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Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第1期68卷 288-296页

作者： Shuai Liu Wen-Qiang Xu Ying-Tong Di Man-Cheng Tang Ding-Kang Chen Ming-Ming Cao Yao-Wen Chang Hong-Yu Tang Chun-Mao yuan Jun-Bo Yang Zhi-Li Zuo Han Guo Zi-Fei Xu Ying Zeng Yun-Dong wu Xiao-Jiang Hao Key Laboratory of Phytochemistry and Natural Medicines (Chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay Laboratory State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

关键词： metabolon Diels-Alder reaction semipinacol rearrangement biosynthesis notoamides spiro polycyclic alkaloids

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Approximation to the Distribution of the Least Squares Estimators in Two Dimensional Cosine Models by Randomly Weighted Bootstrap

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Acta Mathematicae Applicatae Sinica 2013年第4期29卷 765-776页

作者： yuan-yuan ZHAO Rui-xing MING Yao-hua wu Department of Statistics and Finance University of Science and Technology of China School of Mathematical Sciences Nanjing Normal University Institute of Finance and Statistics Nanjing Normal University School of Statistics and Mathematics Zhejiang Gongshang University

Recently, Kundu and Gupta （Metrika, 48：83 C 97, 1998） established the asymptotic normality of the least squares estimators in the two dimensional cosine model. In this paper, we give the approximation to the general least squares estimators by using random weights which is called the Bayesian bootstrap or the random weighting method by Rubin （Annals of Statistics, 9：130 C 134, 1981） and Zheng （Acta Math. Appl. Sinica （in Chinese）, 10（2）： 247 C 253, 1987）. A simulation study shows that this approximation works very well.

关键词： two dimensional model least squares estimator Bayesian bootstrap random weighting method

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Adaptive Tracking Control of Mobile Manipulators with Affine Constraints and Under-actuated Joints

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International Journal of Automation and computing 2018年第6期15卷 728-735页

作者： Wei Sun Wen-xing yuan Yu-Qiang wu School of Mathematics Science Liaocheng University Liaocheng 252000 China Institute of Automation Qufu Normal University Qufu 273165 China

Adaptive motion/force tracking control is considered for a class of mobile manipulators with affine constraints and under-actuated joints in the presence of uncertainties in this paper. Dynamic equation of mobile manipulator is transformed into a controllable form based on dynamic coupling technique. In view of the asymptotic tracking idea and adaptive theory, adaptive controllers are proposed to achieve the desired control objective. Detailed simulation results confirm the validity of the control strategy.

关键词： Tracking control affine constraints mobile manipulators under-actuated joints dynamic coupling

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滨水空间视觉特征的注意力和情绪效应——基于高校在校学生眼动追踪实验的证据

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中山大学学报（自然科学版）（中英文） 2025年第1期64卷 207-217页

作者：罗玮菁袁媛王琳婷吴丽娟中山大学地理科学与规划学院广东广州510006 广东省城市化与地理环境空间模拟重点实验室广东广州510006 广州市城市规划勘测设计研究院有限公司广东广州510060

随着社会竞争压力倍增以及城市生活高速运转,高校在校学生心理健康问题日益凸显。大量研究证实蓝绿空间具有多重健康效益。作为一种日常疗愈景观,蓝绿空间是促进心理健康的重要“自然处方”和环境资产。本研究基于视觉景观感知理论,采... 详细信息

随着社会竞争压力倍增以及城市生活高速运转,高校在校学生心理健康问题日益凸显。大量研究证实蓝绿空间具有多重健康效益。作为一种日常疗愈景观,蓝绿空间是促进心理健康的重要“自然处方”和环境资产。本研究基于视觉景观感知理论,采用虚拟现实眼动追踪实验,收集51名高校在校学生的眼动行为和情绪数据,探究滨水空间视觉特征对高校在校学生注意力分配和情绪反应的作用。结果显示:公共活动型水岸引起的注视行为和愉悦情绪显著更多,不同观赏视角之间滨水空间感知的瞳孔反应和愉悦情绪存在差异。不同水平植被密度、植被结构层次和水面可视度对注意力和情绪的影响存在显著差异,且在不同空间类型和观赏视角下显示出异质性特征,即滨水空间属性之间具有交互作用。研究有助于丰富蓝绿空间人地感知理论的实验性循证探索和差异化研究,结论可为人本尺度下滨水空间精细化场所营造提供参考,以期为我国青年友好滨水空间建设提供实证支撑。

关键词：滨水空间注意力情绪眼动实验青年友好

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Analysis of antibiotic resistance of Escherichia coli isolated from the Yitong River in North-east China

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Frontiers of Environmental Science & Engineering 2019年第3期13卷 127-135页

作者： Yangyang Yu Xiaolin Zhu Guanlan wu Chengzhi Wang xing yuan School of Environment Northeast Normal University Changchun 130117 China

The Yitong River is one of the largest secondary tributaries of the Songhua River. The area where the Yitong River flows is densely populated and contains the livestock and poultry breeding areas of northeast China. These areas introduce a high risk of antibiotic contamination. In this study, the concentrations of four types of typical antibiotics including quinolones, tetracyclines, sulfonamides, and trimethoprim were determined by solid phase extraction-high performance liquid chromatography. The antibiotic resistance of Escherichia coli caused by antibiotic pollution was investigated. The concentration of total coliforms in the Yitong River was detected by the plate counting method. The antibiotic resistance of E. coli to quinolones, tetracyclines, sulfonamides, and trimethoprim was analyzed by the Kirby-Bauer method. The results showed that the concentration of total coliforms in the summer was higher than that in the spring. There was a seasonal difference in the resistance rate of E. coli to antibiotics except trimethoprim. The antibiotic resistance to fluoroquinolones was relatively low. The resistance rate to tetracyclines was higher during the summer. Moreover, resistance to several antibiotics was observed in all sections. This study provides basic data for research on pollution characteristics and prevention of antibiotic exposure in rivers.

关键词： Yitong River Coliform bacteria Antibiotic resistance Escherichia coli

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Causes and Predictability of the 2021 Spring Southwestern China Severe Drought

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Advances in Atmospheric Sciences 2022年第10期39卷 1766-1776页

作者： Yunyun LIU Zeng-Zhen HU Renguang wu xing yuan CMA Climate Studies Key Laboratory National Climate CenterChina Meteorological AdministrationBeijing 100081China Key Laboratory of Meteorological Disaster Ministry of Education&Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science&TechnologyNanjing 210044China Climate Prediction Center NCEP/NOAACollege ParkMaryland 20740USA School of Earth Sciences Zhejiang UniversityHangzhou 310058China School of Hydrology and Water Resources Nanjing University of Information Science and TechnologyNanjing 210044China

In the spring of 2021,southwestern China(SWC)experienced extreme drought,accompanied by the highest seasonal-mean temperature record since *** drought event occurred in the decaying phase of a La Niña event with negative geopotential height anomalies over the Philippine Sea,which is distinct from the historical ***,spring drought over SWC is often linked to El Niño and strong western North Pacific subtropical ***,we show that the extreme drought in the spring of 2021 may be mainly driven by the atmospheric internal variability and amplified by the warming ***,the evaporation increase due to the high temperature accounts for about 30%of drought severity,with the contributions of its linear trend portion being nearly 20%and the interannual variability portion being about 10%.Since the sea surface temperature forcing from the tropical central and eastern Pacific played a minor role in the occurrence of drought,it is a challenge for a climate model to capture the 2021 SWC drought beyond one-month lead times.

关键词： extreme spring drought Southwestern China precipitation evaporation warming trend internal variability predictability

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Deep learning-based software engineering: progress,challenges, and opportunities

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Science China(Information Sciences) 2025年第1期68卷 57-144页

作者： Xiangping CHEN xing HU yuan HUANG He JIANG Weixing JI Yanjie JIANG Yanyan JIANG Bo LIU Hui LIU Xiaochen LI Xiaoli LIAN Guozhu MENG Xin PENG Hailong SUN Lin SHI Bo WANG Chong WANG Jiayi WANG Tiantian WANG Jifeng XUAN Xin XIA Yibiao YANG Yixin YANG Li ZHANG Yuming ZHOU Lu ZHANG School of Journalism and Communication Sun Yat-sen University School of Software Technology Zhejiang University School of Software Engineering Sun Yat-sen University School of Software Dalian University of Technology School of Computer Science and Technology Beijing Institute of Technology Key Laboratory of High Confidence Software Technologies (Peking University) Ministry of EducationSchool of Computer Science Peking University State Key Laboratory for Novel Software Technology Nanjing University School of Computer Science and Engineering Beihang University Institute of Information Engineering Chinese Academy of Sciences School of Computer Science Fudan University State Key Laboratory of Complex & Critical Software Environment (CCSE) School of Software Beihang University School of Computer and Information Technology Beijing Jiaotong University School of Computer Science and Technology Harbin Institute of Technology School of Computer Science Wuhan University Huawei Technologies

Researchers have recently achieved significant advances in deep learning techniques, which in turn has substantially advanced other research disciplines, such as natural language processing, image processing, speech recognition, and software engineering. Various deep learning techniques have been successfully employed to facilitate software engineering tasks, including code generation, software refactoring, and fault localization. Many studies have also been presented in top conferences and journals, demonstrating the applications of deep learning techniques in resolving various software engineering tasks. However,although several surveys have provided overall pictures of the application of deep learning techniques in software engineering,they focus more on learning techniques, that is, what kind of deep learning techniques are employed and how deep models are trained or fine-tuned for software engineering tasks. We still lack surveys explaining the advances of subareas in software engineering driven by deep learning techniques, as well as challenges and opportunities in each subarea. To this end, in this study, we present the first task-oriented survey on deep learning-based software engineering. It covers twelve major software engineering subareas significantly impacted by deep learning techniques. Such subareas spread out through the whole lifecycle of software development and maintenance, including requirements engineering, software development, testing, maintenance, and developer collaboration. As we believe that deep learning may provide an opportunity to revolutionize the whole discipline of software engineering, providing one survey covering as many subareas as possible in software engineering can help future research push forward the frontier of deep learning-based software engineering more systematically. For each of the selected subareas,we highlight the major advances achieved by applying deep learning techniques with pointers to the available datasets i

关键词： deep learning software engineering software benchmark software artifact representation survey

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Super tensile ductility in an as-cast TiVNbTa refractory high-entropy alloy

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Progress in Natural Science:Materials International 2024年第5期34卷 1076-1084页

作者： Chao Guo yuan xing Pan wu Ruitao Qu Kexing Song Feng Liu State Key Laboratory of Solidification Processing School of Materials Science and Engineering Northwestern Polytechnical University Institute of Materials Henan Academy of Sciences

Refractory high-entropy alloy(RHEA) usually exhibits a high melting point and hence a very high deformation resistance at high temperatures. However, the relatively poor plasticity at room temperature, i.e., only few RHEAs displaying as-cast tensile ductility, strongly limits the applications of RHEAs as engineering materials. In this work, we show a huge tensile ductility observed in an as-cast TiVNbTa RHEA(～40 % fracture elongation)accompanying with a high yield strength(～800 MPa), which are rarely reported properties for RHEAs. The ascast alloy shows a simple body-centered cubic(BCC) structure with dendrites. Ductile fracture with many dimples is the main fracture mechanism, while no twinning and deformation induced phase transition was observed. The uniform plastic deformation mainly relies on the planar and cross-slip of dislocations. The present result suggests the huge ductility potentials for RHEAs, providing a clue for designs future high performance RHEAs with good ductility.

关键词： Deformation mechanism Fracture mechanism Mechanical properties Refractory high-entropy alloy

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Study on the performance of TEG with heat transfer enhancement using graphene-water nanofluid for a TEG cooling system

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Science China(Technological Sciences) 2017年第8期60卷 1168-1174页

作者： LI YiHuai wu ZiHua XIE HuaQing xing JiaoJiao MAO JianHui WANG yuan yuan LI Zhen School of Environmental and Materials Engineering College of EngineeringShanghai Polytechnic University School of Environmental and Chemical Engineering Shanghai University

Improvement of the heat transfer effect of cold side of a thermoelectric generator(TEG) is one of the approaches to enhance the performance of the TEG *** a new type of heat transfer media,nanofluids can enhance the heat transfer performance of working liquid *** this study,the performance of a commercial TEG with graphene-water(GW) nanofluid as coolants in a minichannel heat exchanger is investigated experimentally at low *** results show that the output power of TEG increases with the flow rate under 950 mL/***,the fluid flow rate has no influence on the output power of TEG with higher flow rate(larger than 950 mL/min) when the heat transfer dynamic balance state of the system is *** optimal concentration and flow rate of nanofluid are 0.1 wt%and 950 mL/min,*** the optimal conditions,the improved voltage,output power and conversion efficiency with GW nanofluid applied in the cooling system are increased by11.29%,21.55%and 3.5%in comparison with those with only water applied,respectively.

关键词： thermoelectric generation graphene-water nanofluid power generation

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Advances and applications in single-cell and spatial genomics

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Science China Life Sciences 2025年

作者： Jingjing Wang Fang Ye Haoxi Chai Yujia Jiang Teng Wang Xia Ran Qimin Xia Ziye Xu Yuting Fu Guodong Zhang Hanyu wu Guoji Guo Hongshan Guo Yijun Ruan Yongcheng Wang Dong xing Xun Xu Zemin Zhang Beijing Advanced Innovation Center for Genomics (ICG) Peking University Guangdong Provincial Key Laboratory of Genome Read and Write BGI Research Bone Marrow Transplantation Center of the First Affiliated Hospital & Liangzhu Laboratory Zhejiang University School of Medicine Life Sciences Institute and The Second Affiliated Hospital Zhejiang University BGI Research Biomedical Pioneering Innovation Center (BIOPIC) and School of Life Sciences Peking University Academy for Advanced Interdisciplinary Studies Peking University Institute of Hematology Zhejiang University Department of Laboratory Medicine of The First Affiliated Hospital & Liangzhu Laboratory Zhejiang University School of Medicine Center for Stem Cell and Regenerative Medicine Zhejiang University School of Medicine Zhejiang Provincial Key Lab for Tissue Engineering and Regenerative Medicine Dr.Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine

The applications of single-cell and spatial technologies in recent times have revolutionized the present understanding of cellular states and the cellular heterogeneity inherent in complex biological systems. These advancements offer unprecedented resolution in the examination of the functional genomics of individual cells and their spatial context within tissues. In this review, we have comprehensively discussed the historical development and recent progress in the field of single-cell and spatial genomics. We have reviewed the breakthroughs in single-cell multi-omics technologies, spatial genomics methods, and the computational strategies employed toward the analyses of singlecell atlas data. Furthermore, we have highlighted the advances made in constructing cellular atlases and their clinical applications,particularly in the context of disease. Finally, we have discussed the emerging trends, challenges, and opportunities in this rapidly evolving field.

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