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Science China Chemistry 2024年第2期67卷 576-586页

作者： Xiao-Bao Wu Jun-Xiu shi Yi-ming Ou Hua-Jie Jiang Yi-Jun Fang Qi-ming Wang Quan gao Jie Yu Department of Applied Chemistry Anhui Province Engineering Laboratory for Green Pesticide Development and ApplicationAnhui Province Key Laboratory of Crop Integrated Pest ManagementAnhui Agricultural UniversityHefei230036China

A privileged strategy has been developed for the precise construction of enantioenriched azaspiro polycyclic *** diverse azaspiro polycycles bearing multiple contiguous stereocenters are obtained with excellent results(up to 99:1 e.r.,>95:5 d.r.) via sequential enantioselective four-component Ugi reactions/post-Ugi transformations with substrates containing prerequisite functional groups in the presence of anionic stereogenic-at-cobalt(Ⅲ) complexes.

关键词： asymmetric catalysis post-Ugi transformation anionic stereogenic-at-cobalt(Ⅲ)complex azaspiro polycyclic scaffold one-pot synthesis

An Improved Thermal Conductivity Measurement Scheme for Macroscopic Graphitic Films Using the Laser Flash Method

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Journal of Thermal Science 2024年第4期33卷 1480-1490页

作者： ZHANG Peijuan ming Xin LIU Yingjun WANG Xuelong shi Hang HAO Yuanyuan LU Jiahao LIU Zheng LAI Haiwen ZHANG Ying gao Weiwei XU Zhen gao Chao MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringKey Laboratory of Adsorption and Separation Materials&Technologies of Zhejiang ProvinceZhejiang UniversityHangzhou310027China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan030032China Special Equipment Safety Supervision and Inspection Institute of Jiangsu Province National Graphene Products Quality Inspection and Testing Center(Jiangsu)Wuxi214174China Hangzhou gaoxi Technol Co. LtdHangzhou311113China China Academy of Aerospace Aerodynamics Beijing100074China

Achieving efficient thermal management urges to exploit high-thermal-conductivity materials to satisfy the boosted demand of heat *** is critical to adopt standardized characterization protocols to evaluate the intrinsic thermal conductivity of thermal management ***,for the most representative laser flash method,the lack of standard measurement methodology and systematic description on the thermal diffusivity and influencing factors has led to significant deviations and confusion of the thermal conduction performance in the emerging thermal management ***,the measurement error factors of thermal diffusivity by the common laser flash analyzer(LFA)are *** high-thermal-conductivity graphitic film(GF)as a typical case,the key factors are analyzed to guide the measurement protocol of related carbon-based thermal management *** basic principle of the LFA measurement,actual pre-processing conditions,instrument parameters setting,and data analysis are elaborated for accurate ***,the graphene thick films and common isotropic materials are also extended to meet various thermal measurement *** on the existing practical problems,we propose a feasible test flow to achieve a unified and standardized thermal conductivity measurement,which is beneficial to the rapid development of carbon-based thermal management materials.

关键词： thermal management graphitic film laser flash method thermal conductivity thermal diffusivity

Spatial distribution of supra-permafrost groundwater in the Qinghai-Tibet Engineering Corridor using inversion models

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Advances in Climate Change Research 2024年第1期15卷 31-41页

作者： Yu gao ming-Tang CHAI Wei MA Yu-Tao gao State Key Laboratory of Frozen Soils Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 73000China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China School of Civil and Hydraulic Engineering Ningxia UniversityYinchuan 750021China

Supra-permafrost groundwater(SPG)is a key factor that causes damage to highways and railways in the Qinghai-Tibet Engineering Corridor(QTEC).It is difficult to monitor SPG in the field due to their complex formation mechanisms and movement *** single-site field monitoring studies limit the spatial and temporal precision of SPG spatial *** determine the moisture content of shallow soils and the SPG distribution along the QTEC,this work employed the temperature vegetation dryness index and remote sensing models for groundwater table distribution *** accuracies of the models were validated using mea-surements obtained from different sites in the *** the permafrost zones of the QTEC,72%,22%and 6%of the SPG were located at depths of 0.5-1,1 m,***,79.4%of the area along the Qinghai-Tibet Highway(QTH)(Xidatan-Tanggula)section contained *** these sections with SPG,37.9%have an SPG table at depths of 0.5-0.8 *** study preliminarily explored the SPG distribution in the QTEC with a 30 m *** findings can help improve the spatial scale of SPG research,provide a basis for the analysis of the hydrothermal mechanisms,and serve as a guide in the assessment of operational risks and road structure designs.

关键词： Dryness index Landsat Soil moisture Groundwater level Qinghai-Tibet Engineering Corridor

Generating diverse clothed 3D human animations via a generative model

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Computational Visual Media 2024年第2期10卷 261-277页

作者： Min shi Wenke Feng Lin gao Dengming Zhu School of Control and Computer Engineering North China Electric Power UniversityBeijing 102206China Institute of Computing Technology Chinese Academy of SciencesBeijing 100190China

Data-driven garment animation is a current topic of interest in the computer graphics *** approaches generally establish the mapping between a single human pose or a temporal pose sequence,and garment deformation,but it is difficult to quickly generate diverse clothed human *** address this problem with a method to automatically synthesize dressed human animations with temporal consistency from a specified human motion *** the heart of our method is a twostage ***,we first learn a latent space encoding the sequence-level distribution of human motions utilizing a transformer-based conditional variational autoencoder(Transformer-CVAE).Then a garment simulator synthesizes dynamic garment shapes using a transformer encoder-decoder *** the learned latent space comes from varied human motions,our method can generate a variety of styles of motions given a specific motion *** means of a novel beginning of sequence(BOS)learning strategy and a self-supervised refinement procedure,our garment simulator is capable of efficiently synthesizing garment deformation sequences corresponding to the generated human motions while maintaining temporal and spatial *** verify our ideas *** is the first generative model that directly dresses human animation.

关键词： Transformer garment animation conditional variational autoencoder(CVAE) computer graphics

HepG2.2.15-derived exosomes facilitate the activation and fibrosis of hepatic stellate cells

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World Journal of Gastroenterology 2024年第19期30卷 2553-2563页

作者： Yang gao Li Li Sheng-Ning Zhang Yuan-Yi Mang Xi-Bing Zhang shi-ming Feng Department of Hepatobiliary Pancreatic and Vascular Surgery The Affiliated Calmette Hospital of Kunming Medical University and The First Hospital of KunmingKunming 650011Yunnan ProvinceChina

BACKGROUND The role of exosomes derived from HepG2.2.15 cells,which express hepatitis B virus(HBV)-related proteins,in triggering the activation of LX2 liver stellate cells and promoting liver fibrosis and cell proliferation remains *** focus was on comprehending the relationship and influence of differentially expressed microRNAs(DE-miRNAs)within these *** To elucidate the effect of exosomes derived from HepG2.2.15 cells on the activation of hepatic stellate cell(HSC)LX2 and the progression of liver *** Exosomes from HepG2.2.15 cells,which express HBV-related proteins,were isolated from parental HepG2 and WRL68 *** blotting was used to confirm the presence of the exosomal marker protein *** activation of HSCs was assessed using oil red staining,whereas DiI staining facilitated the observation of exosomal uptake by LX2 ***,we evaluated LX2 cell proliferation and fibrosis marker expression using 5-ethynyl-2′-deoxyuracil staining and western blotting,***-miRNAs were analyzed using *** Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathways were used to annotate the target genes of *** Exosomes from HepG2.2.15 cells were found to induced activation and enhanced proliferation and fibrosis in LX2 cells.A total of 27 miRNAs were differentially expressed in exosomes from HepG2.2.15 *** analysis indicated that these DE-miRNA target genes were associated with cell differentiation,intracellular signal transduction,negative regulation of apoptosis,extracellular exosomes,and RNA *** pathway analysis highlighted ubiquitin-mediated proteolysis,the MAPK signaling pathway,viral carcinogenesis,and the toll-like receptor signaling pathway,among others,as enriched in these *** These findings suggest that exosomes from HepG2.2.15 cells play a substantial role in the activation,proliferation,and fibrosis of LX2 cells and that DE-miRNAs within these exos

关键词： Hepatic stellate cells Liver fibrosis Exosomes Small RNA sequencing HepG2.2.15

Dopamine Switches Affective States Under Acute Sleep Deprivation

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Neuroscience Bulletin 2024年第8期40卷 1205-1208页

作者： Zhou-Cai Luo Tian-ming gao State Key Laboratory of Organ Failure Research Key Laboratory of Mental Health of the Ministry of EducationGuangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired IntelligenceGuangdong-Hong Kong Joint Laboratory for Psychiatric DisordersGuangdong Province Key Laboratory of Psychiatric DisordersGuangdong Basic Research Center of Excellence for Integrated Traditional and Western Medicine for Qingzhi DiseasesDepartment of NeurobiologySchool of Basic Medical SciencesSouthern Medical UniversityGuangzhou 510515China

The transition of affective states manifests affective regulation,wherein individuals adaptively adjust their emotional states to cope with changes in the external environment,reflecting their sensitivity and adaptability to environmental *** process of affective state transition is complex,involving both instantaneous and persistent changes influenced by environmental,behavioral,and pharmacological *** underlying neural mechanisms encompass alterations in neurotransmitter release,neural circuit activity,and the plasticity of brain structures[1].

关键词： alterations Dopamine neural

Electromagnetic characteristic analysis and design of a linear motor used for ultra-high-speed EMS maglev train

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Science China(Technological Sciences) 2024年第6期67卷 1957-1973页

作者： gao Han shi TingNa gao XinMai LEI YanXiao YAN Dong GUO LiYan YAN Yan College of Electrical Engineering Zhejiang UniversityHangzhou310027China Zhejiang University Advanced Electrical Equipment Innovation Center Hangzhou311107China State Key Laboratory of High-speed Maglev Transportation Technology Qingdao266100China CRRC Qingdao Sifang Co.Ltd. Qingdao266111China

The operating speed of the commercial electromagnetic suspension(EMS)maglev train has been over 430 km/h,making it the fastest means of land *** the increasing demands of people traveling,it is necessary to further improve the operating speed of maglev *** to examine whether the existing EMS system can meet the requirements of ultra-highspeed operation(more than 600 km/h),the electromagnetic characteristics of an EMS linear motor under the operating speed of 600–1000 km/h fed by a square-wave voltage supply is investigated in this ***,an electromagnetic field model of the EMS system under the square-wave voltage supply is established to investigate its electromagnetic performance,e.g.,the characteristics of phase current,the magnetic flux density,and the electromagnetic ***,the relationship between the harmonic components of the air-gap magnetic flux density and electromagnetic force is investigated using the two-dimensional fast Fourier transform(2D-FFT)to reveal the mechanism of electromagnetic force ***,to address the issues of excessive armature current density and significant electromagnetic force ripple,the linear motor is re-designed by enlarging the stator slot area and reshaping the mover's main magnetic ***,the Taguchi method is used to further improve the electromagnetic characteristics of the linear electric ***,the effectiveness of the proposed optimal design is validated by the finite-element analysis(FEA)based co-simulation.

关键词： ultra-high-speed maglev transportation electromagnetic suspension(EMS) linear motor electromagnetic force ripple suppression

Synergistic effect of Zr and Mo on precipitation and high-temperature properties of Al-Si-Cu-Mg alloys

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China Foundry 2024年第1期21卷 71-81页

作者： Chao gao Bing-rong Zhang Yin-ming Li Zhi-ming Wang Xiang-bin Meng Faculty of Mechanical Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China Hebei Ounai Machinery Mould Co.Ltd. Xingtai 054500HebeiChina

This study focuses on finding a solution to the sharp decline in mechanical properties of Al-Si-Cu-Mg alloys due to rapid coarsening of traditional intermediate phases at high temperature.A new type of modified al oy,to be used in automobile engines at high temperatures,was prepared by adding Zr and Mo into Al-Si-Cu-Mg *** synergistic effects of Zr and Mo on the microstructure evolution and high-temperature mechanical properties were *** show that the addition of Zr and Mo generates a series of intermetallic phases dispersed in the *** can improve the strength of the alloy by hindering dislocation movement and crack *** addition,some nano-strengthened phases show coherent interfaces with the matrix and improve grain *** addition of Mo greatly improves the heat resistance of the *** extremely low diffusivity of Mo enables it to improve the thermal stability of the intermetallic phases,inhibit precipitation during aging,reduce the size of the precipitates,and improve the heat resistance of the alloy.

关键词： Al-Si-Cu-Mg alloy high-temperature properties Zr-Mo-rich intermetallics nano-strengthening phases

The Variation of Plankton Community Structure in Artificial Reef Area and Adjacent Waters in Haizhou Bay

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Journal of Ocean University of China 2024年第1期23卷 264-276页

作者： gao shike shi Yixi LU Yanan ZHANG Shuo College of Marine Sciences Shanghai Ocean UniversityShanghai 201306China Joint Laboratory for Monitoring and Conservation of Aquatic Living Resources in the Yangtze Estuary Shanghai 200000China

Plankton are an important component of marine protected areas(MPAs),and its communities would require much smaller interpatch distances to ensure connection among *** to the survey from MPAs dominated by artificial reefs and adjacent waters(estuary area(EA),aquaculture area(AA),artificial reef area(ARA),natural area(NA)and comprehensive effect area(CEA))in Haizhou Bay in spring and autumn,we analyzed phyto-zooplankton composition,abundance and biomass,and correlation with hydrologic variables to gain information about the forces that structure the *** results showed that the dominant zooplankton were copepods(spring,98.9%;autumn,94.2%),while the phytoplankton were mainly composed of Bacillariophyta(spring,61.8%;autumn,95.6%).The RDA results showed that temperature,salinity and depth highly associated with the distribution and composition of plankton species among the habitats than other factors in spring;temperature,Chla and DO had the strongest influence in *** zooplankton in the ARA and AA ecosystems basically contained the same species as those in other habitats,and each habitat also exhibited a relatively unique combination of plankton *** structures of the EA zooplankton in spring and the EA phytoplankton in both seasons were much different than other habitats,which may have been caused by factors such as currents and *** concluded that there exists similarity of the plankton community between artificial reef area and adjacent waters,whereas the EAs may be relatively independent ***,these interaction between plankton community should be considered when designing MPA networks,and ocean circulations should be considered more than the environmental factors.

关键词： zooplankton phytoplankton seasonal variation environmental factor artificial reef

LRChain:data protection and sharing method of learning archives based on consortium blockchain

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The Journal of China Universities of Posts and Telecommunications 2024年第4期31卷 28-42页

作者： Lan Lina gao Yuhan shi Ruisheng Wu Fenfen School of Humanities Beijing University of Posts and TelecommunicationsBeijing 100876China School of Cyberspace Security Beijing University of Posts and TelecommunicationsBeijing 100876China Key Laboratory of Trustworthy Distributed Computing and Service Beijing University of Posts and TelecommunicationsMinistry of EducationBeijing 100876China

Learning archives management in traditional systems faces challenges such as inadequate security,weak tamper resistance,and limited sharing *** address these issues,this paper proposes LRChain,a method based on consortium blockchain,for lifelong learning archives data protection and *** employs a combination of on-chain and off-chain cooperative storage using a consortium chain and inter planetary file system(IPFS)to enhance data security and *** also enables fine-grained verification of learning archives through selective disclosure principles,ensuring privacy protection of sensitive ***,an attributebased encryption(ABE)algorithm is utilized to establish authorized access control for learning archives,facilitating safe and trusted *** evaluations and security analyses demonstrate that this method exhibits decentralization,strong security,tamper resistance,and performs well,effectively meeting the requirements for secure sharing of learning archive data.

关键词： learning archives consortium blockchain collaborative storage secure sharing