Pub Date : 2021-03-17DOI: 10.14718/REVFINANZPOLITECON.V13.N1.2021.9
Michael Demmler, Amilcar Orlian Fernández Domínguez
This paper examines historical Bitcoin price data together with the price data of a well-known and generally accepted historical asset price bubble (the 1720 South Sea Bubble) with the aim of identifying possible similarities. In order to find empirical evidence of speculative bubble tendencies, the article analyses distribution moments and autoregressive models of time series of both assets. Results show that historical daily prices of both assets—taking into account one year before and one year after the maximum price level—clearly show the two phases of bubble expansion and subsequent crash. Furthermore, various similarities between the South Sea Bubble and Bitcoin can be found in descriptive statistics, such as mean of return, standard deviation, and skewness. Statistical tests also show several explosive moments in the time series of the South Sea Company and Bitcoin returns, which implies that both assets exhibit more than one financial bubble.
{"title":"Bitcoin and the South Sea Company: A comparative analysis","authors":"Michael Demmler, Amilcar Orlian Fernández Domínguez","doi":"10.14718/REVFINANZPOLITECON.V13.N1.2021.9","DOIUrl":"https://doi.org/10.14718/REVFINANZPOLITECON.V13.N1.2021.9","url":null,"abstract":"This paper examines historical Bitcoin price data together with the price data of a well-known and generally accepted historical asset price bubble (the 1720 South Sea Bubble) with the aim of identifying possible similarities. In order to find empirical evidence of speculative bubble tendencies, the article analyses distribution moments and autoregressive models of time series of both assets. Results show that historical daily prices of both assets—taking into account one year before and one year after the maximum price level—clearly show the two phases of bubble expansion and subsequent crash. Furthermore, various similarities between the South Sea Bubble and Bitcoin can be found in descriptive statistics, such as mean of return, standard deviation, and skewness. Statistical tests also show several explosive moments in the time series of the South Sea Company and Bitcoin returns, which implies that both assets exhibit more than one financial bubble.","PeriodicalId":377256,"journal":{"name":"Revista Finanzas y Política Económica","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114724485","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-03-17DOI: 10.14718/REVFINANZPOLITECON.V13.N1.2021.8
Diógenes Lagos Cortés, Rolando Roncancio Rachid
This work aims to analyze the relationship between management board independence and financial performance (variables ROA, ROE, and Tobin’s Q). Two perspectives on independence were used: (a) Law 964 of 2005 (mandatory in the Colombian stock market) and (b) an expanded view that included business relationships (cross-directorships, seniority on the board), financial relationships (compensation packages, ownership participation), and personal relationships (founders, members of the owner family) as factors that limit independence. Regression models (random effects) were used on an unbalanced data panel composed of 69 companies from the Colombian Stock Exchange. The results showed that a more rigorous definition of independence is better appreciated by the market. It was found that board independence does not affect accounting performance (ROA and ROE), but it does affect market performance (Tobin’s Q).
{"title":"Independencia de la junta directiva y desempeño financiero: evidencia de empresas colombianas","authors":"Diógenes Lagos Cortés, Rolando Roncancio Rachid","doi":"10.14718/REVFINANZPOLITECON.V13.N1.2021.8","DOIUrl":"https://doi.org/10.14718/REVFINANZPOLITECON.V13.N1.2021.8","url":null,"abstract":"This work aims to analyze the relationship between management board independence and financial performance (variables ROA, ROE, and Tobin’s Q). Two perspectives on independence were used: (a) Law 964 of 2005 (mandatory in the Colombian stock market) and (b) an expanded view that included business relationships (cross-directorships, seniority on the board), financial relationships (compensation packages, ownership participation), and personal relationships (founders, members of the owner family) as factors that limit independence. Regression models (random effects) were used on an unbalanced data panel composed of 69 companies from the Colombian Stock Exchange. The results showed that a more rigorous definition of independence is better appreciated by the market. It was found that board independence does not affect accounting performance (ROA and ROE), but it does affect market performance (Tobin’s Q).","PeriodicalId":377256,"journal":{"name":"Revista Finanzas y Política Económica","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125114662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-03-17DOI: 10.14718/REVFINANZPOLITECON.V13.N1.2021.1
Joan Miguel Tejedor Estupiñán
The pandemic caused by the SARS-CoV-2 virus had left, until December 2020, approximately 100,000,000 infected and 2,000,000 fatalities around the world (Johns Hopkins University and Medicine, 2020) . Nevertheless, as scientists and politicians from all around the world have warned, the consequences of this pandemic would expose the weaknesses of national health systems in the face of these types of global threats, as well as their level of response to the social side effects caused by global protection measures imposed by the World Health Organization.
{"title":"Vacunación y desarrollo en tiempos de la COVID-19","authors":"Joan Miguel Tejedor Estupiñán","doi":"10.14718/REVFINANZPOLITECON.V13.N1.2021.1","DOIUrl":"https://doi.org/10.14718/REVFINANZPOLITECON.V13.N1.2021.1","url":null,"abstract":"The pandemic caused by the SARS-CoV-2 virus had left, until December 2020, approximately 100,000,000 infected and 2,000,000 fatalities around the world (Johns Hopkins University and Medicine, 2020) . Nevertheless, as scientists and politicians from all around the world have warned, the consequences of this pandemic would expose the weaknesses of national health systems in the face of these types of global threats, as well as their level of response to the social side effects caused by global protection measures imposed by the World Health Organization.","PeriodicalId":377256,"journal":{"name":"Revista Finanzas y Política Económica","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116090638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-03-17DOI: 10.14718/REVFINANZPOLITECON.V13.N1.2021.2
Hector Darío Balseiro Barrios, Jorge Armando Luna Amador, Francisco Javier Maza Ávila
This paper aims to evaluate the financial efficiency of 69 companies listed in the Colombian stock market between 2012 and 2017, to understand how these organizations carry out the optimal allocation of resources. For this purpose, data envelopment analysis (DEA)—CCR, BCC, and EE models—is applied to the following variables: operating income, property, plant and equipment, investments, and inventories. The results showed that most of the companies did not efficiently allocate their resources during the considered period, given that, on average, only 17 companies (26.82%) achieved efficiency, and only 6 of them maintained it uninterruptedly. Moreover, the study concludes that the scale type used by companies is not determinant in the efficiency result obtained.
{"title":"Análisis de eficiencia financiera de las empresas cotizantes en el mercado accionario colombiano para el periodo 2012- 2017","authors":"Hector Darío Balseiro Barrios, Jorge Armando Luna Amador, Francisco Javier Maza Ávila","doi":"10.14718/REVFINANZPOLITECON.V13.N1.2021.2","DOIUrl":"https://doi.org/10.14718/REVFINANZPOLITECON.V13.N1.2021.2","url":null,"abstract":"This paper aims to evaluate the financial efficiency of 69 companies listed in the Colombian stock market between 2012 and 2017, to understand how these organizations carry out the optimal allocation of resources. For this purpose, data envelopment analysis (DEA)—CCR, BCC, and EE models—is applied to the following variables: operating income, property, plant and equipment, investments, and inventories. The results showed that most of the companies did not efficiently allocate their resources during the considered period, given that, on average, only 17 companies (26.82%) achieved efficiency, and only 6 of them maintained it uninterruptedly. Moreover, the study concludes that the scale type used by companies is not determinant in the efficiency result obtained.","PeriodicalId":377256,"journal":{"name":"Revista Finanzas y Política Económica","volume":"118 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123234303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-03-17DOI: 10.14718/REVFINANZPOLITECON.V13.N1.2021.10
Luis Améstica Rivas, Andrea King Domínguez, Viviana Moraga Dionicio, Rodrigo Romero Romero
The main objective of this research is to determine whether characteristics of the composition of the board of directors, such as percentage of women, board independence, or size and ownership concentration in the Latin American Integrated Market (MILA), contribute to the economic performance of companies. The ROA, ROE, and Tobin’s Q were used as performance measures. This study performs a regression analysis using the Tobit Model, with dynamic and static panel data with fixed effects, on a sample of 83 companies. Finally, evidence was found that both board size and ownership concentration influence the performance of companies.
{"title":"Influencia del directorio en el desempeño del Mercado Integrado Latinoamericano","authors":"Luis Améstica Rivas, Andrea King Domínguez, Viviana Moraga Dionicio, Rodrigo Romero Romero","doi":"10.14718/REVFINANZPOLITECON.V13.N1.2021.10","DOIUrl":"https://doi.org/10.14718/REVFINANZPOLITECON.V13.N1.2021.10","url":null,"abstract":"The main objective of this research is to determine whether characteristics of the composition of the board of directors, such as percentage of women, board independence, or size and ownership concentration in the Latin American Integrated Market (MILA), contribute to the economic performance of companies. The ROA, ROE, and Tobin’s Q were used as performance measures. This study performs a regression analysis using the Tobit Model, with dynamic and static panel data with fixed effects, on a sample of 83 companies. Finally, evidence was found that both board size and ownership concentration influence the performance of companies.","PeriodicalId":377256,"journal":{"name":"Revista Finanzas y Política Económica","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129300239","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-03-17DOI: 10.14718/REVFINANZPOLITECON.V13.N1.2021.3
José Luis Hernández Mota, Iván Abdel Marín Medrano
This paper aims to analyze public investment spending with sustainable external financing. The theoretical section examines solvency and fiscal compliance conditions that allow determining a rule for sustainable debt accumulation with a public investment policy. Empirically, a fiscal reaction function is estimated, which validates the hypothesis of positive effects of the implementation of the rule on primary balance and phy-sical budgetary investment for the period 1990:I-2019:IV. The results suggest discussing the relevance of modifying debt and public spending policy in order to stimulate economic activity.
{"title":"Financiamiento sostenible de la inversión pública: evidencia para México, 2001-2019","authors":"José Luis Hernández Mota, Iván Abdel Marín Medrano","doi":"10.14718/REVFINANZPOLITECON.V13.N1.2021.3","DOIUrl":"https://doi.org/10.14718/REVFINANZPOLITECON.V13.N1.2021.3","url":null,"abstract":"This paper aims to analyze public investment spending with sustainable external financing. The theoretical section examines solvency and fiscal compliance conditions that allow determining a rule for sustainable debt accumulation with a public investment policy. Empirically, a fiscal reaction function is estimated, which validates the hypothesis of positive effects of the implementation of the rule on primary balance and phy-sical budgetary investment for the period 1990:I-2019:IV. The results suggest discussing the relevance of modifying debt and public spending policy in order to stimulate economic activity.","PeriodicalId":377256,"journal":{"name":"Revista Finanzas y Política Económica","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115738434","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-03-17DOI: 10.14718/REVFINANZPOLITECON.V13.N1.2021.6
Lorena Sotelo Forero, L. E. Vallejo Zamudio
This paper aims to explain the relationship between labor policy and job creation in the industrial sector in Colombia in the period 2010-2018. To the effect, it first examines the topic of labor in the development plans of the two administrations of former president Juan Manuel Santos. First, a diagnostic analysis of industrial employment is carried out for the study period based on data of the Annual Manufacturing Survey (EAM, for its acronym in Spanish) administered by the National Administrative Department of Statistics of Colombia (DANE, for its acronym in Spanish). Second, the characteristics of industrial employment creation are examined, emphasizing the evolution of its participation in total employment and its growth, as well as the importance of industrial subsectors in job creation, and how the nine main Colombian cities participate in it through these subsectors. One of the most important conclusions is that industrial employment in Colombia has responded to conjunctural changes (world economy slowdown, exchange rate revaluation, market closure in Venezuela), as well as to changes occurred since economic opening in labor issues, which sought to implement greater flexibility in the labor market.
{"title":"La generación de empleo en el sector industrial en Colombia 2010-2018","authors":"Lorena Sotelo Forero, L. E. Vallejo Zamudio","doi":"10.14718/REVFINANZPOLITECON.V13.N1.2021.6","DOIUrl":"https://doi.org/10.14718/REVFINANZPOLITECON.V13.N1.2021.6","url":null,"abstract":"This paper aims to explain the relationship between labor policy and job creation in the industrial sector in Colombia in the period 2010-2018. To the effect, it first examines the topic of labor in the development plans of the two administrations of former president Juan Manuel Santos. First, a diagnostic analysis of industrial employment is carried out for the study period based on data of the Annual Manufacturing Survey (EAM, for its acronym in Spanish) administered by the National Administrative Department of Statistics of Colombia (DANE, for its acronym in Spanish). Second, the characteristics of industrial employment creation are examined, emphasizing the evolution of its participation in total employment and its growth, as well as the importance of industrial subsectors in job creation, and how the nine main Colombian cities participate in it through these subsectors. One of the most important conclusions is that industrial employment in Colombia has responded to conjunctural changes (world economy slowdown, exchange rate revaluation, market closure in Venezuela), as well as to changes occurred since economic opening in labor issues, which sought to implement greater flexibility in the labor market.","PeriodicalId":377256,"journal":{"name":"Revista Finanzas y Política Económica","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117009419","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-06DOI: 10.14718/REVNNANZPORITECON.V13.N1.2021.2
Hector Darío Balseiro Barrios, J. Amador, Francisco Javier Mazar Ávila
This paper aims to evaluate the financial efficiency of 69 Colombian companies listed on the stock market between 2012 and 2017, to understand how these organizations carry out the optimal allocation of resources. For this purpose, data envelopment analysis (DEA)—CCR, BCC, and EE models—is applied to the following variables: operating income, property, plant and equipment, investments, and inventories. The results showed that most of the companies did not efficiently allocate their resources during the considered period, given that, on average, only 17 companies (26.82%) achieved efficiency, and only 6 of them maintained it uninterruptedly. Moreover, the study concludes that the scale type used by companies is not determinant in the efficiency result obtained.
{"title":"Financial Efficiency Analysis of Listed Companies in the Colombian Stock Market Between 2012 and 2017","authors":"Hector Darío Balseiro Barrios, J. Amador, Francisco Javier Mazar Ávila","doi":"10.14718/REVNNANZPORITECON.V13.N1.2021.2","DOIUrl":"https://doi.org/10.14718/REVNNANZPORITECON.V13.N1.2021.2","url":null,"abstract":"This paper aims to evaluate the financial efficiency of 69 Colombian companies listed on the stock market between 2012 and 2017, to understand how these organizations carry out the optimal allocation of resources. For this purpose, data envelopment analysis (DEA)—CCR, BCC, and EE models—is applied to the following variables: operating income, property, plant and equipment, investments, and inventories. The results showed that most of the companies did not efficiently allocate their resources during the considered period, given that, on average, only 17 companies (26.82%) achieved efficiency, and only 6 of them maintained it uninterruptedly. Moreover, the study concludes that the scale type used by companies is not determinant in the efficiency result obtained.","PeriodicalId":377256,"journal":{"name":"Revista Finanzas y Política Económica","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134454258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-10-13DOI: 10.14718/REVFINANZPOLITECON.V12.N2.2020.3730
Joan Miguel Tejedor-Estupiñán
Durante la historia, la humanidad ha tenido que afrontar, investigar y superar innumerables enfermedades infecciosas las cuales han tenido alcances de epidemia y de pandemia. Existen datos de muchas epidemias de influenza como la que se expandio por Mesopotamia y Asia meridional, hacia el 1200 a C., hasta la pandemia de gripe de influenza (1889-1890); diversas epidemias de pestes bubonicas producidas por el patogeno yersinia pestis, como la plaga de Justiniano (541-542), que se origino en el Imperio Romano y se extendio en Europa y Asia del Este, la Peste Negra (1346-1356), la Plaga Rusa (1770-1772), entre otras epidemias de este patogeno que se expandieron por diversas ciudades de Europa, Africa, y Norte America durante el siglo XVI y XVII.
{"title":"Los impactos sociales y económicos de la pandemia de la Covid-19 en Latinoamérica","authors":"Joan Miguel Tejedor-Estupiñán","doi":"10.14718/REVFINANZPOLITECON.V12.N2.2020.3730","DOIUrl":"https://doi.org/10.14718/REVFINANZPOLITECON.V12.N2.2020.3730","url":null,"abstract":"Durante la historia, la humanidad ha tenido que afrontar, investigar y superar innumerables enfermedades infecciosas las cuales han tenido alcances de epidemia y de pandemia. Existen datos de muchas epidemias de influenza como la que se expandio por Mesopotamia y Asia meridional, hacia el 1200 a C., hasta la pandemia de gripe de influenza (1889-1890); diversas epidemias de pestes bubonicas producidas por el patogeno yersinia pestis, como la plaga de Justiniano (541-542), que se origino en el Imperio Romano y se extendio en Europa y Asia del Este, la Peste Negra (1346-1356), la Plaga Rusa (1770-1772), entre otras epidemias de este patogeno que se expandieron por diversas ciudades de Europa, Africa, y Norte America durante el siglo XVI y XVII.","PeriodicalId":377256,"journal":{"name":"Revista Finanzas y Política Económica","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123803733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-08-14DOI: 10.14718/REVFINANZPOLITECON.V12.N2.2020.3079
A. Rodríguez-Romero, M. Torres-Ortiz
This article aims to estimate whether there is an asymmetric transmission of changes in the wholesale prices of various foods to consumer prices in Bogota, and what relationship it may have with the degree of perishability. For this purpose, the evolution of prices and gross margin was characterized based on volatility and the ADF unit root test; the Koyck model was estimated to quantify the contemporary effect of a wholesale price change, the speed of adjustment, the number of months to reach half of the final impact, and the value of that impact. Finally, a model was estimated to differentiate the effect of an increase and a decrease in wholesale prices. For non-perishable foods, greater volatility was recorded in the gross margin, less transmission of the magnitude of the change, greater sensitivity to increases, and asymmetry in transmission.
{"title":"Transmisión entre precios de los alimentos en Bogotá, 2000-2017","authors":"A. Rodríguez-Romero, M. Torres-Ortiz","doi":"10.14718/REVFINANZPOLITECON.V12.N2.2020.3079","DOIUrl":"https://doi.org/10.14718/REVFINANZPOLITECON.V12.N2.2020.3079","url":null,"abstract":"This article aims to estimate whether there is an asymmetric transmission of changes in the wholesale prices of various foods to consumer prices in Bogota, and what relationship it may have with the degree of perishability. For this purpose, the evolution of prices and gross margin was characterized based on volatility and the ADF unit root test; the Koyck model was estimated to quantify the contemporary effect of a wholesale price change, the speed of adjustment, the number of months to reach half of the final impact, and the value of that impact. Finally, a model was estimated to differentiate the effect of an increase and a decrease in wholesale prices. For non-perishable foods, greater volatility was recorded in the gross margin, less transmission of the magnitude of the change, greater sensitivity to increases, and asymmetry in transmission.","PeriodicalId":377256,"journal":{"name":"Revista Finanzas y Política Económica","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128946359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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