This paper aims to explore the interactive impact between transportation systems and socio-economic development,employing Structural Equation Modeling(SEM)to analyze data from 31 provincial-level administrative region...This paper aims to explore the interactive impact between transportation systems and socio-economic development,employing Structural Equation Modeling(SEM)to analyze data from 31 provincial-level administrative regions in China from 2013 to 2022.It comprehensively considers key indicators from the economic,social,and transportation sectors.The paper constructs a model encompassing 5 latent variables and 15 observed variables.Through in-depth analysis,it reveals the promoting role of transportation systems on economic growth and social development,as well as the demand for transportation system construction and optimization driven by socio-economic development levels.The results indicate that an efficient transportation system can not only directly drive economic growth but also indirectly promote social development by improving social welfare and enhancing quality of life.This paper provides new insights into understanding the complex relationship between transportation systems and socio-economic development and holds significant implications for policymakers in optimizing transportation infrastructure to foster economic and social development.展开更多
Leaf color mutants in higher plants are considered to be ideal materials for studying the chlorophyll biosynthesis,photosynthesis mechanism and chloroplast development.Herein,we identified a spontaneous mutant,yc412,i...Leaf color mutants in higher plants are considered to be ideal materials for studying the chlorophyll biosynthesis,photosynthesis mechanism and chloroplast development.Herein,we identified a spontaneous mutant,yc412,in cultivated cucumber that exhibited yellow cotyledons.The yellow-lethal mutant was diagnosed with an abnormal chloroplast ultrastructure,and reduced photosynthetic capacity and pigment content.Through bulked segregant analysis-based whole-genome sequencing and fine genetic mapping,we narrowed the yellow cotyledons (yc) locus to a 96.8 kb interval on chromosome 3.By resequencing and molecular cloning,we showed that Csyc is a potential candidate gene,which encodes a yellow stripe-like (YSL) transporter.The T to C mutation in the promoter region of Csyc caused the yellow cotyledon phenotype in yc412.Compared to YZU027A (WT),the expression of Csyc was significantly downregulated in the cotyledons of yc412.Silencing of Csyc in cucumber via virus-induced gene silencing resulted in chlorotic leaves,mainly by suppressing the chlorophyll content.Furthermore,a comparative transcriptome analysis revealed that chloroplast-related genes and chlorophyll biosynthesis genes were significantly downregulated in yc412 cotyledons.Our results provide new insights into the molecular function of the YSL transporter in plant chloroplast development and chlorophyll synthesis.展开更多
Transportation infrastructure is crucial to China’s economic growth because it substantially contributes to the holistic development of rural primary,secondary,and tertiary industries.This study innovatively examines...Transportation infrastructure is crucial to China’s economic growth because it substantially contributes to the holistic development of rural primary,secondary,and tertiary industries.This study innovatively examines transportation infrastructure and urbanization levels to explore,both theoretically and empirically,their relationship with the holistic development of primary,secondary,and tertiary industries in rural China,and the mediating role of urbanization on this relationship.We employed fixed-effects models,the entropy weight approach,mixed regression,and generalized method of moments to analyze the data of 30 provinces across China from 2013 to 2020.The results indicate that the construction of transportation infrastructure directly fosters the collective advancement of such industries in rural areas and that urbanization partially mediates the transportation infrastructure-rural industry integration relationship.However,the western region shows disparities in the integrated development of these sectors.Further analysis reveals that foreign investments amplify the positive influence of transportation infrastructure on rural industry integration.Essentially,the enhancement of rural transportation infrastructure,promotion of urbanization,implementation of strategic planning,and strengthening of support mechanisms are crucial aspects in the comprehensive development of rural industries and the achievement of rural revitalization in China.展开更多
Scientific development is an invaluable asset to a country.Policies and development modes should be carried out based on scientific findings not only in industry,but also in transportation infrastructure construction....Scientific development is an invaluable asset to a country.Policies and development modes should be carried out based on scientific findings not only in industry,but also in transportation infrastructure construction.Building an integrated transportation system,which is in line with the national requirements of China and supports sustainable socio-economic development,is a key strategic issue related to building a moderately prosperous society and achieving realistic goals of a medium-level developed country.Based on a systematic review of the advances in China's transportation infrastructure over the last 60 years,this paper explores the main drivers of transportation development,including national policy,transportation structure,investment efficiency,and technological innovation.Analysis shows that China's comprehensive transportation infrastructure construction since 1949 can be divided into five stages initiated by these drivers,which correspond to four transition modes:policy transition,structural transition,efficiency transition,and technology transition.The transition path of China's transportation development shows that the dominant factors have changed,and the interval for each transition has shortened.With the implementation of the '12th Five-Year Plan',China's transportation infrastructure construction is showing some new characteristics and facing a new development transition.Finally,this paper analyzes the trends in transportation development in China and concludes that technological innovation will be the main driving force to increase the transportation supply and service area in the future.展开更多
Polar auxin transport (PAT) is critical in plant growth and development, especially polar differentiation and pattern formation. Lots of studies have been performed in dicots while relative less in monocots. Using two...Polar auxin transport (PAT) is critical in plant growth and development, especially polar differentiation and pattern formation. Lots of studies have been performed in dicots while relative less in monocots. Using two kinds of PAT inhibitors, 2, 3, 5-triiodobenzoic acid (TIBA) and 9-hydroxyfluorene-9-carboxylic acid (HFCA), it was shown that PAT is important for rice (Oryza sativa L. cv. Zhonghua 11) root development, including elongation of the primary roots, initiation and elongation of lateral roots, and formation of adventitious roots. Inhibition of PAT resulted in the shortened primary roots, less and shortened lateral and adventitious roots. Exogenously supplemented NAA can partially rescue the formation of adventitious roots but not lateral roots, while low concentration of NAA (0.1 mumol/L) could not rescue either of them, suggesting the possible different mechanisms of lateral and adventitious root initiations. Treatment of 30 mumol/L TIBA did not completely inhibit the initiation of lateral roots, and survival capacities of which were demonstrated through cross section experiments revealing the presence of primordial of lateral roots at different stages. Further studies through localized application of PAT inhibitors indicated that auxin flow, transported from coleoptiles to the base, is not only responsible for the auxin contents in stem nodes but also critical for initiation and elongation of adventitious roots.展开更多
The coordinated development is the core of sustainable development and the hot issue of international research.Inland water transport(IWT) is an important part of the water resources exploiting system and comprehensiv...The coordinated development is the core of sustainable development and the hot issue of international research.Inland water transport(IWT) is an important part of the water resources exploiting system and comprehensive transport system under socio-economic context of river basin,and also the country's sustainable development priorities to achieve resource-conserving and environment-friendly strategy.Based on the coordinated development content,the paper combined Germany's successful development experience,explored the elements and problem of the coordinated development of IWT system of China's national economic strategy and basin economy,water resourse system,comprehensive transport system,and system itself,and their countermeasures and suggestions,in order to facilitate rapid and coordinated development of China's inland water transport.展开更多
The anther cuticle and pollen exine play a critical role in male gametophyte development. The sporopollenin precursors and cuticular lipid monomers are transported to the surface of the microspores and the epidermis b...The anther cuticle and pollen exine play a critical role in male gametophyte development. The sporopollenin precursors and cuticular lipid monomers are transported to the surface of the microspores and the epidermis by lipid transport proteins(LTPs) and ATP-binding cassette G(ABCG) transporters for the formation of the pollen wall and anther cuticle, respectively. However, the function of ABCG transporters in maize anther development is unclear. Here, we cloned the MS2 gene from the maize male sterile2 mutant using map-based cloning and determined that it encodes an ABCG transporter. MS2 protein was experimentally confirmed to be located on the cell membrane. The quantitative real-time PCR(qRT-PCR)results showed that MS2 was ubiquitously expressed in all vegetative and reproductive tissues, whereas a high transcriptional level of MS2 was observed in anthers, especially at the young microspore stage. Gas chromatography-mass spectrometry(GC–MS) analysis showed decreased accumulation of cutin and wax components in ms2 anthers, indicating that MS2 plays a role in the transport of lipid molecules to anther cuticle and pollen exine. To our knowledge, MS2 is the first reported ABCG transporter gene that participates in anther development in maize.展开更多
Considerable changes have taken place in commercial passenger air transport since the enactment of the 1978 Airline Deregulation Act in the US and the deregulation of airline networks that has occurred elsewhere. The ...Considerable changes have taken place in commercial passenger air transport since the enactment of the 1978 Airline Deregulation Act in the US and the deregulation of airline networks that has occurred elsewhere. The commercial and operational freedoms have led most of the larger carriers to develop hub-and-spoke networks, within which certain cities or metropolitan areas emerge as key nodes possessing tremendous advantages over other locations in the air transport system. This paper examines the nature of hub-and-spoke operations in air transportation services, and the benefits that accrue to a city or geographical region that is host to an airline hub. In particular, it looks into linkages between the air service hub and local economic development. Four potential types of impact of airports on the regional economy are defined and discussed. As an example, the assessment of the economic impacts of Cincinnati-Northern Kentucky International Airport (CVG), a major Delta Airlines hub, is introduced.展开更多
The economic benefits of transport infrastructure investment have been widely accepted.However,the varying influence of road transport development across vertical space has rarely been discussed.Taking Sichuan provinc...The economic benefits of transport infrastructure investment have been widely accepted.However,the varying influence of road transport development across vertical space has rarely been discussed.Taking Sichuan province in China as case study area where the landform is diverse and complex,administrative counties were categorized into 4 main types:plain counties,hill counties,mountain counties,and plateau counties.Using statistical data during 2006-2014,theperformanceofeconomic development and transport construction level in the four types of counties are discussed.Subsequently,the heterogeneous effect of each grade road on economy was calculated by local regression model(GWR).The results indicate that plain counties largely surpassed the other geomorphic counties in economic development level,while the gradient gap among them was on the decline.Similarly,distribution of transport infrastructure presented a decreasing trend from the low plain counties to high plateau counties.Regional imbalances were mainly reflected in the County road and Village road.Regarding the changes of regional gaps,National&Provincial roads and County roads were constantly expanding,whereas the disparity of Village road was slowly narrowing over time.Particularly noteworthy was the non-stationary economic influence of traffic factors across vertical gradients.On average,National&Provincial roads generated higher benefits in the high elevation regions than the lowlands.In contrast,County road and Village road were found to be more effective in promoting economic development in plains.With regard to local estimates of traffic factors,coefficients in mountain counties exhibited larger fluctuation ranges than other geomorphic units.The conclusions provide a basis for government decisionmaking in a more reasonable construction arrangement of road facilities and sustainable economic development.展开更多
With the development of the city and the increase of the population, the de<span style="font-family:Verdana;">mand for transportation is increasing. The increases in transportation ways </span>&l...With the development of the city and the increase of the population, the de<span style="font-family:Verdana;">mand for transportation is increasing. The increases in transportation ways </span><span style="font-family:Verdana;">and demand have also brought certain energy and environmental problems t</span><span style="font-family:Verdana;">o transportati</span><span style="font-family:Verdana;">on construction. A good transportation environment and green travel experience have an important role in promoting the happiness of urban lif</span><span style="font-family:Verdana;">e and the sustainable development of society. Based on this, the follo</span><span style="font-family:Verdana;">wing solutions are proposed for the construction and development of urban green </span><span style="font-family:Verdana;">transportation. First, as a guiding role, the government should formulate active transportation and green transportation policies to promote the reform of multiple p</span><span style="font-family:Verdana;">ublic transportation methods. Second, as a leading role, the market can support a variety of the construction of green travel modes, which could encourage the development of shared bicycles and new energy vehicles. Third, </span><span style="font-family:Verdana;">as the main role of city, the citizens would like to choose green travel tools wi</span><span style="font-family:Verdana;">th the guid</span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">ance</span></span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> in the conscious level. If we built green behavior into a fashionable business card of the city, green behavior will lead the city’s transportation construction and development.</span></span></span></span></span>展开更多
Transportation planning is a critical component for creating an orderly,intensive,and sustainable pattern of land development.By comprehensively considering the potential and suitability of transport construction,a co...Transportation planning is a critical component for creating an orderly,intensive,and sustainable pattern of land development.By comprehensively considering the potential and suitability of transport construction,a comprehensive method combining resources and environmental carrying capacity(RECC)and land development suitability(LDS)was developed by using techniques of GIS,analytic hierarchy process(AHP)and threedimensional magic cube.Taking Aba prefecture in Sichuan Province of Southwest China as a case study,LDS for transportation was analyzed from three aspects,including overall planning layout,different transport modes,and transportation projects.The results showed that the transport planning scales of most counties in Aba were suitable,and the order of LDS of different transport modes was railway>highway=superhighway>tourism track,which already included 42 new transportation projects.We found that two counties(Maoxian County and Jiuzhaigou County)should improve the ecological protection level of transportation,in which the railway network construction should be encouraged,and some transportation projects with low LDS should be postponed or constructed harmlessly.We suggest the combination of RECC and LDS for transportation could enhance the territorial space optimization and sustainable transport construction.展开更多
Based on the China Global Investment Tracker(CGIT)database of 2005-2018,this paper creates a country-sector-year panel set for a study on the BRI’s investment effects on the transportation sector of BRI countries usi...Based on the China Global Investment Tracker(CGIT)database of 2005-2018,this paper creates a country-sector-year panel set for a study on the BRI’s investment effects on the transportation sector of BRI countries using the difference-in-differencesin-differences(DDD)method.Our study finds that the BRI has significantly increased transportation investments by Chinese companies in the BRI countries without causing significant rise in problem transactions.The"debt trap"narrative that the BRI aims to take control over host countries’sovereign rights in exchange for debt write-offs is not supported by evidence.Discussions on sub-samples reveal that the BRI has mainly propelled SOEs in making transportation investments to generate development effects in host countries,most of which are Asian countries,and that the preferred mode of investment is cross-border M&As.展开更多
Based on the study on the city transport systems of some typical cities worldwide,this paper put forward that each city transport system has its own development mode,which is influenced by the city development plan,ec...Based on the study on the city transport systems of some typical cities worldwide,this paper put forward that each city transport system has its own development mode,which is influenced by the city development plan,economic development level,traveling vehicle composition etc..When some problems occur,such as the congestions caused by contradiction between the road capacity and vehicle composition,the city transport system may come into temporary maturity period.If the improvement for road system is limited meanwhile,optimized structure of vehicle composition should be an effective solution in this case.With the development of economy-internationalization,the development speed of city transport modernization is rapid.When traveling easiness is conflicting with efficiency,the advantages of public transport system become more obvious.Correspondingly,the superiority of two-wheel vehicles will reappear.Though the important function of two-wheel vehicles for alleviating city traffic problems is obvious,however,their development strategy must be reasonably proposed,and operation regulations must be performed accordingly.展开更多
Since the 1960s, Hong Kongs new towns have been builton the assumption that they could be socially and economically selfcontained entities. A study of the linkage between three new townsand metropolitan area confirms ...Since the 1960s, Hong Kongs new towns have been builton the assumption that they could be socially and economically selfcontained entities. A study of the linkage between three new townsand metropolitan area confirms that substantial commuting trips arestill made. The new towns serve as dormitories for people workingin the metropolitan area. The commuters' reliance on publictransport is significant. The towns are thus far from self-containedeven aller 20 years of development. The public transport network,trip rate, peak factor, purpose, mode choice, costs and journey time,are signilicantly different from those originally estimated. Thesemay be related to distance from the metropolitan area,theavailability of modes, the structure of the public transport netwrk,and changs in the economical structure of Hong Kong. lt suggeststhat the direct and indiscriminant importation of Westernplanning practice to plan new towns with an oriental socio-economicsetting deserves critical review.展开更多
Traffic is a function of land use. Based on the understanding of mutual influences between transportation investment and land development, transportation corridors of various levels in Great Chengdu Area (GCA) were ...Traffic is a function of land use. Based on the understanding of mutual influences between transportation investment and land development, transportation corridors of various levels in Great Chengdu Area (GCA) were investigated. Trip generation was predicted based on population expansion, and trip attraction was estimated based on land use intensity coefficient. Lane assignment of transportation corridors with case studies is expected with two-way-six-lane routes connecting county-cities, two-way-four-lane routes connecting new towns in plane area, and two-way-two-lane connecting new towns in hilly area and prime villages.展开更多
Firstly, the development background of Ningbo Transportation Port & Shipping Industry is analyzed on a spatial scale. Based on that, the strategic goal of Ningbo transportation port Port & Shipping Industry is...Firstly, the development background of Ningbo Transportation Port & Shipping Industry is analyzed on a spatial scale. Based on that, the strategic goal of Ningbo transportation port Port & Shipping Industry is put forward, and strategic path analysis of strategic objectives is carried out. Finally, with the dynamic resource view, the strategic integration model of Ningbo Port & Shipping Industry is proposed.展开更多
The objective of this paper is to create a process view of the development of intermodal transport solution from the basic idea to implementation. Special case of dedicated solutions based on large shippers’ volumes ...The objective of this paper is to create a process view of the development of intermodal transport solution from the basic idea to implementation. Special case of dedicated solutions based on large shippers’ volumes is chosen, where the shippers engage in the development process of the new solutions. Research is conducted using a qualitative approach: multiple case studies. Empirical data has been obtained through in-depth semi-structured interviews with relevant respondents involved in the development projects. Shippers’ perspective on the development process is studied. Development process can be described through a generic four-stage process: Initiation, Planning, Implementation, and Further Development. Different actors and different resources are required at the different stages. The complex process of establishing new intermodal solutions has lacked attention in the intermodal research. Understanding and improving the development process of new intermodal solutions is considered to have an important effect on the viability of intermodal transport and can help to understand the barriers that prevent companies from switching to intermodal. Development process of new dedicated intermodal solutions is a gradual process of building up the transport solution in a continuous interaction between shippers and transport service providers. Research has focused on the shipper perspective on inter-modal transport, showing that switching to an intermodal transport is not simply a mode choice issue, but involves a transition process that takes time, demands resources, cooperation/coordination between multiple parties, may require changes in the supply chain beyond the transport link, involves multiple actors, and involves an industry that is itself in a process of change.展开更多
To investigate the spatial synergy between agricultural development level and transport superiority degree in grain-producing areas of the central Jilin Province and the driving mechanism between them,22 counties in t...To investigate the spatial synergy between agricultural development level and transport superiority degree in grain-producing areas of the central Jilin Province and the driving mechanism between them,22 counties in the central Jilin Province were used as the research units to calculate agricultural development level and transport superiority degree using the entropy weighting method,weighted travel time and raster cost distance.The spatial econometric model was used to analyze the mechanism of the mutual influence between the two.The main conclusions are as follows.1)Agricultural development level around Changchun,the provincial capital city,and in the areas of Changchun-Jilin and Changchun-Gongzhuling is high,whereas the development level of the counties in the southwest is low.2)Transport superiority degree of each county has improved,the overall connectivity of the road networks has been optimized,and the level of transportation accessibility has shown the development trend of‘centralization’,exhibiting the characteristics of proximity diffusion.3)Locally,there is spatial heterogeneity in the mutual driving effects of the two,with six main patterns.4)The theoretical conditions of von Thunen’s agricultural location have changed under the conditions of market economy due to the improvement of the transport networks,the new model of agricultural development,and the changes of the market system.展开更多
The rise of the edible fungus industry has not only greatly increased the income of Chinese farmers,but also promoted the economic,social and ecological development of rural areas.Through a survey of the edible fungus...The rise of the edible fungus industry has not only greatly increased the income of Chinese farmers,but also promoted the economic,social and ecological development of rural areas.Through a survey of the edible fungus industry in Heilongjiang Province,it found problems such as insufficient standardized production bases,insufficient coverage of"Internet+edible fungi",weak industrial clusters,conservative management ideas,and lack of professional talents.The development potential of edible fungi was analyzed and reasonable recommendations were put forward to promote the healthy,efficient and sustainable development of the edible fungus industry in Heilongjiang Province.展开更多
The characteristics of highway transport and the application of information technology in highway transport service are combined; the information flows' promotion and substitution on highway transport are analyzed; a...The characteristics of highway transport and the application of information technology in highway transport service are combined; the information flows' promotion and substitution on highway transport are analyzed; and the highway transport development strategy based on information flow impact is proposed.展开更多
文摘This paper aims to explore the interactive impact between transportation systems and socio-economic development,employing Structural Equation Modeling(SEM)to analyze data from 31 provincial-level administrative regions in China from 2013 to 2022.It comprehensively considers key indicators from the economic,social,and transportation sectors.The paper constructs a model encompassing 5 latent variables and 15 observed variables.Through in-depth analysis,it reveals the promoting role of transportation systems on economic growth and social development,as well as the demand for transportation system construction and optimization driven by socio-economic development levels.The results indicate that an efficient transportation system can not only directly drive economic growth but also indirectly promote social development by improving social welfare and enhancing quality of life.This paper provides new insights into understanding the complex relationship between transportation systems and socio-economic development and holds significant implications for policymakers in optimizing transportation infrastructure to foster economic and social development.
基金supported by the the“JBGS”Project of Seed Industry Revitalization in Jiangsu Province,China(JBGS[2021]018)the Jiangsu Agricultural Innovation of New Cultivars,China(PZCZ201720)the Open Project Program of Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement,China(K2020030)。
文摘Leaf color mutants in higher plants are considered to be ideal materials for studying the chlorophyll biosynthesis,photosynthesis mechanism and chloroplast development.Herein,we identified a spontaneous mutant,yc412,in cultivated cucumber that exhibited yellow cotyledons.The yellow-lethal mutant was diagnosed with an abnormal chloroplast ultrastructure,and reduced photosynthetic capacity and pigment content.Through bulked segregant analysis-based whole-genome sequencing and fine genetic mapping,we narrowed the yellow cotyledons (yc) locus to a 96.8 kb interval on chromosome 3.By resequencing and molecular cloning,we showed that Csyc is a potential candidate gene,which encodes a yellow stripe-like (YSL) transporter.The T to C mutation in the promoter region of Csyc caused the yellow cotyledon phenotype in yc412.Compared to YZU027A (WT),the expression of Csyc was significantly downregulated in the cotyledons of yc412.Silencing of Csyc in cucumber via virus-induced gene silencing resulted in chlorotic leaves,mainly by suppressing the chlorophyll content.Furthermore,a comparative transcriptome analysis revealed that chloroplast-related genes and chlorophyll biosynthesis genes were significantly downregulated in yc412 cotyledons.Our results provide new insights into the molecular function of the YSL transporter in plant chloroplast development and chlorophyll synthesis.
基金supported by 2023 Chongqing Education Commission Humanities and Social Sciences Research Planning Project[Grant No.23SKGH090]2023−2024 Higher Education Science Research Project of Chongqing Higher Education Association[Grant No.cqgj23037C].
文摘Transportation infrastructure is crucial to China’s economic growth because it substantially contributes to the holistic development of rural primary,secondary,and tertiary industries.This study innovatively examines transportation infrastructure and urbanization levels to explore,both theoretically and empirically,their relationship with the holistic development of primary,secondary,and tertiary industries in rural China,and the mediating role of urbanization on this relationship.We employed fixed-effects models,the entropy weight approach,mixed regression,and generalized method of moments to analyze the data of 30 provinces across China from 2013 to 2020.The results indicate that the construction of transportation infrastructure directly fosters the collective advancement of such industries in rural areas and that urbanization partially mediates the transportation infrastructure-rural industry integration relationship.However,the western region shows disparities in the integrated development of these sectors.Further analysis reveals that foreign investments amplify the positive influence of transportation infrastructure on rural industry integration.Essentially,the enhancement of rural transportation infrastructure,promotion of urbanization,implementation of strategic planning,and strengthening of support mechanisms are crucial aspects in the comprehensive development of rural industries and the achievement of rural revitalization in China.
基金Under the auspices of National Natural Science Foundation of China(No.41171107,41001082)Programme of Bingwei Excellent Young Scientists of Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences
文摘Scientific development is an invaluable asset to a country.Policies and development modes should be carried out based on scientific findings not only in industry,but also in transportation infrastructure construction.Building an integrated transportation system,which is in line with the national requirements of China and supports sustainable socio-economic development,is a key strategic issue related to building a moderately prosperous society and achieving realistic goals of a medium-level developed country.Based on a systematic review of the advances in China's transportation infrastructure over the last 60 years,this paper explores the main drivers of transportation development,including national policy,transportation structure,investment efficiency,and technological innovation.Analysis shows that China's comprehensive transportation infrastructure construction since 1949 can be divided into five stages initiated by these drivers,which correspond to four transition modes:policy transition,structural transition,efficiency transition,and technology transition.The transition path of China's transportation development shows that the dominant factors have changed,and the interval for each transition has shortened.With the implementation of the '12th Five-Year Plan',China's transportation infrastructure construction is showing some new characteristics and facing a new development transition.Finally,this paper analyzes the trends in transportation development in China and concludes that technological innovation will be the main driving force to increase the transportation supply and service area in the future.
文摘Polar auxin transport (PAT) is critical in plant growth and development, especially polar differentiation and pattern formation. Lots of studies have been performed in dicots while relative less in monocots. Using two kinds of PAT inhibitors, 2, 3, 5-triiodobenzoic acid (TIBA) and 9-hydroxyfluorene-9-carboxylic acid (HFCA), it was shown that PAT is important for rice (Oryza sativa L. cv. Zhonghua 11) root development, including elongation of the primary roots, initiation and elongation of lateral roots, and formation of adventitious roots. Inhibition of PAT resulted in the shortened primary roots, less and shortened lateral and adventitious roots. Exogenously supplemented NAA can partially rescue the formation of adventitious roots but not lateral roots, while low concentration of NAA (0.1 mumol/L) could not rescue either of them, suggesting the possible different mechanisms of lateral and adventitious root initiations. Treatment of 30 mumol/L TIBA did not completely inhibit the initiation of lateral roots, and survival capacities of which were demonstrated through cross section experiments revealing the presence of primordial of lateral roots at different stages. Further studies through localized application of PAT inhibitors indicated that auxin flow, transported from coleoptiles to the base, is not only responsible for the auxin contents in stem nodes but also critical for initiation and elongation of adventitious roots.
基金German BMBF(No. APR10 /810)Hunan Social Science Fund key Project(No. 12ZDB04)+1 种基金Innovation Group Foundation of China Education Department(No. IRT0916)International Project in Hunan Province(No. 2010WK3041)
文摘The coordinated development is the core of sustainable development and the hot issue of international research.Inland water transport(IWT) is an important part of the water resources exploiting system and comprehensive transport system under socio-economic context of river basin,and also the country's sustainable development priorities to achieve resource-conserving and environment-friendly strategy.Based on the coordinated development content,the paper combined Germany's successful development experience,explored the elements and problem of the coordinated development of IWT system of China's national economic strategy and basin economy,water resourse system,comprehensive transport system,and system itself,and their countermeasures and suggestions,in order to facilitate rapid and coordinated development of China's inland water transport.
基金supported by the Fundamental Research Funds for Central Non-Profit of Institute of Crop Sciences, Chinese Academy of Agricultural Sciences (S2018QY07)National Major Project for Transgenic Organism Breeding (2016ZX08010-004)。
文摘The anther cuticle and pollen exine play a critical role in male gametophyte development. The sporopollenin precursors and cuticular lipid monomers are transported to the surface of the microspores and the epidermis by lipid transport proteins(LTPs) and ATP-binding cassette G(ABCG) transporters for the formation of the pollen wall and anther cuticle, respectively. However, the function of ABCG transporters in maize anther development is unclear. Here, we cloned the MS2 gene from the maize male sterile2 mutant using map-based cloning and determined that it encodes an ABCG transporter. MS2 protein was experimentally confirmed to be located on the cell membrane. The quantitative real-time PCR(qRT-PCR)results showed that MS2 was ubiquitously expressed in all vegetative and reproductive tissues, whereas a high transcriptional level of MS2 was observed in anthers, especially at the young microspore stage. Gas chromatography-mass spectrometry(GC–MS) analysis showed decreased accumulation of cutin and wax components in ms2 anthers, indicating that MS2 plays a role in the transport of lipid molecules to anther cuticle and pollen exine. To our knowledge, MS2 is the first reported ABCG transporter gene that participates in anther development in maize.
基金Under the auspices of Intramural Research Incentive Grant from the Office of the Senior Vice President for Research atUniversity of Louisville
文摘Considerable changes have taken place in commercial passenger air transport since the enactment of the 1978 Airline Deregulation Act in the US and the deregulation of airline networks that has occurred elsewhere. The commercial and operational freedoms have led most of the larger carriers to develop hub-and-spoke networks, within which certain cities or metropolitan areas emerge as key nodes possessing tremendous advantages over other locations in the air transport system. This paper examines the nature of hub-and-spoke operations in air transportation services, and the benefits that accrue to a city or geographical region that is host to an airline hub. In particular, it looks into linkages between the air service hub and local economic development. Four potential types of impact of airports on the regional economy are defined and discussed. As an example, the assessment of the economic impacts of Cincinnati-Northern Kentucky International Airport (CVG), a major Delta Airlines hub, is introduced.
基金supported by the National Natural Science Foundation of China (Grants No. 41571523 and 41661144038)the National Basic Research Program of China (973 Program) (Grant No. 2013CBA01808)the National Key Technology Research and Development Program of the Ministry of Science and Technology of China (Grant No. 2014BAC05B01)
文摘The economic benefits of transport infrastructure investment have been widely accepted.However,the varying influence of road transport development across vertical space has rarely been discussed.Taking Sichuan province in China as case study area where the landform is diverse and complex,administrative counties were categorized into 4 main types:plain counties,hill counties,mountain counties,and plateau counties.Using statistical data during 2006-2014,theperformanceofeconomic development and transport construction level in the four types of counties are discussed.Subsequently,the heterogeneous effect of each grade road on economy was calculated by local regression model(GWR).The results indicate that plain counties largely surpassed the other geomorphic counties in economic development level,while the gradient gap among them was on the decline.Similarly,distribution of transport infrastructure presented a decreasing trend from the low plain counties to high plateau counties.Regional imbalances were mainly reflected in the County road and Village road.Regarding the changes of regional gaps,National&Provincial roads and County roads were constantly expanding,whereas the disparity of Village road was slowly narrowing over time.Particularly noteworthy was the non-stationary economic influence of traffic factors across vertical gradients.On average,National&Provincial roads generated higher benefits in the high elevation regions than the lowlands.In contrast,County road and Village road were found to be more effective in promoting economic development in plains.With regard to local estimates of traffic factors,coefficients in mountain counties exhibited larger fluctuation ranges than other geomorphic units.The conclusions provide a basis for government decisionmaking in a more reasonable construction arrangement of road facilities and sustainable economic development.
文摘With the development of the city and the increase of the population, the de<span style="font-family:Verdana;">mand for transportation is increasing. The increases in transportation ways </span><span style="font-family:Verdana;">and demand have also brought certain energy and environmental problems t</span><span style="font-family:Verdana;">o transportati</span><span style="font-family:Verdana;">on construction. A good transportation environment and green travel experience have an important role in promoting the happiness of urban lif</span><span style="font-family:Verdana;">e and the sustainable development of society. Based on this, the follo</span><span style="font-family:Verdana;">wing solutions are proposed for the construction and development of urban green </span><span style="font-family:Verdana;">transportation. First, as a guiding role, the government should formulate active transportation and green transportation policies to promote the reform of multiple p</span><span style="font-family:Verdana;">ublic transportation methods. Second, as a leading role, the market can support a variety of the construction of green travel modes, which could encourage the development of shared bicycles and new energy vehicles. Third, </span><span style="font-family:Verdana;">as the main role of city, the citizens would like to choose green travel tools wi</span><span style="font-family:Verdana;">th the guid</span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">ance</span></span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> in the conscious level. If we built green behavior into a fashionable business card of the city, green behavior will lead the city’s transportation construction and development.</span></span></span></span></span>
基金funded by Key Scientific Research Project of the Ministry of Transport(No.2020-MS4113)Scientific and Technological Development Project,Transport Planning and Research Institute of the Ministry of Transport(No.092117-434)Science and Technology Project of Henan Provincial Department of Transport(No.2020G-2-15)。
文摘Transportation planning is a critical component for creating an orderly,intensive,and sustainable pattern of land development.By comprehensively considering the potential and suitability of transport construction,a comprehensive method combining resources and environmental carrying capacity(RECC)and land development suitability(LDS)was developed by using techniques of GIS,analytic hierarchy process(AHP)and threedimensional magic cube.Taking Aba prefecture in Sichuan Province of Southwest China as a case study,LDS for transportation was analyzed from three aspects,including overall planning layout,different transport modes,and transportation projects.The results showed that the transport planning scales of most counties in Aba were suitable,and the order of LDS of different transport modes was railway>highway=superhighway>tourism track,which already included 42 new transportation projects.We found that two counties(Maoxian County and Jiuzhaigou County)should improve the ecological protection level of transportation,in which the railway network construction should be encouraged,and some transportation projects with low LDS should be postponed or constructed harmlessly.We suggest the combination of RECC and LDS for transportation could enhance the territorial space optimization and sustainable transport construction.
基金supported by the National Natural Science Foundation of China(NSFC)Youth Program“Study on the Diffusion Mechanism and Policy Effects of Local Environmental Management Policies:an Example of the‘River Chief System’”(Grant No.:71903085)the National Social Science Foundation of China Key Research Program“Study on BRI Trade and Investment Liberalization and Facilitation:Quantitative Evaluation and Implementation Strategies”(Grant No.:18VDL014)”the National Social Science Foundation of China Key Program“Study on China’s Economic Growth Potentials and Drivers”(Grant No.:14ZDA023)。
文摘Based on the China Global Investment Tracker(CGIT)database of 2005-2018,this paper creates a country-sector-year panel set for a study on the BRI’s investment effects on the transportation sector of BRI countries using the difference-in-differencesin-differences(DDD)method.Our study finds that the BRI has significantly increased transportation investments by Chinese companies in the BRI countries without causing significant rise in problem transactions.The"debt trap"narrative that the BRI aims to take control over host countries’sovereign rights in exchange for debt write-offs is not supported by evidence.Discussions on sub-samples reveal that the BRI has mainly propelled SOEs in making transportation investments to generate development effects in host countries,most of which are Asian countries,and that the preferred mode of investment is cross-border M&As.
文摘Based on the study on the city transport systems of some typical cities worldwide,this paper put forward that each city transport system has its own development mode,which is influenced by the city development plan,economic development level,traveling vehicle composition etc..When some problems occur,such as the congestions caused by contradiction between the road capacity and vehicle composition,the city transport system may come into temporary maturity period.If the improvement for road system is limited meanwhile,optimized structure of vehicle composition should be an effective solution in this case.With the development of economy-internationalization,the development speed of city transport modernization is rapid.When traveling easiness is conflicting with efficiency,the advantages of public transport system become more obvious.Correspondingly,the superiority of two-wheel vehicles will reappear.Though the important function of two-wheel vehicles for alleviating city traffic problems is obvious,however,their development strategy must be reasonably proposed,and operation regulations must be performed accordingly.
文摘Since the 1960s, Hong Kongs new towns have been builton the assumption that they could be socially and economically selfcontained entities. A study of the linkage between three new townsand metropolitan area confirms that substantial commuting trips arestill made. The new towns serve as dormitories for people workingin the metropolitan area. The commuters' reliance on publictransport is significant. The towns are thus far from self-containedeven aller 20 years of development. The public transport network,trip rate, peak factor, purpose, mode choice, costs and journey time,are signilicantly different from those originally estimated. Thesemay be related to distance from the metropolitan area,theavailability of modes, the structure of the public transport netwrk,and changs in the economical structure of Hong Kong. lt suggeststhat the direct and indiscriminant importation of Westernplanning practice to plan new towns with an oriental socio-economicsetting deserves critical review.
文摘Traffic is a function of land use. Based on the understanding of mutual influences between transportation investment and land development, transportation corridors of various levels in Great Chengdu Area (GCA) were investigated. Trip generation was predicted based on population expansion, and trip attraction was estimated based on land use intensity coefficient. Lane assignment of transportation corridors with case studies is expected with two-way-six-lane routes connecting county-cities, two-way-four-lane routes connecting new towns in plane area, and two-way-two-lane connecting new towns in hilly area and prime villages.
文摘Firstly, the development background of Ningbo Transportation Port & Shipping Industry is analyzed on a spatial scale. Based on that, the strategic goal of Ningbo transportation port Port & Shipping Industry is put forward, and strategic path analysis of strategic objectives is carried out. Finally, with the dynamic resource view, the strategic integration model of Ningbo Port & Shipping Industry is proposed.
文摘The objective of this paper is to create a process view of the development of intermodal transport solution from the basic idea to implementation. Special case of dedicated solutions based on large shippers’ volumes is chosen, where the shippers engage in the development process of the new solutions. Research is conducted using a qualitative approach: multiple case studies. Empirical data has been obtained through in-depth semi-structured interviews with relevant respondents involved in the development projects. Shippers’ perspective on the development process is studied. Development process can be described through a generic four-stage process: Initiation, Planning, Implementation, and Further Development. Different actors and different resources are required at the different stages. The complex process of establishing new intermodal solutions has lacked attention in the intermodal research. Understanding and improving the development process of new intermodal solutions is considered to have an important effect on the viability of intermodal transport and can help to understand the barriers that prevent companies from switching to intermodal. Development process of new dedicated intermodal solutions is a gradual process of building up the transport solution in a continuous interaction between shippers and transport service providers. Research has focused on the shipper perspective on inter-modal transport, showing that switching to an intermodal transport is not simply a mode choice issue, but involves a transition process that takes time, demands resources, cooperation/coordination between multiple parties, may require changes in the supply chain beyond the transport link, involves multiple actors, and involves an industry that is itself in a process of change.
基金Under the auspices of Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA19040500)。
文摘To investigate the spatial synergy between agricultural development level and transport superiority degree in grain-producing areas of the central Jilin Province and the driving mechanism between them,22 counties in the central Jilin Province were used as the research units to calculate agricultural development level and transport superiority degree using the entropy weighting method,weighted travel time and raster cost distance.The spatial econometric model was used to analyze the mechanism of the mutual influence between the two.The main conclusions are as follows.1)Agricultural development level around Changchun,the provincial capital city,and in the areas of Changchun-Jilin and Changchun-Gongzhuling is high,whereas the development level of the counties in the southwest is low.2)Transport superiority degree of each county has improved,the overall connectivity of the road networks has been optimized,and the level of transportation accessibility has shown the development trend of‘centralization’,exhibiting the characteristics of proximity diffusion.3)Locally,there is spatial heterogeneity in the mutual driving effects of the two,with six main patterns.4)The theoretical conditions of von Thunen’s agricultural location have changed under the conditions of market economy due to the improvement of the transport networks,the new model of agricultural development,and the changes of the market system.
基金the Key Research Project of Heilongjiang Province's Economic and Social Development in 2019"Research on the Countermeasures for Cultivating Modern Agricultural Talents in Heilongjiang Province in the Context of Rural Revitalization"(19045)。
文摘The rise of the edible fungus industry has not only greatly increased the income of Chinese farmers,but also promoted the economic,social and ecological development of rural areas.Through a survey of the edible fungus industry in Heilongjiang Province,it found problems such as insufficient standardized production bases,insufficient coverage of"Internet+edible fungi",weak industrial clusters,conservative management ideas,and lack of professional talents.The development potential of edible fungi was analyzed and reasonable recommendations were put forward to promote the healthy,efficient and sustainable development of the edible fungus industry in Heilongjiang Province.
文摘The characteristics of highway transport and the application of information technology in highway transport service are combined; the information flows' promotion and substitution on highway transport are analyzed; and the highway transport development strategy based on information flow impact is proposed.