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Mapping and measuring urban-rural inequalities in accessibility to social infrastructures 被引量:1
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作者 Chenmeng Guo Weiqi Zhou +1 位作者 Chuanbao Jing Dawa Zhaxi 《Geography and Sustainability》 CSCD 2024年第1期41-51,共11页
Equal access to social infrastructures is a fundamental prerequisite for sustainable development,but has long been a great challenge worldwide.Previous studies have primarily focused on the accessibility to social inf... Equal access to social infrastructures is a fundamental prerequisite for sustainable development,but has long been a great challenge worldwide.Previous studies have primarily focused on the accessibility to social infras-tructures in urban areas across various scales,with less attention to rural areas,where inequality can be more severe.Particularly,few have investigated the disparities of accessibility to social infrastructures between urban and rural areas.Here,using the Changsha-Zhuzhou-Xiangtan urban agglomeration,China,as an example,we investigated the inequality of accessibility in both urban and rural areas,and further compared the urban-rural difference.Accessibility was measured by travel time of residents to infrastructures.We selected four types of social infrastructures including supermarkets,bus stops,primary schools,and health care,which were funda-mentally important to both urban and rural residents.We found large disparities in accessibility between urban and rural areas,ranging from 20 min to 2 h.Rural residents had to spend one to two more hours to bus stops than urban residents,and 20 min more to the other three types of infrastructures.Furthermore,accessibility to multiple infrastructures showed greater urban-rural differences.Rural residents in more than half of the towns had no access to any infrastructure within 15 min,while more than 60%of the urban residents could access to all infrastructures within 15 min.Our results revealed quantitative accessibility gap between urban and rural areas and underscored the necessity of social infrastructures planning to address such disparities. 展开更多
关键词 accessibility Social infrastructures Urban-rural difference INEQUALITY Regional sustainability
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Which Neighborhoods Have Easier Access to Online Home Delivery Services?A Spatiotemporal Accessibility Analysis in Nanjing,China
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作者 KONG Yu ZHEN Feng +1 位作者 ZHANG Shanqi SHEN Lizhen 《Chinese Geographical Science》 SCIE CSCD 2024年第4期722-738,共17页
The rise in online home delivery services(OHDS)has had a significant impact on how urban services are supplied and used in recent years.Studies on the spatial accessibility of OHDS are emerging,but few is known about ... The rise in online home delivery services(OHDS)has had a significant impact on how urban services are supplied and used in recent years.Studies on the spatial accessibility of OHDS are emerging,but few is known about the temporal dimension of OHDS accessibility as well as the geographic and socioeconomic differences in the spatiotemporal accessibility of OHDS.This study measures the spatiotemporal accessibility of four types of OHDS,namely leisure,fresh and convenient,medical,and catering services.The geographic and socioeconomic disparities in the spatiotemporal accessibility of these four types of OHDS are then identified using spatial statistical methods and the Kruskal-Wallis test(K-W test).The case study in Nanjing,China,suggests that:1)spatiotemporal accessibility better reflects the temporal variation of OHDS accessibility and avoids overestimation of OHDS accessibility when only considering its spatial dimension.2)The spatiotemporal accessibility of OHDS varies geographically and socioeconomically.Neighborhoods located in the main city or neighborhoods with higher housing prices,higher population density,and higher point of interest(POI)mix have better OHDS spatiotemporal accessibility.Our study contributes to the understanding of OHDS accessibility from a spatiotemporal perspective,and the empirical insights can assist policymakers in creating intervention plans that take into account variations in OHDS spatiotemporal accessibility. 展开更多
关键词 online home delivery services(OHDS) spatiotemporal accessibility neighborhoods accessibility differences Nanjing City China
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Al-modified yolk-shell silica particle-supported NiMo catalysts for ultradeep hydrodesulfurization of dibenzothiophene and 4,6-dimethyldibenzothiophene:Efficient accessibility of active sites and suitable acidity
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作者 Ke Yu Wei-Min Kong +3 位作者 Zhen Zhao Ai-Jun Duan Lian Kong Xi-Long Wang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期654-666,共13页
Yolk-shell SiO2 particles(YP)with center-radial meso-channels were fabricated through a simple and effective method.Al-containing YP-supported NiMo catalysts with different Al amounts(NiMo/AYP-x,x=Si/Al molar proporti... Yolk-shell SiO2 particles(YP)with center-radial meso-channels were fabricated through a simple and effective method.Al-containing YP-supported NiMo catalysts with different Al amounts(NiMo/AYP-x,x=Si/Al molar proportion)were prepared and dibenzothiophene(DBT)and 4,6-dimethyl-dibenzothiophene(4,6-DMDBT)were employed as the probes to evaluate the hydrodesulfurization(HDS)catalytic performance.The as-prepared AYP-x carriers and corresponding catalysts were characterized by some advanced characterizations to obtain deeper correlations between physicochemical properties and the HDS performance.The average pore sizes of series AYP-x supports are above 6.0 nm,which favors the mass transfer of organic sulfides.The cavity between the yolk and the shell is beneficial for the enrichment of S-containing compounds and the accessibility between reactants and active metals.Aluminum embedded into the silica framework could facilitate the formation of Lewis(L)and Brønsted(B)acid sites and adjust the metal-support interaction(MSI).Among all the as-synthesized catalysts,NiMo/AYP-20 catalyst shows the highest HDS activities.The improved HDS activity of NiMo/AYP-20 catalyst is attributed to the perfect combination of excellent structural properties of the yolk-shell mesoporous silica,enhanced acidity,moderate MSI,and good accessibility/dispersion of active components. 展开更多
关键词 Al-containing yolk-shell silica particles accessibility ACIDITY Metal-support interaction Hydrodesulfurization
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Influence of Transportation Accessibility on Urban-rural Income Disparity and Its Spatial Heterogeneity
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作者 HUANG Xiaoyan KANG Chenchen +1 位作者 YIN Chun TANG Junqing 《Chinese Geographical Science》 SCIE CSCD 2024年第3期453-467,共15页
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 ... 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. 展开更多
关键词 transport accessibility income gap regional divergence spatial heterogeneity urban and rural areas China
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Measuring urban thermal environment from accessibility-based perspective:A case study in a populous city
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作者 Xinyu Dong Xiaoya Li +3 位作者 Yanmei Ye Dan Su Runjia Yang Angela Lausch 《Geography and Sustainability》 CSCD 2024年第3期329-342,共14页
Understanding the spatial interaction among residents,cooling service,and heat risk area in complex urban areas is conducive to developing targeted management.However,traditional urban thermal environment assessments ... Understanding the spatial interaction among residents,cooling service,and heat risk area in complex urban areas is conducive to developing targeted management.However,traditional urban thermal environment assessments typically relied on simple linear integration of associated indicators,often neglecting the spatial interaction effect.To explore the spatial interaction among the three elements,this study proposes an accessibility-based urban thermal environment assessment framework.Using Zhengzhou,a rapidly urbanizing city,as an example,remotely sensed images from three periods(2010,2015 and 2020)were applied to extract urban green space(UGS)and hot island area(HIA).An improved two-step floating catchment area(2SFCA)method and bivariate local Moran’s I were employed to explore whether residents’clustering locations are more likely to access cooling service or to be exposed to heat risk.The results demonstrate that the UGS in the city has been expanding,whereas the HIA shrank within the inner city in 2015 and then increased in 2020.Even though the urban thermal environment may have improved in the last decade,the spatial interaction among the residents,cooling service and heat risk area could be exacerbated.Spatial autocorrelation shows an increase in locations that are disadvantageous for resident congregation.Even when sufficient cooling services were provided,residents in these areas could still be exposed to high heat risk.The developed urban thermal environment framework provides a novel insight into the residents’heat risk exposure and cooling service accessibility,and the findings could assist urban planners in targeting the improvement of extra heat exposure risk locations. 展开更多
关键词 Urban heat island Urban green space accessibility Remote sensing Spatial autocorrelation analysis
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Accessibility and Fairness of Public Service Facilities from the Perspective of Supply and Demand Coordination: A Case Study of Old Urban Area of Guangzhou City
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作者 CHEN Xu LI Xin 《Journal of Landscape Research》 2024年第3期21-26,共6页
The accessibility and fairness of public service facilities are important manifestations of the convenience and equality of urban public service resource allocation.Optimizing the layout of urban public service facili... The accessibility and fairness of public service facilities are important manifestations of the convenience and equality of urban public service resource allocation.Optimizing the layout of urban public service facilities is an inevitable requirement for promoting the construction of people centered cities.This paper takes the old urban area of Guangzhou as the research area,measures the accessibility of multiple types of public service facilities based on an improved two-step floating catchment method,and combines Palma Ratio and location quotient methods to explore the fairness of urban public service facilities from two dimensions:social equity and spatial equity,with supply and demand relationship analysis as the main line.Research has shown that:①there is a significant spatial difference in the accessibility of public service facilities in the old urban areas of Guangzhou,and the comprehensive accessibility is generally higher in the central and southeastern regions of the old urban areas with fewer residential populations;②from the perspective of social equity,the resource allocation of public service facilities in the old urban areas of Guangzhou is in a seriously unfair state(with a fairness index of 2.99),and there are also varying degrees of unfairness within the streets;③from the perspective of spatial equity,the location quotient of public service facilities in the old urban areas of Guangzhou shows a pattern of multil center circles decreasing,indicating a significant spatial mismatch between the accessibility supply side of public service facilities and the demand side of the residential population.The research conclusion will provide scientific basis for optimizing the allocation of urban public service facilities and ensuring the equalization of public services. 展开更多
关键词 Public service facilities accessibility Social equity Space equity Guangzhou City
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Prevalence of Occupational Injury and Knowledge of Post-Exposure Prophylaxis Accessibility among Healthcare Workers in Mogadishu, Somalia
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作者 Yonis Abdullahi Ahmed Anshur Abdishakur Mohamud Sheik +10 位作者 Miski Abdullahi Roble Abdullahi Mohamed Yasin Abdullahi Ali Mohamed Fardowso Ali Mohamud Abdimalik Dahir Abdi Ikran Abdullahi Isse Warda Adan Ibrahim Mohamed Jimale Adan Ugbad Ahmed Daud Ahmed Aweis Abdullahi Mohamed Hassan Fujeyra 《Occupational Diseases and Environmental Medicine》 2024年第3期172-198,共27页
Introduction: Healthcare workers in Mogadishu, Somalia face significant occupational injury risks, particularly needle stick injuries, with 61.1% reporting incidents. This poses a serious threat to their health, leadi... Introduction: Healthcare workers in Mogadishu, Somalia face significant occupational injury risks, particularly needle stick injuries, with 61.1% reporting incidents. This poses a serious threat to their health, leading to infections such as hepatitis B, hepatitis C, and HIV. Despite the high prevalence of injuries, awareness of Post-Exposure Prophylaxis (PEP) accessibility is relatively high, with 84.0% of respondents aware of it. However, there are gaps in knowledge and implementation, as evidenced by variations in availability of PEP. Improving workplace safety measures, providing comprehensive training on injury prevention and PEP protocols, and ensuring consistent availability of PEP in healthcare facilities are crucial steps to safeguard the well-being of healthcare workers in Mogadishu, Somalia. Methods: A cross-sectional study was conducted among hospital workers in Mogadishu, Somalia, focusing on professionals from various healthcare facilities. The study targeted nurses, doctors, laboratory personnel, and pharmacists. Purposive sampling was employed, resulting in a sample size of 383 calculated using Fisher’s sample size formula. Data were collected using coded questionnaires entered into Microsoft Excel 2019 and analyzed with SPSS software to generate frequencies and proportions, presented through frequency tables and pie figures. Results: The study in Mogadishu, Somalia, examined the prevalence of occupational injuries and knowledge of Post-Exposure Prophylaxis (PEP) accessibility among healthcare workers. Findings indicate a high prevalence of injuries, with 61.1% reporting incidents, predominantly needle stick injuries (60.6%). Despite the majority seeking prompt medical attention (72.0%), work-related illnesses affected 53.2% of respondents, notably work-related stress (59.5%). While most received training on injury and illness prevention (68.9%), gaps exist in PEP awareness, with 16.0% unaware of it. Nonetheless, 84.0% were aware, predominantly through health facilities (52.0%). Availability of PEP was reported by 71.3% in healthcare facilities, with variations in shift availability. The majority reported guidelines for PEP use (55.7%). Efforts are needed to bolster PEP awareness and ensure consistent availability in healthcare facilities to safeguard worker health. Conclusion: High prevalence of occupational injuries among healthcare workers, with needle stick injuries being the most common (60.6%). Despite this, 84.0% of respondents were aware of Post-Exposure Prophylaxis (PEP), primarily learning about it from health facilities (52.0%). While 71.3% reported the availability of PEP in their facility, 28.7% noted its unavailability. These results emphasize the need for improved education and accessibility of PEP to mitigate occupational injury risks. 展开更多
关键词 Prevalence of Occupational Injury Post-Exposure Prophylaxis (PEP) accessibility Healthcare Workers Needle Stick Injuries Infections (Hepatitis B Hepatitis C HIV) Awareness KNOWLEDGE Workplace Safety PEP Availability Blood-Borne Diseases Personal Protective Equipment (PPE) HIV PEP (Post-Exposure Prophylaxis)
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Affordability, Accessibility, and Quality of Maternal Health Care Services and Level of Satisfaction of Mothers in Rural Areas in China
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作者 Teng Sun Rebecca A.Guariño 《Journal of Clinical and Nursing Research》 2024年第8期218-231,共14页
Objective:This study aimed to understand the affordability,accessibility,and quality of maternal and child health services for postpartum mothers,and their impact on satisfaction.Methods:The study utilized the Anderso... Objective:This study aimed to understand the affordability,accessibility,and quality of maternal and child health services for postpartum mothers,and their impact on satisfaction.Methods:The study utilized the Anderson model and revised the Maternal Pregnancy and Perinatal Health Service Questionnaire.A survey was conducted among 289 mothers aged 20–49 in Feicheng City.Results:Regarding accessibility,most respondents(133)reported that travel time to healthcare services exceeded 60 minutes,while 99 respondents indicated a travel time of 16–30 minutes.The issue of affordability was highlighted,with 86.85%of participants perceiving maternal healthcare services as costly,indicating a significant financial burden.More than 50%of respondents were satisfied with two specific dimensions(P<0.05)regarding the quality of maternal healthcare services.Conclusion:The study found that accessibility,affordability,and quality significantly affect mothers’satisfaction with maternal health services.Future research should focus on developing more suitable service pathways for rural mothers. 展开更多
关键词 AFFORDABILITY accessibility QUALITY Maternal health care services Level of satisfaction Rural area
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Study on the Influence of Lanzhou-Urumqi High-Speed Railway on Regional Accessibility and Economic Development
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作者 Lili Ma Xiaolong Han Miao Gong 《Proceedings of Business and Economic Studies》 2024年第2期22-31,共10页
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 accessibil... 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. 展开更多
关键词 Lanzhou-Urumqi high-speed railway Regional economy Double difference model accessibility model Empirical analysis
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GIS-Based Analysis to Identify the Distribution and Accessibility of Urban Green Space in Dhaka Metropolitan City, Bangladesh 被引量:1
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作者 Mohammad Wahidur Khan Md. Sazzad Hossain Mahbubul Alam 《Journal of Geographic Information System》 2023年第1期35-52,共18页
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 distributio... 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. 展开更多
关键词 URBANIZATION Urban Green Space accessibility Proxy Distance
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Accessibility and utilization of healthcare services among diabetic patients:Is diabetes a poor man’s ailment? 被引量:1
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作者 Chiedu Eseadi Amos Nnaemeka Amedu +2 位作者 Leonard Chidi Ilechukwu Millicent O Ngwu Osita Victor Ossai 《World Journal of Diabetes》 SCIE 2023年第10期1493-1501,共9页
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 t... 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. 展开更多
关键词 accessibility DIABETES Healthcare services Patients POVERTY
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A Blockchain-Based Access Control Scheme for Reputation Value Attributes of the Internet of Things 被引量:1
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作者 Hongliang Tian Junyuan Tian 《Computers, Materials & Continua》 SCIE EI 2024年第1期1297-1310,共14页
The Internet of Things(IoT)access controlmechanism may encounter security issues such as single point of failure and data tampering.To address these issues,a blockchain-based IoT reputation value attribute access cont... The Internet of Things(IoT)access controlmechanism may encounter security issues such as single point of failure and data tampering.To address these issues,a blockchain-based IoT reputation value attribute access control scheme is proposed.Firstly,writing the reputation value as an attribute into the access control policy,and then deploying the access control policy in the smart contract of the blockchain system can enable the system to provide more fine-grained access control;Secondly,storing a large amount of resources fromthe Internet of Things in Inter Planetary File System(IPFS)to improve system throughput;Finally,map resource access operations to qualification tokens to improve the performance of the access control system.Complete simulation experiments based on the Hyperledger Fabric platform.Fromthe simulation experimental results,it can be seen that the access control system can achieve more fine-grained and dynamic access control while maintaining high throughput and low time delay,providing sufficient reliability and security for access control of IoT devices. 展开更多
关键词 Blockchain IOT access control Hyperledger Fabric
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The impact of Internet access on household dietary quality:Evidence from rural China 被引量:1
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作者 Yi Cui Qiran Zhao +1 位作者 Thomas Glauben Wei Si 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期374-383,共10页
Over the past few decades,the Internet has rapidly diffused across China.The spread of the Internet has had a profound economic and social impact on Chinese rural areas.Existing research shows that Internet access sig... Over the past few decades,the Internet has rapidly diffused across China.The spread of the Internet has had a profound economic and social impact on Chinese rural areas.Existing research shows that Internet access significantly impacts agricultural production and improves smallholder farmers’income.Beyond these,the Internet can affect other dimensions of social welfare.However,research about the impact of Internet access on dietary quality in rural China remains scarce.This study utilizes multi-period panel data from Fixed Observation Point in rural China from 2009 to 2015 to estimate the impact of Internet access on dietary quality and food consumption of rural households and conducts a causal analysis.Regression models with time and household fixed effects allow robust estimation while reducing potential issues of unobserved heterogeneity.The estimates show that Internet access has significantly increased rural household dietary quality(measured by the Chinese Diet Balance Index).Further research finds that Internet access has increased the consumption of animal products,such as aquatic and dairy products.We also examine the underlying mechanisms.Internet access improves dietary quality and food consumption mainly through increasing household income and food expenditure.These results encourage the promotion of Internet access as a valuable tool for nutritional improvements,especially in rural areas. 展开更多
关键词 dietary quality fixed effect model Internet access rural China
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Detection of Turbulence Anomalies Using a Symbolic Classifier Algorithm in Airborne Quick Access Record(QAR)Data Analysis 被引量:1
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作者 Zibo ZHUANG Kunyun LIN +1 位作者 Hongying ZHANG Pak-Wai CHAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第7期1438-1449,共12页
As the risks associated with air turbulence are intensified by climate change and the growth of the aviation industry,it has become imperative to monitor and mitigate these threats to ensure civil aviation safety.The ... As the risks associated with air turbulence are intensified by climate change and the growth of the aviation industry,it has become imperative to monitor and mitigate these threats to ensure civil aviation safety.The eddy dissipation rate(EDR)has been established as the standard metric for quantifying turbulence in civil aviation.This study aims to explore a universally applicable symbolic classification approach based on genetic programming to detect turbulence anomalies using quick access recorder(QAR)data.The detection of atmospheric turbulence is approached as an anomaly detection problem.Comparative evaluations demonstrate that this approach performs on par with direct EDR calculation methods in identifying turbulence events.Moreover,comparisons with alternative machine learning techniques indicate that the proposed technique is the optimal methodology currently available.In summary,the use of symbolic classification via genetic programming enables accurate turbulence detection from QAR data,comparable to that with established EDR approaches and surpassing that achieved with machine learning algorithms.This finding highlights the potential of integrating symbolic classifiers into turbulence monitoring systems to enhance civil aviation safety amidst rising environmental and operational hazards. 展开更多
关键词 turbulence detection symbolic classifier quick access recorder data
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Dek219 encodes the DICER-LIKE1 protein that affects chromatin accessibility and kernel development in maize
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作者 XIE Si-di TIAN Ran +6 位作者 ZHANG Jun-jie LIU Han-mei LI Yang-ping HU Yu-feng YU Guo-wu HUANG Yu-bi LIU Ying-hong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第10期2961-2980,共20页
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 developmen... 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. 展开更多
关键词 MAIZE kernel development chromatin accessibility HISTONE miRNA
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Geostatistical Analysis of Accessibility to Secondary Schools in Parts of Benue State
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作者 David Sesugh Aule Mamman Saba Jibril Taye Oluwafemi Adewuyi 《Journal of Geographic Information System》 2023年第1期1-18,共18页
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 observ... 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. 展开更多
关键词 accessibility DISTANCE GIS GPS Service Quality Transportation Cost
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Accessibility Measures in Modal Choice Models: A Proof of Concept Applied to Freight Transport
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作者 Bart Jourquin 《Journal of Transportation Technologies》 2023年第1期38-60,共23页
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)reg... 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. 展开更多
关键词 Freight Transport Model Modal Choice accessibility ASSIGNMENT
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Spatial Accessibility of Emergency Facilities to Road Accident Victims in Federal Capital City
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作者 David Sesugh Aule Mamman Saba Jibril Badiatu Danladi Garba 《Journal of Geoscience and Environment Protection》 2023年第2期135-150,共16页
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 ... 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. 展开更多
关键词 ACCIDENT accessibility Emergency Facility RESCUE Geographic Information System (GIS)
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Chicken chromatin accessibility atlas accelerates epigenetic annotation of birds and gene fine-mapping associated with growth traits
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作者 Xiao-Ning Zhu Yu-Zhe Wang +3 位作者 Chong Li Han-Yu Wu Ran Zhang Xiao-Xiang Hu 《Zoological Research》 SCIE CAS CSCD 2023年第1期53-62,共10页
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 informat... 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. 展开更多
关键词 CHICKEN Chromatin accessibility atlas ATAC-seq Tissue-specific OCRs GWAS Growth traits
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Access数据库技术及其应用研究 被引量:1
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作者 侯培杰 《信息与电脑》 2024年第3期149-151,共3页
文章主要研究Access数据库技术及其应用,首先介绍Access数据库技术的理论基础,包括数据库结构、数据库安全性、数据库存储空间,然后探讨Access数据库技术的应用方法,包括数据存储和管理、报表生成和打印、数据库设计和开发等,最后对基于... 文章主要研究Access数据库技术及其应用,首先介绍Access数据库技术的理论基础,包括数据库结构、数据库安全性、数据库存储空间,然后探讨Access数据库技术的应用方法,包括数据存储和管理、报表生成和打印、数据库设计和开发等,最后对基于Access数据库的实例应用进行分析,展示Access数据库在提高工作效率、优化数据管理和增强决策能力等方面的作用。 展开更多
关键词 access 数据库技术 应用
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