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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01期 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.

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Elimination Theory in Differential and Difference Algebra

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Journal of Systems Science & Complexity 2019年第1期32卷 287-316页

作者： LI Wei yuan chun-Ming KLMM Academy of Mathematics and Systems Science Chinese Academy of Sciences University of Chinese Academy of Sciences

Elimination theory is central in differential and difference algebra. The Wu-Ritt characteristic set method, the resultant and the Chow form are three fundamental tools in the elimination theory for algebraic differential or difference equations. In this paper, the authors mainly present a survey of the existing work on the theory of characteristic set methods for differential and difference systems,the theory of differential Chow forms, and the theory of sparse differential and difference resultants.

关键词： Differential Chow forms differential resultants sparse differential resultants Wu-Ritt characteristic sets

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NUMERICAL SIMULATION OF THREE-DIMENSIONAL TURBULENT FLOW NEAR BODY SURFACE WITH LONGITUDINAL VORTICES

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Journal of Hydrodynamics 1991年第1期3卷 26-36页

作者： gao, gao Zhao, Run-yuan Wuhan Inst of Water Transportation Engineering Wuhan China

A calculating model of generalized partially-parabolic approximation is adopted in the research of numerical simulation of 3-D turbulent flow near body surface with longitudinal vortices in this paper. An analytical solution for Poisson equation is presented to generate the 3-D body-fitted coordinate system. The finite analytic method, which introduces 'virtual' time variable, is used calculating examples. The partially-parabolic approximation is made in the transformed equations. Compared with that made in the physical domain, it allows the equations to retain more terms. In 'zero' equation turbulence model, longitudinal eddy-viscosity and transverse eddy-viscosity are determined by using empiric formulae appropriate to inner layer and outer layer respectively. Of three example calculations, the results of turbulent flow past a flat plate with longitudinal vortices are compared with that of available experimental data. The comparison is found to be satisfactory. The results of the others - turbulent flow along a long cylinder and that past an ellipsoid with longitudinal vortices, are qualitatively reasonable.

关键词： Computer Simulation Computers Applications Hydrodynamics Mathematical Models Mathematical Techniques Differential Equations

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Near-Infrared-Emissive Self-assembled Polymers via the Implementation of Molecular Tweezer/Guest Complexation on a Supramolecular Coordination Complex Platform

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Chinese Journal of Polymer Science 2018年第3期36卷 399-405页

作者： Zong-chun gao Cheng-Peng Wei Yi-Fei Han Ming yuan Xu-Zhou Yan Feng Wang Chinese Academy of Sciences Key Laboratory of Soft Matter Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026 China Department of Chemical Engineering Stanford UniversityCalifornia 94305United States Faculty of Pharmaceutical Engineering Bengbu Medical CollegeAnhui Engineering Technology Research Center of Biochemical PharmaceuticalsBengbu 233030china

Coordination-driven self-assembly strategy has demonstrated the efficiency and versatility to construct well-ordered supramolecular coordination complexes （SCCs） such as discrete metallacycles and metallacages. In recent years, it has aroused tremendous interest to build more complexed self-assembled structures via the implementation of additional non-covalent recognition motifs on the SCCs platform. In this work, we have successfully attained this objective, with the elaborate manipulation of non-interfering pyridine-Pt2＋ and molecular tweezer/guest complexation in a hierarchical self-assembly manner. The resulting SCCs-based linear supramolecular polymers exhibit intriguing NIR-emissive behaviors, primarily attributed to the presence of intermolecular Pt（II）-Pt（II） metal-metal interactions in the non-covalent tweezering structure. Hence, supramolecular engineering of multiple non-covalent interactions offers a feasible avenue toward functional materials with tailored properties.

关键词： Supramolecular chemistry Metal-Ligand coordination Molecular tweezer Pt(II)-Pt(II) interactions Near-Infrared-Emission

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城市交通拥堵预测研究：以西安市为例

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计算机工程与应用 2025年第1期61卷 330-340页

作者：颜建强张霖高原李银香西北大学信息科学与技术学院西北大学经济管理学院

随着经济的发展和生活水平的提升，出行旅游逐渐成为流行的休闲方式，尤其在国庆等假日期间。然而，集中的出行需求引起的城市交通拥堵问题，不仅影响出行效率和体验，也加大了城市运行压力。该研究以西安市为例，深入分析假日期间的交... 详细信息

随着经济的发展和生活水平的提升，出行旅游逐渐成为流行的休闲方式，尤其在国庆等假日期间。然而，集中的出行需求引起的城市交通拥堵问题，不仅影响出行效率和体验，也加大了城市运行压力。该研究以西安市为例，深入分析假日期间的交通拥堵模式和特征，提出了一种基于深度学习拥堵预测模型ConstFormer。该模型融合了图卷积网络（graph convolutional network）和Transformer架构，利用图卷积网络探索空间邻接关系，以及Transformer的自注意力机制来挖掘长时空依赖关系，从而有效预测未来的交通状况。对比实验表明，ConstFormer模型对比基线模型均取得了最佳的性能，能够为人们规避高峰期和合理安排出行提供帮助。

关键词：拥堵预测数据分析城市交通图卷积网络 Transformer

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Continuous Subsonic-Sonic Flows in a Convergent Nozzle

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Acta Mathematica Sinica,English Series 2018年第4期34卷 749-772页

作者： yuan yuan NIE chun Peng WANG School of Mathematics Jilin University

This paper concerns continuous subsonic-sonic potential flows in a two-dimensional conver- gent nozzle. It is shown that for a given nozzle which is a perturbation of a straight one, a given point on its wall where the curvature is zero, and a given inlet which is a perturbation of an arc centered at the vertex, there exists uniquely a continuous subsonic-sonic flow whose velocity vector is along the normal direction at the inlet and the sonic curve, which satisfies the slip conditions on the nozzle walls and whose sonic curve intersects the upper wall at the given point. Furthermore, the sonic curve of this flow is a free boundary, where the flow is singular in the sense that the speed is only C1/2 H6lder continuous and the acceleration blows up. The perturbation problem is solved in the potential plane, where the flow is governed by a free boundary problem of a degenerate elliptic equation with two free boundaries and two nonlocal boundary conditions, and the equation is degenerate at one free boundary.

关键词： Continuous subsonic-sonic flow free boundary nonlocal boundary condition degeneracy,singularity

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Abrupt Flood–Drought Alternation in Southern China during Summer 2019

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Journal of Meteorological Research 2021年第6期35卷 998-1011页

作者： yuan yuan Hui gao Ting DING National Climate Center China Meteorological AdministrationBeijing 100081

We investigated the abrupt alternation from flood to drought in southern China during summer 2019 using multiple *** anomalies of precipitation occurred in southern China in the summer of 2019 and the daily precipitation in the south of the middle and lower reaches of the Yangtze River valley showed an abrupt change from flood to drought conditions around *** highest precipitation in 39 yr was recorded between 1 June and 14 July *** circulation systems affecting this high precipitation included a persistent deepened East Asian trough,the southward location of the western Pacific subtropical high,an intensified East Asian subtropical jet,an anomalous low-level cyclone from southern Japan to southern China,and extremely strong positive vorticity over the Jiangnan *** different atmospheric circulation anomalies from 15 July to 31 August caused continuously high temperatures,below-normal precipitation,and severe drought in Jiangnan *** investigations showed that the sudden change in atmospheric circulation around mid-July started in the mid and lower troposphere and was influenced by the northward track of Tropical Cyclone Danas in the northwestern Pacific.

关键词： abrupt changes summer precipitation East Asian trough western Pacific subtropical high tropical cyclone

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Changes in the Boreal Summer Intraseasonal Oscillation under Global Warming in CMIP6 Models

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Advances in Atmospheric Sciences 2024年第10期41卷 1984-1998页

作者： Zhefan gao Chaoxia yuan Key Laboratory of Meteorological Disaster of Ministry of Education Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersInstitute for Climate and Application Research(ICAR)Nanjing University of Information Science&TechnologyNanjing 210044China Application Laboratory Japan Agency of Marine-Earth Science and TechnologyYokohama 231-0017Japan

Changes in the activities of the Boreal Summer Intraseasonal Oscillation(BSISO)at the end of 21st century under the SSP5-8.5 scenario are assessed by adopting 17 CMIP6 models and the weak-temperature-gradient *** show that the intraseasonal variations become more *** BSISO-related precipitation anomaly shows a larger zonal scale and propagates further ***,there is no broad agreement among models on the changes in the eastward and northward propagation speeds and the frequency of individual *** the western North Pacific(WNP),the BSISO precipitation variance is significantly increased,at 4.62%K^(−1),due to the significantly increased efficiency of vertical moisture transport per unit of BSISO apparent *** vertical velocity variance is significantly decreased,at−3.51%K^(−1),in the middle troposphere,due to the significantly increased mean-state static *** in the lower-level zonal wind variance are relatively complex,with a significant increase stretching from the northwestern to southeastern WNP,but the opposite in other *** is probably due to the combined impacts of the northeastward shift of the BSISO signals and the reduced BSISO vertical velocity variance under global *** in strong and normal BSISO events in the WNP are also *** show same-signed changes in precipitation and large-scale circulation anomalies but opposite changes in the vertical velocity *** is probably because the precipitation anomaly of strong(normal)events changes at a rate much larger(smaller)than that of the meanstate static stability,causing enhanced(reduced)vertical motion.

关键词： Boreal Summer Intraseasonal Oscillation global warming CMIP6 weak-temperature-gradient assumption

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Inhibition of the cGAS–STING pathway:contributing to the treatment of cerebral ischemia-reperfusion injury

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Neural Regeneration Research 2025年第7期20卷 1900-1918页

作者： Hang Yang Yulei Xia Yue Ma Mingtong gao Shuai Hou Shanshan Xu Yanqiang Wang School of Clinical Medicine Shandong Second Medical UniversityWeifangShandong ProvinceChina Department of Emergency The Affiliated Hospital of Weifang Medical UniversityWeifangShandong ProvinceChina Department of Neurology Ⅱ The Affiliated Hospital of Weifang Medical UniversityWeifangShandong ProvinceChina

The cGAS–STING pathway plays an important role in ischemia-reperfusion injury in the heart,liver,brain,and kidney,but its role and mechanisms in cerebral ischemia-reperfusion injury have not been systematically ***,we outline the components of the cGAS–STING pathway and then analyze its role in autophagy,ferroptosis,cellular pyroptosis,disequilibrium of calcium homeostasis,inflammatory responses,disruption of the blood–brain barrier,microglia transformation,and complement system activation following cerebral ischemia-reperfusion *** further analyze the value of cGAS–STING pathway inhibitors in the treatment of cerebral ischemia-reperfusion injury and conclude that the pathway can regulate cerebral ischemia-reperfusion injury through multiple *** of the cGAS–STING pathway may be helpful in the treatment of cerebral ischemia-reperfusion injury.

关键词： calcium homeostasis cellular autophagy cerebral ischemia-reperfusion injury cGAS–STING pathway ferroptosis gut–brain–microbiota axis inflammatory light chain 3 microglial cells Syntaxin-17 protein

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New horizons for selenium in animal nutrition and functional foods

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Animal Nutrition 2022年第4期11卷 80-86页

作者： Xin Gu chun-qi gao Guangdong Provincial Key Laboratory of Animal Nutrition Control/Key Laboratory of Chicken Genetics Breeding and ReproductionMinistry of AgricultureCollege of Animal ScienceSouth China Agricultural University GuangdongChina College of Animal SciencesZhejiang UniversityHangzhouChina

Selenium(Se),one of the indispensable nutrients for both human health and animal growth,participates in various physiological functions,such as antioxidant and immune responses and *** role of dietary Se,in its organic and inorganic forms,has been well documented in domestic ***,many feeding strategies for different animals have been developed to increase the Se concentration in animal products to address Se deficiency and even as a potential nutritional strategy to treat free radical-associated ***,studies on investigating the optimum addition of Se in feed,the long-term consequences of Se usage in food for animal nutrition,the mechanism of metallic Se nanoparticle(SeNP)transformation in vivo,and the nutritional effects of SeNPs on feed workers and the environment are urgently *** from the absorption and metabolism mechanism of Se,this review discusses the antioxidant role of Se in *** on this characteristic,we further investigated the application of Se in animal health and described some unresolved issues and unanswered questions warranting further *** review is expected to provide a theoretical reference for improving the quality of food animal meat as well as for the development of Se-based biological nutrition enhancement technology.

关键词： Selenium Antioxidant Meat quality Functional foods

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