Despite the ongoing appetite of financial investors for merchant investments into the European electricity network, the EC is reluctant to approve such undertakings, thus implicitly favoring regulated investments. Based on a two-level model, we analyze the impact of profit-maximizing merchant transmission investment as compared to welfare-maximizing regulated transmission investment. We apply the model to the Baltic Sea region, which has in the past been subject to rapid interconnector development and still would benefit from increased interconnection. We obtain stable results indicating that merchant investment may well contribute to overall welfare, but at the same time, “the merchant takes it all”, i.e. in many cases merchant profits are close to the overall efficiency gain, and sometimes even higher. These results underline that that distributional aspects, besides mere welfare arguments should be taken into account when analyzing the impact of merchant transmission investment.
{"title":"Is There Still a Case for Merchant Interconnectors? Insights from an Analysis of Welfare and Distributional Aspects of Options for Network Expansion in the Baltic Sea Region","authors":"Clemens Gerbaulet, Alexander Weber","doi":"10.2139/ssrn.2487759","DOIUrl":"https://doi.org/10.2139/ssrn.2487759","url":null,"abstract":"Despite the ongoing appetite of financial investors for merchant investments into the European electricity network, the EC is reluctant to approve such undertakings, thus implicitly favoring regulated investments. Based on a two-level model, we analyze the impact of profit-maximizing merchant transmission investment as compared to welfare-maximizing regulated transmission investment. We apply the model to the Baltic Sea region, which has in the past been subject to rapid interconnector development and still would benefit from increased interconnection. We obtain stable results indicating that merchant investment may well contribute to overall welfare, but at the same time, “the merchant takes it all”, i.e. in many cases merchant profits are close to the overall efficiency gain, and sometimes even higher. These results underline that that distributional aspects, besides mere welfare arguments should be taken into account when analyzing the impact of merchant transmission investment.","PeriodicalId":281108,"journal":{"name":"ERPN: Industrial Organization (Topic)","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130130968","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 assess the long-term financial returns from high-quality collectible real assets, and review the unique risks that are associated with such investments. Over the period 1900-2012, art, stamps, and musical instruments (violins) have appreciated at an average annual rate of 6.4%-6.9% in nominal terms, or 2.4%-2.8% in real terms. Despite the similarity in long-term returns, short-term trends can vary substantially across these different types of emotional assets. Collectibles have enjoyed higher average returns than government bonds, bills, and gold. However, it is important to recognize the quantitative importance of transaction costs in collectibles markets. In addition, price volatility is larger than is suggested by conventional measures of risk, and these assets are also exposed to fluctuating tastes and potential frauds. Yet, despite the large costs and many pitfalls, investment in emotional assets can pay off, because of the non-financial yield they provide.
{"title":"The Investment Performance of Art and Other Collectibles","authors":"E. Dimson, C. Spaenjers","doi":"10.2139/ssrn.2319338","DOIUrl":"https://doi.org/10.2139/ssrn.2319338","url":null,"abstract":"We assess the long-term financial returns from high-quality collectible real assets, and review the unique risks that are associated with such investments. Over the period 1900-2012, art, stamps, and musical instruments (violins) have appreciated at an average annual rate of 6.4%-6.9% in nominal terms, or 2.4%-2.8% in real terms. Despite the similarity in long-term returns, short-term trends can vary substantially across these different types of emotional assets. Collectibles have enjoyed higher average returns than government bonds, bills, and gold. However, it is important to recognize the quantitative importance of transaction costs in collectibles markets. In addition, price volatility is larger than is suggested by conventional measures of risk, and these assets are also exposed to fluctuating tastes and potential frauds. Yet, despite the large costs and many pitfalls, investment in emotional assets can pay off, because of the non-financial yield they provide.","PeriodicalId":281108,"journal":{"name":"ERPN: Industrial Organization (Topic)","volume":"477 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116907030","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 documents the extent and characteristics of plants and firms in the US that are outside the manufacturing sector according to official government statistics but nonetheless are heavily involved in activities related to the production of manufactured goods. Using new data on establishment activities in the Census of Wholesale Trade conducted by the US Bureau of the Census in 2002 and 2007, this paper provides evidence on so-called "factoryless goods producers" (FGPs) in the US economy. FGPs are formally in the wholesale sector but, unlike traditional wholesale establishments, FGPs design the goods they sell and coordinate the production activities. This paper documents the extent of FGPs in the wholesale sector and how they differ from traditional wholesalers in terms of their employment, wages, productivity and output. Reclassifying FGP establishments to the manufacturing sector using our definition would have shifted at least 595,000 workers to as many as 1,311,000 workers from wholesale to manufacturing sectors in 2002 and at least 431,000 workers to as many as 1,934,000 workers in 2007.
{"title":"Factoryless Goods Producers in the US","authors":"A. Bernard, Teresa C. Fort","doi":"10.2139/ssrn.2285677","DOIUrl":"https://doi.org/10.2139/ssrn.2285677","url":null,"abstract":"This paper documents the extent and characteristics of plants and firms in the US that are outside the manufacturing sector according to official government statistics but nonetheless are heavily involved in activities related to the production of manufactured goods. Using new data on establishment activities in the Census of Wholesale Trade conducted by the US Bureau of the Census in 2002 and 2007, this paper provides evidence on so-called \"factoryless goods producers\" (FGPs) in the US economy. FGPs are formally in the wholesale sector but, unlike traditional wholesale establishments, FGPs design the goods they sell and coordinate the production activities. This paper documents the extent of FGPs in the wholesale sector and how they differ from traditional wholesalers in terms of their employment, wages, productivity and output. Reclassifying FGP establishments to the manufacturing sector using our definition would have shifted at least 595,000 workers to as many as 1,311,000 workers from wholesale to manufacturing sectors in 2002 and at least 431,000 workers to as many as 1,934,000 workers in 2007.","PeriodicalId":281108,"journal":{"name":"ERPN: Industrial Organization (Topic)","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116838890","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}
Different types of products are procured in government procurement auctions. This paper empirically analyzes the effect of competition (number of bidders) on procurement price of different types of products. In other words, we investigate the optimal number of bidders which minimizes procurement costs in auctions for services, goods and construction. We use a unique data set provided by the Public Procurement Authority (PPA) of Turkey that covers all government procurement auctions for the years 2004-2009. This paper has three major results. First, after controlling for possible endogeneity, we show that the number of bidders significantly and negatively affects the procurement price. Thus, existence of a more competitive environment significantly decreases procurement costs in Turkey. Second, when auctions are open to foreign participation, the auction price tends to be lower. This is caused by an increase in the competitiveness of the auctions; detailed analysis of bidder participation to Turkish procurement auctions shows that number of bidders is significantly higher when auctions are open to foreign participation. Finally, the optimal number of bidders to take the full advantage of competition differs among auctions for different types of products. At least eight bidders are needed for services, seven for the goods sectors and at least thirteen bidders are required to be able to achieve the lowest procurement price possible for the construction auctions. The results of this paper has several policy implications for efficient procurement design.
{"title":"Procurement Efficiency in Public Procurement Auctions: Analysis of Different Types of Products","authors":"B. Tas","doi":"10.2139/ssrn.2148638","DOIUrl":"https://doi.org/10.2139/ssrn.2148638","url":null,"abstract":"Different types of products are procured in government procurement auctions. This paper empirically analyzes the effect of competition (number of bidders) on procurement price of different types of products. In other words, we investigate the optimal number of bidders which minimizes procurement costs in auctions for services, goods and construction. We use a unique data set provided by the Public Procurement Authority (PPA) of Turkey that covers all government procurement auctions for the years 2004-2009. This paper has three major results. First, after controlling for possible endogeneity, we show that the number of bidders significantly and negatively affects the procurement price. Thus, existence of a more competitive environment significantly decreases procurement costs in Turkey. Second, when auctions are open to foreign participation, the auction price tends to be lower. This is caused by an increase in the competitiveness of the auctions; detailed analysis of bidder participation to Turkish procurement auctions shows that number of bidders is significantly higher when auctions are open to foreign participation. Finally, the optimal number of bidders to take the full advantage of competition differs among auctions for different types of products. At least eight bidders are needed for services, seven for the goods sectors and at least thirteen bidders are required to be able to achieve the lowest procurement price possible for the construction auctions. The results of this paper has several policy implications for efficient procurement design.","PeriodicalId":281108,"journal":{"name":"ERPN: Industrial Organization (Topic)","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133864096","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 article constructs triple-difference tests around shifts in the supply of risk management instruments available to agricultural producers to reveal a positive relation between risk management and productivity. This relation is more robust when producers adopt instruments with payoffs linked to group performance and weaker when payoffs are linked to individual performance. Additionally, productivity is particularly high among risk-managing producers in counties containing high levels of bank deposits, a proxy for access to finance. Overall, this article illuminates the relation between hedging and real firm outcomes as well as the interaction between access to finance and firms' risk management choices.
{"title":"Does Risk Management Matter? Evidence from the U.S. Agricultural Industry","authors":"Jess Cornaggia","doi":"10.2139/ssrn.1314439","DOIUrl":"https://doi.org/10.2139/ssrn.1314439","url":null,"abstract":"This article constructs triple-difference tests around shifts in the supply of risk management instruments available to agricultural producers to reveal a positive relation between risk management and productivity. This relation is more robust when producers adopt instruments with payoffs linked to group performance and weaker when payoffs are linked to individual performance. Additionally, productivity is particularly high among risk-managing producers in counties containing high levels of bank deposits, a proxy for access to finance. Overall, this article illuminates the relation between hedging and real firm outcomes as well as the interaction between access to finance and firms' risk management choices.","PeriodicalId":281108,"journal":{"name":"ERPN: Industrial Organization (Topic)","volume":"327 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115873466","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}
David DesRoches, F. Potter, Betsy Santos, Ae Sengmavong, Yuhong Zheng
Although entrepreneurship is crucial to a capitalist economy, little information is available about U.S. businesses in their first years of operation. As part of an effort to gather more data on new businesses in the United States, the Ewing Marion Kauffman Foundation sponsored the Kauffman Firm Survey (KFS), a panel study of businesses founded in 2004 and tracked over their first years of operation. The KFS collects data about the nature of new business formation; the characteristics of the strategy, offerings, and employment patterns; the nature of the financial and organizational arrangements of these businesses; and the characteristics of those who own and operate them. With the completion of the Sixth Follow-Up Survey, the KFS has collected this information from the panel of diverse businesses over seven years, providing a unique look at business dynamics over this formative period.
尽管企业家精神对资本主义经济至关重要，但有关美国企业最初几年运营的信息却很少。为了收集更多关于美国新企业的数据，考夫曼基金会(Ewing Marion Kauffman Foundation)发起了考夫曼公司调查(KFS)，这是一项对2004年成立的企业进行的小组研究，并对它们运营的头几年进行跟踪。金融服务中心收集有关新业务性质的数据;战略、产品和就业模式的特点;这些业务的财务和组织安排的性质;以及拥有和经营它们的人的特点。随着第六次跟进调查的完成，金管局在过去七年里从不同行业的调查小组收集了这些信息，为这一形成时期的商业动态提供了一个独特的视角。
{"title":"Kauffman Firm Survey (KFS) Sixth Follow Up Methodology Report","authors":"David DesRoches, F. Potter, Betsy Santos, Ae Sengmavong, Yuhong Zheng","doi":"10.2139/ssrn.2027044","DOIUrl":"https://doi.org/10.2139/ssrn.2027044","url":null,"abstract":"Although entrepreneurship is crucial to a capitalist economy, little information is available about U.S. businesses in their first years of operation. As part of an effort to gather more data on new businesses in the United States, the Ewing Marion Kauffman Foundation sponsored the Kauffman Firm Survey (KFS), a panel study of businesses founded in 2004 and tracked over their first years of operation. The KFS collects data about the nature of new business formation; the characteristics of the strategy, offerings, and employment patterns; the nature of the financial and organizational arrangements of these businesses; and the characteristics of those who own and operate them. With the completion of the Sixth Follow-Up Survey, the KFS has collected this information from the panel of diverse businesses over seven years, providing a unique look at business dynamics over this formative period.","PeriodicalId":281108,"journal":{"name":"ERPN: Industrial Organization (Topic)","volume":"91 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124666593","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 Penn State Workforce Education and Development Initiative conducted an analysis of the economic impact of glass and glass products manufacturing in Huntingdon County in Pennsylvania. The analysis was designed to help understand the impact of the layoff of 77 employees at the AGY Products, Inc. plant in Huntingdon, Pennsylvania, effective April 3, 2010, that was announced on the Department of Labor and Industry's WARN notice website. AGY Products Inc., headquartered in Aiken, South Carolina, manufactures fiberglass yarns and reinforcements. The layoff generated considerable discussion in the community, which is documented in the Huntingdon County Alexandria Forum on topix.com.Products provided by AGY Products, Inc. are classified in the North American Industrial Classification System, code 32721. According to the U.S. Bureau of the Census, establishments in this industry "are primarily engaged in manufacturing glass and/or glass products. Establishments in this industry may manufacture glass and/or glass products by melting silica sand or cullet, or purchasing glass." During 2007, 97,876 workers were employed in 2,102 establishments in this industry throughout the U.S., with a payroll of $4.2 billion.
{"title":"Role of Glass & Glass Products Manufacturing in the Economy of Huntingdon County","authors":"R. Baker, Dawn Renee Dixon, D. Passmore","doi":"10.2139/SSRN.1587035","DOIUrl":"https://doi.org/10.2139/SSRN.1587035","url":null,"abstract":"The Penn State Workforce Education and Development Initiative conducted an analysis of the economic impact of glass and glass products manufacturing in Huntingdon County in Pennsylvania. The analysis was designed to help understand the impact of the layoff of 77 employees at the AGY Products, Inc. plant in Huntingdon, Pennsylvania, effective April 3, 2010, that was announced on the Department of Labor and Industry's WARN notice website. AGY Products Inc., headquartered in Aiken, South Carolina, manufactures fiberglass yarns and reinforcements. The layoff generated considerable discussion in the community, which is documented in the Huntingdon County Alexandria Forum on topix.com.Products provided by AGY Products, Inc. are classified in the North American Industrial Classification System, code 32721. According to the U.S. Bureau of the Census, establishments in this industry \"are primarily engaged in manufacturing glass and/or glass products. Establishments in this industry may manufacture glass and/or glass products by melting silica sand or cullet, or purchasing glass.\" During 2007, 97,876 workers were employed in 2,102 establishments in this industry throughout the U.S., with a payroll of $4.2 billion.","PeriodicalId":281108,"journal":{"name":"ERPN: Industrial Organization (Topic)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123904498","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}
There have been intense debates regarding which industrial sectors should be prioritized for receiving bailout in economic recessions. This paper takes a network perspective to rank sectors according to the Power-of-Pull (PoP), i.e. a sector's power to pull the overall economy. An eigenvector method is employed to assess the PoP of sectors in the USA, using input--output data from 1998 to 2010. The results support bailout to the motor vehicle sector, but argue against bailout to public infrastructure, health care and information technologies design and service sectors, and also reveal the continual decline of PoP ranking of computer and electronics manufacturing sector over time. These results confirm some but also show little support to some other economic revival policies of the Obama Administration in the USA.
{"title":"Which Industries to Bail Out First in Economic Recession? Ranking U.S. Industrial Sectors by the Power-of-Pull","authors":"Jianxi Luo","doi":"10.2139/SSRN.1430162","DOIUrl":"https://doi.org/10.2139/SSRN.1430162","url":null,"abstract":"There have been intense debates regarding which industrial sectors should be prioritized for receiving bailout in economic recessions. This paper takes a network perspective to rank sectors according to the Power-of-Pull (PoP), i.e. a sector's power to pull the overall economy. An eigenvector method is employed to assess the PoP of sectors in the USA, using input--output data from 1998 to 2010. The results support bailout to the motor vehicle sector, but argue against bailout to public infrastructure, health care and information technologies design and service sectors, and also reveal the continual decline of PoP ranking of computer and electronics manufacturing sector over time. These results confirm some but also show little support to some other economic revival policies of the Obama Administration in the USA.","PeriodicalId":281108,"journal":{"name":"ERPN: Industrial Organization (Topic)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115699835","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 study determinants of the probability of introducing an organizational innovation using three large cross sections of Italian manufacturing firms in the period 1995-2003. We analyze the effect and complementarity of other types of investments, like ICT, R&D, human and physical capital and the adoption of product or process innovations. Furthermore, we estimate the effect of introducing organizational innovations and indirectly technical innovations on the growth rate of labor productivity for the unbalanced panel of firms. Disembodied technological change is well represented by OIs, while product innovations seem to heve an effect on the efficiency of capital inputs only (capital stock-embodied technical change). Process innovations do not have a statistical impact as an indirect input-efficiency driving force, in our data.
{"title":"Organizational Innovations and Labor Productivity in a Panel of Italian Manufacturing Firms","authors":"F. Biagi, M. Parisi, Lucia Vergano","doi":"10.2139/ssrn.2526056","DOIUrl":"https://doi.org/10.2139/ssrn.2526056","url":null,"abstract":"We study determinants of the probability of introducing an organizational innovation using three large cross sections of Italian manufacturing firms in the period 1995-2003. We analyze the effect and complementarity of other types of investments, like ICT, R&D, human and physical capital and the adoption of product or process innovations. Furthermore, we estimate the effect of introducing organizational innovations and indirectly technical innovations on the growth rate of labor productivity for the unbalanced panel of firms. Disembodied technological change is well represented by OIs, while product innovations seem to heve an effect on the efficiency of capital inputs only (capital stock-embodied technical change). Process innovations do not have a statistical impact as an indirect input-efficiency driving force, in our data.","PeriodicalId":281108,"journal":{"name":"ERPN: Industrial Organization (Topic)","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116287343","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 market for pornography is of great economic relevance but has been totally ignored in economic investigation. The present paper focuses on the demand side of this market, with the main aim of proposing a preliminary theoretical assessment of the behavior of pornography purchasers. In this respect, certain contributions on hedonic adaptation have proved particularly useful, whereas models of addiction have proved less useful than might be expected. To link theoretical analysis more closely to reality, the first half of the paper describes the pornography industry in Italy, and may thus be considered a sort of case study.
{"title":"The Market for Pornography in Italy: Empirical Data and Theoretical Considerations","authors":"Fabio D’Orlando","doi":"10.2139/ssrn.1125129","DOIUrl":"https://doi.org/10.2139/ssrn.1125129","url":null,"abstract":"The market for pornography is of great economic relevance but has been totally ignored in economic investigation. The present paper focuses on the demand side of this market, with the main aim of proposing a preliminary theoretical assessment of the behavior of pornography purchasers. In this respect, certain contributions on hedonic adaptation have proved particularly useful, whereas models of addiction have proved less useful than might be expected. To link theoretical analysis more closely to reality, the first half of the paper describes the pornography industry in Italy, and may thus be considered a sort of case study.","PeriodicalId":281108,"journal":{"name":"ERPN: Industrial Organization (Topic)","volume":"30 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125697544","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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