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Molecular Plant 2024年第1期17卷 4-7页

作者： Mengqiu Song Wumei Wang Chun Ji Shengnan Li Wei Liu Xiaoyu Hul Anhui Feng Shuang Ruan shiyun du Huan Wang Kui Dai Longbiao Guo Qian Qian Hongqi Si Xingming Hu College of Agronomy Anhui Agricultural UniversityHefeiAnhui 230036China State Key Laboratory of Rice Biology China National Rice Research InstituteHangzhouZhejiang 310006China Rice Research Institute Anhui Academy of Agricultural SciencesHefeiAnhui 230031China Jiangxi Modern Seed Industry Co.NanchangJiangxi 330026China

Dear Editor,Utilization of heterosis is fundamental to modern agricultural improvement and contributes significantly to food security and agricultural development(Ouyang et al.,2022).However,heterosis of F,hybrids cannot be stably inherited.Apomixis,or asexual reproduction through seeds,offers the potential for the fixation of heterosis in F,hybrids and the formation of clonal offspring,which could have considerable implications for plant breeding and agriculture(Schmidt,2020).But naturally occurring apomixis has never been found in major crops.Recently,synthetic apomixis has been successfully generated by inducing incomplete meiotic development combined with parthenogenesis development to produce cloned rice(Oryza sativa)seeds(Khanday et al.,2019;Wang et al.,2019;Vernet et al.,2022;Wei et al.,2023).

关键词： sativa fertility breeding

An Adaptive Program Recommendation System for Multi-User Sharing Environment

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China Communications 2024年第6期21卷 112-128页

作者： Sun shiyun Hu Zhengying Wei Xin Zhou Liang School of Communications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China

More and more accounts or devices are shared by multiple users in video applications,which makes it difficult to provide recommendation service.Existing recommendation schemes overlook multiuser sharing scenarios,and they cannot make effective use of the mixed information generated by multi-user when exploring users’potential interests.To solve these problems,this paper proposes an adaptive program recommendation system for multi-user sharing environment.Specifically,we first design an offline periodic identification module by building multi-user features and periodically predicting target user in future sessions,which can separate the profile of target user from mixed log records.Subsequently,an online recommendation module with adaptive timevarying exploration strategy is constructed by jointly using personal information and multi-user social information provided by identification module.On one hand,to learn the dynamic changes in user-interest,a time-varying linear upper confidence bound(LinUCB)based on personal information is designed.On the other hand,to reduce the risk of exploration,a timeinvariant LinUCB based on separated multi-user social information from one account/device is proposed to compute the quality scores of programs for each user,which is integrated into the time-varying LinUCB by cross-weighting strategy.Finally,experimental results validate the efficiency of the proposed scheme.

关键词： adaptive exploitation LinUCB multiuser recommendation system

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System Strength Assessment Based on Multi-task Learning

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 41-50页

作者： Baoluo Li shiyun Xu Huadong Sun Zonghan Li Lin Yu Key Laboratory of Power System Intelligent Dispatch and Control of Ministry of Education Shandong UniversityJinan 250014China China Electric Power Research Institute Beijing 100192China

Increase in permeability of renewable energy sources(RESs)leads to the prominent problem of voltage stability in power system,so it is urgent to have a system strength evaluation method with both accuracy and practicability to control its access scale within a reasonable range.Therefore,a hybrid intelligence enhancement method is proposed by combining the advantages of mechanism method and data driven method.First,calculation of critical short circuit ratio(CSCR)is set as the direction of intelligent enhancement by taking the multiple renewable energy station short circuit ratio as the quantitative indicator.Then,the construction process of CSCR dataset is proposed,and a batch simulation program of samples is developed accordingly,which provides a data basis for subsequent research.Finally,a multi-task learning model based on progressive layered extraction is used to simultaneously predict CSCR of each RESs connection point,which significantly reduces evaluation error caused by weak links.Predictive performance and anti-noise performance of the proposed method are verified on the CEPRI-FS-102 bus system,which provides strong technical support for real-time monitoring of system strength.

关键词： Critical short circuit ratio hybrid intelligence enhancement multi-task learning system strength

Large-disturbance Stability Analysis of Power Systems with Synchronous Generator and Converter-interfaced Generation

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 997-1002页

作者： Lei Chen Yong Min Liangshuai Hao Guangzheng Xing Yalou Li shiyun Xu IEEE Department of Electrical Engineering Tsinghua University China Electric Power Research Institute

This letter studies large-disturbance stability of the power system with a synchronous generator(SG) and a converter-interfaced generation(CIG) connected to infinite bus. The power system is multi-timescale and first simplified. It is shown that the boundary of region of attraction(ROA) of the simplified model is composed of stable manifolds of unstable equilibrium point(UEP) or semi-singular point(SSP), named anchor points, and singular surface pieces. The type of anchor point determines the dominant instability pattern of the power system. When the anchor point is UEP or SSP, the dominant instability pattern is the instability of rotor angle of SG or the instability of phase-locked loop and outer control loop(OCL) of CIG, respectively. Transition of dominant instability pattern can be analyzed with the relative position relationship between UEP and SSP. The effect of OCL is discussed. When the OCL is activated, the ROA becomes smaller and the system is more prone to instability of CIG. It is necessary to consider the OCL when studying the large-disturbance stability of the power system.

关键词： Power system stability Mathematical models Phase locked loops Stability criteria Transient analysis Power system dynamics Rotors

Efficient Polytelluride Anchoring for Ultralong-Life Potassium Storage: Combined Physical Barrier and Chemisorption in Nanogrid-in-Nanofiber

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Nano-Micro Letters 2024年第4期16卷 364-378页

作者： Qinghua Li Dandan Yu Jian Peng Wei Zhang Jianlian Huang Zhixin Liang Junling Wang Zeyu Lin shiyun Xiong Jiazhao Wang Shaoming Huang Guangzhou Key Laboratory of Low‑Dimensional Materials and Energy Storage Devices School of Materials and EnergyGuangdong University of TechnologyGuangzhou 510006People’s Republic of China College of Materials and Chemistry China Jiliang UniversityHangzhou 310018People’s Republic of China Institute for Superconducting and Electronic Materials Australian Institute for Innovative MaterialsUniversity of WollongongInnovation CampusSquires WayNorth WollongongNSW 2522Australia

Metal tellurides(MTes) are highly attractive as promising anodes for high-performance potassium-ion batteries. The capacity attenuation of most reported MTe anodes is attributed to their poor electrical conductivity and large volume variation. The evolution mechanisms, dissolution properties, and corresponding manipulation strategies of intermediates(K-polytellurides, K-pTe_(x)) are rarely mentioned. Herein,we propose a novel structural engineering strategy to confine ultrafine CoTe_(2) nanodots in hierarchical nanogrid-in-nanofiber carbon substrates(CoTe_(2)@NC@NSPCNFs) for smooth immobilization of K-pTe_(x) and highly reversible conversion of CoTe_(2) by manipulating the intense electrochemical reaction process. Various in situ/ex situ techniques and density functional theory calculations have been performed to clarify the formation, transformation, and dissolution of K-pTe_(x)(K_(5)Te_(3) and K_(2)Te), as well as verifying the robust physical barrier and the strong chemisorption of K_(5)Te_(3) and K_(2)Te on S, N co-doped dual-type carbon substrates. Additionally, the hierarchical nanogrid-in-nanofiber nanostructure increases the chemical anchoring sites for K-pTe_(x), provides sufficient volume buffer space, and constructs highly interconnected conductive microcircuits, further propelling the battery reaction to new heights(3500 cycles at 2.0 A g^(-1)). Furthermore, the full cells further demonstrate the potential for practical applications. This work provides new insights into manipulating K-pTe_(x) in the design of ultralong-cycling MTe anodes for advanced PIBs.

关键词： Polytelluride dissolution Nanogrid-in-nanofiber structure Physicochemical adsorption Reaction mechanism Ultralonglife potassium storage

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Systematic Risk Analysis of Listed Financial Institutions from the Perspective of Complex Network

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Proceedings of Business and Economic Studies 2024年第1期7卷 104-110页

作者： shiyun Li School of Finance Nanjing University of Finance and EconomicsNanjing 210023Jiangsu ProvinceChina

Based on the complex network theory,this paper studies the systemic financial risks in China’s financial market.According to the industry classification of the China Securities Regulatory Commission in 2012,the daily closing prices of 45 listed financial institutions are collected and the daily return rates of each financial institution are measured according to the logarithmic return rate calculation formula.In this paper,the risk spillover value ΔCoVaR is used to measure the contribution degree of each financial institution to systemic risk.Finally,the relationship between the risk spillover valueΔCoVaR and the node topology index of the risk transmission network is investigated by using a regression model,and some policy suggestions are put forward based on the regression results.

关键词： Complex network Systemic risk GARCH model

Pathological progression of osteoarthritis:a perspective on subchondral bone

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Frontiers of Medicine 2024年第2期18卷 237-257页

作者： Xuefei Li Wenhua Chen Dan Liu Pinghua Chen shiyun Wang Fangfang Li Qian Chen Shunyi Lv Fangyu Li Chen Chen Suxia Guo Weina Yuan Pan Li Zhijun Hu Longhua Hospital Affiliated to Shanghai University of Traditional Chinese Medicine Shanghai200032China Research and Development Center of Chinese Medicine Resources and Biotechnology Shanghai University of Traditional Chinese MedicineShanghai201203China

Osteoarthritis(OA)is a degenerative bone disease associated with aging.The rising global aging population has led to a surge in OA cases,thereby imposing a significant socioeconomic burden.Researchers have been keenly investigating the mechanisms underlying OA.Previous studies have suggested that the disease starts with synovial inflammation and hyperplasia,advancing toward cartilage degradation.Ultimately,subchondral-bone collapse,sclerosis,and osteophyte formation occur.This progression is deemed as“top to bottom.”However,recent research is challenging this perspective by indicating that initial changes occur in subchondral bone,precipitating cartilage breakdown.In this review,we elucidate the epidemiology of OA and present an in-depth overview of the subchondral bone’s physiological state,functions,and the varied pathological shifts during OA progression.We also introduce the role of multifunctional signal pathways(including osteoprotegerin(OPG)/receptor activator of nuclear factor-kappa B ligand(RANKL)/receptor activator of nuclear factor-kappa B(RANK),and chemokine(CXC motif)ligand 12(CXCL12)/CXC motif chemokine receptor 4(CXCR4))in the pathology of subchondral bone and their role in the“bottom-up”progression of OA.Using vivid pattern maps and clinical images,this review highlights the crucial role of subchondral bone in driving OA progression,illuminating its interplay with the condition.

关键词： osteoarthritis subchondral bone OPG/RANKL/RANK CXCL12/CXCR4

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转型中的英国继续教育:弥合技能鸿沟

比较教育研究 2024年第1期46卷 80-89页

作者：王世赟北京师范大学国际与比较教育研究院北京100875

劳动者技能水平对经济的可持续发展至关重要。英国技能体系基于规范资格框架,通过高等教育部门、继续教育部门与雇主的紧密合作,培养具有不同资格等级的技能人才。然而,继续教育部门长期以来面临着受忽视和边缘化的问题,这导致技能资格... 详细信息

劳动者技能水平对经济的可持续发展至关重要。英国技能体系基于规范资格框架,通过高等教育部门、继续教育部门与雇主的紧密合作,培养具有不同资格等级的技能人才。然而,继续教育部门长期以来面临着受忽视和边缘化的问题,这导致技能资格认证的两极分化和技能人才供给侧的失衡。为了解决技能短缺和技能差距问题,自2015年起,英国政府进行多次审查,并推出一系列关于继续教育与技能的政策和法律。这些政策法律旨在从三个方面提升劳动者技能水平:加强对继续教育部门的拨款力度,将雇主纳入技能体系的核心,以及建立终身技能学习体系。英国政府的总体政策目标是通过这些改革,提供稳定、连贯且高质量的继续教育体系,以实现劳动者技能的增长,有效弥合技能鸿沟,从而促进英国产业经济的发展和综合国力的增强。

关键词：继续教育技能鸿沟雇主主导终身学习

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Facile synthesis of magnetic covalent organic framework nanocomposites for the enrichment and quantification of trace organophosphorus pesticides in fruit juice

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Food Science and Human Wellness 2024年

作者： Quanbin Fu Xin Sun Lu Liu Hailong Jiang Geoffrey I.N.Waterhouse shiyun Ai Rusong Zhao School of Chemical Sciences The University of Auckland College of Chemistry and Material Science Shandong Agricultural University Qilu University of Technology (Shandong Academy of Sciences) Shandong Analysis and Test Center Key Laboratory for Applied Technology of Sophisticated Analytical Instruments of Shandong Province College of Food Science and Engineering Shandong Agricultural University

Organophosphorus pesticides (OPPs) in foods pose a serious threat to human health， motivating the development of novel analytical methods for their rapid detection and quantification. A magnetic covalent organic framework (M-COF) adsorbent for the magnetic solid-phase extraction (MSPE) of OPPs from foods was reported. M-COF was synthesized by the Schiff base condensation reaction of 1，3，5-tris (4-aminophenyl)benzene and 4，4-biphenyldicarboxaldehyde on the surface of amino-functionalized magnetic nanoparticles. Density–functional theory (DFT) calculations showed that adsorption of OPPs onto the surface of M-COF involved hydrophobic effects， Van der Waals interactions， π–π interactions， halogen-N bonding， and hydrogen bonding. Combined with gas chromatography–mass spectrometry (GC–MS) technology， the MSPE method features low limits of detection for OPPs (0.002–0.015 μg/L)， good reproducibility (1.45%–6.14%)， wide linear detection range (0.01–1 μg/L， R≥ 0.9935)， and satisfactory recoveries (87.3%–110.4%). The method was successfully applied for the trace analysis of OPPs in spiked fruit juices.

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Study on Temperature Disaster Indicators of Passion Fruit in Southwest Fujian, China

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Journal of Geoscience and Environment Protection 2024年第1期12卷 1-12页

作者： shiyun Mou Ping Shao Yuchen Shi Shujie Yuan Lixin Su Plateau Atmosphere and Environment Key Laboratory of Sichuan Province School of Atmospheric Sciences Chengdu University of Information Technology Chengdu China Airport Operation Management Committee of Korla Licheng Airport Korla China Jilin Institute of Meteorogical Sciences Changchun China Jilin Provincial Key Laboratory of Changbai Mountain Meteorology & Climate Change Changchun China

In China, meteorological forecasting relies on meteorological data obtained from regional and national stations. However, there were discrepancies between the data collected from the meteorological station at the passion fruit growing base and the data from regional and national stations. Consequently, the high and low temperature disaster indicators determined by the meteorological station at the passion fruit growing base cannot be applied to meteorological forecasting. To address this issue and facilitate the monitoring and early warning of high and low temperature disasters in passion fruit cultivation in Fujian, China, we used multi-source hourly temperature data (including the data from meteorological observation stations in passion fruit growing bases, the nearest regional stations, and national surface conventional meteorological observation stations) in three cities in southwestern Fujian (Longyan, Sanming, and Zhangzhou) spanning the years 2020 to 2022. By employing comprehensive statistical analysis methods (0.5 interval division and Cumulative frequency), we identified that passion fruit in southwestern Fujian was susceptible to high temperature disasters during the blooming-fruiting period, as well as low temperature disasters during the sprouting period. Consequently, we developed high and low temperature disaster indicators based on data from regional and national stations for different phenological periods of passion fruit in this region.

关键词： Passion Fruit High Temperature Disaster Indicator Low Temperature Disaster Indicator Disaster Frequency Disaster Degree