Finance in Transition discusses the transition from traditional finance to transition finance.The current pattern of unsustainable economic development is supported by the global financial system, whose goal function is to create ever more financial value. Traditional finance is based on the concept of shareholder value. This paper develops new principles for a sustainable financial system. These guiding principles are: 1) from shareholder to integrated value, which combines financial, social and environmental value; 2) stewardship based on a direct link between financiers and companies; and 3) capital allocation based on long-term societal value.
{"title":"Finance in Transition","authors":"D. Loorbach, D. Schoenmaker, Willem Schramade","doi":"10.1596/33075","DOIUrl":"https://doi.org/10.1596/33075","url":null,"abstract":"Finance in Transition discusses the transition from traditional finance to transition finance.The current pattern of unsustainable economic development is supported by the global financial system, whose goal function is to create ever more financial value. Traditional finance is based on the concept of shareholder value. \u0000 \u0000This paper develops new principles for a sustainable financial system. These guiding principles are: 1) from shareholder to integrated value, which combines financial, social and environmental value; 2) stewardship based on a direct link between financiers and companies; and 3) capital allocation based on long-term societal value.","PeriodicalId":284021,"journal":{"name":"International Political Economy: Investment & Finance eJournal","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126937401","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}
What shapes and drives capital market development over the long run? In this paper, using the asset portfolios of UK life assurers, we examine the role of regulation, historical contingency, and political reactions to events on the long-run development of the UK capital market. Government response to events such as war, hegemony-secured peace, and the wider macroeconomic environment was the ultimate determinant of major changes in asset allocation since 1800. Furthermore, when we compare the UK with the United States, we find that regulation played a limited role in shaping the asset portfolios of the UK life assurance industry.
{"title":"Capital Market Development Over the Long Run: The Portfolios of UK Life Assurers Over Two Centuries","authors":"D. Bogle, Christopher Coyle, J. Turner","doi":"10.2139/ssrn.3728922","DOIUrl":"https://doi.org/10.2139/ssrn.3728922","url":null,"abstract":"\u0000 What shapes and drives capital market development over the long run? In this paper, using the asset portfolios of UK life assurers, we examine the role of regulation, historical contingency, and political reactions to events on the long-run development of the UK capital market. Government response to events such as war, hegemony-secured peace, and the wider macroeconomic environment was the ultimate determinant of major changes in asset allocation since 1800. Furthermore, when we compare the UK with the United States, we find that regulation played a limited role in shaping the asset portfolios of the UK life assurance industry.","PeriodicalId":284021,"journal":{"name":"International Political Economy: Investment & Finance eJournal","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132964038","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}
We simulate the evolution of stylised loan portfolios to assess the impact of IFRS 9 and US-GAAP expected loss model (ECL) on the pro-cyclicality of realised losses and capital ratios of banks, relative to the incurred loss model of IAS 39. We focus on the interaction between the changes in loan loss provisions (LLPs) charges (flow channel) and stocks (stock channel) under ECL. Our results show that ECL model smooths the impact of credit losses on profits and capital resources, reducing the pro-cyclicality of capital and leverage ratios, especially under US GAAP. However, when GDP is highly volatile, the large differences in lifetime probabilities of defaults (PDs) between booms and bust cause sharp increases in LLPs in deep downturns, as seen for US banks during the COVID-19 crisis. Volatile GDP makes capital and leverage ratios more pro-cyclical and cause sharper falls in both ratios in deep downturns under US GAAP, compared to IAS 39. IFRS 9 ECL shows less sensitivity to lifetime PDs fluctuations due to the existence of loan stages, and hence reduces the pro-cyclicality of capital and leverage ratios even when GDP is highly volatile.
{"title":"Expected Loss Model and the Cyclicality of Bank Credit Losses and Capital Ratios","authors":"Mahmoud Fatouh, S. Giansante","doi":"10.2139/ssrn.3728699","DOIUrl":"https://doi.org/10.2139/ssrn.3728699","url":null,"abstract":"We simulate the evolution of stylised loan portfolios to assess the impact of IFRS 9 and US-GAAP expected loss model (ECL) on the pro-cyclicality of realised losses and capital ratios of banks, relative to the incurred loss model of IAS 39. We focus on the interaction between the changes in loan loss provisions (LLPs) charges (flow channel) and stocks (stock channel) under ECL. Our results show that ECL model smooths the impact of credit losses on profits and capital resources, reducing the pro-cyclicality of capital and leverage ratios, especially under US GAAP. However, when GDP is highly volatile, the large differences in lifetime probabilities of defaults (PDs) between booms and bust cause sharp increases in LLPs in deep downturns, as seen for US banks during the COVID-19 crisis. Volatile GDP makes capital and leverage ratios more pro-cyclical and cause sharper falls in both ratios in deep downturns under US GAAP, compared to IAS 39. IFRS 9 ECL shows less sensitivity to lifetime PDs fluctuations due to the existence of loan stages, and hence reduces the pro-cyclicality of capital and leverage ratios even when GDP is highly volatile.","PeriodicalId":284021,"journal":{"name":"International Political Economy: Investment & Finance eJournal","volume":"102 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124701222","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}
Equity exchanges typically subsidize liquidity providers through a rebate, and charge liquidity demanders a fee. We model the impact of this asymmetric fee structure in a setting where some traders pay fees directly to the exchange--a "maker-taker trader"--while others incur a flat fee per trade (e.g., through a broker commission). When the fraction of flat-fee traders is sufficiently small, only the total exchange fee per transaction has an economic impact. If sufficiently many investors face flat commissions, however, trading volume and investor welfare fall, with maker-taker traders assuming a de-facto market-maker role. Moreover, maker-taker traders earn higher average profits.
{"title":"Maker-Taker Fees and Liquidity: The Role of Commission Structures","authors":"Michael Brolley, Katya Malinova","doi":"10.2139/ssrn.3726190","DOIUrl":"https://doi.org/10.2139/ssrn.3726190","url":null,"abstract":"Equity exchanges typically subsidize liquidity providers through a rebate, and charge liquidity demanders a fee. We model the impact of this asymmetric fee structure in a setting where some traders pay fees directly to the exchange--a \"maker-taker trader\"--while others incur a flat fee per trade (e.g., through a broker commission). When the fraction of flat-fee traders is sufficiently small, only the total exchange fee per transaction has an economic impact. If sufficiently many investors face flat commissions, however, trading volume and investor welfare fall, with maker-taker traders assuming a de-facto market-maker role. Moreover, maker-taker traders earn higher average profits.","PeriodicalId":284021,"journal":{"name":"International Political Economy: Investment & Finance eJournal","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130810844","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}
Borrowing fees set in the securities lending market contain reliable information about the cross section of short-term expected stock returns. Using securities lending data for 14 developed and emerging markets from 2011 to 2018, we find that stocks with high borrowing fees tend to underperform their peers over the short term. Moreover, stocks that remain expensive to borrow continue to underperform, but persistence of high borrowing fees is not systematically predictable. While the information in borrowing fees is fast decaying, it can still be efficiently incorporated into real-world equity portfolios.
{"title":"Borrowing Fees and Expected Stock Returns","authors":"Kaitlin Hendrix, Gavin Crabb","doi":"10.2139/ssrn.3726227","DOIUrl":"https://doi.org/10.2139/ssrn.3726227","url":null,"abstract":"Borrowing fees set in the securities lending market contain reliable information about the cross section of short-term expected stock returns. Using securities lending data for 14 developed and emerging markets from 2011 to 2018, we find that stocks with high borrowing fees tend to underperform their peers over the short term. Moreover, stocks that remain expensive to borrow continue to underperform, but persistence of high borrowing fees is not systematically predictable. While the information in borrowing fees is fast decaying, it can still be efficiently incorporated into real-world equity portfolios.","PeriodicalId":284021,"journal":{"name":"International Political Economy: Investment & Finance eJournal","volume":"353 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132103959","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}
Unlike public markets, private market holdings are a class of self-liquidating assets. Consequently, there is no passive strategy, e.g., buy-and-hold, to invest in private markets. All investments require an active management. In order to build and maintain a desired allocation to private markets one needs a commitment pacing plan that balances several objectives including stable exposure, performance, cash flow management, diversification over funds and time, and maintaining relationships with GPs.
A good commitment pacing plan is often seen as the lynchpin of a private capital program and can account for much of the dispersion in performance across LPs. We present a simulation-based framework to show the tradeoff between the steady-state NAV and the speed with which it can be built using a simple, yet powerful, commitment strategy and a popular cash flow model. Our framework also reveals the tradeoff between liquidity and risk-adjusted performance assuming the existence of private market premium in US buyout investments.
{"title":"Building and Maintaining a Desired Exposure to Private Markets: Commitment Pacing, Cash Flow Modeling, and Beyond","authors":"V. Jeet","doi":"10.2139/ssrn.3775003","DOIUrl":"https://doi.org/10.2139/ssrn.3775003","url":null,"abstract":"Unlike public markets, private market holdings are a class of self-liquidating assets. Consequently, there is no passive strategy, e.g., buy-and-hold, to invest in private markets. All investments require an active management. In order to build and maintain a desired allocation to private markets one needs a commitment pacing plan that balances several objectives including stable exposure, performance, cash flow management, diversification over funds and time, and maintaining relationships with GPs.<br><br>A good commitment pacing plan is often seen as the lynchpin of a private capital program and can account for much of the dispersion in performance across LPs. We present a simulation-based framework to show the tradeoff between the steady-state NAV and the speed with which it can be built using a simple, yet powerful, commitment strategy and a popular cash flow model. Our framework also reveals the tradeoff between liquidity and risk-adjusted performance assuming the existence of private market premium in US buyout investments.","PeriodicalId":284021,"journal":{"name":"International Political Economy: Investment & Finance eJournal","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114928853","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}
Abstract We examine gender differences in financial literacy among high school students in Italy using data from the 2012 Programme for International Student Assessment (PISA). Gender differences in financial literacy are large among the young in Italy. They are present in all regions and are particularly severe in the South and the Islands. Combining the rich PISA data with a variety of other indicators, we provide a thorough analysis of the potential determinants of the gender gap in financial literacy. We find that parental background, in particular the role of mothers, matters for the financial knowledge of girls. Moreover, we show that the social and cultural environment in which girls and boys live plays a crucial role in explaining gender differences. We also show that history matters: Medieval commercial hubs and the nuclear family structure created conditions favorable to the transformation of the role of women in society, and shaped gender differences in financial literacy as well. We discuss the changes that are needed to close the gap in financial knowledge among the young.
{"title":"Stereotypes in Financial Literacy: Evidence from PISA","authors":"L. Bottazzi, A. Lusardi","doi":"10.3386/w28065","DOIUrl":"https://doi.org/10.3386/w28065","url":null,"abstract":"Abstract We examine gender differences in financial literacy among high school students in Italy using data from the 2012 Programme for International Student Assessment (PISA). Gender differences in financial literacy are large among the young in Italy. They are present in all regions and are particularly severe in the South and the Islands. Combining the rich PISA data with a variety of other indicators, we provide a thorough analysis of the potential determinants of the gender gap in financial literacy. We find that parental background, in particular the role of mothers, matters for the financial knowledge of girls. Moreover, we show that the social and cultural environment in which girls and boys live plays a crucial role in explaining gender differences. We also show that history matters: Medieval commercial hubs and the nuclear family structure created conditions favorable to the transformation of the role of women in society, and shaped gender differences in financial literacy as well. We discuss the changes that are needed to close the gap in financial knowledge among the young.","PeriodicalId":284021,"journal":{"name":"International Political Economy: Investment & Finance eJournal","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131373467","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 : 2020-10-30DOI: 10.47752/SJEF.310.178.188
J. Ugoani
Credit risk management is central to the success or failure of a banking institution because banks earn the greatest quantum of their interest income from interest on loans which represents a critical component of a bank’s profitability. Therefore, any carelessness with regard to credit risk management automatically results to creating huge nonperforming loans which often prepares the grounds for bank distress or failure. In the 1990s and specifically in 1995, 50 percent of 120 banks became technically distressed, as they were characterized by poor management and weak liquidity ratio. For example, in 1995, the ratio of nonperforming loans to total loans was about 33 percent compared to about 5 percent in 2015, and the average liquidity ratio of banks in 1995 was 0.49, against 58.18 in 2015. Also the loans, to deposit ratio in 1995 was 58.4 and 73.21 in 2015, while the number of banks with average liquidity ratio of less than 30 percent was 50 in 1995 against 1 in 2015. Distress persisted in the Nigerian banking system in the 1990s with dwindling profitability and the erosion of shareholders’ equity. In 1995, the adjusted shareholders funds was – N8791.1million against N3,240 billion in 2015, while the capital to total risk weighted asset ratio was about 67.18 percent in 1995 and only about 17.66 percent in 2015. In 1995, the ratio of nonperforming loans to shareholders’ funds was about 496 percent against about 13 percent in 2015. These major performance indicators showed that there was improved credit risk management and bank management effectiveness after 1995 until 2015. The expo-facto research design was employed for the study and the result showed strong positive relationship between credit risk evaluation management and bank management effectiveness. The study was not exhaustive, and further research could examine the relationship between regulatory efficiency and the performance of deposit money banks in Nigeria. The board of directors of banks should always take measures to avoid lending arrangements over and above the repayment capacity of borrowers to reduce the creation of nonperforming loans.
{"title":"Credit Risk Management Evaluation and Bank Management Effectiveness: 1995–2015 Dimensionality","authors":"J. Ugoani","doi":"10.47752/SJEF.310.178.188","DOIUrl":"https://doi.org/10.47752/SJEF.310.178.188","url":null,"abstract":"Credit risk management is central to the success or failure of a banking institution because banks earn the greatest quantum of their interest income from interest on loans which represents a critical component of a bank’s profitability. Therefore, any carelessness with regard to credit risk management automatically results to creating huge nonperforming loans which often prepares the grounds for bank distress or failure. In the 1990s and specifically in 1995, 50 percent of 120 banks became technically distressed, as they were characterized by poor management and weak liquidity ratio. For example, in 1995, the ratio of nonperforming loans to total loans was about 33 percent compared to about 5 percent in 2015, and the average liquidity ratio of banks in 1995 was 0.49, against 58.18 in 2015. Also the loans, to deposit ratio in 1995 was 58.4 and 73.21 in 2015, while the number of banks with average liquidity ratio of less than 30 percent was 50 in 1995 against 1 in 2015. Distress persisted in the Nigerian banking system in the 1990s with dwindling profitability and the erosion of shareholders’ equity. In 1995, the adjusted shareholders funds was – N8791.1million against N3,240 billion in 2015, while the capital to total risk weighted asset ratio was about 67.18 percent in 1995 and only about 17.66 percent in 2015. In 1995, the ratio of nonperforming loans to shareholders’ funds was about 496 percent against about 13 percent in 2015. These major performance indicators showed that there was improved credit risk management and bank management effectiveness after 1995 until 2015. The expo-facto research design was employed for the study and the result showed strong positive relationship between credit risk evaluation management and bank management effectiveness. The study was not exhaustive, and further research could examine the relationship between regulatory efficiency and the performance of deposit money banks in Nigeria. The board of directors of banks should always take measures to avoid lending arrangements over and above the repayment capacity of borrowers to reduce the creation of nonperforming loans.","PeriodicalId":284021,"journal":{"name":"International Political Economy: Investment & Finance eJournal","volume":"744 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122962555","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}
Modern central bankers confront a challenge of providing economic stimulus even when the policy rate is constrained by a lower bound. This challenge has led to substantial innovation by policymakers and a proliferation of new policy tools. In this paper, I offer evidence on the efficacy of a new tool known as funding for lending, which provides banks with subsidized funding to make additional loans. I focus on a historical episode from the United States in which the Federal Reserve provided banks with steeply subsidized loans to promote the expansion of credit within their local communities. I show that the cheap funding succeeded in generating more lending by countering banks' excessive liquidity preference. The additional credit benefited the real economy. Local areas enjoyed higher rates of small business formation and more rapid employment growth. Finally, I show that the cost of the subsidy provided by the government was more than offset by the additional payroll taxes paid out of higher wages and salaries. These results suggest that funding for lending programs deserve consideration for the modern central banker's toolkit and demonstrate that certain unconventional tools can offer monetary policymakers the means to pursue more targeted objectives.
{"title":"Can the Federal Reserve Effectively Target Main Street? Evidence from the 1970s Recession","authors":"John Kandrac","doi":"10.17016/FEDS.2021.061","DOIUrl":"https://doi.org/10.17016/FEDS.2021.061","url":null,"abstract":"Modern central bankers confront a challenge of providing economic stimulus even when the policy rate is constrained by a lower bound. This challenge has led to substantial innovation by policymakers and a proliferation of new policy tools. In this paper, I offer evidence on the efficacy of a new tool known as funding for lending, which provides banks with subsidized funding to make additional loans. I focus on a historical episode from the United States in which the Federal Reserve provided banks with steeply subsidized loans to promote the expansion of credit within their local communities. I show that the cheap funding succeeded in generating more lending by countering banks' excessive liquidity preference. The additional credit benefited the real economy. Local areas enjoyed higher rates of small business formation and more rapid employment growth. Finally, I show that the cost of the subsidy provided by the government was more than offset by the additional payroll taxes paid out of higher wages and salaries. These results suggest that funding for lending programs deserve consideration for the modern central banker's toolkit and demonstrate that certain unconventional tools can offer monetary policymakers the means to pursue more targeted objectives.","PeriodicalId":284021,"journal":{"name":"International Political Economy: Investment & Finance eJournal","volume":"145 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129059271","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}
While the global coronavirus pandemic has put great strain on public finances across the world, it is those countries with weaker national currencies that will feel this pressure more strongly. There is a very real risk of national defaults and of a mutually reinforcing downward spiral of reduced trade and competitive currency devaluations. To prevent the health crisis becoming a financial crisis we need a renegotiation of the global financial architecture to create new institutions that can uphold stability, equity and sustainability between the world’s economies. Next year marks 50 years since the ending of the Bretton Woods arrangements and provides an ideal platform for such a negotiation.
{"title":"Building Global Finance Back Better: Using the Coronavirus Pandemic as a Platform to Redesign the Global Financial Architecture","authors":"Molly Scott Cato","doi":"10.2139/ssrn.3712999","DOIUrl":"https://doi.org/10.2139/ssrn.3712999","url":null,"abstract":"While the global coronavirus pandemic has put great strain on public finances across the world, it is those countries with weaker national currencies that will feel this pressure more strongly. There is a very real risk of national defaults and of a mutually reinforcing downward spiral of reduced trade and competitive currency devaluations. To prevent the health crisis becoming a financial crisis we need a renegotiation of the global financial architecture to create new institutions that can uphold stability, equity and sustainability between the world’s economies. Next year marks 50 years since the ending of the Bretton Woods arrangements and provides an ideal platform for such a negotiation.","PeriodicalId":284021,"journal":{"name":"International Political Economy: Investment & Finance eJournal","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130356570","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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