噬标志蛋白Beclin-1、LC3-2表达量以及LC3-2/LC3-1显著降低;两种不同形式运动均能使肾组织磷脂酰肌醇3-激酶、蛋白激酶B、mTORC1的mRNA及雷帕霉素靶蛋白蛋白的表达量显著降低,自噬标志蛋白Beclin-1、LC3-2以及LC3-2/LC3-1显著升高;与中等强度持续性运动组相比,高强度间歇运动的磷脂酰肌醇3-激酶、蛋白激酶B、mTORC1的mRNA及雷帕霉素靶蛋白的蛋白表达量有进一步下降的趋势,Beclin-1、LC3-2以及LC3-2/LC3-1有进一步升高的趋势,但仅Beclin-1有显著性差异。④结果说明2型糖尿病肾脏足细胞损伤,自噬受到抑制,与磷脂酰肌醇3-激酶/蛋白激酶B/mTORC1信号通路被异常激活密切相关。高强度间歇运动和中等强度持续性运动可以保护糖尿病肾脏,减少足细胞损伤,促进自噬恢复,这可能与运动抑制磷脂酰肌醇3-激酶/蛋白激酶B/雷帕霉素靶蛋白信号通路过度激活有关。与中等强度持续性运动相比,高强度间歇运动恢复自噬的效果呈更优趋势,但足细胞蛋白表达稍有下降。

关键词：糖尿病肾病足细胞自噬高强度间歇运动中等强度持续性运动 PI3K AKT mTOR

INFLUENCE OF MOLECULAR STRUCTURES OF SECONDARY AMINE TERMINATED POLY(ESTER-AMINE)S ON THE CURING PERFORMANCE WITH EPOXY RESIN

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Chinese Journal of Polymer Science 2007年第6期25卷 545-553页

作者： Li-ming tang ji Feng Yu Wang Advanced Materials Laboratory Department of Chemical Engineering Tsinghua University Beijing 100084 China

Five secondary amine terminated poly（ester-amine）s （defined as PEA） with controlled molecular structures were synthesized through reacting excessive piperazine with phthalicdiglycol diacrylate （PDDA） and 1,1,1-trimethylolpropane triacrylate （TMPTA） at a constant secondary amine/acrylate group ratio of 1.5/1 and at different PDDA/TMPTA molar ratios. Both IR and ^1H-NMR spectra indicated that all acrylate groups were consumed in the reaction, based on which the structural parameters were calculated from the ^1H-NMR spectra. With decreasing PDDA/TMPTA ratio, the content of secondary amine, degree of branching, molecular weight, Tg and Td increased accordingly. These polymers were further used as both crosslinkers and flexibilizers for a linear epoxy resin E51 to form cured films under ambient condition. The gel content, relative hardness and Tg of the resulting films increased as PEA molecules changed from linear to highly branching structures. Due to the flexibility of PEA molecules, all the films possessed excellent mechanical performance.

关键词： Poly(ester-amine) Molecular structure Epoxy resin Cured film.

AIEgens in cell-based multiplex fluorescence imaging

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Science China Chemistry 2019年第10期62卷 1312-1332页

作者： Yabin zhou jin Hua Ben Zhong tang Youhong tang Faculty of Biological Engineering Sichuan University of Science and EngineeringYibin 644000China Institute for NanoScale Science and Technology Medical Device Research InstituteCollege of Science and EngineeringFlinders UniversityTonsleySouth Australia 5042Australia Discipline of Medical Biochemistry College of Medicine and Public HealthFlinders UniversityBedford ParkSouth Australia 5042Australia Department of Chemistry Hong Kong Branch of Chinese National Engineering Research Centre for Tissue Restoration and ReconstructionDivision of Biomedical EngineeringThe Hong Kong University of Science and TechnologyHong KongChina

Fluorescence imaging is an important branch of *** is non-invasive and provides superior spatial and temporal resolution during the real-time monitoring of biological samples of *** the spatial resolution limit of optical microscopes is about 200 nm,due to the diffraction limit,with the application of super-resolution fluorescence microscopy technologies this limit has been pushed below 30 *** makes it feasible to visualize biological structures in subcellular levels and to monitor subcellular biological processes in real ***,due to the complexity of the biological structure and components within cells,simultaneous staining and monitoring multiple intracellular components with different coloured fluorophores is often needed during multiplex imaging,to better understand biological ***-induced emission luminogens(AIEgen)and AIEgen based nanoparticles(NPs)have presented many advantages in fluorescence imaging,with strong potential for biological science and *** this review,we focus on the advantages of AIEgen and AIEgen NP in cell-based fluorescence imaging,and the latest advances of AIEgens in cell-based multiplex imaging are summarized and *** future perspectives are proposed.

关键词： aggregation induced emission cell imaging multiplex

High-Order Accurate Runge-Kutta (Local) Discontinuous Galerkin Methods for One- and Two-Dimensional Fractional Diffusion Equations

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Numerical Mathematics(Theory,Methods and Applications) 2012年第3期5卷 333-358页

作者： Xia ji Huazhong tang LSEC Institute of Computational MathematicsChinese Academy of SciencesP.O.Box 2719Beijing 100190China HEDPS CAPT and LMAMSchool of Mathematical SciencesPeking UniversityBeijing 100871China

As the generalization of the integer order partial differential equations(PDE),the fractional order PDEs are drawing more and more attention for their applications in fluid flow,finance and other *** paper presents high-order accurate Runge-Kutta local discontinuous Galerkin(DG)methods for one-and two-dimensional fractional diffusion equations containing derivatives of fractional order in *** Caputo derivative is chosen as the representation of spatial derivative,because it may represent the fractional derivative by an integral *** numerical examples show that the convergence orders of the proposed local Pk–DG methods are O(hk+1)both in one and two dimensions,where Pk denotes the space of the real-valued polynomials with degree at most k.

关键词： Discontinuous Galerkin method Runge-Kutta time discretization fractional derivative Caputo derivative diffusion equation

Time-Domain Nonlinear Wave-Current Interaction with A Steep Wave Riser Considering Internal Flow Effect

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China Ocean Engineering 2021年第3期35卷 410-421页

作者： tang Lian-yang CHENG Yong ji Chun-yan School of naval architecture and ocean engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Nippon Kaiji Kyokai(China)Co. LtdShanghai 200336China

The nonlinear dynamic response induced by the wave-current interaction on a deepwater steep wave riser(SWR)is numerically investigated based on a three-dimensional(3 D)time-domain finite element method(FEM).The governing equation considering internal flow is established in the global coordinate *** whole SWR consists of three segments:the decline segment,buoyancy segment and hang-off segment,in which the buoyancy segment is wrapped by several buoyancy modules in the middle section,leading to the arch bend and sag bend.A Newmark-β iterative scheme is adopted for the accurate analysis to solve the governing equation and update the dynamic response at each time *** proposed method is verified through the published results for the dynamic response of steel catenary riser(SCR)and static configuration of steel lazy wave riser(SLWR).Simulations are executed to study the influence of wave height,current velocity/direction,internal flow density/velocity and top-end pressure on the tension,configuration and bending moment of the *** results indicate that the influence of the current on the configuration and mechanical behavior of the SWR is greater than that of the wave,especially in the middle *** increasing current velocity,the suspending height of the middle section drops,meanwhile,its bending moment decreases accordingly,but the tension increases *** a fixed external load,the increasing internal flow density induces the amplification of the tension at the hang-off segment and the mitigation at the decline segment,while the opposite trend occurs at the bending moment.

关键词： steep wave riser(SWR) nonlinear dynamic response wave-current interaction time-domain finite element method(FEM)