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Expression of farnesyltransferase in primary liver cancer

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Chinese Medical Journal 2012年第14期125卷 2427-2431页

作者： SUI Guo-de zhang guang-yong NIU Zhao-jian HU San-yuan Department of General Surgery Qilu Hospital of ShandongUniversity Jinan Shandong 250012 China

Background Primary liver cancer （PLC） is a common malignant tumor. Over the past decade, although farnesyltransferase （FTase） has emerged as a significant target for anticancer therapies and has become a hotspot of cancer research, its exact mechanism of action remains unknown. The aim of this study was to investigate the expression of FTase in PLC and its role in the development of PLC. Methods Expression of FTase was detected by real-time fluorescent quantitative-polymerase chain reaction （FQ-PCR） in cancer and surrounding normal tissues from 32 patients with PLC. Results Expression of FTase mRNA in PLC was significantly higher than that in normal hepatic tissues （P 〈0.001）. Overexpression of FTase was as high as 87.5%. The positive rate for FTase mRNA in the high tendency to metastatic recurrence group was obviously higher than that in the low tendency to metastatic recurrence group （P=0.02）. The positive rate for FTase mRNA in patients with metastatic recurrence during postoperative follow-up was also significantly higher than that in those without metastatic recurrence （P=-0.01）. Conclusions The level of FTase mRNA expression in cancer tissues is much higher than in normal tissues. FTase may play an important role in the genesis and development of PLC and may be one of the reliable markers for the metastatic activity gained by liver tumor cells. FTase could be used clinically in predicting metastatic recurrence of PLC

关键词： primary liver cancer, farnesyltransferase fluorescent quantitative-polymerase chain reaction

维普期刊数据库

Planar matrices and arrays of Feynman diagrams:poles for higher k

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Communications in Theoretical Physics 2024年第4期76卷 1-13页

作者： Alfredo Guevara yong zhang Perimeter Institute for Theoretical Physics WaterlooON N2L 2Y5Canada Department of Physics&Astronomy University of WaterlooWaterlooON N2L 3G1Canada Society of Fellows Harvard UniversityCambridgeMA 02138United States of America CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesNo.19A Yuquan RoadBejing 100049China

Planar arrays of tree diagrams were introduced as a generalization of Feynman diagrams that enable the computation of biadjoint amplitudes m_(n)(^(k))for k>*** this follow-up work,we investigate the poles of m_(n)(^(k))from the perspective of such *** general k,we characterize the underlying polytope as a Flag Complex and propose a computation of the amplitude-based solely on the knowledge of the poles,whose number is drastically less than the number of the full *** an example,we first provide all the poles for the cases(k,n)=(3,7),(3,8),(3,9),(3,10),(4,8)and(4,9)in terms of their planar arrays of degenerate Feynman *** then implement simple compatibility criteria together with an addition operation between arrays and recover the full collections/arrays for such *** the way,we implement hard and soft kinematical limits,which provide a map between the poles in kinematic space and their combinatoric *** use the operation to give a proof of a previously conjectured combinatorial duality for arrays in(k,n)and(n-k,n).We also outline the relation to boundary maps of the hypersimplex Δ_(k,n) and rays in the tropical Grassmannian Tr(k,n).

关键词： Feynman diagrams biadjoint amplitudes poles

维普期刊数据库

Optimizing mechanical properties of HIPS fabricated with low-cost desktop 3D printers:investigating the impact of process parameters

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Advances in Manufacturing 2024年第2期12卷 379-395页

作者： Jin-Ting Xu guang-Wei zhang Man-Man Chen School of Automotive Engineering Dalian University of TechnologyDalian116024People’s Republic of China

Recently,low-cost desktop three-dimensional(3D)printers,employing the fused deposition modeling(FDM)technique,have gained widespread ***,most users cannot test the strength of printed parts,and little information is available about the mechanical properties of printed high-impact polystyrene(HIPS)parts using desktop 3D *** this study,the user-adjustable parameters of desktop 3D printers,such as crisscross raster orientation,layer thickness,and infill density,were *** experimental plans were designed using the Box-Behnken method,and tensile,3-point bending,and compression tests were carried out to determine the mechanical responses of the printed *** prediction models of the process parameters were regressed to produce the optimal combination of process *** experimental results showcase that the crisscross raster orientation has significant effects on the flexural and compression strengths,but not on the tensile *** an increase in the layer thickness,the tensile,flexural,and compression strengths first decreased and then increased,reaching their minimum values at approximately 0.16 mm layer *** addition,they all increased with an increase of infill *** was demonstrated that when the raster orientation,layer thickness,and infill density were 13.08°/–76.92°,0.09 mm,and 80%,respectively,the comprehensive mechanical properties of the printed HIPS were *** results can help end-users of desktop 3D printers understand the effects of process parameters on the mechanical properties,and offer practical suggestions for setting proper printing parameters for fabricating HIPS parts.

关键词： Desktop three-dimensional(3D)printers Fused deposition modeling(FDM) High-impact polystyrene(HIPS) Process parameters

Bioinspired Scraper-File Type Frequency-Doubling Ultrasonic Exciter

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Journal of Bionic Engineering 2024年第4期21卷 1801-1816页

作者： Wenshuai Wu Mingshuo zhang Zeming Li guang Yao Xinggang Jiang Deyuan zhang School of Mechanical Engineering and Automation Beihang UniversityBeijing100191China Institute of Bionic and Micro-Nano Systems Beihang UniversityBeijing100191China guangdong Provincial Key Laboratory of Minimally Invasive Surgical Instruments and Manufacturing Technology Guangdong University of TechnologyGuangzhou510006China

In the natural world,leaf-cutting ants cause vibrations through their mutual scraping of file-scraper *** this study,we designed a Biomimetic Ultrasonic Exciter(BUE)that imitates leaf-cutting *** operating characteristics of the BUE were studied through experimental testing and finite element *** results showed that the BUE could generate stable ultrasonic vibrations,and that the excitation frequency only needed to be half the Output Frequency(OF).This frequency-doubling phenomenon was conducive to achieving BUE *** further explore the phenomenon of frequency-doubling vibration output,this study designed scrapers of five different sizes,conducted excitation and first-order natural frequency measurement tests,and the corresponding finite element *** was found that each scraper could operate in frequency-doubling mode,but the operating frequency and natural mode frequencies did not correspond with one *** further explicate experimental and simulation results,a two-degrees-of-freedom vibration model was *** was evident that the contact relationship between the dentate disc and scraper introduced strong nonlinear factors into the system,accounting for the frequency-doubling phenomenon and the difference between the BUE’s operating and mode *** BUE could be expected to facilitate the production of high-power micro-ultrasonic generators and has potential application value in the fields of mechanical processing,industrial production,and medical health.

关键词： Leaf-cutting ants Power ultrasound Nonlinear vibration Ultrasonic scalpel Micro vibrator

A novel weld-pool-length monitoring method based on pixel analysis in plasma arc additive manufacturing

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Advances in Manufacturing 2024年第2期12卷 335-348页

作者： Bao-Ri zhang yong-Hua Shi Bionic Robot Research Department Ji Hua LaboratoryFoshan528200GuangdongPeople’s Republic of China guangdong Provincial Engineering Research Center for Special Welding Technology and Equipment School of Mechanical and Automotive EngineeringSouth China University of TechnologyGuangzhou510640People’s Republic of China

The real-time monitoring of the weld pool during deposition is important for automatic control in plasma arc additive *** obtain a high deposition accuracy,it is essential to maintain a stable weld pool *** this study,a novel passive visual method is proposed to measure the weld pool *** the proposed method,the image quality was improved by designing a special visual system that employed an endoscope and a *** also includes pixel brightness-based and gradient-based algorithms that can adaptively detect feature points at the boundary when the weld pool geometry *** algorithm can also be applied to materials with different solidification *** was performed to measure the real weld pool length in world coordinates,and outlier rejection was performed to increase the accuracy of the ***,tests were carried out on the intersection component,and the results showed that the proposed method performed well in tracking the changing weld pool length and was applicable to the real-time monitoring of different types of materials.

关键词： Plasma arc additive manufacturing(PAAM) Weld pool geometry Gradient analysis Real-time detection

Spray characteristics of different regions downstream of a swirl cup

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Chinese Journal of Aeronautics 2024年第8期37卷 124-143页

作者： Donghui WANG yong HUANG Hongzhou zhang Collaborative Innovation Center of Advanced Aero-Engine School of Energy and Power EngineeringBeihang UniversityBeijing 102206China National Key Laboratory of Science and Technology School of Energy and Power EngineeringBeihang UniversityBeijing 102206China

The spray characteristics of different regions downstream of swirl cups play a critical role in cold start and re-ignition of gas *** spray measurements were performed at the fuel pressures of 0.5,0.8,1.0,1.5,and 2.0 MPa and the fuel temperatures of-23,-13,-3,7,17 and 27℃,*** droplet size,droplet velocity,droplet number,and instantaneous spatial spray image of sprays from an aviation kerosene Jet-A were measured using a two-component phase Doppler particle analyzer and a digital off-axis holography *** the fuel pressure and temperature increase,the Sauter Mean Diameter(SMD)and spray non-uniformity of the Spray Shear Layer(SSL)gradually *** the fuel pressure increases,the SMD and spray non-uniformity of the Central Toroidal Recirculation Zone(CTRZ)gradually decrease,and the slopes of these curves both *** the fuel pressure increases,the SMD and spray nonuniformity of the CTRZ rapidly decrease at the fuel temperature of23℃,while slightly decrease at the fuel temperature of 27℃.The droplets in the CTRZ come from 3 different sources:simplex nozzle,venturi,and outside the *** the fuel pressure increases,the proportion of droplets recirculated from outside the CTRZ *** study proposed the concept of the“pressure critical point”for the swirl *** the fuel temperature decreases,the proportion of droplets recirculated from outside the CTRZ increases below the critical pressure,while decreases above the critical *** addition,through the models of liquid film formation and breakup on the curved cylindrical wall,a semi-theoretical model was established to predict the SMD of SSL for swirl *** prediction uncertainty of this model is less than 6%for all 14 conditions in this paper.

关键词： Swirl cup Sauter Mean Diameter(SMD) Spray non-uniformity Atomizing regions Semi-theoretical prediction Spray nozzles

Design method of multivariable PI controller for turboprop engine based on equivalent transfer function

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Chinese Journal of Aeronautics 2024年第9期37卷 237-260页

作者： Shancheng LI yong WANG Haibo zhang Jiangsu Province Key Laboratory of Aerospace Power System College of Energy and Power EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China

Traditional centralized Proportional Integral(PI)controller design methods based on Equivalent Transfer Functions(ETFs)have poor decoupling effect in turboprop *** this paper,a centralized PI design method based on dynamic imaginary matrix and equivalent transfer function is ***,a method for solving equivalent transfer functions based on the dynamic imaginary matrix is proposed,which adopts dynamic imaginary matrix to describe the dynamic characteristics of the system,and obtains the equivalent transfer function based on the dynamic imaginary matrix ***,for the equivalent transfer function,a central-ized PI control gain is designed using the Taylor expansion ***,this paper further proves that the centralized PI design method proposed in this paper has integral ***-ering the impact of altitude and Mach number on turboprop engines,a linear feedforward control method based on the transfer function matrix is further proposed based on the centralized PI con-troller,and the stability of the entire comprehensive control method is ***,to ensure the safe and effective operation of the turboprop engine,a temperature and torque limiting protection controller is designed for the turboprop *** results show that the centralized PI con-troller design method and linear feedforward control method proposed can effectively improve the control quality of turboprop engine control systems.

关键词： Multivariable control sys-tems Equivalent transfer function Disturbance compensation control Control parameter design Turboprop engine control

A Rapid Crack Detection Technique Based on Attention for Intelligent M&O of Cross-Sea Bridge

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China Ocean Engineering 2024年第5期38卷 866-876页

作者： ZHOU yong-chuan LI guang-jun WEI Wei WANG Ya-meng JING Qiang Hong Kong-Zhuhai-Macao Bridge Authority National Observation and Research Station of Material Corrosion and Structural Safety of Hong Kong-Zhuhai-Macao Bridge in guangdong Wuhan Maritime Communication Research Institute

Rapid and accurate segmentation of structural cracks is essential for ensuring the quality and safety of engineering projects. In practice, however, this task faces the challenge of finding a balance between detection accuracy and efficiency. To alleviate this problem, a lightweight and efficient real-time crack segmentation framework was ***, in the network model system based on an encoding-decoding structure, the encoding network is equipped with packet convolution and attention mechanisms to capture features of different visual scales in layers,and in the decoding process, we also introduce a fusion module based on spatial attention to effectively aggregate these hierarchical features. Codecs are connected by pyramid pooling model(PPM) filtering. The results show that the crack segmentation accuracy and real-time operation capability larger than 76% and 15 fps, respectively, are validated by three publicly available datasets. These wide-ranging results highlight the potential of the model for the intelligent O&M for cross-sea bridge.

关键词： bridge defect detection crack detection lightweight design

Effect of Active–Passive Deformation on the Thrust by the Pectoral Fins of Bionic Manta Robot

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Journal of Bionic Engineering 2024年第2期21卷 718-728页

作者： Yang Lu Shaomin Meng Cheng Xing Yiwei Hao yonghui Cao guang Pan yong Cao School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an710072China Unmanned Vehicle Innovation Center Ningbo Institute of NPUNingbo315103China State Key Lab of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou310027China Zhejiang Key Laboratory of Advanced Manufacturing Technology School of Mechanical EngineeringZhejiang UniversityHangzhou310027China

Bionic manta underwater vehicles will play an essential role in future oceans and can perform tasks,such as long-duration reconnaissance and exploration,due to their efficient *** manta wings’deformation is evident during the swimming *** improve the propulsion performance of the unmanned submersible,the study of the deformation into the bionic pectoral fin is *** this research,we designed and fabricated a flexible bionic pectoral fin,which is based on the Fin Ray®effect with active and passive deformation(APD)*** APD fin was actively controlled by two servo motors and could be passively deformed to variable *** APD fin was moved at 0.5 Hz beat frequency,and the propulsive performance was experimentally verified of the bionic pectoral fins equipped with different extents of *** results showed that the pectoral fin with active–passive deformed capabilities could achieve similar natural biological deformation in the wingspan *** average thrust(T)under the optimal wingspan deformation is 61.5%higher than the traditional passive deformed pectoral *** obtained results shed light on the design and optimization of the bionic pectoral fins to improve the propulsive performance of unmanned underwater vehicles(UUV).

关键词： Manta ray Bionic pectoral fin Fin Ray®effect Active-passive deformation(APD)