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Catalyst-Free Regio-and Diastereoselective Synthesis of Heterocyclic Nucleosides in the Eco-friendly Solvent 2-Methyltetrahydrofurant

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Chinese Journal of Chemistry 2023年第2期41卷 167-172页

作者： xiaodong gu Qingwei Du Weijian Song Jun(Joelle)Wang Department of Chemistry Hong Kong Baptist UniversityKowloonHong KongChina Department of Chemistry Southern University of Science and TechnologyShenzhenGuangdong 518055China

An efficient and practical synthesis of heterocyclic nucleosides is developed by a catalyst-free highly regioselective and diastereose-lective[3+2]annulation of a-purine-substituted acrylates with *** reaction operates with excellent functional group toler-ance,very mild reaction conditions,and with the green,sustainable,and eco-friendly 2-methyltetrahydrofuran(2-MeTHF)as *** with other reactions of electron-deficient olefin dipolarophiles with nitrones,different regioselective cycloaddition products were observed in this *** 1,3-dipolar cycloaddition reaction gives a series of isoxazolidinyl nucleosides in good to excellent yields with promising applications in biochemistry and medicinal chemistry.

关键词： Heterocycle Nucleoside Catalyst-free Annulation Regioselectivity Synthetic methods Cycloaddition

A MODEL-ORIENTED ROAD DETECTION APPROACH USING FUZZY SVM

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Journal of Electronics(China) 2010年第6期27卷 795-800页

作者： Zhang Yuying gu xiaodong Wang Yuanyuan Department of Electronic Engineering Fudan University Shanghai 200433 China

This paper presents an approach of model-oriented road detection based on trapezoidal model proposed by H. Jeong, et al and fuzzy Support Vector Machine (SVM). Firstly, the frames ex-tracted from the video are preprocessed by Pulse Coupled Neural Network (PCNN), and then handled by Kalman filter and Expectation Maximization (EM) algorithms. Next, according to the road's dif-ferent feathers, using fuzzy algorithm chooses a corresponding SVM for further lane detection, and then using morphological filters obtains the final detecting result. For different types of roads, this method uses fuzzy algorithm to choose different SVMs. Furthermore, in preprocessing using PCNN removes the shadow in the road to reduce the effect of illumination variations. Experimental results show that our method can receive better lane detecting results than the trapezoidal model and BP proposed by H. Jeong, et al..

关键词： Fuzzy Support Vector Machine (SVM) Kalman filter Model-oriented Lane detection Unstructured-road

Quantifying landscape linkages among giant panda subpopulations in regional scale conservation

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Integrative Zoology 2012年第2期7卷 165-174页

作者： Dunwu QI Yibo HU xiaodong gu Xuyi YANG guang YANG Fuwen WEI Jiangsu Key Laboratory for Biodiversity and Biotechnology College of Life SciencesNanjing Normal UniversityNanjingChina Key Laboratory for Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijingChina Wildlife Conservation Division Sichuan Forestry DepartmentChengduChina

Understanding habitat requirements and identifying landscape linkages are essential for the survival of isolated populations of endangered ***,some of the giant panda populations are isolated,which threatens their long-term survival,particularly in the Xiaoxiangling *** the present study,we quantified niche requirements and then identified potential linkages of giant panda subpopulations in the most isolated region,using ecological niche factor analysis and a least-cost path *** pandas preferred habitat with conifer forest and gentle slopes(>20 to≤30°).Based on spatial distribution of suitable habitat,linkages were identified for the Yele subpopulation to 4 other subpopulations(Liziping,Matou,Xinmin and Wanba).Their lengths ranged from 15 to 54 *** accumulated cost ranged from 693 to 3166 and conifer forest covered over 31%.However,a variety of features(*** roads,human settlements and large unforested areas)might act as barriers along the linkages for giant panda *** analysis quantified giant panda subpopulation connectivity to ensure long-term survival.

关键词： Ailuropoda melanoleuca ecological niche factor analysis giant panda landscape connectivity least-cost path analysis species conservation

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Journal of Geographical Sciences 2022年第4期32卷 589-604页

作者： FENG Huihui DING Ying ZOU Bin COHEN Jason Blake YE Shuchao YANG Zhuolin QIN Kai LIU Lei gu xiaodong School of Geosciences and Info-Physics Central South UniversityChangsha 410083China Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring of Chinese Ministry of Education Changsha 410083China School of Atmospheric Sciences Sun Yat-sen UniversityGuangzhou 510275China School of Environment Science and Spatial Informatics China University of Mining and TechnologyXuzhou 221116JiangsuChina College of Earth and Environmental Sciences Lanzhou UniversityLanzhou 730000China guangzhou Center for Rule of Green Development Law Studies Guangdong University of Foreign StudiesGuangzhou 510420China Southern Marine Science and Engineering guangdong Laboratory(guangzhou) Guangzhou 511458China

Vegetation plays an important role in the dry deposition of particles with significant spatial variability,but the magnitude remains unclear at the global *** the aid of satellite products,this study estimated the vegetation-related dry deposition of fine particulate matter(PM_(2.5)).Methodologically,dry deposition was first calculated using an empirical ***,deposition on the leaf surface was estimated to evaluate the influence of *** results showed that the mean deposition velocity(V_(d))of global PM_(2.5)was 0.91×10^(-3)μg·m^(-2)·s^(-1),with high velocities observed in sparsely vegetated regions because of the high friction *** the combined effect of the PM_(2.5)mass concentration and deposition velocity,the global mean dry deposition reached 0.47 g·m-^(2)·yr^(-1).Global vegetation absorbed 0.26 g·m-^(2)·yr^(-1)from PM_(2.5)pollution sources,contributing 54.98%of the total dry ***,vegetation-related dry deposition was high in the Amazon,Central Africa and East China due to dense vegetation coverage or serious ***,the increasing trends were mainly in Central Africa and India because of worsening air *** results of this study helped to clarify the impact of vegetation on air pollution,which supported related land management and planning for air quality improvement.

关键词： air pollution PM_(2.5) dry deposition vegetation change globe satellite

ThyroidNet:A Deep Learning Network for Localization and Classification of Thyroid Nodules

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 361-382页

作者： Lu Chen Huaqiang Chen Zhikai Pan Sheng Xu guangsheng Lai Shuwen Chen Shuihua Wang xiaodong gu Yudong Zhang Ultrasonic Department Zhongda Hospital Affiliated to Southeast UniversityNanjing210009China School of Physics and Information Engineering Jiangsu Second Normal UniversityNanjing211200China School of Computing and Mathematical Sciences University of LeicesterLeicesterLE17RHUK Department of Information Systems Faculty of Computing and Information TechnologyKing Abdulaziz UniversityJeddah21589Saudi Arabia State Key Laboratory of MillimeterWaves Southeast UniversityNanjing210096China Jiangsu Province Engineering Research Center of Basic Education Big Data Application Jiangsu Second Normal UniversityNanjing211200China School of Software Engineering Quanzhou Normal UniversityQuanzhou362000China Department of Biological Sciences Xi’an Jiaotong-Liverpool UniversitySuzhou215123China

Aim:This study aims to establish an artificial intelligence model,ThyroidNet,to diagnose thyroid nodules using deep learning techniques ***:A novel method,ThyroidNet,is introduced and evaluated based on deep learning for the localization and classification of thyroid ***,we propose the multitask TransUnet,which combines the TransUnet encoder and decoder with multitask ***,we propose the DualLoss function,tailored to the thyroid nodule localization and classification *** balances the learning of the localization and classification tasks to help improve the model’s generalization ***,we introduce strategies for augmenting the ***,we submit a novel deep learning model,ThyroidNet,to accurately detect thyroid ***:ThyroidNet was evaluated on private datasets and was comparable to other existing methods,including U-Net and *** results show that ThyroidNet outperformed these methods in localizing and classifying thyroid *** achieved improved accuracy of 3.9%and 1.5%,***:ThyroidNet significantly improves the clinical diagnosis of thyroid nodules and supports medical image analysis *** research directions include optimization of the model structure,expansion of the dataset size,reduction of computational complexity and memory requirements,and exploration of additional applications of ThyroidNet in medical image analysis.

关键词： ThyroidNet deep learning TransUnet multitask learning medical image analysis

Genome-wide signatures of mammalian skin covering evolution

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Science China(Life Sciences) 2021年第10期64卷 1765-1780页

作者： Peng Cao Qinlong Dai Cao Deng Xiang Zhao Shishan Qin Jian Yang Ran Ju Zhiwen Wang guoqing Lu xiaodong gu Zhisong Yang Lifeng Zhu Key Laboratory of Drug Targets and Drug Leads for Degenerative Diseases Affiliated Hospital of Integrated Traditional Chinese and Western MedicineNanjing University of Chinese MedicineNanjing 210023China College of Life Sciences Nanjing Normal UniversityNanjing 210046China University of Nebraska at Omaha Omaha 68181USA DNA Stories Bioinformatics Center Chengdu 610021China PubBio-Tech Services Corporation Wuhan 430070China Sichuan Station of Wildlife survey and Management Chengdu 610082China Nanjing Foreign Language School Xianlin Branch Nanjing 210023China Key Laboratory of Southwest China Wildlife Resources Conservation(Ministry of Education) China West Normal UniversityNanchong 637002China Shimian Research Center of Giant Panda Small Population Conservation and Rejuvenation Yaan 625400China Liziping Natural Reserve Yaan 625400China

Animal body coverings provide protection and allow for adaptation to environmental pressures such as heat,ultraviolet radiation,water loss,and mechanical ***,using a comparative genomics analysis of 39 mammal species spanning three skin covering types(hairless,scaly and spiny),we found some genes(e.g.,UVRAG,POLH,and XPC)involved in skin inflammation,skin innate immunity,and ultraviolet radiation damage repair were under selection in hairless ocean mammals(e.g.,whales and manatees).These signatures might be associated with a high risk of skin diseases from pathogens and ultraviolet ***,the genomes from three spiny mammal species shared convergent genomic regions(EPHB2,EPHA4,and NIN)and unique positively selected genes(FZD6,INVS,and CDC42)involved in skin cell polarity,which might be related to the development of *** scaly mammals,the shared convergent genomic regions(e.g.,FREM2)were associated with the integrity of the skin epithelium and epidermal *** study identifies potential convergent genomic features among distantly related mammals with the same skin covering type.

关键词： comparative genomics skin coverings spiny mammals hairless mammals scaly mammals convergent evolution

Need of a paradigm shift to conserve endangered species in China’s national park system

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The Innovation 2023年第4期4卷 23-24页

作者： Biao Yang Qiang Dai Yu Xu Christina D.Buesching xiaodong gu Zhisong Yang Zejun Zhang Fuwen Wei Key Laboratory of Southwest China Wildlife Resources Conservation(Ministry of Education) China West Normal UniversityNanchong 637002China College of Forestry Jiangxi Agricultural UniversityNanchang 330045China CAS Key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041China School of Life Sciences Guizhou Normal UniversityGuiyang 550001China Department of Biology The University of British ColumbiaKelownaBC V1V1V7Canada Giant Panda National Park Administration Chengdu 610081China Sichuan Academy of Giant Panda Chengdu 610081China

CHINAS EVOLVING NATIONAL PARK DESIGNATIONS AND SINGLE LARGE PROTECTED AREA OR SEVERAL SMALL PROTECTED AREAS(SLOSS)DEBATE As of 2021,the International Union for Conservation of Nature estimated that there are over 6,000 national parks(NPs)in more than 100 countries,most of which are strongly focused on endangered species.1 Over the past 6 years,China has invested US$20million in developing the Giant Panda National Park(GPNP)and a furtherUS$16million in establishing theNortheast China Tiger and Leopard National Park(NCTLNP).

关键词： invested PARK Northeast

Liposomes as versatile agents for the management of traumatic and nontraumatic central nervous system disorders:drug stability,targeting efficiency,and safety

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Neural Regeneration Research 2025年第7期20卷 1883-1899页

作者： Mingyu Zhang Chunyu Xiang Renrui Niu xiaodong He Wenqi Luo Wanguo Liu Rui gu Department of Orthopedic Surgery China-Japan Union Hospital of Jilin UniversityChangchunJilin ProvinceChina

Various nanoparticle-based drug delivery systems for the treatment of neurological disorders have been widely ***,their inability to cross the blood–brain barrier hampers the clinical translation of these therapeutic *** are nanoparticles composed of lipid bilayers,which can effectively encapsulate drugs and improve drug delivery across the blood–brain barrier and into brain tissue through their targeting and ***,they can potentially treat traumatic and nontraumatic central nervous system *** this review,we outlined the common properties and preparation methods of liposomes,including thin-film hydration,reverse-phase evaporation,solvent injection techniques,detergent removal methods,and microfluidics ***,we comprehensively discussed the current applications of liposomes in central nervous system diseases,such as Alzheimer's disease,Parkinson's disease,Huntington's disease,amyotrophic lateral sclerosis,traumatic brain injury,spinal cord injury,and brain *** studies related to liposomes are still in the laboratory stage and have not yet entered clinical ***,their application as drug delivery systems in clinical practice faces challenges such as drug stability,targeting efficiency,and ***,we proposed development strategies related to liposomes to further promote their development in neurological disease research.

关键词： Alzheimer's disease amyotrophic lateral sclerosis brain tumors central nervous system Huntington's disease liposome drug delivery neurological disorders Parkinson's disease spinal cord injury traumatic brain injury

Non-mechanical beam scanner based on VCSEL integrated amplifier with resonant wavelength detuning design

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Chinese Optics Letters 2021年第12期19卷 39-44页

作者： Shanting Hu xiaodong gu Masanori Nakahama Fumio Koyama Beijing University of Posts and Telecommunications Beijing 100876China Institute of Innovative Research(IIR) Tokyo Institute of Technology4259-R2-22 Nagatsuta-choMidori-kuYokohama 226-8503Japan Ambition Photonics Inc. Yokohama 226-8510Japan

We demonstrate the non-mechanical beam steering and amplifier operation of a vertical cavity surface emitting laser(VCSEL)integrated Bragg reflector waveguide amplifier with a cut-off wavelength detuning design,which enables unidirectional lateral coupling,continuous electrical beam steering,and diffraction-limited divergence *** present the modeling of the proposed structure for unidirectional coupling between a seed single-mode VCSEL and slow-light *** also present the detailed operating characteristics including the near-field and far-field patterns,light/current characteristics,and lasing *** experimental measurements exhibit a single-mode output of over 8 mW under CW operation,a continuous beam steering range of 16°,and beam divergence below 0.1°as an optical beam *** integrated amplifier length is as small as 0.9 mm,and thus we could expect much higher powers and higher resolution points by increasing the amplifier lengths.

关键词： VCSEL integrated amplifier unidirectional coupling optical beam scanner