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Effects of Electro-acupuncture Preconditioning on Focal Cere bral Blood Flow in Artery and Vein of Rats with Middle Cere bral Artery Occlusion

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中国康复医学杂志 2013年第12期28卷 1085-1092页

作者： JIA Jie GUO qingchuan GUO Zhenzhen YANG Xiaojiao Department of Rehabilitation Huashan Hospital Fudan University State Key Laboratory of Medical Neurobiology Fudan University

Objective:To investigate the effects of electro-acupuncture preconditioning on focal cerebral blood flow(CBF)in artery and vein of rats with middle cerebral artery occlusion(MCAO),and to provide experimental evidences for primary prevention of ischemic ***:Eighteen male Sprague-Dawley rats(two months old)were divided into 3 groups:electro-acupuncture preconditioning group(EA group),ischemia group(Is group)and Dazhui and Baihui sham group(six rats per group).The rats in the EA group were given electro-acupuncture preconditioning at Dazhui and Baihui with 2.15 density wave current for 30 minutes per day,5 days *** preconditioning,enhanced laser speckle contrast analysis was implemented to get false color images before making middle cerebral ischemia occlusion *** getting false color images two hours during ischemia by laser speckle contrast analysis ***:④Relative CBF in focal cortical artery:There were significant differences at every time point in EA group and Is group(P2. min after ischemia in sham group(P4. min after occlusion in EA group(P<0.05);compared with that before occlusion,there was significant difference from 105 min after occlusion in sham group(P<0.05);there was significant difference

关键词：康复医学临床精神疾病患者

A molecular dynamics and computational study of human KAT3 involved in KYN pathway

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Science China Chemistry 2013年第4期56卷 514-523页

作者： XU Yu ZHENG qingchuan YU LiYing ZHANG HongXing SUN ChiaChung State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University

Kynurenine aminotransferases （KATs） catalyze the transamination of kynurenine （KYN） pathway and endogenous KYNs have been suggested to highly correlate to abnormal brain diseases. HKAT3 is a key member of KAT family, while the binding mechanism of KYN and cofactor with HKAT3 has not been determined yet. In this study, we focus on the structure-function relationship among KYN, cofactor and HKAT3. The binding models of KYN complex and KYN＆cofactor complex were ob- tained and were studied by molecular dynamics （MD） simulations. We identified several critical residues and influence of conformational changes in human kynurenine aminotransferase 3 （HKAT3） complexes. The cofactor may contribute largely not only to the catalysis, but also to the binding. In addition, a hypothesis is proposed that a strong hydrophobic interaction between Tyr159 and Lys2.0 may influence the binding mode and the binding region of the substrate and the cofactor. Our re- suits will be a good starting point for further determination of the biological role.

关键词： kynurenine (KYN) kynurenine aminotransferases (KATs) ^-~ interaction molecular dynamic (MD) simulation interaction energy

Deep learning for complex displacement field measurement

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Science China(Technological Sciences) 2022年第12期65卷 3039-3056页

作者： LAN ShiHai SU Yong GAO ZeRen CHEN Ye TU Han ZHANG qingchuan CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefei 230027China Fuhuang Agile Device Inc.Hefei 230000China

Traction force microscopy(TFM)is one of the most successful and broadly-used force probing technologies to quantify the mechanical forces in living *** displacement recovery of the fluorescent beads within the gel substrate,which serve as the fiducial markers,is one of the key *** traditional methods of extracting beads displacements,such as PTV,PIV,and DIC,persistently suffer from mismatching and loss of high-frequency information while dealing with the complex deformation around the focal ***,this information is crucial for the further analysis since the cells mainly transmit the force to the extracellular surroundings through focal *** this paper,we introduced convolutional neural network(CNN)to solve the *** have generated the fluorescent images of the non-deformable fluorescent beads and the displacement fields with different spatial complexity to form the training *** the special image feature of the fluorescent images and the deformation with high complexity,we have designed a customized network architecture called U-DICNet for the feature extraction and displacement *** numerical simulation and real experiment show that U-DICNet outperforms the traditional methods(PTV,PIV,and DIC).Particularly,the proposed U-DICNet obtains a more reliable result for the analysis of the local complex deformation around the focal adhesions.

关键词： displacement recovery complex deformation measurement traction force microscopy convolutional neural network

Transverse vibration of pre-tensioned nonlocal nanobeams with precise internal axial loads

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Science China(Technological Sciences) 2011年第8期54卷 2007-2013页

作者： LI Cheng LIM C. W. YU JiLin ZENG qingchuan Department of Modern Mechanics University of Science and Technology of China Hefei 230026 China Department of Building and Construction City University ofHong Kong Tat Chee Avenue Kowloon Hong Kong SAR China China and USTC-CityU Joint Advanced Research Centre Suzhou 215123 China College of Water Conservancy and tlydropower Engineering Hohai University Nanjing 210098 China

This paper investigates the transverse vibration of a simply supported nanobeam with an initial axial tension based on the nonlocal stress field theory with a nonlocal size parameter. Considering an axial elongation due to transverse vibration, the internal axial tension is not precisely equal to the external initial tension. A sixth-order nonlinear partial differential equation that governs the transverse vibration for such nonlocal nanobeam is derived. Using a perturbation method, the relation between natural frequency and nonlocal nanoscale parameter is derived and the transverse vibration mode is solved. The external axial tension and nonlocal nanoscale parameter are proven to play significant roles in the nonlinear vibration behavior of nonlocal nanobeams. Such effects enhance the natural frequency and stiffness as compared to the predictions of the classical continuum mechanics models. Additionally, the frequency is higher if the precise internal axial load is considered with respect to that when only the approximate internal axial tension is assumed.

关键词： nonlocal stress natural frequency free vibration nonlocal nanoscale

Effects of microstructure on the torsional properties of biodegradable WE4. Mg alloy

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Journal of Materials Science & Technology 2020年第16期47卷 102-110页

作者： Yi Zhang Lili Tan qingchuan Wang Ming Gao Iniobong P.Etim Ke Yang Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

Torsional properties are important performance parameters for bone screw applications,but they are seldom studied,especially for newly developed biodegradable Mg *** this study,WE4. Mg alloy with different microstructures was achieved by equal channel angular pressing(ECAP)and heat treatment,and their torsional properties were *** addition,tensile properties were also tested as a *** results indicated that grain refinement led to higher torsional strength and ductility,while the second phases improved the torsional strength but reduced the *** texture was strengthened after ECAP,as a result the tensile strength increased,but the torsional strength did not increase and even decreased,especially for 2.pass ECAP sample with a typical basal fiber *** basal plane orientation deviation from the extrusion direction after 4.pass ECAP resulted in higher torsional strength and lower torsional ductility,but lower tensile strength and higher tensile ductility were *** implied that a strong fiber texture would reduce the torsional strength but improve the torsional ductility,which was different from its effect on tensile properties.

关键词： Torsional properties Texture ECAP WE4. Mg alloy

Mandatory IFRS adoption and executive compensation:Evidence from China

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China Journal of Accounting Research 2014年第1期7卷 9-29页

作者： qingchuan Hou Qinglu Jin Lanfang Wang Shanghai University of Finance and Economics

This study investigates how the mandatory adoption of International Financial Reporting Standards(IFRS) affects the contractual benefits of using accounting information to determine executive compensation in China. After controlling for firm and corporate governance characteristics, we find strong evidence supporting the positive role of mandatory IFRS adoption on the accounting-based performance sensitivity of executive compensation. Subsample analysis suggests that improvements in accounting-based performance sensitivity after IFRS adoption differ across regions with various levels of institutional quality and across firms that are affected to a different extent by the adoption. Additional analysis supports the argument that the positive effects of IFRS adoption on the use of accounting performance in executive compensation are driven by the reduction in accounting conservatism associated with IFRS adoption.

关键词： IFRS adoption Executive compensation Accounting-based performance sensitivity

How Mutations Affecting the Ligand-receptor Interactions： a Combined MD and QM/MM Calculation on CYP2.1 and Its Two Mutants

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Chemical Research in Chinese Universities 2015年第6期31卷 1029-1038页

作者： WANG Yan ZHENG qingchuan ZHANG Jilong XIE Mo ZHAN Jiuyu ZHANG Hongxing Institute of Theoretical Chemistry Jilin University Changchun 130021 P. R. China

Cytochrome P4.0（CYP） 2.l is a dual function monoxygenase with a crucial role in the metabolism of 6% of drugs on the market at present. The enzyme is of tremendous interest for its association with alcohol consumption, diabetes, obesity and fasting. Despite the abundant experimental mutagenesis data, the molecular origin and the structural motifs for the enzymatic activity deficiencies have not been rationalized at the atomic level. In this regard, we have investigated the effects of mutation on the structural and energetic characteristics upon single point mutations in CYP2.1, N2.9D and $366C. The molecular dynamics（MD） simulation combined with quantum mechanics/molecular mechanics（QM/MM） and noncovalent interaction（NCI） analysis was carried out on CYP2.I and its two mutants. The results highlight the critical role of Phe2.7, which is responsible for both structural flexibility and energetic variation, shortening the gap between the theory and the experimentally observed results of enzymatic activity decrease, The underlying molecular mechanism of the enzymatic activity deficiencies for mutants may be attributed to the changes of spatial position of Phe2.7 in the two mutants. This work provides particular explanations to how mutations affect ligand-receptor interactions based on combined MD and QM/MM calculations. Furthermore, the mutational effects on the activity of CYP2.1 obtained in the present study are beneficial to both the experimental and the computational works of CYPs and may allow researchers to achieve desirable changes in enzymatic activity.

关键词： Cytochrome P4.0(CYP) 2.l Molecular dynamics(MD) simulation Quantum mechanics/molecular mechanics(QM/MM, ONIOM) calculation Noncovalent interaction(NCI) analysis

Evaluation of the glacial isostatic adjustment(GIA) models for Antarctica based on GPS vertical velocities

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Science China Earth Sciences 2020年第4期63卷 575-590页

作者： Fei LI Chao MA Shengkai ZHANG Jintao LEI Weifeng HAO qingchuan ZHANG Wenhao LI Chinese Antarctic Center of Surveying and Mapping Wuhan UniversityWuhan 430079China

Due to the scarcity of data, modeling the glacial isostatic adjustment(GIA) for Antarctica is more difficult than it is for the ancient ice sheet area in North America and Northern Europe. Large uncertainties are observed in existing GIA models for Antarctica. Modern space-based geodetic measurements provide checks and constraints for GIA models. The present-day uplift velocities of global positioning system(GPS) stations at 73 stations in Antarctica and adjacent regions from 1996 to 2.14.have been estimated using GAMIT/GLOBK version 10.5 with a colored noise model. To easily analyze the effect of difference sources on the vertical velocities, and for easy comparison with both GIA model predictions and GPS results from Argus et al.(2.14. and Thomas et al.(2.11), seven sub-regions are divided. They are the northern Antarctic Peninsula, the Filchner-Ronne Ice Shelf, the Amundsen Sea coast, the Ross Ice Shelf, Mount Erebus, inland Southwest Antarctica and the East Antarctic coast,respectively. The results show that the fast uplift in the north Antarctic Peninsula and Pine Island Bay regions may be caused by the elastic response to snow and ice mass loss. The fast subsidence near Mount Erebus may be related to the activity of a magma body. The uplift or subsidence near the East Antarctic coast is very slow while the uplift for the rest regions is mainly caused by GIA. By analyzing the correlation and the associated weighted root mean square(WRMS) between the GIA predictions and the GPS velocities, we found that the ICE-6G_C(VM5a) model and the Geruo 13 model show the most consistency with our GPS results, while the W12. and IJ05_R2.series models show poor consistency with our GPS results. Although improved greatly in recent years, the GIA modeling in Antarctica still lags behind the modeling of the North American. Some GPS stations, for example the Bennett Nunatak station(BENN), have observed large discrepancies between GIA predictions and GPS *** of the

关键词： Antarctica GPS Glacial isostatic adjustment Vertical velocity Uncertainty

Theoretical Investigation on Binding Process of Allophanate to AUophanate Hydrolase

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Chemical Research in Chinese Universities 2015年第6期31卷 1023-1028页

作者： ZHANG Zidong ZHANG Jilong ZHENG qingchuan KONG Chuipeng LI Zhengqiang ZHANG Hongxing MA Jianzhang College of Wildlife Resource Northeast Forestry University Harbin 150040 P. R. China International Joint Research Laboratory of Nano-miero Architecture Chemistry Institute of Theoretical Chemistry Jilin University Changchun 130021 P. R. China Key Laboratory for Molecular Enzymology and Engineering Ministry of Education Jilin University Changchun 130012 P. R. China

t Several molecular simulation methods were integrated to investigate the detailed binding process of allo- phanate to allophanate hydrolase and predict their stable complex structure. The optimal enzyme-substrate complex conformation demonstrates that along with Arg307 and Tyr2.9, Gly12.0}is also one of the key anchor residues in the stable complex. The energetic calculation suggests the existence of an intermediate state in the enzyme-substrate binding process. The further atomic-level investigation illuminates that Tyr2.9, Arg307 and Ser172.can stabilize the substrate in the intermediate state. By this token, the residues Arg307 and Tyr2.9 function in both binding process and getting stable state.

关键词： Allophanate hydrolase Molecular dynamics simulation Substrate binding Free energy Intermediate state