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Inexact proximal gradient algorithm with random reshuffling for nonsmooth optimization

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Science China(Information Sciences) 2025年第1期68卷 219-237页

作者： xia JIANG Yanyan FANG xianlin ZENG Jian SUN Jie CHEN National Key Lab of Autonomous Intelligent Unmanned Systems School of AutomationBeijing Institute of Technology Beijing Institute of Technology Chongqing Innovation Center School of Electronic and Information Engineering Tongji University

Proximal gradient algorithms are popularly implemented to achieve convex optimization with nonsmooth regularization. Obtaining the exact solution of the proximal operator for nonsmooth regularization is challenging because errors exist in the computation of the gradient; consequently, the design and application of inexact proximal gradient algorithms have attracted considerable attention from researchers. This paper proposes computationally efficient basic and inexact proximal gradient descent algorithms with random reshuffling. The proposed stochastic algorithms take randomly reshuffled data to perform successive gradient descents and implement only one proximal operator after all data pass through. We prove the convergence results of the proposed proximal gradient algorithms under the sampling-without-replacement reshuffling *** computational errors exist in gradients and proximal operations, the proposed inexact proximal gradient algorithms can converge to an optimal solution neighborhood. Finally, we apply the proposed algorithms to compressed sensing and compare their efficiency with some popular algorithms.

关键词： proximal operator random reshuffling inexact computation compressed sensing nonsmooth optimization

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乌伦古湖全新世气候变化的环境磁学记录

第四纪研究 2012年第4期32卷 803-811页

作者：刘宇航夏敦胜周爱锋张俊辉赵家驹张英兰州大学西部环境与气候变化研究院西部环境教育部重点实验室兰州730000 中国科学院寒区旱区环境科学与工程研究所沙漠与沙漠化重点实验室兰州730000

对位于新疆北部阿勒泰地区福海县的乌伦古湖WLG10C孔岩芯进行了环境磁学分析,以平行孔(WLG10B)AMS^(14)C测年为年代框架,重建了该地区全新世以来气候环境变化。结果显示:1)乌伦古湖磁性矿物以细颗粒亚铁磁性矿物为主,并含有少量不完整... 详细信息

对位于新疆北部阿勒泰地区福海县的乌伦古湖WLG10C孔岩芯进行了环境磁学分析,以平行孔(WLG10B)AMS^(14)C测年为年代框架,重建了该地区全新世以来气候环境变化。结果显示:1)乌伦古湖磁性矿物以细颗粒亚铁磁性矿物为主,并含有少量不完整反铁磁性矿物和富铁绿泥石类粘土顺磁性矿物,磁学参数x_(ARM)和x_(ARM)/x可用作气候变化代用指标,记录了研究区气候环境变化;2)研究区在全新世早期(***.P.以前)为冷干气候,中、晚全新世(***.P.以来)为暖湿气候。在***.P.左右为该湖高湖面时期,在3500～***.P.之间存在与全球范围一致的突发冷事件。乌伦古湖全新世气候变化与周边环境记录较一致,气候变化模式符合中亚干旱区全新世气候变化西风模式。

关键词：乌伦古湖西风模式环境磁学全新世

川西高原黄土—古土壤序列环境磁学研究最新进展与展望

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山地学报 2021年第6期39卷 806-820页

作者：陈梓炫杨军怀王树源吕镔杨胜利夏敦胜兰州大学资源环境学院兰州730000 福建师范大学地理科学学院福州350007

川西高原堆积的黄土—古土壤序列是青藏高原东部地区良好的古气候记录载体,记录了不同时间尺度的古环境变化,对揭示印度季风和高原季风的演化历史及其驱动机制,理解青藏高原隆升效应与周边大气环流之间的关系具有重要意义。相比黄土高原... 详细信息

川西高原堆积的黄土—古土壤序列是青藏高原东部地区良好的古气候记录载体,记录了不同时间尺度的古环境变化,对揭示印度季风和高原季风的演化历史及其驱动机制,理解青藏高原隆升效应与周边大气环流之间的关系具有重要意义。相比黄土高原,川西高原黄土环境磁学研究相对薄弱,亟需厘清黄土的磁学性质、磁化率增强机制、成壤过程中磁性矿物的生成、转化机制及其与环境因子之间的响应关系,明确磁学参数的环境意义。本文全面评述了川西黄土环境磁学进展,回顾和总结川西高原黄土的磁性矿物的类型、浓度、粒径等磁学特征及其影响因素和磁学参数的古环境意义,并对存在的问题进行讨论,以期推动青藏高原东部黄土的环境磁学研究及其在古环境和古气候中的应用。

关键词：青藏高原东部川西高原黄土环境磁学古环境意义

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中亚地区现代表土磁学特征及其古环境意义

第四纪研究 2006年第6期26卷 937-946页

作者：夏敦胜魏海涛马剑英王训明张家武赵晖中国科学院寒区旱区环境与工程研究所沙漠与沙漠化重点实验室兰州730000 兰州大学资源环境学院西部环境教育部重点实验室中德干旱环境联合研究中心兰州730000

在中国西北地区主要沙漠、绿洲和戈壁及蒙古国南部戈壁等亚洲中部粉尘源区采集了表土(包括沙漠和土壤)样品,系统分析了样品的磁学性质(包括磁化率、无磁滞磁化率、等温剩磁、磁滞回线和热磁曲线)。结果表明,中亚地区表土样品中主要磁性... 详细信息

在中国西北地区主要沙漠、绿洲和戈壁及蒙古国南部戈壁等亚洲中部粉尘源区采集了表土(包括沙漠和土壤)样品,系统分析了样品的磁学性质(包括磁化率、无磁滞磁化率、等温剩磁、磁滞回线和热磁曲线)。结果表明,中亚地区表土样品中主要磁性矿物是铁磁矿,含有赤铁矿和磁赤铁矿,并伴有少量顺磁性矿物;磁性矿物粒度主要是准单畴(PSD)和多畴(MD),超顺磁性颗粒含量较低,接近于中国西部黄土地层含量。中亚地区表土磁性矿物含量总体都较低,磁性矿物含量在空间上与降雨量成正比。研究结果指示西部地区(准噶尔盆地和南部塔里木盆地)表土样品较北部地区(鄂尔多斯高原、阿拉善高原以及蒙古高原)表土样品,其粗颗粒磁性矿物含量高,而细颗粒磁性矿物含量低。本研究结果为黄土地层古土壤磁性增强源自成土过程提供了最直接的证据。

关键词：环境磁学表土黄土沙漠戈壁中亚地区

Potential dependence in electrocatalysis:a theoretical perspective

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Science China Chemistry 2025年第1期68卷 21-25页

作者： Leyu Liu Zhaoming xia Zeyu Wang Yinjuan Chen Hai xiao Department of Chemistry Tsinghua UniversityBeijing 100084China Fundamental Science Center of Rare Earths Ganjiang Innovation AcademyChinese Academy of SciencesGanzhou 341119China Key Laboratory of Advanced Catalytic Materials and Technology Advanced Catalysis and Green Manufacturing Collaborative Innovation CenterChangzhou UniversityChangzhou 213164China

Electrocatalysis is a key technology for the new energy era and sustainable development,serving as the interface for interconversion of electrical and chemical energies,which spans a wide spectrum of applications in sustainable energy and environmental *** reactions including electrochemical CO_(2)reduction reaction(eCO_(2)RR),hydrogen evolution reaction(HER),and oxygen evolution/reduction reactions(OER/ORR),hold essential promise for renewable energy technologies as well as complement the biogeochemical carbon and oxygen cycles.

关键词： spectrum interface Electrocatalysis

3500年来祁连山中段天鹅湖岩芯记录的沉积环境变化

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沉积学报 2018年第3期36卷 521-530页

作者：闫天龙王振亭贺建桥黄小忠夏敦胜王宗礼兰州大学资源环境学院西部环境教育部重点实验室兰州730000 中国科学院西北生态环境资源研究院兰州730000

湖泊沉积,特别是内陆高山封闭湖泊沉积是古气候研究的重要载体,可以高分辨率、敏感地记录连续的古气候环境变化。选取祁连山中段天鹅湖沉积岩芯TEB孔的10个陆生植物残体进行AMS^(14)C测年并建立年代框架,结合对总有机碳(TOC)含量、矿物... 详细信息

湖泊沉积,特别是内陆高山封闭湖泊沉积是古气候研究的重要载体,可以高分辨率、敏感地记录连续的古气候环境变化。选取祁连山中段天鹅湖沉积岩芯TEB孔的10个陆生植物残体进行AMS^(14)C测年并建立年代框架,结合对总有机碳(TOC)含量、矿物成分及元素相对含量等指标的分析结果,重建了天鹅湖3 500年来的沉积环境变化特征。初步研究结果表明:碳酸盐含量变化主要受控于地下水补给量的变化,进而反映区域降水量,1 534 BC^1 300 AD期间,天鹅湖区降水呈减少的趋势,尤其是中世纪暖期(720~1 300 AD),是3 500年来最干旱的时期;小冰期开始于1 300 AD,共出现三次降水较多的时期,1 600~1 730AD为小冰期最盛期。受西风环流影响,天鹅湖沉积记录了该区域中世纪暖期相对暖干,而小冰期较为冷湿的变化特征。同时,该湖记录的小冰期气候相比于中世纪暖期更不稳定。

关键词：祁连山天鹅湖晚全新世环境变化中世纪暖期小冰期

Phosphorylation modification reverses the transcriptional inhibitory activity of CsMYB4a in tea plants(Camellia sinensis)

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Horticultural Plant Journal 2025年第1期11卷 406-416页

作者： Guoliang Ma Yunyun Han Tongtong Li Tao xia Liping Gao School of Life Science Anhui Agricultural UniversityHefeiAnhui 230036China State Key Laboratory of Tea Plant Biology and Utilization Key Laboratory of Tea Biology and Tea Processing of Ministry of AgricultureAnhui Provincial Laboratory of Tea Plant Biology and UtilizationAnhui Agricultural UniversityHefeiAnhui 230036China

The members of the fourth subgroup of R2R3-MYB(Sg4 members)are well-known inhibitors of phenylpropanoid and lignin synthesis *** C2 domain is closely related to the transcriptional inhibitory activity of Sg4 *** modification enhances the transcriptional inhibitory activity of Sg4 ***,we identified a phosphorylation site on the C2 domain of Cs MYB4a from tea plants(Camellia sinensis).A mitogen-activated protein kinase(MAPK),named Cs MPK3-2,phosphorylated this site on the C2 domain of Cs *** experiments revealed that phosphorylation of Cs MYB4a weakened its ability to inhibit the gene expression of PAL,C4H,and 4CL in the phenylpropanoid pathway and activated the expression of transcription factor YABBY5,maintaining the adaxial-abaxial polarity of the *** out Nt YAB5 in Cs MYB4a transgenic tobacco partially repaired the leaf wrinkling phenotype caused by Cs *** C1 domain exhibited an activation function when the C2 domain of Cs MYB4a was phosphorylated by Cs MPK3-2,causing this reversal *** results enrich our understanding of the regulatory diversity of Sg4 members.

关键词： Camellia sinensis Cs MYB4a Phenylpropanoid pathway MAPK YABBY Leaf development

Metagenomic perspectives on antibiotic resistance genes in tap water:The environmental characteristic,potential mobility and health threat

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Journal of Environmental Sciences 2025年第1期147卷 582-596页

作者： Qiyue Meng Yibo Zhang Da He Yu xia Jie Fu Chenyuan Dang School of Environmental Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China Key Laboratory of Ecological Impacts of Hydraulic Projects and Restoration of Aquatic Ecosystem of Ministry of Water Resources Institute of HydroecologyMinistry of Water Resources&Chinese Academy of SciencesWuhan 430074China School of Environmental Science and Engineering College of EngineeringSouthern University of Science and TechnologyShenzhen 518055China

As an emerging environmental contaminant,antibiotic resistance genes(ARGs)in tap water have attracted great *** studies have provided ARG profiles in tap water,research on their abundance levels,composition characteristics,and potential threat is still ***,9 household tap water samples were collected from the Guangdong-Hong Kong-Macao Greater Bay Area(GBA)in ***,75 sets of environmental sample data(9 types)were downloaded from the public *** was then performed to explore the differences in the abundance and composition of ARGs.221 ARG subtypes consisting of 17 types were detected in tap *** the ARG abundance in tap water was not significantly different from that found in drinking water plants and reservoirs,their composition *** tap water samples,the three most abundant classes of resistance genes were multidrug,fosfomycin and MLS(macrolide-lincosamidestreptogramin)ARGs,and their corresponding subtypes ompR,fosX and macB were also the most abundant ARG *** the potential mobility,vanS had the highest abundance on plasmids and viruses,but the absence of key genes rendered resistance to vancomycin ***,the majority of ARGs present in tap water were those that have not been assessed and are currently not listed as high-threat level ARG families based on the World Health Organization *** the current potential threat to human health posed by ARGs in tap water is limited,with persistent transfer and accumulation,especially in pathogens,the potential danger to human health posed by ARGs should not be ignored.

关键词： Antibiotic resistance genes Tap water Plasmids Viruses Health threat

Associations between food insecurity with gestational diabetes mellitus and maternal outcomes mediated by dietary diversity:A cross-sectional study

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World Journal of Diabetes 2025年第2期16卷 92-102页

作者： Hong-Li Hou Gui-xia Sun Department of Gynecology and Obstetrics Children’s Hospital of ShanxiWomen Health Center of ShanxiTaiyuan 030001Shanxi ProvinceChina

BACKGROUND Food insecurity(FI)during pregnancy negatively impacts maternal health and raises the risk of gestational diabetes mellitus(GDM)and pregnancy-induced hypertension(PIH),resulting in adverse outcomes for both mother and *** To investigate the relationships between FI and pregnancy outcomes,particularly GDM and PIH,while also examining the mediating role of the dietary diversity score(DDS).METHODS A cross-sectional study was undertaken to examine this relationship,involving 600 pregnant *** were women aged 18 years or older who provided complete data on FI and pregnancy *** FI was measured via the Household Food Security Survey Module,with GDM defined as fasting plasma glucose levels of≥5.1 mmol/L or a 2-hour oral glucose tolerance test value of≥8.5 mmol/*** DDS is determined by evaluating one's food consumption based on nine distinct food groups.A logistic regression model was used to explore the relationship between FI and PIH,and *** Seventeen percent of participants reported experiencing FI during *** study found a significant association between FI and an elevated risk of GDM[odds ratio(OR)=3.32,95%CI:1.2-5.4].Once more,food-insecure pregnant women had higher rates of PIH(OR=0.10,95%CI:0.02-0.45)and they also faced a higher likelihood of neonatal complications,such as neonatal intensive care unit’s admissions and the birth of infants with extremely low birth *** FI wasfurther linked to metabolic disruptions,such as elevated fasting blood sugar(FBS),low-density lipoprotein cholesterol,and triglyceride *** results indicate that the DDS acts as a significant mediator in the relationship between FI and the incidence of *** particular,the mediation analysis showed that approximately 65%of the effect was mediated through DDS(P=0.002).CONCLUSION These findings underscore the serious challenges that FI presents during pregnancy and its effects on maternal and infant ***,the study

关键词： Food insecurity Gestational diabetes mellitus Gestational hypertension Pregnancy Maternal health Infant health Dietary diversity score