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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

Preparation of modified Composite Nanofiltration membrane Synergistically Using Carboxylic multi- walled Carbon Nanotube and β-cyclodextrin

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Journal of Wuhan University of Technology(materials Science) 2025年第1期40卷 232-239页

作者： LIU Peng mAO Junpeng FANG Yanfeng YU Yunwu CHEN Changxiu tang Ning WAN Ye GU Yaxin LIU Yunxue WANG Lihua School of materials Science and Engineering Shenyang Jianzhu UniversityShenyang 110168China

A new modified blend ultrafiltration(UF)membrane with good hydrophilicity,high porosity and excellent anti-fouling performance was developed by using carboxylic multi-walled carbon nanotube(CmWCNT)as casting solution ***,a composite nanofiltration(NF)membrane with large water flux and good retention rate was fabricated by using the PVDF/CmWCNT blend UF membrane as the substrate,and polyvinyl alcohol(PVA),β-cyclodextrin(β-CD)and polyethylenimine(PEI)as the coating *** results show that with the appropriate addition of CmWCNT in the casting solution,the surface roughness,porosity and recovery rate of the PVDF/CmWCNT blend UF membrane is obviously *** water flux of blend UF membrane is significantly improved when the CmWCNT content increases from 0 wt%to 0.2 wt%.The water flux of blend UF membrane with 0.2 wt%CmWCNT is 162.7 L/(m^(2)·h),which is 44.3%higher than that of the pure PVDF ***β-CD content is 0.8 wt%,the retention rate of Congo red by PVDF/CmWCNT/β-CD composite NF membrane reaches 98.7%,which is 28.3%higher than that of single PVA/PEI modified *** research will provide a new idea and simple method for developing novel high-performance composite NF membranes.

关键词： CmWCNT cyclodextrin nanofiltration membrane

Quantum chemical studies on antimalarial of artemisinin (qinghaosu) derivatives

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Chinese Journal of Chemistry 1995年第2期13卷 131-140页

作者： JIANG, HL CHEN, KX tang, Y CHEN, JZ JI, ry CHINESE ACAD SCI SHANGHAI INST MAT MEDSHANGHAI 200031PEOPLES R CHINA

In this paper theoretical studies were performed on artemisinin (qinghaosu) derivatives with semiempirical quantum chemical methods Am1 and Pm3. The antimalarial activity -logC has an obvious correlation with the net charge of C(16) and bond orders of bonds O(1)-C(10), O(2)-C(6), O(1)-O(2) and O(5)-C(16). According to the calculation results, we derived structure-activity relationship, presented the probable pharmacophore of qinghaosu derivatives and the interaction fashion between the drugs and the plasmodium receptor.

关键词： ARTEmISININ (QINGHAOSU) ANTImALARIAL QUANTUm CHEmISTry PHARmACOPHORE

Distinct mLT asymmetry of auroral kilometric radiation observed by the FAST satellite

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Earth and Planetary Physics 2025年第1期9卷 188-193页

作者： JiaWen tang Sai Zhang FuLiang Xiao Hongming Yang Si Liu YiHua He Chang Yang YuYue Jin ZhouKun Deng Ping Li Archie James Johnston School of Physics and Electronic Sciences Changsha University of Science and TechnologyChangsha 410114China Hunan Province Higher Education Key Laboratory of modeling and monitoring on the Near-Earth Electromagnetic Environments Changsha University of Science and TechnologyChangsha 410114China School of Electrical and Information Engineering Changsha University of Science and TechnologyChangsha 410114China

Auroral Kilometric Radiation (AKR) is a common radio emission,which can contribute to the magnetosphere-ionosphereatmosphere co u *** emissions have been observed in all magnetic planet magnetospheres of the solar *** this study,using observations from the FAST satellite from 30 August 1996 to 9 September 2001,the distribution of AKR in altitude=500-4500 km and invariant latitude (|ILAT|)=60°-80°has been analyzed.63045 AKR samples have been identified with~48%(52%) samples on the dayside (nightside).Of considerable interest,there is a distinct mLT asymmetry with the high occurrence rate in mLT=05-08 and 18-22(02-05 and 12-17) in the northern (southern) *** distinct mLT asymmetry is associated with the direction of Bxof the interplaneta ry magnetic *** addition,the occurrence rate on the nightside clearly increases as the AE^(*) index *** study further enriches the information and understanding of AKR in the magnetosphere as well as other similar radio emissions.

关键词： asymmetry auroral kilometric radiation interplanetary magnetic field

STUDIES　ON　CHIRAL　THIOPHOSPHORIC　ACIDS　AND　THEIR　DERIVATIVES　***　ASYmmETRIC　CYCLIZATION　OF　（＋）－SUBSTITUTED　CYCLOPENTANODIAmINE　WITH　O－AryL　THIOPHOSPHOROCHLORIDATES

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Chinese Chemical Letters 1996年第3期7卷 205-206页

作者： tang, CC Lang, HF Wu, LG He, ZJ Chen, ry NANKAI UNIV INST ELEMENTOORGAN CHEMTIANJIN 300071PEOPLES R CHINA

The cyclizations of (+) -cis-1, 2, 2-trimethyl-l,3-diaminocyclopentrie 1derived from D-camphor with O-arylthiophosphorochloridates 2 give products, (+)-2,4,3-diazaphospha-bicyclo [3,2, 1] octane 3, containing two unequal amounts of diastereoisomers,a pair of which (R=OEt) has been successfully separated by silica gel columnchromatography.

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Alternating-current losses in two-layer superconducting cables consisting of second-generation superconductors coated by U-shaped ferromagnetic materials

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Chinese Physics B 2013年第12期22卷 509-513页

作者： Ahmet Cicek Fedai Inanir Fedor Gm.ry Department of Physics Faculty of Arts and Sciences Mehmet Akif Ersoy University Department of Physics Faculty of Arts and Sciences Recep Tayyip Erdog an University Institute of Electrical Engineering Slovak Academy of Sciences Du'bravska' Cesta 9 842 39 Bratislava Slovakia

Alternating-current losses in a two-layer superconducting cable, each layer being composed of 15 closely-spaced rectangular wires made up of second-generation superconductors when the ends of wires are coated by either a non-magnetic or strong ferromagnetic material having a U profile is numerically investigated. Computations are carried out through the finite-element method. The alternating-current losses do not increase significantly if the relative permeability of the coating is increased three orders of magnitude, provided that the current amplitude is less than half of the critical current in a superconducting wire. However, the losses are much higher for ferromagnetic coating if the amplitude of the applied current oscillating at 50 Hz is close to the critical current. The ferromagnetic coating is seen to accumulate the magnetic field lines normally on its surfaces, while the field lines are parallel to the long axes of the wires, leading to more significant flux penetration in the coated regions. This facilitates a uniform low-loss current flow in the uncoated regions of the wires. In contrast, coating with a non-magnetic material gives rise to a considerably smaller current flow in the uncoated regions, whereas the low-loss flow is maintained in the coated regions. moreover, the current flows in opposite directions in the coated and uncoated regions, where the direction in each region is converse for the two materials.

关键词： second-generation superconductor two-layer cable ferromagnetic coating U profile alternating-current losses

A novel flexible nerve guidance conduit promotes nerve regeneration while providing excellent mechanical properties

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Neural Regeneration Research 2025年第7期20卷 2084-2094页

作者： Tong Li Quhan Cheng Jingai Zhang Boxin Liu Yu Shi Haoxue Wang Lijie Huang Su Zhang Ruixin Zhang Song Wang Guangxu Lu Peifu tang Zhongyang Liu Kai Wang Department of Orthopedics the Fourth Medical Center of Chinese PLA General HospitalBeijingChina Department of Training and Sports medicine Characteristic Medical Center of Chinese People’s Armed Police ForceTianjinChina medical School of Chinese PLA BeijingChina Key Laboratory of Bioactive materials for the ministry of Education College of Life SciencesNankai UniversityTianjinChina Department of Orthopedics Tianjin HospitalTianjinChina Department of Rehabilitation medicine Er Quan Hospital of PAPWuxiJiangsu ProvinceChina

Autografting is the gold standard for surgical repair of nerve defects>5 mm in length;however,autografting is associated with potential complications at the nerve donor *** an alternative,nerve guidance conduits may be *** ideal conduit should be flexible,resistant to kinks and lumen collapse,and provide physical cues to guide nerve *** designed a novel flexible conduit using electrospinning technology to create fibers on the innermost surface of the nerve guidance conduit and employed melt spinning to align ***,we prepared disordered electrospun fibers outside the aligned fibers and helical melt-spun fibers on the outer wall of the electrospun fiber *** presence of aligned fibers on the inner surface can promote the extension of nerve cells along the *** helical melt-spun fibers on the outer surface can enhance resistance to kinking and compression and provide *** novel conduit promoted nerve regeneration and functional recovery in a rat sciatic nerve defect model,suggesting that it has potential for clinical use in human nerve injuries.

关键词： aligned fibers anti-kinking helical fibers nerve guidance conduit nerve regeneration peripheral nerve injury topological guidance

Impact of ocean data assimilation on the seasonal forecast of the 2014/15 marine heatwave in the Northeast Pacific Ocean

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 24-31页

作者： Tiantian tang Jiaying He Huihang Sun Jingjia Luo Institute for Climate and Application Research(ICAR)/Key Laboratory of meteorological Disaster Nanjing University of Information Science and TechnologyNanjingChina

A remarkable marine heatwave,known as the“Blob”,occurred in the Northeast Pacific Ocean from late 2013 to early 2016,which displayed strong warm anomalies extending from the surface to a depth of 300 *** study employed two assimilation schemes based on the global Climate Forecast System of Nanjing University of Information Science(NUIST-CFS 1.0)to investigate the impact of ocean data assimilation on the seasonal prediction of this extreme marine *** sea surface temperature(SST)nudging scheme assimilates SST only,while the deterministic ensemble Kalman filter(EnKF)scheme assimilates observations from the surface to the deep *** latter notably improves the forecasting skill for subsurface temperature anomalies,especially at the depth of 100-300 m(the lower layer),outperforming the SST nudging *** excels in predicting both horizontal and vertical heat transport in the lower layer,contributing to improved forecasts of the lower-layer warming during the *** improvements stem from the assimilation of subsurface observational data,which are important in predicting the upper-ocean *** results suggest that assimilating ocean data with the EnKF scheme significantly enhances the accuracy in predicting subsurface temperature anomalies during the Blob and offers better understanding of its underlying mechanisms.

关键词： Seasonal forecast Ocean data assimilation marine heatwave Subsurface temperature

Thermomechanical Processing and Superplasticity of AZ91 magnesium Alloy

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Journal of materials Science & Technology 2004年第3期20卷 295-297页

作者： RongshiCHEN J.J.Blandin m.Suéry QudongWANG EnhouHAN StateKeyLabforCorrosionandProtection InstituteofMetalResearchChineseAcademyofSciencesShenyang110016China InstitutNationalPolytechniquedeGrenoble(INPG)GéniePhysiqueetmécaniquedesmatériaux(GPm2) UMRCNRS5010ENSPGBP4638402Saint-Martind'HéresCedexFrance SchoolofmaterialsScience&Engineering NationalResearchCenterofLightAlloyNetFormingEngineeringShanghaiJiaoTongUniversityShanghai200030China

The effect of extrusion on grain refinement has been studied in the AZ91 cast ingots. It is found that grain sizesmaller than 10μm can be obtained by the extrusion processing. Vickers hardness measurements were also carriedout to evaluate the effect of these processes on the room temperature mechanical properties. The experimentalresults of high temperature tensile tests revealed that the stress was inversely proportional to the square of the grainsize and that the activation energy for superplastic flow was higher than that for grain boundary diffusion.

关键词： magnesium alloy Thermo-mechanical treatment Superplasticity mechanical properties