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LÉVY AREA ANALYSIS AND PARAMETER ESTIMATION FOR FOU PROCESSES VIA NON-GEOMETRIC ROUGH PATH THEORY

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Acta Mathematica Scientia 2024年第5期44卷 1609-1638页

作者： Zhongmin qian Xingcheng XU Mathematical Institute University of OxfordOxfordOX26GGUK Shanghai Artificial Intelligence Laboratory Shanghai200232China School of Mathematical Sciences Peking UniversityBeijing100871China

This paper addresses the estimation problem of an unknown drift parameter matrix for a fractional Ornstein-Uhlenbeck process in a multi-dimensional *** tackle this problem,we propose a novel approach based on rough path theory that allows us to construct pathwise rough path estimators from both continuous and discrete observations of a single *** approach is particularly suitable for high-frequency *** formulate the parameter estimators,we introduce a theory of pathwise Itôintegrals with respect to fractional Brownian *** establishing the regularity of fractional Ornstein-Uhlenbeck processes and analyzing the long-term behavior of the associated Lévy area processes,we demonstrate that our estimators are strongly consistent and pathwise *** findings offer a new perspective on estimating the drift parameter matrix for fractional Ornstein-Uhlenbeck processes in multi-dimensional settings,and may have practical implications for fields including finance,economics,and engineering.

关键词： Itôintegration Lévy area non-geometric rough path fOU processes pathwise stability long time asymptotic high-frequency data

Dexamethasone implant in naive versus refractory patients with diabetic macular edema:a Meta-analysis

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International Journal of Ophthalmology(English edition) 2024年第10期17卷 1898-1904页

作者： qian Xu Chao Yang Jie Luan Department of Ophthalmology Zhongda HospitalSoutheast UniversityNanjing 210009Jiangsu ProvinceChina School of Medicine Southeast UniversityNanjing 210009Jiangsu ProvinceChina

AIM:To evaluate the efficacy and safety of the intravitreal dexamethasone implant in naive and refractory patients with diabetic macular edema(DME).METHODS:PubMed,Embase,Web of Science,and Medline databases were *** main outcomes were best-corrected visual acuity(BCVA)and central retinal thickness(CRT).The secondary outcomes included mean number of injections,intraoperative or postoperative complications including intraocular pressure(IOP)elevation and ***:Ten comparative studies involving a total of 1.00 DME eyes including 402 naive eyes and 598 refractory eyes were *** postoperative BCVA in the naive group was significantly better than in the refractory group[mean difference(MD)-0.1.,95%confidence interval(CI)-0.1. to-0.05,P=0.0003;MD 8.69,95%CI 5.08 to 1..30,P1..Additionally,the naive group got greater improvement of BCVA change as well as more gains of BCVA letters than the refractory group[MD 7.71.95%CI 2.02 to 1..40,P=0.008;odds ratio(OR)2.99,95%CI 2.05 to 4.37,P1..The subgroup analysis revealed that the naive group had significantly higher BCVA gains of≥5,≥1.,and≥1. letters compared to the refractory group(P=0.002,0.0001.0.003,respectively).No significant difference was detected between the two groups in either postoperative CRT(MD-22.36,95%CI-46.39 to 1.66,P=0.07)or the overall mean number of injections(MD-0.08,95%CI-0.38 to 0.22,P=0.61..Intraoperative and postoperative complications including the elevation of IOP(OR 0.47,95%CI 0.20 to 1.1.,P=0.09)and cataract(OR 1.78,95%CI 0.97 to 3.24,P=0.06)showed no significant differences between the two groups during the follow-up ***:Intravitreal dexamethasone implants for DME can improve anatomical and functional outcomes in both naive and refractory eyes and have a well-acceptable safety ***,naive eyes maintain better visual outcomes than refractory *** provides further evidence of better visual response when used for naive eyes as firstline t

关键词： diabetic macular edema dexamethasone implant refractory eyes systemic review

Identification of fractional order Hammerstein models based on mixed signals

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Journal of Control and Decision 2024年第1期11卷 132-138页

作者： Mengqi Sun Hongwei Wang qian Zhang School of Control Science and Engineering Dalian University of TechnologyDalianPeople’s Republic of China School of Electrical Engineering Xinjiang UniversityUrumqiPeople’s Republic of China

An algorithm based on mixed signals is proposed,to solve the issues of low accuracy of identification algorithm,immeasurable intermediate variables of fractional order Hammerstein model,and how to determine the magnitude of fractional *** this paper,a special mixed input signal is designed to separate the nonlinear and linear parts of the fractional order Hammerstein model so that each part can be identified *** nonlinear part is fitted by the neural fuzzy network model,which avoids the limitation of polynomial fitting and broadens the application range of nonlinear *** addition,the multi-innovation Levenberg-Marquardt(MILM)algorithm and auxiliary recursive least square algorithm are innovatively integrated into the parameter identification algorithm of the fractional order Hammerstein model to obtain more accurate identification results.A simulation example is given to verify the accuracy and effectiveness of the proposed method.

关键词： Mixed signal fractional order Hammerstein model neural fuzzy network model multi-innovation Levenberg-Marquardt algorithm

Root-derived long-distance signals trigger ABA synthesis and enhance drought resistance in Arabidopsis

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Journal of Genetics and Genomics 2024年第7期51卷 749-761页

作者： qian-qian Liu Jin-Qiu Xia Jie Wu Yi Han Gui-Quan Zhang Ping-Xia Zhao Cheng-Bin Xiang Division of Life Sciences and Medicine Division of Molecular&Cell BiophysicsHefei National Science Center for Interdisciplinary Sciences at the MicroscaleUniversity of Science and Technology of ChinaThe Innovation Academy of Seed DesignChinese Academy of SciencesHefeiAnhui 230027China College of Life Sciences Anhui Agricultural UniversityHefeiAnhui 230036China College of Agronomy South China Agricultural UniversityGuangzhouGuangdong 510642China School of Biology and Basic Medical Sciences Soochow UniversitySuzhouJiangsu 215123China

Vascular plants have evolved intricate long-distance signaling mechanisms to cope with environmental stress,with reactive oxygen species(ROS)emerging as pivotal systemic signals in plant stress ***,the exact role of ROS as root-to-shoot signals in the drought response has not been *** this study,we reveal that compared with wild-type plants,ferric reductase defective 3(frd3)mutants exhibit enhanced drought resistance concomitant with elevated NINE-CIS-EPOXYCAROTENOID DIOXYGENASE 3(NCED3)transcript levels and abscisic acid(ABA)contents in leaves as well as increased hydrogen peroxide(H_(2)O_(2))levels in roots and *** experiments distinctly illustrate that drought resistance can be conferred by the frd3 rootstock regardless of the scion genotype,indicating that long-distance signals originating from frd3 roots promote an increase in ABA levels in ***,the drought resistance conferred by the frd3 mutant rootstock is weakened by the CAT2-overexpressing scion,suggesting that H_(2)O_(2)may be involved in long-distance ***,the results of comparative transcriptome and proteome analyses support the drought resistance phenotype of the frd3 *** together,our findings substantiate the notion that frd3 root-derived long-distance signals trigger ABA synthesis in leaves and enhance drought resistance,providing new evidence for root-to-shoot long-distance signaling in the drought response of plants.

关键词： frd3 Drought resistance Root-to-shoot long-distance signals Reactive oxygen species(ROS) H_(2)O_(2) Iron ABA

Research on Condenser Deterioration Evolution Trend Based on ANP-EWM Fusion Health Degree

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 679-698页

作者： Hong qian Haixin Wang Guangji Wang Qingyun Yan College of Automation Engineering Shanghai University of Electric PowerShanghai200090China Shanghai Key Laboratory of Power Station Automation Technology Shanghai200072China Empower Information Technology(Shanghai)Co. Ltd.Shanghai201508China China Nuclear Power Engineering Design Co. Ltd.Shenzhen518052China

This study presents a proposed method for assessing the condition and predicting the future status of condensers operating in seawater over an extended *** aim is to address the problems of scaling and corrosion,which lead to increased loss of cold *** method involves utilising a set of multivariate feature parameters associated with the condenser as input for evaluation and trend *** methodology offers a precise means of determining the optimal timing for condenser cleaning,with the ultimate goal of improving its overall *** proposed approach involves the integration of the analytic network process with subjective expert experience and the entropy weightmethod with objective big data analysis to develop a fusion health *** mathematical model is constructed quantitatively using the improved Mahalanobis ***,a comprehensive prediction model is developed by integrating the improved Informer model and Markov error *** model takes into account the health status of the equipment and several influencing factors,includingmultivariate feature *** model facilitates the objective examination and prediction of the progression of equipment deterioration *** present study involves the computation and verification of the field time series data,which serves to demonstrate the accuracy of the condenser health-related models proposed in this *** models effectively depict the real condition and temporal variations of the equipment,thus offering a valuable method for determining the precise cleaning time required for the condenser.

关键词： Condenser health degree improved Mahalanobis distance GC-Informer model Markov error correction

A new era of mutation rate analyses: Concepts and methods

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Zoological Research 2024年第4期45卷 767-780页

作者： Kun Wu Danqi Qin Yang qian Haoxuan Liu Center for Evolutionary&Organismal Biology and the Fourth Affiliated Hospital of Zhejiang University Zhejiang University School of MedicineHangzhouZhejiang 310058China

The mutation rate is a pivotal biological characteristic,intricately governed by natural selection and historically garnering considerable *** advances in high-throughput sequencing and analytical methodologies have profoundly transformed our understanding in this domain,ushering in an unprecedented era of mutation rate *** paper aims to provide a comprehensive overview of the key concepts and methodologies frequently employed in the study of mutation *** examines various types of mutations,explores the evolutionary dynamics and associated theories,and synthesizes both classical and contemporary ***,this review comprehensively explores recent advances in understanding germline and somatic mutations in animals and offers an overview of experimental methodologies,mutational patterns,molecular mechanisms,and driving forces influencing variations in mutation rates across species and ***,it proposes several potential research directions and pressing questions for future investigations.

关键词： Mutation rate Somatic mutations Germline mutations Animal

Spatio-Temporal Service Analysis in Multi-Layer Non-Terrestrial Networks

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Journal of Communications and Information Networks 2024年第1期9卷 43-55页

作者： qian Chen Weixiao Meng Shuai Han Cheng Li School of Electronics and Information Engineering Harbin Institute of TechnologyHarbin 150001China School of Engineering Science Simon Fraser UniversityBurnabyBC V5A 1S6Canada Department of Electrical and Computer Engineering Memorial UniversitySt.John’sNL A1B 3X5Canada

In the advent of the 6G era, non-terrestrial networks (NTN) with expansive coverage are being increasingly recognized as a vital supplement to cellular networks for facilitating seamless communication. The intricate interplay between network performance and service quality necessitates a thorough investigation into the modeling and analysis of services for efficient construction of *** studies on service analysis, predominantly focused on terrestrial networks,fall short in addressing the unique challenges posed by NTN,particularly those related to platform distribution and antenna gain modeling. This deficiency in research,coupled with the varying preferences of users for different network types, forms the basis of this study. This paper explores the spatio-temporal characteristics of services within a multi-layered NTN *** this context,the spatial distribution of the platforms is modeled using a binomial point process, and the antennas are characterized by a sectorized beam pattern. We derive the closed-form expressions for the association probability,the number of accessed users, and the arrival rate of services with certain delay requirements towards different types of NTN. Simulation results are provided to evaluate the influence of various parameters on the association probability, the number of accessed users, and the total arrival rate of services. The number of satellites can be determined to achieve the optimal system utility,balancing the accessed services, offloading effects, and launching costs. This initial investigation lays the groundwork for further theoretical progress in the service analysis and platform deployment of NTN.

关键词： association strategy non-terrestrial networks service analysis stochastic geometry system utility

Organo-electroreduction enables arylcarboxylation of styrenes

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Science China Chemistry 2024年第11期67卷 3825-3832页

作者： Yanwei Wang qian Wang Zile Zhu Weikang Qi Youai Qiu State Key Laboratory and Institute of Elemento-Organic Chemistry Frontiers Science Center for New Organic Matter Haihe Laboratory of Sustainable Chemical Transformations College of Chemistry Nankai University

Electroreduction offers an alternative to generate high active intermediates from electrophiles(halides, alkenes, etc.) in organic synthesis. However, it still remains challenge to enable the transformations in controlled fashion for substrates with similar reduction potentials. Herein, an electroreductive arylcarboxylation of styrenes with aryl halides and CO2promoted by an organomediator has been developed. The reaction exhibits the remarkable reactivity control between styrenes and aryl halides bearing very similar reduction potentials, which is enabled by the addition of a simple organic mediator. The mediated process for different kinds of aryl halides(iodides and bromides) could be achieved by simply tuning the electronic effect of the skeleton of naphthalene. This protocol displays a broad substrate scope and the extension to late-stage modification of biorelevant molecules and their derivatives showed a bright prospect. Moreover, density functional theory(DFT) calculations and mechanistic studies have been conducted and provide solid support to rationalize the selectivity and reactivity control observed.

关键词： CO2 utilization reductive organo-mediator carboxylation electroreduction aryl halides

Grow rice under sunshine of Xizang/Tibet:promise and challenges

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Journal of Genetics and Genomics 2024年第3期51卷 265-267页

作者： Chunkun Fan Xiaoming Zheng Qingbo Yuan Tao Wang qian qian Qingyun Bu Fan Chen Agricultural Institute Xizang Academy of Agricultural and Animal Husbandry ScienceLasaXizang 850032China National Key Facility for Crop Gene Resources and Genetic Improvement Institute of Crop SciencesChinese Academy of AgriculturalSciencesBeijing 100081China Sanya National Research Institute of Breeding in Hainan Chinese Academy of Agricultural SciencesBeijing 572000China Yazhouwan National Laboratory SanyaHainan 572704China Chengdu Institute of Biology Chinese Academy of SciencesChengduSichuan 610041China Northeast Institute of Geography and Agroecology Chinese Academy of SciencesHarbinHeilongjiang 150081China

Xizang,previously known as Tibet,is located in the southwest region of China and is the highest region of the Qinghai-Tibet Plateau(QzP),with an average altitude of over 4000 *** the development of modern agriculture,the grain productivity in Xizang has been effectively *** total annual grain production has increased from 558,700 tons in 1.88 to 1.44,000 tons in 201.(Xizang Statistical Year Book).

关键词： sunshine Tibet southwest