The growth of cryptocurrency mining in China, still heavily reliant on coal as a fuel for electricity generation, raises natural questions on the inter-relatedness of coal and crypto prices and volatilities. We investigate this, and the safety and thus supply stability of domestic Chinese coal mining. We find strong evidence of increased bitcoin volatility in the period post-Chinese coal mining accidents, with limited effects on global coal prices. Global coal price interrelationships do not respond to Chinese mining disaster-induced volatility but do respond to the largest Bitcoin-related price movements.
{"title":"China, Coal, Calamities and Cryptos","authors":"Erdinç Akyıldırım, S. Corbet, B. Lucey","doi":"10.2139/ssrn.3851253","DOIUrl":"https://doi.org/10.2139/ssrn.3851253","url":null,"abstract":"The growth of cryptocurrency mining in China, still heavily reliant on coal as a fuel for electricity generation, raises natural questions on the inter-relatedness of coal and crypto prices and volatilities. We investigate this, and the safety and thus supply stability of domestic Chinese coal mining. We find strong evidence of increased bitcoin volatility in the period post-Chinese coal mining accidents, with limited effects on global coal prices. Global coal price interrelationships do not respond to Chinese mining disaster-induced volatility but do respond to the largest Bitcoin-related price movements.","PeriodicalId":7501,"journal":{"name":"Agricultural & Natural Resource Economics eJournal","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85860357","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 information would people like to have? What information would they prefer to avoid? How does the provision of information bear on welfare? And what does this mean for food policy? Representative surveys in eleven nations find that substantial percentages of people do not want to receive information even when it bears on health, sustainability, and consumer welfare. Nonetheless, substantial percentages of people also do want to receive that information, and people’s willingness to pay for information, contingent on their wanting it, is mostly higher than people’s willingness to pay not to receive information, contingent on their not wanting it. We develop a model and estimate the welfare effects of information provision. We find substantial benefits and costs, with the former outweighing the latter. The results suggest that in principle, policymakers should take both instrumental and hedonic effects into account when deciding whether to impose disclosure requirements for food, whether the domain involves health, safety, or moral considerations. If policymakers fail to consider either instrumental or hedonic effects, and if they fail to consider the magnitude of those effects, they will not capture the welfare consequences of disclosure requirements. Our evidence has concrete implications for how to think about, and capture, the welfare consequences of such requirements with respect to food.
{"title":"What Do People Want to Know? Information Avoidance and Food Policy Implications","authors":"C. Sunstein, L. Reisch, Micha Kaiser","doi":"10.2139/ssrn.3839513","DOIUrl":"https://doi.org/10.2139/ssrn.3839513","url":null,"abstract":"What information would people like to have? What information would they prefer to avoid? How does the provision of information bear on welfare? And what does this mean for food policy? Representative surveys in eleven nations find that substantial percentages of people do not want to receive information even when it bears on health, sustainability, and consumer welfare. Nonetheless, substantial percentages of people also do want to receive that information, and people’s willingness to pay for information, contingent on their wanting it, is mostly higher than people’s willingness to pay not to receive information, contingent on their not wanting it. We develop a model and estimate the welfare effects of information provision. We find substantial benefits and costs, with the former outweighing the latter. The results suggest that in principle, policymakers should take both instrumental and hedonic effects into account when deciding whether to impose disclosure requirements for food, whether the domain involves health, safety, or moral considerations. If policymakers fail to consider either instrumental or hedonic effects, and if they fail to consider the magnitude of those effects, they will not capture the welfare consequences of disclosure requirements. Our evidence has concrete implications for how to think about, and capture, the welfare consequences of such requirements with respect to food.<br>","PeriodicalId":7501,"journal":{"name":"Agricultural & Natural Resource Economics eJournal","volume":"60 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80537640","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 propose a static three-stage incentive-compatible, budget-balanced, execution-contingent scheme for a regulator to allocate biodiversity protection responsibilities across a landscape mosaic having multiple value-interdependent owners. The scheme motivates owners to truthfully report their opportunity costs of protection to the regulator and to comply with their assigned habitat protection responsibilities.
{"title":"Three-Stage TSARs, Interdependent Values, and Biodiversity Production on Private Lands","authors":"Mark D. Agee, T. Crocker","doi":"10.2139/ssrn.3883474","DOIUrl":"https://doi.org/10.2139/ssrn.3883474","url":null,"abstract":"We propose a static three-stage incentive-compatible, budget-balanced, execution-contingent scheme for a regulator to allocate biodiversity protection responsibilities across a landscape mosaic having multiple value-interdependent owners. The scheme motivates owners to truthfully report their opportunity costs of protection to the regulator and to comply with their assigned habitat protection responsibilities.","PeriodicalId":7501,"journal":{"name":"Agricultural & Natural Resource Economics eJournal","volume":"10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87162171","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}
Benson Z. Munar Benson Z. Munar, M. A. Estigoy, D. Vargas
The use of machinery has been adapted in various facets of agriculture as it helps to improve the farm practices of the farmers. Progressively higher levels of farm machinery have been introduced into all sectors of development, with the use of IEC materials (Information, Education, Campaign), farm machinery can be more effective. Philippine Center for Postharvest Development and Mechanization (PhilMech) is a government agency engaged in postharvest research, development, and extension activities. The scope of this study is not only awareness of IEC materials but also an increase in knowledge about farm machinery promoted through IEC materials. The respondents were purposively chosen. The agricultural office of San Jose identified the two (2) top rice-producing barangays in San Jose. They are 234 farmers that are randomly selected as respondents of the study. Farming is the main source of their income and the majority of the respondents are married and the common age of the respondents are ranging from 31 to 40 years old. The awareness level of farmers in farm machinery promoted through IEC materials in selected barangays of San Jose city is enough for the information they need. More farmers receive leaflets and flyers and some of the farmers are using the machinery that is promoted and developed by PhilMech.
{"title":"Awareness Level on Farm Machinery among Rice Farmers","authors":"Benson Z. Munar Benson Z. Munar, M. A. Estigoy, D. Vargas","doi":"10.2139/ssrn.3804325","DOIUrl":"https://doi.org/10.2139/ssrn.3804325","url":null,"abstract":"The use of machinery has been adapted in various facets of agriculture as it helps to improve the farm practices of the farmers. Progressively higher levels of farm machinery have been introduced into all sectors of development, with the use of IEC materials (Information, Education, Campaign), farm machinery can be more effective. Philippine Center for Postharvest Development and Mechanization (PhilMech) is a government agency engaged in postharvest research, development, and extension activities. The scope of this study is not only awareness of IEC materials but also an increase in knowledge about farm machinery promoted through IEC materials. The respondents were purposively chosen. The agricultural office of San Jose identified the two (2) top rice-producing barangays in San Jose. They are 234 farmers that are randomly selected as respondents of the study. Farming is the main source of their income and the majority of the respondents are married and the common age of the respondents are ranging from 31 to 40 years old. The awareness level of farmers in farm machinery promoted through IEC materials in selected barangays of San Jose city is enough for the information they need. More farmers receive leaflets and flyers and some of the farmers are using the machinery that is promoted and developed by PhilMech.","PeriodicalId":7501,"journal":{"name":"Agricultural & Natural Resource Economics eJournal","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85019304","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 paper analyzes optimal climate policy under uncertainty. It endows a recent quantitative analytic integrated assessment model (IAM) with long-run risk, adapting methods from the asset pricing literature to deal with endogenous climate risk. The model solves in closed-form for general degrees of risk aversion, stochastic climate feedbacks, and a stochastic damage-adaptation process. The model permits an exact solution of the infinite horizon stochastic fixed-point problem of a complex IAM. The approach facilitates new quantitative evidence for the role of uncertainty as well as analytic insights into the drivers and sensitivities of the optimal carbon tax facing an uncertain future.
{"title":"Uncertainty in the Analytic Climate Economy","authors":"Christian P. Traeger","doi":"10.2139/ssrn.3832735","DOIUrl":"https://doi.org/10.2139/ssrn.3832735","url":null,"abstract":"The paper analyzes optimal climate policy under uncertainty. It endows a recent quantitative analytic integrated assessment model (IAM) with long-run risk, adapting methods from the asset pricing literature to deal with endogenous climate risk. The model solves in closed-form for general degrees of risk aversion, stochastic climate feedbacks, and a stochastic damage-adaptation process. The model permits an exact solution of the infinite horizon stochastic fixed-point problem of a complex IAM. The approach facilitates new quantitative evidence for the role of uncertainty as well as analytic insights into the drivers and sensitivities of the optimal carbon tax facing an uncertain future.","PeriodicalId":7501,"journal":{"name":"Agricultural & Natural Resource Economics eJournal","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80086429","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 contend that economic preferences over risk-taking in different subnational regions worldwide affect fundamental aspects of firms’ corporate financing, namely financing costs and capital structure. We study this hypothesis, by hand-matching firms’ regions worldwide with the corresponding regional economic risk-taking preferences. Our baseline results show that credit and bond pricing increase with higher risk-taking preferences, whereas such preferences yield lower ratios of book leverage and short-term debt. We backup our baseline results with an instrumental variables approach, which is based on the premise that high-yield agricultural societies in the pre-industrial era exhibit low risk-taking preferences.
{"title":"Economic Preferences Over Risk-Taking and Corporate Finance","authors":"M. Delis, I. Hasan, C. Tsoumas, Maria Iosifidi","doi":"10.2139/ssrn.3794227","DOIUrl":"https://doi.org/10.2139/ssrn.3794227","url":null,"abstract":"We contend that economic preferences over risk-taking in different subnational regions worldwide affect fundamental aspects of firms’ corporate financing, namely financing costs and capital structure. We study this hypothesis, by hand-matching firms’ regions worldwide with the corresponding regional economic risk-taking preferences. Our baseline results show that credit and bond pricing increase with higher risk-taking preferences, whereas such preferences yield lower ratios of book leverage and short-term debt. We backup our baseline results with an instrumental variables approach, which is based on the premise that high-yield agricultural societies in the pre-industrial era exhibit low risk-taking preferences.","PeriodicalId":7501,"journal":{"name":"Agricultural & Natural Resource Economics eJournal","volume":"16 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86340349","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}
Humans globally have similar nutritional needs but face large differences in natural resource endowments and local food production. This study quantifies food system inequality across countries based on natural resource inputs, food/nutrient outputs, and nutrition/health outcomes, from 1970 to 2010. Animal source foods and overweight/obesity show rapid convergence while availability of selected micronutrients demonstrate slower convergence. However, all variables are more equally distributed than national income per capita, whose Gini coefficient declined from 0·71 to 0·65. Inequalities in total and animal-source dietary energy declined from 0·16 to 0·10 and 0·55 to 0·36, respectively. There was convergence in overweight/obesity prevalence from 0·39 to 0·27, while undernutrition and stunting became increasingly concentrated in a few high-burden countries. Characterizing cross-country inequalities in agricultural resources, foods, nutrients, and health can help identify critical opportunities for agriculture and food policies, as well as prioritize research objectives and funding allocation for the coming decade.
{"title":"Global dietary convergence from 1970 to 2010, despite inequality in agriculture, leaves undernutrition concentrated in a few countries","authors":"Winnie Bell, Keith Lividini, W. Masters","doi":"10.2139/ssrn.3638329","DOIUrl":"https://doi.org/10.2139/ssrn.3638329","url":null,"abstract":"Humans globally have similar nutritional needs but face large differences in natural resource endowments and local food production. This study quantifies food system inequality across countries based on natural resource inputs, food/nutrient outputs, and nutrition/health outcomes, from 1970 to 2010. Animal source foods and overweight/obesity show rapid convergence while availability of selected micronutrients demonstrate slower convergence. However, all variables are more equally distributed than national income per capita, whose Gini coefficient declined from 0·71 to 0·65. Inequalities in total and animal-source dietary energy declined from 0·16 to 0·10 and 0·55 to 0·36, respectively. There was convergence in overweight/obesity prevalence from 0·39 to 0·27, while undernutrition and stunting became increasingly concentrated in a few high-burden countries. Characterizing cross-country inequalities in agricultural resources, foods, nutrients, and health can help identify critical opportunities for agriculture and food policies, as well as prioritize research objectives and funding allocation for the coming decade.","PeriodicalId":7501,"journal":{"name":"Agricultural & Natural Resource Economics eJournal","volume":"57 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73858357","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 investigate the reliability of land measurement modes on non-classical measurement error and empirical relationships. In our multi-country survey experiment, we find significant differences between GPS and remotely sensed data only in Viet Nam, where plot sizes are small relative to the other countries. The magnitude of farmers’ self-reporting bias relative to GPS measures is nonlinear, with the largest magnitude of self-reporting bias of 130% of a standard deviation (2.2-hectare bias) in the Lao People’s Democratic Republic relative to Viet Nam, which has 13.3% of a standard deviation (.008-hectare bias). In all countries except Viet Nam, the inverse land size–productivity relationship is upwardly biased for lower land area self-reported measures relative to GPS measures. In Viet Nam, the intensive margin of organic fertilizer use is negatively biased (30.4 percentage points) by self-reported measurement error. We conclude by considering sources of measurement error in implementation and costs.
{"title":"Land Measurement Bias: Comparisons from Global Positioning System, Self-Reports, and Remote Sensing Data","authors":"A. Dillon, L. Rao","doi":"10.2139/ssrn.3801250","DOIUrl":"https://doi.org/10.2139/ssrn.3801250","url":null,"abstract":"We investigate the reliability of land measurement modes on non-classical measurement error and empirical relationships. In our multi-country survey experiment, we find significant differences between GPS and remotely sensed data only in Viet Nam, where plot sizes are small relative to the other countries. The magnitude of farmers’ self-reporting bias relative to GPS measures is nonlinear, with the largest magnitude of self-reporting bias of 130% of a standard deviation (2.2-hectare bias) in the Lao People’s Democratic Republic relative to Viet Nam, which has 13.3% of a standard deviation (.008-hectare bias). In all countries except Viet Nam, the inverse land size–productivity relationship is upwardly biased for lower land area self-reported measures relative to GPS measures. In Viet Nam, the intensive margin of organic fertilizer use is negatively biased (30.4 percentage points) by self-reported measurement error. We conclude by considering sources of measurement error in implementation and costs.","PeriodicalId":7501,"journal":{"name":"Agricultural & Natural Resource Economics eJournal","volume":"39 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74579716","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}
Policy-makers often seek to integrate markets as a way to maximize social welfare. Prior research has examined the effect of market integration on social welfare (surplus) only at two extremes -- when the markets are fully integrated, or, when they are fully isolated. But there is scarce information available for (i) how large the social surplus is at intermediate levels of market integration, and (ii) whether social surplus is maximized when markets are fully integrated, or fully isolated, or partially integrated. In this note, we consider the spectrum of all possible integration policies spanning from full isolation to complete integration, and characterize the socially-optimal market integration, under general demands. Our setting consists of a policy-maker, a price-setting firm, and a continuum of consumers in two markets. We identify market conditions under which social surplus is indeed maximized at partial market-integration. For the linear price-responsive demand model that is used extensively in the operations management literature, these conditions are identified as thresholds on (i) the relative size of the markets being integrated, and, (ii) the relative price-sensitivity of consumers in these markets. We then apply the model to the commercial seed market in European Union (EU). We first identify the optimal level of market integration between the markets for seed corn in various countries in EU. Subsequent analysis shows that socially-optimal market integration for these countries provides a further improvement in the social surplus for EU by 2.80%, relative to complete integration. Overall, our results show that policy-makers should exercise caution in determining the extent to which markets are integrated.
{"title":"Technical Note: Optimal Market Integration Decisions by Policy Makers: Modeling and Analysis of Agriculture Market Data","authors":"Shivam Gupta, S. Bansal","doi":"10.2139/ssrn.3628930","DOIUrl":"https://doi.org/10.2139/ssrn.3628930","url":null,"abstract":"Policy-makers often seek to integrate markets as a way to maximize social welfare. Prior research has examined the effect of market integration on social welfare (surplus) only at two extremes -- when the markets are fully integrated, or, when they are fully isolated. But there is scarce information available for (i) how large the social surplus is at intermediate levels of market integration, and (ii) whether social surplus is maximized when markets are fully integrated, or fully isolated, or partially integrated. In this note, we consider the spectrum of all possible integration policies spanning from full isolation to complete integration, and characterize the socially-optimal market integration, under general demands. Our setting consists of a policy-maker, a price-setting firm, and a continuum of consumers in two markets. We identify market conditions under which social surplus is indeed maximized at partial market-integration. For the linear price-responsive demand model that is used extensively in the operations management literature, these conditions are identified as thresholds on (i) the relative size of the markets being integrated, and, (ii) the relative price-sensitivity of consumers in these markets. We then apply the model to the commercial seed market in European Union (EU). We first identify the optimal level of market integration between the markets for seed corn in various countries in EU. Subsequent analysis shows that socially-optimal market integration for these countries provides a further improvement in the social surplus for EU by 2.80%, relative to complete integration. Overall, our results show that policy-makers should exercise caution in determining the extent to which markets are integrated.","PeriodicalId":7501,"journal":{"name":"Agricultural & Natural Resource Economics eJournal","volume":"72 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76481625","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}
Natalia Shagaida, Vasily Uzun, E. Gataulina, E. Shishkina
Russian abstract: Рассмотрены изменения в подходах к мониторингу продовольственной безопасности ФАО после принятия Целей устойчивого развития ООН до 2030 г., новации Доктрины продовольственной безопасности 2020 г, проведена по разным методикам оценка состояния и тенденций изменения продовольственной безопасности России с 2013 по 2019 г, а также – по доступным показателям – за 2020 г. English abstract: Changes in approaches of FAO food security monitoring after the adoption of the UN Sustainable Development Goals until 2030 and innovations in the 2020 RF Food Security Doctrine were considered. The assessment of the current state and trends in food security in Russia from 2013 to 2019 (by several available indicators - for 2020) was carried out using different methods.
{"title":"ОЦЕНКА СОСТОЯНИЯ ПРОДОВОЛЬСТВЕННОЙ БЕЗОПАСНОСТИ РОССИИ (Assessment of the State of Food Security in the Russia)","authors":"Natalia Shagaida, Vasily Uzun, E. Gataulina, E. Shishkina","doi":"10.2139/ssrn.3874900","DOIUrl":"https://doi.org/10.2139/ssrn.3874900","url":null,"abstract":"Russian abstract: Рассмотрены изменения в подходах к мониторингу продовольственной безопасности ФАО после принятия Целей устойчивого развития ООН до 2030 г., новации Доктрины продовольственной безопасности 2020 г, проведена по разным методикам оценка состояния и тенденций изменения продовольственной безопасности России с 2013 по 2019 г, а также – по доступным показателям – за 2020 г. English abstract: Changes in approaches of FAO food security monitoring after the adoption of the UN Sustainable Development Goals until 2030 and innovations in the 2020 RF Food Security Doctrine were considered. The assessment of the current state and trends in food security in Russia from 2013 to 2019 (by several available indicators - for 2020) was carried out using different methods.","PeriodicalId":7501,"journal":{"name":"Agricultural & Natural Resource Economics eJournal","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90113685","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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