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Coupled effects of climate change and human activities on vegetation dynamics in the Southwestern Alpine Canyon Region of China

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Journal of Mountain Science 2024年第10期21卷 3234-3248页

作者： lai Jinlin QI Shi School of Soil and Water Conservation Beijing Forestry UniversityBeijing 100083China

The driving effects of climate change and human activities on vegetation change have always been a focal point of ***,the coupling mechanisms of these driving factors across different temporal and spatial scales remain *** Southwestern Alpine Canyon Region of China(SACR),as an ecologically fragile area,is highly sensitive to the impacts of climate change and human *** study constructed a vegetation cover dataset for the SACR based on the Enhanced Vegetation Index(EVI)from 2000 to *** autocorrelation,Theil-Sen trend,and Mann-Kendall tests were used to analyze the spatiotemporal characteristics of vegetation cover *** main drivers of spatial heterogeneity in vegetation cover were identified using the optimal parameter geographic detector,and an improved residual analysis model was employed to quantify the relative contributions of climate change and human activities to interannual vegetation cover *** main findings are as follows:Spatially,vegetation cover exceeds 60%in most areas,especially in the southern part of the study ***,the border area between Linzhi and Changdu exhibits lower vegetation *** factors are the primary drivers of spatial heterogeneity in vegetation cover,with temperature having the most significant influence,as indicated by its q-value,which far exceeds that of other ***,the interaction q-value between the two factors significantly increases,showing a relationship of bivariate enhancement and nonlinear *** terms of temporal changes,vegetation cover shows an overall improving trend from 2000 to 2020,with significant increases observed in 68.93%of the study *** these,human activities are the main factors driving vegetation cover change,with a relative contribution rate of 41.31%,while climate change and residual factors contribute 35.66%and 23.53%,*** thoroughly exploring the coupled mechanisms of vegetation change,this

关键词： Enhanced vegetation index Climate change Human activities Spatial heterogeneity Coupled mechanisms

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Relationship between structure and microwave dielectric properties of Li_(3)Mg_(4)Nb_(1-x)Ta_(x)O_(8)ceramics

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Journal of Materiomics 2024年第1期10卷 245-252页

作者： Chongsheng Wu Kui Liu Honglan lai Fang Xu School of Mechanical and Electrical Engineering Chengdu University of TechnologyChengduSichuan610059China School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu610054China State Key Laboratory of Environment-friendly Energy Materials Southwest University of Science and TechnologyMianyang621010China

Herein,the sintering behavior and dielectric properties of Ta5+-doped Li3Mg4NbO8 ceramics were investigated by solid-phase reactions in combination with first-principles *** particular,Li_(3)Mg_(4)Nb_(0.96)Ta_(0.04)O_(8)illustrates the best dielectric properties after sintering at 1,175℃withεr=13.71±0.20,Q×f=(132,112±2,391)GHz(increased by 25%)andτf=(25.07±1.36)×10^(−6)℃^(−1).The non-intrinsic factors reflect that a small amount of Ta^(5+)doping produces a secondary phase,increased densification,and grain size,all of which optimize the dielectric *** dominant intrinsic factors indicate that the increase in bond ionicity,the greater polarization of Ta^(5+),and the blueshift of the Raman characteristic peak all lead to an increase inε*** increase in lattice energy and the decrease in the damping behavior of the Nb/Ta-O bond vibrations lead to an increase in Q×*** weakening of the Nb/TaO_(6) octahedral distortion leads to an optimization ofτ*** modified Li_(3)Mg_(4)Nb_(0.96)Ta_(0.04)O_(8) ceramics have promising applications in microwave communications.

关键词： First-principles Li_(3)Mg_(4)NbO_(8),dielectric properties Lattice vibration

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Benchmarking visual SLAM methods in mirror environments

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Computational Visual Media 2024年第2期10卷 215-241页

作者： Peter Herbert Jing Wu Ze Ji Yu-Kun lai School of Computer Science and Informatics Cardiff UniversityAbacws BuildingSenghennydd RdCardiff CF244AGUK School of Engineering Cardiff UniversityQueen’s BuildingsThe ParadeCardiff CF243AAUK

Visual simultaneous localisation and mapping(vSLAM)finds applications for indoor and outdoor navigation that routinely subjects it to visual complexities,particularly mirror *** effect of mirror presence(time visible and its average size in the frame)was hypothesised to impact localisation and mapping performance,with systems using direct techniques expected to perform ***,a dataset,MirrEnv,of image sequences recorded in mirror environments,was collected,and used to evaluate the performance of existing representative *** ORB-SLAM3 and BundleFusion appear to show moderate degradation of absolute trajectory error with increasing mirror duration,whilst the remaining results did not show significantly degraded localisation *** mesh maps generated proved to be very inaccurate,with real and virtual reflections colliding in the reconstructions.A discussion is given of the likely sources of error and robustness in mirror environments,outlining future directions for validating and improving vSLAM performance in the presence of planar *** MirrEnv dataset is available at https://***/10.17035/d.2023.0292477898.

关键词： visual simultaneous localisation and mapping(vSLAM) mirror localisation mapping reflection datase

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Non-uniform thermal behavior of single-layer spherical reticulated shell structures considering time-variant environmental factors: analysis and design

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第3期25卷 223-237页

作者： Wucheng XU Xiaoqing ZHENG Xuanhe ZHANG Zhejie lai Yanbin SHEN College of Civil Engineering and Architecture Zhejiang UniversityHangzhou 310058China Center for Balance Architecture Zhejiang UniversityHangzhou 310028China Innovation Center of Yangtze River Delta Zhejiang UniversityJiaxing 314100China Zhejiang Provincial Key Laboratory of Space Structures Zhejiang UniversityHangzhou 310058China

Contrary to conventional design methods that assume uniform and slow temperature changes tied to atmospheric conditions,single-layer spherical reticulated shells undergo significant non-uniform and time-variant temperature variations due to dynamic environmental *** differences can affect structural performance and pose safety ***,a systematic numerical method was developed and applied to simulate long-term temperature variations in such a structure under real environmental conditions,revealing its non-uniform distribution characteristics and time-variant regularity.A simplified design method for non-uniform thermal loads,accounting for time-variant environmental factors,was theoretically derived and validated through experiments and *** maximum deviation and mean error rate between calculated and tested results were 6.1℃ and 3.7%,*** temperature fields aligned with simulated ones,with deviations under 6.0℃.Using the design method,non-uniform thermal effects of the structure are *** member stress and nodal displacement under non-uniform thermal loads reached 119.3 MPa and 19.7 mm,representing increases of 167.5%and 169.9%,respectively,compared to uniform thermal *** impacts of healing construction time on non-uniform thermal effects were evaluated,resulting in construction *** methodologies and conclusions presented here can serve as valuable references for the thermal design,construction,and control of single-layer spherical reticulated shells or similar structures.

关键词： Non-uniform temperature field Non-uniform thermal load Non-uniform thermal effect Single-layer spherical reticulated shell Time-variant environmental factor

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Enhanced Fenton-like process over Cu/L(+)-ascorbic acid co-doping mesoporous silica for toxicity reduction of emerging contaminants

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Frontiers of Environmental Science & Engineering 2024年第4期18卷 49-60页

作者： Yuhang Liu Wenxuan Deng Xiaojun Wu Chun Hu lai Lyu Key Laboratory for Water Quality and Conservation of the Pearl River Delta(Ministry of Education) Institute of Environmental Research at Greater BayGuangzhou UniversityGuangzhou 510006China

Effective removal of emerging contaminants(ECs)to minimize their impacts on human health and the natural environment is a global *** the removal of ECs in water,we fabricated a seaweed spherical microsphere catalyst with Cu cation-πstructures by in situ doping of Cu species and ascorbic acid in mesoporous silica(Cu-C-MSNs)via a hydrothermal *** results indicate that bisphenol A(BPA)is substantially degraded within 5 min under natural conditions,with its biological toxicity considerably ***,industrial wastewater could also be effectively purified by Cu-C-MSNs/H_(2)O_(2) *** presence of metal sites and the complexation of ECs via cation-πinteraction andπ-πstacking on the catalyst surface were directly responsible for the polarization distribution of electrons,thus activating H_(2)O_(2) and dissolved oxygen(DO).The removal of contaminants could be attributed primarily to 1)the activation of H_(2)O_(2) into ^(·)OH to attack the contaminants and 2)self-cleavage because of the transfer of electrons from the contaminants to the *** study provides an innovative solution for the effective treatment of ECs and has positive implications for easing global environmental crises.

关键词： Cation-πstructures Polarization electric field Fenton-like process Contaminants cleavage

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Dynamics and vibration reduction performance of asymmetric tristable nonlinear energy sink

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 389-406页

作者： Hongyan CHEN Youcheng ZENG Hu DING Siukai lai Liqun CHEN School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Frontier Science Center of MechanoinformaticsShanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200444China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityKowloonHong KongChina

With its complex nonlinear dynamic behavior,the tristable system has shown excellent performance in areas such as energy harvesting and vibration suppression,and has attracted a lot of *** this paper,an asymmetric tristable design is proposed to improve the vibration suppression efficiency of nonlinear energy sinks(NESs)for the first *** proposed asymmetric tristable NES(ATNES)is composed of a pair of oblique springs and a vertical ***,the three stable states,symmetric and asymmetric,can be achieved by the adjustment of the distance and stiffness asymmetry of the oblique *** governing equations of a linear oscillator(LO)coupled with the ATNES are *** approximate analytical solution to the coupled system is obtained by the harmonic balance method(HBM)and verified *** vibration suppression efficiency of three types of ATNES is *** results show that the asymmetric design can improve the efficiency of vibration reduction through comparing the chaotic motion of the NES oscillator between asymmetric steady *** addition,compared with the symmetrical tristable NES(TNES),the ATNES can effectively control smaller structural *** other words,the ATNES can effectively solve the threshold problem of TNES failure to weak ***,this paper reveals the vibration reduction mechanism of the ATNES,and provides a pathway to expand the effective excitation amplitude range of the NES.

关键词： asymmetric nonlinear energy sink(NES) tristable vibration control po-tential barrier

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A booming field of large animal model research

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Zoological Research 2024年第2期45卷 311-313页

作者： Xiao-Jiang Li Liangxue lai Guangdong Key Laboratory of Non-human Primate Research Key Laboratory of CNS Regeneration(Ministry of Education)GHM Institute of CNS RegenerationJinan UniversityGuangzhouGuangdong 510632China State Key Laboratory of Bioactive Molecules and Druggability Assessment Jinan UniversityGuangzhouGuangdong 510632China CAS Key Laboratory of Regenerative Biology Guangdong Provincial Key Laboratory of Stem Cell and Regenerative MedicineGuangzhou Institutes of Biomedicine and HealthChinese Academy of SciencesGuangzhouGuangdong 510530China

Animal models are integral to the study of fundamental biological processes and the etiology of human *** animal models,especially those involving mice,have yielded abundant and significant insights,greatly enhancing ... 详细信息

关键词： mechanisms insight field

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Mechanical property of cylindrical sandwich shell with gradient core of entangled wire mesh

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Defence Technology（防务技术） 2024年第1期31卷 510-522页

作者： Xin Xue Chao Zheng Fu-qiang lai Xue-qian Wu Institute of Metal-rubber&Vibration Noise School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou350116China Fujian Metallurgical Industry Design Institute Fuzhou350116China

To explore the wide-frequency damping and vibration-attenuation performances in the application of aerospace components,the cylindrical sandwich shell structure with a gradient core of entangled wire mesh was proposed in this ***,the gradient cores of entangled wire mesh in the axial and radial directions were prepared by using an in-house Numerical Control weaving machine,and the metallurgical connection between skin sheets and the gradient core was performed using vacuum ***,to investigate the mechanical properties of cylindrical sandwich shells with axial or radial gradient cores,quasi-static and dynamic mechanical experiments were carried *** primary evaluations of mechanical properties include secant stiffness,natural frequency,Specific Energy Absorption(SEA),vibration acceleration level,and so *** results suggest that the vibration-attenuation performance of the sandwich shell is remarkable when the high-density core layer is at the end of the shell or abuts the inner *** axial gradient material has almost no influence on the vibration frequencies of the shell,whereas the vibration frequencies increase dramatically when the high-density core layer approaches the ***,compared to the conventional sandwich shells,the proposed functional grading cylindrical sandwich shell exhibits more potential in mass reduction,stiffness designing,and energy dissipation.

关键词： Entangled wire mesh Gradient cylindrical sandwich shell Vacuum brazing Secant stiffness Damping

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XMe - Xiamen Molecular Electronics Code:An Intelligent and Open-Source Data Analysis Tool for Single-Molecule Conductance Measurements

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Chinese Journal of Chemistry 2024年第3期42卷 317-329页

作者： Zhichao Pan Gang dong Chi Shang Ruihao Li Tengyang Gao Luchun Lin Huicong Duan Xiaohui Li Jie Bai Yilin lai Wenfeng Wu Jia Shi Junyang Liu Wenjing Hong State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering & Institute of Artificial IntelligenceXiamen UniversityXiamenFujian361005 China School of Artificial Intelligence Guilin University of Electronic TechnologyGuilinGuangxi541004 China

Charge transport characterization of single-molecule junctions is essential for the fundamental research of single-molecule physical chemistry and the development towards single-molecule electronic devices and circuits. Among the single-molecule conductance characterization techniques,the single-molecule break junction technique is widely used in tens of worldwide research laboratories which can generate a large amount of experimental data from thousands of individual measurement cycles. However,data interpretation is a challenging task for researchers with different research backgrounds,and the different data analysis approaches sometimes lead to the misunderstanding of the measurement data and even reproducibility issues of the measurement. It is thus a necessity to develop a user-friendly all-in-one data analysis tool that automatizes the basic data analysis in a standard and widely accepted way. In this work,we present the XMe Code (Xiamen Molecular Electronics Code),an intelligent all-in-one data analysis tool for the comprehensive analysis of single-molecule break junction data. XMe code provides end-to-end data analysis that takes in the original experimental data and returns electronic characteristics and even charge transport mechanisms. We believe that XMe Code will promote the transparency of the data analysis in single-molecule electronics and the collaborations among scientists with different research backgrounds.

关键词： Molecular electronics Single-molecule studies Break junction Data science Software

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Bat-derived oligopeptide LE6 inhibits the contact-kinin pathway and harbors anti-thromboinflammation and stroke potential

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Zoological Research 2024年第5期45卷 1001-1012页

作者： Li-Na Cha Juan Yang Jin-Ai Gao Xin Lu Xiao-Long Chang Rebecca Caroline Thuku Qi Liu Qiu-Min Lu dong-Sheng Li Ren lai Ming-Qian Fang Engineering Laboratory of Peptides of Chinese Academy of Sciences Key Laboratory of Bioactive Peptides of Yunnan ProvinceKIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common DiseasesNational Resource Center for Non-Human PrimatesNational Research Facility for Phenotypic&Genetic Analysis of Model Animals(Primate Facility)Key Laboratory of Genetic Evolution&Animal ModelsSino-African Joint Research Centerand New Cornerstone Science LaboratoryKunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650201China School of Molecular Medicine Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhouZhejiang 310024China First Affiliated Hospital of Kunming Medical University KunmingYunnan 650032China

Thrombosis and inflammation are primary contributors to the onset and progression of ischemic *** contact-kinin pathway,initiated by plasma kallikrein(PK)and activated factor XII(FXIIa),functions bidirectionally with the coagulation and inflammation cascades,providing a novel target for therapeutic drug development in ischemic *** this study,we identified a bat-derived oligopeptide from Myotis myotis(Borkhausen,1797),designated LE6(Leu-Ser-Glu-Glu-Pro-Glu,702 Da),with considerable potential in stroke therapy due to its effects on the contact kinin ***,LE6 demonstrated significant inhibitory effects on PK and FXIIa,with inhibition constants of 43.97μmol/L and 6.37μmol/L,*** vitro analyses revealed that LE6 prolonged plasma recalcification time and activated partial thromboplastin *** murine models,LE6 effectively inhibited carrageenan-induced mouse tail thrombosis,FeCl3-induced carotid artery thrombosis,and photochemically induced intracerebral ***,LE6 significantly decreased inflammation and stroke injury in transient middle cerebral artery occlusion ***,the low toxicity,hemolytic activity,and bleeding risk of LE6,along with its synthetic simplicity,underscore its clinical *** conclusion,as an inhibitor of FXIIa and PK,LE6 offers potential therapeutic benefits in stroke treatment by mitigating inflammation and preventing thrombus formation.

关键词： PK FXIIa Anti-thromboinflammation Ischemic stroke therapies Oligopeptide

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