Pub Date : 2025-04-04DOI: 10.1016/j.jmacro.2025.103676
Charles Grant
The Permanent Income Hypothesis (PIH) can be tested using the excess-sensitivity test, which investigates whether current consumption is affected by predictable changes in income. Several studies have shown that households are overly sensitive to changes in current income, especially if they have low assets. This study shows that university educated households behave according to PIH, but that less educated households are excessively sensitive to predictable changes in income. This result is consistent with the idea that university-educated households are more patient.
{"title":"Comparing the response of different education groups to predictable changes in income","authors":"Charles Grant","doi":"10.1016/j.jmacro.2025.103676","DOIUrl":"10.1016/j.jmacro.2025.103676","url":null,"abstract":"<div><div>The Permanent Income Hypothesis (PIH) can be tested using the excess-sensitivity test, which investigates whether current consumption is affected by predictable changes in income. Several studies have shown that households are overly sensitive to changes in current income, especially if they have low assets. This study shows that university educated households behave according to PIH, but that less educated households are excessively sensitive to predictable changes in income. This result is consistent with the idea that university-educated households are more patient.</div></div>","PeriodicalId":47863,"journal":{"name":"Journal of Macroeconomics","volume":"84 ","pages":"Article 103676"},"PeriodicalIF":1.3,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143792578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 : 2025-03-22DOI: 10.1016/j.jmacro.2025.103675
João Tovar Jalles , Carola Pessino
Widening income disparities, higher corruption and larger informality in many emerging market and developing economies (EMDE) including Latin America, all with pressing and mounting fiscal problems, have rekindled interest in the empirical analysis of the key factors determining the occurrence of fiscal consolidations. Using discrete choice models, this paper examines the drivers of fiscal consolidation episodes in a sample of 148 EMDE between 1980 and 2019 with a focus on Latin America. Inequality does not seem to drive consolidations in Latin America, while more informality (corruption) increases (decreases) the probability of their occurrence. In turn, when examining the drivers of successful consolidations, larger income inequality (informality) seems to act as a boost (hinderance) for successful consolidations. Results are robust to several sensitivity and robustness tests.
{"title":"Fiscal consolidations in developing countries with a Latin America focus: The role of inequality, informality and corruption","authors":"João Tovar Jalles , Carola Pessino","doi":"10.1016/j.jmacro.2025.103675","DOIUrl":"10.1016/j.jmacro.2025.103675","url":null,"abstract":"<div><div>Widening income disparities, higher corruption and larger informality in many emerging market and developing economies (EMDE) including Latin America, all with pressing and mounting fiscal problems, have rekindled interest in the empirical analysis of the key factors determining the occurrence of fiscal consolidations. Using discrete choice models, this paper examines the drivers of fiscal consolidation episodes in a sample of 148 EMDE between 1980 and 2019 with a focus on Latin America. Inequality does not seem to drive consolidations in Latin America, while more informality (corruption) increases (decreases) the probability of their occurrence. In turn, when examining the drivers of successful consolidations, larger income inequality (informality) seems to act as a boost (hinderance) for successful consolidations. Results are robust to several sensitivity and robustness tests.</div></div>","PeriodicalId":47863,"journal":{"name":"Journal of Macroeconomics","volume":"84 ","pages":"Article 103675"},"PeriodicalIF":1.3,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143899319","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 : 2025-03-06DOI: 10.1016/j.jmacro.2025.103674
Maximilien Coussin
Using a Factor-Augmented Vector Autoregressive (FAVAR) model and extensions, this paper investigates the impact of monetary policy on various credit aggregates in the United States over sixty years. The analysis reveals that monetary policy impacts different types of credit heterogeneously, with credit to the financial sector reacting particularly strongly. Bank-held credit exhibits notable sensitivity to monetary policy shocks. The effects of monetary policy are also conditional on the phases of the economic and financial cycles, showing a much stronger impact during periods of expansion. Additionally, a long-term strengthening of the transmission mechanisms suggests that substantial structural changes have occurred over the past six decades.
{"title":"The multifaceted effect of monetary policy on U.S. credit aggregates","authors":"Maximilien Coussin","doi":"10.1016/j.jmacro.2025.103674","DOIUrl":"10.1016/j.jmacro.2025.103674","url":null,"abstract":"<div><div>Using a Factor-Augmented Vector Autoregressive (FAVAR) model and extensions, this paper investigates the impact of monetary policy on various credit aggregates in the United States over sixty years. The analysis reveals that monetary policy impacts different types of credit heterogeneously, with credit to the financial sector reacting particularly strongly. Bank-held credit exhibits notable sensitivity to monetary policy shocks. The effects of monetary policy are also conditional on the phases of the economic and financial cycles, showing a much stronger impact during periods of expansion. Additionally, a long-term strengthening of the transmission mechanisms suggests that substantial structural changes have occurred over the past six decades.</div></div>","PeriodicalId":47863,"journal":{"name":"Journal of Macroeconomics","volume":"84 ","pages":"Article 103674"},"PeriodicalIF":1.3,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143631994","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 : 2025-03-05DOI: 10.1016/j.jmacro.2025.103672
Alex Carrasco , David Florián Hoyle
We examine the role of sterilized FX interventions as a monetary policy tool in response to external shocks for dollarized emerging market economies. Our model highlights an agency problem that limits banks’ ability to secure funds in both domestic and foreign currencies, with its intensity linked to currency mismatches in the banking sector. This leads to endogenous deviations from the standard UIP condition, resulting in a non-neutral FX intervention policy. Sterilized FX interventions stabilize financial conditions not only by stabilizing real exchange rates but also by acting as a balance sheet policy that directly influences credit supply. Our quantitative analysis shows that FX policy rules that counteract exchange rate deviations reduce volatility in interest rate spreads including UIP deviations, credit, investment, and output, leading to significant welfare improvements compared to a flexible exchange rate regime.
{"title":"External shocks and FX intervention policy in financially dollarized economies","authors":"Alex Carrasco , David Florián Hoyle","doi":"10.1016/j.jmacro.2025.103672","DOIUrl":"10.1016/j.jmacro.2025.103672","url":null,"abstract":"<div><div>We examine the role of sterilized FX interventions as a monetary policy tool in response to external shocks for dollarized emerging market economies. Our model highlights an agency problem that limits banks’ ability to secure funds in both domestic and foreign currencies, with its intensity linked to currency mismatches in the banking sector. This leads to endogenous deviations from the standard UIP condition, resulting in a non-neutral FX intervention policy. Sterilized FX interventions stabilize financial conditions not only by stabilizing real exchange rates but also by acting as a balance sheet policy that directly influences credit supply. Our quantitative analysis shows that FX policy rules that counteract exchange rate deviations reduce volatility in interest rate spreads including UIP deviations, credit, investment, and output, leading to significant welfare improvements compared to a flexible exchange rate regime.</div></div>","PeriodicalId":47863,"journal":{"name":"Journal of Macroeconomics","volume":"84 ","pages":"Article 103672"},"PeriodicalIF":1.3,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143594108","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 : 2025-03-01DOI: 10.1016/j.jmacro.2025.103673
Chia-Hui Lu
By introducing the development of automation into a labor search model with differently skilled workers, this paper finds that increased automation of production processes leads to job polarization. When there is an increase in the degree to which automation and middle-skilled labor can replace each other, firms producing final goods will use automation in place of human labor rather than the other way around. In economies where people can acquire skills and make endogenous occupational choices, government subsidies to cover the learning costs of high-skilled labor enhance output production and household welfare, but increase the degree of job polarization. Furthermore, we find that reducing job polarization is not necessarily beneficial for macroeconomic performance when the government subsidizes the cost of learning for household members to become middle-skilled workers.
{"title":"Automation and job polarization","authors":"Chia-Hui Lu","doi":"10.1016/j.jmacro.2025.103673","DOIUrl":"10.1016/j.jmacro.2025.103673","url":null,"abstract":"<div><div>By introducing the development of automation into a labor search model with differently skilled workers, this paper finds that increased automation of production processes leads to job polarization. When there is an increase in the degree to which automation and middle-skilled labor can replace each other, firms producing final goods will use automation in place of human labor rather than the other way around. In economies where people can acquire skills and make endogenous occupational choices, government subsidies to cover the learning costs of high-skilled labor enhance output production and household welfare, but increase the degree of job polarization. Furthermore, we find that reducing job polarization is not necessarily beneficial for macroeconomic performance when the government subsidizes the cost of learning for household members to become middle-skilled workers.</div></div>","PeriodicalId":47863,"journal":{"name":"Journal of Macroeconomics","volume":"84 ","pages":"Article 103673"},"PeriodicalIF":1.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143552926","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}
This paper examines the influence of third countries on the output synchronization between two trading partners. We first address this issue in a three-country Dynamic Stochastic General Equilibrium model, where trade in intermediate goods operates at the intensive and extensive margins. We find that adding a third trading partner strengthens the output co-movement between two countries through two channels: a trade channel, driven by a higher total number of varieties traded that makes production processes more homogeneous across countries, and a macroeconomic channel where the third country exerts a stabilizing effect on the intensive and extensive margins of production in the other two countries. Applying Jordà’s local projections to 34 countries from 1979Q2 to 2019Q4, we find that the inclusion of a third partner raises the output co-movement in 75% of cases on average, with a median rise of 54% on average compared to the two-country case. Our results are robust to (i) an alternative identification of productivity shocks and (ii) the inclusion of extensive trade margins as control variables. Those stylized facts of upward output synchronization resulting from the explicit inclusion of a third trading partner are consistent with our theoretical predictions.
{"title":"Bilateral output synchronization in a globalized world: A macroeconomic evaluation of the third-country effect","authors":"Jean-Sébastien Pentecôte , Jean-Christophe Poutineau , Tovonony Razafindrabe , Fabien Rondeau","doi":"10.1016/j.jmacro.2025.103665","DOIUrl":"10.1016/j.jmacro.2025.103665","url":null,"abstract":"<div><div>This paper examines the influence of third countries on the output synchronization between two trading partners. We first address this issue in a three-country Dynamic Stochastic General Equilibrium model, where trade in intermediate goods operates at the intensive and extensive margins. We find that adding a third trading partner strengthens the output co-movement between two countries through two channels: a trade channel, driven by a higher total number of varieties traded that makes production processes more homogeneous across countries, and a macroeconomic channel where the third country exerts a stabilizing effect on the intensive and extensive margins of production in the other two countries. Applying Jordà’s local projections to 34 countries from 1979Q2 to 2019Q4, we find that the inclusion of a third partner raises the output co-movement in 75% of cases on average, with a median rise of 54% on average compared to the two-country case. Our results are robust to (i) an alternative identification of productivity shocks and (ii) the inclusion of extensive trade margins as control variables. Those stylized facts of upward output synchronization resulting from the explicit inclusion of a third trading partner are consistent with our theoretical predictions.</div></div>","PeriodicalId":47863,"journal":{"name":"Journal of Macroeconomics","volume":"84 ","pages":"Article 103665"},"PeriodicalIF":1.3,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143474724","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 : 2025-02-10DOI: 10.1016/j.jmacro.2025.103664
Antonia López-Villavicencio, Jocelyne Zoumenou
We study the impact of fiscal rules on EU countries’ fiscal stability, particularly within the Stability and Growth Pact (SGP) framework. By rigorously addressing endogeneity concerns, we show that, among all the rules imposed by the SGP, compliance with budget balance rules (BBR) and to a lesser extent, deficit rules, are the only ones that contribute to fiscal stability. However, countries that comply with other targets – either individually, simultaneously, or by adopting a constitutional BBR – do not perform better than those that comply exclusively with the budget balance rule. Finally, our results suggest that strong fiscal rules are not necessary to achieve better fiscal discipline.
{"title":"Do commitment and enforcement of fiscal rules enhance fiscal stability? Evidence from European Union countries","authors":"Antonia López-Villavicencio, Jocelyne Zoumenou","doi":"10.1016/j.jmacro.2025.103664","DOIUrl":"10.1016/j.jmacro.2025.103664","url":null,"abstract":"<div><div>We study the impact of fiscal rules on EU countries’ fiscal stability, particularly within the Stability and Growth Pact (SGP) framework. By rigorously addressing endogeneity concerns, we show that, among all the rules imposed by the SGP, compliance with budget balance rules (BBR) and to a lesser extent, deficit rules, are the only ones that contribute to fiscal stability. However, countries that comply with other targets – either individually, simultaneously, or by adopting a constitutional BBR – do not perform better than those that comply exclusively with the budget balance rule. Finally, our results suggest that strong fiscal rules are not necessary to achieve better fiscal discipline.</div></div>","PeriodicalId":47863,"journal":{"name":"Journal of Macroeconomics","volume":"84 ","pages":"Article 103664"},"PeriodicalIF":1.3,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143386807","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 : 2025-01-18DOI: 10.1016/j.jmacro.2024.103660
Amaia Iza, Ibai Ostolozaga
The aim of this paper is to analyze the effect of relaxing borrowing constraints taking into account that firms may be facing either earnings-based or asset-based borrowing constraints on some aggregates such GDP per worker or TFP. We also analyze the impact on those aggregates of increasing the proportion of firms with earnings-based borrowing constraints. Using the World Bank Enterprise Survey, we show that the proportion of firms whose loans require collateral is lower in those countries whose bankruptcy laws facilitate reorganization. In addition, we show that there are no significant differences in the median/average contract-enforcement scores between countries where bankruptcy laws facilitate reorganization and countries where they do not, and that there is a significant negative link between the contract-enforcement score and the collateral-to-loan ratio. Furthermore, we also show that there is a significant positive correlation between the average proportion of firms in a country whose credit does not require collateral (with cash flow-based debt) with GDP per worker and TFP, but not with the debt-to-GDP ratio. We build a model that takes into account country characteristics in the proportion of firms whose loans require collateral and also in the average collateral-to-loan ratio. We find that policies aimed at increasing the proportion of firms that face borrowing constraints based on earnings rather than on assets, so as to reduce the misallocation of debt, may be as important as those aimed at reducing the collateral-to-loan ratio.
{"title":"Borrowing constraints, financial frictions, misallocation and GDP per worker","authors":"Amaia Iza, Ibai Ostolozaga","doi":"10.1016/j.jmacro.2024.103660","DOIUrl":"10.1016/j.jmacro.2024.103660","url":null,"abstract":"<div><div>The aim of this paper is to analyze the effect of relaxing borrowing constraints taking into account that firms may be facing either earnings-based or asset-based borrowing constraints on some aggregates such GDP per worker or TFP. We also analyze the impact on those aggregates of increasing the proportion of firms with earnings-based borrowing constraints. Using the World Bank Enterprise Survey, we show that the proportion of firms whose loans require collateral is lower in those countries whose bankruptcy laws facilitate reorganization. In addition, we show that there are no significant differences in the median/average contract-enforcement scores between countries where bankruptcy laws facilitate reorganization and countries where they do not, and that there is a significant negative link between the contract-enforcement score and the collateral-to-loan ratio. Furthermore, we also show that there is a significant positive correlation between the average proportion of firms in a country whose credit does not require collateral (with cash flow-based debt) with GDP per worker and TFP, but not with the debt-to-GDP ratio. We build a model that takes into account country characteristics in the proportion of firms whose loans require collateral and also in the average collateral-to-loan ratio. We find that policies aimed at increasing the proportion of firms that face borrowing constraints based on earnings rather than on assets, so as to reduce the misallocation of debt, may be as important as those aimed at reducing the collateral-to-loan ratio.</div></div>","PeriodicalId":47863,"journal":{"name":"Journal of Macroeconomics","volume":"83 ","pages":"Article 103660"},"PeriodicalIF":1.3,"publicationDate":"2025-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143173687","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 : 2025-01-07DOI: 10.1016/j.jmacro.2024.103659
Vlad Skovorodov , Rui Silva
We study the impact of the Public Sector Purchase Programme (PSPP) between 2015 and 2018 on lending volumes in the Eurozone. We find a connection between purchases under the PSPP and: (i) lending volumes on types of loans mainly obtained by SMEs; (ii) loans below 1 million euros during the expansion phase of the program until the end of 2016, and loans above 1 million euros in its contraction phase; (iii) substantial changes in lending volumes in economies with high levels of public debt and distressed financial systems, and; (iv) types of loans mainly obtained by SMEs in more resilient economies. These findings point to the effectiveness of the credit channel as a transmission mechanism of unconventional monetary policy and support the decision of the ECB to reactivate the program at the end of 2019.
{"title":"The impact of the Public Sector Purchase Programme on lending to SMEs","authors":"Vlad Skovorodov , Rui Silva","doi":"10.1016/j.jmacro.2024.103659","DOIUrl":"10.1016/j.jmacro.2024.103659","url":null,"abstract":"<div><div>We study the impact of the Public Sector Purchase Programme (PSPP) between 2015 and 2018 on lending volumes in the Eurozone. We find a connection between purchases under the PSPP and: (i) lending volumes on types of loans mainly obtained by SMEs; (ii) loans below 1 million euros during the expansion phase of the program until the end of 2016, and loans above 1 million euros in its contraction phase; (iii) substantial changes in lending volumes in economies with high levels of public debt and distressed financial systems, and; (iv) types of loans mainly obtained by SMEs in more resilient economies. These findings point to the effectiveness of the credit channel as a transmission mechanism of unconventional monetary policy and support the decision of the ECB to reactivate the program at the end of 2019.</div></div>","PeriodicalId":47863,"journal":{"name":"Journal of Macroeconomics","volume":"83 ","pages":"Article 103659"},"PeriodicalIF":1.3,"publicationDate":"2025-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143173688","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 : 2025-01-06DOI: 10.1016/j.jmacro.2024.103663
Ryoji Hiraguchi , Keiichiro Kobayashi
In this study, we construct a variant of the Lagos–Wright monetary model in which both buyers and sellers optimally decide whether to enter decentralized market by paying fixed entry costs. In the decentralized market, the sellers produce the intermediate inputs which are necessary to produce the general good traded in the centralized market. We show that the Friedman rule of setting nominal interest rate to zero may not be optimal. The optimal inflation rate is derived explicitly for specific functional forms. It is shown that the optimal inflation rate is lower for lower buyer entry costs, because the lower entry costs generate the buyer’s congestion leading to lower benefit from holding money, which must be balanced by lower cost of money holdings. It is also shown that the optimal inflation is lower for higher seller entry costs.
{"title":"Inflation and entry costs in a monetary search model","authors":"Ryoji Hiraguchi , Keiichiro Kobayashi","doi":"10.1016/j.jmacro.2024.103663","DOIUrl":"10.1016/j.jmacro.2024.103663","url":null,"abstract":"<div><div>In this study, we construct a variant of the Lagos–Wright monetary model in which both buyers and sellers optimally decide whether to enter decentralized market by paying fixed entry costs. In the decentralized market, the sellers produce the intermediate inputs which are necessary to produce the general good traded in the centralized market. We show that the Friedman rule of setting nominal interest rate to zero may not be optimal. The optimal inflation rate is derived explicitly for specific functional forms. It is shown that the optimal inflation rate is lower for lower buyer entry costs, because the lower entry costs generate the buyer’s congestion leading to lower benefit from holding money, which must be balanced by lower cost of money holdings. It is also shown that the optimal inflation is lower for higher seller entry costs.</div></div>","PeriodicalId":47863,"journal":{"name":"Journal of Macroeconomics","volume":"83 ","pages":"Article 103663"},"PeriodicalIF":1.3,"publicationDate":"2025-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143173788","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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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