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Chiral Synthesis of the Key Intermediate of Diterpenoids

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Chinese Chemical Letters 1997年第11期8卷 949-950页

作者： hao, xj Node, MB Fuji, KR Chinese Acad Sci Kunming Inst Bot Kunming 650204 Peoples R China Kyoto Pharmaceut Univ Yamashima Ku Kyoto 607 Japan Kyoto Univ Inst Chem Res Uji 611 Japan

(-)-Methyl(4R, 5S, 10R)-14-methoxypodocarpa-8, 11, 13-triene-19-oate(1), which is the key intermediate for synthesis of diterpenoids, was synthesized from (R)-(+)-2-methyl-2-(2`-nitrovinyl)-delta-valerolactone(2).

关键词： ADDITION ELIMINATION PROCESS NITROOLEFINATION LACTONES

A New Sesquiterpene from Michelia yunnanensis

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Chinese Chemical Letters 1998年第10期9卷 939-940页

作者： Hong, X Wang, BG Zhou, J hao, xj Acad Sinica Kunming Inst Bot Lab Phytochem Kunming 650204 Peoples R China

A new sesquiterpene, 12,13-di-acetoxyl-1,4,6,11-eudesmanetetrol 1, was isolated from Michelia yunnanensis. The structure was elucidated on the basis of spectral data.

关键词： sesquiterpene 12,13-di-acetoxyl-1,4,6,11-eudesmanetetrol Michelia yunnanensis

THE NEW DITERPENE ALKALOIDS FROM ACONITUM TRANSSECTUM

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Chinese Chemical Letters 1996年第2期7卷 135-138页

作者： Gao, LM hao, xj Zhan, SZ Shen, XW Chen, SY NW NORMAL UNIV LANZHOU 730070PEOPLES R CHINA ACAD SINICA KUNMING INST BOTKUNMING 650204PEOPLES R CHINA

Three new diterpene alkaloids, transconitine A, B and C were isolated from the roots of Aconitum transsectum Diels, and their structures were elucidated by spectral means.

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UDT:U-shaped deformable transformer for subarachnoid haemorrhage image segmentation

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CAAI Transactions on Intelligence Technology 2024年第3期9卷 756-768页

作者： Wei Xie Lianghao Jin Shiqi Hua hao Sun Bo Sun Zhigang Tu Jun Liu Hubei Provincial Key Laboratory of Artificial Intelligence and Smart Learning Central China Normal UniversityWuhanChina School of Computer Science Central China Normal UniversityWuhanChina National Language Resources Monitoring and Research Center for Network Media Central China Normal UniversityWuhanChina The First Affiliated Hospital of Dalian Medical University DalianChina State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhanChina Information Systems Technology and Design Pillar Singapore University of Technology and DesignSingaporeSingapore

Subarachnoid haemorrhage(SAH),mostly caused by the rupture of intracranial aneu-rysm,is a common disease with a high fatality *** lesions are generally diffusely distributed,showing a variety of scales with irregular *** complex characteristics of lesions make SAH segmentation a challenging *** cope with these difficulties,a u-shaped deformable transformer(UDT)is proposed for SAH ***,first,a multi-scale deformable attention(MSDA)module is exploited to model the diffuseness and scale-variant characteristics of SAH lesions,where the MSDA module can fuse features in different scales and adjust the attention field of each element dynamically to generate discriminative multi-scale ***,the cross deformable attention-based skip connection(CDASC)module is designed to model the irregular edge char-acteristic of SAH lesions,where the CDASC module can utilise the spatial details from encoder features to refine the spatial information of decoder ***,the MSDA and CDASC modules are embedded into the backbone Res-UNet to construct the proposed *** experiments are conducted on the self-built SAH-CT dataset and two public medical datasets(GlaS and MoNuSeg).Experimental results show that the presented UDT achieves the state-of-the-art performance.

关键词： image segmentation medical image processing

Room-temperature ferromagnetism and piezoelectricity in metalfree 2D semiconductor crystalline carbon nitride

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Nano Research 2024年第6期17卷 5670-5679页

作者： Yong Wang Dingyi Yang Wei Xu Yongjie Xu Yu Zhang Zixuan Cheng Yizhang Wu Xuetao Gan Wei Zhong Yan Liu Genquan Han Yue hao Wide Bandgap Semiconductor Technology Disciplines State Key Laboratory School of MicroelectronicsAcademy of Advanced Interdisciplinary ResearchXidian UniversityXi’an 710071China Emerging Device and Chip Laboratory Hangzhou Institute of TechnologyXidian UniversityHangzhou 311200China INRS Centre for Energy Materials and Telecommunications1650 Boul.Lionel BouletVarennesQC J3X 1P7Canada National Laboratory of Solid State Microstructures Collaborative Innovation Center of Advanced Microstructures and Jiangsu Provincial Key Laboratory for NanotechnologyNanjing UniversityNanjing 210093China School of Education Jiangsu Open UniversityNanjing 210036China Department of Physics Shaanxi University of Science and TechnologyXi’an 710021China Department of Applied Physical Sciences The University of North Carolina at Chapel HillChapel HillNC 27514USA Key Laboratory of Light Field Manipulation and Information Acquisition Ministry of Industry and Information Technologyand Shaanxi Key Laboratory of Optical Information TechnologySchool of Physical Science and TechnologyNorthwestern Polytechnical UniversityXi'an 710129 China

Two-dimensional(2D)materials that combine ferromagnetic,semiconductor,and piezoelectric properties hold significant potential for both fundamental research and spin electronic ***,the majority of reported 2D ferromagnetic-semiconductor-piezoelectric materials rely on d-electron systems,which limits their practical applications due to a Curie temperature lower than room temperature(RT).Here,we report a high-crystallinity carbon nitride(CCN)material based on sp-electrons using a chemical vapor deposition *** exhibits a band gap of 1.8 eV and has been confirmed to possess substantial in-plane and out-of-plane ***,we acquired clear evidences of ferromagnetic behavior at room *** structural characterizations combined with theoretical calculations reveal that incorporating structural oxygen into the highly ordered heptazine structure causes partial substitution of nitrogen sites,which is primarily responsible for generating room-temperature ferromagnetism and *** a result,the strain in wrinkles can effectively modulate the domain behavior and piezoelectric potential at room *** addition of RT ferromagnetic-semiconductor-piezoelectric material based on sp-electrons to the family of two-dimensional materials opens up numerous possibilities for novel applications in fundamental research and spin electronic devices.

关键词： crystallinity carbon nitride room-temperature ferromagnetism piezoelectricity magnetic force microscopy density functional theory(DFT)calculations

Recent advances in Ir/Ru-based perovskite electrocatalysts for oxygen evolution reaction

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Rare Metals 2024年第7期43卷 2891-2912页

作者： Zhi-Qi Jiang Cheng-Zhen Fan Jun-Yu Pan Li Shao hao Chen Erum Pervaiz Yan Dong Tong-Zhou Wang Xue-Rong Zheng Ji-Hong Li Yi-Da Deng School of Materials Science and Engineering Hainan University Department of Chemical Engineering School of Chemical and Materials Engineering (SCME)National University of Sciences & Technology (NUST) Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) Nankai University

Oxygen evolution reaction(OER) is a kinetically harsh four-electron anode reaction that requires a large overpotential to provide current and is of great importance in renewable electrochemical ***/Rubased perovskite oxides hold great significance for application as OER electrocatalysts,due to that their multimetal-oxide forms can reduce the use of noble metals,and their compositional tunability can modulate the electronic structure and optimize OER ***,high operating potentials and corrosive environments pose a serious challenge to the development of durable Ir-based and Ru-based perovskite *** efforts have been dedicated to improving the Ir/Ru-based perovskite activity to enhance the efficiency;however,progress in improving the durability of Ir/Ru-based perovskite electrocatalysts has been rather *** this review,the recent research progress of Ir/Ru-based perovskites is reviewed from the perspective of heteroatom doping,structural modulation,and formation of *** dissolution mechanism studies of Ir/Ru and experimental attempts to improve the durability of Ir/Ru-based perovskite electrocatalysts are *** and outlooks for further developing Ru-and Irbased perovskite oxygen electrocatalysts are also presented.

关键词： Oxygen evolution reaction Ir/Ru-based perovskites Stability Electrocatalysts

Inducing mitochondriopathy-like damages by transformable nucleopeptide nanoparticles for targeted therapy of bladder cancer

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National Science Review 2024年第4期11卷 216-227页

作者： Da-Yong Hou Ni-Yuan Zhang Lu Wang Mei-Yu Lv Xiang-Peng Li Peng Zhang Yue-Ze Wang Lei Shen Xiu-Hai Wu Bo Fu Peng-Yu Guo Zi-Qi Wang Dong-Bing Cheng hao Wang Wanhai Xu NHC and CAMS Key Laboratory of Molecular Probe and Targeted Theranostics Heilongjiang Key Laboratory of Scientific Research in Urology Harbin Medical University Department of Urology Harbin Medical University Cancer Hospital CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety CAS Center for Excellence in NanoscienceNational Center for Nanoscience and Technology(NCNST) School of Chemistry Chemical Engineering & Life Science Hubei Key Laboratory of Nanomedicine for Neurodegenerative Diseases Wuhan University of Technology

Mitochondriopathy inspired adenosine triphosphate(ATP) depletions have been recognized as a powerful way for controlling tumor growth. Nevertheless, selective sequestration or exhaustion of ATP under complex biological environments remains a prodigious challenge. Harnessing the advantages of in vivo self-assembled nanomaterials, we designed an Intracellular ATP Sequestration(IAS) system to specifically construct nanofibrous nanostructures on the surface of tumor nuclei with exposed ATP binding sites,leading to highly efficient suppression of bladder cancer by induction of mitochondriopathy-like ***, the reported transformable nucleopeptide(NLS-FF-T) self-assembled into nuclear-targeted nanoparticles with ATP binding sites encapsulated inside under aqueous conditions. By interaction with KPNA2, the NLS-FF-T transformed into a nanofibrous-based ATP trapper on the surface of tumor nuclei,which prevented the production of intracellular energy. As a result, multiple bladder tumor cell lines(T24,EJ and RT-112) revealed that the half-maximal inhibitory concentration(IC50) of NLS-FF-T was reduced by approximately 4-fold when compared to NLS-T. Following intravenous administration, NLS-FF-T was found to be dose-dependently accumulated at the tumor site of T24 xenograft mice. More significantly, this IAS system exhibited an extremely antitumor efficacy according to the deterioration of T24 tumors and simultaneously prolonged the overall survival of T24 orthotopic xenograft mice. Together, our findings clearly demonstrated the therapeutic advantages of intracellular ATP sequestration-induced mitochondriopathy-like damages, which provides a potential treatment strategy for malignancies.

关键词： self-assembly nucleopeptide nanomaterial bladder cancer mitochondriopathy

Calculation of Phase Equilibria between Solid Solutions with Magnetic Transition by the Cluster Variation Method

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Journal of Materials Science & Technology 1997年第1期13卷 15-20页

作者： Liu, xj Jiang, M hao, SM Yuan, RW NE UNIV TECHNOL DEPT MAT SCI & ENGNSHENYANG 110006PEOPLES R CHINA

By using the geometric analysis of grand potential, the molar grand potential-effective chemical potential curve of solution with magnetic transition can be obtained from the relevant molar free energy diagram, and it is shown that the grand potential and effective chemical potential can be separated into paramagnetic and magnetic terms. In addition, the CVM has been combined with the present magnetic transition free energy model such as M. Hillert and T. Nishizawa's models to calculate phase equilibria between solutions with magnetic transition, and this combined method has been applied to the alpha/gamma phase equilibrium in the Fe-Mn binary system and found to be feasible.

关键词： Iron alloys

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三维步态识别研究进展

中国图象图形学报 2024年第7期29卷 1921-1933页

作者：沈澍张文昊丁浩张浩沙超王森陈书军南京邮电大学计算机学院南京210023 江苏警官学院刑事科学技术系南京210031 南京工业大学机械与动力工程学院南京211800

步态识别在身份识别领域具有重要的研究意义。随着技术的发展,步态识别的研究热点正从二维(2D)转向三维(3D)。与图像固有的2D信息相比,用视觉技术还原的3D信息能更有效地预测人员的身份。在2D视觉领域中,由于受到物体遮挡、视角变化等... 详细信息

步态识别在身份识别领域具有重要的研究意义。随着技术的发展,步态识别的研究热点正从二维(2D)转向三维(3D)。与图像固有的2D信息相比,用视觉技术还原的3D信息能更有效地预测人员的身份。在2D视觉领域中,由于受到物体遮挡、视角变化等因素的影响,传统的步态识别方法在实际应用中难以取得理想的识别性能。基于人体3D重建和人体3D姿态估计等3D人体技术,近年来的研究在3D步态识别领域取得了一系列进展。本文介绍了3D步态识别方法,探讨了基于3D步态的身份识别领域的研究现状、优势与不足;总结了主要的3D步态数据集;讨论了3D识别方法与2D识别方法的对比;提出了3D身份识别领域未来潜在的研究方向,包括3D数据集的采集和整理、2D和3D数据的多模态融合等。

关键词：计算机视觉生物特征识别步态识别三维人体身份识别三维建模