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疝修复补片:材料设计与应用的最新进展

中国组织工程研究 2025年第16期29卷 3494-3502页

作者：陈静宇洪阁郭宁刘天军天津中医药大学天津市301617 中国医学科学院北京协和医学院生物医学工程研究所天津市生物医学材料重点实验室天津市300192 河北大学基础医学院河北省保定市071000

背景:与传统的缝合方式相比,采用补片修复腹壁缺陷的无张力疝修补手术能有效减少术后疼痛和疝气复发率,已经成为近年来治疗腹疝的首选方法。目的:归纳总结不同疝修复补片在应用过程中的优缺点。方法:以“腹壁缺损,疝气补片,疝气治疗”... 详细信息

背景:与传统的缝合方式相比,采用补片修复腹壁缺陷的无张力疝修补手术能有效减少术后疼痛和疝气复发率,已经成为近年来治疗腹疝的首选方法。目的:归纳总结不同疝修复补片在应用过程中的优缺点。方法:以“腹壁缺损,疝气补片,疝气治疗”为中文检索词,以“abdominal wall defect,hernia patches,hernia treatment”为英文检索词,分别检索中国知网、谷歌学术和PubMed数据库,检索时限主要为2018年1月至2024年2月,同时采用少数经典的早期文献以概述疝修复补片的发展历程,通过阅读题目和摘要进行初步筛选,排除与疝修复材料相关性较低的文献,最终纳入90篇文献进行归纳总结。结果与结论:根据制备材料的不同可以将疝修复补片分为不可吸收人工合成补片、可吸收人工合成补片、天然高分子补片和复合补片。不可吸收补片具有较高的机械强度,有益于疝气区域的组织愈合,但体内长期存在的补片可能会引发身体的免疫反应,导致炎症和疼痛。可吸收人工合成补片与天然高分子补片具有良好的组织相容性、降解性,但机械强度不稳定。复合材料补片继承了传统不可吸收补片优良的机械性能,同时通过可吸收部分的设计降低了一些并发症发生的风险。在疝修复补片的后续研究中,科研人员应重点关注如何将新技术与复合补片结合起来,形成多功能的疝修复补片。

关键词：腹壁缺损疝修复补片聚丙烯抗菌补片疝气不可吸收补片可吸收补片复合补片

Seismic Imaging of Complex Structures in the Tarim Basin

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Journal of Earth Science 2015年第4期26卷 586-591页

作者： ning guo Chao Wu Stuart Fagin Geo Tech Groups LLC Institute of Exploration and Development CPNCKorla Geo Image Resources LLC

Conventional time imaging techniques are not capable of producing accurate seismic imaging of the subsurface in the mountain front of the Tarim Basin, China. Their imaged structures have led to some major drilling failures before, bearing a disrepute that ＂their structural closures have wheels and their structural highs have springs＂. This article first lists the imaging challenges, and explains in a schematic why the time imaging techniques fail in this area. Then through a series of real data examples, it demonstrates that when there exist lateral velocity variations, depth imaging is the only solution to tackle the imaging challenges in this area. Depth imaging accounts for the complexity of the wavefield, therefore produces superior and geological plausible images. The core task in properly performing depth imaging is building the velocity model. This article stresses some the main aspects in this regard.

关键词： time migration depth migration seismic image quality velocity model building anisotropy.

Functional Neuroimaging in the New Era of Big Data

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Genomics, Proteomics & Bioinformatics 2019年第4期17卷 393-401页

作者： Xiang Li ning guo Quanzheng Li Massachusetts General Hospital and Harvard Medical School

The field of functional neuroimaging has substantially advanced as a big data science in the past decade,thanks to international collaborative projects and community *** we conducted a literature review on functional neuroimaging,with focus on three general challenges in big data tasks:data collection and sharing,data infrastructure construction,and data analysis *** review covers a wide range of literature types including perspectives,database descriptions,methodology developments,and technical *** show how each of the challenges was proposed and addressed,and how these solutions formed the three core foundations for the functional neuroimaging as a big data science and helped to build the current data-rich and data-driven ***,based on our review of recent literature on the upcoming challenges and opportunities toward future scientific discoveries,we envisioned that the functional neuroimaging community needs to advance from the current foundations to better data integration infrastructure,methodology development toward improved learning capability,and multi-discipline translational research framework for this new era of big data.

关键词： Big data Neuroimaging Machine learning Health informatics fMRI

Boundary condition modelling and identification for cantilever-like structures using natural frequencies

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Chinese Journal of Aeronautics 2019年第6期32卷 1451-1464页

作者： Wei LIU Zhichun YANG Le WANG ning guo School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Xi’an Aerospace Propulsion Institute Xi’an 710100China

The actual boundary conditions of cantilever-like structures might be non-ideally clamped in engineering practice, and they can also vary with time due to damage or aging. Precise modelling of boundary conditions, in which both the boundary stiffness and the boundary mass should be modelled correctly, might be one of the most significant aspects in dynamic analysis and testing for such structures. However, only the boundary stiffness was considered in the most existing methods. In this paper, a boundary condition modelling and identification method for cantilever-like structures is proposed to precisely model both the boundary stiffness and the boundary mass using sensitivity analysis of natural frequencies. The boundary conditions of a cantilever-like structure can be parameterized by constant mass, constant rotational inertia,constant translational stiffness, and constant rotational stiffness. The relationship between natural frequencies and boundary parameters is deduced according to the vibration equation for the lateral vibration of a non-uniform beam. Then, an iterative identification formulation is established using the sensitivity analysis of natural frequencies with respect to the boundary parameters. The regularization technique is also used to solve the potential ill-posed problem in the identification *** simulations and experiments are performed to validate the feasibility and accuracy of the proposed method. Results show that the proposed method can be utilized to precisely model the boundary parameters of a cantilever-like structure.

关键词： Boundary condition identification Boundary condition modelling Iterative method Natural frequency Sensitivity analysis

Wave Optics in Discrete Excitable Media

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Chinese Physics Letters 2012年第5期29卷 107-110页

作者： GU guo-Feng WEI Hai-Ming TANG guo-ning College of Physics Science and Technology Guangxi Normal UniversityGuilin 541004

Refraction and reflection of planar waves in a discrete excitable medium is numerically investigated by using the Greenberg-Hasting *** is fonnd that the medium is anisotropic because the speed of the planar wave depends on the excitability of the medium and the direction of wave *** reflection,diffraction,refraction,double refraction and delayed refraction are observed by using the correct choice of model *** the incident angle is larger than the critical angle,the reflection,which is a back refraction,takes *** reflection angle changes with the incident *** refraction in certain situations obeys Shell's ***,our results demonstrate that the incident,refracted and reflected waves can have different *** reflected and refracted waves can disappear.

关键词： parameters. refraction incident

Integrated Entry Guidance for Reusable Launch Vehicle

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Chinese Journal of Aeronautics 2007年第1期20卷 1-8页

作者： ning guo-dong ZHANG Shu-guang FANG Zhen-ping School of Aeronautical Science and Technology Beijing University of Aeronautics and Astronautics Beijing 100083 China

A method for the implementation of integrated three-degree-of-freedom constrained entry guidance for reusable launch vehicle is presented. Given any feasible entry conditions, terminal area energy management interface conditions, and the reference trajectory generated onboard then, the method can generate a longitudinal guidance profile rapidly, featuring linear quadratic regular method and a proportional-integral-derivative tracking law with time-varying gains, which satisfies all the entry corridor constraints and meets the requirements with high precision. Afterwards, by utilizing special features of crossrange parameter, establishing bank-reversal corridor, and determining bank-reversals according to dynamically adjusted method, the algorithm enables the lateral entry guidance system to fly a wide range of missions and provides reliable and good performance in the presence of significant aerodynamic modeling uncertainty. Fast trajectory guidance profiles and simulations with a reusable launch vehicle model for various missions and aerodynamic uncertainties are presented to demonstrate the capacity and reliability of this method.

关键词： guidance trajectory generation entry onboard constraint robustness

Influence of Torsion Deformation on Textures of Cold Drawing Pearlitic Steel Wires

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Acta Metallurgica Sinica(English Letters) 2015年第6期28卷 707-714页

作者： ning guo Bo Song Bing-Shu Wang Qing Liu Faculty of Materials and Energy Southwest University Department of Materials Science and Engineering Chongqing University Department of Materials Science and Engineering Fuzhou University

The influence of torsion deformation on textures of cold drawing pearlific steel wires was investigated by twisting the wires to different number of revolutions. Macro-texture （over the entire wire cross section） associated with torsion deformation was investigated by X-ray diffraction, while micro-texture （near the wire surface） was characterized by EBSD. The results show that the （110） macro-texture increases at the beginning of torsion and then decreases with increasing of torsion strain, while the （110） micro-texture decreases linearly with increasing of torsion strain. The relationships between the （110） fiber texture and the microhardness of the wires are also discussed.

关键词： Pearlite Cold drawing Torsion Texture

Effect of free-end torsion on microstructure and mechanical properties of AZ31 bars with square section

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Journal of Materials Science & Technology 2021年第10期69卷 20-31页

作者： Bo Song Zhiwen Du ning guo Qingshan Yang Fang Wang Shengfeng guo Renlong Xin School of Materials and Energy Southwest UniversityChongqingChina School of Metallurgy and Materials Engineering Chongqing University of Science and TechnologyChongqing401331China College of Materials Science and Engineering Chongqing UniversityChongqingChina

In this study,a rolled AZ31 bar with square section was *** reciprocating torsion was performed to maintain the shape of the *** microstructure evolution of AZ31 bar during torsion and its influence on compressive anisotropy were investigated in *** showed that reciprocating torsion can simultaneously enhance yield strength in three compressive directions,and reduce compressive *** torsion generated profuse dislocations and{10–12}twin boundaries to harden the micro-hardness and yield *** torsion can also generate new texture component which is mainly from the orientation of newly generated{10–12}*** new twin-structures will be responsible for the reduction in compressive ***,uneven deformation features in twisted sample were systematically investigated.

关键词： AZ31 Square bar Torsion Twin Texture Anisotropy

Effects of traverse speed on weld formation,microstructure and mechanical properties of ZK60 Mg alloy joint by bobbin tool friction stir welding

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Chinese Journal of Aeronautics 2021年第12期34卷 238-250页

作者： Gaohui LI Li ZHOU Haifeng ZHANG Sanfeng LUO ning guo State Key Laboratory of Advanced Welding ami Joining Harbin Institute of TechnologyHarbin 150001China Shandong Provincial Key Laboratory of Special Welding Technology Harbin Institute of Technology(Weihai)Weihai 264209China

ZK60B(Mg-6%Zn-0.6%Zr)alloy joints fabricated by bobbin tool friction stir welding(BTFSW)with various traverse speeds were *** sound joint fabricated by the BTFSW was possible under the appropriate welding *** severe plastic deformation during BTFSW resulted in dispersion and segregation of the Zr-rich particles within the stirred zone(SZ)followed by evolution of a bimodal grain structure with distributed bands of 0.8-1.7μm ultrafine grains and 4.1-7.1μm equiaxed ***-hardness of SZ is substantially reduced in contrast to that of parent metal(PM)in spite of the finer grain size owing to dissolution of Mg-Zn based precipitates having hardening effects on alpha-Mg *** the decrease in traverse speed,randomization degree of the plasticized metal flow increases,which is evidenced by the randomized arc line pattern at the low traverse *** all defect-free joints,the 200 mm/min joint exhibits the weakest isotropy of texture within SZ and the best tensile properties,which has reduced ultimate tensile strength and yield strength by 5.4% and by 22.2%,respectively,as compared to the *** randomized texture hinders the joint fracturing within SZ at low ***,a relatively high elongation of 10.8% was achieved,which corresponded to 72% of the PM value.

关键词： Bobbin tool Friction stir welding(FSW) Magnesium alloys Mechanical properties Microstructure evolution Traverse speed