Influence of Transportation Accessibility on Urban-rural Income Disparity and Its Spatial Heterogeneity

Transportation accessibility has been treated as an important means of reducing the urban-rural income disparity.However,only a few studies have examined the effects of different types of transportation accessibility on urban-rural income disparity and their spatial heterogeneity.Based on data from 285 prefecture-level(and above)Chinese cities in 2000,2005,2010,2015,and 2020,this study uses spatial econometric models to examine how highway accessibility and railway accessibility influence the urban-rural income disparity and to identify their spatial heterogeneity.The result reveals that highway accessibility and railway accessibility have‘coreperiphery’ring-like circle structures.The urban-rural income disparity exhibits strong spatial clustering effects.Both highway accessibility and railway accessibility are negatively associated with urban-rural income disparity,and the former having a greater effect size.Moreover,there is a substitution effect between highway accessibility and railway accessibility in the whole sample.Furthermore,these associations differ in geographic regions.In the central region,highway accessibility is more important in reducing the urban-rural income disparity,but its effect is weakened with the increase of railway accessibility.In the western region,railway accessibility has a larger effect on narrowing the urban-rural income disparity,and this effect is strengthened by the increase of highway accessibility.We conclude that improving transportation accessibility is conducive to reducing the urban-rural income disparity but its effect is spatial heterogenetic.Highways and railways should be developed in a coordinated manner to promote an integrated transport network system.

Study on the Influence of Lanzhou-Urumqi High-Speed Railway on Regional Accessibility and Economic Development

The Lanzhou-Urumqi high-speed railway is an important part of the railway network connecting Gansu,Qinghai,and Xinjiang,and it is of far-reaching significance in facilitating China’s western development.An accessibility model and a double difference model were built to analyze the impact of the Lanzhou-Urumqi high-speed railway on regional accessibility and economic development of the areas along the line before(2012-2014)and after(2017-2019)its opening.The results show that the regional accessibility remains unchanged before and after the operation of this railway line.However,there is a spatial difference in improvement,that of central cities being better.The opening of the high-speed railway is conducive to driving the overall economic development of the region and promoting the comprehensive and coordinated development of regional economies.

Accessibility and utilization of healthcare services among diabetic patients:Is diabetes a poor man’s ailment?

Diabetes is a non-communicable ailment that has adverse effects on the individual’s overall well-being and productivity in society.The main objective of this study was to examine the empirical literature concerning the association between diabetes and poverty and the accessibility and utilization of medical care services among diabetic patients.The diabetes literature was explored using a literature review approach.This review revealed that diabetes is an ailment that affects all individuals irrespective of socioeconomic status;however,its prevalence is high in low-income countries.Hence,despite the higher prevalence of diabetes in developing countries compared with developed countries,diabetes is not a poor man’s ailment because it affects individuals of all incomes.While the number of diabetic patients that access and utilize diabetes medical care services has increased over the years,some personal and institutional factors still limit patients’access to the use of diabetes care.Also,there is a lacuna in the diabetes literature concerning the extent of utilization of available healthcare services by diabetic patients.

Dek219 encodes the DICER-LIKE1 protein that affects chromatin accessibility and kernel development in maize

Chromatin accessibility plays a vital role in gene transcriptional regulation.However,the regulatory mechanism of chromatin accessibility,as well as its role in regulating crucial gene expression and kernel development in maize(Zea mays)are poorly understood.In this study,we isolated a maize kernel mutant designated as defective kernel219(dek219),which displays opaque endosperm and embryo abortion.Dek219 encodes the DICER-LIKE1(DCL1)protein,an essential enzyme in mi RNA biogenesis.Loss of function of Dek219 results in significant reductions in the expression levels of most mi RNAs and histone genes.Further research showed that the Heat shock transcription factor17(Hsf17)-Zm00001d016571 module may be one of the factors affecting the expression of histone genes.Assay results for transposase-accessible chromatin sequencing(ATAC-seq)indicated that the chromatin accessibility of dek219 is altered compared with that of wild type(WT),which may regulate the expression of crucial genes in kernel development.By analyzing differentially expressed genes(DEGs)and differentially accessible chromatin regions(ACRs)between WT and dek219,we identified 119 candidate genes that are regulated by chromatin accessibility,including some reported to be crucial genes for kernel development.Taken together,these results suggest that Dek219 affects chromatin accessibility and the expression of crucial genes that are required for maize kernel development.

Chicken chromatin accessibility atlas accelerates epigenetic annotation of birds and gene fine-mapping associated with growth traits

The development of epigenetic maps, such as the ENCODE project in humans, provides resources for gene regulation studies and a reference for research of disease-related regulatory elements. However,epigenetic information, such as a bird-specific chromatin accessibility atlas, is currently lacking for the thousands of bird species currently described.The major genomic difference between birds and mammals is their shorter introns and intergenic distances, which seriously hinders the use of humans and mice as a reference for studying the function of important regulatory regions in birds. In this study, using chicken as a model bird species, we systematically compiled a chicken chromatin accessibility atlas using 53 Assay of Transposase Accessible Chromatin sequencing(ATAC-seq)samples across 11 tissues. An average of 50 ?796open chromatin regions were identified per sample,cumulatively accounting for 20.36% of the chicken genome. Tissue specificity was largely reflected by differences in intergenic and intronic peaks, with specific functional regulation achieved by two mechanisms: recruitment of several sequence-specific transcription factors and direct regulation of adjacent functional genes. By integrating data from genome-wide association studies, our results suggest that chicken body weight is driven by different regulatory variants active in growth-relevant tissues. We propose CAB39L(active in the duodenum), RCBTB1(muscle and liver), and novel long non-coding RNA ENSGALG00000053256(bone) as candidate genes regulating chicken body weight. Overall, this study demonstrates the value of epigenetic data in fine-mapping functional variants and provides a compendium of resources for further research on the epigenetics and evolution of birds and mammals.

Using ArcGIS to Study Transportation Accessibility of Cultural Tourism Resources with Wan'an County in Jiangxi Province as an Example

This paper reviews cultural tourist attractions and transportation conditions of Wan'an County in Jiangxi Province,and calculates the accessibility and kernel density of transportation network by using ArcGIS.Through the analysis,it obtains the spatial relationship between the accessibility of Wan an County and the spatial structural characteristics of"one center,two clusters,two verticals and one horizontal"presented by the cultural tourism resources.Based on this,the paper puts forward the transportation development suggestions for the development of cultural tourism for Wan'an County.

Geostatistical Analysis of Accessibility to Secondary Schools in Parts of Benue State

This research studied accessibility to secondary schools in some parts of Benue State. The objective of the study was to determine the level of accessibility to secondary school. The study adopted survey, field observation and measurement to obtain the needed data. The study adopted gravity model as the related theoretical framework. GIS and descriptive statistical techniques were employed to map, visualize and analyze the data. The result shows that accessibility to secondary school in the three Local Government Areas is generally low, though it varies between schools, within and between Local Government Areas. This depicts a very stressful schooling condition for the majority of students, and has far-reaching implications in terms of lack of skilled manpower, inadequate facilities and consequently low standards in the educational system. To ensure effective and valid decision-making, and maintain high standards in the system, it was recommended that equitable and systematic distribution of school facilities should be embraced. Furthermore, more schools should be established in the areas which currently have low accessibility to bridge the accessibility gap and encourage active participation and consistent attendance at schools among the students.

Spatial Accessibility of Emergency Facilities to Road Accident Victims in Federal Capital City

This paper studied the spatial accessibility of emergency facilities to road accident victims in Federal Capital City to determine the sufficiency of existing emergency health care facilities and rescue facilities in servicing accident victims. This is useful for developing means of saving the lives of accident victims in the Federal Fapital City (FCC). The data used comprised of Nigerian Sat II 2013 multispectral imagery (5 m multispectral and 2.5 m Panchromatic) of FCC obtained from the National Space Research and Development Agency (NARSDA), coordinates of seventy (70) accident black spots, five (5) zebra points and sixteen (16) emergency health care facilities obtained from Federal Road Safety Commission (FRSC). ArcGIS 10.0 software was used to display, visualize, identify and extract features from the imagery, and create maps from different layers of the spatial data, choose colors and symbols, create buffer zones, analyze spatial relationships, and design map layouts. Purposeful sampling method was adopted to administer 99 questionnaires to accident victims in the hospitals within the FCC. The spatial data were used to determine the time of rescue, type of rescue and coverage time of rescue operation. The statistical data were used to assess the spatio-temporal distribution of accidents and determine the level of response by the rescue teams. The results show that accident victims have adequate access to health facilities but inadequate access to zebra points, and passers-by have more effective accident response than the government action agencies. Specific points for the creation of additional zebra points were identified through buffering, and the creation of sustainable Good Samaritan programs and training for community persons in first aid were suggested. Meanwhile, further research to determine the impact of time of rescue, type of rescue and category of hospital on the accident victims was suggested.

Accessibility Measures in Modal Choice Models: A Proof of Concept Applied to Freight Transport

Modal choice models applied to interregional or international freight transportation network models are often based on rather coarse origin-destination matrices, containing annual transported tonnages between (sub)regions, for instance. Generally, only basic (sometimes constructed) independent variables (transportation costs or transit times) are used because other variables such as shipment sizes, service frequencies, etc. are not available. Using origin-destination matrices and an assignment model, it is also possible to compute spatial accessibility measures that can further be used as additional explanatory variables. Indeed, several published studies have identified network accessibility as an important element in the mode-choice decision. This paper also shows that the inclusion of an accessibility measure in the utility functions of a logit model substantially improves the performance of a transportation network model, both in the modal choice and the assignment levels of the classical four-step model. Consequently, the assignment of the estimated modal demands results in more accurate estimated traffic on the networks. The model presented in this paper is to be considered as a proof of concept because its workflow should further be streamlined to make it easily useable by modelers.

GIS-Based Analysis to Identify the Distribution and Accessibility of Urban Green Space in Dhaka Metropolitan City, Bangladesh

Urban Green Space (UGS) plays an important role in minimizing the negative effects of urbanization on city dwellers, which is predominantly factored into the accessibility to UGS. This study elucidated the distribution and accessibility of UGS in Dhaka, Bangladesh considering the paucity of such important scientific studies in the given area. The methodological structure of this study employed a multispectral Landsat satellite image from 2020 for identifying the logically defined UGSs, as well as a minimum proxy distance being the parameter to estimate accessibility to the UGS through a primary survey scheme and literature review. Considering UGS as a public area, we adopted a hybrid (combination of supervised and unsupervised classification) method followed by post-classification for UGS distribution assessment. The unsupervised classification identified the overall distribution of green spaces, whereas the anomalies of generated classes were rectified during the post-classification. Following the study findings, UGS in Dhaka metropolitan city accounts for only 602 ha or 1.9% of the total geographical space, with Ramna thana ranked as the highest contributor of 111 ha. However, in terms of accessibility to the UGS by city residents, 19.9% of the buildings in Dhaka metropolitan city were computed to be within the determined proxy distance of 500 m around the UGS. Also, parallel to UGS distribution, green space in Ramna thana (111 ha) exhibited the highest accessibility rate (64%) to the UGS compared with other thanas in Dhaka metropolitan city. The baseline findings will contribute to the long-term sustainable urban planning and development of more accessible green spaces in the study area.

Urban Accessibility in Motorcycle Dependent Cities - Case Study in Ho Chi Minh City, Vietnam

Motorcycle dependent cities have specific characteristics in terms of urban accessibility.A rapid increase in the number of motorcycles and other private motorized modes make transport problems more serious and cause severe capacity problems for the infrastructure systems in these cities.Therefore,it is necessary to optimize the development of different modes to meet travel demand and to ensure accessibility in all urban areas.This paper aims to explore accessibility conditions in Ho Chi Minh City,a typical motorcycle dependent city in Vietnam.Understanding of accessibility could be the key element for urban planning in Ho Chi Minh City in particular and motorcycle dependent cities in general.Then,management measures for motorcycles and competitive modes will be proposed to improve the accessibility conditions and thus support sustainable urban transport development for motorcycle dependent cities.

基于Accessibility Service的Android外挂插件实现原理及防御措施

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。

Accessibility Comparison and Spatial Differentiation of Xi’an Scenic Spots with Different Modes Based on Baidu Real-time Travel

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.

Transport Accessibility and Spatial Connections of Cities in the Guangdong-Hong Kong-Macao Greater Bay Area

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.

Spatial variation of the relationship between transport accessibility and the level of economic development in Qinghai-Tibet Plateau, China

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.

Spatiotemporal evolution of land transportation networks and accessibility in inland mountainous areas 1917-2017:A case study of Southwest China

Located in the western hinterland,Southwest China is a typical mountainous area covered by plateaus,mountains and hills.Its ruggedness hinders regional internal and external connections,and its poor transportation infrastructure has long constrained the socioeconomic development of Southwest China.Based on the GIS transportation database,this paper explored the spatiotemporal evolution and characteristics of the land transportation networks and the accessibility of Southwest China from 1917 to 2017.Regional accessibility in Southwest China has significantly improved,and transportation infrastructure has gradually integrated the transportation circles of the52 central cities.The transportation network has followed an evolutionary process from a"hub-spoke pattern"to a"network pattern",while the construction of a high-speed railway(HSR)has brought about significant spatial polarization.We argue that innovation in transportation technology is one of the most effective factors for promoting a significant change in regional accessibility.In addition,the spatial distribution and evolution of accessibility in Southwest China presents a verticalcharacteristic that distinguishes it from the plains,as the spillover effects of new transportation infrastructure on accessibility improvement are partly offset by the mountainous terrain.Additionally,in Southwest China,there is significant"path dependence"in the evolution of the transportation network,since a large portion of the population is concentrated along transportation corridors in mountainous areas.

The landscape of chromatin accessibility in skeletal muscle during embryonic development in pigs

Background:The development of skeletal muscle in pigs during the embryonic stage is precisely regulated by transcriptional mechanisms,which depend on chromatin accessibility.However,how chromatin accessibility plays a regulatory role during embryonic skeletal muscle development in pigs has not been reported.To gain insight into the landscape of chromatin accessibility and the associated genome-wide transcriptome during embryonic muscle development,we performed ATAC-seq and RNA-seq analyses of skeletal muscle from pig embryos at 45,70 and 100 days post coitus(dpc).Results:In total,21,638,35,447 and 60,181 unique regions(or peaks)were found across the embryos at 45 dpc(LW45),70 dpc(LW70)and 100 dpc(LW100),respectively.More than 91%of the peaks were annotated within−1 kb to 100 bp of transcription start sites(TSSs).First,widespread increases in specific accessible chromatin regions(ACRs)from embryos at 45 to 100 dpc suggested that the regulatory mechanisms became increasingly complicated during embryonic development.Second,the findings from integrated ATAC-seq and RNA-seq analyses showed that not only the numbers but also the intensities of ACRs could control the expression of associated genes.Moreover,the motif screening of stage-specific ACRs revealed some transcription factors that regulate muscle developmentrelated genes,such as MyoG,Mef2c,and Mef2d.Several potential transcriptional repressors,including E2F6,OTX2 and CTCF,were identified among the genes that exhibited different regulation trends between the ATAC-seq and RNA-seq data.Conclusions:This work indicates that chromatin accessibility plays an important regulatory role in the embryonic muscle development of pigs and regulates the temporal and spatial expression patterns of key genes in muscle development by influencing the binding of transcription factors.Our results contribute to a better understanding of the regulatory dynamics of genes involved in pig embryonic skeletal muscle development.

Spatial Accessibility of Road Network in Wuhan Metropolitan Area Based on Spatial Syntax

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.

Equity of Accessibility to Health Care Services and Identification of Underserved Areas

Characterizing the availability of opportunities to residents has been a long-term aim in health care geographic investigation.It is important to measure the degree of inequity in health care accessibility and to identify underserved areas, due to the uneven distribution of health care services. In this study, JavaScript was used to calculate travel time based on Amap, as this can provide a more reliable data support to measure the health care accessibility in Xi’an communities, China. Based on the overall equity, herein, an attempt was made to quantify the equity of health care accessibility, and to identify health care underserved areas inside the different communities. Results show that the accessibility to low-level health care services is high in the northern areas and low in the southern areas, while the accessibility to high-level and comprehensive health care services shows a clear core-periphery spatial structure. Moreover, the overall equity of the health care accessibility is relatively low, and the inequity of high-level health care accessibility is further aggravated.Furthermore, the quantified equity of accessibility to high-level and comprehensive health care services in the central urban areas is better;however low-level health care services are relatively inadequate. There are significant differences among health care underserved areas, in particular, for the worst equity and the lowest accessibility areas(A1) and the worse equity and the lowest accessibility areas(B1) in high-level underserved areas. Notably, the sharing of health care services and the reasonable flow of health technical personnel among different levels of health institutions can make the high-level health care services in the central urban areas have a greater trickle effect on the surrounding areas.

U.S. national parks accessibility and visitation

Accessibility is a factor affecting national park visitation.However,the effect of accessibility on national park visitation is not fully understood.This paper examines the relationship between U.S.national park visitation and accessibility.First,the global and local accessibility indexes of each park unit are computed based on an accessibility model that takes into account the surrounding population and its proximity to the park unit.Integrated in the model is a distance decay coefficient that is derived from U.S.national park visitor surveys and therefore pertinent to the case of study.Then correlation analysis is performed between park visitation and accessibility based on park types,regions,and visitation types.Results show that total visitation is positively related to accessibility in National Memorials,Military Parks and Battlefield Parks/Sites but negatively related to accessibility in national parks and national monuments.However,recreational overnight stay visits are commonly negatively correlated to accessibility for almost all park types.Moreover,local accessibility index displays enhanced correlation coefficients with improved significance levels in many categories of analysis.Results suggest that historical/cultural national parks which often show positive correlations tend to attract more local visitors,but nature-based parks which mainly show negative correlations tend to attract more distant visitors.