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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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富氢水对肉鸡生长性能、抗氧化能力、肉品质和盲肠微生物的影响

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南京农业大学学报 2025年第1期48卷 180-189页

作者：朱赫王亚梅胡恒姚文郑卫江南京农业大学动物科技学院江苏南京210095

[目的]本试验旨在研究饮用富氢水对肉鸡生长性能、抗氧化能力、肉品质和盲肠微生物群影响。[方法]选取120只1日龄雄性AA肉鸡,随机分成2组(每组6个重复,每个重复10只鸡),对照组饮用自来水,富氢水组饮用富氢水,试验期为42 d。[结果]虽然... 详细信息

[目的]本试验旨在研究饮用富氢水对肉鸡生长性能、抗氧化能力、肉品质和盲肠微生物群影响。[方法]选取120只1日龄雄性AA肉鸡,随机分成2组(每组6个重复,每个重复10只鸡),对照组饮用自来水,富氢水组饮用富氢水,试验期为42 d。[结果]虽然富氢水对肉鸡生长性能无显著影响,但可显著提高血清总抗氧化能力、超氧化物歧化酶活性和肝脏过氧化氢酶活性(P<0.05),显著降低肝脏活性氧和丙二醛含量(P<0.05)。在鸡胸肉的肉品质方面,富氢水组剪切力显著低于对照组(P<0.05);此外,富氢水组鸡胸肉中亮氨酸、赖氨酸及必需氨基酸比例显著高于对照组(P<0.05),十一烷酸比例显著低于对照组(P<0.05),棕榈油酸、油酸、芥酸、γ-亚麻油酸、α-亚麻油酸及单不饱和脂肪酸比例显著高于对照组(P<0.05)。与对照组相比,富氢水可显著提高盲肠食糜中产丁酸盐菌(Mediterraneibacter、Kineothrix、Roseburia)和寡养单胞菌属(Stenotrophomonas)相对丰度(P<0.05),而显著降低Massilimaliae和共生小杆菌属(Symbiobacterium)相对丰度(P<0.05)。[结论]富氢水对肉鸡生长性能无显著影响,但对血清和肝脏的部分抗氧化指标起到积极作用,还可提高盲肠食糜中部分产丁酸盐菌群的丰度,并通过改善氨基酸与脂肪酸组成调节肉鸡鸡胸肉品质。

关键词：富氢水肉鸡抗氧化能力肉品质盲肠微生物

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Reinforcement learning based adaptive control for uncertain mechanical systems with asymptotic tracking

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Defence Technology（防务技术） 2024年第4期34卷 19-28页

作者： Xiang-long Liang Zhi-kai yao yao-wen Ge Jian-yong yao School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China College of Automation&College of Artificial Intelligence Nanjing University of Post and TelecommunicationNanjing210023China

This paper mainly focuses on the development of a learning-based controller for a class of uncertain mechanical systems modeled by the Euler-Lagrange *** considered system can depict the behavior of a large class of engineering systems,such as vehicular systems,robot manipulators and *** these systems are often characterized by highly nonlinear characteristics,heavy modeling uncertainties and unknown perturbations,therefore,accurate-model-based nonlinear control approaches become *** by the challenge,a reinforcement learning(RL)adaptive control methodology based on the actor-critic framework is investigated to compensate the uncertain mechanical *** approximation inaccuracies caused by RL and the exogenous unknown disturbances are circumvented via a continuous robust integral of the sign of the error(RISE)control *** from a classical RISE control law,a tanh(·)function is utilized instead of a sign(·)function to acquire a more smooth control *** developed controller requires very little prior knowledge of the dynamic model,is robust to unknown dynamics and exogenous disturbances,and can achieve asymptotic output ***,co-simulations through ADAMS and MATLAB/Simulink on a three degrees-of-freedom(3-DOF)manipulator and experiments on a real-time electromechanical servo system are performed to verify the performance of the proposed approach.

关键词： Adaptive control Reinforcement learning Uncertain mechanical systems Asymptotic tracking

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Structure and Aromaticity of AlCO-substituted Semibullvalene

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Chinese Journal of Structural Chemistry 2007年第8期26卷 897-901页

作者： yao wen-Zhi WU Hai-Shun Chemistry and Material Science Institute Shanxi Normal University Linfen 041004 China

The structures, energies and aromaticity （the nuclear-independent chemical shifts,NICS） of AlCO-substituted semibullvalenes were investigated at the B3LYP/6-311＋G＊＊ *** to BCO-substituted analogues, [2,6]-AlCO-semibullvalene is neutral *** NICS values reveal that the aromaticity of AlCO-substituted structures is smaller than that of BCO analogues.

关键词： DFT semibullvalene AlCO aromaticity

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Is playing-as-downloading feasible in an eMule P2P file sharing system?

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第6期11卷 465-475页

作者： wen-yi WANG yao-wu CHEN Advanced Digital Technology and lnstruments Institute Zhejiang University Hangzhou 310027 China

Peer-to-peer(P2P) swarm technologies have been shown to be very efficient for large scale content distribution systems, such as the well-known BitTorrent and eMule ***, these systems have been designed for generic file sharing with little consideration of media streaming support, and the user cannot start a movie playback before it is completely *** playing-as-downloading capability would be particularly useful for a downloading peer to evaluate if a movie is valuable to be downloaded, and it could also help the P2P content distribution system to locate and eliminate the polluted *** this paper we address this issue by introducing a new algorithm, wish driven chunk distribution(WDCD), which enables the P2P file sharing system to support the video-on-demand(VOD) function while keeping the P2P native downloading speed.A new parameter named next-play-frequency is added to the content chunk to strike a replication balance between downloading and streaming *** modify the eMule as the test bed by adding the WDCD algorithm and then verify the prototype implementation by *** experimental results show that the proposed algorithm can keep the high downloading throughput performance of the eMule system with a good playing-as-downloading function.

关键词： Peer-to-peer(P2P) Video-on-demand(VOD) Playing-as-downloading eMule

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Acyclic Edge Coloring of Triangle-free 1-planar Graphs

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Acta Mathematica Sinica,English Series 2015年第10期31卷 1563-1570页

作者： wen yao SONG Lian Ying MIAO Institute of Mathematics China University of Mining and TechnologyXuzhou

A proper edge coloring of a graph G is acyclic if there is no 2-colored cycle in G. The acyclic chromatic index of G, denoted by X＇a（G）, is the least number of colors such that G has an acyclic edge coloring. A graph is 1-planar if it can be drawn on the plane so that each edge is crossed by at most one other edge. In this paper, it is proved that X＇a（G） ≤△ A（G）＋ 22, if G is a triangle-free 1-planar graph.

关键词： Acyclic chromatic index acyclic edge coloring 1-planar graph

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The dynamic response of a high-density polyethylene slow-release structure under launching overload

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Defence Technology（防务技术） 2023年第8期26卷 143-156页

作者： Ke-Bin Zhang wen-Bin Li Yu Zheng wen-Jin yao Chang-Fang Zhao School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China

Based on the 60 mm artillery grenade,a slow-release structure was designed to reduce the severity of ammunitions response to accidental thermal stimulation and improve the thermal stability of *** slow-release structure was made of high-density polyethylene(HDPE) and connected the fuse and the projectile body through internal and external *** study the safety of the slowrelease structure under artillery launching overload,mechanical analysis of the slow-release structure was simulated via finite element analysis(FEA).The impacts of various factors(e.g.,fuse mass,number of threads,and nominal diameter of internal threads of the slow-release structure) on the connection strength of the slow-release structure were studied.A strength-prediction model based on the fuse mass and internal thread parameters was established by fitting the maximum effective stress of the slowrelease *** led to good prediction *** conclusion,this study provides references and theoretical support for the design of thermal protection structures insensitive to ammunition.

关键词： Artillery ammunition HDPE Finite element analysis Slow-release structure Threaded connection

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A novel current-sharing scheme based on magamp

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第8期9卷 1150-1156页

作者： wen-xi yao Xiao-yuan HONG Zheng-yu LU School of Electrical Engineering Zhejiang University Hangzhou 310027 China

The magamp (magnetic amplifier) is widely used in power supplies due to its low cost, simplicity and other advan-tages. This paper discusses a novel application of the magamp in switching power supplies, where the magamp is used to regulate pulse width modulation (PWM) instead of power signal in the main circuit. This method extends the application of the magamp in power supplies, and makes it possible to further regulate control signal when PWMs have been generated. Based on this applica-tion, a new current-sharing (CS) scheme using the magamp is proposed, which uses a modified inner loop CS structure. In this scheme PWMs are generated by one main controller, and CS is achieved by regulating PWMs using a magamp in each module. Compared with traditional application of the magamp, the new CS scheme can be used in most topologies and only requires magamps of low power capacity. Then a test circuit of parallel power supply is developed, in which CS is achieved by a PWM regulator with the magamp. The proposed scheme is also used to upgrade an electroplate power to make it capable of paralleling supplies. Experimental results show that the proposed scheme has good CS performance.

关键词： Current-sharing (CS) Magnetic amplifier (magamp) Parallel

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Reducing porcine corneal graft rejection, with an emphasis on porcine endogenous retrovirus transmission safety: a review

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International Journal of Ophthalmology(English edition) 2019年第2期12卷 324-332页

作者： yao-wen Song Zhi-Qiang Pan Beijing Tongren Eye Center Beijing Tongren Hospital Capital Medical University Beijing Ophthalmology and Visual Science Key Laboratory

Donor cornea shortage is a primary hurdle in the development of corneal transplantation. Of all species, porcine corneas are the ideal transplantation material for humans. However, the xenoimmune rejection induced by porcine corneal xenotransplantation compromises surgical efficacy. Although the binding of IgM/IgG in human serum to a genetically modified porcine cornea is significantly weaker than that of the wild type(WT), genetically modified porcine corneas do not display a prolonged graft survival time in vivo. Conversely, costimulatory blockade drugs, such as anti-CD40 antibodies, can reduce the xenoimmune response and prolong graft survival time in animal experiments. Moreover, porcine endothelial grafts can survive for more than 6mo with only the subconjunctival injection of a steroid-based immunosuppressants regime; therefore, they show great value for treating corneal endothelial disease. In addition, zoonotic transmission is a primary concern of xenotransplantation. Porcine endogenous retrovirus(PERV) is the most significant virus assessed by ophthalmologists. PERV integrates into the porcine genome and infects human cells in vitro. Fortunately, no evidence from in vivo studies has yet shown that PERV can be transmitted to hosts.

关键词： corneal xenotransplantation genetically modified pigs wild type pigs costimulatory blockade drugs porcine endothelial grafts porcine endogenous retrovirus safety

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Morphological and molecular response of small intestine to lactulose and hydrogen-rich water in female piglets fed Fusarium mycotoxins contaminated diet

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Journal of Animal Science and Biotechnology 2019年第3期10卷 694-707页

作者： Xu Ji Qing Zhang Weijiang Zheng wen yao Laboratory of Gastrointestinal Microbiology Jiangsu Key Laboratory of Gastrointestinal Nutrition and Animal HealthCollege of Animal Science and TechnologyNanjing Agricultural UniversityNanjing 210095JiangsuChina Key Lab of Animal Physiology and Biochemistry Ministry of AgricultureNanjing 210095JiangsuChina

Background: Following the intake of Fusarium mycotoxin-contaminated feed,small intestines may be exposed to high levels of toxic substances that can potentially damage intestinal functions in *** is well known that Fusarium mycotoxins will lead a breakdown of the normally impeccable epithelial barrier,resulting in the development of a "leaky" gut.H2 administration with different methods has been proved definitely potentials to prevent serious intestinal *** goal of this study is to investigate the roles of lactulose(LAC) and hydrogenrich water(HRW) in preventing intestinal dysfunction in piglets fed Fusarium mycotoxin-contaminated ***: A total of 24 female piglets were evenly assigned to 4 groups: negative control(NC) group,mycotoxincontaminated(MC) feed group,MC feed with LAC treatment(MC + LAC),and MC feed with HRW treatment(MC +HRW),*** in the NC group were fed uncontaminated control diet,while remaining piglets were fed Fusarium mycotoxin-contaminated *** the NC and MC groups,10 mL/kg body weight(BW) of hydrogen-free water(HFW) was orally administrated to piglets twice daily;while in the MC + LAC and MC + HRW groups,piglets were treated with the same dose of LAC solution(500 mg/kg BW) and HRW twice daily,*** d 25,serum was collected and used for biochemical *** tissues were sampled for morphological examination as well as relative genes and protein expression ***: Our data showed that Fusarium mycotoxins induced higher serum diamine oxidase(DAO) activities(P < 0.05),D-lactic acid levels(P < 0.01),and endotoxin status(P < 0.01),lower villus height(P < 0.01) and ratio of villus height to crypt depth(P < 0.05) in small intestine,greater apoptosis index and higher mRNA expression related to tight junctions(P < 0.05).In addition,the distribution and down-regulation of claudin-3(CLDN3) protein in the small intestinal was also *** expected,oral administrations of HRW and L

关键词： Fusarium mycotoxins Hydrogen-rich water Lactulose Piglets Small intestine

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