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Influence of laser parameters on the microstructures and surface properties in laser surface modification of biomedical magnesium alloys

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Journal of Magnesium and Alloys 2024年第1期12卷 72-97页

作者： Chee ying Tan Cuie Wen Hua Qian Ang School of Engineering RMIT UniversityMelbourneVictoria 3001Australia

Biodegradable implants from magnesium(Mg)alloys have emerged in the biomedical field especially in the orthopedic and cardiovascular stent applications owing to their low density,high specific strength,excellent machinability,good biocompatibility,and *** primary shortcoming of Mg-based implants is their low corrosion resistance in the physiological environment,which results in premature mechanical integrity loss before adequate healing and the production of excessive hydrogen gas,which is harmful to the body tissues and negatively affects the biocompatibility of the *** surface modification has recently received attention because it can improve the surface properties such as surface chemistry,roughness,topography,corrosion resistance,wear resistance,hydrophilicity,and thus cell response to the surface of the *** composition and microstructures including textures and phases of laser-treated surfaces depend largely on the laser processing parameters(input laser power,laser scan velocity,frequency,pulse duration,pressure,gas circulation,working time,spot size,beam focal position,and laser track overlap)and the thermophysical properties of the substrate(solubility,melting point,and boiling point).This review investigates the impacts of various laser surface modification techniques including laser surface melting,laser surface alloying,laser cladding,laser surface texturing,and laser shock peening,and highlights their significance in improving the surface properties of biodegradable Mg alloys for implant ***,we explore how different laser process parameters affect its composition,microstructure,and surface properties in each laser surface modification technique.

关键词： Biocompatibility Biodegradability Corrosion Implant applications Laser surface modification Magnesium alloys

Surface modification by ligand growth strategy for dense copper bismuth film as photocathode to enhance hydrogen production activity

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Frontiers in Energy 2024年第1期18卷 89-100页

作者： Zhouzhou WANG Qingwei WU Jieming WANG ying YU Institute of Nanoscience and Nanotechnology College of Physical Science and TechnologyCentral China Normal UniversityWuhan 430079China

Hydrogen production from photoelectrochemical(PEC)water splitting has been regarded as a promising way to utilize renewable and endless solar ***,semiconductor film grown on photoelectrode suffers from numerous challenges,leading to the poor PEC ***,a straightforward sol-gel method with the ligand-induced growth strategy was employed to obtain dense and homogeneous copper bismuthate photocathodes for PEC hydrogen evolution *** various characterizations,it was found that the nucleation and surface growth of CuBi_(2)O_(4)layer induced by 2-methoxyethanol ligand(2-CuBi_(2)O_(4))demonstrated a decent crystallinity and coverage,as well as a large grain size and a low oxygen vacancy concentration,leading to the good ability of light absorption and carrier ***,under simulated sunlight irradiation(AM1.5G,100 mW/cm^(2)),the 2-CuBi_(2)O_(4)photocathode achieved an enhanced photocurrent density of−1.34 mA·cm^(−2)at 0.4 V versus the reversible hydrogen electrode and a promising applied bias photon-to-current efficiency of 0.586%.This surface modification by ligand growth strategy will shed light on the future design of advanced photoelectrodes for PEC water splitting.

关键词： copper bismuthate photocathode ligand growth strategy dense film PEC

Path-Following Control With Obstacle Avoidance of Autonomous Surface Vehicles Subject to Actuator Faults

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 956-964页

作者： Li-ying Hao Gege Dong Tieshan Li Zhouhua Peng the School of Marine Electrical Engineering Dalian Maritime UniversityDalian 116026China the School of Automation Engineering University of Electronic Science and Technology of ChinaChengdu 611731the Navigation CollegeDalian Maritime UniversityDalian 116026 the Yangtze Delta Region Institute(Huzhou) Huzhou 313001China

This paper investigates the path-following control problem with obstacle avoidance of autonomous surface vehicles in the presence of actuator faults,uncertainty and external *** surface vehicles inevitably suffer from actuator faults in complex sea environments,which may cause existing obstacle avoidance strategies to *** reduce the influence of actuator faults,an improved artificial potential function is constructed by introducing the lower bound of actuator efficiency *** nonlinear state observer,which only depends on measurable position information of the autonomous surface vehicle,is used to address uncertainties and external *** using a backstepping technique and adaptive mechanism,a path-following control strategy with obstacle avoidance and fault tolerance is designed which can ensure that the tracking errors converge to a small neighborhood of *** with existing results,the proposed control strategy has the capability of obstacle avoidance and fault tolerance ***,the comparison results through simulations are given to verify the effectiveness of the proposed method.

关键词： Actuator faults autonomous surface vehicle(ASVs) improved artificial potential function nonlinear state observer obstacle avoidance

Threshold Selection and Resource Allocation for Quantized Identification

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Journal of Systems Science & Complexity 2024年第1期37卷 204-229页

作者： WANG ying LI Xin ZHAO Yanlong ZHANG Ji-Feng Key Laboratory of Systems and Control Institute of Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

This paper is concerned with the optimal threshold selection and resource allocation problems of quantized identification, whose aims are improving identification efficiency under limited resources. Firstly, the first-order asymptotically optimal quantized identification theory is extended to the weak persistent excitation condition. Secondly, the characteristics of time and space complexities are established based on the Cramér-Rao lower bound of quantized systems. On these basis, the optimal selection methods of fixed thresholds and adaptive thresholds are established under aperiodic signals, which answer how to achieve the best efficiency of quantized identification under the same time and space complexity. In addition, based on the principle of maximizing the identification efficiency under a given resource, the optimal resource allocation methods of quantized identification are given for the cases of fixed thresholds and adaptive thresholds, respectively, which show how to balance time and space complexity to realize the best identification efficiency of quantized identification.

关键词： Quantized output resource allocation system identification threshold selection.

Parallel intelligent education with ChatGPT

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Frontiers of Information Technology & Electronic Engineering 2024年第1期25卷 12-18页

作者： Jiacun WANG ying TANG Ryan HARE Fei-Yue WANG Department of Computer Science and Software Engineering Monmouth UniversityNew Jersey 07764USA Department of Electrical and Computer Engineering Rowan UniversityNew Jersey 08028USA Institute of Automation Chinese Academy of SciencesBeijing 100190China

This paper presents a framework for parallel intelligent education that involves physical and virtual learning for a personalized learning *** especially focus on Chat Generative Pre-trained Transformer(ChatGPT)owing to its considerable potential to supplement regular class *** address the strengths and weaknesses of learning with ***,we discuss the challenges and solutions of the proposed parallel intelligent education with ChatGPT.

关键词： education GPT intelligent

Computed tomography-based radiomics diagnostic approach for differential diagnosis between early-and late-stage pancreatic ductal adenocarcinoma

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1256-1267页

作者： Shuai Ren Li-Chao Qian ying-ying Cao Marcus J Daniels Li-Na Song ying Tian Zhong-Qiu Wang Department of Radiology Jiangsu Province Hospital of Chinese MedicineAffiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina Department of Geratology Nanjing Hospital of Chinese Medicine Affiliated to Nanjing University of Chinese MedicineNanjing 210022Jiangsu ProvinceChina Department of Radiology NYU Langone HealthNew YorkNY 10016United States

BACKGROUND One of the primary reasons for the dismal survival rates in pancreatic ductal adenocarcinoma(PDAC)is that most patients are usually diagnosed at late *** is an urgent unmet clinical need to identify and develop diagnostic methods that could precisely detect PDAC at its earliest *** A total of 71 patients with pathologically proved PDAC based on surgical resection who underwent contrast-enhanced computed tomography(CT)within 30 d prior to surgery were included in the *** staging was performed in accordance with the 8th edition of the American Joint Committee on Cancer staging *** features were extracted from the region of interest(ROI)for each patient using Analysis Kit *** most important and predictive radiomics features were selected using Mann-Whitney U test,univar-iate logistic regression analysis,and minimum redundancy maximum relevance(MRMR)*** forest(RF)method was used to construct the radiomics model,and 10-times leave group out cross-validation(LGOCV)method was used to validate the robustness and reproducibility of the *** A total of 792 radiomics features(396 from late arterial phase and 396 from portal venous phase)were extracted from the ROI for each patient using Analysis Kit *** most important and predictive features were selected using Mann-Whitney U test,univariate logistic regression analysis,and MRMR *** method was used to construct the radiomics model with the nine most predictive radiomics features,which showed a high discriminative ability with 97.7%accuracy,97.6%sensitivity,97.8%specificity,98.4%positive predictive value,and 96.8%negative predictive *** radiomics model was proved to be robust and reproducible using 10-times LGOCV method with an average area under the curve of 0.75 by the average performance of the 10 newly built *** The radiomics model based on CT could serve as a promising non-invasive method in differential diag

关键词： Pancreatic ductal adenocarcinoma Radiomics Computed tomography American Joint Committee on Cancer staging

Tumor-associated telocytes

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Chinese Medical Journal 2024年第4期137卷 490-492页

作者： Jinqing Zhang ying Xu Department of General Surgery Shandong Provincial Third HospitalShandong UniversityJinanShandong 250117China

To the Editor:It has been eighteen years since telocytes(TCs)were first categorized by Popescu et al^([1])in *** were classified into interstitial cells of the Cajal(ICC)type based on their ultrastructure and immunohistochemical features,which are similar to mesenchymal cells.^([2])In the following ten years,TCs were found to have their own distinctive characteristics in terms of three-dimensional structure,immunological biomarkers,genomics,and multiple ***,TCs are definitely distinct from fibroblasts,mesenchymal stem cells,and endothelial cells in multiple organs of human beings and animals.^([3])

关键词： cytes organs definitely

DDI-Transform:A neural network for predicting drug-drug interaction events

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Quantitative Biology 2024年第2期12卷 155-163页

作者： Jiaming Su ying Qian School of Computer Science and Technology Shanghai Frontiers Science Center of Molecule Intelligent SynthesesEast China Normal UniversityShanghaiChina

Drug-drug interaction(DDI)event prediction is a challenging problem,and accurate prediction of DDI events is critical to patient health and new drug ***,many machine learning-based techniques have been proposed for predicting DDI ***,most of the existing methods do not effectively integrate the multidimensional features of drugs and provide poor mitigation of noise to get effective feature *** address these limitations,we propose a DDI-Transform neural network framework for DDI event *** DDI-Transform,we design a drug structure information feature extraction module and a drug bind-protein feature extraction module to obtain multidimensional feature information.A stack of DDI-Transform layers in the DDI-Transform network module are then used for adaptive learning,thus adaptively selecting the effective feature information for *** results show that DDI-Transform can accurately predict DDI events and outperform the state-of-the-art *** on different scale datasets confirm the robustness of the method.

关键词： adaptive learning graph convolutional networks interaction prediction meta-path

Meromorphic Functions Sharing Two Values

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Wuhan University Journal of Natural Sciences 2024年第1期29卷 7-12页

作者： ZHAO ying HUANG Zhigang School of Mathematical Sciences Suzhou University of Science and TechnologySuzhou 215009JiangsuChina

Let f and g be two nonconstant meromorphic functions,and n be a positive *** f^(n)(z)and g^(n)(z)share 1 CM(counting multiplicities),f(z)and g(z)share∞IM(ignoring multiplicities),and N(r,1f)+N(r,1g)=S(r,f)+S(r,g),then either f(z)≡tg(z)or f(z)g(z)≡t,where t^(n)=*** an application,shared values problems of a meromorphic function related to its shifts and difference operators are also investigated.

关键词： meromorphic function shared values difference operator shift