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Property(ω) and Its Perturbations

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Acta Mathematica Sinica,English Series 2014年第5期30卷 797-804页

作者： wei Juan shi Xiao Hong cao College of Mathematics and Information Science Shaanxi Normal University

Abstract A Hilbert space operator T is said to have property （ω1） if σα（T）／σaw（T） π00（T）, where σα（T） andσαw（T） denote the approximate point spectrum and the Weyl essential approximate point spectrum of T respectively, and π00（T） ---- {λ∈ iso σ（T）, 0 〈 dim N（T- λI）〈 ∞}. Ifσα（T）／σαw（T） = π00（T）, we say T satisfies property （w）. In this note, we investigate the stability of the property （wi） and the property （w） under compact perturbations, and we characterize those operators for which the property （wi） and the property （w） are stable under compact perturbations.

关键词： Property (ω1) property (ω) compact perturbations

基于格网尺度的黄河中游地区经济城镇化与PM_(2.5)浓度的脱钩关系研究

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生态经济 2025年第1期41卷 132-139页

作者：沈威曹威威洛阳师范学院地理与旅游学院河南洛阳471022 河南大学地理与环境学院河南开封475004

针对当前经济城镇化参量公里网格数据的缺乏,以黄河中游地区为例,提出一种利用1995—2018年高精度土地利用栅格数据和统计年鉴数据的经济城镇化参量空间化模拟方法,并分析格网尺度下黄河中游地区经济城镇化与PM2.5浓度的脱钩关系演变。... 详细信息

针对当前经济城镇化参量公里网格数据的缺乏,以黄河中游地区为例,提出一种利用1995—2018年高精度土地利用栅格数据和统计年鉴数据的经济城镇化参量空间化模拟方法,并分析格网尺度下黄河中游地区经济城镇化与PM2.5浓度的脱钩关系演变。结果表明:(1)黄河中游地区经济城镇化水平呈现出以兰西城市群、西安城市圈、太原城市圈、郑州—洛阳城市带为核心的多核心圈层结构。(2)在空间格局演变上,不同区域经济城镇化的扩张模式存在差异。受地形限制和水文条件限制,洛河流域、汾河流域、关中平原、太原城市圈经济城镇化呈现以中心城市为核心的带状扩张特征;兰西城市群、郑州—洛阳城市带、呼和浩特市呈现以中心城市为核心的圈层式扩张特征。(3)2005年之后,黄河中游中东部地区开始出现脱钩转折点;2010年之后,黄河中游西部地区开始出现脱钩转折点,但由于西部大开发战略的实施,导致2015—2018年甘肃和宁夏南部扩张负脱钩区面积显著增加,经济城镇化与环境污染的脱钩关系再次发生转变。

关键词：经济城镇化土地利用回归模型 PM2.5浓度脱钩状态

Unraveling post-growth mechanisms of monolayer CsPbBr3 nanocubes:Laser-enhanced transformations and cathodoluminescence-electron microscopy correlations

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Journal of Energy Chemistry 2025年第1期100卷 146-156页

作者： Mingxing Li Xiaoge Wang Xiaofan cao Zhiqun He Chunjun Liang Mingxing Chen Jing Ju Fangtian You Key Laboratory of Luminescence and Optical Information Ministry of Education Institute of Optoelectronic Technology Beijing Jiaotong University Beijing National Laboratory for Molecular Sciences (BNLMS) College of Chemistry and Molecular Engineering Peking University

Lead-halide perovskite nanoparticles（LHP NPs） are highly promising materials for next-generation displays and solid-state lighting due to their exceptional optical properties. However, their inherent instability presents a significant challenge. Recent advances have demonstrated that optoelectronic devices based on monolayer nanoparticle films exhibit both high luminescence efficiency and long-term *** research demonstrates that mobility limitations and anisotropic alignments in CsPbBr3nanocube monolayer films are key to their stabilization, hindering spontaneous growth through face-to-face fusion and resulting in the formation of connecting necks in a diagonal direction. Introducing laser irradiation confirmed this by significantly accelerating nanocubes growth, increasing mobility, and enhancing local structural ordering, leading to larger and more regularly shaped nanosheets. Fourier transform infrared spectroscopy and energy dispersive spectroscopy line-scan analyses indicated that laser irradiation did not disrupt the ligand structure. Transmission electron microscopy and correlative cathodoluminescence electron microscopy revealed the effects of post-growth and heterogeneous structures, including enhanced luminescence and inhomogeneous intensity in the nanosheets. These findings deepen the understanding of the post-growth mechanism of monolayer nanoparticles and the structure-emission correlation and highlight the unique role of laser irradiation in directing the formation of well-defined and regular nanostructures.

关键词： Post-growth mechanism Heterogeneous structure Single-particle spectroscopy Laser irradiation

Mitophagy in acute central nervous system injuries:regulatory mechanisms and therapeutic potentials

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Neural Regeneration Research 2025年第9期20卷 2437-2453页

作者： Siyi Xu Junqiu Jia Rui Mao Xiang cao Yun Xu Department of Neurology Nanjing Drum Tower HospitalClinical College of Jiangsu UniversityNanjingJiangsu ProvinceChina Department of Neurology Nanjing Drum Tower HospitalChinese Academy of Medical Science&Peking Union Medical CollegeNanjingJiangsu ProvinceChina Department of Neurology Nanjing Drum Tower HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjingJiangsu ProvinceChina State Key Laboratory of Pharmaceutical Biotechnology and Institute of Translational Medicine for Brain Critical Diseases Nanjing UniversityNanjingJiangsu ProvinceChina Jiangsu Key Laboratory for Molecular Medicine Medical School of Nanjing UniversityNanjingJiangsu ProvinceChina Nanjing Neurology Medical Center NanjingJiangsu ProvinceChina

Acute central nervous system injuries,including ischemic stro ke,intracerebral hemorrhage,subarachnoid hemorrhage,traumatic brain injury,and spinal co rd injury,are a major global health *** optimal therapies and improving the long-term neurological functions of patients with acute central nervous system injuries are urgent *** are susceptible to damage after acute central nervous system injury,and this leads to the release of toxic levels of reactive oxygen species,which induce cell ***,a selective form of autophagy,is crucial in eliminating redundant or damaged mitochondria during these *** evidence has highlighted the significant role of mitophagy in acute central nervous system *** this review,we provide a comprehensive overview of the process,classification,and related mechanisms of *** also highlight the recent developments in research into the role of mitophagy in various acute central nervous system injuries and drug therapies that regulate *** the final section of this review,we emphasize the potential for treating these disorders by focusing on mitophagy and suggest future research paths in this area.

关键词： autophagy intracerebral hemorrhage ischemic stroke mitochondria mitochondrial biogenesis mitochondrial quality control mitophagy spinal cord injury subarachnoid hemorrhage traumatic brain injury

Analysis of working behavior of Jinping-I Arch Dam during initial impoundment

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Water Science and Engineering 2016年第3期9卷 240-248页

作者： shi-yong Wu wei cao Jiang Zheng Yalong River Hydropower Development Company Ltd.

To study the stress, deformation, and seepage pressure during the initial impoundment of the Jinping-I Arch Dam, monitoring analysis and numerical calculation were used in a dam behavior analysis that focused on the working behavior of the dam during the late period of the initial impoundment up to the end of November 2014. The numerical calculation was performed based on feedback analysis of the deformation and stress of the arch dam through inversion of the elastic moduli(E) of the dam body and foundation, using a three-dimensional finite element model for the linear elastic material of the arch dam. The main monitoring indices presented insignificant changes in the late period of the initial impoundment, and the results of feedback analysis were consistent with monitoring results. Analysis results also show that the deformations of the dam body and dam foundation were within the design range; the dam stress distributions were normal, with values lower than the design control criteria; and the seepage flows through the dam body and dam foundation were lower than the design drainage capacity of the deep-well pump house, demonstrating that the Jinping-I Arch Dam was in good working condition, and the initial impoundment had been successfully completed. The results of the working behavior analysis of the Jinping-I hydropower project during the initial impoundment can provide references for safe operation of similar projects.

关键词： Dam safety monitoring Working behavior Elastic modulus Dam impoundment Jinping-I hydropower project

复杂主动脉疾病中分支与开窗型腔内支架的创新进展与应用

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中华外科杂志 2025年第1期63卷 45-50页

作者：曹龙葛阳阳郭伟解放军总医院第一医学中心血管外科北京

近年来, 主动脉腔内修复技术治疗累及重要分支的复杂主动脉疾病(如主动脉弓和复杂腹主动脉瘤等), 取得了明显进展。分支、开窗型支架的快速发展, 为无法耐受开放手术的复杂主动脉疾病患者, 提供了安全、有效的微创治疗选择。初步临床证... 详细信息

近年来, 主动脉腔内修复技术治疗累及重要分支的复杂主动脉疾病(如主动脉弓和复杂腹主动脉瘤等), 取得了明显进展。分支、开窗型支架的快速发展, 为无法耐受开放手术的复杂主动脉疾病患者, 提供了安全、有效的微创治疗选择。初步临床证据表明, 分支、开窗型支架的技术成功率和手术效果均较好, 逐渐成为复杂主动脉疾病腔内修复技术创新与发展的重要方向。但不可否认, 分支、开窗型支架在复杂主动脉疾病的腔内治疗中尚处于早期经验积累阶段, 未来还需要一系列高质量研究验证其治疗效果, 并完善其与开放手术及不同腔内技术间的疗效比较。

关键词：主动脉疾病主动脉瘤主动脉弓分支与开窗型腔内支架

CPSO-XGBoost segmented regression model for asphalt pavement deflection basin area prediction

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Science China(Technological Sciences) 2022年第7期65卷 1470-1481页

作者： LI ZhuoXuan shi XinLi cao JinDe WANG XuDong HUANG wei School of Mathematics Southeast UniversityNanjing 210096China School of Cyber Science&Engineering Southeast UniversityNanjing 210096China Yonsei Frontier Lab Yonsei UniversitySeoul 120-749Korea Research Institute of Highway Ministry of TransportBeijing 100088China Intelligent Transportation System Research Center Southeast UniversityNanjing 210096China

The use of non-destructive testing(NDT) equipment, such as the falling weight deflectometer(FWD), provides important estimates of road health and helps to optimize road management regimes. However, periodic road testing and post-processing of the collected data are cumbersome and require much expertise, a considerable amount of time, money, and other resources. This study attempts to develop a reliable prediction method for estimating the deflection basin area of different asphalt pavements using road temperature, load time, and load pressure as main characteristics. The data are obtained from 19 kinds of asphalt pavements on a 2.038-km-long full-scale fleld accelerated pavement testing track named RIOHTrack(Research Institute of Highway Track) in Tongzhou, Beijing. In addition, a chaotic particle swarm algorithm(CPSO) and a segmented regression strategy are proposed in this paper to optimize the XGBoost model. The experiment results of the proposed method are compared with those of classical machine learning algorithms and achieve an average of mean square error and mean absolute error respectively by 5.80 and *** experiments demonstrate the superiority of the XGBoost algorithm over classical machine learning methods in dealing with nonlinear problems in road engineering. Signiflcantly, the method can reduce the frequency of deflection tests without affecting its estimation accuracy, which is a promising alternative way to facilitate the rapid assessment of pavement conditions.

关键词： FWD pavement management systems RIOHTrack deflection basin area CPSO XGBoost segmented regression model

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Complex network approach for the evaluation of asphalt pavement design and construction: a longitudinal study

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Science China(Information Sciences) 2022年第7期65卷 210-224页

作者： Hanjie LIU Jinde cao wei HUANG Xinli shi Xudong WANG School of Mathematics Southeast University Jiangsu Provincial Key Laboratory of Networked Collective Intelligence Southeast University Research Institute of Highway Ministry of Transport Intelligent Transportation System Research Center Southeast University School of Cyber Science and Engineering Southeast University

The assessment of asphalt pavement structures with diversified designs and constructions has been a critical challenge due to the practical limitations in testing and methodology. Here, we propose a complex network approach to the evaluation of longitudinal asphalt pavement performances in the Research Institute of Highway Ministry of Transport track(RIOHTrack). We add to the growing field in which network approaches are employed and indicate the profound application in understanding pavement ***, similar and disparate pavement performances are revealed regardless of their predefined design and construction categories. Evidence shows that short-term pavement performance depends on the strength of the subbase structure, whereas long-term performance relies on the thickness of the asphalt layer. In addition, our results indicate that recycling materials could be an important substitute for reducing the thickness of asphalt concrete and maintaining a healthy service life.

关键词： complex network asphalt pavement structure evaluation longitudinal RIOHTrack

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Extremely Anisotropic Thermoelectric Properties of SnSe Under Pressure

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Energy & Environmental Materials 2023年第3期6卷 58-65页

作者： wei cao Ziyu Wang Ling Miao Jing shi Rui Xiong Key Laboratory of Artificial Micro-and Nano-structures of Ministry of Education School of Physics and TechnologyWuhan UniversityWuhan 430072China The Institute of Technological Sciences Wuhan UniversityWuhan 430072China Suzhou Institute of Wuhan University Suzhou 215123China School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China

SnSe has attracted extensive attention due to its ultralow thermal conductivity and excellent thermoelectric *** this work,pressure-induced thermoelectric properties of Pnma SnSe are investigated via first-principles *** uncover distinct energy isosurfaces topology transition of conduction band by applying *** newly created conduction band valley caused by pressure has a distinct anisotropic shape compared to the old *** pressure can greatly enhance the anisotropy of electronic transport properties of the n-type Pnma ***,the lattice thermal conductivity also exhibits anisotropic behavior under pressure due to a special collaged phonon *** pressure-induced lattice thermal conductivity along the a-axis shows a slower growth trend than that along the b-axis and *** optimal ZT value of the n-type Pnma SnSe along the a-axis can reach 1.64 at room *** results would be helpful for designing the Pnma SnSe-based materials for the potential thermoelectric and valleytronic applications.

关键词： first-principles calculations pressure SnSe thermoelectric materials