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Evolution and Determinants of Population Agglomeration in Less Developed Metropolitan Areas:A Case Study of the Taiyuan Metropolitan Area,China

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Chinese Geographical Science 2024年第4期34卷 739-751页

作者： QIN Zhiqin liang ye AN Shuwei DOU Yongjing School of Economics and Management Shanxi UniversityTaiyuan 030031China School of Urban Economics and Public Affairs Capital University of Economics and BusinessBeijing 100070China School of Geography Science Taiyuan Normal UniversityJinzhong 030619China

It is of importance to enhance the urban areas'capacity for population aggregation in underdeveloped regions,aiming to rectify the imbalanced and insufficient pattern of economic development in *** the Taiyuan Metropolitan Area(TMA)in central China as a case study,this paper examines the evolutionary process and characteristics of population agglomeration from 2000 to 2020,and identifies factors associated with agglomeration and their spatial *** findings indicated that:1)against the background of sustained population shrinkage in the provincial area,the TMA showed a demographic trend of steady increase,albeit with a decelerated growth *** the metropolitan area,urban population size continued to grow rapidly,whereas the rural areas endured sustained *** in city size continued to widen,and the polarization of concentrated population in the core cities kept increasing.2)Agglomerations in both secondary and service industries had significant positive effects on local population agglomeration,with the former effect being *** economic development,government fiscal expenditure,and financial advancement all contributed to facilitating local population *** a spatial spillover perspective,service agglomeration and financial development promoted population agglomeration in surrounding ***,fiscal expenditure inhibited such *** for industrial agglomeration and regional economic development,their spatial spillover effects were *** results obtained reveal several policy implications aimed at enhancing the population agglomeration capacity of the metropolitan area in underdeveloped regions during the new era.

关键词： population agglomeration population shrinkage spatial spillover effects Taiyuan Metropolitan Area(TMA) China

Effect of fatigue load on the bending tribo-corrosion-fatigue behaviors between the main cable wires

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Friction 2024年第7期12卷 1512-1531页

作者： Bo wang Dagang wang Jihong ye liang TANG Hailang CHONG Wei XU Xinxin ZHANG Jianhao CHEN Haiyan DENG Jie ZHANG Guowen YAO Magd Abdel WAHAB School of Mechatronic Engineering China University of Mining and TechnologyXuzhou 221116China Xuzhou Key Laboratory for Fire Safety of Engineering Structures China University of Mining and TechnologyXuzhou 221116China National Wire Rope Quality Inspection Center Nantong Product Quality Supervision and Inspection InstituteNantong 226011China Jiangsu Langshan Wire Rope Co. Ltd.Nantong 226003China School of Mechatronic Engineering Southwest Petroleum UniversityChengdu 610500China School of Civil Engineering Chongqing Jiaotong UniversityChongqing 400074China Soete Laboratory Faculty of Engineering and ArchitectureGhent UniversityZwijnaarde B-9052Belgium

The main cable bent around the saddle of the suspension bridge is subjected to the wind,the vehicle,the bridge’s own weight and the corrosive *** coupling of the three loads and the environments causes the friction,the corrosion,and the fatigue(tribo-corrosion-fatigue)among the wires inside the main *** this paper,a wire bending tribo-corrosion-fatigue test rig was designed and *** effect of fatigue load on the bending friction behaviors between the cable wires in ultrapure water and 3.5%NaCl solution was *** tribological properties and electrochemical corrosion behaviors under different fatigue loading ranges were *** tribo-corrosion-fatigue interaction between the cable wires was quantitatively characterized,and the mechanism of the interaction was *** results demonstrate that the increasing fatigue load exacerbates the coupling damage of the cable wires attributed to the enhanced *** findings carry theoretical importance when assessing the main cable’s deterioration and the load-bearing safety of a suspension bridge.

关键词： bending tribo-corrosion-fatigue interaction parallel steel wires fatigue load

Commentary:Gut microbiota reduce the risk of hyperuricemia and gout in the human body

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Acta Pharmaceutica Sinica B 2024年第1期14卷 433-435页

作者： Lin wang Jianping ye Metabolic Disease Research Center Zhengzhou University Affiliated Zhengzhou Central HospitalZhengzhou 450007China Research Center for Basic Medicine Academy of Medical SciencesZhengzhou UniversityZhengzhou 450052China

Gout,a prevalent and painful metabolic disease often associated with obesity and aging,is caused by the deposition of urate crystals in joints,bones,or soft *** is an intermediate metabolite within the purine degradation pathway,predominantly derived from uric acid under physiological pH *** occurs due to excessive uric acid production or insufficient excretion2,which is associated with various chronic diseases,including type 2 diabetes.

关键词： Uric acid Gout Microbiota Gut Uricase

Underwater Pulse Waveform Recognition Based on Hash Aggregate Discriminant Network

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Journal of Ocean University of China 2024年第3期23卷 654-660页

作者： wang Fangchen ZHONG Guoqiang wang liang College of Computer Science and Technology Ocean University of ChinaQingdao 266100China College of Marine Technology Ocean University of ChinaQingdao 266100China

Underwater pulse waveform recognition is an important method for underwater object *** existing works focus on the application of traditional pattern recognition methods,which ignore the time-and space-varying characteristics in sound propagation channels and cannot easily extract valuable waveform *** propagation channels in seawater are time-and space-varying convolutional *** the extraction of the waveform features of underwater acoustic signals,the effect of high-accuracy underwater acoustic signal recognition is identified by eliminating the influence of time-and space-varying convolutional channels to the greatest extent *** propose a hash aggregate discriminative network(HADN),which combines hash learning and deep learning to minimize the time-and space-varying effects on convolutional channels and adaptively learns effective underwater waveform features to achieve high-accuracy underwater pulse waveform *** the extraction of the hash features of acoustic signals,a discrete constraint between clusters within a hash feature class is *** constraint can ensure that the influence of convolutional channels on hash features is *** addition,we design a new loss function called aggregate discriminative loss(AD-loss).The use of AD-loss and softmax-loss can increase the discriminativeness of the learned hash *** results show that on pool and ocean datasets,which were collected in pools and oceans,respectively,by using acoustic collectors,the proposed HADN performs better than other comparative models in terms of accuracy and mAP.

关键词： convolutional channel hash aggregate discriminative network aggregate discriminant loss waveform recognition

Atomic-Scale Insights into Damage Mechanisms of GGr15 Bearing Steel Under Cyclic Shear Fatigue

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1265-1278页

作者： Qiao-Sheng Xia Dong-Peng Hua Qing Zhou ye-Ran Shi Xiang-Tao Deng Kai-Ju Lu Hai-Feng wang Xiu-Bing liang Zhao-Dong wang State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi’an710072China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819China Defense Innovation Institute Academy of Military ScienceBeijing100071China

Alternating shear stress is a critical factor in the accumulation of damage during rolling contact fatigue,severely limiting the service life of ***,the specific mechanisms responsible for the cyclic shear fatigue damage in bearing steel have not been fully *** the mechanical response and microstructural evolution of a model GGr15 bearing steel under cyclic shear loading are investigated through the implementation of molecular dynamics *** samples undergo 30 cycles under three different loading conditions with strains of 6.2%,9.2%,and 12.2%,*** findings indicate that severe cyclic shear deformation results in early cyclic softening and significant accumulation of plastic damage in the bearing ***,samples subjected to higher strain-controlled loading exhibit higher plastic strain energy and shorter fatigue ***,strain localization is identified as the predominant damage mechanism in cyclic shear fatigue of the bearing steel,which accumulates and ultimately results in fatigue ***,simulation results also revealed the microstructural reasons for the strain localization(e.g.,BCC phase transformation into FCC and HCP phase),which well explained the formation of white etching *** study provides fresh atomic-scale insights into the mechanisms of cyclic shear fatigue damage in bearing steels.

关键词： Cyclic shear fatigue Molecular dynamic simulation Bearing steels Plastic damage accumulation

Thermally modulated photoelectronic synaptic behavior in HfS_(2)/VO_(2) heterostructure

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Rare Metals 2024年第8期43卷 3798-3809页

作者： Le wang Lin wang Xiao-Yun ye Xiong-Hu Xu Li-Yan Shang Ya-Wei Li Jin-Zhong Zhang liang-Qing Zhu Zhi-Gao Hu Technical Center for Multifunctional Magneto-Optical Spectroscopy(Shanghai) Engineering Research Center of Nanophotonics&Advanced Instrument(Ministry of Education)Department of PhysicsSchool of Physics and Electronic ScienceEast China Normal UniversityShanghai 200241China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

Neuromorphic computing is known for its efficient computational speed,low latency,and reduced power consumption,which is considered a pivotal technology to overcome the von Neumann *** synapses are an indispensable component of neuromorphic computational artificial neural *** guarantee effective and precise processing of optical signals,it must have a high responsivity,detectivity,and the ability to adapt to various ***,a synaptic transistor based on the HfS_(2)/VO_(2) heterojunction with a responsivity of8.6×10^(3) A·W^(-1)and a detectivity of 1.26×10^(14)Jones at405 nm laser was ***,the typical synaptic behavior was successfully simulated,including postsynaptic currents(PSCs),the transition from shortterm plasticity(STP)to long-term plasticity(LTP).When VO_(2) converts from the semiconductor state to the metal state,the HfS_(2)/VO_(2) heterojunction transforms into a Schottky heterojunction from a TypeⅡheterojunction with ***'s important,the heterojunction still exhibits excellent responsivity and detectivity,as well as stability of synaptic *** addition,the classical Pavlovian conditioning experiment is simulated under different laser intensity to study the brain's associative learning *** results demonstrate that the HfS_(2)/VO_(2) heterojunction synapse exhibits significant responsivity and detectivity and is adaptable to high-temperature environments,showing great potential for neuromorphic computational applic ations.

关键词： HfS_(2) VO_(2) Phase transition Photoelectric synapse Heterojunction

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Digital signal acquisition system for complex nuclear reaction experiments

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Nuclear Science and Techniques 2024年第1期35卷 124-133页

作者： Wei-liang Pu Yan-Lin ye Jian-Ling Lou Jia-Hao Chen School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871China Institute of Applied Physics and Computational Mathematics Beijing 100094China

A digital data-acquisition system based on XIA LLC products was used in a complex nuclear reaction experiment using radioactive ion beams.A flexible trigger system based on a field-programmable gate array(FPGA)parametrization was developed to adapt to different experimental sizes.A user-friendly interface was implemented,which allows converting script language expressions into FPGA internal control *** proposed digital system can be combined with a conventional analog data acquisition system to provide more *** performance of the combined system was veri-fied using experimental data.

关键词： Digital signal acquisition system Trigger Programmable logic Timestamp

Drosophila adhesion GPCR Remoulade regulates axon growth, branching, and guidance by modulating Rac1 GTPase

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Journal of Genetics and Genomics 2024年第4期51卷 458-461页

作者： Xi Yang Changkun Pan Meitong ye Jinshuo liang Haoyang Cheng Qing liang Shu Huang Jianshu wang Hoi yee Chow Haihuai He Cancer Center and State Key Laboratory of Biotherapy West China HospitalSichuan UniversityChengduSichuan 610041China National Clinical Research Center for Geriatrics and State Key Laboratory of Biotherapy West China HospitalSichuan UniversityChengduSichuan 610041China Department of Neurosurgery Cancer Center and State Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengduSichuan 610041China

The assembly of neurons into complex circuits relies upon appropriate axonal navigation to distant *** considerable progress has been made toward understanding the regulation of the guidance and branching of axon extension,the molecular and cellular mechanisms underlying the coordination of the motility of the axon tip,axon growth,and branching remain largely unknown(Sudhof,2017).The Drosophila mushroom body(MB),the major site for associative learning and memory,is a powerful model system to investigate complex axon *** MB is a bilaterally symmetric central brain structure,mainly composed of Kenyon cells,MB output neurons,and dopaminergic neurons(Li et al.,2020).Among the seven neuronal subtypes of~2000 Kenyon cells,Y,a/β,and a/β'subtypes extend axons in a fascicle and bifurcate to produce two sister branches,one projecting into the dorsal lobe and the other into the medial lobe.

关键词： branching medial axon

Geometrical transition properties of vortex cavitation and associated flow-choking characteristics in poppet valves

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第6期25卷 455-469页

作者： liang LU Zhongdong liang Yuming LIU Zhipeng wang Shohei RYU School of Mechanical Engineering Tongji UniversityShanghai 201804China Frontiers Science Center for Intelligent Autonomous Systems Tongji UniversityShanghai 201210China Technical Research Laboratory Hitachi Construction Machinery Co.Ltd.Tsuchiura 300-0013Japan

Poppet valves have become increasingly significant in ensuring precise digital flow rate and pressure control in hydraulic systems,necessitating a more profound understanding of the geometrical properties of cavitation in them,as well as associated flow-choking *** a comparative analysis with experimentally observed cavity images,we found that large eddy simulation(LES)turbulence modeling effectively replicates the geometrical properties of cavitation in these *** analysis demonstrated that cavitation is generated from vortices that result from the interaction between the notch contracta flow and the surrounding fluid *** in the internal or external vena contracta conditions result in fixed or discrete cavities,and the length-to-diameter ratio serves as a measure of the transition between internal and external vena contracta flow *** study establishes a threshold length-to-diameter ratio of approximately 2 for the tested poppet *** specifically,in notch structures with a smaller valve opening,longer sealing length,and smaller throttling angle(corresponding to a larger length-to-diameter ratio),the liquid-to-vapor transfer process is more evident than that in the reverse direction.A long-standing vapor cavity becomes fixed inside the notch,leading to a more pronounced flow-choking *** contrast,for structures with a smaller length-to-diameter ratio,the cavitation process for discrete vapor cavities is more complete,ensuring fluid flow continuity and significantly reducing the occurrence of the flow-choking phenomenon.

关键词： Poppet valves Vena contracta Vortex flow Vapor cavity Flow-choking