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Present situation of minimally invasive surgical treatment for early gastric cancer

World Journal of Gastrointestinal Oncology 2024年第4期16卷 1154-1165页

作者： Chun-Yan Li yi-feng wang Li-Kang Luo Xiao-Jun Yang The First Clinical Medical School Lanzhou UniversityLanzhou 730000Gansu ProvinceChina The First Clinical Medicine College Gansu University of Chinese MedicineLanzhou 730000Gansu ProvinceChina General Surgery Clinical Centre Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina The Second Department of General Surgery Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina Lanzhou University People's Clinical Hospital Lanzhou 730000Gansu ProvinceChina Gansu Research Center of Prevention and Control Project for Digestive Oncology Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina Gansu Key Laboratory of Molecular Diagnostics and Precision Medicine for Surgical Oncology Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina

Minimally invasive surgery is a kind of surgical operation,which is performed by using professional surgical instruments and equipment to inactivate,resect,repair or reconstruct the pathological changes,deformities and wounds in human body through micro-trauma or micro-approach,in order to achieve the goal of treatment,its surgical effect is equivalent to the traditional open surgery,while avoiding the morbidity of conventional surgical *** addition,it also has the advantages of less trauma,less blood loss during operation,less psychological burden and quick recovery on patients,and these minimally invasive techniques provide unique value for the examination and treatment of gastric cancer *** minimally invasive surgical techniques have developed rapidly and offer numerous options for the treatment of early gastric cancer(EGC):endoscopic mucosal resection(EMR),underwater EMR(UEMR),endoscopic submucosal dissection(ESD),endoscopic full-thickness resection(EFTR),endoscopic submu-cosal excavation(ESE),submucosal tunnel endoscopic resection,laparoscopic and endoscopic cooperative surgery(LECS);Among them,EMR,EFTR and LECS technologies have a wide range of applications and different modific-ations have been derived from their respective surgical operations,such as band-assisted EMR(BA-EMR),conven-tional EMR(CEMR),over-the-scope clip-assisted EFTR,no-touch EFTR,the inverted LECS,closed LECS,and so *** new and improved minimally invasive surgeries are more precise,specific and effective in treating different types of EGC.

关键词： Minimally invasive surgery Early gastric cancer Endoscopic mucosal resection Endoscopic full-thickness resection Laparoscopic and endoscopic cooperative surgery

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Reproducibility study of intravoxel incoherent motion and apparent diffusion coefficient parameters in normal pancreas

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 2031-2039页

作者： Xiang Liu yi-feng wang Xiao-Hui Qi Zhi-Lei Zhang Jiang-Yang Pan Xue-Li Fan Yu Du ying-Min Zhai Qi wang Department of CT and MRI The Fourth Hospital of Hebei Medical UniversityShijiazhuang 050000Hebei ProvinceChina

BACKGROUND The consistency of pancreatic apparent diffusion coefficient(ADC)values and intravoxel incoherent motion(IVIM)parameter values across different magnetic resonance imaging(MRI)devices significantly impacts the patient’s diagnosis and *** To explore consistency in image quality,ADC values,and IVIM parameter values among different MRI devices in pancreatic *** This retrospective study was approved by the local ethics committee,and informed consent was obtained from all *** total,22 healthy volunteers(10 males and 12 females)aged 24-61 years(mean,28.9±2.3 years)underwent pancreatic diffusion-weighted imaging using 3.0T MRI equipment from three *** independent observers subjectively scored image quality and measured the pancreas’s overall ADC values and signal-to-noise ratios(SNRs).Subsequently,regions of interest(ROIs)were delineated for the IVIM parameters(true diffusion coefficient,pseudo-diffusion coefficient,and perfusion fraction)using post-processing *** ROIs were on the head,body,and tail of the *** subjective image ratings were assessed using the kappa consistency *** correlation coefficients(ICCs)and mixed linear models were used to evaluate each device’s quantitative parameter ***,a pairwise analysis of IVIM parameter values across each device was performed using Bland-Altman *** The Kappa value for the subjective ratings of the different observers was 0.776(P0.05),and the ICCs for the ADC values from different devices were 0.870,0.707,and 0.808,respectively(P<0.05).Notably,only a few statistically significant inter-device agreements were observed for different IVIM parameters,and among t

关键词： Intravoxel incoherent motion Pancreas Image quality Consistency test

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基于电沉积技术制备ZnS量子点/海藻酸盐复合膜及其检测应用

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高分子学报 2024年第2期55卷 202-211页

作者：许泽泉陈炜唐靖陈宗明陶江涛李彦志王艺峰武汉理工大学材料科学与工程学院武汉430070

基于电沉积技术发展了一种原位制备ZnS量子点及其海藻酸盐复合膜的方法,此方法具备可控性好、步骤简单、条件温和、绿色环保等优点.实验结果表明,电沉积后可以在电极上形成ZnS量子点/海藻酸锌复合膜,该复合膜表面光滑无气泡,在302 nm紫... 详细信息

基于电沉积技术发展了一种原位制备ZnS量子点及其海藻酸盐复合膜的方法,此方法具备可控性好、步骤简单、条件温和、绿色环保等优点.实验结果表明,电沉积后可以在电极上形成ZnS量子点/海藻酸锌复合膜,该复合膜表面光滑无气泡,在302 nm紫外光下呈现清晰的蓝色荧光.透射电镜测试和光谱分析结果表明复合膜中存在ZnS量子点,其平均粒径为3.0 nm.利用电沉积技术的可控性和空间选择性以及ZnS量子点的荧光性能,可以制备出具备不同形状和荧光图案的复合膜.此外,利用电沉积技术制备的ZnS量子点/海藻酸锌复合膜同时具备荧光检测和电化学检测的能力,在双模式检测以及构建双模式检测器方面具备应用前景.

关键词：电沉积 ZnS量子点海藻酸盐电化学检测荧光检测

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C–F bond functionalizations of trifluoromethyl groups via radical intermediates

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Chinese Chemical Letters 2022年第3期33卷 1193-1198页

作者： Tesfaye Tebeka Simur Tian Ye You-Jie Yu feng-Lian Zhang yi-feng wang Department of Chemistry University of Science and Technology of ChinaHefei 230026China

Selective functionalization of C-F bonds in trifluoromethyl groups has recently received a growing interest, as it offers atom- and step-economic pathways to access highly valuable mono- and difluoroalkyl-substituted organic molecules using simple and inexpensive trifluoromethyl sources as the starting materials. In this regard, impressive progress has been made on the defluorinative functionalization reactions that proceed via radical intermediates. Nevertheless, it is still a great challenge to precisely control the defluorination process, due to the continuous decrease of the C-F bond strength after the replacement of one or two fluorine atoms with various functionalities. This review article is aimed to provide a brief overview of recently reported methods used to functionalize C-F bonds of CF_(3) groups via radical intermediates. An emphasis is placed on the discussion of mechanistic aspects and synthetic applications.

关键词： C–F bond functionalizations Radical intermediates Trifluoromethyl groups Difluorinated compounds Monofluorinated compounds

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4-Dimethylaminopyridine-Boryl Radical Promoted Monodefluorinative Alkylation of 3,3-Difluorooxindoles

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Chinese Journal of Chemistry 2022年第5期40卷 577-581页

作者： Tesfaye Tebeka Simur Fentahun Wondu Dagnaw You-Jie Yu feng-Lian Zhang yi-feng wang Hefei National Laboratory for Physical at the Microscale Department of ChemistryUniversity of Science and Technology of China96 Jinzhai RoadHefeiAnhui230026 China

A selective monodefluorinative alkylation of 3,3-difluorooxindoles is *** reaction starts by the attack of a 4-dimethylaminopyrine-boryl radical to the carbonyl oxygen atom of 3,3-difluorooxindoles,followed by a spin-center shift to generate radical intermediates with the elimination of a fluoride *** subsequent radical addition to alkenes affords a range of 3-alkyl-fluorooxindoles *** strategy offers access to C-3 functionalized oxindoles with wide substrate scope and tolerates a wide range of functional groups.

关键词： Radical reactions Alkylation I Fluorine Spin-center shift Defluorination

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Beam Training and Tracking in mmWave Communication:A Survey

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China Communications 2024年第6期21卷 1-22页

作者： wang yi Wei Zhiqing feng Zhiyong Yangtze Delta Region Institute(Quzhou) University of Electronic Science and Technology of ChinaQuzhou 324003China School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and TelecommunicationsBeijing 100876China

Communicating on millimeter wave(mmWave)bands is ushering in a new epoch of mobile communication which provides the availability of 10 Gbps high data rate ***,mmWave links are easily prone to short transmission range communication because of the serious free space path loss and the blockage by *** overcome these challenges,highly directional beams are exploited to achieve robust links by hybrid *** aligning the transmitter and receiver beams,*** training,is vitally important to high data rate ***,it may cause huge overhead which has negative effects on initial access,handover,and ***,the mobility patterns of users are complicated and dynamic,which may cause tracking error and large tracking *** efficient beam tracking method has a positive effect on sustaining robust *** article provides an overview of the beam training and tracking technologies on mmWave bands and reveals the insights for future research in the 6th Generation(6G)mobile ***,some open research problems are proposed to realize fast,accurate,and robust beam training and *** hope that this survey provides guidelines for the researchers in the area of mmWave communications.

关键词： 6G beam tracking beam training beamforming mmWave

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Coarse-fine joint target parameter estimation method based on AN-RSC in OFDM passive radar

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Journal of Systems Engineering and Electronics 2024年第2期35卷 339-349页

作者： wang Chujun WAN Xianrong yi Jianxin CHENG feng School of Electronic Information Wuhan UniversityWuhan 430072China

In this paper,we study the accuracy of delay-Doppler parameter estimation of targets in a passive radar using orthogonal frequency division multiplexing(OFDM)signal.A coarse-fine joint estimation method is proposed to achieve better estimation accuracy of target parameters without excessive computational ***,the modulation symbol domain(MSD)method is used to roughly estimate the delay and Doppler of ***,to obtain high-precision Doppler estimation,the atomic norm(AN)based on the multiple measurement vectors(MMV)model(MMV-AN)is used to manifest the signal sparsity in the continuous Doppler *** the same time,a reference signal compensation(RSC)method is presented to obtain highprecision delay *** results based on the OFDM signal show that the coarse-fine joint estimation method based on AN-RSC can obtain a more accurate estimation of target parameters compared with other *** addition,the proposed method also possesses computational advantages compared with the joint parameter estimation.

关键词： passive radar orthogonal frequency division multiplexing(OFDM)signal atomic norm(AN) parameter estimation

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An optimized numerical method to pre-researching the performance of solid-phase oxygen control in a non-isothermal lead–bismuth eutectic loop

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Nuclear Science and Techniques 2022年第3期33卷 77-88页

作者： Xiao-Bo Li Rui-Xian Liang yi-feng wang Hui-Ping Zhu Fang Liu Yang Liu Cong Li Hao Wu feng-Lei Niu School of Nuclear Science and Engineering North China Electric Power UniversityBeijing 102206China

In the present work,a new transient calculation method for parameters that can be used to evaluate the ability of oxygen control in a non-isothermal lead-bismuth eutectic(LBE)loop with solid-phase oxygen control was *** incorporates the dissolution process of PbO particles and the oxygen mass transfer process,and an optimized method was used for finding out the optimized oxygen mass transfer *** numerical terms,three mass transfer models were simultaneously applied,and comparisons of calculated and experimental results from the CRAFT loop indicated that the optimized calculation method and these new oxygen mass transfer models were correct and applicable to other LBE *** this calculation method,we aimed to optimize prediction of the distribution of oxygen and iron concentrations,time taken to establish the steady state of oxygen,and maximum dissolution/precipitation rates of corrosion products and corrosion depth across the entire LBE *** hope that this work will provide a potential reference for designing a more intelligent oxygen control system in the future.

关键词： LBE Solid-phase oxygen control Operating domain Operating model Corrosion depth Dissolution/precipitation

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Effect of rare earth on primary carbides in H13 die steel and their addition method:a review

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Journal of Iron and Steel Research(International) 2024年第3期31卷 531-551页

作者： Jing-feng wang Lin-zhu wang Chao-yi Chen Xiang wang Fei Zhao School of Materials and Metallurgy Guizhou UniversityGuiyang 550025GuizhouChina Zhengzhou Railway Vocational and Technical College Zhengzhou 450000HenanChina Guizhou Provincial University Key Laboratory of High Performance Battery Materials Guizhou UniversityGuiyang 550025GuizhouChina Shougang Guiyang Special Steel Co. Guiyang 550005GuizhouChina

Larger-sized primary carbides lead to stress concentration during the application of H13 hot-work die steel,resulting in microcracks and fatigue *** earth was usually added to modify the carbides and *** existing literature is reviewed on the effect of rare earth on primary carbides in H13 steel.A comprehensive review on the effect of rare earth on the characteristics of primary carbides,i.e.,number,size,morphology,and thermal stability in H13 steel,was *** precipitation mechanism and nucleation of primary carbides with rare earth were *** position and form of rare earth in steel and their effects on alloying elements segregation were *** addition techniques of rare earth in H13 steel were compared,and the prospects for other uncommon rare earth and emerging technology were *** on the current references,it can be known that adding rare earth facilitated refined and dispersed primary *** size of primary carbides would be reduced,and their morphology would be improved because the rare earth inclusions formed in H13 steel can act as nucleation cores forγ-Fe orδ-Fe,refining the dendritic ***,the number of primary carbides at grain boundaries would be significantly ***,rare earth had little impact on thermal *** nucleation of primary carbides tended to be inhibited due to the modification of inclusions by rare earth which were likely to be nucleation cores for primary *** earth had been reported to affect the mechanism and process of primary carbide ***,the addition of rare earth can inhibit the segregation of alloying elements and carbon diffusion by ***,laboratory experiments and theoretical calcu-lations need to be conducted to study the states and evolution of rare earth steels.

关键词： Rare earth H13 die steel Primary carbide Nucleation Dendritic structure

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Visible Light Indoor Positioning System Based on Pisarenko Harmonic Decomposition and Neural Network

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Chinese Journal of Electronics 2024年第1期33卷 195-203页

作者： Li ZHAO yi REN Qi wang Lange DENG feng ZHANG School of Electronic Information Engineering Xi’an Technological University

Visible-light indoor positioning is a new generation of positioning technology that can be integrated into smart lighting and optical communications. The current received signal strength(RSS)-based visible-light positioning systems struggle to overcome the interferences of background and indoor-reflected noise. Meanwhile, when ensuring the lighting, it is impossible to use the superposition of each light source to accurately distinguish light source information; furthermore, it is difficult to achieve accurate positioning in complex indoor environments. This study proposes an indoor positioning method based on a combination of power spectral density detection and a neural network. The system integrates the mechanism for visible-light radiation detection with RSS theory, to build a back propagation neural network model fitting for multiple reflection channels. Different frequency signals are loaded to different light sources at the beacon end, and the characteristic frequency and power vectors are obtained at the location end using the Pisarenko harmonic decomposition method. Then, a complete fingerprint database is established to train the neural network model and conduct location tests. Finally, the location effectiveness of the proposed algorithm is verified via actual positioning experiments. The simulation results show that, when four groups of sinusoidal waves with different frequencies are superimposed with white noise, the maximum frequency error is 0.104 Hz and the maximum power error is 0.0362 W. For the measured positioning stage, a 0.8 m × 0.8 m × 0.8 m solid wood stereoscopic positioning model is constructed, and the average error is 4.28 cm. This study provides an effective method for separating multi-source signal energies, overcoming background noise, and improving indoor visible-light positioning accuracies.

关键词： Neural networks Measurement uncertainty Position measurement Harmonic analysis Light emitting diodes Frequency estimation Indoor positioning systems

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