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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 BotanyChinese Academy of SciencesKunming 650201China Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical OncogenomicsPeking University Shenzhen Graduate SchoolShenzhen 518055China Shenzhen Bay Laboratory Shenzhen 518055China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Microbial Metabolism School of Life Sciences&BiotechnologyShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical UniversityGuiyang 550014China Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest ChinaKunming Institute of BotanyChinese Academy of SciencesKunming 650201China Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical SciencesBeijing 100730China

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 *** 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 ***,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol *** 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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移动数据库中企业信息质量优化选择研究

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计算机仿真 2018年第2期35卷 380-383页

作者：文明瑶华南农业大学珠江学院广东广州510900

对移动数据库中企业信息质量的优化选择,能够有效提高数据信息的质量。对信息质量的选择,需要把信息信号的解析模型进行分解,将信息节点选择数据发送至数据节点。传统方法简化数据参量间相关的关系,构建异常的选择体系,但忽略了信息节... 详细信息

对移动数据库中企业信息质量的优化选择,能够有效提高数据信息的质量。对信息质量的选择,需要把信息信号的解析模型进行分解,将信息节点选择数据发送至数据节点。传统方法简化数据参量间相关的关系,构建异常的选择体系,但忽略了信息节点的传送处理,导致选择精度偏低。提出基于分布式离群的移动数据库的信息质量优化选择方法。该方法首先对数据库中的信息质量进行特征提取,建立数据信息网络模型,利用固有的模态分解把信息信号的解析模型进行分解,利用分布式离群的选择算法对提取的数据特征进行数据优化选择,将信息节点利用滑动的窗口选择数据发送至数据节点,选择数据节点间的离群数据和数据节点,最后将数据节点选择传送的离群数据得出优化后的数据,由此完成对移动数据库的信息质量优化选择。实验结果表明,所提方法能有效地提高数据优化选择的准确率。

关键词：移动数据库信息质量优化选择

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Flotation separation of chalcopyrite from pyrite using mineral fulvic acid as selective depressant under weakly alkaline conditions

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中国有色金属学报 2025年第1期35卷 313-325页

作者： Zhi-hao SHEN Shu-ming wen Jia-mei HAO Qi-cheng FENG State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Faculty of Land Resource EngineeringKunming University of Science and TechnologyKunming 650093China

Mineral fulvic acid(MFA)was used as an eco-friendly pyrite depressant to recover chalcopyrite by flotation with the use of the butyl xanthate as a *** experiments showed that MFA produced a stronger inhibition effect on pyrite than on *** separation of chalcopyrite from pyrite was realized by introducing 150 mg/L MFA at a pulp pH of approximately *** copper grade,copper recovery,and separation efficiency were 28.03%,84.79%,and 71.66%,*** adsorption tests,zeta potential determinations,and localized electrochemical impedance spectroscopy tests showed that more MFA adsorbed on pyrite than on chalcopyrite,which weakened the subsequent interactions between pyrite and the *** force microscope imaging further confirmed the adsorption of MFA on pyrite,and X-ray photoelectron spectroscopy results indicated that hydrophilic Fe-based species on the pyrite surfaces increased after exposure of pyrite to MFA,thereby decreasing the floatability of pyrite.

关键词： mineral fulvic acid chalcopyrite pyrite flotation separation

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Prognostic roles nutritional index in patients with resectable and advanced biliary tract cancers

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World Journal of Gastroenterology 2025年第6期31卷 76-88页

作者： Di Zeng Ning-Yuan wen yao-Qun Wang Nan-Sheng Cheng Bei Li Division of Biliary Surgery Department of General SurgeryWest China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Research Center for Biliary Diseases West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina

BACKGROUND Biliary tract cancer(BTC)is a rare,aggressive malignancy with increasing inci-dence and poor *** preoperative prognostic factors is crucial for effective risk-benefit assessments and patient *** prognostic nutritional index(PNI),which reflects immune-inflammatory and nutritional status,has shown prognostic value in various cancers,but its significance in BTC remains *** To assess the prognostic value of the preoperative PNI in BTC patients,with a focus on overall survival(OS)and disease-free survival(DFS).METHODS Comprehensive searches were conducted in the PubMed,EMBASE,and Web of Science databases from inception to April *** primary outcomes of interest focused on the associations between the preoperative PNI and the prognosis of BTC patients,specifically OS and disease-free survival(DFS).Statistical analyses were conducted via STATA 17.0 *** Seventeen studies encompassing 4645 patients met the inclusion ***-analysis revealed that a low PNI was significantly associated with poorer OS[hazard ratio(HR)1.91,95%CI:1.59-2.29;P<0.001]and DFS(HR 1.93,95%CI:1.39-2.67;P<0.001).Subgroup analyses revealed consistent results across BTC subtypes(cholangiocarcinoma and gallbladder cancer)and stages(resectable and advanced).Sensitivity analyses confirmed the robustness of these findings,and no significant publication bias was *** This study demonstrated that a low preoperative PNI predicts poor OS and DFS in BTC patients,highlighting its potential as a valuable prognostic *** prospective studies are needed to validate these findings and enhance BTC patient management.

关键词： Biliary tract cancer Prognostic nutritional index Predictive marker Meta-analysis Survival outcomes

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Planar Hall plateau in magnetic Weyl semimetals

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Science Bulletin 2025年第2期70卷 187-192页

作者： Lei Li Chaoxi Cui Run-Wu Zhang Zhi-ming Yu Yugui yao Centre for Quantum Physics Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement(MOE)School of PhysicsBeijing Institute of TechnologyBeijing 100081China Beijing Key Lab of Nanophotonics&Ultrafine Optoelectronic Systems School of PhysicsBeijing Institute of TechnologyBeijing 100081China International Center for Quantum Materials Beijing Institute of TechnologyZhuhai 519000China

Despite the rapid progress in the study of planar Hall effect(PHE)in recent years,all the previous works only showed that the PHE is connected to local geometric quantities,such as Berry ***,for the first time,we point out that the PHE in magnetic Weyl semimetals is directly related to a global quantity,namely,the Chern number of the Weyl *** leads to a remarkable consequence that the PHE observation predicted here is robust against many system details,including the Fermi *** main difference between non-magnetic and magnetic Weyl points is that the latter breaks time-reversal symmetry T,thus generally possessing an energy *** semiclassical Boltzmann theory,we investigate the PHE in generic magnetic Weyl models with energy tilt and arbitrary Chern *** find that by aligning the magnetic and electric fields in the same direction,the trace of the PHE conductivity contributed by Berry curvature and orbital moment is proportional to the Chern number and the energy tilt of the Weyl points,resulting in a previously undiscovered quantized PHE plateau by varying the Fermi *** further confirm the existence of PHE plateaus in a more realistic lattice model without T *** proposing a new quantized physical quantity,our work not only provides a new tool for extracting the topological character of the Weyl points but also suggests that the interplay between topology and magnetism can give rise to intriguing physics.

关键词： Magnetic Weyl semimetals Planar Hall effect Quantized plateau Chern number

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Understanding and probing progression of localized corrosion on inner walls of steel pipelines:an overview

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Journal of Iron and Steel Research International 2025年第1期32卷 1-18页

作者： ming-yu Wang Hai-yuan yao Yong-fei Liu Ye-sen Zhu Wan-bin Chen Yun-ze Xu Yi Huang School of Naval Architecture and Ocean Engineering Dalian University of TechnologyDalian 116024LiaoningChina China National Offshore Oil Corporation Research Institute Co. Ltd.Beijing 100028China State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentDalian University of TechnologyDalian 116024LiaoningChina

Corrosion poses a major threat to the safety of transportation ***,it is crucial to have an in-depth understanding of corrosion mechanisms in pipeline steels for the effective management of pipeline *** research on corrosion mechanisms relies on the use of efficient and reliable corrosion monitoring and analysis *** advancements in corrosion monitoring techniques specifically designed for the localized corrosion monitoring were aimed to be introduced,and a comprehensive overview of recent progress in understanding the localized corrosion mechanisms in pipeline steels was *** on the different corrosive environments encountered,the localized corrosion issues inside pipelines are classified into two categories:localized corrosion primarily influenced by electrochemical processes and localized corrosion controlled by both electrochemical and mechanical ***,a thorough analysis of the synergistic effects between micro-cell and macro-cell currents,as well as the interplay of mechanics and electrochemistry is ***,recommendations for future research on the mechanisms of internal localized corrosion in pipelines are provided.

关键词： Pipeline steel Localized corrosion Corrosion type Corrosion monitoring Corrosion mechanism

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A Preliminary Catalog of Early Aftershocks Following the 7 January 2025 MS6.8 Dingri,Xizang Earthquake

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Journal of Earth Science 2025年

作者： Jiayuan yao Dongdong yao Fang Chen ming Zhi Li Sun Dun Wang Hubei Subsurface Multi-scale Imaging Key Laboratory School of Geophysics and GeomaticsChina University of Geosciences State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences(Wuhan) State Key Laboratory of Geological Processes and Mineral Resources School of Earth SciencesChina University of Geosciences(Wuhan) China Earthquake Networks Center

INTRODUCTION On January 7,2025,at 9:05 AM BJT,a MS6.8 earthquake （CENC epicenter:28.50°N,87.45°E） struck Dingri County,Xizang Province （hereinafter referred to as the Dingri mainshock）.The inferred moment magnitude,based on regional/teleseismic waveform inversion and back-projection,is approximately *** mechanism solutions,aftershock distribution,and field surveys indicate that the Dingri mainshock was a normal-faulting event,with a nearly north-south strike and a westwarddipping fault plane.

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Unified monogamy relations for the generalized W-class states beyond qubits

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Communications in Theoretical Physics 2025年第2期77卷 72-82页

作者： Zhong-Xi Shen wen Zhou Dong-Ping Xuan Zhi-Xi Wang Shao-ming Fei School of Mathematical Sciences Capital Normal University

The monogamy of entanglement stands as an indispensable feature within multipartite quantum systems. We study monogamy relations with respect to any partitions for the generalized W-class（GW） states based on the unified-（q, s） entanglement（UE）. We provide the monogamy relation based on the squared UE for a reduced density matrix of a qudit GW state, as well as tighter monogamy relations based on the αth（α ≥ 2） power of UE. Furthermore, for an n-qudit system ABC1...Cn-2, a generalized monogamy relation and an upper bound satisfied by the βth（0 ≤ β ≤ 1） power of the UE for the GW states under the partition AB and C1...Cn-2are established. In particular, two partition-dependent residual entanglements for the GW states are analyzed in detail.

关键词： monogamy of entanglement unified-(q,s) entanglement generalized W-class state

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多阻挡因素下无线网络非均匀分布节点部署

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计算机仿真 2021年第11期38卷 314-318页

作者：廖伟国文明瑶华南农业大学珠江学院广东广州510900

由于无线网络分布节点部署中的阻挡因素较多,因此从多种阻挡因素出发,提出一种无线网络非均匀分布节点部署方法。以概率感知模型为基础,进一步改善环境与节点感知能力的关系,构建统计节点感知模型,并估计需要部署的总节点数。综合多种... 详细信息

由于无线网络分布节点部署中的阻挡因素较多,因此从多种阻挡因素出发,提出一种无线网络非均匀分布节点部署方法。以概率感知模型为基础,进一步改善环境与节点感知能力的关系,构建统计节点感知模型,并估计需要部署的总节点数。综合多种阻挡因素对任意点在监测区域的联合探测概率,初步确定覆盖空洞的区域,进而确定覆盖空洞位置。构建赋权二部图调度移动节点,使得移动节点向覆盖空洞处移动,以实现非均匀分布节点的部署。实验结果证明,该方法的动态节点与静态节点的节点覆盖程度均较高,能够实现良好的无线网络性能;能量消耗低于原有方法,交换信息包数大于原有方法,具备良好的节点定位性能,实用性较强。

关键词：多阻挡因素无线网络非均匀分布节点节点部署统计节点感知模型覆盖空洞

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基于机器学习的不确定数据增量式挖掘算法

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计算机仿真 2021年第11期38卷 290-294页

作者：文明瑶廖伟国华南农业大学珠江学院广东广州510900

以实现数据增量式精准挖掘为目的,提出基于机器学习的不确定数据增量式挖掘算法。以机器学习算法中的模糊c-均值聚类(FCM)算法为基础,通过主成分分析法筛选原始数据集中指标,利用Relief算法计算指标权重,实现FCM算法改进。改进FCM算法... 详细信息

以实现数据增量式精准挖掘为目的,提出基于机器学习的不确定数据增量式挖掘算法。以机器学习算法中的模糊c-均值聚类(FCM)算法为基础,通过主成分分析法筛选原始数据集中指标,利用Relief算法计算指标权重,实现FCM算法改进。改进FCM算法通过阈值定义目标函数,经样本数据分类、特征提取和聚类,使目标函数达到最小值,实现数据挖掘。实验结果表明,上述算法的数据样本分类符合率可达99.28%,分类准确率在98%左右,且分类耗时短、效率高;特征提取能力受数据量增加影响较小;在数据增量情况下,改进算法增量式挖掘准确率保持在95%~98%之间,且所需迭代次数少。

关键词：机器学习增量式数据挖掘聚类

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