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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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C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 pathway as a therapeutic target and regulatory mechanism for spinal cord injury

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Neural Regeneration Research 2025年第8期20卷 2231-2244页

作者： Xiangzi Wang Xiaofei Niu Yingkai Wang Yang Liu Cheng Yang Xuyi Chen Zhongquan Qi school of Medicine Guangxi UniversityNanningGuangxi Zhuang Autonomous RegionChina graduate school of Tianjin University of Traditional chinese Medicine TianjinChina Characteristic Medical Center of People’s Armed Police Forces TianjinChina Fujian Maternity and Child Health Hospital FuzhouFujian ProvinceChina

Spinal cord injury involves non-reversible damage to the central nervous system that is characterized by limited regenerative capacity and secondary inflammatory *** expression of the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis exhibits significant differences before and after *** studies have revealed that the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis is closely associated with secondary inflammatory responses and the recruitment of immune cells following spinal cord injury,suggesting that this axis is a novel target and regulatory control point for *** review comprehensively examines the therapeutic strategies targeting the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis,along with the regenerative and repair mechanisms linking the axis to spinal cord ***,we summarize the upstream and downstream inflammatory signaling pathways associated with spinal cord injury and the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 *** review primarily elaborates on therapeutic strategies that target the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis and the latest progress of research on antagonistic drugs,along with the approaches used to exploit new therapeutic targets within the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis and the development of targeted ***,there are presently no clinical studies relating to spinal cord injury that are focusing on the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 *** review aims to provide new ideas and therapeutic strategies for the future treatment of spinal cord injury.

关键词： apoptosis C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 pathway C-C motif chemokine receptor 2 antagonists chemokine ligand 2 chemokine receptor 2 inflammation macrophage microglia spinal cord injury therapeutic method

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Disturbance effects on community structure of Ficus tinctoria fig wasps in Xishuangbanna, China： Implications for the fig/fig wasp mutualism

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Insect Science 2009年第5期16卷 417-424页

作者： Wen-Juan Ma Da-Rong Yang Yan-Qiong Peng Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Kunming graduate school of the chinese academy ofsciences Beijing China

Fig trees are important components of tropical forests, because their fruits are eaten by so many vertebrates, but they depend on pollinating fig wasps to produce mature fruits. Disturbance to habitat structure can have a major impact on insect diversity and com- position, potentially reducing fruit yields. We investigated the impact of habitat disturbance on the fig wasp community associated with male figs ofFicus tinctoria in Xishuangbanna, China. The community comprised one pollinator species Liporrhopalum gibbosae and six non-pollinating wasp species： Sycoscapter sp. 1, Philotrypesis ravii, Philotrypesis sp. 1, Neosycophila omeomorpha, Sycophila sp.1, and Walkerella sp.1. More disturbed areas were characterized by higher temperatures, less shade, and more vehicle noise. The response of the fig wasp community was complex, with no simple relationship between intensity of disturbance and pollinator abundance. However, the sex ratios （proportion of male progeny） of pollinators increased significantly in more disturbed areas. We conclude that potential changes in fig wasp community composition brought about by disturbance, are unpredictable, with unclear consequences for tropical rainforest biodiversity.

关键词： disturbance Ficus tinctoria fig/fig wasp mutualism wasp community

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Development of the bunch-by-bunch beam current acquisition system at SSRF

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Nuclear Science and Techniques 2009年第2期20卷 71-75页

作者： HUANG Siting LENG Yongbin YAN Yingbing Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China graduate school of chinese academy ofsciences Beijing 100049 China

In this paper,we report the development of a bunch-by-bunch beam current acquisition *** a waveform-reconstruction algorithm,the system realizes high equivalent sampling rate with a relatively low inherent *** on the EPICS environment,information communication with other systems can be *** test results in commissioning the SSRF storage ring show that the system can reconstruct the beam waveform of single bunch,providing a convenient and reliable method for the top-up operation in the future.

关键词：采集系统 SSRF 束流重建算法系统实现信息通信采样率储存环

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Different Features of Jets and Isotropic Fireballs in Gamma-ray Burst Phase

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chinese Journal of Astronomy and Astrophysics 2006年第1期6卷 69-76页

作者： Yun-Ming Dong Lan-Wei Jia Xiao-Hong Zhao Yunnan Astronomical Observatory/National Astronomical Observatories Chinese Academy ofSciences Kunming 650011 graduate University of chinese academy of Sciences Beijing 100049

We investigated physical quantities including the spectrum, emission lines and pulse profiles expected from a uniform jet, a spherical fireball and the 1/Г region （the portion of the spherical fireball with opening angle 1/Г） in the prompt emission phase, after taking into consideration of the Doppler effect under the fireball framework. Our study shows that： a） for these physical quantities the spherical fireball and the uniform jets do not present obvious differences, so we cannot use these to distinguish a spherical fireball from a uniform jet; b） for the spherical fireball and a uniform jet, the observed quantities mainly come from the 1/Г region, so we can simply use the 1/Г region in approximate calculations; c） broadening of emission lines is a general phenomena, which mainly comes from the curvature effect; d） the 1/Г region plays different roles in different frequency ranges, and the radiation from the 1/Г region is greater in the higher than in the lower frequencies.

关键词： gamma-rays: bursts--gamma-rays: theory--radiation mechanisms: non-thermal --relativity

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Influence of core property on multi-electron process in slow collisions of isocharged sequence ions with neon

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chinese Physics B 2010年第11期19卷 475-488页

作者：卢荣春于得洋邵曹杰阮芳芳蔡晓红 Institute of Modern Physics Chinese Academy of Sciences graduate school of the chinese academy of Sciences

Influence of core property on multi-electron process in the collisions of q = 6-9 and 11 isocharged sequence ions with Ne is investigated in the keV/u region. The cross-section ratios of double-, triple-, quadruple- and total multielectron processes to the single electron capture process as well as the partial ratios of different reaction channels to the relevant multi-electron process are measured by using position-sensitive and time-of-flight techniques. The experimental data are compared with the theoretical predictions including the extended classical over-barrier model, the molecular Columbic barrier model and the semi-empirical scaling law. Results show a core effect on multi-electron process of isocharge ions colliding with Neon, which is consistent with the results of Helium we obtained previously.

关键词： isocharged sequence ions multi-electron process classical over-barrier model

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An assessment of the effectiveness and impact of electrokinetic remediation for pyrene-contaminated soil

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Journal of Environmental Sciences 2014年第11期26卷 2290-2297页

作者： Sujuan Xu Shuhai Guo Bo Wu Fengmei Li Tingting Li Institute of Applied Ecology Chinese Academy of Sciences graduate school of chinese academy of Sciences

The effectiveness of electrokinetic remediation for pyrene-contaminated soil was investigated by an anode-cathode separated system using a salt bridge. The applied constant voltage was 24 V and the electrode gap was 24 cm. Two types of soil （sandy soil and loam soil） were selected because of their different conductive capabilities. The initial concentrations of pyrene in these soil samples were 261.3 mg/kg sandy soil and 259.8 mg/kg loam soil After treatment of the sandy soil and loam soil for seven days, 56.8% and 20.1% of the pyrene had been removed respectively. Under the same power supply voltage, the removal of the pollutant from the sandy soil was greater than that from the loam soil, due to the higher current and lower pH. Further analysis revealed that the effectiveness of electrokinetic remediation was affected by the energy expenditure, and was associated with changes in soil properties.

关键词： Electrokinetie remediation Anode-cathode separated system Electrochemical oxidation Soil Pyrene

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Structural modification of C_(60) films induced by 300-keV Xe-ion irradiation

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chinese Physics B 2011年第7期20卷 325-330页

作者：姚存峰金运范王志光庞立龙申铁龙朱亚滨 Institute of Modern Physics Chinese Academy of Sciences graduate school of chinese academy of Sciences

The structural modification of C60 films induced by 300-keV Xe-ion irradiation was investigated. The irradiated C60 films were analysed using Fourier transform infrared spectroscopy, the Raman scattering technique, ultraviolet/visible spectrophotometry and atomic force microscopy. The analysis results indicate that the Xe-ion irradiation induces polymerization and damage of the C60 molecule and significantly modifies the surface morphology and the optical property of the C60 films. The damage cross-section for the C60 molecule was also evaluated.

关键词： C60 films ions irradiation damage polymerization

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Magnetic properties of Mn-doped ZnO diluted magnetic semiconductors

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chinese Physics B 2008年第4期17卷 1371-1376页

作者：刘学超张华伟张涛陈博源陈之战宋力昕施尔畏 Shanghai Institute of Ceramics Chinese Academy of Sciences graduate school of the chinese academy of Sciences

A series of Mn-doped ZnO films have been prepared in different sputtering plasmas by using the inductively coupled plasma enhanced physical vapour deposition. The films show paramagnetic behaviour when they are deposited in an argon plasma. The Hall measurement indicates that ferromagnetism cannot be realized by increasing the electron concentration. However, the room-temperature ferromagnetism is obtained when the films are deposited in a mixed argon-nitrogen plasma. The first-principles calculations reveal that antiferromagnetic ordering is favoured in the case of the substitution of Mn^2＋ for Zn^2＋ without additional acceptor doping. The substitution of N for O （NO^-） is necessary to induce ferromagnetic couplings in the Zn-Mn-O system. The hybridization between N 2p and Mn 3d provides an empty orbit around the Fermi level. The hopping of Mn 3d electrons through the empty orbit can induce the ferromagnetic coupling. The ferromagnetism in the N-doped Zn-Mn-O system possibly originates from the charge transfer between Mn^2＋ and Mn^3＋ via NO^-, The key factor is the empty orbit provided by substituting N for O, rather than the conductivity type or the carrier concentration.

关键词： Mn-doped ZnO diluted magnetic semiconductors first-principle calculations

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Optical properties and local structure of Dy^(3+)-doped chalcogenide and chalcohalide glasses

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Journal of Rare Earths 2008年第6期26卷 889-894页

作者：唐高杨志勇罗澜陈玮 Shanghai Institute of Ceramics Chinese Academy of Sciences graduate school of the chinese academy of Sciences

Dy^3＋-doped Ge-Ga-Se chalcogenide glasses and GeSe2-Ga2Se3-CsI chalcohalide glasses were prepared. The absorption, emission properties, and local structure of the glasses were investigated. When excited at 808 nm diode laser, intense 1.32 and 1.55 μm near-infrared luminescence were observed with full width at half maximum （FWHM） of about 90 and 50 nm, respectively. The lifetime of the 1.32 μm emission varied due to changes in the local structure surrounding Dy^3＋ ions. The longest lifetime was over 2.5 ms, and the value was significantly higher than that in other Dy^3＋-doped glasses. Some other spectroscopic parameters were calculated by using Judd-Ofelt theory. Meanwhile, Ge-Ga-Se and GeSe2-Ga2Se3-CsI glasses showed good infrared transmittance. As a result, Dy^3＋-doped Ge-Ga-Se and GeSe2-Ga2Se3-CsI glasses were believed to be useful hosts for 1.3 μm optical fiber amplifier.

关键词： chalcogenide glass chalcohalide glass optical properties microstructure 1.3 μm optical fiber amplifier rare earths

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