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A medical robot for needle placement therapy in liver cancer

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第4期11卷 263-269页

作者： Xing-guang DUAN gui-bin bian Hong-hua ZHAO Xing-tao WANG Qiang HUANG Intelligent Robotics Institute Beijing Institute of Technology Beijing 100081 China

Hepatocellular carcinoma (HCC) is the second most common malignancy in *** microwave ablation (MWA) is an effective method for liver cancer,a robotic surgical system with ultrasound-directed was designed to assist surgeons on positioning the *** robotic system includes a surgical robot with 5 degrees of freedom,a workstation for path-planning and image processing,a conventional 2D ultrasound device,and an electromagnetic (EM) tracking *** space,clinical operation requirements and optimal mechanical structure are the key factors to be considered in designing a medical robot suitable for use by *** on the mechanics of the needle placement robot,we have conducted detailed kinematic analysis,including a combined numerical algorithm and coordinate ***,the feasibility of the needle placement robot has been validated by experiment.

关键词： Surgical robot Needle insertion Inverse kinematics Numerical solution

Development and Evaluation of a 7-DOF Haptic Interface

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IEEE/CAA Journal of Automatica Sinica 2018年第1期5卷 261-269页

作者： Jian-Long Hao Xiao-Liang Xie gui-bin bian Zeng-Guang Hou Xiao-Hu Zhou Key Laboratory of Management and Control for Complex Systems Institute of Automation University of Chinese Academy of Sciences Beijing 100190 China IEEE

With the development of human robot interaction technologies, haptic interfaces are widely used for 3 D applications to provide the sense of touch. These interfaces have been utilized in medical simulation, virtual assembly and remote manipulation tasks. However, haptic interface design and control are still critical problems to reproduce the highly sensitive touch sense of humans. This paper presents the development and evaluation of a7-DOF(degree of freedom) haptic interface based on the modified delta mechanism. Firstly, both kinematics and dynamics of the modified mechanism are analyzed and presented. A novel gravity compensation algorithm based on the physical model is proposed and validated in simulation. A haptic controller is proposed based on the forward kinematics and the gravity compensation algorithm. To evaluate the control performance of the haptic interface, a prototype has been implemented. Three kinds of experiments: gravity compensation, static response and force tracking are performed respectively. The experimental results show that the mean error of the gravity compensation is less than 0.7 N and the maximum continuous force along the axis can be up to 6 N. This demonstrates the good performance of the proposed haptic interface.

关键词： Dynamic modeling evaluation haptic interface impedance control

Synthesis of Planar-Chiral[2.2]Paracyclophane-Based Oxazole-Pyrimidine Ligands and Application in Nickel-Catalyzed 1,2-Reduction ofα,β-Unsaturated Ketones

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Chinese Journal of Chemistry 2024年第7期42卷 705-710页

作者： Juan Wang Qing-Xian Xie Xiang Li Chang-bin Yu Yong-gui Zhou School of Chemistry Dalian University of Technology2 Linggong RoadDalianLiaoning 116024China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianLiaoning 116023China

The planar-chiral ligands have been widely applied as a class of unique and significant ligands in asymmetric *** them,chiral[2.2]paracycyclophane has emerged as a privileged type of planar-chiral framework and has been utilized as an important toolbox due to their structural ***,we design and synthesize[2.2]paracyclophane-derived oxazole-pyrimidine ligands(abberviated as PYMCOX).These N,N-ligands with stable properties,rigid structure and large steric hindrance performed successfully in nickel-catalyzed asymmetric 1,2-reduction ofα,β-unsaturated ketones,affording the chiral allylic alcohols with up to 99%yield and 99%***,this reduction reaction could be conducted on gram-scale without loss of activity and enantioselectivity,and the chiral ligand could be conveniently recovered with high yield.

关键词： Oxazole-pyrimidine ligands Planar chirality Nickel Hydroboration Asymmetric synthesis

Heterogeneous integration of 2D materials on Si charge-coupled devices as optical memory

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Science China(Information Sciences) 2024年第6期67卷 190-197页

作者： Zheng bian Feng TIAN Zongwen LI Xiangwei SU Tianjiao ZHANG Jialei MIAO bin YU Yang XU Yuda ZHAO College of Integrated Circuits Hangzhou Global Scientific and Technological Innovation CentreZhejiang University

Optical memory integrates the function of optical sensing in memory devices, remarkably promoting the interconnection between sensory and memory terminals. Silicon charge-coupled photodetectors and floating gate memory have been widely used in imaging and storage technologies, respectively. However,the heterogeneous integration of the two devices requires technological innovation and complex electrical connections. In this work, we adopt a three-dimensional layer stacking method to design a novel optical memory device. On the top of Si charge-coupled photodetectors, we successively deposit two-dimensional graphene,hexagonal boron nitride, and molybdenum disulfide as a floating gate layer, a tunneling layer, and a readout layer, respectively. By applying a gate bias on lightly doped Si, a deep depletion layer is formed with a high voltage potential drop. Under dark conditions, the depletion layer cannot be filled, and the electric field across the h-BN tunnel barrier is relatively small. Under light irradiation, the deep depletion layer is gradually filled, and the h-BN tunneling layer withstands the increasing electric field, resulting in charge storage in the floating gate layer. Based on this mechanism, the device exhibits a gate voltage-dependent operation mode, including an integrated optical sensing-memory mode and an electrically driven storage mode. Under moderate gate voltage, the device can effectively detect the optical information with varied intensity and store the optical information in the floating gate, displaying optically controlled memory characteristics. Our work demonstrates a compact device structure for optical memory and displays excellent optically controlled memory performance, which can be applied in artificial vision systems.

关键词： heterogeneous integration charge-coupled device floating gate optical memory molybdenum disulfide lightly doped silicon

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Optimal extent of lymphadenectomy improves prognosis and guides adjuvant chemotherapy in esophageal cancer: A propensity scorematched analysis

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1537-1547页

作者： Ji-Ming Tang Shu-Jie Huang Qi-bin Chen Han-Sheng Wu gui-bin Qiao Department of Thoracic Surgery Guangdong Provincial People’s HospitalGuangzhou 510080Guangdong ProvinceChina Department of Thoracic Surgery The First Affiliated Hospital of Shantou University Medical CollegeShantou 515041Guangdong ProvinceChina

BACKGROUND The optimal extent of lymphadenectomy in esophageal squamous cell carcinoma(ESCC)patients remained *** To explore the ideal number of cleared lymph nodes in ESCC patients undergoing upfront *** In this retrospective,propensity score-matched study,we included 1042 ESCC patients who underwent esophagectomy from November 2008 and October *** who underwent neoadjuvant therapy were *** collected pa-tients’clinicopathological features and information regarding lymph nodes,in-cluding the total number of resected lymph nodes(NRLN),and pathologically diagnosed positive lymph nodes(RPLN).SPSS and R software were used for statistical *** Among the included 1042 patients,two cohorts:≤21(n=664)and>21 NRLN(n=378)were *** final prognostic model included four variables:T stage,N,venous thrombus,and the number of removed lymph *** them,NRLN>21 was determined as an independent prognosticator after surgery for esophageal cancer(hazards regression=0.66,95%confidence interval:0.50-0.87,P=0.004).A nomogram was created based on the regression coefficients of the variables in the final *** the training cohort,the predictive model dis-played an uncorrected five-year overall survival C-index of 0.659,with a bootstrap-corrected C-index of *** the subgroup analysis,adjuvant chemotherapy was beneficial in the subgroup with NRLN>21 and RPLN≤0.16 and NRLN≤21 and RPLN>*** NRLN>21 was an independent prognostic factor after ESCC *** combination of NRLN and RPLN may provide a reference for adjuvant chemotherapy use in potential beneficiaries.

关键词： Esophageal squamous cell carcinoma Lymphadenectomy Adjuvant chemotherapy Prognosis Nomogram

Application of CFD and FEA Coupling to Predict Structural Dynamic Responses of A Trimaran in Uni-and Bi-Directional Waves

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China Ocean Engineering 2024年第1期38卷 81-92页

作者： LIAO Xi-yu XIA Jin-song CHEN Zhan-yang TANG Qin ZHAO Nan ZHAO Wei-dong gui Hong-bin Marine Design&Research Institute of China Shanghai 200011China Ship Structure Division China Ship Scientific Research CenterWuxi 214082China College of Ocean Engineering Harbin Institute of TechnologyWeihaiWeihai 264209China State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentDalian University of TechnologyDalian 116024China School of Foreign Studies Jiangnan UniversityWuxi 214122China

To predict the wave loads of a flexible trimaran in different wave fields,a one-way interaction numerical simulation method is proposed by integrating the fluid solver(Star-CCM+)and structural solver(Abaqus).Differing from the existing coupled CFD-FEA method for monohull ships in head waves,the presented method equates the mass and stiffness of the whole ship to the hull shell so that any transverse and longitudinal section stress of the hull in oblique waves can be ***,verification study and sensitivity analysis are carried out by comparing the trimaran motions using different mesh sizes and time step *** on the wave elevation of uni-and bi-directional waves is also carried *** a comprehensive analysis on the structural responses of the trimaran in different uni-directional regular wave and bi-directional cross sea conditions is carried out,***,the differences in structural response characteristics of trimaran in different wave fields are *** results show that the present method can reduce the computational burden of the two-way fluid-structure interaction simulations.

关键词： CFD-FEA fluid-structure coupling structural responses trimaran bi-directional cross sea

The formation and evolutionary characteristics of organic matter and pyrites in the continental shales of the 3^(rd)submember of Chang 7 Member,Yanchang formation,Ordos Basin,China

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Energy Geoscience 2024年第2期5卷 31-39页

作者： Ruikang bian State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development Beijing 102206China Key Laboratory of Shale Oil and Gas Exploration&Production Technology SinopecBeijing 102206China SINOPEC Exploration&Production Research Institute Beijing102206China

Through microscopic analyses(e.g.,organic macerals,thin section observation,scanning electron microscope(SEM)imaging of fresh bedding planes via argon ion milling,and energy spectrum tests)combined with Rock-Eval analyses,this study systematically investigated the organic matter and pyrites in the continental shales in the 3^(rd)submember of the Chang 7 Member(Chang 7^(3)submember)in the Yanchang Formation,Ordos Basin and determined their types and the formation and evolutionary *** results are as *** organic matter of the continental shales in the Chang 7^(3)submember is dominated by amorphous bituminites and migrabitumens,which have come into being since the early diagenetic stage and middle diagenetic stage A,*** formation and transformation of organic matter is a prerequisite for the formation of *** Ordos Basin was a continental freshwater lacustrine basin and lacked sulphates in waters during the deposition of the Chang 7 ***,the syndiagenetic stage did not witness the formation of large quantities of *** the basin entered early diagenetic stage A,large quantities of sulfur ions were released as the primary organic matter got converted into bituminites and,accordingly,pyrites started to ***,this stage featured poorer fluid and spatial conditions compared with the syndepositional stage due to withdraw of water,the partial formation of bituminites,and a certain degree of *** a result,large quantities of pyrrhotite failed to transition into typical spherical framboidal pyrites but grew into euhedral monocrystal *** addition,pyrites are still visible in the migrabitumens in both microfractures and inorganic pores of mudstones and shales,indicating that the pyrite formation period can extend until the middle diagenetic stage A.

关键词： Organic matter Pyrite Formation and evolution Continental shale Chang 7^(3)submember Ordos Basin

Root-derived long-distance signals trigger ABA synthesis and enhance drought resistance in Arabidopsis

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Journal of Genetics and Genomics 2024年第7期51卷 749-761页

作者： Qian-Qian Liu Jin-Qiu Xia Jie Wu Yi Han gui-Quan Zhang Ping-Xia Zhao Cheng-bin Xiang Division of Life Sciences and Medicine Division of Molecular&Cell BiophysicsHefei National Science Center for Interdisciplinary Sciences at the MicroscaleUniversity of Science and Technology of ChinaThe Innovation Academy of Seed DesignChinese Academy of SciencesHefeiAnhui 230027China College of Life Sciences Anhui Agricultural UniversityHefeiAnhui 230036China College of Agronomy South China Agricultural UniversityGuangzhouGuangdong 510642China School of Biology and Basic Medical Sciences Soochow UniversitySuzhouJiangsu 215123China

Vascular plants have evolved intricate long-distance signaling mechanisms to cope with environmental stress,with reactive oxygen species(ROS)emerging as pivotal systemic signals in plant stress ***,the exact role of ROS as root-to-shoot signals in the drought response has not been *** this study,we reveal that compared with wild-type plants,ferric reductase defective 3(frd3)mutants exhibit enhanced drought resistance concomitant with elevated NINE-CIS-EPOXYCAROTENOID DIOXYGENASE 3(NCED3)transcript levels and abscisic acid(ABA)contents in leaves as well as increased hydrogen peroxide(H_(2)O_(2))levels in roots and *** experiments distinctly illustrate that drought resistance can be conferred by the frd3 rootstock regardless of the scion genotype,indicating that long-distance signals originating from frd3 roots promote an increase in ABA levels in ***,the drought resistance conferred by the frd3 mutant rootstock is weakened by the CAT2-overexpressing scion,suggesting that H_(2)O_(2)may be involved in long-distance ***,the results of comparative transcriptome and proteome analyses support the drought resistance phenotype of the frd3 *** together,our findings substantiate the notion that frd3 root-derived long-distance signals trigger ABA synthesis in leaves and enhance drought resistance,providing new evidence for root-to-shoot long-distance signaling in the drought response of plants.

关键词： frd3 Drought resistance Root-to-shoot long-distance signals Reactive oxygen species(ROS) H_(2)O_(2) Iron ABA

Long-wave instabilities

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Science China Mathematics 2024年第8期67卷 1761-1776页

作者： Dongfen bian Emmanuel Grenier School of Mathematics and Statistics Beijing Institute of TechnologyBeijing 100081China Unité de Mathématiques Pures et Appliquées CNRS UMR 5669Ecole Normale Supérieure de LyonLyon 69007France

This paper aims to give a detailed presentation of long-wave instabilities of shear layers for NavierStokes equations,and in particular to give a simple and easy-to-read presentation of the study of the OrrSommerfeld equation and to detail the analysis of its *** these analyses,we prove the existence of long-wave instabilities in the cases of slowly rotating fuids,slightly compressible fuids,or fuids with Navier boundary conditions,under smallness conditions.

关键词： Navier-Stokes equations boundary layers Prandtl equations

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