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Chromatin accessibility regulates axon regeneration
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作者 Isa Samad Brett J.Hilton 《Neural Regeneration Research》 2026年第4期1548-1549,共2页
Central nervous system(CNS) axons fail to regenerate following brain or spinal cord injury(SCI),which typically leads to permanent neurological deficits.Peripheral nervous system axons,howeve r,can regenerate followin... Central nervous system(CNS) axons fail to regenerate following brain or spinal cord injury(SCI),which typically leads to permanent neurological deficits.Peripheral nervous system axons,howeve r,can regenerate following injury.Understanding the mechanisms that underlie this difference is key to developing treatments for CNS neurological diseases and injuries characterized by axonal damage.To initiate repair after peripheral nerve injury,dorsal root ganglion(DRG) neurons mobilize a pro-regenerative gene expression program,which facilitates axon outgrowth. 展开更多
关键词 peripheral nerve injurydorsal root ganglion drg central nervous system nervous system developing treatments spinal cord injury chromatin accessibility central nervous system cns spinal cord
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Improving service accessibility and equity for sustainable development goals without newly facilities by rural settlement reconstruction
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作者 Caihui Cui Zhigang Han +3 位作者 Feng Liu Jingru Ma Haiying Wang Xiang Chen 《Geography and Sustainability》 2025年第1期105-117,共13页
Ensuring the provision of accessible,affordable,and high-quality public services to all individuals aligns with one of the paramount aims of the United Nations’Sustainable Development Goals(SDGs).In the face of esca ... Ensuring the provision of accessible,affordable,and high-quality public services to all individuals aligns with one of the paramount aims of the United Nations’Sustainable Development Goals(SDGs).In the face of esca lating urbanization and a dwindling rural populace in China,reconstructing rural settlements to enhance public service accessibility has become a fundamental strategy for achieving the SDGs in rural areas.However,few stud ies have examined the optimal methods for rural settlement reconstruction that ensure accessible and equitable public services while considering multiple existing facilities and service provisions.This paper focuses on rural settlement reconstruction in the context of the SDGs,employing an inverted MCLP-CC(maximal coverage loca tion problem for complementary coverage)model to identify optimal rural settlements and a rank-based method for their relocation.Conducted in Changyuan,a county-level city in Henan Province,China,this study observed significant enhancements in both accessibility and equity following rural settlement reconstruction by utilizing the MH3SFCA(modified Huff 3-step floating catchment area)and the spatial Lorenz curve method.Remarkably,these improvements were achieved without the addition of new facilities,with the accessibility increasing by 44.21%,4.97%,and 3.11%;Gini coefficients decreasing by 19.53%,1.64%,and 3.18%;Ricci-Schutz coef-ficients decreasing by 21.09%,2.09%,and 4.33%for educational,medical,and cultural and sports facilities,respectively.It indicated that rural settlement reconstruction can bolster the accessibility and equity of public ser-vices by leveraging existing facilities.This paper provides a new framework for stakeholders to better reconstruct rural settlements and promote sustainable development in rural areas in China. 展开更多
关键词 SDGs EQUITY accessibility Rural settlement reconstruction Spatial optimization
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International Overview of Accessibility Icons and Labels: Between Social Uses and Regulations
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作者 Frédéric Reichhart Aggée Célestin Lomo Myazhiom 《Sociology Study》 2025年第5期205-229,共25页
Since the 1970s,a series of international and national sources have supported the principle of accessibility,which slowly has become a statuary norm and a legislative obligation.Each country has implemented accessibil... Since the 1970s,a series of international and national sources have supported the principle of accessibility,which slowly has become a statuary norm and a legislative obligation.Each country has implemented accessibility through a singular policy.But in addition to the accessibility of a place or an activity,to inform about what is accessible is very important as well,and has not really taken off.Indeed,for disabled people,the difficulty lies not only with access to places and the use of resources,but also with the visibility of these resources.This means that information concerning accessibility has to be disclosed and provided effectively to disabled people,those involved with them and the relevant institutions.In different countries all over the world,many labels and pictograms have been created for this purpose and give information relating to accessibility.Using a socio-historical approach,we will present and analyze the different types of icons,symbols,pictograms and labels that have been put in place around the world and in France:what are they used for and for whom are they made?We will show that they are pointers which firstly reflect the diversity and range within the target group concerned by accessibility,and secondly the evolution of accessibility as a dynamic and ecological principle. 展开更多
关键词 LABEL pictogram accessibility people with a disability
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Chromatin accessibility module identified by single-cell sequencing underlies the diagnosis and prognosis of hepatocellular carcinoma
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作者 Xiao-Li Xi Yi-Dong Yang +2 位作者 Hui-Ling Liu Jie Jiang Bin Wu 《World Journal of Hepatology》 2025年第6期211-231,共21页
BACKGROUND Hepatocellular carcinoma(HCC)is notorious for its aggressive progression and dismal prognosis,with chromatin accessibility dynamics emerging as pivotal yet poorly understood drivers.AIM To dissect how multi... BACKGROUND Hepatocellular carcinoma(HCC)is notorious for its aggressive progression and dismal prognosis,with chromatin accessibility dynamics emerging as pivotal yet poorly understood drivers.AIM To dissect how multilayered chromatin regulation sustains oncogenic transcription and tumor-stroma crosstalk in HCC,we combined multiomics single cell analysis.METHODS We integrated single-cell RNA sequencing and paired single-cell assay for transposase-accessible chromatin with sequencing data of HCC samples,complemented by bulk RNA sequencing validation across The Cancer Genome Atlas,Liver Cancer Institute,and GSE25907 cohorts.Cell type-specific chromatin architectures were resolved via ArchR,with regulatory hubs identified through peak-to-gene linkages and coaccessibility networks.Functional validation employed A485-mediated histone 3 lysine 27 acetylation suppression and small interfering RNA targeting DGAT1.RESULTS Malignant hepatocytes exhibited expanded chromatin accessibility profiles,characterized by increased numbers of accessible peaks and larger physical regions despite reduced peak intensity.Enhancer-like peaks enriched in malignant regulation,forming long-range hubs.Eighteen enhancer-like peak-related genes showed tumor-specific overexpression and diagnostic accuracy,correlating with poor prognosis.Intercellular coaccessibility analysis revealed tumor-stroma symbiosis via shared chromatin states.Pharmacological histone 3 lysine 27 acetylation inhibition paradoxically downregulated DGAT1,the hub gene most strongly regulated by chromatin accessibility.DGAT1 knockdown suppressed cell proliferation.CONCLUSION Multilayered chromatin reprogramming sustains HCC progression through tumor-stroma crosstalk and DGAT1-related oncogenic transcription,defining targetable epigenetic vulnerabilities. 展开更多
关键词 Hepatocellular carcinoma Single-cell multiomics Chromatin accessibility Enhancer-like peak Chromatin coaccessibility
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Telemedicine in Action:Improving Perceived Healthcare Accessibility in Rural China
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作者 Zhongmou Huang Xizi Wan +1 位作者 Shaojie Zhou Miao Yu 《Health Care Science》 2025年第3期215-224,共10页
Objective:The scarcity of healthcare resources and inadequate access to medical services in rural and remote areas are pervasive challenges many countries face,particularly in the developing world.Telemedicine,with it... Objective:The scarcity of healthcare resources and inadequate access to medical services in rural and remote areas are pervasive challenges many countries face,particularly in the developing world.Telemedicine,with its capacity to overcome geographical barriers and provide patients with real‐time medical services,has shown considerable potential in addressing these issues,attracting wide-spread attention.Compact medical communities and family doctor systems play important roles in improving healthcare accessibility.However,despite the critical nature of patients'perceptions of healthcare accessibility,research in this domain is sparse.This study aimed to explore the impact of telemedicine on rural residents'perceived healthcare accessibility in China,analyze the mechanisms underpinning this relationship,and elucidate the roles of compact medical communities and the family doctor system.Methods:Survey data from 3311 rural residents were analyzed using a probit model,instrumental variables,and subgroup regression analyses to ascertain causal effects,perform heterogeneity analysis,examine mechanisms,and ascertain the robustness of the findings.Results:Telemedicine significantly enhanced rural residents'perceived healthcare accessibility,with particularly notable benefits for those in sparsely populated areas,regions with high‐speed internet access,within the purview of compact healthcare consortiums,and those with access to family doctor services.Furthermore,telemedicine improved rural residents'perceived healthcare accessibility by encouraging the use of primary care services.Conclusion:Telemedicine in China has played a significant role in improving the perceived healthcare accessibility among rural residents and aiding in the reduction of disparities in accessibility across different demographic groups.This is consistent with the broader objective of achieving universal health coverage.However,the efficacy of telemedicine in enhancing healthcare accessibility is contingent upon certain preconditions.Policymakers must confront local infrastructure challenges,particularly regarding internet connectivity,when expanding telemedicine services to ensure their effective operation.The synergistic interaction observed between telemedicine,the family doctor system,and compact medical communities highlights the importance of integrating telemedicine into existing healthcare systems.Such integration could enhance collaboration with current healthcare frameworks,ensuring the provision of safe,accessible,and affordable healthcare services,and promoting the health and well‐being of local populations. 展开更多
关键词 compact medical community developing countries family doctor system health equity healthcare accessibility primary care rural health TELEMEDICINE
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基于Accessibility Service的Android外挂插件实现原理及防御措施 被引量:2
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作者 陈冬 王太成 《软件导刊》 2019年第11期140-143,共4页
为解决传统反外挂技术难以有效防御基于Accessibility Service的Android应用程序外挂问题,通过反编译已知的基于Accessibility Service的移动外挂插件,从AccessibilityService源码剖析入手,分析其实现原理和外挂模式,从而有针对性地提... 为解决传统反外挂技术难以有效防御基于Accessibility Service的Android应用程序外挂问题,通过反编译已知的基于Accessibility Service的移动外挂插件,从AccessibilityService源码剖析入手,分析其实现原理和外挂模式,从而有针对性地提出通过AccessibilityManager有效检测外挂插件,实现Android应用程序有意识屏蔽关键UI节点的获取和点击事件这两种有效防御措施。实验结果表明,综合采用这两种防御措施,对已知外挂插件及通过签名变种的外挂插件识别准确率分别达到100%和92%。综合应用AccessibilityManager检测外挂插件及屏蔽关键UI节点和点击事件这两种防御措施能有效防御基于Accessibility Service的Android应用程序外挂。 展开更多
关键词 accessibility SERVICE Android外挂 外挂分析 外挂防御 反外挂
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China's regional transport dominance: Density, proximity, and accessibility 被引量:63
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作者 JIN Fengjun WANG Chengjin LI Xiuwei WANG Jiao'e 《Journal of Geographical Sciences》 SCIE CSCD 2010年第2期295-309,共15页
Transport infrastructure plays an important role in shaping the configuration of spatial socio-economic structures and influences regional accessibility. This paper defines transport dominance from three aspects: qua... Transport infrastructure plays an important role in shaping the configuration of spatial socio-economic structures and influences regional accessibility. This paper defines transport dominance from three aspects: quafity, quantity, and advantage, measured by density, proximity, and accessibility indices. County is the basic unit for analysis. The results reveal: (1) Transport dominance statistically follows a partial normal distribution. A very few counties, 1.4% of the total, have extremely high transport dominance which strongly supports the socio-economic development in these areas. In contrast, one eighth of all counties have poor transport dominance which impedes local socio-economic development to some extent. The remaining areas, about 70% of the counties, have median transport dominance. (2) Transport dominance is spatially unevenly distributed, with values decreasing gradually from the coastal area to the inland area. Areas in the first-highest level of transport dominance are mainly concentrated in the Yangtze River Delta, the Greater Beijing area, and the Pearl River Delta. Areas in the second-highest level are focused in Chengdu, Chongqing, and Wuhan metropolitan areas. Provincial capitals and a few other counties belong to the third-highest level. 展开更多
关键词 transport dominance DENSITY PROXIMITY accessibility China
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Accessibility Comparison and Spatial Differentiation of Xi’an Scenic Spots with Different Modes Based on Baidu Real-time Travel 被引量:6
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作者 WANG Li CAO Xiaoshu +1 位作者 LI Tao GAO Xingchuan 《Chinese Geographical Science》 SCIE CSCD 2019年第5期848-860,共13页
A study of the accessibility of a city’s scenic spots via different travel modes can contribute to optimization of tourism-related transportation while improving tourists’ travel-related satisfaction levels and adva... A study of the accessibility of a city’s scenic spots via different travel modes can contribute to optimization of tourism-related transportation while improving tourists’ travel-related satisfaction levels and advancing tourism. We systematically analyzed the accessibility of 56 scenic spots in Xi’an City, China, via car and public transport travel modes using the real-time travel function of the Baidu Maps API(Application Programming Interface) along with spatial analysis methods and the modal accessibility gap index of scenic spots. We obtained the following results. First, maximum and minimum travel times using public transport exceeded those using cars. Moreover, the accessibility of scenic spots via cars and public transport presented a circular spatial pattern of increasing travel time from the center to the periphery. Contrasting with travel by public transport, car travel showed a clear time-space compression effect. Second, accessibility of the scenic spots via cars and public transport showed some spatial heterogeneity, with no clear advantages of car accessibility in the central urban area. However, advantages of car accessibility were increasingly evident moving from the center to the periphery. Third, whereas the correlation of the modal accessibility gap index of scenic spots in Xi’an with global space was significantly positive, local spatial interdependence was only evident in some inner city areas and in marginal areas. Moreover, spatial heterogeneity was evident in two regions but was insignificant in other areas, indicating that the spatial interdependence of the modal accessibility gap index in most scenic spots was not apparent in terms of the overall effect of public transport routes, road networks, and the distribution of scenic spots. The improvement of public transport coverage in marginal areas and the optimization of public transport routes in central urban areas are essential tasks for improving travel using public transport in the future. 展开更多
关键词 BAIDU REAL-TIME TRAVEL car accessibility public transport accessibility modal accessibility gap SCENIC spots Xi’an City
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Rural settlement spatial patterns and effects: Road traffic accessibility and geographic factors in Guangdong Province, China 被引量:16
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作者 YANG Ren XU Qian +1 位作者 XU Xuanfang CHEN Yanchun 《Journal of Geographical Sciences》 SCIE CSCD 2019年第2期213-230,共18页
Based on land use classification data of remote sensing images, using kernel density, the minimal cumulative resistance model of road traffic accessibility, and a logistic regression model, the characteristics of the ... Based on land use classification data of remote sensing images, using kernel density, the minimal cumulative resistance model of road traffic accessibility, and a logistic regression model, the characteristics of the spatial pattern and the main factors influencing it were quantitatively examined in Guangdong Province from 1990 to 2013. The framework of the research concerning rural settlement evolution and its effect mechanisms were also discussed and generalized for the future. The results are as follows:(1) The spatial distribution of rural settlements showed spatial directivity of low altitude, low slope, and adjacent to rivers, as well as to villages and towns; thus a special pattern was formed, which was dense on the plains, sparse in mountainous areas, and included two core high density regions of rural settlements in the Chaoshan plain in the east and the Zhanjiang plain tableland region in the west. The spatial distribution of rural settlements was located along the rivers, valleys, and roads with traffic in the mountainous regions surrounding the Pearl River Delta region.(2) In addition to the spatial orientation of the open road, it was important to show that the accessibility of road traffic to the township has had the greatest influence on the spatial distribution of the rural settlements. The connected transport network between towns and villages is significant for rural transformation as a comprehensive increase in township production and service capacity will be the key to optimizing the town-village system in rural areas.(3) Elevation and slope were two basic but influential factors that have affected the distribution, scale, and form of rural settlements. The attributes of the physical geography are the first elements in optimizing village layout and planning spatial reconstruction.(4) In the current Internet and social media era, the reconstruction of market network system orders connects with the global market network system in rural areas. The rural life service circle will be constructed with the township at its core to explore the theory and practice of spatial reconstruction, including its production, life and ecology, and socio-cultural heritage and protection. It will also allow for exploration of the rural settlements' evolution, rural spatial production, rural social networks, group behavior, social autonomy, and social and cultural fields, which will bethe core focus of China's rural spatial reconstruction research against a background of globalization. 展开更多
关键词 RURAL SETTLEMENT spatial feature recognition TRAFFIC accessibility RURAL GEOGRAPHY
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Transport Accessibility and Spatial Connections of Cities in the Guangdong-Hong Kong-Macao Greater Bay Area 被引量:9
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作者 CAO Xiaoshu OUYANG Shishu +3 位作者 YANG Wenyue LUO Yi LI Baochao LIU Dan 《Chinese Geographical Science》 SCIE CSCD 2019年第5期820-833,共14页
Based on geographic information system(GIS) spatial analysis technology, the spatial pattern of raster grid transport accessibility for the Guangdong-Hong Kong-Macao Greater Bay area was studied and the states of spat... Based on geographic information system(GIS) spatial analysis technology, the spatial pattern of raster grid transport accessibility for the Guangdong-Hong Kong-Macao Greater Bay area was studied and the states of spatial connectedness were simulated using highway passenger transport, railway passenger transport, port passenger transport and aviation passenger transport data. The result shows that transport accessibility within the Guangdong-Hong Kong-Macao Greater Bay area costs ‘one hour’ and the spatial distribution of accessibility in the area presents clear ‘core-periphery’ spatial characteristics, with Guangzhou, Foshan, Shenzhen constituting the core. The transport accessibility of Guangdong-Hong Kong-Macao is high. Average accessibility of urban nodes as measured by travel time is 0.99 h, and the areas accessible within 1.42 h occupy 79.14% of the total area. Most of the areas with the lowest accessibility are found in the peripheral area, with the worst accessibility being 4.73 h. Compared with the west-side cities, the economically developed east-side cities of the Guangdong-Hong Kong-Macao Greater Bay area have higher connectivity with roads, railways, ports, and aviation transport. Guangzhou, Foshan, Zhuhai, Shenzhen, Hong Kong and Macao are closely linked. The higher the accessibility, the closer the intercity connectedness. 展开更多
关键词 transport accessibility urban SPATIAL connection Guangdong-Hong Kong-Macao GREATER BAY Area China
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The study on county accessibility in China: Characteristics and effects on population agglomeration 被引量:8
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作者 WANG Zhenbo XU Jiangang +2 位作者 FANG Chuanglin XU Lu QI Yi 《Journal of Geographical Sciences》 SCIE CSCD 2011年第1期18-34,共17页
This paper calculated spatial accessibility of all counties (city,urban district) in China with cost weighted distance method. Region divisions of county accessibility were conducted,and relation of traffic accessib... This paper calculated spatial accessibility of all counties (city,urban district) in China with cost weighted distance method. Region divisions of county accessibility were conducted,and relation of traffic accessibility and population aggregation was discussed in this paper. The results indicated that county accessibility in China had mainly low values and a distribution structure of circle layer and reverse-to-natural gradient. There was an obvious correlation between county accessibility and population density in China. With these analyses,inner mechanisms of population migration in different traffic conditions and region types were revealed,and can provide useful proposals to regional planning,traffic planning and smart distribution of people in China. 展开更多
关键词 COUNTY spatial accessibility population aggregation raster cost weighted China
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Regional accessibility of land traffic network in the Yangtze River Delta 被引量:9
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作者 ZHANG Li LU Yuqi 《Journal of Geographical Sciences》 SCIE CSCD 2007年第3期351-364,共14页
In a given district, the accessibility of any point should be the synthetically evaluation of the internal and external accessibilities. Using MapX component and Delphi, the author presents an information system to ca... In a given district, the accessibility of any point should be the synthetically evaluation of the internal and external accessibilities. Using MapX component and Delphi, the author presents an information system to calculate and analyze regional accessibility according to the shortest travel time, generating thus a mark diffusing figure. Based on land traffic network, this paper assesses the present and the future regional accessibilities of sixteen major cities in the Yangtze River Delta. The result shows that the regional accessibility of the Yangtze River Delta presents a fan with Shanghai as its core. The top two most accessible cities are Shanghai and Jiaxing, and the bottom two ones are Taizhou (Zhejiang province) and Nantong With the construction of Sutong Bridge, Hangzhouwan Bridge and Zhoushan Bridge, the regional internal accessibility of all cities will be improved. Especially for Shaoxing, Ningbo and Taizhou (Jiangsu province), the regional internal accessibility will be decreased by one hour, and other cities will be shortened by about 25 minutes averagely. As the construction of Yangkou Harbor in Nantong, the regional external accessibility of the harbor cities in Jiangsu province will be speeded up by about one hour. 展开更多
关键词 regional accessibility land traffic network Yangtze River Delta GIS
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Spatial variation of the relationship between transport accessibility and the level of economic development in Qinghai-Tibet Plateau, China 被引量:7
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作者 YANG Xue-ting QIU Xiao-ping +2 位作者 FANG Yi-ping XU Yun ZHU Fu-biao 《Journal of Mountain Science》 SCIE CSCD 2019年第8期1883-1900,共18页
As an important component of China’ transportation systems, for a long time, the insufficient performance of transport in QinghaiTibet Plateau(QTP) was a bottleneck restricting the economic growth and social developm... As an important component of China’ transportation systems, for a long time, the insufficient performance of transport in QinghaiTibet Plateau(QTP) was a bottleneck restricting the economic growth and social development in this area. Nevertheless, the implementation of the western development strategy has accelerated the preliminary construction of comprehensive transport network since 2000. Due to the large area and significant geographical heterogeneity, there is a growing need to understand the relationship between transportation and economic development based on the perspective of spatial difference. By using GIS-based raster analysis and Geographically Weighted Regression(GWR) model, we investigated the spatial-temporal distribution of highway, railway and airport accessibility, respectively, and estimated the correlation and heterogeneity between transport accessibility and the level of economic development. Results revealed that:(1) Transport accessibility in the QTP improved by 53.38% in the past 15 years, which is specifically embodied in the improvement of both highway and railway.(2) Accessibility presented prominent differentiation in the space, increasing from west to east and reducing with the rise of elevation, specifically, the best accessibility area of the highway is below 4000 m above sea level, while the area with an altitude of over 4000 m has the lowest aviation time cost.(3) In general, the long weighted average time cost to critical transport facilities posed significantly negative effect on county economic growth in QTP, more positively, the adverse effect gradually weakened over time.(4) Obvious heterogeneity exists at the influence of different transport accessibility factors on the level of economic development, reflecting both in the horizontal space and altitudinal belt. Therefore, region-specific policies should be addressed for the sustainable development of transport facilities as well as economy in the west mountain areas. 展开更多
关键词 accessibility RASTER cost WEIGHTED Geographically WEIGHTED regression Economic effect Spatial variations
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Evolution, accessibility and dynamics of road networks in China from 1600 BC to 1900 AD 被引量:5
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作者 WANG Chengjin DUCRUET Cesar WANG Wei 《Journal of Geographical Sciences》 SCIE CSCD 2015年第4期451-484,共34页
Before the emergence of modern modes of transport, the traditional road infra structure was the major historical means of carrying out nationwide socioeconomic exchange However, the history of transport infrastructure... Before the emergence of modern modes of transport, the traditional road infra structure was the major historical means of carrying out nationwide socioeconomic exchange However, the history of transport infrastructure has received little attention from researchers. Given this background, the work reported here examined the longterm development of transport networks in China. The national road network was selected for study and the 3500 years from 1600 BC to 1900 AD was chosen as the study period. Indicators were designed for the maturity level of road networks and an accessibility model was developed for the paths of the shortest distance. The evolution of the road network in China since the Shang Dynasty (1600 BC) was described and its major features were summarized to reveal longterm regu larities. The maturity level of the road network and its accessibility was assessed and regions with good and poor networks were identified. The relationship between China's natural, social and economic systems and the road network were discussed. Our analysis shows that the road network in China has a number of longterm regularities. The continuously expanding road network follows a path of inland expansion especially towards the border areas. How ever, its coverage and accessibility are characterized by a coreperipheral configuration, which has close relationships with, not only the natural conditions, but also national defense and warfare. The centralization of national power, national land governance, postal transport, the transport of specialized cargos, and international trade are also related to the develop ment of the road network. This research draws attention to the evolving regularities of trans port networks. 展开更多
关键词 China road networks historical evolution accessibility dynamic mechanisms
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Transnational Economic Connection Analysis Based on Railway Class Accessibility Between China and Russia 被引量:3
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作者 CHU Nanchen ZHANG Pingyu LI He 《Chinese Geographical Science》 SCIE CSCD 2019年第5期872-886,共15页
Under the background of ‘the Belt and Road’ initiative, the economic cooperation has great potential between China and Russia. The railway accessibility has an important influence on the economic connections of citi... Under the background of ‘the Belt and Road’ initiative, the economic cooperation has great potential between China and Russia. The railway accessibility has an important influence on the economic connections of cities along the railway line. This paper studied the Sino-Russian transnational economic connection based on the railway class accessibility along Trans-Siberian railway(the transnational China railway branch line). The results are as following. First, the railway accessibility of the Chinese nodes is stronger than that of the Russian nodes, which in general displays a tendency of space attenuation from China to the Sino-Russian border, then to Russia. Spatially, the railway accessibility within the study area shows a ‘High East, Low West’ and ‘High South, Low North’ spatial pattern. The railway accessibility of the nodes, which are located at the beginning and end of the railway line, is weaker than those nodes located in the middle of the line. Second, the railway accessibility and external economic connection intensity summation of the nodes show a positive relationship along the railway line. The economic connection intensity summation of different nodes presents obvious regional differentiation. Finally, as economic connection network has evolved, the small world effect of Sino-Russian railway economic connection network becomes strong. 展开更多
关键词 RAILWAY class accessibility ECONOMIC CONNECTION intensity spatial pattern China Russia
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Oxycarbonylation of methanol over modified CuY: Enhanced activity by improving accessibility of active sites 被引量:3
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作者 Hexin Zhou Shengping Wang +2 位作者 Baowei Wang Xinbin Ma Shouying Huang 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第3期775-778,共4页
CuY zeolite is a promising catalyst in the field of manufacturing dimethyl carbonate(DMC) through oxidative carbonylation of methanol. Cu^+ exchanged with Br?nsted acid sites are supposed to be active for this reactio... CuY zeolite is a promising catalyst in the field of manufacturing dimethyl carbonate(DMC) through oxidative carbonylation of methanol. Cu^+ exchanged with Br?nsted acid sites are supposed to be active for this reaction. However, the location of Cu^+ in small cages can not interact with reactants because of steric hindrance, which lead to a waste of Cu species. In this work, NH_4F solution was used to modify the pore structure of zeolite Y by etching the framework T atoms. Physical and chemical adsorption of probe molecules with different size are used to determine the changes of porosity as well as the accessibility of Cu^+ sites. At an optimized etching time, the small cages were opened with maintained zeolitic framework. As a result, more Cu^+ species located in small cages become accessible to reactants, which contributes to the enhanced activity in this reaction. 展开更多
关键词 CARBONYLATION of METHANOL POST-TREATMENT accessibility ZEOLITE Y NH4F solution ETCHING
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Spatial Accessibility of Road Network in Wuhan Metropolitan Area Based on Spatial Syntax 被引量:6
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作者 Chengliang Liu Ruilin Yu 《Journal of Geographic Information System》 2012年第2期128-135,共8页
Based on space syntax theory, the spatial accessibility of the road network in Wuhan Metropolitan Area has been quantitatively analyzed by building a series of accessibility variables. Topologic connectivity in the ac... Based on space syntax theory, the spatial accessibility of the road network in Wuhan Metropolitan Area has been quantitatively analyzed by building a series of accessibility variables. Topologic connectivity in the accessible rings appears to be broken;traffic axis network is in spatial structure of hub-and-spoke and fishbone-like. Meanwhile, the differences in classified road network have led to inefficiency of its network servo and its ever-worsening capability to respond to traffic jams. Besides, two band-like integrated cores of which one is east to west along the Yangtze River and the other is north to south along Beijing to Guangzhou Railway, have become the first level traffic axis in the whole network, which is responsible for the connectivity of the entire metropolitan area network. This consequently has strengthened the dominant position of Wuhan which is located on the bands’ crossing. In short, the spatial accessibility of that classified space morphology, the urban system, the transport infrastructure as well as the social and economic development of Wuhan Metropolitan Area are highly interrelated to each other, especially to the high level highway network featured by freeways, the development level of which is well in line with that of road network accessibility. 展开更多
关键词 accessibility ROAD Network Space SYNTAX WUHAN METROPOLITAN Area
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Access数据库技术及其运用
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作者 朱秋海 《消费电子》 2025年第6期200-202,共3页
随着科学技术的持续进步,信息技术行业逐渐进步与发展。在数字化背景下,为提升数据存储管理的效率,减少人工失误,Access数据库技术应用的重要性日益凸显,受到社会各界广泛关注,基于此,简单分析Access数据库技术理论基础及其应用方法,并... 随着科学技术的持续进步,信息技术行业逐渐进步与发展。在数字化背景下,为提升数据存储管理的效率,减少人工失误,Access数据库技术应用的重要性日益凸显,受到社会各界广泛关注,基于此,简单分析Access数据库技术理论基础及其应用方法,并深入探究基于Access数据库的实例应用,具体涉及系统结构、员工基本情况表的思考与设计等内容,以供业内人士参考。 展开更多
关键词 access 数据库技术 应用
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Evolution and geographic effects of high-speed rail in East Asia: An accessibility approach 被引量:19
19
作者 金凤君 焦敬娟 +1 位作者 齐元静 杨宇 《Journal of Geographical Sciences》 SCIE CSCD 2017年第5期515-532,共18页
The rapid development of high-speed rail(HSR) is influencing regional development, regional structure, commuting, and regional integration. East Asia is the region with the world's first and largest current operati... The rapid development of high-speed rail(HSR) is influencing regional development, regional structure, commuting, and regional integration. East Asia is the region with the world's first and largest current operating and planned HSR network. In this paper, we examine the evolutionary mechanism and impacts on the transport circle and accessibility of HSR in East Asia. The results indicate that the HSR network first follows a "core-core" model and then forms a corridor in Japan, South Korea, and China Taiwan, but then forms a complete network in China Mainland. The current operating HSR lines are mostly distributed in regions with developed economies and dense populations, and more than half of the population and GDP in China can be served by HSR within 1 hour's travel time. The planned HSR network will expand to the western region of China and Japan and the southern region of South Korea. The development of the current operating and planned HSR network considerably enlarges the transport circle of core cities, especially cities along trunk HSR lines. This 1 h transport circle of core cities has formed continuous regions in the Yangtze River Delta, the Pearl River Delta, Tokyo, Seoul, and along trunk HSR lines. The HSR network will bring about substantial improvement in accessiblity, but also increase the inequality of nodal accessibility in China Mainland. Spatially, the spatial patterns of the weighted shortest travel time of cities in China Mainland, Japan, and South Korea all present the "core-peripheral structure", taking Zhengzhou, Tokyo, and Seoul, respectively, as core cities, and cities located along the trunk HSR lines gain large improvement in accessibility. 展开更多
关键词 high-speed rail East Asia evolutionary mechanism geographic effects accessibility
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Understanding Relationship Between Accessibility and Economic Growth:A Case Study from China(1990–2010) 被引量:11
20
作者 JIAO Jingjuan WANG Jiaoe +1 位作者 JIN Fengjun DU Chao 《Chinese Geographical Science》 SCIE CSCD 2016年第6期803-816,共14页
China′s economy and transport infrastructure have both experienced rapid development since 1978, and especially since 1990. Today, China is the second-largest economic entity in terms of GDP and has the largest high-... China′s economy and transport infrastructure have both experienced rapid development since 1978, and especially since 1990. Today, China is the second-largest economic entity in terms of GDP and has the largest high-speed rail(HSR) network and the second-largest expressway network in the world. This paper explores the relationship between accessibility and economic growth in China from 1990 to 2010. In the study, the basic research units include 333 prefecture-level cities and four municipalities. We explore a bivariate analysis framework of accessibility and economic growth, and their increase rates, to examine this relationship using long-term panel data. The results indicate that, first, accessibility and economic growth show a significant positive relationship using both cross-section and panel data, while the increase rate in accessibility and GDP indicate no significant relationship using cross-section data and a poor significant relationship using panel data. Second, the distributions of local advantage are uneven. Cities with low local advantage with respect to accessibility and GDP are mainly located in China′s eastern coastal region or the provincial capitals, while those with low local advantage in terms of their increase rates are located in the western region. Third, as China′s economic growth and transport networks have evolved, the distribution of local advantage shows little change in terms of accessibility and GDP, but a greater change in terms of their increase rates, which is largely influenced by the distribution of expressway and HSR networks. 展开更多
关键词 accessibility economic growth China GDP transport infrastructure
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