I adapt the methods of Gurkaynak, Sack, and Swanson (2005) to estimate two dimensions of monetary policy during the 2009-2015 zero lower bound period in the U.S. I show that, after a suitable rotation, these two dimensions can be interpreted as "forward guidance" and "large-scale asset purchases" (LSAPs). I estimate the sizes of the forward guidance and LSAP components of each FOMC announcement between January 2009 and June 2015, and show that those estimates correspond closely to identifiable features of major FOMC announcements over that period. Forward guidance has relatively small effects on the longest-maturity Treasury yields and essentially no effect on corporate bond yields, while LSAPs have large effects on those yields but essentially no effect on short-term Treasuries. Both types of policies have significant effects on medium-term Treasury yields, stock prices, and exchange rates.
{"title":"Measuring the Effects of Unconventional Monetary Policy on Asset Prices","authors":"Eric T. Swanson","doi":"10.3386/w21816","DOIUrl":"https://doi.org/10.3386/w21816","url":null,"abstract":"I adapt the methods of Gurkaynak, Sack, and Swanson (2005) to estimate two dimensions of monetary policy during the 2009-2015 zero lower bound period in the U.S. I show that, after a suitable rotation, these two dimensions can be interpreted as \"forward guidance\" and \"large-scale asset purchases\" (LSAPs). I estimate the sizes of the forward guidance and LSAP components of each FOMC announcement between January 2009 and June 2015, and show that those estimates correspond closely to identifiable features of major FOMC announcements over that period. Forward guidance has relatively small effects on the longest-maturity Treasury yields and essentially no effect on corporate bond yields, while LSAPs have large effects on those yields but essentially no effect on short-term Treasuries. Both types of policies have significant effects on medium-term Treasury yields, stock prices, and exchange rates.","PeriodicalId":111923,"journal":{"name":"ERN: Monetary Policy (Topic)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131678953","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}
Recently, numerous Central Banks implement various macro-prudential policies to complement the existing monetary policy. This paper analyzes the impact of these policies along with the market structure, on the bank’s performance. Using panel data analysis, this paper conclude that the reserve requirement ratio policy negatively affect the bank’s performance (ROA). The empirical test shows the banking industry in Indonesia respond to the increase of reserve requirement by raising the Net Interest Margin to achieve their targeted operating profits. Secondly, this paper fail to find uniform conclusion across model variants about the effect of the policy rate on bank’s performance. This also applies on the Loan to Value policy. Fourth, the market concentration has a more significant effect on banks’ profitability as compared to market power. Fifth, the production index significantly affects the banking profitability. These findings implies a necessity for policy makers to review the financial market structure before formulating effective policy package to promote a healthy competition in the banking industry.
{"title":"The Market Structure of the Bank, Its Performance, and the Macroprudential Policy","authors":"T. Silalahi, A. Manurung, Y. Hidayat","doi":"10.21098/BEMP.V18I1.514","DOIUrl":"https://doi.org/10.21098/BEMP.V18I1.514","url":null,"abstract":"Recently, numerous Central Banks implement various macro-prudential policies to complement the existing monetary policy. This paper analyzes the impact of these policies along with the market structure, on the bank’s performance. Using panel data analysis, this paper conclude that the reserve requirement ratio policy negatively affect the bank’s performance (ROA). The empirical test shows the banking industry in Indonesia respond to the increase of reserve requirement by raising the Net Interest Margin to achieve their targeted operating profits. Secondly, this paper fail to find uniform conclusion across model variants about the effect of the policy rate on bank’s performance. This also applies on the Loan to Value policy. Fourth, the market concentration has a more significant effect on banks’ profitability as compared to market power. Fifth, the production index significantly affects the banking profitability. These findings implies a necessity for policy makers to review the financial market structure before formulating effective policy package to promote a healthy competition in the banking industry.","PeriodicalId":111923,"journal":{"name":"ERN: Monetary Policy (Topic)","volume":"45 7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117195493","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}
The goal of this paper is to examine the impact of crude oil price movements on two macro variables, the gross domestic product (GDP) growth rate and the consumer price index (CPI) inflation rate, in three countries, the People’s Republic of China (an emerging economy), Japan, and the United States (developed economies), in a model incorporating monetary variables (money supply and exchange rate). The main objective of this research is to investigate whether these economies are still reactive to oil price movements and compare their reactions. Monetary variables are included in this survey because our earlier research showed that they have a significant role in oil price determination. To assess the relationship between crude oil prices and macro variables we adopt an N-variable structural vector autoregression (SVAR) model. The results suggest that the impact of oil price fluctuations on developed oil importers’ GDP growth is much milder than on the GDP growth of an emerging economy. On the other hand, however, the impact of oil price fluctuations on the People’s Republic of China’s inflation rate was found to be milder than in the two developed countries that were examined.
{"title":"Macroeconomic Effects of Oil Price Fluctuations on Emerging and Developed Economies in a Model Incorporating Monetary Variables","authors":"Farhad Taghizadeh Hesary, N. Yoshino","doi":"10.2139/ssrn.2672783","DOIUrl":"https://doi.org/10.2139/ssrn.2672783","url":null,"abstract":"The goal of this paper is to examine the impact of crude oil price movements on two macro variables, the gross domestic product (GDP) growth rate and the consumer price index (CPI) inflation rate, in three countries, the People’s Republic of China (an emerging economy), Japan, and the United States (developed economies), in a model incorporating monetary variables (money supply and exchange rate). The main objective of this research is to investigate whether these economies are still reactive to oil price movements and compare their reactions. Monetary variables are included in this survey because our earlier research showed that they have a significant role in oil price determination. To assess the relationship between crude oil prices and macro variables we adopt an N-variable structural vector autoregression (SVAR) model. The results suggest that the impact of oil price fluctuations on developed oil importers’ GDP growth is much milder than on the GDP growth of an emerging economy. On the other hand, however, the impact of oil price fluctuations on the People’s Republic of China’s inflation rate was found to be milder than in the two developed countries that were examined.","PeriodicalId":111923,"journal":{"name":"ERN: Monetary Policy (Topic)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129756501","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}
The full text of this report is no longer available. For related work, see Fernando Duarte, “How to Escape a Liquidity Trap with Interest Rate Rules,” Federal Reserve Bank of New York Staff Reports, no. 776, May 2016.
{"title":"An Interest Rate Rule to Uniquely Implement the Optimal Equilibrium in a Liquidity Trap","authors":"Fernando M. Duarte, Anna Zabai","doi":"10.2139/ssrn.2672195","DOIUrl":"https://doi.org/10.2139/ssrn.2672195","url":null,"abstract":"The full text of this report is no longer available. For related work, see Fernando Duarte, “How to Escape a Liquidity Trap with Interest Rate Rules,” Federal Reserve Bank of New York Staff Reports, no. 776, May 2016.","PeriodicalId":111923,"journal":{"name":"ERN: Monetary Policy (Topic)","volume":"148 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122447512","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 : 2015-08-01DOI: 10.5089/9781513557595.001
Serkan Arslanalp, D. Botman
Portfolio rebalancing is a key transmission channel of quantitative easing in Japan. We construct a realistic rebalancing scenario, which suggests that the BoJ may need to taper its JGB purchases in 2017 or 2018, given collateral needs of banks, asset-liability management constraints of insurers, and announced asset allocation targets of major pension funds. Nonetheless, the BoJ could deliver continued monetary stimulus by extending the maturity of its JGB purchases or by scaling up private asset purchases. We quantify the impact of rebalancing on capital outflows and discuss JGB market signals that can be indicative of limits being within reach.
{"title":"Portfolio Rebalancing in Japan: Constraints and Implications for Quantitative Easing","authors":"Serkan Arslanalp, D. Botman","doi":"10.5089/9781513557595.001","DOIUrl":"https://doi.org/10.5089/9781513557595.001","url":null,"abstract":"Portfolio rebalancing is a key transmission channel of quantitative easing in Japan. We construct a realistic rebalancing scenario, which suggests that the BoJ may need to taper its JGB purchases in 2017 or 2018, given collateral needs of banks, asset-liability management constraints of insurers, and announced asset allocation targets of major pension funds. Nonetheless, the BoJ could deliver continued monetary stimulus by extending the maturity of its JGB purchases or by scaling up private asset purchases. We quantify the impact of rebalancing on capital outflows and discuss JGB market signals that can be indicative of limits being within reach.","PeriodicalId":111923,"journal":{"name":"ERN: Monetary Policy (Topic)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116864440","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}
This paper compares alternative monetary policy rules in a small open economy that experiences internal shocks (productivity shocks) and external shocks to terms of trade and the foreign demand. A comparison of the volatility of the macroeconomic variables such as inflation, output, terms of trade, trade balance, investment and exchange rates under the different monetary rules is set to lead to the choice of the optimal exchange rate regime. I will show that these regimes can be ranked in terms of their implied volatility for the considered macroeconomic variables. A two-country version of the Calvo sticky price model is used to analyze the macroeconomic implications of four alternative monetary policy regimes for a small open economy: domestic inflation targeting, managed float, CPI targeting and an exchange rate peg. The degree of exchange rate pass-through is very important for the assessment of monetary rules. I find that the CPI targeting rule is the best policy in an economy that exhibits lagged exchange rate pass-through. With low pass-through, both the domestic and the overall prices respond sluggishly to shocks, and it is more efficient for the monetary authority to target the overall CPI rather than just domestic prices. In a low pass-through environment, the policy maker can simultaneously strictly target (CPI) inflation, but still allow high volatility in the nominal exchange rate to stabilize the real economy in face of shocks. The low rate of pass-through ensures that exchange rate shocks do not destabilize the price level. An important feature of low pass-through is that it eliminates the trade-off between output volatility and inflation volatility in the comparison of fixed relative to floating exchange rates.
{"title":"Exchange Rate Dynamics and Monetary Policy in a Small Open Economy: A DSGE Model","authors":"M. Ouchen, Mustapha Ziky","doi":"10.2139/ssrn.2636906","DOIUrl":"https://doi.org/10.2139/ssrn.2636906","url":null,"abstract":"This paper compares alternative monetary policy rules in a small open economy that experiences internal shocks (productivity shocks) and external shocks to terms of trade and the foreign demand. A comparison of the volatility of the macroeconomic variables such as inflation, output, terms of trade, trade balance, investment and exchange rates under the different monetary rules is set to lead to the choice of the optimal exchange rate regime. I will show that these regimes can be ranked in terms of their implied volatility for the considered macroeconomic variables. A two-country version of the Calvo sticky price model is used to analyze the macroeconomic implications of four alternative monetary policy regimes for a small open economy: domestic inflation targeting, managed float, CPI targeting and an exchange rate peg. The degree of exchange rate pass-through is very important for the assessment of monetary rules. I find that the CPI targeting rule is the best policy in an economy that exhibits lagged exchange rate pass-through. With low pass-through, both the domestic and the overall prices respond sluggishly to shocks, and it is more efficient for the monetary authority to target the overall CPI rather than just domestic prices. In a low pass-through environment, the policy maker can simultaneously strictly target (CPI) inflation, but still allow high volatility in the nominal exchange rate to stabilize the real economy in face of shocks. The low rate of pass-through ensures that exchange rate shocks do not destabilize the price level. An important feature of low pass-through is that it eliminates the trade-off between output volatility and inflation volatility in the comparison of fixed relative to floating exchange rates.","PeriodicalId":111923,"journal":{"name":"ERN: Monetary Policy (Topic)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122225942","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}
No. And not only for the reason you think. In a world with multiple inefficiencies the single policy tool the central bank has control over will not undo all inefficiencies; this is well understood. We argue that the world is better characterized by multiple inefficiencies and multiple policy makers with various objectives. Asking the policy question only in terms of optimal monetary policy effectively turns the central bank into the residual claimant of all policy and gives the other policymakers a free hand in pursuing their own goals. This further worsens the tradeoffs faced by the central bank. The optimal monetary policy literature and the optimal simple rules often labeled flexible inflation targeting assign all of the cyclical policymaking duties to central banks. This distorts the policy discussion and narrows the policy choices to a suboptimal set. We highlight this issue and call for a broader thinking of optimal policies.
{"title":"Is Optimal Monetary Policy Always Optimal?","authors":"Troy A. Davig, R. Gürkaynak","doi":"10.2139/ssrn.2639830","DOIUrl":"https://doi.org/10.2139/ssrn.2639830","url":null,"abstract":"No. And not only for the reason you think. In a world with multiple inefficiencies the single policy tool the central bank has control over will not undo all inefficiencies; this is well understood. We argue that the world is better characterized by multiple inefficiencies and multiple policy makers with various objectives. Asking the policy question only in terms of optimal monetary policy effectively turns the central bank into the residual claimant of all policy and gives the other policymakers a free hand in pursuing their own goals. This further worsens the tradeoffs faced by the central bank. The optimal monetary policy literature and the optimal simple rules often labeled flexible inflation targeting assign all of the cyclical policymaking duties to central banks. This distorts the policy discussion and narrows the policy choices to a suboptimal set. We highlight this issue and call for a broader thinking of optimal policies.","PeriodicalId":111923,"journal":{"name":"ERN: Monetary Policy (Topic)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126601383","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}
This paper explores the impact of the adoption of inflation targeting (IT) on the dynamics of city-level inflation in Korea using both aggregate and sector-level data. When looking at aggregate regional inflation, we find that the mean, volatility and persistence fell in all cities in the wake of the monetary policy regime change, consistent with other evidence in the literature. We also note a narrowing of the dispersion of regional inflation across cities and a greater degree of regional co-movement. Delving more deeply into the disaggregate data reveals additional insights however. For most of the changes we observe in the dynamics of regional inflation, we find that the aggregate effects are being driven primarily by sectors that fall into the ‘Services’ category. We posit that the impact of better anchored inflationary expectations is primarily on the less-traded services sectors of the economy, where the domestic monetary policy framework has a relatively larger influence compared with globally-traded commodities. When it comes to the increased co-movement observed across regions under IT regime, however, it is the ‘Commodities’ sectors rather than ‘Services’ that are responsible, probably because services inflation becomes relatively more influenced by local factors once it has stabilized within the target range. We show that this sectoral heterogeneity can be explained by the difference in price stickiness such that sectors in which prices are adjusted less frequently tend to have a larger response under the new monetary policy regime.
{"title":"Monetary Policy Regime Change and Regional Inflation Dynamics: Looking Through the Lens of Sector-Level Data for Korea","authors":"Chi‐Young Choi, J. Lee, RóisÃn O'Sullivan","doi":"10.2139/ssrn.2636616","DOIUrl":"https://doi.org/10.2139/ssrn.2636616","url":null,"abstract":"This paper explores the impact of the adoption of inflation targeting (IT) on the dynamics of city-level inflation in Korea using both aggregate and sector-level data. When looking at aggregate regional inflation, we find that the mean, volatility and persistence fell in all cities in the wake of the monetary policy regime change, consistent with other evidence in the literature. We also note a narrowing of the dispersion of regional inflation across cities and a greater degree of regional co-movement. Delving more deeply into the disaggregate data reveals additional insights however. For most of the changes we observe in the dynamics of regional inflation, we find that the aggregate effects are being driven primarily by sectors that fall into the ‘Services’ category. We posit that the impact of better anchored inflationary expectations is primarily on the less-traded services sectors of the economy, where the domestic monetary policy framework has a relatively larger influence compared with globally-traded commodities. When it comes to the increased co-movement observed across regions under IT regime, however, it is the ‘Commodities’ sectors rather than ‘Services’ that are responsible, probably because services inflation becomes relatively more influenced by local factors once it has stabilized within the target range. We show that this sectoral heterogeneity can be explained by the difference in price stickiness such that sectors in which prices are adjusted less frequently tend to have a larger response under the new monetary policy regime.","PeriodicalId":111923,"journal":{"name":"ERN: Monetary Policy (Topic)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126254121","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}
The objective of the paper is to investigate whether the stock price reactions of commercial banks to monetary policy actions are dependent on the state of the economy. The results indicate that monetary policy actions have asymmetric effects on the returns of commercial banks across different monetary policy and business environments. The asymmetric effects can primarily be attributed to the asymmetric effects of monetary policy on discount rates across different monetary and business environments. We also observe that the impact of monetary policy on the returns of commercial banks is affected by bank-specific characteristics. Bank size, leverage and profitability play an important role in explaining the cross-sectional variation in bank returns as a result of monetary policy changes. We find that cross-sectional bank-specific characteristics affect the bank returns asymmetrically as a result of monetary policy changes across different business conditions. The results suggest that the effectiveness of monetary policy depends on the states of the economy.
{"title":"Effect of Monetary Policy on Commercial Banks Across Different Business Conditions","authors":"Syed M. Harun, M. Hassan, Tarek S. Zaher","doi":"10.17578/9-1/2-5","DOIUrl":"https://doi.org/10.17578/9-1/2-5","url":null,"abstract":"The objective of the paper is to investigate whether the stock price reactions of commercial banks to monetary policy actions are dependent on the state of the economy. The results indicate that monetary policy actions have asymmetric effects on the returns of commercial banks across different monetary policy and business environments. The asymmetric effects can primarily be attributed to the asymmetric effects of monetary policy on discount rates across different monetary and business environments. We also observe that the impact of monetary policy on the returns of commercial banks is affected by bank-specific characteristics. Bank size, leverage and profitability play an important role in explaining the cross-sectional variation in bank returns as a result of monetary policy changes. We find that cross-sectional bank-specific characteristics affect the bank returns asymmetrically as a result of monetary policy changes across different business conditions. The results suggest that the effectiveness of monetary policy depends on the states of the economy.","PeriodicalId":111923,"journal":{"name":"ERN: Monetary Policy (Topic)","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130807833","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}
During the recent financial crisis, emerging economies have kept accumulating both sovereign reserves and debt. To account for this empirical fact, we model the optimal portfolio choice of a sovereign that is subject to liquidity and productivity shocks. We determine the equilibrium level of debt and its cost by solving a contracting game between sovereign and international lenders. Although raising debt increases the sovereign exposure to liquidity and productivity crises, the simultaneous accumulation of reserves can mitigate the negative effects of such crises. This mechanism rationalizes the complementarity between debt and reserves.
{"title":"Sovereign Debt and Reserves with Liquidity and Productivity Crises","authors":"F. Corneli, E. Tarantino","doi":"10.2139/ssrn.2645715","DOIUrl":"https://doi.org/10.2139/ssrn.2645715","url":null,"abstract":"During the recent financial crisis, emerging economies have kept accumulating both sovereign reserves and debt. To account for this empirical fact, we model the optimal portfolio choice of a sovereign that is subject to liquidity and productivity shocks. We determine the equilibrium level of debt and its cost by solving a contracting game between sovereign and international lenders. Although raising debt increases the sovereign exposure to liquidity and productivity crises, the simultaneous accumulation of reserves can mitigate the negative effects of such crises. This mechanism rationalizes the complementarity between debt and reserves.","PeriodicalId":111923,"journal":{"name":"ERN: Monetary Policy (Topic)","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115781678","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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