Pub Date : 2025-02-04DOI: 10.1016/j.jue.2025.103749
Elio Bolliger , Adrian Bruhin , Andreas Fuster , Maja Ganarin
This paper studies how the introduction of macroprudential policies in the Swiss residential mortgage market affected the propensity of households to become homeowners. We exploit a unique administrative data set of individual tax records containing detailed financial and socio-demographic information. We show that the mean share of renter households transitioning into homeownership decreased from 3.4% per year in the five years prior to the introduction of macroprudential policies to 3.0% per year in the five years afterward. This decrease is more pronounced for young and middle-aged households with relatively low income and wealth, suggesting that it is at least partly due to a tightening in borrowing constraints. Moreover, intergenerational transfers in the form of predeath bequests have become more important for homebuying both at the extensive and intensive margin.
{"title":"The effect of macroprudential policies on homeownership: Evidence from Switzerland","authors":"Elio Bolliger , Adrian Bruhin , Andreas Fuster , Maja Ganarin","doi":"10.1016/j.jue.2025.103749","DOIUrl":"10.1016/j.jue.2025.103749","url":null,"abstract":"<div><div>This paper studies how the introduction of macroprudential policies in the Swiss residential mortgage market affected the propensity of households to become homeowners. We exploit a unique administrative data set of individual tax records containing detailed financial and socio-demographic information. We show that the mean share of renter households transitioning into homeownership decreased from 3.4% per year in the five years prior to the introduction of macroprudential policies to 3.0% per year in the five years afterward. This decrease is more pronounced for young and middle-aged households with relatively low income and wealth, suggesting that it is at least partly due to a tightening in borrowing constraints. Moreover, intergenerational transfers in the form of predeath bequests have become more important for homebuying both at the extensive and intensive margin.</div></div>","PeriodicalId":48340,"journal":{"name":"Journal of Urban Economics","volume":"146 ","pages":"Article 103749"},"PeriodicalIF":5.7,"publicationDate":"2025-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143161494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-30DOI: 10.1016/j.jue.2024.103735
Florin Cucu
This article studies the effects of a major transport infrastructure project, the construction of the U.S. Interstate Highway System (IHS), on the location choices and welfare of high-skill and low-skill workers. In its first part, the article provides reduced-form evidence that the IHS altered the skill composition of metropolitan areas. Event study and instrumental variable regressions show that better-connected cities experienced higher growth in their adult population and share of college-educated residents. Additional results highlight the role played by lower travel times, inter-state migration, and agglomeration economies. The second part of the article rationalizes these patterns using a quantitative spatial model with costly trade, heterogeneous migration costs, and agglomeration economies. Counterfactual experiments show that increasing travel times to their pre-IHS values would lower the expected utility of high-skill workers by an average of 6.1% and that of low-skill workers by 6.4%. These effects exhibit significant variation across cities and, within cities, across skill groups. The findings in this article highlight how transport infrastructure shapes the distribution of skills and the spatial patterns of welfare inequality.
{"title":"Roads, internal migration and the spatial sorting of U.S. high-skill workers","authors":"Florin Cucu","doi":"10.1016/j.jue.2024.103735","DOIUrl":"10.1016/j.jue.2024.103735","url":null,"abstract":"<div><div>This article studies the effects of a major transport infrastructure project, the construction of the U.S. Interstate Highway System (IHS), on the location choices and welfare of high-skill and low-skill workers. In its first part, the article provides reduced-form evidence that the IHS altered the skill composition of metropolitan areas. Event study and instrumental variable regressions show that better-connected cities experienced higher growth in their adult population and share of college-educated residents. Additional results highlight the role played by lower travel times, inter-state migration, and agglomeration economies. The second part of the article rationalizes these patterns using a quantitative spatial model with costly trade, heterogeneous migration costs, and agglomeration economies. Counterfactual experiments show that increasing travel times to their pre-IHS values would lower the expected utility of high-skill workers by an average of 6.1% and that of low-skill workers by 6.4%. These effects exhibit significant variation across cities and, within cities, across skill groups. The findings in this article highlight how transport infrastructure shapes the distribution of skills and the spatial patterns of welfare inequality.</div></div>","PeriodicalId":48340,"journal":{"name":"Journal of Urban Economics","volume":"146 ","pages":"Article 103735"},"PeriodicalIF":5.7,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143161878","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-27DOI: 10.1016/j.jue.2025.103736
Xiaomeng Cui , Wangyang Lai , Tao Lin
Water is unevenly distributed across regions, yet the effectiveness of long-distance water transfer in addressing this issue remains understudied. This paper employs a difference-in-difference design to examine the impact of the world’s largest water transfer project on water resources, rural development, and urban growth. We find that the project enhances water supply and agricultural production in water-receiving areas, while it leads to agricultural declines in water-sourcing areas. Such diverging patterns contribute to various consequences on labor market and rural welfare, thereby generating further differential impacts on nearby urban growth. The water-receiving areas witness urban expansion and economic activities thrive in the rural-urban fringe, but in the water-sourcing areas, economic activities decline outside the core urban areas. Further analysis reveals significant heterogeneity between the two water-transfer routes, distinguished by their engineering designs.
{"title":"Long-distance water infrastructure, rural development and urban growth: Evidence from China","authors":"Xiaomeng Cui , Wangyang Lai , Tao Lin","doi":"10.1016/j.jue.2025.103736","DOIUrl":"10.1016/j.jue.2025.103736","url":null,"abstract":"<div><div>Water is unevenly distributed across regions, yet the effectiveness of long-distance water transfer in addressing this issue remains understudied. This paper employs a difference-in-difference design to examine the impact of the world’s largest water transfer project on water resources, rural development, and urban growth. We find that the project enhances water supply and agricultural production in water-receiving areas, while it leads to agricultural declines in water-sourcing areas. Such diverging patterns contribute to various consequences on labor market and rural welfare, thereby generating further differential impacts on nearby urban growth. The water-receiving areas witness urban expansion and economic activities thrive in the rural-urban fringe, but in the water-sourcing areas, economic activities decline outside the core urban areas. Further analysis reveals significant heterogeneity between the two water-transfer routes, distinguished by their engineering designs.</div></div>","PeriodicalId":48340,"journal":{"name":"Journal of Urban Economics","volume":"146 ","pages":"Article 103736"},"PeriodicalIF":5.7,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143161877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-24DOI: 10.1016/j.jue.2024.103734
Mary Kate Batistich, William N. Evans, David C. Phillips
One quarter of people in jail have a serious mental illness (SMI); we study a county in a multi-state area that screens all inmates to identify those with one. Immediately after jail exit, county staff attempt to contact and connect these individuals to a mental healthcare provider, making successful connections in one in four cases. As outreach began on a specific date and residents of neighboring counties are ineligible for outreach, we compare residents and non-residents exiting the same jail over time in a difference-in-differences design. When the program begins, 180-day recidivism rates fall by 12 percentage points more for eligible residents than for would-be-eligible non-residents. Measured effects at one year are consistent with a persistent impact over time. We also find suggestive evidence that recidivism effects are larger for people without a history of mental healthcare.
{"title":"Reducing the burden of mental illness on the criminal justice system: Evidence from light-touch outreach","authors":"Mary Kate Batistich, William N. Evans, David C. Phillips","doi":"10.1016/j.jue.2024.103734","DOIUrl":"10.1016/j.jue.2024.103734","url":null,"abstract":"<div><div>One quarter of people in jail have a serious mental illness (SMI); we study a county in a multi-state area that screens all inmates to identify those with one. Immediately after jail exit, county staff attempt to contact and connect these individuals to a mental healthcare provider, making successful connections in one in four cases. As outreach began on a specific date and residents of neighboring counties are ineligible for outreach, we compare residents and non-residents exiting the same jail over time in a difference-in-differences design. When the program begins, 180-day recidivism rates fall by 12 percentage points more for eligible residents than for would-be-eligible non-residents. Measured effects at one year are consistent with a persistent impact over time. We also find suggestive evidence that recidivism effects are larger for people without a history of mental healthcare.</div></div>","PeriodicalId":48340,"journal":{"name":"Journal of Urban Economics","volume":"146 ","pages":"Article 103734"},"PeriodicalIF":5.7,"publicationDate":"2025-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143161876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-21DOI: 10.1016/j.jue.2025.103737
Panka Bencsik , Lester Lusher , Rebecca L.C. Taylor
Time scarcity is one of the strongest correlates of fast food consumption. To estimate the causal effect of time lost on food choice, we match daily store-specific foot traffic data traced via smartphones to plausibly exogenous shocks in highway traffic congestion in Los Angeles County. We find that on days when highways are more congested, individuals are more likely to frequent fast food restaurants and less likely to grocery shop. In our main model, a one standard deviation increase in traffic delay leads to a 1% increase in fast food visits, equivalent to 1.2 million more fast food visits in Los Angeles County per year. The effects are particularly pronounced for afternoon rush hour traffic. Our results imply a net reduction in healthy food store choice due to time lost.
{"title":"Slow traffic, fast food: The effects of time lost on food store choice","authors":"Panka Bencsik , Lester Lusher , Rebecca L.C. Taylor","doi":"10.1016/j.jue.2025.103737","DOIUrl":"10.1016/j.jue.2025.103737","url":null,"abstract":"<div><div>Time scarcity is one of the strongest correlates of fast food consumption. To estimate the causal effect of time lost on food choice, we match daily store-specific foot traffic data traced via smartphones to plausibly exogenous shocks in highway traffic congestion in Los Angeles County. We find that on days when highways are more congested, individuals are more likely to frequent fast food restaurants and less likely to grocery shop. In our main model, a one standard deviation increase in traffic delay leads to a 1% increase in fast food visits, equivalent to 1.2 million more fast food visits in Los Angeles County per year. The effects are particularly pronounced for afternoon rush hour traffic. Our results imply a net reduction in healthy food store choice due to time lost.</div></div>","PeriodicalId":48340,"journal":{"name":"Journal of Urban Economics","volume":"146 ","pages":"Article 103737"},"PeriodicalIF":5.7,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143161493","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-18DOI: 10.1016/j.jue.2025.103738
Hyejin Kim , Jongkwan Lee , Giovanni Peri
In this study, we evaluate the economic effects of a significant increase in low-skilled immigration in Korean Municipalities. Using a change in immigration policy in 2004 and the pre-existing immigrant networks we estimate the effects of low-skilled immigration on local wages, net native migration, and housing prices. We interpret the findings using a canonical representative agent spatial equilibrium model as in Glaeser and Gottlieb (2009) to infer the equilibrium effects of immigration on local productivity and amenities. An increase of immigrants equal to 1 percent of the local population generated a 1% increase in local productivity and a 1.6% decrease in local amenities. We also find a net migration response of zero among natives deriving from an inflow of those who moved for work-related and an outflow of those who moved for amenity-related reasons. Finally, we find a direct negative effect of the immigration shock on measures of local amenities.
{"title":"The effect of low-skilled immigration on local productivity and amenities: Learning from the South Korean experience","authors":"Hyejin Kim , Jongkwan Lee , Giovanni Peri","doi":"10.1016/j.jue.2025.103738","DOIUrl":"10.1016/j.jue.2025.103738","url":null,"abstract":"<div><div>In this study, we evaluate the economic effects of a significant increase in low-skilled immigration in Korean Municipalities. Using a change in immigration policy in 2004 and the pre-existing immigrant networks we estimate the effects of low-skilled immigration on local wages, net native migration, and housing prices. We interpret the findings using a canonical representative agent spatial equilibrium model as in Glaeser and Gottlieb (2009) to infer the equilibrium effects of immigration on local productivity and amenities. An increase of immigrants equal to 1 percent of the local population generated a 1% increase in local productivity and a 1.6% decrease in local amenities. We also find a net migration response of zero among natives deriving from an inflow of those who moved for work-related and an outflow of those who moved for amenity-related reasons. Finally, we find a direct negative effect of the immigration shock on measures of local amenities.</div></div>","PeriodicalId":48340,"journal":{"name":"Journal of Urban Economics","volume":"146 ","pages":"Article 103738"},"PeriodicalIF":5.7,"publicationDate":"2025-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143161435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-01DOI: 10.1016/j.jue.2024.103725
Claes Bäckman , Chandler Lutz
We study how mortgage innovation can cause a housing boom even within a robust regulatory framework and strictly enforced recourse borrowing. Specifically, we find that the 2003 introduction of interest-only (IO) mortgages in Denmark ignited a housing boom that increased house prices 36 percent. In line with IO loans lowering debt-service payments and relaxing payment-to-income constraints, results show higher IO loan uptake and house price growth in areas with greater ex-ante benefits of such mortgages. Overall, our results are relevant for the many countries where IO loans play a sizable role in mortgage finance.
{"title":"Mortgage innovation and house price booms","authors":"Claes Bäckman , Chandler Lutz","doi":"10.1016/j.jue.2024.103725","DOIUrl":"10.1016/j.jue.2024.103725","url":null,"abstract":"<div><div>We study how mortgage innovation can cause a housing boom even within a robust regulatory framework and strictly enforced recourse borrowing. Specifically, we find that the 2003 introduction of interest-only (IO) mortgages in Denmark ignited a housing boom that increased house prices 36 percent. In line with IO loans lowering debt-service payments and relaxing payment-to-income constraints, results show higher IO loan uptake and house price growth in areas with greater ex-ante benefits of such mortgages. Overall, our results are relevant for the many countries where IO loans play a sizable role in mortgage finance.</div></div>","PeriodicalId":48340,"journal":{"name":"Journal of Urban Economics","volume":"145 ","pages":"Article 103725"},"PeriodicalIF":5.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143096323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-01DOI: 10.1016/j.jue.2024.103733
Guglielmo Barone , Guido de Blasio , Elena Gentili
This paper documents the higher growth experienced by politically connected municipalities in Italy between the end of World War II and the fall of the Berlin Wall. It leverages the peculiarities of the institutional setting and compares population growth in connected and unconnected municipalities with similar characteristics at the beginning of the period. Our results indicate a population premium of 7.4% over 40 years. Connected municipalities benefited from the location of state-owned enterprises, more infrastructures and higher public spending. Political connections favored industrialization, higher employment and wages, but crowded out private entrepreneurship. Local communities repaid these benefits through voting. There is no evidence of higher agglomeration economies in politically connected cities, suggesting that political connections have not been output-enhancing from a nationwide perspective. The difference in population growth rates fades away after the end of the connections.
{"title":"Politically connected cities: Italy 1951–1991","authors":"Guglielmo Barone , Guido de Blasio , Elena Gentili","doi":"10.1016/j.jue.2024.103733","DOIUrl":"10.1016/j.jue.2024.103733","url":null,"abstract":"<div><div>This paper documents the higher growth experienced by politically connected municipalities in Italy between the end of World War II and the fall of the Berlin Wall. It leverages the peculiarities of the institutional setting and compares population growth in connected and unconnected municipalities with similar characteristics at the beginning of the period. Our results indicate a population premium of 7.4% over 40 years. Connected municipalities benefited from the location of state-owned enterprises, more infrastructures and higher public spending. Political connections favored industrialization, higher employment and wages, but crowded out private entrepreneurship. Local communities repaid these benefits through voting. There is no evidence of higher agglomeration economies in politically connected cities, suggesting that political connections have not been output-enhancing from a nationwide perspective. The difference in population growth rates fades away after the end of the connections.</div></div>","PeriodicalId":48340,"journal":{"name":"Journal of Urban Economics","volume":"145 ","pages":"Article 103733"},"PeriodicalIF":5.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143096320","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-01DOI: 10.1016/j.jue.2024.103731
Ziyang Chen , Ting Chen , Yatang Lin , Jin Wang
This article examines the determinants and economic efficiency of state-led urbanization, increasingly the mantra of developing countries, focusing on China’s skyscraper development as a prominent example. Employing a political economy lens, we find that local governments subsidized skyscraper development through discounted land prices to encourage the development of new urban agglomerations, particularly in cities where local leaders are motivated by stronger career incentives and during the central government’s monetary easing policy period. But 5 to 10 years after completion, subsidized skyscrapers yield few spatial spillovers in land price premium, new business formation, or endogenous urban amenities, compared to unsubsidized ones. The lack of spillovers is caused by poor location, less reliable developers, and inadequate infrastructure. One important policy implication is that without careful consideration of local factors and related externalities, state interventions in urban development may fail to realize the fruits of public investment.
{"title":"Building tall, falling short: An empirical assessment of Chinese skyscrapers","authors":"Ziyang Chen , Ting Chen , Yatang Lin , Jin Wang","doi":"10.1016/j.jue.2024.103731","DOIUrl":"10.1016/j.jue.2024.103731","url":null,"abstract":"<div><div>This article examines the determinants and economic efficiency of state-led urbanization, increasingly the mantra of developing countries, focusing on China’s skyscraper development as a prominent example. Employing a political economy lens, we find that local governments subsidized skyscraper development through discounted land prices to encourage the development of new urban agglomerations, particularly in cities where local leaders are motivated by stronger career incentives and during the central government’s monetary easing policy period. But 5 to 10 years after completion, subsidized skyscrapers yield few spatial spillovers in land price premium, new business formation, or endogenous urban amenities, compared to unsubsidized ones. The lack of spillovers is caused by poor location, less reliable developers, and inadequate infrastructure. One important policy implication is that without careful consideration of local factors and related externalities, state interventions in urban development may fail to realize the fruits of public investment.</div></div>","PeriodicalId":48340,"journal":{"name":"Journal of Urban Economics","volume":"145 ","pages":"Article 103731"},"PeriodicalIF":5.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143096325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-01DOI: 10.1016/j.jue.2024.103730
Richard Bluhm , Axel Dreher , Andreas Fuchs , Bradley C. Parks , Austin M. Strange , Michael J. Tierney
This paper studies the causal effect of transport infrastructure on the spatial distribution of economic activity within subnational regions across a large number of developing countries. To do so, we introduce a new global dataset of geolocated Chinese grant- and loan-financed development projects from 2000 to 2014 and combine it with measures of spatial concentration based on remotely sensed data. We find that Chinese-financed transportation projects decentralize economic activity within regions, as measured by a spatial Gini coefficient, by 2.2 percentage points. The treatment effects are particularly strong in regions that are less developed, more urbanized, and located closer to cities.
{"title":"Connective financing: Chinese infrastructure projects and the diffusion of economic activity in developing countries","authors":"Richard Bluhm , Axel Dreher , Andreas Fuchs , Bradley C. Parks , Austin M. Strange , Michael J. Tierney","doi":"10.1016/j.jue.2024.103730","DOIUrl":"10.1016/j.jue.2024.103730","url":null,"abstract":"<div><div>This paper studies the causal effect of transport infrastructure on the spatial distribution of economic activity within subnational regions across a large number of developing countries. To do so, we introduce a new global dataset of geolocated Chinese grant- and loan-financed development projects from 2000 to 2014 and combine it with measures of spatial concentration based on remotely sensed data. We find that Chinese-financed transportation projects decentralize economic activity within regions, as measured by a spatial Gini coefficient, by 2.2 percentage points. The treatment effects are particularly strong in regions that are less developed, more urbanized, and located closer to cities.</div></div>","PeriodicalId":48340,"journal":{"name":"Journal of Urban Economics","volume":"145 ","pages":"Article 103730"},"PeriodicalIF":5.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143096322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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