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The Bright Single Pulse Emission from PSR B1133+16

Research in Astronomy and Astrophysics 2024年第4期24卷 253-261页

作者： Jun Tan Zhi-Gang Wen Zhen Wang Xue-Feng Duan Hong-Guang Wang Na Wang Vishal Gajjar Jian-Ping Yuan Rai Yuen Wen-Ming Yan Jian-Ling Chen Wei Han Hui Wang cheng-bing lyu Ai-Jun Dong Maths and Information Technology School Yuncheng UniversityYuncheng 044000China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Xinjiang Key Laboratory of Radio Astrophysics Urumqi 830011China School of Physics and Materials Science Guangzhou UniversityGuangzhou 510006China Space Science Laboratory University of CaliforniaBerkeley 94710USA Department of Physics and Electronic Engineering Yuncheng UniversityYuncheng 044000China School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550025China

We have conducted a comprehensive investigation into the bright single pulse emission from PSR B1133+16using the Giant Metrewave Radio *** time resolution data(61μs)were obtained at a center frequency of 322 MHz with a bandwidth of 32 MHz over a continuous observation period of 7.45 hr.A total of 1082 bright pulses were sporadically detected with peak flux densities ranging from 10 to 23 times stronger than the average pulse ***,no giant pulse-like emission with a relative pulse energy larger than 10 and extremely short duration was detected,indicating that these bright pulses cannot be categorized as giant pulse *** majority of these bright pulses are concentrated in pulse phases at both the leading and trailing windows of the average pulse profile,with an occurrence ratio of approximately *** pulse energy distribution for all individual pulses can be described by a combination of two Gaussian components and a cutoff power-law with an index of α=-*** updated nulling fraction of 15.35%±0.45% was determined from the energy *** emission of individual pulses follows a log-normal distribution in peak flux density *** is imperative that regular phase drifting in bright pulse sequence is identified in both the leading and trailing components for the first *** physical mechanisms are discussed in detail to provide insights into these observations.

关键词： (stars:)pulsars:general (stars:)pulsars:individual(PSR B1133+16) methods:observational methods:data analysis

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Investigation of the active ingredients and mechanism of Shuangling extract in dextran sulfate sodium salt induced ulcerative colitis mice based on network pharmacology and experimental verification

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Journal of Traditional Chinese Medicine 2024年第3期44卷 478-488页

作者： CHU Mengzhen WANG Yu LIN Zhijian lyu Jintao ZHANG Xiaomeng ZHANG bing Department of Clinical Chinese Pharmacy School of Chinese Materia MedicaBeijing University of Chinese MedicineBeijing 102488China

OBJECTIVE: To explore the pharmacodynamic effects and potential mechanisms of Shuangling extract against ulcerative colitis(UC). METHODS: The bioinformatics method was used to predict the active ingredients and action targets of Shuangling extract against UC in mice. And the biological experiments such as serum biochemical indexes and histopathological staining were used to verify the pharmacological effect and mechanism of Shuangling extract against UC in mice. RESULTS: The Shuangling extract reduced the levels of seruminterleukin-1β(IL-1β), tumor necrosis factor-α(TNF-N), interleukin-6(IL-6) and other inflammatory factors in UC mice and inhibited the inflammatory response. AKT Serine/threonine Kinase 1 and IL-6 may be the main targets of the anti-UC action of Shuangling extract, and the TNF signaling pathway, Forkhead box O signaling pathway and T-cell receptor signaling pathway may be the main signaling pathways. CONCLUSION: The Shuangling extract could inhibit the inflammatory response induced by UC and regulate intestinal immune function through multiple targets and multiple channels, which provided a new option and theoretical basis for anti-UC.

关键词： colitis ulcerative pharmacodynamic study network pharmacology molecular docking simulation Shuangling extract

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Printable,flexible ceramic fiber paper based on electrospinning

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Rare Metals 2024年第6期43卷 2739-2746页

作者： Yong-Shuai Xie Yuan cheng Yang lyu Rui Li Jie-Cai Han National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of TechnologyHarbin 150001China State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China

Based on the fact that it is challenging for the polymer flexible circuit substrates to meet the requirements of serving in high-temperature environments,this work proposed the idea of using printable ceramic fiber paper as a high-temperature flexible circuit substrate.A ceramic fiber paper with all ceramic components had been developed via electrospinning,solving the problems of low strength and severe strength drop at high temperatures of traditional ceramic fiber *** tensile strength of the prepared ceramic fiber paper is 2.63 MPa,and the reliable service temperature is 1200℃.Its bulk density is about 1.5 times that of traditional ceramic fiber *** can be printed with patterns by commercial inkjet printers like ordinary printing paper and has excellent *** feasibility of ceramic fiber paper as a flexible circuit substrate was verified by constructing a simple *** the fiber paper is significantly bent,the circuit still forms a complete path,which proves that it has a strong application potential for high-temperature flexible circuit substrate and is expected to promote the development of flexible electronic devices serving at extreme high-temperature environments.

关键词： Ceramic fiber paper High temperature Inkjet printing Flexible electronic

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Energy Stable Nodal DG Methods for Maxwell’s Equations of Mixed-Order Form in Nonlinear Optical Media

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Communications on Applied Mathematics and Computation 2024年第1期6卷 30-63页

作者： Maohui lyu Vrushali A.Bokil Yingda cheng Fengyan Li State Key Laboratory of Scientific and Engineering Computing(LSEC) Academy of Mathematics and System SciencesChinese Academy of SciencesBeijing100190China Department of Mathematics College of ScienceOregon State UniversityCorvallisOR97331USA Department of Mathematics Michigan State UniversityEast LansingMI48824USA Department of Computational Mathematics Science and EngineeringMichigan State UniversityEast LansingMI48824USA Department of Mathematical Sciences Rensselaer Polytechnic InstituteTroyNY12180USA

In this work,we develop energy stable numerical methods to simulate electromagnetic waves propagating in optical media where the media responses include the linear Lorentz dispersion,the instantaneous nonlinear cubic Kerr response,and the nonlinear delayed Raman molecular vibrational *** the first-order PDE-ODE governing equations considered previously in Bokil et al.(J Comput Phys 350:420–452,2017)and lyu et al.(J Sci Comput 89:1–42,2021),a model of mixed-order form is adopted here that consists of the first-order PDE part for Maxwell’s equations coupled with the second-order ODE part(i.e.,the auxiliary differential equations)modeling the linear and nonlinear dispersion in the *** main contribution is a new numerical strategy to treat the Kerr and Raman nonlinearities to achieve provable energy stability property within a second-order temporal discretization.A nodal discontinuous Galerkin(DG)method is further applied in space for efficiently handling nonlinear terms at the algebraic level,while preserving the energy stability and achieving high-order *** with d_(E)as the number of the components of the electric field,only a d_(E)×d_(E)nonlinear algebraic system needs to be solved at each interpolation node,and more importantly,all these small nonlinear systems are completely decoupled over one time step,rendering very high parallel *** evaluate the proposed schemes by comparing them with the methods in Bokil et al.(2017)and lyu et al.(2021)(implemented in nodal form)regarding the accuracy,computational efficiency,and energy stability,by a parallel scalability study,and also through the simulations of the soliton-like wave propagation in one dimension,as well as the spatial-soliton propagation and two-beam interactions modeled by the two-dimensional transverse electric(TE)mode of the equations.

关键词： Maxwell’s equations Kerr and Raman Discontinuous Galerkin method Energy stability

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Compliance motion control of the hydraulic dual-arm manipulator with adaptive mass estimation of unknown object

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Frontiers of Mechanical Engineering 2024年第1期19卷 35-52页

作者： Bolin SUN Min cheng Ruqi DING bing XU State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing 400044China Key Laboratory of Conveyance and Equipment(Ministry of Education) East China Jiaotong UniversityNanchang 330013China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China

Given the limited operating ability of a single robotic arm,dual-arm collaborative operations have become increasingly *** with the electrically driven dual-arm manipulator,due to the unknown heavy load,difficulty in measuring contact forces,and control complexity during the closed-chain object transportation task,the hydraulic dual-arm manipulator(HDM)faces more difficulty in accurately tracking the desired motion trajectory,which may cause object deformation or even *** overcome this problem,a compliance motion control method is proposed in this paper for the *** mass parameter of the unknown object is obtained by using an adaptive method based on velocity *** to the difficulty in obtaining the actual internal force of the object,the pressure signal from the pressure sensor of the hydraulic system is used to estimate the contact force at the end-effector(EE)of two hydraulic manipulators(HMs).Further,the estimated contact force is used to calculate the actual internal force on the ***,a compliance motion controller is designed for HDM closed-chain *** position and internal force errors of the object are reduced by the feedback of the position,velocity,and internal force errors of the object to achieve the effect of the compliance motion of the HDM,i.e.,to reduce the motion error and internal force of the *** required velocity and force at the EE of the two HMs,including the position and internal force errors of the object,are inputted into separate position *** addition,the position controllers of the two individual HMs are designed to enable precise motion control by using the virtual decomposition control ***,comparative experiments are carried out on a hydraulic dual-arm test *** proposed method is validated by the experimental results,which demonstrate improved object position accuracy and reduced internal force.

关键词： hydraulic dual-arm manipulator compliance motion control unknown object adaptive mass estimation nonlinear control

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Exposure to Chloropropanols and Their Fatty Acid Esters and Glycidyl Fatty Acid Esters in the Sixth Total Diet Study—China,2016-2019

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China CDC weekly 2024年第24期6卷 563-567,I0001页

作者： Dan Huang Xiaomin Xu bing lyu Jingguang Li Yunfeng Zhao Yongning Wu School of Population Medicine and Public Health Chinese Academy of Medical Sciences Peking Union Medical CollegeBeijingChina NHC Key Lab of Food Safety Risk Assessment Research Unit of Food SafetyChina National Center for Food Safety Risk AssessmentBeijingChina Zhejiang Provincial Center for Disease Control and Prevention Hangzhou CityZhejiang ProvinceChina

What is already known about this topic?Chloropropanols,along with their fatty acid esters and glycidyl fatty acid esters(GEs),are prevalent contaminants in a variety of processed foods,posing potential health risks to *** is added by this report?In the Sixth China Total Diet Study(TDS),3-monochloropropane-1,2-diol esters(3-MCPD esters)and GEs were identified as the predominant chloropropanols and their esters in composite food ***(47.0%)and cereals(15.4%)were the major contributors to exposure among the 12 food categories *** are the implications for public health practice?The Sixth China TDS highlighted concerns regarding potential health risks associated with dietary exposure to *** study underscores the need for further attention in devising practical strategies to mitigate dietary exposure to GEs.

关键词： esters predominant 1,2

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Time-dependent behavior and permeability evolution of limestone under hydro-mechanical coupling

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Journal of Mountain Science 2024年第5期21卷 1697-1714页

作者： WANG Zhilong ZENG Zhengqiang lyu cheng WANG Mingnian HU Xiongyu DONG Yucang School of Civil Engineering Southwest Jiaotong UniversityChengdu 61003China College of Civil Engineering Tongji UniversityShanghai 200092China College of Water Resource and Hydropower Sichuan UniversityChengdu 610065China Hebei GEO University Shijiazhuang 050031China

Excessively high pore water pressure presents unpredictable risks to the safety of rock tunnels in mountainous regions that are predominantly composed of limestone. Investigating the creep characteristics and permeability evolution of limestone under varying hydrated conditions is crucial for a better understanding of the delayed deformation mechanisms of limestone rock tunnels. To this end, this paper initially conducts a series of multi-stage triaxial creep tests on limestone samples under varying pore water pressures. The experiment examines how pore water pressure affects limestone’s creep strain, strain rate, long-term strength, lifespan, and permeability, all within the context of hydraulicmechanical(HM) coupling. To better describe the creep behavior associated with pore water pressure, this paper proposes a new nonlinear fractional creep constitutive model. This constitutive model depicts the initial, steady-state, and accelerated phases of limestone’s creep behavior. Finally, the proposed model is applied to the numerical realization of deformation in limestone tunnel, validating the effectiveness of the proposed constitutive model in predicting tunnel’s creep deformation. This research enhances our understanding of limestone’s creep characteristics and permeability evolution under HM coupling, laying a foundation for assessing the longterm stability of mountain tunnels.

关键词： Creep test Hydraulic-mechanical coupling Creep constitutive model Fractional derivatives Pore pressure

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Differential Operator Approach to■quantum Groups and Their Oscillator Representations

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1360-1374页

作者： Zhao bing FAN Ji cheng GENG Shao Long HAN College of Mathematical Science Harbin Engineering UniversityHarbin 150001P.R.China

For a quasi-split Satake diagram,we define a modified q-Weyl algebra,and show that there is an algebra homomorphism between it and the corresponding■quantum *** other words,we provide a differential operator approach to■quantum ***,the oscillator representations of■quantum groups are *** crystal basis of the irreducible subrepresentations of these oscillator representations are constructed.

关键词： ■quantum group differential operator oscillator representation crystal basis

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Simplified liver imaging reporting and data system for the diagnosis of hepatocellular carcinoma on gadoxetic acid-enhanced magnetic resonance imaging

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2439-2448页

作者： Rong lyu Wei-Juan Hu Di Wang Jiao Wang Yu-bing Ye Ke-Feng Jia Department of Radiology Tianjin Third Central HospitalTianjin Key Laboratory of Extracorporeal Life Support for Critical DiseasesArtificial Cell Engineering Technology Research CenterTianjin 300170China

BACKGROUND The liver imaging reporting and data system(LI-RADS)diagnostic table has 15 cells and is too *** diagnostic performance of LI-RADS for hepatocellular carcinoma(HCC)is not satisfactory on gadoxetic acid-enhanced magnetic resonance imaging(EOB-MRI).AIM To evaluate the ability of the simplified LI-RADS(sLI-RADS)to diagnose HCC on *** A total of 331 patients with 356 hepatic observations were retrospectively *** diagnostic performance of sLI-RADS A-D using a single threshold was evaluated and compared with LI-RADS v2018 to determine the optimal *** algorithms of sLI-RADS A-D are as follows:The single threshold for sLI-RADS A and B was 10 mm,that is,classified observations≥10mm using an algorithm of 10-19 mm observations(sLI-RADS A)and≥20 mm observations(sLI-RADS B)in the diagnosis table of LI-RADS v2018,respectively,while the classification algorithm remained unchanged for observations0.999).With HBP hypointensity as an MF,the sensitivity of F-sLI-RADS was greater than that of LI-RADS v2018(93.0%vs 87.0%,P<0.001)and sLI-RADS D(93.0%vs 89.8%,P=0.016),without a lower specificity(86.5%vs 90.1%,P=0.062;86.5%vs 89.4%,P=0.125).Compared with that of LI-RADS v2018,the time to classif

关键词： Hepatocellular carcinoma Magnetic resonance imaging Liver Diagnosis Contrast agent

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Investigating the dynamics and interactions of surface features on Pine Island Glacier using remote sensing and deep learning

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Advances in Climate Change Research 2024年第4期15卷 609-622页

作者： Qi ZHU Hua-Dong GUO Lu ZHANG Dong LIANG Zhe-Rong WU Zhuo-Ran lyu Xiao-bing DU Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100094China International Research Center of Big Data for Sustainable Development Goals Beijing 100094China University of Chinese Academy of Sciences Beijing 100049China School of Integrative Plant Science Soil and Crop Sciences SectionCornell University Ithaca 14850USA

Pine Island Glacier(PIG),the largest glacier in the Amundsen Sea Embayment of West Antarctica,has contributed to over a quarter of the observed sea level rise around *** recent years,multiple observations have confirmed its continuous retreat,ice flow acceleration and profound surface *** these changes is crucial for accurately monitoring ice mass discharge and future Antarctic contributions to sea level ***,it is essential to investigate the complex interactions between these variables to comprehend how they collectively affect the overall stability of the intricate PIG *** this study,we utilized high-resolution remote sensing data and deep learning method to detect and analyze the spatio-temporal variations of surface melt,ice shelf calving,and ice flow velocity of the PIG from 2015 to *** explored the correlations among these factors to understand their long-term impacts on the glacier's *** findings reveal a retreat of 26.3 km and a mass loss of 1001.6 km²during ***,extensive surface melting was observed,particularly in the 2016/2017 and 2019/2020 melting *** data vividly illustrate prolonged and intense melting periods,correlating with a significant retreat in the glacier's terminus position in 2019/***,the comprehensive analysis of surface melting and the cumulative retreat of the ice shelf from 2017 to 2020 on the PIG shows atemporal relationship with subsequent significant changes in ice fow velocity,ranging from 10.9 to 12.2 m d^(-1),with an average acceleration rate of 12%.These empirical findings elucidate the intricate relationship among surface melt,ice flow velocity,and consequential glacier dynamics.A profound understanding of these interrelationships holds paramount importance in glacier dynamic changes and modeling,providing invaluable insights into potential glacier responses to global climate change.

关键词： Pine island glacier Calving front Surface melt Ice flow velocity Remote sensing

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