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Some Convergence Properties for Weighted Sums of Martingale Difference Random Vectors

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Acta Mathematica Sinica,English Series 2024年第4期40卷 1127-1142页

作者： Yi WU xue Jun WANG School of Big Data and Artificial Intelligence Chizhou UniversityChizhou 247000P.R.China School of Big Data and Statistics Anhui UniversityHefei 230601P.R.China

Let{X_(ni),F_(ni);1≤i≤n,n≥1}be an array of R^(d)martingale difference random vectors and{A_(ni),1≤i≤n,n≥1}be an array of m×d matrices of real *** this paper,the Marcinkiewicz-Zygmund type weak law of large numb... 详细信息

关键词： Martingale difference random vectors weighted sums Marcinkiewicz–Zygmund type weak law of large numbers complete convergence strong law of large numbers multivariate simple linear regression model

Elevation of basal lacustrine sediments along the mid-lower reaches of the Yangtze River and its implications for the reconstruction of Holocene water levels

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Science China Earth Sciences 2024年第9期67卷 2924-2936页

作者： Shuchun YAO Chunhai LI Bin xue Nanjing Institute of Geography and Limnology Chinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China

The middle and lower reaches of the Yangtze River,a primary region for freshwater lakes in China,have undergone significant transformations throughout the *** changes,driven by factors such as sea-level rise,climate change,and human activities,have led to the progressive elevation of water levels in this *** a result,a floodplain has emerged,characterized by the formation of numerous shallow lakes along the river ***,the pattern of water-level changes in the main channel of the Yangtze River during the Holocene remains *** gap in knowledge poses challenges for understanding sediment transport dynamics,the interactions between the river and its adjacent lakes,and the prevention and control of flood disasters in the Yangtze River *** shed light on these issues,our study compiled data on the surface elevation and water depth of 81 lakes in the mid-lower reaches of the Yangtze River ***,we analyzed historical water-level records from the 1900s to the 1970s at eight gauging stations from Shashi to Jiangyin along the river’s main *** findings reveal that,particularly along the Jingjiang section,the basal elevation of most lakes is lower than the Yangtze River’s water level during the dry ***,the water level of the main stream exceeds that of both the floodplain and the lakes enclosed by the Jingjiang *** the tidal reach,especially within the Taihu Lake basin,the basal elevation of lakes typically falls below sea ***,lakes located along the section from Chenglingji to Wuhu exhibit basal elevations that correspond with the Yangtze River’s annual average and dry season water *** the widespread presence of lakes along the middle and lower reaches of the Yangtze River,our study introduces a new proxy for reconstructing the mean water level of the mid-lower Yangtze River in the *** analyzing sediments from Nanyi Lake and Chenyao Lake in the lower Yangtze River,we a

关键词： Middle and lower Yangtze River Holocene Water level Floodplain lakes Basal sediment elevation

Sample Generation for Security Region Boundary Identification Based on Topological Features of Historical Operation Data

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1087-1095页

作者： Xiaokang Wu Wei Xu Feng xue College of Energy and Electrical Engineering Hohai UniversityNanjingChina NARI Group Corporation NanjingChina State Grid Electric Power Research Institute NanjingChina

Since the scale and uncertainty of the power sys-tem have been rapidly increasing,the computation efficiency of constructing the security region boundary(SRB)has become a prominent *** on the topological features of histori-cal operation data,a sample generation method for SRB identi-fication is proposed to generate evenly distributed samples,which cover dominant security *** boundary sample pair(BSP)composed of a secure sample and an unsecure sam-ple is defined to describe the feature of *** resolution,sampling,and span indices are designed to evaluate the cover-age degree of existing BSPs on the SRB and generate samples closer to the *** on the feature of flat distribution of BSPs over the SRB,the principal component analysis(PCA)is adopted to calculate the tangent vectors and normal vectors of ***,the sample distribution can be expanded along the tangent vector and corrected along the normal vector to cover different security ***,a sample set is randomly gen-erated based on the IEEE standard example and another new sample set is generated by the proposed *** results in-dicate that the new sample set is closer to the SRB and covers different security modes with a small calculation time cost.

关键词： Clustering analysis principal component analysis(PCA) sample generation security region boundary(SRB)

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活塞环表面处理及摩擦学性能研究进展

电镀与涂饰 2020年第21期39卷 1510-1513页

作者：薛茂权黄之德倪贵华杨峰王乾常州工业职业技术学院江苏常州213164 全椒雷科德精密机械有限公司安徽全椒239500

总结了活塞环表面电镀铬、喷涂、物理气相沉积、类金刚石涂层等表面处理技术的研究进展及其耐磨减摩性能,并指出了各种方法的优、缺点,对活塞环表面处理的研发提出了建议。

关键词：活塞环摩擦学电镀铬喷涂物理气相沉积类金刚石层综述

Open-Shell Oligomers and Polymers: Theory, Characterization Methods, Molecular Design, and Applications

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Chinese Journal of Polymer Science 2024年第4期42卷 417-436页

作者： xue-Qing Wang Cheng Song Ting Lei Key Laboratory of Polymer Chemistry and Physics(Ministry of Education) School of Materials Science and EngineeringPeking UniversityBeijing100871China

Open-shell oligomers and polymers have exhibited intriguing electronic and magnetic properties, making them highly desirable for a wide range of applications, including ambipolar organic field-effect transistors (OFETs), photodetectors, organic thermoelectrics, and spintronics. Although open-shell ground states have been observed in certain small molecules and doped organic semiconductors, the exploration of open-shell ground-state conjugated polymers is still limited, and the strategies for designing these polymers remain obscure. This review aims to briefly introduce the theory and characterization methods of open-shell conjugated polymers, along with an overview of recent progress and applications. The objective is to stimulate further advancements and investigations in this promising area by shedding light on the potential of open-shell conjugated polymers and the challenges that lie ahead.

关键词： Conjugated polymers Open-shell molecules High-spin ground state Donor-acceptor(D-A)polymers Optoelectronic and magnetic properties

Classification,biosynthesis,and biological functions of triterpene esters in plants

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Plant Communications 2024年第4期5卷 67-93页

作者： Jia Liu xue Yin Chengxi Kou Ramesha Thimmappa Xin Hua Zheyong xue Key Laboratory of Saline-alkali Vegetation Ecology Restoration(Northeast Forestry University) Ministry of EducationHarbin 150040China Heilongjiang Key Laboratory of Plant Bioactive Substance Biosynthesis and Utilization Northeast Forestry UniversityHarbin 150040China Amity Institute of Genome Engineering Amity UniversityNoidaUP India 201313India State Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs Beijing 100700P.R.China

Triterpene esters comprise a class of secondary metabolites that are synthesized by decorating triterpene skeletons with a series of oxidation,glycosylation,and acylation *** triterpene esters with important bioactivities have been isolated and identified,including those with applications in the pesticide,pharmaceutical,and cosmetic *** also play essential roles in plant defense against pests,dis-eases,physical damage(as part of the cuticle),and regulation of root ***,there has been no recent summary of the biosynthetic pathways and biological functions of plant triterpene ***,we classify triterpene esters intofive categories based on their skeletons andfind that C-3 oxidation may have a significant effect on triterpenoid *** acid and aromatic moieties are common li-gands present in triterpene *** further analyze triterpene ester synthesis-related acyltransferases(TEsACTs)in the triterpene biosynthetic *** an evolutionary classification of BAHD acyltrans-ferases(BAHD-ATs)and serine carboxypeptidase-like acyltransferases(SCPL-ATs)in Arabidopsis thaliana and Oryza sativa,we classify 18 TEsACTs with identified functions from 11 *** the triterpene-skel-eton-related TEsACTs belong to BAHD-AT clades IIIa and I,and the only identified TEsACT from the SCPL-AT family belongs to the CP-I *** comprehensive review of the biosynthetic pathways and bioactivities of triterpene esters provides a foundation for further study of their bioactivities and applica-tions in industry,agricultural production,and human health.

关键词： triterpene esters acyltransferases classification biosynthesis biological functions

Voltage-modulated polymer nanopore field-effect transistor for multi-sized nanoparticle detection

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Nanotechnology and Precision Engineering 2024年第3期7卷 79-89页

作者： Feng Zhou Lin Li Qiannan xue State Key Laboratory of Precision Measurement Technology and Instruments School of Precision Instruments and Optoelectronics EngineeringTianjin UniversityTianjin 300072China

Solid-state nanopores offer a range of distinct advantages over biological nanopores,such as structural diversity and greater stability and durability;this makes them highly promising for high-resolution nanoparticle *** nanopores can exhibit gating characteristics with stress-responsive switches and can demonstrate specificity toward particular *** inspiration from biological nanopores,this paper introduces a novel polymer nanopore with field-effect characteristics,leveraging a conductive polymer in its construction to showcase intriguing gating ***,in this device,the polymer layer serves as the gate,enabling precise control over the source–drain current response inside and outside the pore by simply adjusting the gate *** unique feature allows fine-tuning of the nanopore’s sensitivity to nanoparticles of varying sizes and facilitates its operation in multiple *** results reveal that the developed polymer nanopore field-effect transistor demonstrates remarkable selectivity in detecting nanoparticles of various sizes under different applied *** proposed single device demonstrates the exceptional ability to detect multiple types of nanoparticle,showcasing its immense potential for a wide range of applications in biological-particle analysis and medical diagnostics.

关键词： Nanopipette Polymer nanopore Voltage modulation Nanoparticle detection

Effects of microenvironment and biological behavior on the paracrine function of stem cells

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Genes & Diseases 2024年第1期11卷 135-147页

作者： Zhixin xue Yunjun Liao Ye Li The Department of Plastic and Cosmetic Surgery Nanfang HospitalSouthern Medical UniversityGuangzhouGuangdong 510515China

Mesenchymal stem cells(MSCs),the most well-studied cell type in the field of stem cell therapy,have multi-lineage differentiation and self-renewal ***-based thera-pies have been used to treat diverse diseases because of their ability to potently repair tissue and locally restore *** increasing body of evidence demonstrates that paracrine func-tion is central to the effects of MsC-based *** factors,cytokines,chemokines,extracellular matrix components,and extracellular vehicles all contribute to the beneficial ef-fects of MSCs on tissue regeneration and *** paracrine substances secreted by MSCs change depending on the tissue microenvironment and biological *** this review,we discuss the bioactive substances secreted by MsCs depending on the microenvironment and biological behavior and their regulatory mechanisms,which explain their potential to treat human diseases,to provide new ideas for further research and clinical cell-free therapy.

关键词： Bioactive behavior Mesenchymal stem cells Microenvironment Paracrine Secretome

Comparison of a Spectral Bin and Two Multi-Moment Bulk Microphysics Schemes for Supercell Simulation:Investigation into Key Processes Responsible for Hydrometeor Distributions and Precipitation

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Advances in Atmospheric Sciences 2024年第5期41卷 784-800页

作者： Marcus JOHNSON Ming xue Youngsun JUNG Center for Analysis and Prediction of Storms University of OklahomaNormanOK 73072USA School of Meteorology University of OklahomaNormanOK 73072USA Office of Science and Technology Integration National Weather ServiceSilver SpringMD 20910USA

There are more uncertainties with ice hydrometeor representations and related processes than liquid hydrometeors within microphysics parameterization(MP)schemes because of their complicated geometries and physical *** supercell simulations are produced using the WRF model coupled with“full”Hebrew University spectral bin MP(HU-SBM),and NSSL and Thompson bulk MP(BMP)***-SBM downdrafts are typically weaker than those of the NSSL and Thompson simulations,accompanied by less rain ***-SBM produces more cloud ice(plates),graupel,and hail than the BMPs,yet precipitates less at the *** limiting mass bins(and subsequently,particle size)of rimed ice in HU-SBM and slower rimed ice fall speeds lead to smaller melting-level net rimed ice fluxes than those of the *** from plates in HU-SBM,together with snow–graupel collisions,leads to a greater snow contribution to rain than those of the *** HU-SBM’s fall speeds using the formulations of the BMPs after aggregating the discrete bin values to mass mixing ratios and total number concentrations increases net rain and rimed ice ***,they are smaller in magnitude than bulk rain,NSSL hail,and Thompson graupel net fluxes near the ***,the melting-layer net rimed ice fluxes are reduced when the fall speeds for the NSSL and Thompson simulations are calculated using HU-SBM fall speed formulations after discretizing the bulk particle size distributions(PSDs)into spectral *** results highlight precipitation sensitivity to storm dynamics,fall speed,hydrometeor evolution governed by process rates,and MP PSD design.

关键词： precipitation spectral bin microphysics bulk microphysics parameterization microphysics processes WRF model supercell storm