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Comparative Analysis of the Evolution of Community Space in Chengdu-Chongqing Region: A Case Study of Main Urban Areas in Chengdu and Chongqing
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作者 GAO Wei XIAO Yue +12 位作者 HE Yi GUO Zhenni LENG Qinyi LIU Hong KANG Yichen WANG Zhiye ZHU Zeliang WANG Jiamin ZHOU Xu CHAO Yi DONG Hailong MAO Xiao WANG Chensu 《Journal of Landscape Research》 2017年第5期22-26,共5页
Due to the integrated development between Chengdu and Chongqing,there are a large number of residents flowing into the two cities from their surrounding areas,so community renewal is imminent.Because of the similarity... Due to the integrated development between Chengdu and Chongqing,there are a large number of residents flowing into the two cities from their surrounding areas,so community renewal is imminent.Because of the similarity in the historical and cultural background of the two places,a comparative analysis of the evolution of community space in Chengdu-Chongqing Region enables Chengdu and Chongqing learn from each other and speed up the pace of renewal.This paper analyzed the evolution of community space in main urban areas of Chengdu and Chongqing.Specifically,the evolution of community space in Chengdu and Chongqing went through three stages.The starting time of community renewal in the two places was very close,but the duration of each stage varied.The second stage of Chengdu continued for a longer time,so its renovation and renewal of the community space was more detailed and thorough,and the emphasis and extension direction of the evolution of the community space were different.The evolution of community space in both Chengdu and Chongqing went through"mechanical renewal of demolition and construction—small-scale gradual renewal",but the path of renewal and development of the community space in Chengdu was faster.This paper,from the perspective of the evolution of community space,put forward the framework and content of community renewal in Chengdu and Chongqing based on community development and elaborated the community research content based on community development. 展开更多
关键词 chengdu-chongqing region Community space Integrated development Comparative analysis
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Analysis of the Higher Education Research in the Chengdu-Chongqing Region:A Comparative Perspective Based on Three Major Economic Circles in China
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作者 Dai Rui Luo Hong Xie Xiaoli 《Contemporary Social Sciences》 2023年第1期102-115,共14页
Drawing on literature regarding higher education research retrieved from the CNKI database from 1997 to 2021,this paper used CiteSpace to analyze the current status of higher education research in the Chengdu-Chongqin... Drawing on literature regarding higher education research retrieved from the CNKI database from 1997 to 2021,this paper used CiteSpace to analyze the current status of higher education research in the Chengdu-Chongqing economic circle.By comparing it with that in the Beijing-Tianjin-Hebei region,the Guangdong-Hong Kong-Macao Greater Bay Area,and the Yangtze River Delta,this paper concluded that the level of higher education research within a region is in line with the level of the region’s economic and social development.As higher education research in the Chengdu-Chongqing economic circle draws more and more attention,its research areas and topics are becoming increasingly diversified.However,by comparison,the research in this region features a late start and lower participation of researchers and research institutions,resulting in insufficient research in both quantity and quality.Therefore,it is essential to encourage more experts and scholars to participate in higher education research in the Chengdu-Chongqing economic circle.Efforts should also be made to strengthen academic exchanges and cooperation between scholars in Chengdu and Chongqing and establish a long-term cooperation mechanism for higher education research between the two cities.Improved higher education research will definitely facilitate the construction of first-class universities,thus providing human capital and intellectual support for the construction of the Chengdu-Chongqing economic circle. 展开更多
关键词 higher education research chengdu-chongqing economic circle Beijing-Tianjin-Hebei region Guangdong-Hong Kong-Macao Greater Bay Area Yangtze River Delta
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Research on Sports Public Service Supply in the Chengdu-Chongqing Twin-City Economic Circle under the Background of Regional Economic Development
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作者 Yiming Yang Yun Liu Yu Huang 《Proceedings of Business and Economic Studies》 2024年第2期106-113,共8页
Using literature,questionnaires,interviews,and mathematical statistics to investigate the current situation of sports public services in the Chengdu-Chongqing Twin-city Economic Circle.The results show that there are ... Using literature,questionnaires,interviews,and mathematical statistics to investigate the current situation of sports public services in the Chengdu-Chongqing Twin-city Economic Circle.The results show that there are some problems in Chengdu-Chongqing sports public services,such as big difference in the development level of supply between urban and rural areas,low supply level,low efficiency,supply mechanism defect,lack of social sports instructors,an outstanding contradiction between the quality of sports public service and residents’demand.To address the problems,government departments should accelerate the transformation of government functions,improve the relevant regulations and systems,increase the investment in sports public services,improve the quality of supply,cultivate the backbone team,integrate resources,and combine the national characteristics with regional characteristics,take into account the personalized needs of the residents,combine the sports public services with intelligence,and build the service system of“Internet+Fitness.” 展开更多
关键词 regional economy chengdu-chongqing Twin-city Economic Circle Sports demand Sports public service Current supply situation
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Comprehensive evaluation and spatial-temporal evolution characteristics of urban resilience in Chengdu-Chongqing Economic Circle
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作者 Xin Li Shuyi Zhang +1 位作者 Rongxi Ren Yafei Wang 《Chinese Journal of Population,Resources and Environment》 2024年第1期58-67,共10页
To clarify the connotations and extensions of urban resilience,this study focuses on the Chengdu-Chongqing Economic Circle with 16 cities as research subjects.A comprehensive evaluation index system was constructed to... To clarify the connotations and extensions of urban resilience,this study focuses on the Chengdu-Chongqing Economic Circle with 16 cities as research subjects.A comprehensive evaluation index system was constructed to measure the resilience of each city from 2003 to 2020.The spatial-temporal evolution characteristics were analyzed using Kernel density estimation,standard deviation ellipse,and spatial Markov chain analysis,and the spatial Tobit model was introduced to discover the influencing factors.The results indicate the following:①Urban resilience in the Chengdu-Chongqing Economic Circle displays an upward trend,with the center of gravity moving to the southwest,and the polarization phenomenon intensifying.②The urban resilience level in a region has certain spatial and geographical dependence,while the probability of urban resilience transfer differs in adjacent cities with different resilience levels.③Urban centrality,economic scale,openness level,and financial development promote urban resilience,whereas government scale significantly inhibits it.Finally,this paper proposes countermeasures and suggestions to improve the urban resilience of the Chengdu-Chongqing Economic Circle. 展开更多
关键词 chengdu-chongqing Economic Circle Urban resilience Spatial-temporal evolution Driving factor
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The Impact of Digital Finance on High-Quality Development of the Chengdu-Chongqing Economic Circle
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作者 Wei Liangyi Bai Xiaobo Li Qin 《Contemporary Social Sciences》 2024年第2期1-15,共15页
This paper developed a comprehensive evaluation system that was able to quantify the levels of high-quality development across the cities within the Chengdu-Chongqing economic circle,and investigate the impact that di... This paper developed a comprehensive evaluation system that was able to quantify the levels of high-quality development across the cities within the Chengdu-Chongqing economic circle,and investigate the impact that digital finance had on the cities’high-quality development and the underlying mechanisms through which it achieved this.This comprehensive evaluation system was constructed using statistical data from these cities for the period 2014 to 2020 while also taking China’s high-quality development philosophy into account.The key findings revealed that:(a)Digital finance was able to significantly promote high-quality development in the Chengdu-Chongqing economic circle;(b)Digital finance had a significant positive effect in promoting innovative,coordinated,green,open,and shared development;(c)Digital finance was able to stimulate the high-quality development in the Chengdu-Chongqing economic circle by boosting entrepreneurial dynamism;(d)Digital finance had a significant impact on the high-quality development of the axis areas,while its impact was less discernible in non-axis areas.The insights from this research offer a deeper understanding of the factors that drive high-quality development,the role digital finance plays,and the mechanisms through which digital finance is able to propel high-quality development at the city cluster scale. 展开更多
关键词 digital finance chengdu-chongqing economic circle high-quality development
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Thermospheric neutral wind studies over the equatorial region:A review
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作者 Siti Syazwani Nasuha Idahwati Sarudin +1 位作者 Nurul Shazana Abdul Hamid Ahmad Fairuz Omar 《Earth and Planetary Physics》 EI CAS 2025年第1期81-100,共20页
Thermospheric neutral winds(TNWs)refer to the neutral gases in the thermosphere circulating as tides,which play a crucial role in the dynamics of the thermosphere-ionosphere system(TIS).Global geospace neutral winds,p... Thermospheric neutral winds(TNWs)refer to the neutral gases in the thermosphere circulating as tides,which play a crucial role in the dynamics of the thermosphere-ionosphere system(TIS).Global geospace neutral winds,particularly over the magnetic equator,have been a subject of study for several decades.However,despite the known importance of neutral winds,a comprehensive understanding and characterization of the winds is still lacking.Various ground-based and satellite missions have provided valuable information on the contribution of neutral winds to the global atmospheric dynamics.However,efforts in the global monitoring of neutral winds are still lacking,and the drivers behind the behavior of TNWs as well as their influence on the TIS remain incomplete.To address these knowledge gaps in the global circulation of TNWs,it is crucial to develop a deep understanding of the neutral wind characteristics over different regions.The low-latitude equatorial region in particular has been observed to exert complex influences on TNWs because of the unique effects of the Earth’s magnetic field at the dip equator.Studying neutral winds over this region will provide valuable insights into the unique dynamics and processes that occur in this region,thereby enhancing our understanding of their role in the overall dynamics of the TIS.Additionally,through empirical observations,an improved ability to accurately model and predict the behavior of this region can be achieved.This review article addresses challenges in understanding equatorial winds by reviewing historical measurements,current missions,and the interactions of ionospheric and thermospheric phenomena,emphasizing the need for comprehensive measurements to improve global atmospheric dynamics and weather forecasting. 展开更多
关键词 thermospheric neutral wind thermosphere-ionosphere system dip equator equatorial region
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Frontier as Peril and Promise:The Paradox of Xiao Gang's Western Regions
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作者 William A.Julian 《中国比较文学》 北大核心 2025年第1期56-78,44,共24页
This article attempts to unravel a paradox in the frontier poetry of Xiao Gang.Through a close reading of his two homonymous“Ballad of Joining the Military”poems,I highlight two radically divergent ways in which the... This article attempts to unravel a paradox in the frontier poetry of Xiao Gang.Through a close reading of his two homonymous“Ballad of Joining the Military”poems,I highlight two radically divergent ways in which the Southern Liang Prince portrayed Emperor Wu of Han’s conquest of the Western Regions.I argue that these paradoxical significations of empire can be understood through the patterns found within the historiography of the Han period;his lived experience of the Southern Liang’s frontier;and his Buddhist views on the impermanence and essential unreality of worldly manifestations. 展开更多
关键词 frontier poetry Western regions EMPIRE Xiao Gang
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Burden of mental disorders and risk factors in the Western Pacific region from 1990 to 2021
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作者 Ya-Xin Xu Xiao-Xuan Niu +8 位作者 Wen-Chang Jia Jing Wen Xue-Lin Cheng Yan Han Ming-Hui Peng Jing Zhou Yao Liu Sun-Fang Jiang Xiao-Pan Li 《World Journal of Psychiatry》 SCIE 2025年第1期93-105,共13页
BACKGROUND The burden of mental disorders(MD)in the Western Pacific Region(WPR)re-mains a critical public health concern,with substantial variations across demogra-phics and countries.AIM To analyze the burden of MD i... BACKGROUND The burden of mental disorders(MD)in the Western Pacific Region(WPR)re-mains a critical public health concern,with substantial variations across demogra-phics and countries.AIM To analyze the burden of MD in the WPR from 1990 to 2021,along with associated risk factors,to reveal changing trends and emerging challenges.METHODS We used data from the Global Burden of Disease 2021,analyzing prevalence,incidence,and disability-adjusted life years(DALYs)of MD from 1990 to 2021.Statistical methods included age-standardisation and uncertainty analysis to address variations in population structure and data completeness.RESULTS Between 1990 and 2021,the prevalence of MD rose from 174.40 million cases[95%uncertainty interval(UI):160.17-189.84]to 234.90 million cases(95%UI:219.04-252.50),with corresponding DALYs increasing from 22.8 million(95%UI:17.22-28.79)to 32.07 million(95%UI:24.50-40.68).During this period,the burden of MD shifted towards older age groups.Depressive and anxiety disorders were predominant,with females showing higher DALYs for depressive and anxiety disorders,and males more affected by conduct disorders,attention-deficit hyperactivity disorder,and autism spectrum disorders.Australia,New Zealand,and Malaysia reported the highest burdens,whereas Vietnam,China,and Brunei Darussalam reported the lowest.Additionally,childhood sexual abuse and bullying,and intimate partner violence emerged as significant risk factors.CONCLUSION This study highlights the significant burden of MD in the WPR,with variations by age,gender,and nation.The coronavirus disease 2019 pandemic has exacerbated the situation,emphasizing the need for a coordinated response. 展开更多
关键词 Mental disorders Western pacific region Global Burden of Disease Risk factors Disability-adjusted life years
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An Overview of Coordinated Regional Development in China Utilizing CiteSpace Software
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作者 MEI Zhao 《Journal of Landscape Research》 2025年第1期54-58,共5页
The coordinated regional development strategy,recognized as one of China’s seven development strategies,plays a crucial role in reducing regional development disparities,optimizing resource allocation,and facilitatin... The coordinated regional development strategy,recognized as one of China’s seven development strategies,plays a crucial role in reducing regional development disparities,optimizing resource allocation,and facilitating high-quality development.This study analyzes a total of 418 relevant publications from China spanning the years 1998 to 2022.Utilizing CiteSpace software,a visualization analysis of keyword cooccurrence,mutation,and other bibliometric characteristics was conducted.The findings indicate that the number of publications during the specified period exhibited a fluctuating upward trend,with a notable increase observed after 2018.Furthermore,the research demonstrated a weak interdisciplinary crossover and a low intensity of collaboration among authors.The primary thematic areas of focus were identified as follows:connotation,mechanisms,countermeasure and suggestion,and evaluation. 展开更多
关键词 Coordinated regional development CITESPACE VISUALIZATION Graphical analysis
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Cryopreservation of bovine sperm causes single‑strand DNA breaks that are localized in the toroidal regions of chromatin
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作者 Jordi Ribas‑Maynou Rodrigo Muiño +1 位作者 Carolina Tamargo Marc Yeste 《Journal of Animal Science and Biotechnology》 2025年第1期92-106,共15页
Background Sperm cryopreservation is widely used in the cattle industry,as it allows for disassociating the localiza-tion of sires and the collection of semen from the timing of artificial insemination.While freeze-th... Background Sperm cryopreservation is widely used in the cattle industry,as it allows for disassociating the localiza-tion of sires and the collection of semen from the timing of artificial insemination.While freeze-thawing is known to impair sperm DNA integrity,whether the damage induced consists of single-(SSB)or double-strand breaks(DSB)has not been determined.In addition,no previous study has addressed if DNA breaks preferentially reside in specific genome regions such as those forming the toroid linker regions,or are rather spread throughout the regions linked to protamines.The main aim of the present work,therefore,was to elucidate the type and localization of the DNA damage generated by cryopreservation and to evaluate its impact on artificial insemination outcomes in cattle.Results The incidence of SSB and DSB was evaluated in 12 ejaculates before and after cryopreservation with the Comet assay,and the localization of the DNA breaks was assessed using pulsed-field gel electrophoresis(PFGE).Before cryopreservation,the incidence of SSB was 10.99%±4.62%and involved 20.56%±3.04%of sperm cells,whereas these figures significantly(P<0.0001)increased up to 34.11%±3.48%and 53.36%±11.00%in frozen-thawed sperm.In contrast,no significant differences in the incidence of DSB were observed(P>0.990)before and after cryopreservation(before:incidence of 13.91%±1.75%of sperm DNA affecting 56.04%±12.49%of sperm cells;after:incidence of 13.55%±1.55%of sperm DNA involving 53.36%±11.00%of sperm cells).Moreover,PFGE revealed that the percentage of sperm DNA fragments whose length was shorter than a toroid(<31.5 kb)was greater(P<0.0001)after(27.00%±4.26%)than before freeze-thawing(15.57%±4.53%).These differences indicated that the DNA breaks induced by cryopreservation affect the regions condensed in protamines,which are structured in toroids.On the other hand,in vivo fertility rates were associated to the incidence of SSB and DSB in frozen-thawed sperm(P=0.032 and P=0.005),but not with the size of the DNA fragments resulting from these breaks(P>0.05).Conclusion Cryopreservation of bovine sperm generates single-strand DNA breaks,which are mainly located in protamine-condensed toroidal regions.The incidence of DNA breaks in cryopreserved sperm has an impact on cat-tle fertility,regardless of the size of generated fragments. 展开更多
关键词 Cattle DNA damage Fertility Sperm Toroid linker regions
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Advances in regional-scale crop growth and associated process modeling
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作者 Wenfeng LIU Yawei BAI +5 位作者 Taisheng DU Mengxue LI Hong YANG Shichao CHEN Chuanbin LIANG Shaozhong KANG 《Science China Earth Sciences》 2025年第3期653-668,共16页
In the context of global change,ensuring national food security and achieving sustainable development of agricultural production systems have become major challenges worldwide.To address these issues,regional-scale cr... In the context of global change,ensuring national food security and achieving sustainable development of agricultural production systems have become major challenges worldwide.To address these issues,regional-scale crop growth and associated process(CROP-AP)models,with their robust simulation and predictive capabilities,have emerged as important tools for studying a wide range of issues relating to agricultural production at river basin,national,and even global scales.Here,we provide a systematic review of the advances of regional-scale CROP-AP models.First,regional-scale CROP-AP models are categorized based on model characteristics:statistical models,crop growth models,hydrology-crop coupling models,and ecosystem models.The origin,development,principle,structure,and application of each model type are introduced.Then,the main functions of regional-scale CROP-AP models are critically reviewed from five aspects:crop yield prediction,crop water consumption,agricultural non-point source pollution,greenhouse gas emissions,and climate change impact and responses.Finally,the future development trends and research priorities of regional-scale CROP-AP models are explored from six key perspectives:model validation and calibration,the ability to simulate the coupling of crop physiology and human activities,enhancing model scalability,multi-model ensembles,data and code sharing,and the integration of artificial intelligence.This review aims to provide comprehensive references and insights for the further development and application of large-scale,high-precision CROP-AP models. 展开更多
关键词 regional scale Crop model Biophysical processes Model functions Global change
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Effects of clay content distribution on soil hydrothermal responses in the Lake Chad region:Numerical investigation
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作者 Ni An Teodolina Lopez +3 位作者 Raphael Antoine Yujun Cui Weikang Song Haijun Hu 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第3期1786-1800,共15页
Understanding water dynamics under the effect of climatic conditions is important to improve water sustainability over the medium-and long-term.Clay content can affect soil hydrothermal properties,and hence modify wat... Understanding water dynamics under the effect of climatic conditions is important to improve water sustainability over the medium-and long-term.Clay content can affect soil hydrothermal properties,and hence modify water and heat exchange between soil and atmosphere,e.g.evapotranspiration and infiltration.This work aims to develop a numerical approach to explore the influence of clay content on soil hydrothermal response to the timely climatic conditions in the Lake Chad region,Sahel Region of west-central Africa.The meteorological information at the studied points,i.e.points A and B with a clay content of 8.3%and 25%,during the year 2008 is collected from ERA5-Land hourly data.The numerical results allow for understanding the effect of clay content on the hydrothermal response of the surface soil layer.Specifically,the soil surface temperature under point A is lower than that under point B during the dry season due to the dominant effect of heat conduction.However,the converse tendency is observed during the wet season because of the combined effect of heat conduction and latent heat.The variations of soil volumetric water content are closely related to the timely interaction between the soil and atmosphere,in addition to the hydrothermal properties of soil.Moreover,the outcomes of this work improve the understanding of the heat and water dynamics under the effect of climatic conditions and clay content,and provide further insights into the potential water protection in arid and semi-arid regions in the future. 展开更多
关键词 Clay content Soil hydrothermal response Lake Chad region Numerical investigation Soil surface temperature
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Research and Practice on the Specialty Construction of Acupuncture and Massage to Serve the Regional Economic and Social Development
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作者 Mingjun LIU Xiaochao GANG +2 位作者 Changchun MA Chongwen ZHONG Jianzhong CUI 《Asian Agricultural Research》 2025年第3期40-42,共3页
In order to effectively implement China s national strategy of developing the country through science and education and strengthening the country through talents,it is essential to continue to strengthen the system of... In order to effectively implement China s national strategy of developing the country through science and education and strengthening the country through talents,it is essential to continue to strengthen the system of cultivating talents in Chinese medicine.This will enable the country to more effectively serve the development needs of the regional economy and society.It is of particular importance to further develop Chinese medicine-related specialties in this process,such as acupuncture and massage.By conducting meticulous research and practical investigation into the specialty construction of acupuncture and massage,we are able to significantly enhance the quality of training for those pursuing a career in Chinese medicine.This,in turn,strengthens the overall capacity of the field to contribute to the economic and social development of the region.This is not only crucial for the advancement of TCM education,but also offers a valuable point of reference for further research and practice in the domain of medical education. 展开更多
关键词 regional economic and social development Acupuncture and massage Specialty construction of TCM Medical education
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Styles and Characteristics of Thematic Art Creation in Hong Kong,Macao,and Taiwan Regions
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作者 Yanqing Liu 《Journal of Contemporary Educational Research》 2025年第1期255-261,共7页
This article explores the styles and characteristics of thematic art creation in Hong Kong,Macao,and Taiwan regions,analyzing the uniqueness of these regions’artistic backgrounds,artistic languages,theme selections,a... This article explores the styles and characteristics of thematic art creation in Hong Kong,Macao,and Taiwan regions,analyzing the uniqueness of these regions’artistic backgrounds,artistic languages,theme selections,and expressive techniques.The art creation in Hong Kong,Macao,and Taiwan regions is deeply influenced by traditional Chinese culture while incorporating Western artistic elements,exhibiting a diversified artistic style.Thematic art creation in these three regions has its own distinct features,including a deep exploration of local culture and a sensitive capture of the spirit of the times,which together constitute a rich and colorful artistic landscape in Hong Kong,Macao,and Taiwan regions. 展开更多
关键词 Hong Kong Macao and Taiwan regions Thematic art creation Artistic style
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Geographical Indications and Regional Public Brands of the Whole Rice Industry Chain in the Yangtze River Economic Belt
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作者 Min ZHANG Li GAO +2 位作者 Dongjing LI Juncheng ZHU Bin HU 《Asian Agricultural Research》 2025年第1期1-13,共13页
The Yangtze River Economic Belt is the main rice producing area in China.The rice industry chain is the agricultural pillar industry chain of this economic belt and it is the key to ensuring national food security and... The Yangtze River Economic Belt is the main rice producing area in China.The rice industry chain is the agricultural pillar industry chain of this economic belt and it is the key to ensuring national food security and promoting comprehensive rural revitalization.This study discusses the entire rice industry chain in the Yangtze River Economic Belt from the national rice production functional zones,agricultural product quality and safety,national famous and excellent new agricultural products,national specialty agricultural products,"China's good grain and oil"products,and national advantageous characteristic industrial clusters.Then,it discusses the geographical indications of rice and its products in this economic belt from geographical indication products,geographical indication trademarks,agricultural geographical indications,geographical indication standards,geographical indication special indications,national geographical indication product protection demonstration zones,and Chinese geographical indication products protected by the European Union.In addition,it analyzes the five main problems between geographical indications and public brands,such as the limited use of geographical indication specific signs and the imperfect intellectual property protection system for geographical indications.Finally,it proposes eight strategies,including promoting the high-quality development of the entire rice industry chain,creating a geographical indication regional public brand for rice and its products,and implementing geographical indication protection projects. 展开更多
关键词 Yangtze River Economic Belt Rice and its products Entire industry chain Geographical indication regional public brand
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Spatial Patterns and Controlling Factors of Soil Organic Carbon and Total Nitrogen in the Three River Headwaters Region,China
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作者 CUI Qiao LI Zongxing +2 位作者 FENG Qi ZHANG Baijuan ZHAO Yue 《Chinese Geographical Science》 2025年第1期131-148,共18页
The alpine ecosystem has great potential for carbon sequestration.Soil organic carbon(SOC)and total nitrogen(TN)are highly sensitive to climate change,and their dynamics are crucial to revealing the effect of climate ... The alpine ecosystem has great potential for carbon sequestration.Soil organic carbon(SOC)and total nitrogen(TN)are highly sensitive to climate change,and their dynamics are crucial to revealing the effect of climate change on the structure,function,and services of the ecosystem.However,the spatial distribution and controlling factors of SOC and TN across various soil layers and vegetation types within this unique ecosystem remain inadequately understood.In this study,256 soil samples in 89 sites were collected from the Three River Headwaters Region(TRHR)in China to investigate SOC and TN and to explore the primary factors affecting their distribution,including soil,vegetation,climate,and geography factors.The results show that SOC and TN contents in 0-20,20-40,40-60,and 60-80 cm soil layers are 24.40,18.03,14.04,12.40 g/kg and 2.46,1.90,1.51,1.17 g/kg,respectively;with higher concentrations observed in the southeastern region compared to the northwest of the TRHR.One-way analysis of variance reveals that SOC and TN levels are elevated in the alpine meadow and the alpine shrub relative to the alpine steppe in the 0-60 cm soil layers.The structural equation model explores that soil water content is the main controlling factor affecting the variation of SOC and TN.Moreover,the geography,climate,and vegetation factors notably indirectly affect SOC and TN through soil factors.Therefore,it can effectively improve soil water and nutrient conditions through vegetation restoration,soil improvement,and grazing management,and the change of SOC and TN can be fully understood by establishing monitoring networks to better protect soil carbon and nitrogen. 展开更多
关键词 controlling factors different soil layers soil organic carbon(SOC) soil total nitrogen(TN) alpine ecosystem the Three River Headwaters region(TRHR) China
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What are the underlying causes and dynamics of land use conflicts in metropolitan junction areas?A case study of the central Chengdu–Chongqing region in China
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作者 TIAN Junfeng WANG Binyan +1 位作者 QIU Cheng WANG Shijun 《Regional Sustainability》 2024年第3期81-98,共18页
Land use conflicts(LUCs),as a spatial manifestation of the conflicts in the human-land relationships,have a profound impact on regional sustainable development.For China’s metropolitan junction areas(MJAs),the existe... Land use conflicts(LUCs),as a spatial manifestation of the conflicts in the human-land relationships,have a profound impact on regional sustainable development.For China’s metropolitan junction areas(MJAs),the existence of“administrative district economies”has made the issue of LUCs more prominent.Based on a case study of the central Chengdu–Chongqing region,we conducted an exploratory spatial data analysis of the evolutionary process of regional LUCs.Furthermore,structural equation modeling was utilized to analyze the dynamic mechanism of LUCs in MJAs,with a particular emphasis on exploring the influences of administrative boundary.The results showed that from 2010 to 2020,LUCs in the central Chengdu–Chongqing region continued to worsen,and the spatial process conflict and spatial structure conflict indices increased by more than 30.0%.The intensification of LUCs in the central Chengdu–Chongqing region from 2010 to 2020 was mainly the result of the deterioration of conflicts in evaluation units with low conflict levels.LUCs in China’s metropolitan areas generally presented a circular gradient distribution,weakening from the core to the periphery,but there were some strong isolated conflict zones in the outer regions.LUCs in China’s MJAs were the result of interactions among multiple factors,e.g.,natural environment,socio-economic development,policy and institutional processes,and administrative boundary effects.Administrative boundary affected the flow of socio-economic elements,changing the supply-and-demand competition of stakeholders for land resources,consequently exerting an indirect influence on LUCs.This study advances the theory of the dynamic mechanism of LUCs,and provides theoretical support for the governance of these conflicts in transboundary areas. 展开更多
关键词 Land use conflicts Urban agglomerations Administrative boundary Land resources Structural equation modeling(SEM) Central chengdu-chongqing region
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Does digitalization mitigate regional inequalities?Evidence from China 被引量:1
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作者 Haimeng Liu Xinyang Wang +1 位作者 Zheye Wang Yu Cheng 《Geography and Sustainability》 CSCD 2024年第1期52-63,共12页
Regional inequality significantly influences sustainable development and human well-being.In China,there exists pronounced regional disparities in economic and digital advancements;however,scant research delves into t... Regional inequality significantly influences sustainable development and human well-being.In China,there exists pronounced regional disparities in economic and digital advancements;however,scant research delves into the interplay between them.By analyzing the economic development and digitalization gaps at regional and city levels in China,extending the original Cobb-Douglas production function,this study aims to evaluate the impact of digitalization on China's regional inequality using seemingly unrelated regression.The results indicate a greater emphasis on digital inequality compared to economic disparity,with variable coefficients of 0.59 for GDP per capita and 0.92 for the digitalization index over the past four years.However,GDP per capita demonstrates higher spatial concentration than digitalization.Notably,both disparities have shown a gradual reduction in recent years.The southeastern region of the Hu Huanyong Line exhibits superior levels and rates of economic and digital advancement in contrast to the northwestern region.While digitalization propels economic growth,it yields a nuanced impact on achieving balanced regional development,encompassing both positive and negative facets.Our study highlights that the marginal utility of advancing digitalization is more pronounced in less developed regions,but only if the government invests in the digital infrastructure and education in these areas.This study's methodology can be utilized for subsequent research,and our findings hold the potential to the government's regional investment and policy-making. 展开更多
关键词 regional inequality regional disparities Digital divide DIGITALIZATION Sustainable development Economic growth Seemingly unrelated regression
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Organic Matter Accumulation in the Upper Permian Dalong Formation from the Lower Yangtze Region,South China 被引量:3
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作者 FANG Chaogang ZHANG Chengcheng +5 位作者 MENG Guixi XU Jinlong XU Naicen LI Hualing LIU Mu LIU Bo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期150-167,共18页
The Late Permian was marked by a series of important geological events and widespread organic-rich black shale depositions,acting as important unconventional hydrocarbon source rocks.However,the mechanism of organic m... The Late Permian was marked by a series of important geological events and widespread organic-rich black shale depositions,acting as important unconventional hydrocarbon source rocks.However,the mechanism of organic matter(OM)enrichment throughout this period is still controversial.Based on geochemical data,the marine redox conditions,paleogeographic and hydrographic environment,primary productivity,volcanism,and terrigenous input during the Late Permian in the Lower Yangtze region have been studied from the Putaoling section,Chaohu,to provide new insights into OM accumulation.Five Phases are distinguished based on the TOC and environmental variations.In Phase I,anoxic conditions driven by water restriction enhanced OM preservation.In Phase II,euxinic and cycling hydrological environments were the two most substantial controlling factors for the massive OM deposition.During Phase III,intensified terrestrial input potentially diluted the OM in sediment and the presence of oxygen in bottom water weakened the preservation condition.Phase IV was characterized by a relatively higher abundance of mercury(Hg)and TOC(peak at 16.98 wt%),indicating that enhanced volcanism potentially stimulated higher productivity and a euxinic environment.In Phase V,extremely lean OM was preserved as a result of terrestrial dilutions and decreasing primary productivity.Phases I,II and IV are characterized as the most prominent OM-rich zones due to the effective interactions of the controlling factors,namely paleogeographic,hydrographic environment,volcanism,and redox conditions. 展开更多
关键词 GEOCHEMISTRY redox condition primary productivity OM accumulation Lopingian/Changhsingian Lower Yangtze region
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