Pub Date : 2022-07-26DOI: 10.1080/17421772.2022.2096917
M. Rizzati, G. Standardi, G. Guastella, R. Parrado, F. Bosello, S. Pareglio
ABSTRACT We present a tractable methodology to estimate climate change costs at a 1 × 1 km grid resolution. Climate change costs are obtained as projected gross domestic product (GDP) changes, under different global shared socio-economic pathway–representative concentration pathway (SSP-RCP) scenarios, from a regional (multiple European NUTS levels) version of the Intertemporal Computable Equilibrium System (ICES) model. Local costs are obtained by downscaling projected GDP according to urbanized area estimated by a grid-level model that accounts for fixed effects, such as population and location, and spatially clustered random effects at multiple hierarchical administrative levels. We produce a grid-level dataset of climate change economic impacts under different scenarios that can be used to compare the cost – in terms of GDP loss – of no adaptation and the benefits of investing in local adaptation.
{"title":"The local costs of global climate change: spatial GDP downscaling under different climate scenarios","authors":"M. Rizzati, G. Standardi, G. Guastella, R. Parrado, F. Bosello, S. Pareglio","doi":"10.1080/17421772.2022.2096917","DOIUrl":"https://doi.org/10.1080/17421772.2022.2096917","url":null,"abstract":"ABSTRACT We present a tractable methodology to estimate climate change costs at a 1 × 1 km grid resolution. Climate change costs are obtained as projected gross domestic product (GDP) changes, under different global shared socio-economic pathway–representative concentration pathway (SSP-RCP) scenarios, from a regional (multiple European NUTS levels) version of the Intertemporal Computable Equilibrium System (ICES) model. Local costs are obtained by downscaling projected GDP according to urbanized area estimated by a grid-level model that accounts for fixed effects, such as population and location, and spatially clustered random effects at multiple hierarchical administrative levels. We produce a grid-level dataset of climate change economic impacts under different scenarios that can be used to compare the cost – in terms of GDP loss – of no adaptation and the benefits of investing in local adaptation.","PeriodicalId":47008,"journal":{"name":"Spatial Economic Analysis","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2022-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47573257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-26DOI: 10.1080/17421772.2022.2097729
Federica Galli
ABSTRACT Spatial dependence in stochastic frontier models is usually handled by modelling the frontier function or the inefficiency error term through the introduction of some spatial components. The model proposed in this paper (SDF-CSD) combines the two different modelling approaches, obtaining a full comprehensive specification that introduces four different sources of spatial cross-sectional dependence. The most appealing feature of the model is that it allows capturing global and local spatial spillover effects while controlling for spatial correlation related to firms’ efficiency and to unobserved but spatially correlated variables. Moreover, it can be estimated using maximum likelihood techniques. Finally, some Monte Carlo simulations were run to test the final sample properties of the new spatial estimator and an application to the Italian agricultural sector is provided.
{"title":"A spatial stochastic frontier model including both frontier and error-based spatial cross-sectional dependence","authors":"Federica Galli","doi":"10.1080/17421772.2022.2097729","DOIUrl":"https://doi.org/10.1080/17421772.2022.2097729","url":null,"abstract":"ABSTRACT Spatial dependence in stochastic frontier models is usually handled by modelling the frontier function or the inefficiency error term through the introduction of some spatial components. The model proposed in this paper (SDF-CSD) combines the two different modelling approaches, obtaining a full comprehensive specification that introduces four different sources of spatial cross-sectional dependence. The most appealing feature of the model is that it allows capturing global and local spatial spillover effects while controlling for spatial correlation related to firms’ efficiency and to unobserved but spatially correlated variables. Moreover, it can be estimated using maximum likelihood techniques. Finally, some Monte Carlo simulations were run to test the final sample properties of the new spatial estimator and an application to the Italian agricultural sector is provided.","PeriodicalId":47008,"journal":{"name":"Spatial Economic Analysis","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2022-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46419849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-21DOI: 10.1080/17421772.2022.2095005
Margherita Gerolimetto, S. Magrini
ABSTRACT It is quite common in cross-sectional convergence analyses that data exhibit spatial dependence. Within the literature adopting the distribution dynamics approach, authors typically opt for spatial prefiltering. We follow an alternative route and propose a procedure based on an estimate of the mean function of a conditional density for which we develop a two-stage non-parametric estimator that allows for spatial dependence estimated via a spline estimator of the spatial correlation function. The finite sample performance of this estimator is assessed via Monte Carlo simulations. We apply the procedure that incorporates the proposed spatial non-parametric estimator to data on per capita personal income in US states and metropolitan statistical areas.
{"title":"Distribution dynamics: a spatial perspective","authors":"Margherita Gerolimetto, S. Magrini","doi":"10.1080/17421772.2022.2095005","DOIUrl":"https://doi.org/10.1080/17421772.2022.2095005","url":null,"abstract":"ABSTRACT It is quite common in cross-sectional convergence analyses that data exhibit spatial dependence. Within the literature adopting the distribution dynamics approach, authors typically opt for spatial prefiltering. We follow an alternative route and propose a procedure based on an estimate of the mean function of a conditional density for which we develop a two-stage non-parametric estimator that allows for spatial dependence estimated via a spline estimator of the spatial correlation function. The finite sample performance of this estimator is assessed via Monte Carlo simulations. We apply the procedure that incorporates the proposed spatial non-parametric estimator to data on per capita personal income in US states and metropolitan statistical areas.","PeriodicalId":47008,"journal":{"name":"Spatial Economic Analysis","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2022-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41801340","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-03DOI: 10.1080/17421772.2022.2088660
P. Elhorst, M. Abreu, P. Amaral, A. Bhattacharjee, Steven Bond‐Smith, C. Chasco, L. Corrado, J. Ditzen, D. Felsenstein, F. Fuerst, P. McCann, V. Monastiriotis, F. Quatraro, Umed Temursho, D. Tsiotas, Jihai Yu
ABSTRACT This editorial summarizes the papers published in issue 17(3) (2022). The first paper analyses the impact of knowledge spillovers on patent applications using a Tobit model. The second paper sets out an economic-theoretical model of industrial specialization patterns across cities and their impact on the spatial agglomeration of skilled workers and long-term productivity growth. The third paper analyses the price and average cost functions of a competitive industry in which firms face diseconomies of scale but enjoy economies of scale when they agglomerate. The fourth paper shows that productivity spillover effects and their endogeneity are key to understanding the productivity-compensation gap. The fifth paper studies geographical and sectoral specialization versus concentration of global supply chains. The sixth paper combines spatial autoregressive (SAR) and geographically weighted regression (GWR) models to test whether urban residents have reacted to the Covid-19 pandemic by moving out of US metropolitan centres into the suburbs. The seventh paper investigates the impact of natural disasters caused by climate change on forced outmigration flows in South and South-East Asian countries.
{"title":"Raising the bar (21)","authors":"P. Elhorst, M. Abreu, P. Amaral, A. Bhattacharjee, Steven Bond‐Smith, C. Chasco, L. Corrado, J. Ditzen, D. Felsenstein, F. Fuerst, P. McCann, V. Monastiriotis, F. Quatraro, Umed Temursho, D. Tsiotas, Jihai Yu","doi":"10.1080/17421772.2022.2088660","DOIUrl":"https://doi.org/10.1080/17421772.2022.2088660","url":null,"abstract":"ABSTRACT This editorial summarizes the papers published in issue 17(3) (2022). The first paper analyses the impact of knowledge spillovers on patent applications using a Tobit model. The second paper sets out an economic-theoretical model of industrial specialization patterns across cities and their impact on the spatial agglomeration of skilled workers and long-term productivity growth. The third paper analyses the price and average cost functions of a competitive industry in which firms face diseconomies of scale but enjoy economies of scale when they agglomerate. The fourth paper shows that productivity spillover effects and their endogeneity are key to understanding the productivity-compensation gap. The fifth paper studies geographical and sectoral specialization versus concentration of global supply chains. The sixth paper combines spatial autoregressive (SAR) and geographically weighted regression (GWR) models to test whether urban residents have reacted to the Covid-19 pandemic by moving out of US metropolitan centres into the suburbs. The seventh paper investigates the impact of natural disasters caused by climate change on forced outmigration flows in South and South-East Asian countries.","PeriodicalId":47008,"journal":{"name":"Spatial Economic Analysis","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2022-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42831859","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-06-20DOI: 10.1080/17421772.2022.2081714
E. Sanguinet, C. Azzoni, Miguel Atienza Ubeda, A. Alvim
ABSTRACT Sophisticated spatial labour markets can promote better opportunities for functional upgrading in value-added trade. This paper estimates the skill-based functional specialization in Brazilian labour factor content in trade in value-added (LTiVA), considering different geographical scales. We combined an interregional input–output model for Brazilian states with occupational data to identify the skill intensity embedded in LTiVA based on the hypothetical extraction method (HEM) technique. Our findings show that the largest Southeastern economic area specializes in highly sophisticated functions, while the rest of the country embodies low skills in value-added trade for domestic and global trade levels. Furthermore, the results reveal a central role for the São Paulo state governing the subnational value chains and reinforcing the international uneven spatial functional division pattern at the subnational level.
{"title":"Skill-based functional specialization in trade: an input–output analysis of multiscalar value chains in Brazil","authors":"E. Sanguinet, C. Azzoni, Miguel Atienza Ubeda, A. Alvim","doi":"10.1080/17421772.2022.2081714","DOIUrl":"https://doi.org/10.1080/17421772.2022.2081714","url":null,"abstract":"ABSTRACT\u0000 Sophisticated spatial labour markets can promote better opportunities for functional upgrading in value-added trade. This paper estimates the skill-based functional specialization in Brazilian labour factor content in trade in value-added (LTiVA), considering different geographical scales. We combined an interregional input–output model for Brazilian states with occupational data to identify the skill intensity embedded in LTiVA based on the hypothetical extraction method (HEM) technique. Our findings show that the largest Southeastern economic area specializes in highly sophisticated functions, while the rest of the country embodies low skills in value-added trade for domestic and global trade levels. Furthermore, the results reveal a central role for the São Paulo state governing the subnational value chains and reinforcing the international uneven spatial functional division pattern at the subnational level.","PeriodicalId":47008,"journal":{"name":"Spatial Economic Analysis","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2022-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49591050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-06-06DOI: 10.1080/17421772.2022.2078872
Zemin Hou, S. Colombo
ABSTRACT We analyse the impact of online retailing on transportation gas emissions in a spatial duopoly with upstream suppliers. We consider: (1) pure offline competition with two physical retailers; and (2) online/offline competition, where an online retailer competes against an offline retailer. When the upstream suppliers are located in the city centre, transportation gas emissions are lower under online/offline competition. However, when the upstream suppliers are at the endpoints, online retailing might increase transportation gas emissions. This happens when: (1) in the online/offline competition case, the physical retailer does not locate at the endpoint; (2) the transportation costs of the suppliers’ commercial trucks are sufficiently larger than those of the consumers’ private cars; and (3) the competitiveness of the offline retailer is high enough.
{"title":"Transportation gas emissions with online retailing: a spatial model","authors":"Zemin Hou, S. Colombo","doi":"10.1080/17421772.2022.2078872","DOIUrl":"https://doi.org/10.1080/17421772.2022.2078872","url":null,"abstract":"ABSTRACT We analyse the impact of online retailing on transportation gas emissions in a spatial duopoly with upstream suppliers. We consider: (1) pure offline competition with two physical retailers; and (2) online/offline competition, where an online retailer competes against an offline retailer. When the upstream suppliers are located in the city centre, transportation gas emissions are lower under online/offline competition. However, when the upstream suppliers are at the endpoints, online retailing might increase transportation gas emissions. This happens when: (1) in the online/offline competition case, the physical retailer does not locate at the endpoint; (2) the transportation costs of the suppliers’ commercial trucks are sufficiently larger than those of the consumers’ private cars; and (3) the competitiveness of the offline retailer is high enough.","PeriodicalId":47008,"journal":{"name":"Spatial Economic Analysis","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2022-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44197034","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-06-01DOI: 10.1080/17421772.2022.2070656
Thibault Laurent, Paula Margaretic, C. Thomas-Agnan
ABSTRACT We measure to what extent neighbouring countries affect the amount of remittances between a source and a recipient country, controlling for the commonly used macro determinants of remittances. We provide novel evidence on the importance of neighbouring countries, with the parameter estimates capturing origin and destination spatial dependence being positive and significant. Disregarding the role of neighbouring countries leads to biased estimates and misprediction. Indeed, when we correctly account for the role of neighbouring countries, prediction errors decrease by 44% when we express bilateral remittances in nominal terms and by 31% when remittances are in logarithm. Next, we present evidence supporting the altruism, the investment and the financial friction motives to remit, with the altruism motive being the one that contributes the most to explain expected remittances. As an application of our model, we show that, following the Covid-19 shock, remittances are expected to decrease less in countries with smaller income per capita. This is good news for low- to middle-income countries.
{"title":"Neighbouring countries and bilateral remittances: a global study","authors":"Thibault Laurent, Paula Margaretic, C. Thomas-Agnan","doi":"10.1080/17421772.2022.2070656","DOIUrl":"https://doi.org/10.1080/17421772.2022.2070656","url":null,"abstract":"ABSTRACT We measure to what extent neighbouring countries affect the amount of remittances between a source and a recipient country, controlling for the commonly used macro determinants of remittances. We provide novel evidence on the importance of neighbouring countries, with the parameter estimates capturing origin and destination spatial dependence being positive and significant. Disregarding the role of neighbouring countries leads to biased estimates and misprediction. Indeed, when we correctly account for the role of neighbouring countries, prediction errors decrease by 44% when we express bilateral remittances in nominal terms and by 31% when remittances are in logarithm. Next, we present evidence supporting the altruism, the investment and the financial friction motives to remit, with the altruism motive being the one that contributes the most to explain expected remittances. As an application of our model, we show that, following the Covid-19 shock, remittances are expected to decrease less in countries with smaller income per capita. This is good news for low- to middle-income countries.","PeriodicalId":47008,"journal":{"name":"Spatial Economic Analysis","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43035615","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-25DOI: 10.1080/17421772.2022.2077417
Roberto Basile, N. Coniglio, Francesca Licar
ABSTRACT Diasporas play a fundamental role in explaining the location choice of new immigrants. We investigate the spatial dimension of diaspora externalities focusing on immigrants in Italian local labour market areas (LLMAs). We show that the net pull effect of diasporas spills over an estimated average distance of 82 km. We find evidence of negative spatial spillovers at greater geographical distances, suggesting a competition effect from neighbouring diasporas. Ethnic-specific labour markets and ethnic consumption externalities are important channels through which the distance–decay effects of diasporas take place. We also find that the spatial effects of diasporas are highly heterogeneous across gender and origin countries.
{"title":"Distance from diasporas and immigrants’ location choice: evidence from Italy","authors":"Roberto Basile, N. Coniglio, Francesca Licar","doi":"10.1080/17421772.2022.2077417","DOIUrl":"https://doi.org/10.1080/17421772.2022.2077417","url":null,"abstract":"ABSTRACT Diasporas play a fundamental role in explaining the location choice of new immigrants. We investigate the spatial dimension of diaspora externalities focusing on immigrants in Italian local labour market areas (LLMAs). We show that the net pull effect of diasporas spills over an estimated average distance of 82 km. We find evidence of negative spatial spillovers at greater geographical distances, suggesting a competition effect from neighbouring diasporas. Ethnic-specific labour markets and ethnic consumption externalities are important channels through which the distance–decay effects of diasporas take place. We also find that the spatial effects of diasporas are highly heterogeneous across gender and origin countries.","PeriodicalId":47008,"journal":{"name":"Spatial Economic Analysis","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2022-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43199978","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-19DOI: 10.1080/17421772.2022.2070657
Bartlomiej Rokicki, A. Cieślik
ABSTRACT This paper reconsiders the relationship between individual wages and regional market access. We focus on Poland – a country that has experienced profound changes in market accessibility over the last two decades, first as a consequence of European Union accession in 2004, and second as a result of the unprecedented development of the major road transport network. Using data over the period 2000–15 we find that the positive relationship between wages and regional market access disappears after 2004. At the same time, individual wages begin to be positively correlated with the market potential of Poland’s main trading partners.
{"title":"Rethinking regional wage determinants: regional market potential versus trade partners’ potential","authors":"Bartlomiej Rokicki, A. Cieślik","doi":"10.1080/17421772.2022.2070657","DOIUrl":"https://doi.org/10.1080/17421772.2022.2070657","url":null,"abstract":"ABSTRACT This paper reconsiders the relationship between individual wages and regional market access. We focus on Poland – a country that has experienced profound changes in market accessibility over the last two decades, first as a consequence of European Union accession in 2004, and second as a result of the unprecedented development of the major road transport network. Using data over the period 2000–15 we find that the positive relationship between wages and regional market access disappears after 2004. At the same time, individual wages begin to be positively correlated with the market potential of Poland’s main trading partners.","PeriodicalId":47008,"journal":{"name":"Spatial Economic Analysis","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2022-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49483295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-04-22DOI: 10.1080/17421772.2022.2061722
Gerben van Roekel, M. Smit
ABSTRACT Agglomeration externalities are generally credited as the prime cause of cluster formation. This theory is far from uncontroversial. We create an alternative perspective on clustering by integrating herd behaviour into the conceptualization of this process. An innovative agent-based model is used in which cluster formation is constructed from individual relocation decisions. It thus connects individual relocation decisions to macro-level emergent patterns and shows that imitation has the potential to severely exacerbate the effects of agglomeration economies on clustering on an urban scale. The outcomes of this model challenge the dominant neoclassical view on clustering. An alternative hypothesis is postulated in which the interaction between herd behaviour and agglomeration externalities is proposed as an explanation for cluster formation.
{"title":"Herd behaviour and the emergence of clusters","authors":"Gerben van Roekel, M. Smit","doi":"10.1080/17421772.2022.2061722","DOIUrl":"https://doi.org/10.1080/17421772.2022.2061722","url":null,"abstract":"ABSTRACT Agglomeration externalities are generally credited as the prime cause of cluster formation. This theory is far from uncontroversial. We create an alternative perspective on clustering by integrating herd behaviour into the conceptualization of this process. An innovative agent-based model is used in which cluster formation is constructed from individual relocation decisions. It thus connects individual relocation decisions to macro-level emergent patterns and shows that imitation has the potential to severely exacerbate the effects of agglomeration economies on clustering on an urban scale. The outcomes of this model challenge the dominant neoclassical view on clustering. An alternative hypothesis is postulated in which the interaction between herd behaviour and agglomeration externalities is proposed as an explanation for cluster formation.","PeriodicalId":47008,"journal":{"name":"Spatial Economic Analysis","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2022-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46921952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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