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Dcalycinumines A-E,Alkaloids with Cytotoxic Activities of Nasopharyngeal Carcinoma Cells from Daphniphyllum calycinum

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Chinese Journal of Chemistry 2024年第1期42卷 35-42页

作者： qing tang Xiao-Yong Dai Qiang Lin Zhi-Peng Ling Yi-Kun Hao Tian-Xi Zhu Ji-Hui Zhang Yi-Bo Hou Yao-Lan Li Lai-Qiang Huang Jing-Hao Wang Guo-Cai Wang Yu-Bo Zhang Guangdong Clinical Translational Centerfor Targeted Drug Department of PharmacologySchoolof MedicineJinan University GuangzhouGuangdong 510632China Institute of Traditional Chinese Medicine&Natural Products Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs ResearchCollegeof PharmacyJinan UniversityGuangzhouGuangdong511443China Institute of Biopharmaceutical and Health Engineering Shenzhen Key Laboratory of Gene and Antibody TherapyState Key Laboratory of Chemical OncogenomicsShenzhen International Graduate SchoolTsinghua UniversityShenzhenGuangdong 518055China The Guangzhou Key Laboratoryof Basic and Translational Research on Chronic Disease Department of PharmacyThe First Affiliated HospitalJinan UniversityGuangzhouGuangdong 510630China

Fivenovel Daphniphyllum alkaloids,named dcalycinumines A-E(1-4,6),andeight previously described Daphniphyllum alkaloids(5,7-13)were isolated from Daphniphyllum calycinum.Compound 1 is the first Daphniphyllum alkaloid possessing a highly rearranged 6/6/6/7/5/6 hexacyclic architecture with a unique 3-methyl-1-azabicyclo[4,4,0]decane ring system.Compound 2 represents a rare diamino Daphniphyllum alkaloid with an unprecedented 6/5/5/6/6/5 carbon skeleton featuring a unique 1-aza-6-azaspiro[4,5]decane unit,whereas 3 also represents a rare diamino Daphniphyllum alkaloid as a possible precursor of 2.Compound 4 is the second example of c-22-nor yuzurimine-type alkaloids.Their structures and absolute configurations were elucidated by HRESIMS,NMR spectroscopic analyses,EcD calculations,and single-crystal X-ray diffraction.Moreover,compound 1 showed remarkable antitumor activities,which could inhibit the proliferation,migration and invasion of nasopharyngeal carcinoma cells,and promoted nasopharyngeal carcinoma cells apoptosis.

关键词： Daphniphyllum calycinum Natural products Daphniphyllum alkaloid Structural elucidation Biological activity Apoptosis Nasopharyngealcarcinoma

Hyperbolic tangent Function-Based Protocols for Global/Semi-Global Finite-Time Consensus of Multi-Agent Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1381-1397页

作者： Zongyu Zuo Jingchuan tang Ruiqi Ke qing-Long Han Seventh Research Division Beihang University(BUAA)Beijing 100191China School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourne VIC 3122Australia IEEE

This paper investigates the problem of global/semi-global finite-time consensus for integrator-type multi-agent sys-tems.New hyperbolic tangent function-based protocols are pro-posed to achieve global and semi-global finite-time consensus for both single-integrator and double-integrator multi-agent systems with leaderless undirected and leader-following directed commu-nication topologies.These new protocols not only provide an explicit upper-bound estimate for the settling time,but also have a user-prescribed bounded control level.In addition,compared to some existing results based on the saturation function,the pro-posed approach considerably simplifies the protocol design and the stability analysis.Illustrative examples and an application demonstrate the effectiveness of the proposed protocols.

关键词： Consensus protocol finite-time consensus hyper-bolic tangent function multi-agent systems.

Applications of deep learning for detecting ophthalmic diseases with ultrawide-field fundus

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International Journal of Ophthalmology(English edition) 2024年第1期17卷 188-200页

作者： qing-qing tang Xiang-Gang Yang Hong-Qiu Wang Da-Wen Wu Mei-Xia Zhang Department of Ophthalmology and Research Laboratory of Macular Disease West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Hong Kong University of Science and Technology(Guangzhou) Guangzhou 511400Guangdong ProvinceChina

AIM:To summarize the application of deep learning in detecting ophthalmic disease with ultrawide-field fundus images and analyze the advantages,limitations,and possible solutions common to all tasks.METHODS:We searched three academic databases,including PubMed,Web of Science,and Ovid,with the date of August 2022.We matched and screened according to the target keywords and publication year and retrieved a total of 4358 research papers according to the keywords,of which 23 studies were retrieved on applying deep learning in diagnosing ophthalmic disease with ultrawide-field images.RESULTS:Deep learning in ultrawide-field images can detect various ophthalmic diseases and achieve great performance,including diabetic retinopathy,glaucoma,age-related macular degeneration,retinal vein occlusions,retinal detachment,and other peripheral retinal diseases.Compared to fundus images,the ultrawide-field fundus scanning laser ophthalmoscopy enables the capture of the ocular fundus up to 200°in a single exposure,which can observe more areas of the retina.CONCLUSION:The combination of ultrawide-field fundus images and artificial intelligence will achieve great performance in diagnosing multiple ophthalmic diseases in the future.

关键词： ultrawide-field fundus images deep learning disease diagnosis ophthalmic disease

Selective extinction and habitat nestedness are the main drivers of lizard nestedness in the Zhoushan Archipelago

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Current Zoology 2024年第2期70卷 244-252页

作者： Minchu Zhang Chaonan tang qing Zhang Chengxiu Zhan Chuanwu Chen Yanping Wang Laboratory of Island Biogeography and Conservation Biology College of Life SciencesNanjing Normal UniversityNanjing 210023China

Nested subset pattern(nestedness)is an important part of the theoretical framework of island biogeography and community ecology.However,most previous studies often used nestedness metrics or randomization algorithms that are vulnerable to type I error.In this study,we inves-tigated the nestedness of lizard assemblages on 37 islands in the Zhoushan Archipelago,China.We used the line-transect method to survey species occurrence,abundance,and habitat types of lizards on 37 islands during 2 breeding seasons in 2021 and 2022.We applied the nested metric WNODF and the conservative rc null model to control for type I error and quantify the significance of nestedness.Spearman rank cor relations were used to evaluate the role of 4 habitat variables(island area,2 isolation indices,and habitat diversity)and 4 ecological traits(body size,geographic range size,clutch size,and minimum area requirement)in generating nestedness.The results of WNODF analyses showed that lizard assemblages were significantly nested.The habitat-by-site matrix estimated by the program NODF was also significantly nested,support-ing the habitat nestedness hypothesis.The nestedness of lizard assemblages were significantly correlated with island area,habitat diversity.clutch size,and minimum area requirement.Overall,our results suggest that selective extinction and habitat nestedness were the main drivers of lizard nestedness in our system.In contrast,the nestedness of lizard assemblages was not due to passive sampling or selective colonization.To maximize the number of species preserved,our results indicate that we should protect both large islands with diverse habitats and species with largearea requirement and clutch size.

关键词： clutch size habitat nestedness lizards minimum area requirement nestedness selective extinction WNODF Zhoushan Archipelago.

Morphology Study for GeV Emission of Nearby Supernova Remnant G332.5-5.6

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Research in Astronomy and Astrophysics 2024年第4期24卷 134-140页

作者： Ming-Hong Luo qing-Wen tang Xiu-Rong Mo Department of Physics School of Physics and Materials ScienceNanchang UniversityNanchang 330031China

A spatial template is important to study nearby supernova remnants(SNRs).For SNR G332.5-5.6,we report a Gaussian disk with a radius of about 1°.06 to be a potential good spatial model in the γ-ray band.Employing this new Gaussian disk,its GeV lightcurve shows a significant variability of about seven sigma.The γ-ray observations of this SNR could be explained well either by a leptonic model or a hadronic model,in which a flat spectrum for the ejected electrons/protons is required.

关键词： ISM:supernova remnants gamma rays:ISM

Cascaded ELM-Based Joint Frame Synchronization and Channel Estimation over Rician Fading Channel with Hardware Imperfections

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China Communications 2024年第6期21卷 87-102页

作者： qing Chaojin Rao Chuangui Yang Na tang Shuhai Wang Jiafan School of Electrical Engineering and Electronic Information Xihua UniversityChengdu 610039China

Due to the interdependency of frame synchronization(FS)and channel estimation(CE),joint FS and CE(JFSCE)schemes are proposed to enhance their functionalities and therefore boost the overall performance of wireless communication systems.Although traditional JFSCE schemes alleviate the influence between FS and CE,they show deficiencies in dealing with hardware imperfection(HI)and deterministic line-of-sight(LOS)path.To tackle this challenge,we proposed a cascaded ELM-based JFSCE to alleviate the influence of HI in the scenario of the Rician fading channel.Specifically,the conventional JFSCE method is first employed to extract the initial features,and thus forms the non-Neural Network(NN)solutions for FS and CE,respectively.Then,the ELMbased networks,named FS-NET and CE-NET,are cascaded to capture the NN solutions of FS and CE.Simulation and analysis results show that,compared with the conventional JFSCE methods,the proposed cascaded ELM-based JFSCE significantly reduces the error probability of FS and the normalized mean square error(NMSE)of CE,even against the impacts of parameter variations.

关键词： channel estimation extreme learning machine frame synchronization hardware imperfection nonlinear distortion synchronization metric

Wide‑field swept‑source OCT angiography of the periarterial capillary‑free zone before and after anti‑VEGF therapy for branch retinal vein occlusion

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Eye and Vision 2024年第2期10卷 31-40页

作者： Wenyi tang Wei Liu Jingli Guo Lili Zhang Gezhi Xu Keyan Wang qing Chang Department of Ophthalmology Eye and ENT Hospital of Fudan University83 Fenyang RoadShanghai 200031China Shanghai Key Laboratory of Visual Impairment and Restoration Fudan UniversityShanghaiChina NHC Key Laboratory of Myopia(Fudan University) Laboratory of MyopiaChinese Academy of Medical SciencesShanghaiChina

Background:The aim of the study was to investigate the changes in the periarterial capillary-free zone(paCFZ)after anti-vascular endothelial growth factor(VEGF)therapy in patients with branch retinal vein occlusion(BRVO)by widefield swept-source optical coherence tomography angiography(SS-OCTA)and assess their associations with clinical outcomes.Methods:In this retrospective observational study of 54 treatment-naive BRVO patients with macular edema,we reviewed the findings of 12×12 mm^(2)SS-OCTA at baseline,3,6,and 12 months after intravitreal ranibizumab injections.The paCFZ and major retinal artery areas were measured on SS-OCTA images.The paCFZ area to artery area(P/A)ratio was calculated.Results:The paCFZ areas and P/A ratios of first-and second-order arteries were significantly greater in BRVO eyes than in contralateral eyes(all P<0.01),but there were no differences in the first-and second-order artery areas(P=0.20 and 0.25,respectively).The paCFZ areas and P/A ratios decreased significantly at 3,6,and 12 months after anti-VEGF therapy(all P<0.01).The baseline P/A ratio was significantly correlated with the baseline best-corrected visual acuity(BCVA),central retinal thickness,and their improvements at 3,6,and 12 months(all P<0.05).Baseline BCVA and P/A ratios of first-and second-order arteries were independently associated with the final BCVA in multivariate linear regression.Conclusions:Wide-field SS-OCTA shows that anti-VEGF therapy can lead to a significant improvement in the paCFZ parameters in BRVO.Smaller baseline P/A ratios on SS-OCTA tend to predict better visual outcomes at 12 months after anti-VEGF therapy.

关键词： Swept-source optical coherence tomography angiography Branch retinal vein occlusion Periarterial capillary free zone Anti-VEGF treatment Prognosis

Visual Semantic Segmentation Based on Few/Zero-Shot Learning:An Overview

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1106-1126页

作者： Wenqi Ren Yang tang Qiyu Sun Chaoqiang Zhao qing-Long Han Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghai 200237China National Key Laboratory of Air-Based Information Perception and Fusion Aviation Industry Corporation of ChinaLuoyang 471000China School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourne VIC 3122Australia

Visual semantic segmentation aims at separating a visual sample into diverse blocks with specific semantic attributes and identifying the category for each block,and it plays a crucial role in environmental perception.Conventional learning-based visual semantic segmentation approaches count heavily on largescale training data with dense annotations and consistently fail to estimate accurate semantic labels for unseen categories.This obstruction spurs a craze for studying visual semantic segmentation with the assistance of few/zero-shot learning.The emergence and rapid progress of few/zero-shot visual semantic segmentation make it possible to learn unseen categories from a few labeled or even zero-labeled samples,which advances the extension to practical applications.Therefore,this paper focuses on the recently published few/zero-shot visual semantic segmentation methods varying from 2D to 3D space and explores the commonalities and discrepancies of technical settlements under different segmentation circumstances.Specifically,the preliminaries on few/zeroshot visual semantic segmentation,including the problem definitions,typical datasets,and technical remedies,are briefly reviewed and discussed.Moreover,three typical instantiations are involved to uncover the interactions of few/zero-shot learning with visual semantic segmentation,including image semantic segmentation,video object segmentation,and 3D segmentation.Finally,the future challenges of few/zero-shot visual semantic segmentation are discussed.

关键词： Visual segmentation separating

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P-and SV-wave dispersion and attenuation in saturated microcracked porous rock with aligned penny-shaped fractures

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Petroleum Science 2024年第1期21卷 143-161页

作者： Sheng-qing Li Wen-Hao Wang Yuan-Da Su Jun-Xin Guo Xiao-Ming tang School of Geosciences China University of Petroleum(East China)Qingdao 266580ShandongChina Laoshan National Laboratory Qingdao 266071ShangdongChina Guangdong Provincial Key Laboratory of Geophysical High-resolution Imaging Technology Southern University of Science and TechnologyShenzhen 518055GuangdongChina Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen 518055GuangdongChina

P-and SV-wave dispersion and attenuation have been extensively investigated in saturated poroelastic media with aligned fractures.However,there are few existing models that incorporate the multiple wave attenuation mechanisms from the microscopic scale to the macroscopic scale.Hence,in this work,we developed a unified model to incorporate the wave attenuation mechanisms at different scales,which includes the microscopic squirt flow between the microcracks and pores,the mesoscopic wave-induced fluid flow between fractures and background(FB-WIFF),and the macroscopic Biot's global flow and elastic scattering(ES)from the fractures.Using tang's modified Biot's theory and the mixed-boundary conditions,we derived the exact frequency-dependent solutions of the scattering problem for a single penny-shaped fracture with oblique incident P-and SV-waves.We then developed theoretical models for a set of aligned fractures and randomly oriented fractures using the Foldy approximation.The results indicated that microcrack squirt flow considerably influences the dispersion and attenuation of P-and SV-wave velocities.The coupling effects of microcrack squirt flow with the FB-WIFF and ES of fractures cause much higher velocity dispersion and attenuation for P waves than for SV waves.Randomly oriented fractures substantially reduce the attenuation caused by the FB-WIFF and ES,particularly for the ES attenuation of SV waves.Through a comparison with existing models in the limiting cases and previous experimental measurements,we validated our model.

关键词： Aligned fractures P-and SV-wave Dispersion and attenuation Microcracked porous background FB-WIFF Elastic scattering Squirt flow