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Preoperatively predicting vessels encapsulating tumor clusters in hepatocellular carcinoma:machine learning model based on contrast-enhanced computed tomography

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 857-874页

作者： chao Zhang Hai Zhong Fang Zhao Zhen-Yu ma Zheng-jun Dai Guo-Dong Pang Department of Radiology The Second Hospital of Shandong UniversityJinan 250033Shandong ProvinceChina Department of Radiology Qilu Hospital of Shandong UniversityJinan 250014Shandong ProvinceChina Department of Radiology Linglong Yingcheng HospitalYantai 265499Shandong ProvinceChina Department of Scientific Research Huiying Medical Technology Co.LtdBeijing 100192China

BACKGROUND Recently,vessels encapsulating tumor clusters(VETC)was considered as a distinct pattern of tumor vascularization which can primarily facilitate the entry of the whole tumor cluster into the bloodstream in an invasion independent manner,and was regarded as an independent risk factor for poor prognosis in hepatocellular carcinoma(HCC).AIM To develop and validate a preoperative nomogram using contrast-enhanced computed tomography(CECT)to predict the presence of VETC+in HCC.METHODS We retrospectively evaluated 190 patients with pathologically confirmed HCC who underwent CECT scanning and immunochemical staining for cluster of differentiation 34 at two medical centers.Radiomics analysis was conducted on intratumoral and peritumoral regions in the portal vein phase.Radiomics features,essential for identifying VETC+HCC,were extracted and utilized to develop a radiomics model using machine learning algorithms in the training set.The model’s performance was validated on two separate test sets.Receiver operating characteristic(ROC)analysis was employed to compare the identified performance of three models in predicting the VETC status of HCC on both training and test sets.The most predictive model was then used to constructed a radiomics nomogram that integrated the independent clinical-radiological features.ROC and decision curve analysis were used to assess the performance characteristics of the clinical-radiological features,the radiomics features and the radiomics nomogram.RESULTS The study included 190 individuals from two independent centers,with the majority being male(81%)and a median age of 57 years(interquartile range:51-66).The area under the curve(AUC)for the combined radiomics features selected from the intratumoral and peritumoral areas were 0.825,0.788,and 0.680 in the training set and the two test sets.A total of 13 features were selected to construct the Rad-score.The nomogram,combining clinicalradiological and combined radiomics features could accurately predict VETC+in all three sets,with AUC

关键词： Hepatocellular carcinoma Vessels encapsulating tumor clusters Intratumoral and peritumoral regions Radiomics features Nomog

GRU-integrated constrained soft actor-critic learning enabled fully distributed scheduling strategy for residential virtual power plant

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Global Energy Interconnection 2024年第2期7卷 117-129页

作者： Xiaoyun Deng Yongdong Chen Dongchuan Fan Youbo Liu chao ma College of Electrical Engineering Sichuan UniversityChengdu 610065P.R.China State Grid Sichuan Comprehensive Energy Service Co.Ltd. Chengdu 610072P.R.China

In this study,a novel residential virtual power plant(RVPP)scheduling method that leverages a gate recurrent unit(GRU)-integrated deep reinforcement learning(DRL)algorithm is proposed.In the proposed scheme,the GRU-integrated DRL algorithm guides the RVPP to participate effectively in both the day-ahead and real-time markets,lowering the electricity purchase costs and consumption risks for end-users.The Lagrangian relaxation technique is introduced to transform the constrained markov decision process(CMDP)into an unconstrained optimization problem,which guarantees that the constraints are strictly satisfied without determining the penalty coefficients.Furthermore,to enhance the scalability of the constrained soft actor-critic(CSAC)-based RVPP scheduling approach,a fully distributed scheduling architecture was designed to enable plug-and-play in the residential distributed energy resources(RDER).Case studies performed on the constructed RVPP scenario validated the performance of the proposed methodology in enhancing the responsiveness of the RDER to power tariffs,balancing the supply and demand of the power grid,and ensuring customer comfort.

关键词： Residential virtual power plant Residential distributed energy resource Constrained soft actor-critic Fully distributed scheduling strategy

An adaptive energy regulation in a memristive map linearized from a circuit with two memristive channels

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Communications in Theoretical Physics 2024年第3期76卷 42-50页

作者： Feifei Yang Ping Zhou jun ma School of Science Chongqing University of Posts and TelecommunicationsChongqing 430065China College of Electrical and Information Engineering Lanzhou University of TechnologyLanzhou 730050China Department of Physics Lanzhou University of TechnologyLanzhou 730050China

Nonlinear circuits can show multistability when a magnetic flux-dependent memristor(MFDM) or a charge-sensitive memristor(CSM) is incorporated into a one branch circuit,which helps estimate magnetic or electric field effects.In this paper,two different kinds of memristors are incorporated into two branch circuits composed of a capacitor and a nonlinear resistor,thus a memristive circuit with double memristive channels is designed.The circuit equations are presented,and the dynamics in this oscillator with two memristive terms are discussed.Then,the memristive oscillator is converted into a memristive map by applying linear transformation on the sampled time series for the memristive oscillator.The Hamilton energy function for the memristive oscillator is obtained by using the Helmholtz theorem,and it can be mapped from the field energy of the memristive circuit.An energy function for the dual memristive map is suggested by imposing suitable weights on the discrete energy function.The dynamical behaviors of the new memristive map are investigated,and an adaptive law is proposed to regulate the firing mode in the memristive map.This work will provide a theoretical basis and experimental guidance for oscillator-to-map transformation and discrete map energy calculation.

关键词： Hamilton energy dual memristive map adaptive energy regulation

Optimized Auxiliary Frequency Control of Wind Farm Based on Piecewise Reduced-order Frequency Response Model

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 791-802页

作者： Xu Zhang Chen Zhao junchao ma Long Zhang Dan Sun Chenxu Wang Yan Peng Heng Nian the School of Electrical Engineering Zhejiang University Electric Power Research Institute of State Grid Zhejiang Electric Power Corporation

With the increasing wind power penetration in the power system, the auxiliary frequency control(AFC) of wind farm(WF) has been widely used. The traditional system frequency response(SFR) model is not suitable for the wind power generation system due to its poor accuracy and applicability. In this paper, a piecewise reduced-order frequency response(PROFR) model is proposed, and an optimized auxiliary frequency control(O-AFC) scheme of WF based on the P-ROFR model is proposed. Firstly, a full-order frequency response model considering the change in operating point of wind turbine is established to improve the applicability. In order to simplify the fullorder model, a P-ROFR model with second-order structure and high accuracy at each frequency response stage is proposed. Based on the proposed P-ROFR model, the relationship between the frequency response indexes and the auxiliary frequency controller coefficients is expressed explicitly. Then, an OAFC scheme with the derived explicit expression as the optimization objective is proposed in order to improve the frequency support capability on the premise of ensuring the full release of the rotor kinetic energy and the full use of the effect of time delay on frequency regulation. Finally, the effectiveness of the proposed P-ROFR model and the performance of the proposed OAFC scheme are verified by simulation studies.

关键词： Frequency control Frequency response Rotors Analytical models Indexes Optimization Delay effects

Two simple memristive maps with adaptive energy regulation ano digital signal process verification

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第5期25卷 382-394页

作者： Feifei YANG Lujie REN jun ma Zhigang ZHU College of Electrical and Information Engineering Lanzhou University of TechnologyLanzhou 730050China Department of Physics Lanzhou University of TechnologyLanzhou 730050China School of Information Science and Engineering Dalian Polytechnic UniversityDalian 116034China

mathematical models can produce desired dynamics and statistical properties with the insertion of suitable nonlinear terms,while energy characteristics are crucial for practical application because any hardware realizations of nonlinear systems are relative to energy flow.The involvement of memristive terms relative to memristors enables multistability and initial-dependent property in memristive systems.In this study,two kinds of memristors are used to couple a capacitor or an inductor,along with a nonlinear resistor,to build different neural circuits.The corresponding circuit equations are derived to develop two different types of memristive oscillators,which are further converted into two kinds of memristive maps after linear transformation.The Hamilton energy function for memristive oscillators is obtained by applying the Helmholz theorem or by mapping from the field energy of the memristive circuits.The Hamilton energy functions for both memristive maps are obtained by replacing the gains and discrete variables for the memristive oscillator with the corresponding parameters and variables.The two memristive maps have rich dynamic behaviors including coherence resonance under noisy excitation,and an adaptive growth law for parameters is presented to express the self-adaptive property of the memristive maps.A digital signal process(DSP)platform is used to verify these results.Our scheme will provide a theoretical basis and experimental guidance for oscillator-to-map transformation and discrete map-energy calculation.

关键词： Hamilton energy Discrete memristor Self-adaptive regulation Digital signal process(DSP)implementation

Memristive oscillator to memristive map,energy characteristic

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Science China(Technological Sciences) 2024年第5期67卷 1567-1578页

作者： GUO YiTong ma jun ZHANG XiaoFeng HU XiKui College of Electrical and Information Engineering Lanzhou University of TechnologyLanzhou730050China Department of Physics Lanzhou University of TechnologyLanzhou730050China School of Science Chongqing University of Posts and TelecommunicationsChongqing400065China

Most of nonlinear oscillators composed of capacitive and inductive variables can obtain the Hamilton energy by using the Helmholtz theorem when the models are rewritten in equivalent vector forms.The energy functions for biophysical neurons can be obtained by applying scale transformation on the physical field energy in their equivalent neural circuits.Realistic dynamical systems often have exact energy functions,while some mathematical models just suggest generic Lyapunov functions,and the energy function is effective to predict mode transition.In this paper,a memristive oscillator is approached by two kinds of memristor-based nonlinear circuits,and the energy functions are defined to predict the dependence of oscillatory modes on energy level.In absence of capacitive variable for capacitor,the physical time t and charge q are converted into dimensionless variables by using combination of resistance and inductance(L,R),e.g.,τ=t×R/L.Discrete energy function for each memristive map is proposed by applying the similar weights as energy function for the memristive oscillator.For example,energy function for the map is obtained by replacing the variables and parameters of the memristive oscillator with corresponding variables and parameters for the memristive map.The memristive map prefers to keep lower average energy than the memristive oscillator,and chaos is generated in a discrete system with two variables.The scheme is helpful for energy definition in maps,and it provides possible guidance for verifying the reliability of maps by considering the energy characteristic.

关键词： Hamilton energy memristor Helmholtz theorem scale transformation memristive circuit

Diagnostic performance of dynamic contrast-enhanced magnetic resonance imaging parameters and serum tumor markers in rectal carcinoma prognosis

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1796-1807页

作者： Ren-Qi Mu jun-Wei Lv Cai-Yun ma Xiao-Hui ma Dong Xing Hou-Sheng ma Department of Radiology Yantai Mountain HospitalYantai 264001Shandong ProvinceChina Department of Radiology Yantai Yuhuangding HospitalYantai 264000Shandong ProvinceChina Department of Gynaecology Yantai Yuhuangding HospitalYantai 264000Shandong ProvinceChina The First Clinical Medical College Xinjiang Medical UniversityUrumqi 830011Xinjiang Uygur Autonomous RegionChina

BACKGROUND Rectal carcinoma(RC),one of the most common malignancies globally,presents an increasing incidence and mortality year by year,especially among young people,which seriously affects the prognosis and quality of life of patients.At present,dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)parameters and serum carbohydrate antigen 19-9(CA19-9)and CA125 Levels have been used in clinical practice to evaluate the T stage and differentiation of RC.However,the accuracy of these evaluation modalities still needs further research.This study explores the application and value of these methods in evaluating the T stage and differentiation degree of RC.AIM To analyze the diagnostic performance of DCE-MRI parameters combined with serum tumor markers(TMs)in assessing pathological processes and prognosis of RC patients.METHODS A retrospective analysis was performed on 104 RC patients treated at Yantai Yuhuangding Hospital from may 2018 to January 2022.Patients were categorized into stages T1,T2,T3,and T4,depending on their T stage and differentiation degree.In addition,they were assigned to low(L group)and moderate-high differentiation(M+H group)groups based on their differentiation degree.The levels of DCE-MRI parameters and serum CA19-9 and CA125 in different groups of patients were compared.In addition,the value of DCE-MRI parameters[volume transfer constant(Ktrans),rate constant(Kep),and extravascular extracellular volume fraction(Ve)in assessing the differentiation and T staging of RC patients was discussed.Furthermore,the usefulness of DCE-MRI parameters combined with serum CA19-9 and CA125 Levels in the evaluation of RC differentiation and T staging was analyzed.RESULTS Ktrans,Ve,CA19-9 and CA125 were higher in the high-stage group and L group than in the low-stage group and M+H Group,respectively(P<0.05).The areas under the curve(AUCs)of the Ktran and Ve parameters were 0.638 and 0.694 in the diagnosis of high and low stages,respectively,and 0.672 and 0.725 in diagnosing moderate-high and low differe

关键词： Rectal carcinoma Volume transfer constant Rate constant Extravascular extracellular volume fraction Serum carbohydrate antigen 19-9 Serum carbohydrate antigen 125

A progressive framework for rotary motion deblurring

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Defence Technology（防务技术） 2024年第2期32卷 159-172页

作者： Jinhui Qin Yong ma jun Huang Fan Fan You Du School of Electronic Information Wuhan UniversityWuhan430072China

The rotary motion deblurring is an inevitable procedure when the imaging seeker is mounted in the rotating missiles.Traditional rotary motion deblurring methods suffer from ringing artifacts and noise,especially for large blur extents.To solve the above problems,we propose a progressive rotary motion deblurring framework consisting of a coarse deblurring stage and a refinement stage.In the first stage,we design an adaptive blur extents factor(BE factor)to balance noise suppression and details reconstruction.And a novel deconvolution model is proposed based on BE factor.In the second stage,a triplescale deformable module CNN(TDM-CNN)is designed to reduce the ringing artifacts,which can exploit the 2D information of an image and adaptively adjust spatial sampling locations.To establish a standard evaluation benchmark,a real-world rotary motion blur dataset is proposed and released,which includes rotary blurred images and corresponding ground truth images with different blur angles.Experimental results demonstrate that the proposed method outperforms the state-of-the-art models on synthetic and real-world rotary motion blur datasets.The code and dataset are available at https://***/JinhuiQin/RotaryDeblurring.

关键词： Rotary motion deblurring Progressive framework Blur extents factor TDM-CNN

Overview of the immunological mechanisms in hepatitis B virus reactivation:Implications for disease progression and management strategies

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World Journal of Gastroenterology 2024年第10期30卷 1295-1312页

作者： Hui ma Qing-Zhu Yan Jing-Ru ma Dong-Fu Li jun-Ling Yang Department of Clinical Laboratory The Second Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina Department of Ultrasound Medicine The Second Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina Digestive Diseases Center Department of Hepatopancreatobiliary MedicineThe Second Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina Department of Respiratory and Critical Care Medicine The Second Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina

Hepatitis B virus(HBV)reactivation is a clinically significant challenge in disease management.This review explores the immunological mechanisms underlying HBV reactivation,emphasizing disease progression and management.It delves into host immune responses and reactivation’s delicate balance,spanning innate and adaptive immunity.Viral factors’disruption of this balance,as are interac-tions between viral antigens,immune cells,cytokine networks,and immune checkpoint pathways,are examined.Notably,the roles of T cells,natural killer cells,and antigen-presenting cells are discussed,highlighting their influence on disease progression.HBV reactivation’s impact on disease severity,hepatic flares,liver fibrosis progression,and hepatocellular carcinoma is detailed.management strategies,including anti-viral and immunomodulatory approaches,are critically analyzed.The role of prophylactic anti-viral therapy during immunosuppressive treatments is explored alongside novel immunotherapeutic interventions to restore immune control and prevent reactivation.In conclusion,this compre-hensive review furnishes a holistic view of the immunological mechanisms that propel HBV reactivation.With a dedicated focus on understanding its implic-ations for disease progression and the prospects of efficient management stra-tegies,this article contributes significantly to the knowledge base.The more profound insights into the intricate interactions between viral elements and the immune system will inform evidence-based approaches,ultimately enhancing disease management and elevating patient outcomes.The dynamic landscape of management strategies is critically scrutinized,spanning anti-viral and immunomodulatory approaches.The role of prophylactic anti-viral therapy in preventing reactivation during immunosuppressive treatments and the potential of innovative immunotherapeutic interventions to restore immune control and proactively deter reactivation.

关键词： Hepatitis B virus reactivation Immunological mechanisms Disease progression management strategies Immune response