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城市紧凑度对城市公共服务设施空间可达性的影响

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兰州大学学报（社会科学版） 2024年第3期52卷 66-79页

作者：江曼琦刘蕖魏新月南开大学经济学院天津300071 南开大学经济行为与政策模拟实验室天津300071 交通运输部科学研究院北京100029

高品质公共服务设施体系的建设是打造宜居城市的基础性工程,可达性已经成为我国基本公共服务供给侧结构性改革的两大目标取向之一。目前我国城市发展中存在城市紧凑程度恶化与公共服务设施空间可达性状况不佳并存的局面,从城市空间形态... 详细信息

高品质公共服务设施体系的建设是打造宜居城市的基础性工程,可达性已经成为我国基本公共服务供给侧结构性改革的两大目标取向之一。目前我国城市发展中存在城市紧凑程度恶化与公共服务设施空间可达性状况不佳并存的局面,从城市空间形态这一重要城市整体特性视角研究城市公共服务设施可达性对于优化城市公共服务设施空间布局具有重要意义。以中国地级及以上城市的三类主要公共服务设施为考察对象,量化测度城市公共服务设施空间可达性,在此基础上实证分析城市紧凑度对城市公共服务设施空间可达性的影响,以及对不同类型设施的异质性影响,并检验公共服务设施规模分布和地方财政自主权对上述影响过程的调节效应。实证结果表明,城市紧凑度对城市公共服务设施可达性的影响呈现“U”型,目前多数城市处于U型曲线的上升阶段,高财政自主权强化了紧凑城市建设对于公共服务设施的挤出效应,而设施规模越分散,城市紧凑度对公共服务设施空间可达性的几何正向影响效果越弱。

关键词：城市紧凑度公共服务设施空间可达性设施规模分布地方财政自主权

Hydroxysafflor Yellow A Promotes HaCaT Cell Proliferation and Migration by Regulating HBEGF/EGFR and PI3K/AKT Pathways and Circ_0084443

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Chinese Journal of Integrative Medicine 2024年第3期30卷 213-221页

作者： ZHANG yue XIAO Yan-wei MA Jing-xin WANG Ao-xue Department of Dermatology the Second Hospital of Dalian Medical UniversityDalianLiaoning Province116021China Department of Cell Biology Dalian Medical UniversityDalianLiaoning Province116044China

Objective:To investigate the effect and possible mechanism of hydroxysafflor yellow A(HSYA) on human immortalized keratinocyte cell proliferation and ***:HaCaT cells were treated with *** proliferation was detected by the cell counting kit-8 assay,and cell migration was measured using wound healing assay and Transwell migration *** mRNA and protein expression levels of heparin-binding epidermal growth factor(EGF)-like growth factor(HBEGF),EGF receptor(EGFR),phosphatidylinositol 3-kinase(PI3K),protein kinase B(AKT),mammalian target of rapamycin(mTOR),and hypoxia-inducible factor-1α(HIF-1α) were detected by quantitative real-time polymerase chain reaction(qRT-PCR) and Western blot,***_0084443-overexpressing HaCaT cells and empty plasmid HaCaT cells were constructed using the lentiviral stable transfection and treated with *** expression of circ_0084443 was detected by ***:HSYA(800 μmol/L) significantly promoted HaCaT cell proliferation and migration(P0.05).Conclusion:HSYA played an accelerative role in HaCaT cell proliferation and migration,which may be attributable to activating HBEGF/EGFR and PI3K/AKT signaling pathways,and had a particular inhibitory effect on the keratinocyte negative

关键词： hydroxysafflor yellow A circ_0084443 heparin-binding epidermal growth factor-like growth factor/epidermal growth factor receptor phosphatidylinositol 3-kinase/protein kinase B

Simulation study of the performance of the Very Large Area gamma-ray Space Telescope

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Nuclear Science and Techniques 2024年第9期35卷 1-17页

作者： Xu Pan wei Jiang Chuan yue Shi-Jun Lei Yu-xin Cui Qiang Yuan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China

The Very Large Area gamma-ray Space Telescope(VLAST)is a mission concept proposed to detect gamma-ray photons through both Compton scattering and electron–positron pair production mechanisms,thus enabling the detection of photons with energies ranging from MeV to *** project aims to conduct a comprehensive survey of the gamma-ray sky from a low-Earth orbit using an anti-coincidence detector,a tracker detector that also serves as a low-energy calorimeter,and a high-energy imaging *** developed a Monte Carlo simulation application of the detector using the GEANT4 toolkit to evaluate the instrument performance,including the effective area,angular resolution,and energy resolution,and explored specific optimizations of the detector *** simulation-based analysis indicates that the current design of the VLAST is physically feasible,with an acceptance above 10 m^(2)sr which is four times larger than that of the Fermi-LAT,an energy resolution better than 2%at 10 GeV,and an angular resolution better than 0.2◦at 10 *** VLAST project promises to make significant contributions to the field of gamma-ray astronomy and enhance our understanding of the cosmos.

关键词： Space astronomy Gamma-ray telescope Calorimeter Monte Carlo simulation

Elite Dung Beetle Optimization Algorithm for Multi-UAV Cooperative Search in Mountainous Environments

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Journal of Bionic Engineering 2024年第4期21卷 1677-1694页

作者： Xiaoyong Zhang wei yue The College of Marine Electrical Engineering Dalian Maritime UniversityDalian116026China

This paper aims to address the problem of multi-UAV cooperative search for multiple targets in a mountainous environment,considering the constraints of UAV dynamics and prior environmental ***,using the target probability distribution map,two strategies of information fusion and information diffusion are employed to solve the problem of environmental information inconsistency caused by different UAVs searching different areas,thereby improving the coordination of UAV ***,the task region is decomposed into several high-value sub-regions by using data clustering *** on this,a hierarchical search strategy is proposed,which allows precise or rough search in different probability areas by adjusting the altitude of the aircraft,thereby improving the search ***,the Elite Dung Beetle Optimization Algorithm(EDBOA)is proposed based on bionics by accurately simulating the social behavior of dung beetles to plan paths that satisfy the UAV dynamics constraints and adapt to the mountainous terrain,where the mountain is considered as an obstacle to be ***,the objective function for path optimization is formulated by considering factors such as coverage within the task region,smoothness of the search path,and path *** effectiveness and superiority of the proposed schemes are verified by the simulation.

关键词： Mountainous environment Multi-UAV cooperative search Environment information consistency Elite dung beetle optimization algorithm(EDBOA) Path planning

An Innovative Coupled Common-Node Discrete Element Method-Smoothed Particle Hydrodynamics Model Developed with LS-DYNA and Its Applications

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China Ocean Engineering 2024年第3期38卷 467-482页

作者： SHEN Zhong-xiang WANG Wen-qing XU Cheng-yue LUO Jia-xin LIU Ren-wei School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China College of Harbor Coastal and Offshore EngineeringHohai UniversityNanjing 210098China

In this study,a common-node DEM-SPH coupling model based on the shared node method is proposed,and a fluid–structure coupling method using the common-node discrete element method-smoothed particle hydrodynamics(DS-SPH)method is developed using LS-DYNA *** DEM and SPH are established on the same node to create common-node DEM-SPH particles,allowing for fluid–structure *** simulations of various scenarios,including water entry of a rigid sphere,dam-break propagation over wet beds,impact on an ice plate floating on water and ice accumulation on offshore structures,are *** interaction between DS particles and SPH fluid and the crack generation mechanism and expansion characteristics of the ice plate under the interaction of structure and fluid are also *** results are compared with available data to verify the proposed coupling ***,the simulation results demonstrated that controlling the cutoff pressure of internal SPH particles could effectively control particle splashing during ice crushing failure.

关键词： common-node DEM-SPH fluid-structure interaction discrete element method smoothed particle hydrodynamics

Association of Meteorological Factors with Labial Adhesions in Children: A 7-year Retrospective Analysis with 9,467 Cases

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Biomedical and Environmental Sciences 2019年第9期32卷 715-718页

作者： ZHAO Tian xin LUO Qing WANG Jun Ke HAN Lin Dong wei yue xin SUN Mang LIU Bin SHEN Lian Ju LONG Chun Lan YU Cheng Jun LIN Tao WU Sheng De wei Guang Hui Department of Urology Children's Hospital of Chongqing Medical University Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering Ministry of Education Key Laboratory of Child Development and Disorders National Clinical Research Center for Child Health and Disorders(Chongqing China International Science and Technology Cooperation Base of Child Development and Critical Disorders Chongqing Key Laboratory of Pediatrics

Labial adhesions (LA)(also called labial agglutination) are defined as partial or complete agglutination of labia minora. The condition commonly occurs in girls during childhood with an estimated prevalence of 0.6%–5%and a peak incidence in the age-group of 13–24 months[1]. Over half of all patients present with symptoms related to urinary outlet obstruction[2].

关键词： urinary obstruction outlet

A low-frequency and broadband wave-insulating vibration isolator based on plate-shaped metastructures

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Applied Mathematics and Mechanics(English Edition) 2024年第7期45卷 1171-1188页

作者： wei wei Feng GUAN xin FANG College of Intelligent Science National University of Defense TechnologyChangsha410073China Naval Research Academy Beijing100161China

A metamaterial vibration isolator,termed as wave-insulating isolator,is proposed,which preserves enough load-bearing capability and offers ultra-low and broad bandgaps for greatly enhanced wave *** consists of plate-shaped metacells,whose symmetric and antisymmetric local resonant modes offer several low and broad mode bandgaps although the complete bandgap remains high and *** bandgap mechanisms,vibration isolation properties,effects of key parameters,and robustness to complex conditions are *** experimentally demonstrated,the wave-insulating isolator can improve the vibration insulation in the ranges of[50 Hz,180 Hz]and[260 Hz,400 Hz]by 15 dB and 25 dB,respectively,in contrast to the conventional isolator with the same first resonant frequency.

关键词： metamaterial and metastructure vibration isolation bandgap wave insulation plate

Intrahepatic portal venous systems in adult patients with cavernous transformation of portal vein: Imaging features and a new classification

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 481-486页

作者： xin Huang Qian Lu yue-wei Zhang Lin Zhang Zhi-Zhong Ren Xiao-wei Yang Ying Liu Rui Tang Hepatopancreatobiliary Center Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijing 102218China

Background: Cavernous transformation of the portal vein(CTPV) due to portal vein obstruction is a rare vascular anomaly defined as the formation of multiple collateral vessels in the hepatic hilum. This study aimed to investigate the imaging features of intrahepatic portal vein in adult patients with CTPV and establish the relationship between the manifestations of intrahepatic portal vein and the progression of CTPV. Methods: We retrospectively analyzed 14 CTPV patients in Beijing Tsinghua Changgung Hospital. All patients underwent both direct portal venography(DPV) and computed tomography angiography(CTA) to reveal the manifestations of the portal venous system. The vessels measured included the left portal vein(LPV), right portal vein(RPV), main portal vein(MPV) and the portal vein bifurcation(PVB). Results: Nine males and 5 females, with a median age of 40.5 years, were included in the study. No significant difference was found in the diameters of the LPV or RPV measured by DPV and CTA. The visualization in terms of LPV, RPV and PVB measured by DPV was higher than that by CTA. There was a significant association between LPV/RPV and PVB/MPV in term of visibility revealed with DPV( P = 0.01), while this association was not observed with CTA. According to the imaging features of the portal vein measured by DPV, CTPV was classified into three categories to facilitate the diagnosis and treatment. Conclusions: DPV was more accurate than CTA for revealing the course of the intrahepatic portal vein in patients with CTPV. The classification of CTPV, that originated from the imaging features of the portal vein revealed by DPV, may provide a new perspective for the diagnosis and treatment of CTPV.

关键词： Cavernous transformation of the portal vein Classification Direct portal venography Intrahepatic portal venous system

Operando measurement of lattice deformation profiles of synchrotron radiation monochromator

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Nuclear Science and Techniques 2024年第7期35卷 8-19页

作者： yue Zhang Zhong-Liang Li Shang-Yu Si Lian Xue Hong-xin Luo Xiao-wei Zhang Jun Hu Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai201204China ShanghaiTech University Shanghai201210China University of the Chinese Academy of Sciences Beijing100049China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of ScienceBeijing100049China

This study presents a new method for characterizing the thermal lattice deformation of a monochromator with high precision under service conditions and first reports the operando measurements of nanoscale thermal lattice deformation on a double-crystal monochromator at different incident *** nanoscale thermal lattice deformation of the monochromator first crystal was obtained by analyzing the intensity of the distorted DuMond *** diagrams of the 333 diffraction index,sensitive to lattice deformation,were obtained directly using a 2D detector and an analyzer crystal orthogonal to the *** increasing incident power and power density,the maximum height of the lattice deformation increased from 3.2 to 18.5 nm,and the deformation coefficient of the maximum height increased from 1.1 to 3.2 nm/*** maximum relative standard deviation was 4.2%,and the maximum standard deviation was 0.1 *** on the measured thermal deformations,the flux saturation phenomenon and critical point for the linear operation of the monochromator were predicted with increasing incident *** study provides a simple solution to the problem of the lower precision of synchrotron radiation monochromator characterizations compared to simulations.

关键词： Synchrotron radiation Monochromator Lattice deformation X-ray dynamic diffraction