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Nanomedicine Disrupts Stromal Barriers to Augment Drug Penetration for Improved Cancer Therapy

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Chinese Journal of Chemistry 2024年第10期42卷 1175-1189页

作者： guo-Feng Luo Wei-Hai Chen xian-Zheng Zhang state Key Laboratory of Oral&Maxillofacial Reconstruction and Regeneration Key Laboratory of Oral Biomedicine Ministry of EducationHubei KeyLaboratory of StomatologySchool&Hospital of StomatologyWuhan UniversityWuhanHubei 430079China Key Laboratoryof Biomedical Polymers of Ministry of Education&Departmentof Chemistry Wuhan UniversityWuhanHubei 430072China

Tumor stroma composing diverse extracellular matrixes(ECM)and stromal cells shapes a condensed physical barrier,which severely hampers the efficient accessibility of nanomedicine to tumor cells,especially these deep-seated in the core of *** barrier significantly compromises the antitumor effects of drug-loaded nanomedicine,revealing the remarkable importance of disrupting stromal barrier for improved tumor therapy with deep penetration *** achieve this goal,various nanoparticle-based strategies have been developed,including direct depleting ECM components via delivering anti-fibrotic agents or targeting stromal cells to suppress ECM expression,dynamic regulation of nanoparticles’physicochemical properties(i.e.,size,surface charge,and morphology),mechanical force-driven deep penetration,natural/biomimetic self-driven nanomedicine,and transcytosis-inducing *** these nanostrategies were systemically summarized in this review,and the design principles for obtaining admirable nanomedicine were *** the rapid development of nanotechnology,elaborate design of multifunctional nanomedicine provides new opportunities for overcoming the critical stromal barriers to maximize the therapeutic index of various therapies,such as chemotherapy,photodynamic therapy,and immunotherapy.

关键词： Nanomedicine Tumor stroma Deep penetration Enhanced drug perfusion Cancer therapy Drug carriers Biomaterials Nanotechnology

Solderability of Electrodeposited Fe-Ni Alloys with Eutectic SnAgCu Solder

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Journal of Materials Science & Technology 2007年第6期23卷 811-816页

作者： Jianjun guo Lei ZHANG Aiping xian J.K.Shang Sh-enyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Department of Materials Science and Engineering University of Illinois at Urbana-Champaign Urbana IL 61801 USA

Solderabilities of electrodeposited Fe-Ni alloys with SnAgCu solder were examined by wetting balance measurements and compared to those of pure Ni and pure Fe platings. Excellent solderability was found on the Ni-52Fe plating as both the wetting force and kinetics approached or exceeded those on the pure Ni. However, upon further increase in Fe content to 75 at. pct, the solderability of the alloy was severely degraded even though it was still better than that of the pure Fe plating. X-ray photoelectron spectroscopy showed that such a strong dependence of solderability on Fe content is related to the much thinner, incomplete oxide coverage of Ni-rich plating surface.

关键词： Solderability FeNi alloys Lead-free solders Wetting

Theoretical model of double-walled carbon nanotube pullout from a composite matrix

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Science China(Physics,Mechanics & Astronomy) 2012年第6期55卷 1004-1009页

作者： ZHOU LiJun kang YiLan guo JianGang Tianjin Key Laboratory of Modern Engineering Mechanics School of Mechanical EngineeringTianjin UniversityTianjin 300072China Department of Mechanical Engineering Tianjin University of Technology and EducationTianjin 300222China

A micromechanical model of double-walled carbon nanotube (DWCNT) pullout from a composite matrix is presented with the interfacial residual stress and van der Waals (vdW) forces taken into *** interfacial residual stress induced by thermal expansion coefficient (TEC) mismatch is introduced via thermo-elastic constitutive *** influence of vdW interactions between two layers of DWCNT on the interfacial stress distributions of DWCNT and matrix is *** analytical expressions of interfacial shear stress and the axial stresses of DWCNT and matrix are derived,***,the influences of temperature change,interfacial friction coefficient,DWCNT aspect ratio,DWCNT volume fraction and the relative modulus between DWCNT and matrix are illustrated and discussed.

关键词： double-walled carbon nanotubes pullout residual stress van der Waals forces

Cold signaling in plants:Insights into mechanisms and regulation

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Journal of Integrative Plant Biology 2018年第9期60卷 745-756页

作者： Xiaoyu guo Dongfeng Liu kang Chong Key Laboratory of Plant Molecular Physiology Institute of Botanythe Chinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China

To survive under cold temperatures plants must be able to perceive a cold signal and transduce it into downstream components that induce appropriate defense mechanisms. In addition to inducing adaptive defenses, such as the production of osmotic factors to prevent freezing and the reprogramming of transcriptional pathways, cold temperatures induce changes in plant growth and development which can affect the plant life cycle. In this review, we summarize recent progress in characterizing cold-related genes and the pathways that allow transduction of the cold signal in plants, focusing primarily on studies in Arabidopsis tbaliana and rice （Oryza sativa）. We summarize cold perception and signal transduction from the plasma membrane to the nucleus, which involves cold sensors, calcium signals, calciumbinding proteins, mitogen-activated protein kinase cascades, and the C-repeat binding factor/dehydrationresponsive element binding pathways, as well as trehalose metabolism. Finally, we describe the balance between plant organogenesis and cold tolerance mechanisms in rice. This review encapsulates the known cold signaling factors in plants and provides perspectives for ongoing cold signaling research.

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Spectral Analysis and Long-time Asymptotics for the Coherently-coupled Nonlinear Schrödinger System

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Acta Mathematica Sinica,English Series 2022年第11期38卷 2090-2114页

作者： Ming Ming CHEN xian guo GENG Ke Dong WANG School of Mathematics and Statistics Zhengzhou UniversityZhengzhou 450001P.R.China

On the basis of the spectral analysis of the 4×4 matrix Lax pair,the initial value problem of the coherently-coupled nonlinear Schrödinger system is transformed into a 4×4 matrix Riemann–Hilbert *** using the nonlinear steepest decent method,the long-time asymptotics of the solution of the initial value problem for the coherently-coupled nonlinear Schrödinger system is obtained through deforming the Riemann–Hilbert problem into a solvable model one.

关键词： Coherently-coupled nonlinear Schrödinger system nonlinear steepest descent method long-time asymptotics

CARRIER PHOTOGENERATION IN POLY(N-VINYL-CARBAZOLE)-BASED PHOTOCONDUCTIVE THIN-FILM DEVICES

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Chinese Journal of Polymer Science 2006年第6期24卷 553-558页

作者： Hui Jin Yan-bing Hou xian-guo Meng Feng Teng Key Laboratory of Luminescence and Optical Information Ministry of Education Institute of Optoelectronie Teehnology Beijing Jiaotong University Beijing 100044 China

In this paper, photoexcitation processes in the bilayer devices based on inorganic materials and poly（N-vinylcarbazole）（PVK） were investigated. In order to clarify the roles of inorganic materials in photoconductive properties of bilayer devices, TiO2 and ZnS were chosen to combine with PVK. A model for generation of photocurrent （Iph） in single layer device of PVK was obtained. It is deduced that the recombination rate constant （Pcomb） and the ionization rate constant （y） ofexcitons should be considered as the most important factors for Iph. For inorganic materials （TiO2 or ZnS）/PVK bilayer devices, in reverse bias of-4 V, the photocurrent of 115 mA/cm^2 in the TiO2/PVK device was observed, but the photocurrent in the ZnS/PVK device was only 10 mA/cma under the illumination light of 340 nm and the light intensity of 14.2 mW/cm^2. The weaker photocurrent is attributed to the absorption of ZnS within UV region and the energy offset at the interface between PVK and ZnS, which impedes the transport of charge carriers.

关键词： Polymer Inorganic semiconductor Photoconductive Photogeneration.

Gradient Descent Algorithm for Small UAV Parameter Estimation System

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Transactions of Nanjing University of Aeronautics and Astronautics 2017年第6期34卷 680-687页

作者： guo Jiandong Liu Qingwen Wang kang Key Laboratory of Unmanned Aerial Vehicle Technology of the Ministry of Industry and Information Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China

A gradient descent algorithm with adjustable parameter for attitude estimation is developed,aiming at the attitude measurement for small unmanned aerial vehicle(UAV)in real-time flight *** accelerometer and magnetometer are introduced to construct an error equation with the gyros,thus the drifting characteristics of gyroscope can be compensated by solving the error equation utilized by the gradient descent *** of the presented algorithm is evaluated using a self-proposed micro-electro-mechanical system(MEMS)based attitude heading reference system which is mounted on a tri-axis *** on-ground,turntable and flight experiments indicate that the estimation attitude has a good ***,the presented system is compared with an open-source flight control system which runs extended Kalman filter(EKF),and the results show that the attitude control system using the gradient descent method can estimate the attitudes for UAV effectively.

关键词： gradient descent algorithm attitude estimation quaternions small unmanned aerial vehicle(UAV)

Retention mechanism of calcium ferrite and compositions of ash on selenium during chemical looping gasification

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Particuology 2023年第8期79卷 143-152页

作者： Ziheng Han Huifen kang Nini Yuan Xintong guo Jingjing Ma Qingjie guo State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering College of Chemistry and Chemical EngineeringNingxia UniversityYinchuan750021China Key Laboratory of Clean Chemical Engineering in Universities of Shandong College of Chemical EngineeringQingdao University of Science&TechnologyQingdao266042China

Selenium pollution by coal utilization is of increasing ***-iron(Ca-Fe)oxygen carriers(OCs)and alkali metal ions have strong inhibitory effects on selenium,which can reduce the emissions of selenium *** retention mechanisms of selenium by Fe_(2)O_(3),CaFe_(2)O_(4),Ca_(2)Fe_(2)O_(5) and bottom ash are investigated during chemical looping gasification(CLG).Iron-based OC can oxidize H_(2)Se(g)to SeO_(2)(g);furthermore,lattice oxygen is released by Fe_(2)O_(3),contributing to the formation of an Fe-O-Se structure to retain selenium and form *** calcium ferrite is poorly oxidizing,it cannot oxidize H_(2)Se(g),but the CaO produced when OCs are reduced can react with H_(2)Se(g)to form CaSe(s),and this process can be promoted by H_(2)S(g).The best retention rates reached 32.301%when Ca_(2)Fe_(2)O_(5) was *** the cyclic experiment,the selenium retention of the bottom ash gradually *** metal ions in bottom ash are the main factor in retaining ***^(2+) and Mg^(2+) do not easily vaporize due to their high melting points;therefore,their selenium retention is significantly better than that of K^(+) and Na^(+).This research provided a new idea for the removal of selenium by using OCs and bottom ash par-ticles during CLG.

关键词： Selenium Chemical looping gasification Oxygen carrier Retention mechanism Ashcomposition

有限元分析技术在膝关节生物力学应用中的特点与优势

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中国组织工程研究 2025年第15期29卷 3253-3261页

作者：郭欢萱康志杰白小龙田晓燕金凤内蒙古医科大学附属医院影像诊断科内蒙古自治区呼和浩特市010010 内蒙古医科大学研究生院内蒙古自治区呼和浩特市010010

背景:有限元分析是一种先进的计算机工程技术,利用数学近似的方法对真实人体进行模拟,可以真实反映膝关节结构内部的生物力学特征,为理解膝关节疾病发病机制、优化手术方案以及开发新型植入材料提供了有效的工具。目的:对膝关节有限元... 详细信息

背景:有限元分析是一种先进的计算机工程技术,利用数学近似的方法对真实人体进行模拟,可以真实反映膝关节结构内部的生物力学特征,为理解膝关节疾病发病机制、优化手术方案以及开发新型植入材料提供了有效的工具。目的:对膝关节有限元模型的建立及其在膝关节疾病研究中的应用进行综述,并展望了未来的发展趋势。方法:第一作者于2024年4月以“Finite Element Analysis,FEA,knee joint,Finite Element Model,Knee Biomechanics,Knee Osteoarthritis,Knee Prosthesis,Knee Ligaments,Meniscus”为英文检索词在PubMed和EI数据库进行检索,以“有限元分析,有限元模型,膝关节,生物力学,骨关节炎,计算模型,膝关节假体,膝关节韧带,半月板”为中文检索词在中国知网和万方数据库进行检索,最终纳入75篇文献进行分析。结果与结论:①有限元分析法利用医学影像数据获得三维人体模型,将复杂的人体关节结构简化为有限且相互连接的单元,通过对模型施加外部载荷,直观地显示膝关节内部的应力分布。②研究者通过有限元分析深入研究膝关节在不同工况下的内部应力和应变分布,可发现膝关节内部载荷分配平衡改变时,关节软骨的过度载荷及部分区域的负荷下降,这种长期异常应力会引起软骨变形和磨损,最终缺失,对于理解生物力学因素如何引起膝关节退行性变至关重要。③有研究通过有限元分析评估膝骨关节炎患者采用太极拳、步态调整等物理治疗方法的效果,结果显示这些治疗方法减少了软骨的过度负荷,为临床治疗提供了科学理论依据。④临床医生通过有限元分析在手术前进行三维重建、数据测量和模拟手术,能够优化手术治疗策略;此外,还可以通过模拟不同假体的力学特征,改进假体的形状、材料和固定方式,减少患者的并发症,提高患者的治疗效果。⑤人工智能与有限元分析相结合使得有限元模型的构建更为精确和易于操作,极大提高了临床医生医疗实践的效率和患者的治疗效果。⑥有限元分析仅是数字化的模拟,与真实物理状态仍存在一定差异。

关键词：膝关节关节软骨半月板生物力学有限元分析有限元模型膝骨关节炎关节置换人工智能综述