The modern law of induced patent infringement contradicts the Patent Act and violates the First Amendment. As currently applied, the law unconstitutionally restricts speech, discourages the entry of generic drugs, and helps keep medicine prices high. Under current doctrine, a generic drugmaker is liable for induced infringement if its drug label so much as hints at using a product in a way that is covered by a patent. This is true even when there is no evidence that prescribers read generic drug labels and in cases when only an in-depth inquiry into the language of the label might promote infringement. As I show, this doctrine flies in the face of a simple reading of the statute. And by restricting lawful and non-misleading speech for such an attenuated purpose, it also violates the First Amendment. Modern patent inducement law should be revised because it unconstitutionally prolongs drug monopolies and undermines a key statutory path to generic competition. Revisiting the roots of inducement doctrine also leads to the surprising conclusion that method-of-use patents—a cornerstone of pharmaceutical intellectual property—are weaker than generally supposed.
{"title":"Speech, Drugs, and Patent Infringement","authors":"D. Bloomfield","doi":"10.2139/SSRN.3744403","DOIUrl":"https://doi.org/10.2139/SSRN.3744403","url":null,"abstract":"The modern law of induced patent infringement contradicts the Patent Act and violates the First Amendment. As currently applied, the law unconstitutionally restricts speech, discourages the entry of generic drugs, and helps keep medicine prices high. \u0000 \u0000Under current doctrine, a generic drugmaker is liable for induced infringement if its drug label so much as hints at using a product in a way that is covered by a patent. This is true even when there is no evidence that prescribers read generic drug labels and in cases when only an in-depth inquiry into the language of the label might promote infringement. As I show, this doctrine flies in the face of a simple reading of the statute. And by restricting lawful and non-misleading speech for such an attenuated purpose, it also violates the First Amendment. \u0000 \u0000Modern patent inducement law should be revised because it unconstitutionally prolongs drug monopolies and undermines a key statutory path to generic competition. Revisiting the roots of inducement doctrine also leads to the surprising conclusion that method-of-use patents—a cornerstone of pharmaceutical intellectual property—are weaker than generally supposed.","PeriodicalId":14586,"journal":{"name":"IO: Productivity","volume":"37 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86860956","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}
Cyril Verluise, G. Cristelli, Kyle W. Higham, Gaétan de Rassenfosse
Patent citations are one of the most commonly-used metrics in the innovation literature. Leading uses of patent-to-patent citations are associated with the quantification of inventions' quality and the measurement of knowledgeflows. Due to their widespread availability, scholars have exploited citations listed on the front-page of patent documents. Citations appearing in the full-text of patent documents have been neglected. We apply modern machine learning methods to extract these citations from the text of USPTO patent documents. Overall, we are able to recover an additional 15 percent of patent citations that could not be found using only front-page data. We show that "in-text" citations bring a different type of information compared to front-page citations. They exhibit higher text-similarity to the citing patents and alter the ranking of patent importance. The dataset is available at patcit.io (CC-BY-4).
{"title":"The Missing 15 Percent of Patent Citations","authors":"Cyril Verluise, G. Cristelli, Kyle W. Higham, Gaétan de Rassenfosse","doi":"10.2139/ssrn.3754772","DOIUrl":"https://doi.org/10.2139/ssrn.3754772","url":null,"abstract":"Patent citations are one of the most commonly-used metrics in the innovation literature. Leading uses of patent-to-patent citations are associated with the quantification of inventions' quality and the measurement of knowledgeflows. Due to their widespread availability, scholars have exploited citations listed on the front-page of patent documents. Citations appearing in the full-text of patent documents have been neglected. We apply modern machine learning methods to extract these citations from the text of USPTO patent documents. Overall, we are able to recover an additional 15 percent of patent citations that could not be found using only front-page data. We show that \"in-text\" citations bring a different type of information compared to front-page citations. They exhibit higher text-similarity to the citing patents and alter the ranking of patent importance. The dataset is available at patcit.io (CC-BY-4).","PeriodicalId":14586,"journal":{"name":"IO: Productivity","volume":"116 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87819171","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}
In a recent paper, Bloom et al. (2020) find evidence for a substantial decline in research productivity in the U.S. economy during the last 40 years. In this paper, we replicate their findings for China and Germany, using detailed firm-level data spanning three decades. Our results indicate that diminishing returns in idea production are a global phenomenon, not just confined to the U.S.
{"title":"A Global Decline in Research Productivity? Evidence from China and Germany","authors":"Paul Hünermund, P. Boeing","doi":"10.2139/ssrn.3644168","DOIUrl":"https://doi.org/10.2139/ssrn.3644168","url":null,"abstract":"In a recent paper, Bloom et al. (2020) find evidence for a substantial decline in research productivity in the U.S. economy during the last 40 years. In this paper, we replicate their findings for China and Germany, using detailed firm-level data spanning three decades. Our results indicate that diminishing returns in idea production are a global phenomenon, not just confined to the U.S.","PeriodicalId":14586,"journal":{"name":"IO: Productivity","volume":"33 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79032740","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}
Although there are many versions of blockchain technology today, it was first introduced in 2008 as the technology supporting Bitcoin, the first successful virtual currency system. Yet in and of itself, Blockchain technology is much more than the underpinning for Bitcoin (and other cryptocurrencies) and has found many applications beyond its initial purpose. The goal of this advanced primer is to review the current state of this technology and to discuss some of its advantages and drawbacks in settings beyond crypto-currencies.
{"title":"Blockchain and Other Distributed Ledger Technologies, An Advanced Primer","authors":"G. Hilary","doi":"10.2139/ssrn.3740067","DOIUrl":"https://doi.org/10.2139/ssrn.3740067","url":null,"abstract":"Although there are many versions of blockchain technology today, it was first introduced in 2008 as the technology supporting Bitcoin, the first successful virtual currency system. Yet in and of itself, Blockchain technology is much more than the underpinning for Bitcoin (and other cryptocurrencies) and has found many applications beyond its initial purpose. The goal of this advanced primer is to review the current state of this technology and to discuss some of its advantages and drawbacks in settings beyond crypto-currencies.","PeriodicalId":14586,"journal":{"name":"IO: Productivity","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87597128","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 chapter brings new evidence on the relationship between short-term labour mobility, as proxied by tourism flows, and innovation in Africa. Using data from 34 African countries over the period 2011-2016 sourced from the World Bank’s Enterprise Survey, we find that short–term mobility positively contributes to innovation, making this a potentially effective channel for economic development alongside established determinants such as investments in R&D, foreign direct investments, and trade. Short-term labour mobility thus emerges in Africa, too, as a prospective policy lever to generate new productive knowledge and promote sustainable economic growth.
{"title":"Migration, Innovation, and Growth: An African Story?","authors":"L. Mbaye, M. Tani","doi":"10.4324/9780429288814-4","DOIUrl":"https://doi.org/10.4324/9780429288814-4","url":null,"abstract":"This chapter brings new evidence on the relationship between short-term labour mobility, as proxied by tourism flows, and innovation in Africa. Using data from 34 African countries over the period 2011-2016 sourced from the World Bank’s Enterprise Survey, we find that short–term mobility positively contributes to innovation, making this a potentially effective channel for economic development alongside established determinants such as investments in R&D, foreign direct investments, and trade. Short-term labour mobility thus emerges in Africa, too, as a prospective policy lever to generate new productive knowledge and promote sustainable economic growth.","PeriodicalId":14586,"journal":{"name":"IO: Productivity","volume":"13 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87913069","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 emergence of blockchain, other distributed ledger technologies (‘DLT’) and the potential of asset tokenization has led to a lot of attention in the past three years. Despite ‘ICO scams’ in 2017 and 2018, the use of DLT-based tokens in financial markets has nevertheless kept growing, and asset tokenization has become one of the most prominent use-cases of DLTs in the financial markets. Tokenized assets includes securities (e.g. stocks and bonds), but also commodities (e.g. gold) and other non-financial assets (e.g. real estate). Asset tokenization has potential cross-cutting implications for financial market practices and participants, market infrastructures and regulators across a large range of financial instruments and asset classes.
Given the above, a discussion on the potential implications of asset tokenization and DLT in general for European investment funds is warranted. Increased use of DLT and asset tokenization could have widespread potential benefits in terms of cost and speed efficiencies, increased transparency and liquidity. Although the use of DLT and tokenization in (European) investment funds is currently limited, its potential is significant. Careful consideration of the possible impact of DLT and the use of asset tokenization in the field of (European) investment funds will allow policy makers to anticipate potential perils linked to the wider use of DLT by (European) investment funds.
This contribution provides a high-level overview of the use of DLT and asset tokenization for (European investment funds). It starts by giving a concise overview of European investment fund law in general. In particular, Section 2 explains the law and economics of European fund governance consisting of a tripartite relationship between fund managers, depositaries and investors. It continues to explain in Section 3 that, currently, the application of DLT has to be seen as a natural evolution of European investment funds and its legal framework; and not as disruption thereof. Section 4 touches upon the to be expected impact of DLT and asset tokenization on fund managers. It analyzes in detail the impact of DLT on the tasks of fund managers under the AIFMD and UCITSD consisting of (i) investment management, (ii) administration and (iii) marketing. Section 5 discusses the restrictions of European investment fund investing in tokenized assets set by European and national eligible asset requirements (i.e. ‘product regulation’). Section 6 discusses the impact of DLT and tokenized assets on AIFMD and UCITSD depositaries, Section 7 discusses the to be expected impacts of DLT on (European) investment funds on the short, medium and long-term and Section 8 concludes.
{"title":"Distributed Ledger Technology (‘DLT’) and its Impact (on the Regulation of) European Investment Funds","authors":"Sebastiaan Niels Hooghiemstra","doi":"10.2139/ssrn.3735886","DOIUrl":"https://doi.org/10.2139/ssrn.3735886","url":null,"abstract":"The emergence of blockchain, other distributed ledger technologies (‘DLT’) and the potential of asset tokenization has led to a lot of attention in the past three years. Despite ‘ICO scams’ in 2017 and 2018, the use of DLT-based tokens in financial markets has nevertheless kept growing, and asset tokenization has become one of the most prominent use-cases of DLTs in the financial markets. Tokenized assets includes securities (e.g. stocks and bonds), but also commodities (e.g. gold) and other non-financial assets (e.g. real estate). Asset tokenization has potential cross-cutting implications for financial market practices and participants, market infrastructures and regulators across a large range of financial instruments and asset classes.<br><br>Given the above, a discussion on the potential implications of asset tokenization and DLT in general for European investment funds is warranted. Increased use of DLT and asset tokenization could have widespread potential benefits in terms of cost and speed efficiencies, increased transparency and liquidity. Although the use of DLT and tokenization in (European) investment funds is currently limited, its potential is significant. Careful consideration of the possible impact of DLT and the use of asset tokenization in the field of (European) investment funds will allow policy makers to anticipate potential perils linked to the wider use of DLT by (European) investment funds.<br><br>This contribution provides a high-level overview of the use of DLT and asset tokenization for (European investment funds). It starts by giving a concise overview of European investment fund law in general. In particular, Section 2 explains the law and economics of European fund governance consisting of a tripartite relationship between fund managers, depositaries and investors. It continues to explain in Section 3 that, currently, the application of DLT has to be seen as a natural evolution of European investment funds and its legal framework; and not as disruption thereof. Section 4 touches upon the to be expected impact of DLT and asset tokenization on fund managers. It analyzes in detail the impact of DLT on the tasks of fund managers under the AIFMD and UCITSD consisting of (i) investment management, (ii) administration and (iii) marketing. Section 5 discusses the restrictions of European investment fund investing in tokenized assets set by European and national eligible asset requirements (i.e. ‘product regulation’). Section 6 discusses the impact of DLT and tokenized assets on AIFMD and UCITSD depositaries, Section 7 discusses the to be expected impacts of DLT on (European) investment funds on the short, medium and long-term and Section 8 concludes.","PeriodicalId":14586,"journal":{"name":"IO: Productivity","volume":"38 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76905805","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}
In this paper, we study platform solutions for improving customer engagement in online higher education by reducing informational inequality for historically under-represented groups in education such as females and workers seeking to improve their skill set. Using novel search and enrollment data from the largest online education platform in Iran, we estimate a structural model of course search and enrollment for paid courses, allowing us to recover learner belief's about courses, as well as their true preference over the characteristic space of online courses. We use machine learning methods to recover the latent characteristic space of courses, identifying which courses are substitutes via a data-driven approach. We document significant heterogeneity in how learners differing by gender and working status perceive course value, due to biased beliefs, relative to the true value. Counterfactual policy exercises suggest that the platform can increase revenue, improve consumer surplus, and reduce the gender gap in quantitative courses. Finally, we also present the problem faced by the platform from an information design perspective, and characterize the optimal signal the platform can send to learners with heterogenous priors to maximize an arbitrary objective function.
{"title":"Information Inequality in Online Education","authors":"Luis Armona, M. Rasouli","doi":"10.2139/ssrn.3730109","DOIUrl":"https://doi.org/10.2139/ssrn.3730109","url":null,"abstract":"In this paper, we study platform solutions for improving customer engagement in online higher education by reducing informational inequality for historically under-represented groups in education such as females and workers seeking to improve their skill set. \u0000Using novel search and enrollment data from the largest online education platform in Iran, we estimate a structural model of course search and enrollment for paid courses, allowing us to recover learner belief's about courses, as well as their true preference over the characteristic space of online courses. We use machine learning methods to recover the latent characteristic space of courses, identifying which courses are substitutes via a data-driven approach. \u0000We document significant heterogeneity in how learners differing by gender and working status perceive course value, due to biased beliefs, relative to the true value. Counterfactual policy exercises suggest that the platform can increase revenue, improve consumer surplus, and reduce the gender gap in quantitative courses. Finally, we also present the problem faced by the platform from an information design perspective, and characterize the optimal signal the platform can send to learners with heterogenous priors to maximize an arbitrary objective function.","PeriodicalId":14586,"journal":{"name":"IO: Productivity","volume":"39 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76944665","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 study investigates whether and how financial technologies (FinTech) influence the effectiveness of monetary policy transmission. We use an interacted panel vector autoregression model to explore how the effects of monetary policy shocks change with regional-level FinTech adoption. Results indicate that FinTech adoption generally mitigates monetary policy transmission to real GDP, consumer prices, bank loans, and housing prices. A subcategorical analysis shows that the muted transmission is the most pronounced in the adoption of FinTech payment and credit, compared to that of insurance. The regulatory arbitrage and competition between FinTech and banks are the possible mechanisms leading to a mitigated monetary policy transmission.
{"title":"Financial Technologies and the Effectiveness of Monetary Policy Transmission","authors":"I. Hasan, Boreum Kwak, Xiang Li","doi":"10.2139/ssrn.3743203","DOIUrl":"https://doi.org/10.2139/ssrn.3743203","url":null,"abstract":"This study investigates whether and how financial technologies (FinTech) influence the effectiveness of monetary policy transmission. We use an interacted panel vector autoregression model to explore how the effects of monetary policy shocks change with regional-level FinTech adoption. Results indicate that FinTech adoption generally mitigates monetary policy transmission to real GDP, consumer prices, bank loans, and housing prices. A subcategorical analysis shows that the muted transmission is the most pronounced in the adoption of FinTech payment and credit, compared to that of insurance. The regulatory arbitrage and competition between FinTech and banks are the possible mechanisms leading to a mitigated monetary policy transmission.","PeriodicalId":14586,"journal":{"name":"IO: Productivity","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91530811","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}
Shocks transmitted from productivity leaders to lagging economies are systematic sources of risk. Global technology and knowledge diffusion leads to predictable patterns in productivity dynamics across countries and industries. Technology gaps determine the level of exposure to the systematic productivity shocks. Firms in a country-industry with larger technology gaps relative to the world leader are more dependent on the leader’s innovations compared to their own productivity improvements. They thus have higher loadings on the leader productivity shocks and higher average stock returns. For OECD panel data, a country-industry’s technology gap significantly predicts the stock returns of the country-industry: holding the quintile of country-industry portfolios with the largest gaps and shorting the quintile with the smallest gaps generates annual returns of 9.8% (6.7% after risk adjustment with standard factors). A factor representing the technological productivity gap explains country-industry portfolio returns substantially better than standard factor models. Loadings on leader-country productivity shocks have substantial correlation with technology gaps, and leader productivity shocks are more important for stock returns than idiosyncratic productivity shocks. These findings support that the technology gaps and associated higher average returns are indeed linked to systematic risk.
{"title":"Productivity Gaps and Global Systematic Risk Exposure: Pricing Country-Industry Portfolios","authors":"Punit Anand, Ronald J. Balvers","doi":"10.2139/ssrn.3663430","DOIUrl":"https://doi.org/10.2139/ssrn.3663430","url":null,"abstract":"Shocks transmitted from productivity leaders to lagging economies are systematic sources of risk. Global technology and knowledge diffusion leads to predictable patterns in productivity dynamics across countries and industries. Technology gaps determine the level of exposure to the systematic productivity shocks. Firms in a country-industry with larger technology gaps relative to the world leader are more dependent on the leader’s innovations compared to their own productivity improvements. They thus have higher loadings on the leader productivity shocks and higher average stock returns. For OECD panel data, a country-industry’s technology gap significantly predicts the stock returns of the country-industry: holding the quintile of country-industry portfolios with the largest gaps and shorting the quintile with the smallest gaps generates annual returns of 9.8% (6.7% after risk adjustment with standard factors). A factor representing the technological productivity gap explains country-industry portfolio returns substantially better than standard factor models. Loadings on leader-country productivity shocks have substantial correlation with technology gaps, and leader productivity shocks are more important for stock returns than idiosyncratic productivity shocks. These findings support that the technology gaps and associated higher average returns are indeed linked to systematic risk.","PeriodicalId":14586,"journal":{"name":"IO: Productivity","volume":"60 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80974380","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 studies the difference in task supplies and economic status between natives and two generations of immigrants. I estimate differences in task supply and earnings between natives and immigrants in 1970 and 2015, which are the beginning and end of the fifth (and current) wave of immigration to Canada. Furthermore, using a three-fold Blinder-Oaxaca decomposition, I link the average weekly wage of workers to their task productivity, and try to find the effects of the returns to tasks as well as different task supplies on the average wage gap between natives and immigrants. Finally, I use ordered probit and logit models to demonstrate and measure the significant effects of immigrant status on an employee's labor market segment.
{"title":"Task Supply, Wage Earning, and Segmentation among Natives and Two Generations of Immigrants","authors":"Shiyu Jiang","doi":"10.2139/ssrn.3723217","DOIUrl":"https://doi.org/10.2139/ssrn.3723217","url":null,"abstract":"This paper studies the difference in task supplies and economic status between natives and two generations of immigrants. I estimate differences in task supply and earnings between natives and immigrants in 1970 and 2015, which are the beginning and end of the fifth (and current) wave of immigration to Canada. Furthermore, using a three-fold Blinder-Oaxaca decomposition, I link the average weekly wage of workers to their task productivity, and try to find the effects of the returns to tasks as well as different task supplies on the average wage gap between natives and immigrants. Finally, I use ordered probit and logit models to demonstrate and measure the significant effects of immigrant status on an employee's labor market segment.","PeriodicalId":14586,"journal":{"name":"IO: Productivity","volume":"16 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80932854","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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