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Differences between lower extremity joint running kinetics captured by marker-based and markerless systems were speed dependent

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Journal of Sport and Health Science 2024年第4期13卷 569-578页

作者： hui Tang Barry Munkasy li li Department of Health Sciences and Kinesiology Georgia Southern UniversityStatesboroGA 30458USA Department of Kinesiology and Health Education University of Texas at AustinAustinTX 78712USA

Background:The development of computer vision technology has enabled the use of markerless movement tracking for biomechanical *** research has reported the feasibility of markerless systems in motion analysis but has yet to fully explore their utility for capturing faster movements,such as *** studies using markerless systems in clinical and sports settings are still ***,the present study compared running biomechanics estimated by marker-based and markerless *** running speed not only affects sports performance but is also associated with clinical injury prevention,diagnosis,and rehabilitation,we aimed to investigate the effects of speed on the comparison of estimated lower extremity joint moments and powers between markerless and marker-based technologies during treadmill running as a concurrent validating ***:Kinematic data from marker-based/markerless technologies were collected,along with ground reaction force data,from 16 young adults running on an instrumented treadmill at 3 speeds:2.24 m/s,2.91 m/s,and 3.58 m/s(5.0 miles/h,6.5 miles/h,and 8.0 miles/h).Sagittal plane moments and powers of the hip,knee,and ankle were calculated by inverse dynamic *** series analysis and statistical parametric mapping were used to determine system ***:Compared to the marker-based system,the markerless system estimated increased lower extremity joint kinetics with faster speed during the swing phase in most ***:Despite the promising application of markerless technology in clinical settings,systematic markerless overestimation requires focused *** on segment pose estimations,the centers of mass estimated by markerless technologies were farther away from the relevant distal joint centers,which led to greater joint moments and powers estimates by markerless ***-based *** differences were amplified by running speed.

关键词： Biomechanics Motion capture Gait Statistical parametric mapping

Higher-order expansions of powered extremes of logarithmic general error distribution

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 47-54页

作者： TAN Xiao-feng li li-hui School of Mathematics and Statistics Southwest UniversityChongqing 400715China

In this paper,Let M_(n)denote the maximum of logarithmic general error distribution with parameter v≥***-order expansions for distributions of powered extremes M_(n)^(p)are derived under an optimal choice of normalizing *** is shown that M_(n)^(p),when v=1,converges to the Frechet extreme value distribution at the rate of 1/n,and if v>1 then M_(n)^(p)converges to the Gumbel extreme value distribution at the rate of(loglogn)^(2)=(log n)^(1-1/v).

关键词： logarithmic general error distribution convergence rate higher-order expansion powered ex-treme

Layered niobium carbide enabling excellent kinetics and cycling stability of li-Mg-B-H hydrogen storage material Layered niobium carbide enabling excellent kinetics

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Rare Metals 2024年第3期43卷 1153-1166页

作者： li-Wen Lu hui Luo Guang-Xu li Yun li Xin-Hua Wang Cun-Ke Huang Zhi-QiangLan Wen-Zheng Zhou Jin Guo Mohammad Ismail Hai-Zhen liu Guangxi Novel Battery Materials Research Center of Engineering Technology Guangxi Colleges and Universities Key Laboratory of Blue Energy and Systems IntegrationSchool of Physical Science and TechnologyGuangxi UniversityNanning530004China State Key Laboratory of Featured Metal Materials and life-Cycle Safety for Composite Structures Nanning530004China School of Mechanical and Electrical Engineering Quzhou College of TechnologyQuzhou324000China Department of Materials Science and Engineering Zhejiang UniversityHangzhou310027China Faculty of Ocean Engineering Technology and Informatics Universiti Malaysia Terengganu21030Kuala NerusTerengganuMalaysia Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin300071China

The li-Mg-B-H composite(2liBH_(4)+MgH_(2))has a high capacity of 11.4 wt%as a hydrogen storage ***,the slow kinetics and poor cycling stability severely restrict its practical *** this work,a layered Nb_(2)C MXene was first synthesized and then introduced to tailor the kinetics and cycling stability of the li-Mg-B-H *** milled 2liH+MgB_(2)composites were initially hydrogenated to obtain the 2liBH_(4)+MgH_(2)*** 2liBH_(4)+MgH_(2)+5wt%Nb_(2)C can release 9.0 wt%H_(2)in 30 min at 400℃,while it is only 2.7 wt%for the undoped 2liBH_(4)+MgH_(2).The dehydrogenation activation energies of MgH_(2)and liBH_(4)are 123 and 154 kJ·mol^(-1)respectively for the 5 wt%Nb_(2)C-doped composite,lower than the undoped composite(164 and 165 kJ·mol^(-1)).The 2liBH_(4)+MgH_(2)+5 wt%Nb_(2)C possesses excellent cycling stability,with the reversible capacity only slightly reduced from 9.4 wt%for the 1st cycle to 9.3 wt%for the 20th ***_(2)C keeps stable in the composite and acts as an efficient catalyst for the li-Mg-B-H *** is believed that both the layered structure and the active Nb element contribu te to the enhanced hydrogen storage performances of the li-Mg-B-H *** work confirms that the Nb_(2)C MXene with layered stru cture has a significant enhancing impact on the li-Mg-B-H hydrogen storage materials,which is different from the bulk NbC.

关键词： Hydrogen storage lithium borohydride Magnesium hydride Nb_(2)C MXene

Effect of boundary conditions on shakedown analysis of heterogeneous materials

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 39-68页

作者： Xiuchen GONG Yinghao NIE Gengdong CHENG kai li State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentInternational Research Center for Computational MechanicsDepartment of Engineering MechanicsDalian University of TechnologyDalian 116023Liaoning ProvinceChina

The determination of the ultimate load-bearing capacity of structures made of elastoplastic heterogeneous materials under varying loads is of great importance for engineering analysis and design. Therefore, it is necessary to accurately predict the shakedown domains of these materials. The static shakedown theorem, also known as Melan's theorem, is a fundamental method used to predict the shakedown domains of structures and materials. Within this method, a key aspect lies in the construction and application of an appropriate self-equilibrium stress field(SSF). In the structural shakedown analysis, the SSF is typically constructed by governing equations that satisfy no external force(NEF) boundary conditions. However, we discover that directly applying these governing equations is not suitable for the shakedown analysis of heterogeneous materials. Researchers must consider the requirements imposed by the Hill-Mandel condition for boundary conditions and the physical significance of representative volume elements(RVEs). This paper addresses this issue and demonstrates that the sizes of SSFs vary under different boundary conditions, such as uniform displacement boundary conditions(DBCs), uniform traction boundary conditions(TBCs), and periodic boundary conditions(PBCs). As a result, significant discrepancies arise in the predicted shakedown domain sizes of heterogeneous materials. Built on the demonstrated relationship between SSFs under different boundary conditions, this study explores the conservative relationships among different shakedown domains, and provides proof of the relationship between the elastic limit(EL) factors and the shakedown loading factors under the loading domain of two load vertices. By utilizing numerical examples, we highlight the conservatism present in certain results reported in the existing literature. Among the investigated boundary conditions, the obtained shakedown domain is the most conservative under ***, utilizing PBCs to

关键词： heterogeneous material self-equilibrium stress field(SSF) shakedown analysis effect of boundary conditions

Rheum palmatum L. and Salvia miltiorrhiza Bge. Alleviates Acute Pancreatitis by Regulating Th17 Cell Differentiation: An Integrated Network Pharmacology Analysis, Molecular Dynamics Simulation and Experimental Validation

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Chinese Journal of Integrative Medicine 2024年第5期30卷 408-420页

作者： FENG Min-chao LUO Fang HUANG liang-jiang li kai CHEN Zu-min li hui YAO Chun QIN Bai-jun CHEN Guo-zhong The First Clinical Medical College Guangxi University of Traditional Chinese MedicineNanning 530000China Guangxi Key Laboratory of Molecular Biology of Traditional Chinese Medicine and Preventive Medicine Nanning 530000China Graduate School Guangxi University of Traditional Chinese MedicineNanning 530000China Department of Gastroenterology the First Affiliated Hospital of Guangxi University of Traditional Chinese MedicineNanning 530023China

Objective: To identify the core targets of Rheum palmatum L. and Salvia miltiorrhiza Bge.,(Dahuang-Danshen, DH-DS) and the mechanism underlying its therapeutic efficacy in acute pancreatitis(AP)using a network pharmacology approach and validate the findings in animal experiments. Methods: Network pharmacology analysis was used to elucidate the mechanisms underlying the therapeutic effects of DH-DS in AP. The reliability of the results was verified by molecular docking simulation and molecular dynamics ***, the results of network pharmacology enrichment analysis were verified by immunohistochemistry,Western blot analysis and real-time quantitative PCR, respectively. Results: Sixty-seven common targets of DH-DS in AP were identified and mitogen-activated protein kinase 3(MAPK3), Janus kinase 2(JAK2), signal transducer and activator of transcription 3(STAT3), protein c-Fos(FOS) were identified as core targets in the protein interaction(PPI) network analysis. Gene ontology analysis showed that cellular response to organic substance was the main functions of DH-DS in AP, and Kyoto Encyclopedia of Genes and Genomes analysis showed that the main pathway included Th17 cell differentiation. Molecular docking simulation confirmed that DH-DS binds with strong affinity to MAPK3, STAT3 and FOS. Molecular dynamics simulation revealed that FOS-isotanshinone Ⅱ and STAT3-dan-shexinkum d had good binding capacity. Animal experiments indicated that compared with the AP model group, DH-DS treatment effectively alleviated AP by inhibiting the expression of interleukin-1β, interleukin-6 and tumor necrosis factor-α, and blocking the activation of Th17 cell differentiation(P<0.01). Conclusion: DH-DS could inhibit the expression of inflammatory factors and protect pancreatic tissues,which would be functioned by regulating Th17 cell differentiation-related m RNA and protein expressions.

关键词： Rheum palmatum L. Salvia miltiorrhiza Bge. molecular docking simulation network pharmacology acute pancreatitis Th17 cell differentiation

Motion Planning for Autonomous Driving with Real Traffic Data Validation

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 74-86页

作者： Wenbo Chu kai Yang Shen li Xiaolin Tang Western China Science City Innovation Center of Intelligent and Connected Vehicle Chongqing 400044China College of Mechanical and Vehicle Engineering Chongqing UniversityChongqing 400044China School of Civil Engineering Tsinghua UniversityBeijing 100084China

Accurate trajectory prediction of surrounding road users is the fundamental input for motion planning,which enables safe autonomous driving on public *** this paper,a safe motion planning approach is proposed based on the deep learning-based trajectory prediction *** begin with,a trajectory prediction model is established based on the graph neural network(GNN)that is trained utilizing the INTERACTION ***,the validated trajectory prediction model is used to predict the future trajectories of surrounding road users,including pedestrians and *** addition,a GNN prediction model-enabled motion planner is developed based on the model predictive control ***,two driving scenarios are extracted from the INTERACTION dataset to validate and evaluate the effectiveness of the proposed motion planning approach,i.e.,merging and roundabout *** results demonstrate that the proposed method can lower the risk and improve driving safety compared with the baseline method.

关键词： Trajectory prediction Graph neural network Motion planning INTERACTION dataset

Effect of SARS-CoV-2 infection on semen parameters in sperm bank volunteers with normal sperm concentration

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Asian Journal of Andrology 2024年第3期26卷 328-332页

作者： li Wang Wen-kai Han Xiao-hui Song Qi-lin Zhang An-Quan Guan Yuan Gao Jin-Long Ma Center for Reproductive Medicine Shandong UniversityJinan 250001China State Key Laboratory of Reproductive Medicine and Offspring Health ShandongUniversityJinan 250001China Key Laboratory of Reproductive Endocrinology of Ministry of Education Shandong UniversityJinan 250001China Shandong KeyLaboratory of Reproductive Medicine Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinan 250001China Shandong Provincial Clinical Research Center for Reproductive Health Jinan 250001China Shandong Technology Innovation Center for Reproductive Health Jinan 250001China NationalResearch Center for Assisted Reproductive Technology and Reproductive Genetics Shandong UniversityJinan 250001China Research Unit of Gametogenesis andHealth of ART-Offspring Chinese Academy of Medical Sciences(No.2021RU001)Jinan 250001China

In this study,we aimed to assess the effect of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection on *** study comprised 110 sperm volunteers who self-reported SARS-CoV-2 infection from the Human Sperm Bank ofthe Center for Reproductive Medicine,Shandong University(Jinan,China).The volunteers had normal sperm concentration *** volunteer provided semen samples before and after *** selected 90 days after infection as the cutoff *** parameters within 90 days after infection of 109 volunteers(group A)were compared with semen parameters before ***,semen parameters on or after 90 days after infection of 36 volunteers(group B)were compared with semen parameters ***,based on whether the volunteers had completed the three-dose SARS-CoV-2 vaccination booster,volunteersin group A and B were further divided into two subgroups *** parameters were compared before and after infection ineach *** results showed that in this cohort population,the semen quality in volunteers with normal sperm concentrationsbefore infection decreased after SARS-CoV-2 infection within 90 days,while the semen quality returned to preinfection levels after *** completion of a three-dose SARS-CoV-2 vaccination booster may exert a protective effect on semen quality after infection.

关键词： SARS-CoV-2 SARS-CoV-2 vaccination semen quality sperm donation sperm parameters

Random Forest-Based Fatigue Reliability-Based Design Optimization for Aeroengine Structures

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 665-684页

作者： Xue-Qin li Lu-kai Song School of Energy and Power Engineering Beihang UniversityBeijing100191China Department of Mechanical Engineering The Hong Kong Polytechnic UniversityKowloonHong Kong999077China Research Institute of Aero-Engine Beihang UniversityBeijing100191China

Fatigue reliability-based design optimization of aeroengine structures involves multiple repeated calculations of reliability degree and large-scale calls of implicit high-nonlinearity limit state function,leading to the traditional direct Monte Claro and surrogate methods prone to unacceptable computing efficiency and *** this case,by fusing the random subspace strategy and weight allocation technology into bagging ensemble theory,a random forest(RF)model is presented to enhance the computing efficiency of reliability degree;moreover,by embedding the RF model into multilevel optimization model,an efficient RF-assisted fatigue reliability-based design optimization framework is *** the low-cycle fatigue reliability-based design optimization of aeroengine turbine disc as a case,the effectiveness of the presented framework is *** reliabilitybased design optimization results exhibit that the proposed framework holds high computing accuracy and computing *** current efforts shed a light on the theory/method development of reliability-based design optimization of complex engineering structures.

关键词： Random forest reliability-based design optimization ensemble learning machine learning

Prescribed-time stabilization and inverse optimal control of stochastic high-order nonlinear systems

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Science China(Information Sciences) 2024年第2期67卷 144-156页

作者： Ran liU hui WANG Wuquan li School of Mathematics and Statistics Science Ludong University

This paper investigates the prescribed-time state-feedback stabilization and prescribed-time inverse optimality problems for stochastic high-order nonlinear systems. First, a time-varying controller is designed by developing scaled quartic Lyapunov functions, which can guarantee that the system has a unique strong solution almost surely on the prescribed interval for any system initial conditions and that the states and the control converge to the origin in a mean-square form within the prescribed time. Then, the controller is redesigned to address the problem of prescribed-time inverse optimal mean-square stabilization. Finally,a concrete example is provided to confirm the efficiency of the proposed design schemes.

关键词： stochastic high-order nonlinear systems prescribed-time stabilization the scaled design inverse optimality