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Contribution to the Full 3D Finite Element Modelling of a Hybrid Stepping Motor with and without Current in the Coils

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journal of Electromagnetic Analysis and Applications 2024年第2期16卷 11-23页

作者： Belemdara Dingamadji Hilaire mbaïnaïbeye j.rôme Guidkaya Golam Department of Physics and Engineering Sciences University of N&#8217Djamena N&#8217Djamena Chad Department of Physics University of Moundou Moundou Chad Department of Physics University of Ngaoundere Ngaoundere Cameroon

The paper presents our contribution to the full 3D finite element modelling of a hybrid stepping motor using COMSOL Multiphysics software. This type of four-phase motor has a permanent magnet interposed between the two identical and coaxial half stators. The calculation of the field with or without current in the windings (respectively with or without permanent magnet) is done using a mixed formulation with strong coupling. In addition, the local high saturation of the ferromagnetic material and the radial and axial components of the magnetic flux are taken into account. The results obtained make it possible to clearly observe, as a function of the intensity of the bus current or the remanent induction, the saturation zones, the lines, the orientations and the magnetic flux densities. 3D finite element modelling provide more accurate numerical data on the magnetic field through multiphysics analysis. This analysis considers the actual operating conditions and leads to the design of an optimized machine structure, with or without current in the windings and/or permanent magnet.

关键词： Modelling 3D Finite Elements Magnetic Flux Hybrid Stepping Motor

Analysis of mid-spatial frequency wavefront distortions from a liquid-cooled flash-lamp pumped Nd:phosphate laser amplifier

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High Power Laser Science and Engineering 2024年第1期12卷 24-29页

作者： Pierre-Marie Dalbies Sandy Cavaro Edouard Bordenave nathalie Blanchot julien G.Moreau j.rôme Neauport CEA CESTA Le BarpFrance

Mid-spatial frequency wavefront deformation can be deleterious for the operation of high-energy laser systems. When fluid cooled high-repetition-rate amplifiers are used, the coolant flow is likely to induce such detrimental mid-spatial frequency wavefront deformations. Here, we describe the design and performance of a 90 mm × 90 mm aperture, liquid-cooled Nd:phosphate split-slab laser amplifier pumped by flash-lamps. The performance of the system is evaluated in terms of wavefront aberration and gain at repetition rates down to 1 shot per minute. The results show that this single cooled split-slab system exhibits low wavefront distortions in the medium to large period range, compatible with a focus on target, and despite the use of liquid coolant traversed by both pump and amplified wavelengths. This makes it a potential candidate for applications in large high-energy laser facilities.

关键词： flash-lamp pumping high-power laser laser cooling neodymium glass wavefront error

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Antimicrobial resistance containment in Africa:Moving beyond surveillance

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Biosafety and Health 2024年第1期6卷 50-58页

作者： Zikora Kizito Glory Anyaegbunam Ifeanyi Elibe mba Yandev Doowuese Ngozi j.Anyaegbunam Toluwalase mba Fetuata Aminat Aina Vincent NnamdigadiChigor Emeka Innocent Nweze Emmanuel A.Ezea Department of Microbiology Faculty of Biological SciencesUniversity of Nigeria Nsukka CampusEnugu 410001Nigeria Department of Pharmaceutical Microbiology Faculty of PharmacyUniversity of IbadanIbadan 20005Nigeria Department of Microbiology Federal University of Health SciencesOtukpo 970001Nigeria measurement and Evaluation Unit Science Education Department University of Nigeria NsukkaEnugu 410001Nigeria Sumy State University Medical InstituteSumy Oblast 40000Ukraine Lead City University Hospital Lead CityIbadan 200255Nigeria Department of Microbiology College of Natural SciencesFederal University of AgricultureAbeokuta 111101Nigeria

Worldwide,infections caused by drug‐resistant pathogens constitute a significant challenge threatening therapeutic *** to the World Health Organization(WHO),antimicrobial resistance(AMr)ranks among the top 10 global public health *** with a high rate of multiple host adaptivity,significant genetic diversity(multiple lineages),high virulence factors,and genetic exchange have been isolated from various sources(humans,animals,and the environment)even without exposure to prior *** now,the source of AMr and how resistant clones are selected in the environment remain largely elusive,and potential anthropogenic transmission has been reported in different *** drug‐resistant pathogens,lineages,resistant clones,outbreak clusters,plasmid replicates,and genes that play a critical role in resistance dissemination have been *** of certain multidrug‐resistant(MDr)determinants has also been shown to enhance or support the propagation of *** far,significant advances have been made in understanding the burden of ***,overcoming AMr requires a holistic approach,as there is no single approach with sufficient precision to curb the *** strengthening AMr surveillance efforts is essential,as we have shown,there is also a need to intensify efforts to strengthen therapeutic interventions,especially in priority regions such as ***,we discussed the burden of AMr and the dissemination of AMr in humans,animals,and the environment(non‐medical drivers).We further delved into the big questions on Africa and discussed how therapeutic interventions involving vaccines and other viable biomaterials could be pivotal in reducing the burden of AMr to the barest minimum.

关键词： Antimicrobial resistance(AMr) Bacteria Surveillance One Health Vaccines Africa

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Lax-Oleinik-Type Formulas and Efficient Algorithms for Certain High-Dimensional Optimal Control Problems

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Communications on Applied Mathematics and Computation 2024年第2期6卷 1428-1471页

作者： Paula Chen j.rome Darbon Tingwei meng Division of Applied Mathematics Brown UniversityProvidenceRIUSA Department of Mathematics UCLALos AngelesCAUSA

Two of the main challenges in optimal control are solving problems with state-dependent running costs and developing efficient numerical solvers that are computationally tractable in high *** this paper,we provide analytical solutions to certain optimal control problems whose running cost depends on the state variable and with constraints on the *** also provide Lax-Oleinik-type representation formulas for the corresponding Hamilton-jacobi partial differential equations with state-dependent ***,we present an efficient,grid-free numerical solver based on our representation formulas,which is shown to scale linearly with the state dimension,and thus,to overcome the curse of *** existing optimization methods and the min-plus technique,we extend our numerical solvers to address more general classes of convex and nonconvex initial *** demonstrate the capabilities of our numerical solvers using implementations on a central processing unit(CPU)and a field-programmable gate array(FPGA).In several cases,our FPGA implementation obtains over a 10 times speedup compared to the CPU,which demonstrates the promising performance boosts FPGAs can *** numerical results show that our solvers have the potential to serve as a building block for solving broader classes of high-dimensional optimal control problems in real-time.

关键词： Optimal control Hamilton-jacobi partial differential equations Grid-free numerical methods High dimensions Field-programmable gate arrays(FPGAs)

role of aminopeptidase N-like in the acquisition of begomoviruses by Bemisia tabaci,the whitefly vector

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Insect Science 2024年第3期31卷 707-719页

作者： Yun-Yun Fan Yao Chi na Chen Wilmer j.Cuellar Xiao-Wei Wang Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insects Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang ProvinceInstitute of Insect SciencesZhejiang UniversityHangzhouChina Zhejiang Tianmushan national nature reserve Administration HangzhouChina Institute of Plant Protection Liaoning Academy of Agricultural SciencesShenyangChina Virology Laboratory Cassava ProgramInternational Center for Tropical Agriculture(CIAT)PalmiraColombia

Sri Lankan cassava mosaic virus(SLCMV)is a prominent causative agent of cassava mosaic disease in Asia and relies on the whitefly Bemisia tabaci cryptic complex for its ***,the molecular mechanisms involved in SLCMV transmission by *** have yet to be *** this study,we identified an aminopeptidase N-like protein(BtAPN)in *** Asia II 1,an efficient vector of SLCMV,which is involved in the SLCMV transmission *** the use of glutathione S-transferase pull-down assay and LC-MS/MS analysis,we demonstrated the interaction between BtAPN and the coat protein(CP)of *** interaction was further confirmed in vitro,and we observed an induction of BtAPN gene expression following SLCMV *** interfering with the function of BtAPN,the quantities of SLCMV were significantly reduced in various parts of *** Asia II 1,including the whole body,midgut,hemolymph,and primary salivary ***,we discovered that BtAPN is conserved in *** Middle East-Asia Minor 1(meAM1)and interacts with the CP of tomato yellow leaf curl virus(TYLCV),a begomovirus known to cause severe damage to tomato *** BtAPN with antibody led to a significant reduction in the quantities of TYLCV in whitefly whole body and organs/*** results demonstrate that BtAPN plays a generic role in interacting with the CP of begomoviruses and positively regulates their acquisition by the whitefly.

关键词： BtAPN coat protein SLCMV TYLCV virus acquisition whitefly

Survey on Fake Information Generation,Dissemination and Detection

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Chinese journal of Electronics 2024年第3期33卷 573-583页

作者： Wanqiu CUI Dawei WANG na HAN School of national Security People's Public Security University of China Big Data Center of The Ministry of Public Security

The current booming development of the Internet has put the public in an era of information overload,in which false information is mixed and spread *** phenomenon has seriously disturbed the social network ***,a substantial amount of research is beginning to be devoted to the effective management of fake *** analyze the abnormal characteristics of fake information from its mechanism of generation and *** view of different exceptional features,we systematically sort out and evaluate the existing studies on false content *** commonly used public datasets,metrics,and performance are categorized and compared,hoping to provide a basis and guidance for related *** study found that the current active social platforms show different *** future direction should point to mining platform features of multi-domain sources,multi-data forms,and multi-language heterogeneity to provide more valuable clues for fake information.

关键词： Fake information Abnormal characteristics Detection methods Public datasets

Effect of La on the Corrosion Behavior and mechanism of 3Ni Weathering Steel in a Simulated Marine Atmospheric Environment

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Acta metallurgica Sinica(English Letters) 2024年第2期37卷 308-324页

作者： Gang Niu rui Yuan r.D.K.Misra na Gong Zhi-Hui Zhang Hao-Xiu Chen Hui-Bin Wu Cheng-jia Shang Xin-Ping Mao Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing100083China Laboratory for Excellence in Advanced Steel research Department of MetallurgicalMaterials and Biomedical EngineeringUniversity of Texas at El PasoEl PasoTX79968USA Institute of Materials research and Engineering Agency for ScienceTechnologyand ResearchSingapore138634Singapore Department of Materials Science and Engineering University of TorontoTorontoONM5S 3E4Canada

The corrosion behavior and mechanism of 3Ni weathering steel in a simulated oceanic atmospheric environment are investigated in order to comprehend the impacts of La,as determined through electrochemical analysis and rust layer *** results of this study demonstrate that the addition of La enhances the corrosion resistance of 3Ni weathering steel in the marine atmospheric environment,thereby reducing the corrosion rate and improving the protection of the rust *** influence of La on corrosion resistance can be attributed to two primary ***,La functions as a grain refiner,minimizing the potential difference of the micro-regions on the substrate surface,thereby significantly reducing the corrosion of bare steel in the marine ***,La inhibits the process of Fe_(3)O_(4) oxidation back toγ-FeOOH during corrosion at the local site,thus decreasing the formation ofγ-FeOOH and enhancing the charge transfer *** research work may serve as a reference for expanding the application of rare earth elements in the field of weathering steel.

关键词： Weathering steel rare earth rust layer Corrosion behavior Corrosion resistance

Oxygen tension modulates cell function in an in vitro three-dimensional glioblastoma tumor model

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Bio-Design and Manufacturing 2024年第3期7卷 307-319页

作者： Sen Wang Siqi Yao na Pei Luge Bai Zhiyan Hao Dichen Li jiankang He j.Miguel Oliveira Xiaoyan Xue Ling Wang Xinggang Mao State Key Laboratory for Manufacturing System Engineering Xi’an Jiaotong UniversityXi’an 710054China School of mechanical Engineering Xi’an Jiaotong UniversityXi’an 710054China NMPA Key Laboratory for research and Evaluation of Additive Manufacturing medical Devices Xi’an Jiaotong UniversityXi’an 710054China 3B’s research Group I3Bs–Research Institute on BiomaterialsBiodegradables and BiomimeticsUniversity of MinhoHeadquarters of the European Institute of Excellence on Tissue Engineering and Regenerative MedicineAveParkZona Industrial da Gandra4805-017 BarcoGuimarãesPortugal ICVS/3B’s-PT Government Associate Laboratory 4806-909 Braga/Guimar˜aesPortugal Department of Pharmacology School of PharmacyFourth Military Medical UniversityXi’an 710032China Department of Neurosurgery Xijing HospitalFourth Military Medical UniversityXi’an 710032China

Hypoxia is a typical feature of the tumor microenvironment,one of the most critical factors affecting cell behavior and tumor ***,the lack of tumor models able to precisely emulate natural brain tumor tissue has impeded the study of the effects of hypoxia on the progression and growth of tumor *** study reports a three-dimensional(3D)brain tumor model obtained by encapsulating U87MG(U87)cells in a hydrogel containing type I *** also documents the effect of various oxygen concentrations(1%,7%,and 21%)in the culture environment on U87 cell morphology,proliferation,viability,cell cycle,apoptosis rate,and ***,it compares two-dimensional(2D)and 3D *** comparison purposes,cells cultured in flat culture dishes were used as the control(2D model).Cells cultured in the 3D model proliferated more slowly but had a higher apoptosis rate and proportion of cells in the resting phase(G0 phase)/gap I phase(G1 phase)than those cultured in the 2D ***,the two models yielded significantly different cell ***,hypoxia(e.g.,1%O2)affected cell morphology,slowed cell growth,reduced cell viability,and increased the apoptosis rate in the 3D *** results indicate that the constructed 3D model is effective for investigating the effects of biological and chemical factors on cell morphology and function,and can be more representative of the tumor microenvironment than 2D culture *** developed 3D glioblastoma tumor model is equally applicable to other studies in pharmacology and pathology.

关键词： Hypoxia Glioma Three-dimensional glioma model In vitro

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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