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Chinese Chemical Letters 2000年第11期11卷 957-960页

作者： Su Yun LIU Dao Fei huang hai hong huang Liang huang Institute of Materia Medica Chinese Academy of Medical Science&Peking Union Medical CollegeBeijing 100050

(3R,5R)-3-((tert-Butyldimethylsily)oxy)-5-((Z)-2-bromovinyl)-tetrahydro-furan-2-one, an intermediate for the synthesis of Fostriecin was achieved by intramolecular asymmetric induction in propene addition of (-)-8-phenylmenthyl glyoxylate followed by inversion of C3-hydroxyl group and Sharpless asymmetric dihydroxylation with simultaneous cyclization to give lactone 5. Then protection of C3-hydroxyl group and oxidation of the C6-primary hydroxyl group which reacted with Wittig reagent to yield the target compound 4.

关键词： Fostriecin dihydroxylation (-)-8-phenylmenthol asymmetric synthes

An improved synthesis of(lS,4S)-2-oxa-5-azabicyclo[2.2.1]heptane

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Chinese Chemical Letters 2014年第3期25卷 479-481页

作者： Dong-Feng Zhang Peng Li Zi-Yun Lin hai-hong huang Beijing Key Laboratory of Active Substance Discovery and Druggability Evaluation Institute of Materia MedicaPeking Union Medical College & Chinese Academy of Medical Sciences

An improved and efficient method for synthesis of （1S,4S）-2-oxa-5-azabicyclo[2.2.1]heptane （1） from trans-4-hydroxy-L-proline was developed. Using benzyloxycarbonyl （Cbz） as protection group of amine, the reacti... 详细信息

关键词： Synthesistrans-4-Hydroxy-L-prolineBridged morpholine

A facile protocol for N-Cbz protection of amines in PEG-600

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Chinese Chemical Letters 2012年第7期23卷 789-792页

作者： Chun Lin Zhang Dong Feng Zhang hong Yi Zhao Zi Yun Lin hai hong huang Beijing Key Laboratory of Active Substance Discovery and Druggability Evaluation Institute of Materia MedicaPeking Union Medical College and Chinese Academy of Medical SciencesBeijing 100050China

An efficient and eco-friendly protocol for the chemoselective N-benzyloxycarbonylation of amines was *** reaction of amines with benzyl chloroformate（Cbz-Cl） in the presence of PEG-600 at room temperature afforded the corresponding N-Cbz derivatives in excellent *** method is applicable to the N-Cbz protection of aliphatic（acyclic and cyclic） and aromatic amines.

关键词： Benzyl chloroformate (Cbz-C1) N-Cbz protection Amines PEG-600

XGCN:a library for large-scale graph neural network recommendations

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Frontiers of Computer Science 2024年第3期18卷 247-249页

作者： Xiran SONG hong huang Jianxun LIAN hai JIN National Engineering Research Center for Big Data Technology and System Services Computing Technology and System LabCluster and Grid Computing LabSchool of Computer Science and TechnologyHuazhong University of Science and TechnologyWuhan 430074China Microsoft Research Asia Beijing 100080China

1 Introduction Graph Neural Networks(GNNs)have gained widespread adoption in recommendation systems,and nowadays there is a pressing need to effectively manage large-scale graph data[1].When it comes to large graphs,GNNs may encounter the scalability issue stemming from their multi-layer messagepassing ***,scaling GNNs has emerged as a crucial research area in recent years,with numerous scaling strategies being proposed.

关键词： scaling gained operations

Media Power Measuring via Emotional Contagion

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Journal of Social Computing 2024年第1期5卷 15-35页

作者： Xue Lin hong huang Zongya Li hai Jin National Engineering Research Center for Big Data Technology and System Services Computing Technology and System LabCluster and Grid Computing LabSchool of Computer Science and TechnologyHuazhong University of Science and TechnologyWuhan 430074China School of Journalism Huazhong University of Science and TechnologyWuhan 430074China

Media power,the impact that media have on public opinion and perspectives,plays a significant role in maintaining internal stability,exerting external influence,and shaping international dynamics for nations/***,prior research has primarily concentrated on news content and reporting time,resulting in limitations in evaluating media *** more accurately assess media power,we use news content,news reporting time,and news emotion simultaneously to explore the emotional contagion between *** use emotional contagion to measure the mutual influence between media and regard the media with greater impact as having stronger media *** propose a framework called Measuring Media Power via Emotional Contagion(MMPEC)to capture emotional contagion among media,enabling a more accurate assessment of media power at the media and national/regional *** also interprets experimental results through correlation and causality analyses,ensuring *** analyses confirm the higher accuracy of MMPEC compared to other baseline models,as demonstrated in the context of COVID-19-related news,yielding compelling and interesting insights.

关键词： explainability media power emotional contagion

Transient responses of double-curved sandwich two-layer shells resting on Kerr's foundations with laminated three-phase polymer/GNP/fiber surface and auxetic honeycomb core subjected to the blast load

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Defence Technology（防务技术） 2024年第5期35卷 222-247页

作者： Nguyen Thi hai Van Thi hong Nguyen Researcher&Lecturer Faculty of Industrial EducationThe University of Danang-University of Technology and Education48 Cao ThangDanang550000Viet Nam Researcher&Lecturer Faculty of Mechanical EngineeringThuyloi University175 Tay SonDong DaHanoi100000Viet Nam

This work uses refined first-order shear theory to analyze the free vibration and transient responses of double-curved sandwich two-layer shells made of auxetic honeycomb core and laminated three-phase polymer/GNP/fiber surface subjected to the blast *** of the two layers that make up the double-curved shell structure is made up of an auxetic honeycomb core and two laminated sheets of three-phase polymer/GNP/*** exterior is supported by a Kerr elastic foundation with three *** key innovation of the proposed theory is that the transverse shear stresses are zero at two free surfaces of each *** contrast to previous first-order shear deformation theories,no shear correction factor is ***'s exact solution was used to treat the double-curved shell problem with a single title boundary,while the finite element technique and an eight-node quadrilateral were used to address the other boundary *** ensure the accuracy of these results,a thorough comparison technique is employed in conjunction with credible *** problem model's edge cases allow for this kind of *** study's findings may be used in the post-construction evaluation of military and civil works structures for their ability to sustain explosive *** addition,this is also an important basis for the calculation and design of shell structures made of smart materials when subjected to shock waves or explosive loads.

关键词： Blast load Two-layer shell Polymer/GNP/Fiber surface Auxetic honeycomb Shear connectors

Three-dimensional choroidal vascularity index and choroidal thickness in fellow eyes of acute and chronic primary angle-closure using swept-source optical coherence tomography

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International Journal of Ophthalmology(English edition) 2024年第1期17卷 42-52页

作者： hai-Li huang Guan-hong Wang Liang-Liang Niu Xing-Huai Sun Department of Ophthalmology&Visual Science Eye&ENT HospitalShanghai Medical CollegeFudan UniversityShanghai 200031China State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science Institutes of Brain ScienceFudan UniversityShanghai 200032China NHC Key Laboratory of Myopia Chinese Academy of Medical Sciencesand Shanghai Key Laboratory of Visual Impairment and Restoration(Fudan University)Shanghai 200031China

AIM:To compare the three-dimensional choroidal vascularity index(CVI)and choroidal thickness between fellow eyes of acute primary angle-closure(F-APAC)and chronic primary angle-closure glaucoma(F-CPACG)and the eyes of normal ***:This study included 37 patients with unilateral APAC,37 with asymmetric CPACG without prior treatment,and 36 healthy *** swept-source optical coherence tomography(SS-OCT),the macular and peripapillary choroidal thickness and three-dimensional CVI were measured and compared globally and ***’s correlation analysis and multivariate regression models were used to evaluate choroidal thickness or CVI with related ***:The mean subfoveal CVIs were 0.35±0.10,0.33±0.09,and 0.29±0.04,and the mean subfoveal choroidal thickness were 315.62±52.92,306.22±59.29,and 262.69±45.55μm in the F-APAC,F-CPACG,and normal groups,*** macular sectors showed significantly higher CVIs and choroidal thickness in the F-APAC and F-CPACG eyes than in the normal eyes(P<0.05),while there were no significant differences between the F-APAC and F-CPACG *** the peripapillary region,the mean overall CVIs were 0.21±0.08,0.20±0.08,and 0.19±0.05,and the mean overall choroidal thickness were 180.45±54.18,174.82±50.67,and 176.18±37.94μm in the F-APAC,F-CPACG,and normal groups,*** were no significant differences between any of the two groups in all peripapillary *** age,shorter axial length,and the F-APAC or F-CPACG diagnosis were significantly associated with higher subfoveal CVI and thicker subfoveal choroidal thickness(P<0.05).CONCLUSION:The fellow eyes of unilateral APAC or asymmetric CPACG have higher macular CVI and choroidal thickness than those of the normal *** CVI nor choroidal thickness can distinguish between eyes predisposed to APAC or CPACG.A thicker choroid with a higher vascular volume may play a role in the pathogenesis of primary angle-closure glaucoma.

关键词： choroidal thickness choroidal vascularity index swept-source optical coherence tomography acute primary angle-closure chronic primary angle-closure glaucoma

Design,synthesis and primary activity of thiomorpholine derivatives as DPP-Ⅳinhibitors

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Chinese Chemical Letters 2012年第3期23卷 297-300页

作者： Bei Han Jing Long Liu Yi Huan Peng Li Qi Wu Zi Yun Lin Zhu Fang Shen Da Li Yin hai hong huang Beijing Key Laboratory of Active Substances Discovery and Druggability Evaluation Institute of Materia MedicaPeking Union Medical College&Chinese Academy of Medical SciencesBeijing 100050China

Thirteen thiomorpholine-bearing compounds were designed and synthesized as dipeptidyl peptidase IV（DPP-IV） inhibitors, with natural and non-natural L-amino acids as the starting *** structures were characterized by ~1H NMR,^（13）C NMR and *** target compounds were screened for the DPP-IV inhibition,and the preliminary SAR result was ***, compounds 4c,4d and 4f with good DPP-IV inhibition in vitro were further evaluated through a mouse oral glucose tolerance test （OGTT）.The preliminary result showed the potential value for further studies on those thiomorpholine-bearing compounds as DPP-IV inhibitors.

关键词： Thiomorpholine Dipeptidyl peptidaseⅣinhibitor Synthesis Structure-activity relationship Oral glucose tolerance test

Energy-information trade-off induces continuous and discontinuous phase transitions in lateral predictive coding

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 79-85页

作者： Zhen-Ye huang Ruyi Zhou Miao huang hai-Jun Zhou Key Laboratory for Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China School of Optics and Photonics Beijing Institute of TechnologyBeijing 100081China Minjiang Collaborative Center for Theoretical Physics Minjiang UniversityFuzhou 350108China

Lateral predictive coding is a recurrent neural network that creates energy-efficient internal representations by exploiting statistical regularity in sensory ***,we analytically investigate the trade-off between information robustness and energy in a linear model of lateral predictive coding and numerically minimize a free energy *** observed several phase transitions in the synaptic weight matrix,particularly a continuous transition that breaks reciprocity and permutation symmetry and builds cyclic dominance and a discontinuous transition with the associated sudden emergence of tight balance between excitatory and inhibitory *** optimal network follows an ideal gas law over an extended temperature range and saturates the efficiency upper bound of energy *** results provide theoretical insights into the emergence and evolution of complex internal models in predictive processing systems.

关键词： predictive coding recurrent neural network phase transition internal model free energy

Design optimization of a hexapod vibration isolation system for electro-optical payload

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Chinese Journal of Aeronautics 2024年第2期37卷 330-342页

作者： Jing LI Weipeng LI Xiaoyan ZHANG hai huang School of Astronautics Beihang UniversityBeijing 100191China

The electro-optical payloads on mobile platforms generally suffer undesirable vibrations generated by maneuvers and *** vibrations are in six degrees of freedom and cause line-of-sight jitters,resulting in image blurring and loss of tracking *** this paper,a Hexapod Vibration Isolation System(HVIS)is proposed and optimized to solve this *** optimization aims to centralize and minimize the natural frequencies of HVIS,for expanding the vibration isolation bandwidth and improving the vibration isolation in the higher frequency *** that the design space for HVIS is limited and interfered with the frames of the mobile platform,a non-collision algorithm is proposed and applied in the optimization to obtain the feasible optimal *** optimization result shows that the natural frequency bandwidth has been reduced by 42.9%,and the maximum natural frequency is reduced by 30.2%.The prototypes of initial and optimal designs are manufactured and *** simulated and experimental results demonstrate the validity of the optimization,and the optimal design provides a maximum of 15 dB more isolation in rotation direction than the initial design.

关键词： Electro-optical payload Vibrations Isolation system Hexapod Optimization Non-collision design