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Noninvasive Characterization of Metabolic Changes in Ischemic Stroke Using Z-spectrum-fitted Multiparametric Chemical Exchange Saturation Transfer-weighted Magnetic Resonance Imaging

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Current Medical Science 2023年第5期43卷 970-978页

作者： zhen-xiong WANG Xin-hua WEI Ke-jia CAI wen-zhen zhu Chang-liang SU Department of Radiology Guangzhou First People’s HospitalSchool of MedicineSouth China University of TechnologyGuangzhou 510180China Department of Radiology Department of Bioengineeringand The Center for MR ResearchUniversity of Illinois at ChicagoChicago 60612USA Department of Radiology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Radiology Sun Yat-sen University Cancer CenterState Key Laboratory of Oncology in South ChinaCollaborative Innovation Center for Cancer MedicineGuangzhou 510060China

Objective This study aimed to noninvasively characterize the metabolic alterations in ischemic brain tissues using Z-spectrum-fitted multiparametric chemical exchange saturation transfer-weighted magnetic resonance imaging(CEST-MRI).Methods Three sets of Z-spectrum data with saturation power(B_(1))values of 1.5,2.5,and 3.5µT,respectively,were acquired from 17 patients with ischemic *** contrasts contributing to the Z-spectrum,including fitted amide proton transfer(APT_(fitted)),+2 ppm peak(CEST@2ppm),concomitantly fitted APT_(fitted) and CEST@2ppm(APT&CEST@2ppm),semisolid magnetization transfer contrast(MT),aliphatic nuclear Overhauser effect(NOE),and direct saturation of water(DSW),were fitted with 4 and 5 Lorentzian functions,*** CEST metrics were compared between ischemic lesions and contralateral normal white matter(CNWM),and the correlation between the CEST metrics and the apparent diffusion coefficient(ADC)was *** differences in the Z-spectrum metrics under varied B1 values were also *** Ischemic lesions showed increased APTfitted,CEST@2ppm,APT&CEST@2ppm,NOE,and DSW as well as decreased ***&CEST@2ppm,MT,and DSW showed a significant correlation with ADC[APT&CEST@2ppm at the 3 B_(1) values:R=0.584/0.467/0.551;MT at the 3 B_(1) values:R=−0.717/−0.695/−0.762(4-parameter fitting),R=−0.734/−0.711/−0.785(5-parameter fitting);DSW of 4-/5-parameter fitting:R=0.794/0.811(2.5µT),R=0.800/0.790(3.5µT)].However,the asymmetric analysis of amide proton transfer(APT_(asym))could not differentiate the lesions from CNWM and showed no correlation with ***,the Z-spectrum contrasts varied with B_(1).Conclusion The Z-spectrum-fitted multiparametric CEST-MRI can comprehensively detect metabolic alterations in ischemic brain tissues.

关键词： chemical exchange saturation transfer Z-spectrum ischemic stroke

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Reducing Operation Emissions and Improving Work Efficiency Using a Pure Electric Wheel Drive Tractor

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Engineering 2024年第6期37卷 230-245页

作者： Chang-Kai wen wen Ren Qing-zhen zhu Chun-Jiang Zhao zhen-Hao Luo Sheng-Li Zhang Bin Xie Zhi-Jun Meng Research Center of Intelligent Equipment Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China State Key Laboratory of Intelligent Agricultural Power Equipment Beijing 100097China BYD Company Limited Shenzhen 518118China College of Agricultural Engineering Jiangsu UniversityZhenjiang 212013China College of Engineering China Agricultural UniversityBeijing 100083China

In response to the problems of excessive greenhouse-gas and particulate emissions and the low traction efficiency of conventional diesel tractors in the field,a purely electric wheel-side drive tractor was studied,including an electric motor drive system,a battery ballast system,and an electro–hydraulic suspension *** paper develops a dynamics model of an electric tractor-ploughing unit under complex soil conditions,leading to the proposal of an active control method for drive wheel torque and a joint control method for the traction force of the suspension system and the front-and rear-axle loads of a ***,the tractor is prototyped and assembled,and ploughing tests are carried *** ploughing results show that the active torque-distribution control method proposed in this study reduces the tractor slip by 14.83%and increases the traction efficiency by 10.28%compared with the average torquedistribution *** with the conventional traction control mode,the joint control method for traction and ballast proposed in this paper results in a 3.7%increase in traction efficiency,a 15.05%decrease in slip,and a 4.9%reduction in total drive motor energy *** study will help to improve the operation quality and traction efficiency of electric tractors in complex soil conditions.

关键词： Electric tractor Ploughing unit Torque distribution Active ballast Traction performance

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The combined detection of carcinoembryonic antigen,carcinogenic antigen 125,and carcinogenic antigen 19-9 in colorectal cancer patients

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 2073-2079页

作者： Ling-zhen Gong Qian-wen Wang Jie-wen zhu Department of Clinical Laboratory Huangshi Central Hospital(Affiliated Hospital of Hubei Polytechnic University)Hubei Key Laboratory of Kidney Disease Pathogenesis and InterventionHuangshi Tumor Molecular Diagnosis and Treatment Key LaboratoryHuangshi 435000Hubei ProvinceChina

BACKGROUND Hepatic metastases are common and difficult to treat after colorectal cancer(CRC)*** predictive value of carcinoembryonic antigen(CEA),cancer antigen(CA)125 and CA19-9 combined tests for liver metastasis is *** To evaluate predictive value of combined tests for CEA,CA125,and CA19-9 levels in patients with liver metastases of *** The retrospective study included patients with CRC alone(50 cases)and patients with CRC combined with liver metastases(50 cases)who were hospitalized between January 2021 and January *** CEA,CA125 and CA19-9 levels were compared between the two groups,and binary logistic regression was used to analyze the predictive value of the combination of these tumor markers in liver *** addition,we performed receiver operating characteristic(ROC)curve analysis to assess its diagnostic *** The results showed that the serum CEA,CA125 and CA19-9 levels in the CRC with liver metastasis group were significantly higher than those in the CRC alone ***,the average serum CEA level in the CRC with liver metastasis group was 162.03±810.01 ng/mL,while that in the CRC alone group was 5.71±9.76 ng/mL;the average serum CA125 levels were 43.47±83.52 U/mL *** 13.5±19.68 U/mL;the average serum CA19-9 levels were 184.46±473.13 U/mL and 26.55±43.96 U/mL *** addition,binary logistic regression analysis showed that CA125 was significant in predicting CRC liver metastasis(P<0.05).ROC curve analysis results showed that the areas under the ROC curves of CEA,CA125 and CA19-9 were 0.607,0.692 and *** These results suggest that combined detection of these tumor markers may help early detection and intervention of CRC liver metastasis,thereby improving patient prognosis.

关键词： Colorectal cancer Liver metastasis Serum markers Carcinoembryonic antigen Cancer antigen 125 Cancer antigen 19-9 Receiver operating characteristic analysis

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A Comparative Study Between Tumor Blood Vessels and Dynamic Contrast-enhanced MRI for Identifying Isocitrate Dehydrogenase Gene 1(IDH1)Mutation Status in Glioma

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Current Medical Science 2022年第3期42卷 650-657页

作者： Shi-hui LI Nan-xi SHEN Di WU Ju ZHANG Jia-xuan ZHANG Jing-jing JIANG wen-zhen zhu Department of Radiology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Objective Isocitrate dehydrogenase gene(IDH)mutations are associated with tumor angiogenesis and therefore play an important role in glioma *** study compared the performance of tumor blood vessels counted from contrast-enhanced 3D brain volume(3D-BRAVO)sequence and dynamic contrast-enhanced(DCE)MRI in differentiating IDH1 status in *** Forty-four glioma patients[16 with IDH1 mutant-type(IDH1-MT),28 with IDH1 wild-type(IDH1-WT)]were retrospectively analyzed.A blood vessel entering a tumor was defined as an intratumoral vessel;a blood vessel adjacent to the edge of a tumor was defined as a peritumoral *** vessels were defined as the sum of the intratumoral and peritumoral ***-derived metrics of tumor were normalized to the contralateral normal-appearing white *** Intratumoral,peritumoral,and combined tumor blood vessels were all significantly different between IDH1-MT and IDH1-WT gliomas,and the range of area under curves(AUCs)was 0.816–*** DCE-derived parameters,cerebral blood volume,cerebral blood flow,mean transit time,and volume transfer constant were significantly different between IDH1-MT and IDH1-WT gliomas,and the range of AUCs was 0.703–*** vessels possessed the best performance for identifying IDH1 mutations in gliomas(AUC:0.855,sensitivity:0.857,specificity:0.812,P<0.001).Conclusion The number of tumor blood vessels has comparable diagnostic performance with DCE-derived parameters for differentiating IDH1 mutations and can serve as a potential imaging biomarker to reflect IDH1 mutations in gliomas.

关键词： dynamic contrast-enhanced perfusion glioma isocitrate dehydrogenase gene tumor blood vessel

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Sequential reactant water management by complementary multisite catalysts for surpassing platinum hydrogen evolution activity

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Nano Research 2024年第3期17卷 1232-1241页

作者： Yu Lin Defang Ding Shicheng zhu Qunlei wen Huangjingwei Li zhen Li Youwen Liu Yi Shen China Engineering Research Center of Nano-Geomaterials of Ministry of Education Faculty of Materials Science and ChemistryChina University of GeosciencesWuhan 430078China State Key Laboratory of Materials Processing and Die&Mould Technology and School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

Alkaline hydrogen evolution reaction(HER)offers a near-zero-emission approach to advance hydrogen ***,the activity limited by the multiple reaction steps involving H_(2)O molecules transfer,absorption,and activation still unqualified the thresholds of economic ***,we proposed a multisite complementary strategy that incorporates hydrophilic Mo and electrophilic V into Ni-based catalysts to divide the distinct steps on atomically dispersive sites and thus realize sequential regulation of the HER *** Isotopic labeled in situ Raman spectroscopy describes 4-coordinated hydrogen bonded H_(2)O to be free H_(2)O passing the inner Helmholtz plane in the vicinity of the catalysts under the action of hydrophilic Mo ***,potential-dependent electrochemical impedance spectroscopy(EIS)reveals that electrophilic V sites with abundant 3d empty orbitals could activate the lone-pair electrons in the free H_(2)O molecules to produce more protic hydrogen,and dimerize into H_(2) at the Ni *** the sequential management of reactive H_(2)O molecules,NiMoV oxides multisite catalysts surpass Pt/C hydrogen evolution activity(49 mV@10 mA∙cm^(-2) over 140 h).Profoundly,this study provides a tangible model to deepen the comprehension of the catalyst–electrolyte interface and create efficient catalysts for diverse reactions.

关键词： hydrogen evolution activity complementary multisite catalysts sequential reactive water management interfacial water molecules

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Optimization design of the hydro-pneumatic suspension system for high clearance self-propelled sprayer using improved MOPSO algorithm

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 109-122页

作者： Fan Yang Yuefeng Du Changkai wen zhen Li Enrong Mao Zhongxiang zhu College of Engineering China Agricultural UniversityBeijing 100083China Beijing Key Laboratory of Optimized Design for Modern Agricultural Equipment China Agricultural UniversityBeijing 100083China

Large high clearance self-propelled sprayers were widely used in field plant protection due to their high-efficiency operation *** by the characteristics of field operations such as high power,heavy weight,high ground clearance,and fast operation speed,the comprehensive requirements for the ride comfort,handling stability and road friendliness of the sprayer were increasingly *** the present stage,the chassis structure of the high clearance selfpropelled sprayer that attaches great importance to the improvement of comprehensive performance still has the problems of severe bumps,weak handling performance and serious road damage in complex field ***,this paper proposes an optimization design method for hydro-pneumatic suspension system of a high clearance self-propelled sprayer based on the improved MOPSO(Multi-Objective Particle Swarm Optimization)algorithm,covering the entire process of configuration design,parameter intelligent optimization,and system verification of the high clearance self-propelled sprayer ***,chassis structure of the hydro-pneumatic suspension suitable for the high clearance self-propelled sprayer was designed,and a design method combining the improved MOPSO algorithm based on time-varying fusion strategy and adaptive update with the parameter optimization of hydro-pneumatic suspension based on this algorithm was proposed,and finally the software simulation and bench performance verification were carried *** results show that the optimized hydropneumatic suspension has excellent vibration reduction effect,and the body acceleration,suspension dynamic deflection and tire deflection were increased by 16.5%,9.9%and 0.9%respectively,compared with those before *** comprehensive performance of the hydro-pneumatic suspension designed in this study is better than that of the traditional suspension.

关键词： high clearance self-propelled sprayer vibration reduction hydro-pneumatic suspension MOPSO multi-objective optimization

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For LEO Satellite Networks: Intelligent Interference Sensing and Signal Reconstruction Based on Blind Separation Technology

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China Communications 2024年第2期21卷 85-95页

作者： Chengjie Li Lidong zhu zhen Zhang The Key Laboratory for Computer Systems of State Ethnic Affairs Commission School of Computer Science and Technology(Southwest Minzu University)Chengdu 610000China National Key Laboratory of Science and Technology on Communications(University of Electronic Science and Technology of China) Chengdu 610000China College of Computer Science(Sichuan University) Chengdu 610000China

In LEO satellite communication networks,the number of satellites has increased sharply, the relative velocity of satellites is very fast, then electronic signal aliasing occurs from time to time. Those aliasing signals make the receiving ability of the signal receiver worse, the signal processing ability weaker,and the anti-interference ability of the communication system lower. Aiming at the above problems, to save communication resources and improve communication efficiency, and considering the irregularity of interference signals, the underdetermined blind separation technology can effectively deal with the problem of interference sensing and signal reconstruction in this scenario. In order to improve the stability of source signal separation and the security of information transmission, a greedy optimization algorithm can be executed. At the same time, to improve network information transmission efficiency and prevent algorithms from getting trapped in local optima, delete low-energy points during each iteration process. Ultimately, simulation experiments validate that the algorithm presented in this paper enhances both the transmission efficiency of the network transmission system and the security of the communication system, achieving the process of interference sensing and signal reconstruction in the LEO satellite communication system.

关键词： blind source separation greedy optimization algorithm interference sensing LEO satellite communication networks signal reconstruction

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Quantitative Measurement of Cerebral Perfusion with Intravoxel Incoherent Motion in Acute Ischemia Stroke： Initial Clinical Experience

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Chinese Medical Journal 2015年第19期128卷 2565-2569页

作者： Li-Bao Hu Nan Hong wen-zhen zhu Department of Radiology Peking University People's HospitalBeijing 100044China Department of Radiology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei 430030China

Background：Intravoxel incoherent motion （IVIM） has the potential to provide both diffusion and perfusion information without an exogenous contrast agent,its application for the brain is promising,however,feasibility studies on this are relatively *** aim of this study is to assess the feasibility of IVIM perfusion in patients with acute ischemic stroke （AIS）.Methods：Patients with suspected AIS were examined by magnetic resonance imaging within 24 h of symptom *** patients （mean age was 68.7 ± 8.0 years） who underwent arterial spin labeling （ASL） and diffusion-weighted imaging （DWI） were identified as having AIS with ischemic penumbra were enrolled,where ischemic penumbra referred to the mismatch areas of ASL and *** different b-values were applied in the biexponential *** of interest were selected in ischemic penumbras and contralateral normal brain *** apparent diffusion coefficients （ADCs） and ASL cerebral blood flow （CBF） were *** paired t-test was applied to compare ASL CBF,fast ADC,and slow ADC measurements between ischemic penumbras and contralateral normal brain *** regression and Pearson＇s correlation were used to evaluate the correlations among quantitative ***：The fast ADCs and ASL CBFs of ischemic penumbras were significantly lower than those of the contralateral normal brain regions （1.93 ± 0.78 μm2/ms vs.3.97 ± 2.49 μm2/ms,P =0.007;13.5 ± 4.5 ml· 100 g-1 ·min-1 vs.29.1 ± 12.7 ml·100 g-1 ·min-1,P ＜ 0.001,respectively）.No significant difference was observed in slow ADCs between ischemic penumbras and contralateral normal brain regions （0.203 ± 0.090 μm2/ms vs.0.198 ± 0.100 μm2/ms,P =0.451）.Compared with contralateral normal brain regions,both CBFs and fast ADCs decreased in ischemic penumbras while slow ADCs remained the same.A significant correlation was detected between fast ADCs and ASL CBFs （r =0.416,P ＜ 0.05）.No statistically significant correlation was observed between ASL CB

关键词： Arterial Spin Labeling Cerebral Blood Flow Intravoxel Incoherent Motion Ischemic Penumbra

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Unmanned Aerial Vehicle Inspection Routing and Scheduling for Engineering Management

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Engineering 2024年第5期36卷 223-239页

作者： Lu zhen Zhiyuan Yang Gilbert Laporte wen Yi Tianyi Fan School of Management Shanghai UniversityShanghai 200444China Department of Decision Sciences HEC MontréalMontréalQC H3T 2A7Canada School of Management University of BathBath BA27AYUK Department of Building and Real Estate The Hong Kong Polytechnic UniversityHong Kong 999077China

Technological advancements in unmanned aerial vehicles(UAVs)have revolutionized various industries,enabling the widespread adoption of UAV-based *** engineering management,UAV-based inspection has emerged as a highly efficient method for identifying hidden risks in high-risk construction environments,surpassing traditional inspection *** on this foundation,this paper delves into the optimization of UAV inspection routing and scheduling,addressing the complexity introduced by factors such as no-fly zones,monitoring-interval time windows,and multiple monitoring *** tackle this challenging problem,we propose a mixed-integer linear programming(MILP)model that optimizes inspection task assignments,monitoring sequence schedules,and charging *** comprehensive consideration of these factors differentiates our problem from conventional vehicle routing problem(VRP),leading to a mathematically intractable model for commercial solvers in the case of large-scale *** overcome this limitation,we design a tailored variable neighborhood search(VNS)metaheuristic,customizing the algorithm to efficiently solve our *** numerical experiments are conducted to validate the efficacy of our proposed algorithm,demonstrating its scalability for both large-scale and real-scale *** experiments and a case study based on an actual engineering project are also conducted,providing valuable insights for engineering managers to enhance inspection work efficiency.

关键词： Engineering management Unmanned aerial vehicle Inspection routing and scheduling optimization Mixed-integer linear programming model Variable neighborhood search metaheuristic

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UAV-assisted cooperative offloading energy efficiency system for mobile edge computing

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Digital Communications and Networks 2024年第1期10卷 16-24页

作者： Xue-Yong Yu wen-Jin Niu Ye zhu Hong-Bo zhu Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and Telecommunications Nanjing210003China Engineering Research Centerof Health Service System Based on Ubiquitous Wireless Networks Ministry of EducationNanjng Universityof Posts and Telecommunications Nanjing210003China

Reliable communication and intensive computing power cannot be provided effectively by temporary hot spots in disaster areas and complex terrain ground *** this has greatly developed the application and integration of UAV and Mobile Edge Computing(MEC)to the Internet of Things(loT).However,problems such as multi-user and huge data flow in large areas,which contradict the reality that a single UAV is constrained by limited computing power,still *** to allowing UAV collaboration to accomplish complex tasks,cooperative task offloading between multiple UAVs must meet the interdependence of tasks and realize parallel processing,which reduces the computing power consumption and endurance pressure of *** the computing requirements of the user terminal,delay constraint of a computing task,energy constraint,and safe distance of UAV,we constructed a UAV-Assisted cooperative offloading energy efficiency system for mobile edge computing to minimize user terminal energy ***,the resulting optimization problem is originally nonconvex and thus,difficult to solve *** tackle this problem,we developed an energy efficiency optimization algorithm using Block Coordinate Descent(BCD)that decomposes the problem into three convex ***,we jointly optimized the number of local computing tasks,number of computing offloaded tasks,trajectories of UAV,and offloading matching relationship between multi-UAVs and multiuser *** results show that the proposed approach is suitable for different channel conditions and significantly saves the user terminal energy consumption compared with other benchmark schemes.

关键词： Computation offloading Internet of things(IoT) Mobile edge computing(MEC) Block coordinate descent(BCD)

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