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Decorin Induces Cardiac Hypertrophy by Regulating the CaMKⅡ/MEF-2 Signaling Pathway In Vivo

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Current Medical Science 2021年第5期41卷 857-862页

作者： yan yanG Wei-wei YU Wen yan Qin XIA Department of Geriatrics Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Objective:Cardiac hypertrophy is an adaptive reaction of the heart against cardiac overloading,but continuous cardiac hypertrophy can lead to cardiac remodeling and heart *** hypertrophy is mostly considered reversible,and recent studies have indicated that decorin not only prevents cardiac fibrosis associated with hypertension,but also achieves therapeutic effects by blocking fibrosis-related signaling ***,the mechanism of action of decorin remains unknown and ***:We determined the degree of myocardial hypertrophy by measuring the ratios of the heart weight/body weight and left ventricular weight/body weight,histological analysis and *** blotting was performed to detect the expression levels of CaMKⅡ,p-CaMKⅡ and MEF-2 in the ***:Our results confirmed that decorin can regulate the CaMKⅡ/MEF-2 signaling pathway,with inhibition thereof being similar to that of decorin in reducing cardiac ***:Taken together,the results of the present study showed that decorin induced cardiac hypertrophy by regulating the CaMKⅡ/MEF-2 signaling pathway in vivo,revealing a new therapeutic approach for the prevention of cardiac hypertrophy.

关键词： decorin cardiac hypertrophy calcium/calmodulin-dependent protein kinaseⅡ myocyte enhancer factor 2 atrial natriuretic peptide

Selective Laser Melting of Ti Composites: Latest Developments

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材料导报 2019年第5期33卷 729-730页

作者： DONG yangping LI Yulong yan Ming Shenzhen Key Laboratory for Additive Manufacturing of High-performance Materials Department of Materials Science and Engineering Southern University of Science and Technology Mechanical & Electrical Engineering School Nanchang University

Ti and Ti alloys are wonderful metal materials,showing excellent corrosion resistance,high specific strength and outstanding biocompatibility[1-2].They have been widely used in a variety of industries,including aerospace engineering,biomedical enginee-ring,off-shore drilling,automobile industry and even jewelry industry[1-2].To further improve their performance for satisfying the ever increasing challenging demands,Ti-based metal matrix composite becomes a cutting-edge research direction[3-4].However,intrinsic properties of most Ti materials,such as low thermal conductivity,high chemical reactivity and hexagonal close packed crystal structure,make their machining rather difficult and also push up the cost of using Ti *** reinforcement phases of Ti are often hard-and-refractory ceramic particles,it is even harder to fabricate Ti composite using conventional fabrication methods[1-4].

关键词： Titanium matrix composite The laser Aerospace engineering

SRP54 Negatively Regulates IFN-Beta Production and Antiviral Response by Targeting RIG-I and MDA5

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Virologica Sinica 2021年第2期36卷 231-240页

作者： Dong-Peng Wang Hong-yan Zhang Bo-Wei Liao Zhen Tong Zhi-Sheng Xu yan-Yi Wang yan yang Key Laboratory of Special Pathogens and Biosafety Wuhan Institute of VirologyCenter for Biosafety Mega-ScienceChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China

During virus infection,RIG-I-like receptors(RLRs)recognize viral RNAs and recruit the adaptor protein VISA to activate downstream signaling,leading to activation of transcription factors NF-κB and IRF3,which collaborate to induce type I interferons(IFNs).IFNs further induce expression of hundreds of IFN-stimulated genes(ISGs)that suppress viral replication and facilitate the adaptive immune *** production of IFNs is implicated in various immune *** we identified Signal Recognition Particle 54(SRP54)as a negative regulator of RLRs-induced antiviral *** of SRP54 inhibited RNA virus-triggered induction of IFN-b and increased viral replication,whereas knockdown of SRP54 had opposite ***,SRP54 interacted with both RIG-I and MDA5 and impaired their association with *** findings demonstrate that SRP54 acts as a negative regulator of RLRs-mediated innate immune response by disrupting the recruitment of VISA to RIG-I/MDA5.

关键词： TypeⅠinterferons(IFNs) SRP54 RLRs-induced signaling RIG-I/MDA5 and VISA interactions

Nonlinear dynamics of axially moving viscoelastic Timoshenko beam under parametric and external excitations

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Applied Mathematics and Mechanics(English Edition) 2015年第8期36卷 971-984页

作者： Qiaoyun yan Hu DING Liqun CHEN Shanghai Institute of Applied Mathematics and Mechanics Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai University Department of Mechanics Shanghai University

This investigation focuses on the nonlinear dynamic behaviors in the trans- verse vibration of an axiMly accelerating viscoelastic Timoshenko beam with the external harmonic excitation. The parametric excitation is caused by the harmonic fluctuations of the axial moving speed. An integro-partial-differential equation governing the transverse vibration of the Timoshenko beam is established. Many factors are considered, such as viscoelasticity, the finite axial support rigidity, and the longitudinally varying tension due to the axial acceleration. With the Galerkin truncation method, a set of nonlinear ordinary differential equations are derived by discretizing the governing equation. Based on the numerical solutions, the bifurcation diagrams are presented to study the effect of the external transverse excitation. Moreover, the frequencies of the two excitations are assumed to be multiple. Further, five different tools, including the time history, the Poincaré map, and the sensitivity to initial conditions, are used to identify the motion form of the nonlinear vibration. Numerical results also show the characteristics of the quasiperiodic motion of the translating Timoshenko beam under an incommensurable re- lationship between the dual-frequency excitations.

关键词： axially accelerating Timoshenko beam viscoelasticity nonlinear dynamics,parametric excitation external excitation

Friction and Wear Behaviors of MoS_2/Zr Coated HSS in Sliding Wear and in Drilling Processes

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Chinese Journal of Mechanical Engineering 2012年第6期25卷 1218-1223页

作者： DENG Jianxin yan Pei WU Ze Department of Mechanical Engineering Shandong UniversityJinan 250061China

MoS2 metal composite coatings have been successful used in dry turning, but its suitability for dry drilling has not been yet established. Therefore, it is necessary to study the friction and wear behaviors of MoS2/Zr coated HSS in sliding wear and in drilling processes. In the present study, MoS2/Zr composite coatings are deposited on the surface of W6Mo5Cr4V2 high speed steel（HSS）. Microstructural and fundamental properties of these coatings are examined. Ball-on-disc sliding wear tests on the coated discs are carried out, and the drilling performance of the coated drills is tested. Test results show that the MoS2/Zr composite coatings exhibit decreases friction coefficient to that of the uncoated HSS in sliding wear tests. Energy dispersive X-ray（EDX） analysis on the wear surface indicates that there is a transfer layer formed on the counterpart ball during sliding wear processes, which contributes to the decreasing of the friction coefficient between the sliding couple. Drilling tests indicate that the MoS2/Zr coated drills show better cutting performance compared to the uncoated HSS drills, coating delamination and abrasive are found to be the main flank and rake wear mode of the coated drills. The proposed research founds the base of the application of MoS2 metal composite coatings on dry drilling.

关键词： cutting tools coating MoS2 wear mechanisms

Crystallization of self-propelled particles on a spherical substrate

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Applied Mathematics and Mechanics(English Edition) 2019年第10期40卷 1387-1398页

作者： yan FANG Chen WANG Hongyuan JIANG CAS Key Laboratory of Mechanical Behavior and Design of Materials Hefei National Laboratory for Physical Science at the Microscale Department of Modern Mechanics University of Science and Technology of China

In this paper, we investigate the self-propelled particles confined on a spherical substrate and explore the structural and dynamic properties of self-propelled particles by controlling the packing fraction and activity. We find that these self-propelled particles freeze into the crystal with the increase in the packing fraction. We observe the pattern evolution of inevitable topological defects due to the geometric constraints of the spherical substrate. During the process of freezing, there is a transition from twelve isolated grain boundaries to the uniform distribution of defects with the increase in the self-propelled velocity. Finally, we establish a phase diagram of the freezing process. These results may deepen our understanding of active particles in complex and crowded environments.

关键词： self-prop elled particle freezing process geometric constraint defect

Magnetic labeling of natural lipid encapsulations wit ron-based nanoparticles

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Nano Research 2018年第6期11卷 2970-2991页

作者： Dewen Ye yan Li Ning Gu State Key Laboratory of Bioelectronics Jiangsu Key Laboratory for Biomaterials and Devices School of Biological Sciences & Medical Engineering Southeast University Nanjing 210096 China Collaborative Innovation Center of Suzhou Nano Science and Technology Suzhou 215123 China

With superior biocompatibility and unique magnetic properties, iron-based nanoparticles （IBNP） are commonly encapsulated in cells and extracellular vesicles （EV） to allow for magnetic force controlled drug delivery and non-invasive tracking. Based on their natural source and similar morphologs; we classify both cells and EVs as being natural lipid encapsulations （NLEs）, distinguishing them from synthetic liposomes. Both their imaging contrast and drug effects are dominated by the amount of iron encapsulated in each NLE, demonstrating the importance of magnetic labeling efficiency. It is known that the membranes function as barriers to ensure that substances pass in and out in an orderly manner. The most important issue in increasing the cellular uptake of IBNPs is the interaction between the NLE membrane and IBNPs, which has been found to be affected by properties of the IBNPs as well as NLE heterogeneity. Two aspects are important for effective magnetic labelling： First, how to effectively drive membrane wrapping of the nanoparticles into the NLEs, and second, how to balance biosafety and nanoparticle uptake. In this review, we will provide a systematic overview of the magnetic labeling of NLEs with IBNPs. This article provides a summary of the applications of magnetically labeled NLEs and the labeling methods used for IBNPs. The review also analyzes the role of IBNPs physicochemical properties, especially their magnetic properties, and the of NLEs in the internalization pathway. At the same time, the future of magnetically labeled NLEs is also discussed. development

关键词： magnetic labeling iron-based nanopartide (IBNP) natural lipid encapsulation(NLE) IBNP-membrane interactions

Influence of La-Mn-Al Co-Doping on Dielectric Properties and Structure of BST Thick Film

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Journal of Electronic Science and Technology of China 2009年第3期7卷 281-285页

作者： Mao-yan Fan Sheng-lin Jiang Department of Electronic Science and Technology Huazhong University of Science and Technology Wuhan 430074 China Yuxi Normal University Yuxi 653100 China.

A new sol-gel process is applied to fabricate the BST （BaxSr1-xTiO3） sol and nano-powder of La-Mn-Al co-doping with Ba/Sr ratio 65/35, and the BST thick film is prepared in the Pt/Ti/SiO2/Si substrate. The powder and thick film are characterized by X-ray diffraction and transmission electron microscope. The influence of La-Mn-Al co-doping on the dielectric properties and micro-structure of BST thick film is analyzed. The results show that the La, Mn, and Al ions can take an obvious restraint on the growth of BaSrTiO3 grains. The polycrystalline particles come into being during the crystallization of thick film, which may improve the uniformity and compactness of thick film. The influence of unequal-valence and doping amount on the leakage current, dielectric loss, and dielectric property are mainly discussed. The dielectric constant and dielectric loss of thick film are 1200 and 0.03, respectively, in the case of 1mol% La doping, 2mol% Mn doping, and 1mol% Al doping.

关键词： BST thick film dielectric property,La-Mn-Al co-doping sol-gel process

TRAJECTORY GENERATION AND CONTROL FOR NON-CIRCULAR CNC TURNING

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Chinese Journal of Mechanical Engineering 2008年第5期21卷 23-28页

作者： JIANG Simin yan Han WANG Xiankui Douglas Machine Inc. Alexandria MN 56308 USA Department of Precision Instruments and Mechanology Tsinghua University Beijing 100084 China

A trajectory generation method which is based on NURBS interpolation is studied to improve the fitting accuracy and smoothness of non-circular cross section and obtain higher accuracy of the final non-circular profile control. After using the NURBS, the most optimized and smooth trajectory for the linear actuator can be obtained. For the purpose of machining the non-circular cross section by CNC turning, the fast response linear actuator has been used. The control algorithm which is compound control of proportional-integral-differential （PID） and iterative learning control has been developed for non-circular profile generation. By using the NURBS interpolation and the compound control of PID and iterative learning control, the final motion accuracy of linear actuator has been improved, therefore, the machining accuracy of the non-circular turning can be improved.

关键词： Trajectory generation Iterative learning control Non-circular turning