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Spatial evolution and growth mechanism of urban networks in western China:A multi-scale perspective

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Journal of Geographical Sciences 2022年第3期32卷 517-536页

作者： yang Liangjie WANG Jing yang yongchun School of Geography and Environmental Sciences Northwest Normal UniversityLanzhou 730070China School of Resources and Environmental Lanzhou UniversityLanzhou 730070China

Globalization and informatization promote the evolution of urban spatial organization from a hierarchical structure mode to a network structure mode,forming a complex network *** study considers the coupling of“space of flows”and“spaces of places”as the core and“embeddedness”as the link and a relevant theoretical basis;then we construct a conceptual model of urban networks and explore the internal logic of enterprise networks and city *** the interlocking-affiliate network model and data from China’s top 500 listed companies,this study constructs a directed multi-valued relational matrix between cities in western China from 2005 to *** social network analysis and the multiple regression of quadratic assignment program model(MRQAP),this study adopts a“top-down”research perspective to analyze the spatio-temporal evolution and growth mechanism of the city network in western China from three nested spatial scales:large regions,intercity agglomerations,and intracity *** results show the following:(1)Under the large regional scale,the city network has good symmetry,obvious characteristics of hierarchical diffusion,neighborhood diffusion,and cross-administrative regional connection,presenting the“core-periphery”structural pattern.(2)The network of intercity agglomerations has the characteristics of centralization,stratification,and geographical proximity.(3)The internal network of each urban agglomeration presents a variety of network structure modes,such as dual-core,single-core,and multicore modes.(4)Administrative subordination and economic system proximity have a significant positive impact on the city network in western *** differences in internet convenience,investment in science and technology,average time distance,and economic development have negative effects on the growth and development of city networks.(5)The preferential attachment is the internal driving force of the city network development.

关键词： interlocking-affiliate network model urban agglomerations western China centrality multiple regression of quadratic assignment program(MRQAP)

Cross-border Urban Networks Based on Manufacturing Global Value Chain:A Study of Listed Companies in Western China

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Chinese Geographical Science 2023年第6期33卷 1033-1052页

作者： MAN Shan yang yongchun ZENG Tonggang WANG Meimei College of Earth and Environmental Sciences Lanzhou UniversityLanzhou730000China Key Laboratory of Western China’s Environmental Systems Ministry of Education of the People’s Republic of ChinaLanzhou UniversityLanzhou730000China

Cross-border investment is essential for western China’s *** value chain(GVC)forms cross-border investment networks between industries in western China and overseas *** on GVC,this study uses the social network analysis method,entropy method,multi-index comprehensive evaluation method,and quadratic assignment procedure analysis method to examine the characteristics and influencing factors of the urban networks of research and development(R&D),production,and sales formed as a result of the overseas investments of listed manufacturing companies in western *** showed that the three types of investment networks involved multiple industry types and multiple central cities with differentiated diversity and *** R&D urban network’s leading sub-industries were the mechanical equipment and instruments,medicine and biological products,and metal and nonmetal *** destination cities were mostly those home to educational and scientific research *** production urban network’s leading sub-industries were the mechanical equipment,instrument,and food and beverage *** destination cities were mostly regional central cities in developing *** sales urban network’s leading sub-industries were the mechanical equipment and instrument,metal and nonmetal,and petrochemical and plastics *** destination cities were numerous and *** addition,the R&D urban network easily formed specialized clusters,core nodes easily controlled the production urban network,and individual nodes did not easily control the sales urban *** and economic system advantages greatly impacted the three network *** the different influencing factors,this study suggests optimizing the institutional investment environment to narrow the institutional gap,adjusting and optimizing the investment layout to expand overseas markets,and increasing R&D funds to stimulate technological progress

关键词： manufacturing industry Global value chain(GVC) overseas investment cross-border networks western China

Assessment of Human Impacts on Vegetation in Built-up Areas in China Based on AVHRR,MODIS and DMSP_OLS Nighttime Light Data,1992–2010

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Chinese Geographical Science 2014年第2期24卷 231-244页

作者： LIU Qinping yang yongchun TIAN Hongzhen ZHANG Bo GU Lei College of Earth and Environmental Sciences Lanzhou University School of Management Tianjin Polytechnic University Key Laboratory of Western China's Environment Systems of the Ministry of Education Lanzhou University Department of Cultural Geography Faculty of Spatial ScienceUniversity of Groningen

Since the reform and opening-up program started in 1978,the level of urbanization has increased rapidly in *** urban expansion and restructuring have had significant impacts on the ecological environment especially within built-up *** this study,ArcGIS 10,ENVI 4.5,and Visual FoxPro 6.0 were used to analyze the human impacts on vegetation in the built-up areas of 656Chinese cities from 1992 to ***,an existing algorithm was refined to extract the boundaries of the built-up areas based on the Defense Meteorological Satellite Program Operational Linescan System(DMSP_OLS)nighttime light *** improved algorithm has the advantages of high accuracy and ***,a mathematical model(Human impacts(HI))was constructed to measure the impacts of human factors on vegetation during rapid urbanization based on Advanced Very High Resolution Radiometer(AVHRR)Normalized Difference Vegetation Index(NDVI)and Moderate Resolution Imaging Spectroradiometer(MODIS)*** values greater than zero indicate relatively beneficial effects while values less than zero indicate proportionally adverse *** results were analyzed from four aspects:the size of cities(metropolises,large cities,medium-sized cities,and small cities),large regions(the eastern,central,western,and northeastern China),administrative divisions of China(provinces,autonomous regions,and municipalities)and vegetation zones(humid and semi-humid forest zone,semi-arid steppe zone,and arid desert zone).Finally,we discussed how human factors impacted on vegetation changes in the built-up *** found that urban planning policies and developmental stages impacted on vegetation changes in the built-up *** negative human impacts followed an inverted′U′shape,first rising and then falling with increase of urban ***′s national policies,social and economic development affected vegetation changes in the built-up *** findings can provide a scientific basis for municipal planning de

关键词： vegetation change human impact urbanization built-up areas nighttime light data Normalized Difference Vegetation Index(NDVI)

‘Partly'globalized networks and driving mechanism in resource-based state-owned enterprises:A case study of J Group

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Geography and Sustainability 2024年第1期5卷 77-88页

作者： Jing Xu yongchun yang Yongjiao Zhang Shan Man College of Earth and Environmental Sciences Lanzhou UniversityLanzhou 730000China Key Laboratory of Western China's Environmental Systems Ministry of Education of the People's Republic of ChinaLanzhou UniversityLanzhou 730000China School of Economics Lanzhou UniversityLanzhou 730000China

In the context of economic globalization,while multinational enterprises from developed countries occupy a high-end position in the global value chain,enterprises from developing countries are often marginalized in the world *** China,resource-based state-owned enterprises(SOEs)are tasked with the mission of safeguarding resource security,and their internationalization development ideas and strategic deployment are significantly and fundamentally different from those of other non-state-owned enterprises and large multinational *** study provides ideas for the globalization policies of enterprises in developing *** consider J Group in western China as a case and discuss its productive investment and global production network development from 2010 to *** found that J Group was‘Partly'globalized,and there are multiple core nodes with the characteristics of centralized and decentralized coexistence in the production network;in addition,the overall layout centre shifted to Southeast Asia and China;however,its global production was restricted by the enterprise's investment security considerations,support and restrictions of the home country,political security risk of the host country,and sanctions from the *** findings provide insights for future research:under the wave of anti-globalization and'internal circulation as the main body',resource SOEs should consider the potential risk of investment,especially keeping the middle and downstream industrial chain in China as much as possible.

关键词： Global production networks Global value chain Productive investment Resource SOEs J Group ‘Partly'globalized

Sulfur-enriched alkaloids from the root of Isatis indigotica

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Acta Pharmaceutica Sinica B 2018年第6期8卷 933-943页

作者： Qinglan Guo Chengbo Xu Minghua Chen Sheng Lin Yuhuan Li Chenggen Zhu JiANDong Jiang yongchun yang Jiangong Shi State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences & Peking Union Medical College

Five new sulfur-enriched alkaloids isatithioetherins A–E(1–5), and two pairs of scalemic enantiomers(t)-and( à)-isatithiopyrin B(6 a and 6 b) and isoepigoitrin and isogoitrin(7 a and 7 b), along with the known scalemic enantiomers epigoitrin and goitrin(8 a and 8 b), were isolated and characterized from an aqueous extract of the Isatis indigotica roots. Their structures were determined by extensive spectroscopic data analysis, including 2 D NMR and theoretical calculations of electronic circular dichroism(ECD) spectra based on the quantum-mechanical time-dependent density functional theory(TDDFT). Compounds 1–5 represent a novel group of sulfur-enriched alkaloids, biogenetically originating from stereoselective assemblies of epigoitrin-derived units. Isolation and structure characterization of 6 a and 6 b support the postulated biosynthetic pathways for the diastereomers 9 a and 9 b via a rare thio-Diels–Alder reaction. Compounds 2 and 4 showed antiviral activity against the influenza virus A/Hanfang/359/95(H3 N2, IC500.60 and 1.92 μmol/L) and the herpes simplex virus 1(HSV-1, IC503.70 and 2.87 μmol/L), and 2 also inhibited Coxsackie virus B3(IC500.71 μmol/L).& 2018 Chinese Pharmaceutical Association and Institute of Materia Medica, Chinese Academy of Medical Sciences. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license(http://***/licenses/by-nc-nd/4.0/).

关键词： Cruciferae Isatis indigotica Sulfur-containing alkaloids Isatithioetherins A–E Isatithiopyrins A and B Isoepigoitrin Isogoitrin Antiviral activity

An Improved Damage Identification Method Based on Mode Information

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Journal of Ocean University of China 2006年第3期5卷 273-277页

作者： yang Fengyan yang yongchun Engineering College Ocean University of China Qingdao 266071 P. R. China

This paper presents a new algorithm to predict locations and severities of damage in structures by changing modal parameters. An existing algorithm of damage detection is reviewed and the new algorithm is formulated to improve the accuracy of damage locating and severity estimation by eliminating the erratic assumptions and limits in the existing algorithm. The damage prediction accuracy is numerically assessed for each algorithm when applied to a two-dimensional frame structure for which pre-damage and post-damage modal parameters are available for only a few modes of vibration. The analysis results illustrate the improved accuracy of the new algorithm when compared to the existing algorithm.

关键词： structural damage nondestructive detection damage identification modal analysis

Nano Au/TiO_2 hollow microsphere membranes for the improved sensitivity of detecting specific DNA sequences related to transgenes in transgenic plants

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Science China Chemistry 2008年第11期51卷 1066-1073页

作者： ZHANG yongchun, yang Tao, ZHOU Na, ZHANG Wei & JIAO Kui College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, China College of Chemistry and Molecular Engineering Qingdao University of Science and Technology Qingdao China

Gold nanoparticles (nano Au)/titanium dioxide (TiO2) hollow microsphere membranes were prepared on the carbon paste electrode (CPE) for enhancing the sensitivity of DNA hybridization detection. The immobilization of nano Au and TiO2 microsphere was investigated with cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The hybridization events were monitored with EIS us-ing [Fe(CN)6]3-/4- as indicator. The sequence-specific DNA of the 35S promoter from cauliflower mosaic virus (CaMV35S) gene was detected with this DNA electrochemical sensor. The dynamic detection range was from 1.0×10-12 to 1.0×10-8 mol/L DNA and a detection limit of 2.3×10-13 mol/L could be ob-tained. The polymerase chain reaction (PCR) amplification of the terminator of nopaline synthase (NOS) gene from the real sample of a kind of transgenic soybean was also satisfactorily detected.

关键词： Au nanoparticle TiO_2 hollow microsphere DNA electrochemical biosensor CaMV35S gene NOS gene

Empirical Research on the Factors of Chinese City Growth in the Transitional Period

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Asian Agricultural Research 2010年第7期2卷 1-5页

作者： LI Yingjie yang yongchun School of Resource and Environmental Science Lanzhou UniversityLanzhou 73000China Key Laboratory of West Chinas Environmental Science Lanzhou 730000China

Based on the definition of the concept of city growth, the paper mainly discussed the factors which impact the growth of Chinese cities in the transitional period by selecting the proportion of city construction land area to the area of the city X1(%), green coverage ratio of the built up area X2(%), the ratio of personnel involved in the secondary industry X3(%), the GDP per capita X4(×104)and other 43 indicators, by relying on the relevant data from China Urban Statistical Yearbook(2008), applying SPSS statistical software and by applying the Factor Analysis and Regression Analysis. The results show that the factors which affect the city growth have four major groups, namely economic and institutional factors, location factors, environmental factors and social cultural services and functions. Among the factors which affect Chinese city growth, the general budgetary expenditures and the general budgetary revenues of local public finance are the most important factors. The general budgetary expenditures of local finance, the general budgetary revenues, the lands of urban construction and other 12 factors obtained by gradually excluding method can be used to present the coefficient of city growth.

关键词： Transitional period City growth Chinese cities Factors China

Interplays of liver fibrosis-associated microRNAs:Molecular mechanisms and implications in diagnosis and therapy

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Genes & Diseases 2023年第4期10卷 1457-1469页

作者： Hong Li Tingli Liu yongchun yang William C.Cho Robin J.Flynn Majid Fasihi Harandi Houhui Song Xuenong Luo Yadong Zheng State Key Laboratory of Veterinary Etiological Biology Key Laboratory of Veterinary Parasitology of Gansu ProvinceLanzhou Veterinary Research InstituteChinese Academy of Agricultural SciencesLanzhouGansu 730046China Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province Zhejiang Provincial Engineering Laboratory for Animal Health Inspection&Internet TechnologyZhejiang International Science and Technology Cooperation Base for Veterinary Medicine and Health ManagementChina-Australia Joint Laboratory for Animal Health Big Data AnalyticsCollege of Animal Science and Technology&College of Veterinary Medicine of Zhejiang A&F UniversityHangzhouZhejiang 311300China Department of Clinical Oncology Queen Elizabeth HospitalHong Kong SAR 999077China Department of Infection Biology Institute of Infection and Global HealthUniversity of LiverpoolLiverpool L35RFUK Graduate Studies Office Department of ResearchInnovation and Graduate StudiesWaterford Institute of TechnologyX91 K0EKIreland Research Center for Hydatid Disease in Iran Kerman University of Medical SciencesKerman ***Iran

microRNAs(miRNAs)are a class of non-coding functional small RNA composed of 21e23 nucleotides,having multiple associations with liver ***-associated miRNAs are roughly classified into pro-fibrosis or anti-fibrosis *** former is capable of activating hepatic stellate cells(HSCs)by modulating pro-fibrotic signaling pathways,mainly including TGF-b/SMAD,WNT/b-catenin,and Hedgehog;the latter is responsible for maintenance of the quiescent phenotype of normal HSCs,phenotypic reversion of activated HSCs(aHSCs),inhibition of HSCs proliferation and suppression of the extracellular matrix-associated gene ***,several miRNAs are involved in regulation of liver fibrosis via alternative mechanisms,such as interacting between hepatocytes and other liver cells via exosomes and increasing autophagy of ***,understanding the role of these miRNAs may provide new avenues for the development of novel interventions against hepatic fibrosis.

关键词： Diagnosis Hepatic stellate cell Liver fibrosis miRNA Therapy