Although improving agricultural productivity is vital to anti-poverty and food security goals, its ecological effects are theoretically ambiguous. Increasing the relative value of agricultural land may spur deforestation, but factor market constraints paired with improvements in existing land productivity may reduce the demand for shifting cultivation. Leveraging the discontinuity in eligibility for a large agricultural extension program, we find that the program reduced deforestation by 13%. The program increased adoption of promoted practices such as manure-use and crop rotation resulting in higher productivity but no increase in cultivated area. Suitably designed programs improving agricultural productivity may also enable conservation.
{"title":"Agriculture and Deforestation","authors":"Ryan Abman, Teevrat Garg, Yao Pan, S. Singhal","doi":"10.2139/ssrn.3692682","DOIUrl":"https://doi.org/10.2139/ssrn.3692682","url":null,"abstract":"Although improving agricultural productivity is vital to anti-poverty and food security goals, its ecological effects are theoretically ambiguous. Increasing the relative value of agricultural land may spur deforestation, but factor market constraints paired with improvements in existing land productivity may reduce the demand for shifting cultivation. Leveraging the discontinuity in eligibility for a large agricultural extension program, we find that the program reduced deforestation by 13%. The program increased adoption of promoted practices such as manure-use and crop rotation resulting in higher productivity but no increase in cultivated area. Suitably designed programs improving agricultural productivity may also enable conservation.","PeriodicalId":7501,"journal":{"name":"Agricultural & Natural Resource Economics eJournal","volume":"142 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75046645","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 the middle of the 19th century, the Kokand Khanate accelerated the process of specialization in agriculture, crafts, and trade among the population of cities and large villages, which made it possible to strengthen trade relations with neighboring countries. The conditions created for the development of trade relations with Russia were also discussed.
{"title":"Trade Relations between the Kokand Khanate and Russia","authors":"M. Karimova","doi":"10.2139/ssrn.3688544","DOIUrl":"https://doi.org/10.2139/ssrn.3688544","url":null,"abstract":"In the middle of the 19th century, the Kokand Khanate accelerated the process of specialization in agriculture, crafts, and trade among the population of cities and large villages, which made it possible to strengthen trade relations with neighboring countries. The conditions created for the development of trade relations with Russia were also discussed.","PeriodicalId":7501,"journal":{"name":"Agricultural & Natural Resource Economics eJournal","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75658384","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}
Oil booming and accumulated mineral revenue contributed to the economic growth in Azerbaijan since independence but also pressurized the national currency leading to the appreciation of the nominal effective exchange rate (NEER) and real effective exchange rate (REER). An increase in export prices makes them expensive, decreasing the competitiveness of the country. Azerbaijan’s recent decreased economic performance during 2014–2015 reflected a common reality among the resource exporting countries: relying on the primary sectors might jeopardize the national economy due to the extreme price volatility. The paper investigates the extension of the relationship between NEER, REER, and other export-related macroeconomic variables and agricultural exports to identify Azerbaijan’s non-oil sub-sectoral dynamics between 2001–2018 via the OLS estimations. The main findings indicate that NEER negatively impacted potato, fresh fruit, and fresh vegetable exports. Moreover, potato and fresh fruit exports demonstrated more stable export dynamics during the economic crisis periods.
{"title":"Determinants of the Agricultural Exports in Azerbaijan","authors":"I. Niftiyev","doi":"10.2139/ssrn.3686701","DOIUrl":"https://doi.org/10.2139/ssrn.3686701","url":null,"abstract":"Oil booming and accumulated mineral revenue contributed to the economic growth in Azerbaijan since independence but also pressurized the national currency leading to the appreciation of the nominal effective exchange rate (NEER) and real effective exchange rate (REER). An increase in export prices makes them expensive, decreasing the competitiveness of the country. Azerbaijan’s recent decreased economic performance during 2014–2015 reflected a common reality among the resource exporting countries: relying on the primary sectors might jeopardize the national economy due to the extreme price volatility. The paper investigates the extension of the relationship between NEER, REER, and other export-related macroeconomic variables and agricultural exports to identify Azerbaijan’s non-oil sub-sectoral dynamics between 2001–2018 via the OLS estimations. The main findings indicate that NEER negatively impacted potato, fresh fruit, and fresh vegetable exports. Moreover, potato and fresh fruit exports demonstrated more stable export dynamics during the economic crisis periods.","PeriodicalId":7501,"journal":{"name":"Agricultural & Natural Resource Economics eJournal","volume":"16 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82145236","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 assessed the external environment of the organic farming in Laguna Province, Philippines using Porter’s five forces framework. Using snow ball approach for the selection of participants, a total of 86 organic farmers in selected municipalities were included in the study. A self-made questionnaire was the main data gathering tool. Frequency distribution and percentage were used to analyze data. Majority of the organic farms were existing for 3 to 5 years, less than one hectare farm size, vegetable as the prime commodity and manual organic farming practices. Based on Porter’s five forces, threat of new entrants, threat of substitute and buyer power are high while supplier power and competitive rivalry are low. Results show that organic farming can be categorized as moderately attractive. Results suggest the need to intensify organic farming practices in the province of Laguna. The Porter’s Five Forces Analysis can be used for better organic farming outcomes and boost the industry to induce farmers to shift from conventional agriculture to organic farming.
{"title":"Porter’s Five Forces Analysis of the Organic Farming in Laguna Province","authors":"Marivic Abinsay","doi":"10.53378/345652","DOIUrl":"https://doi.org/10.53378/345652","url":null,"abstract":"This study assessed the external environment of the organic farming in Laguna Province, Philippines using Porter’s five forces framework. Using snow ball approach for the selection of participants, a total of 86 organic farmers in selected municipalities were included in the study. A self-made questionnaire was the main data gathering tool. Frequency distribution and percentage were used to analyze data. Majority of the organic farms were existing for 3 to 5 years, less than one hectare farm size, vegetable as the prime commodity and manual organic farming practices. Based on Porter’s five forces, threat of new entrants, threat of substitute and buyer power are high while supplier power and competitive rivalry are low. Results show that organic farming can be categorized as moderately attractive. Results suggest the need to intensify organic farming practices in the province of Laguna. The Porter’s Five Forces Analysis can be used for better organic farming outcomes and boost the industry to induce farmers to shift from conventional agriculture to organic farming.","PeriodicalId":7501,"journal":{"name":"Agricultural & Natural Resource Economics eJournal","volume":"43 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90539919","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}
Fernando Arteaga, Desiree A. Desierto, Mark Koyama
The trade route between Manila and Mexico was a monopoly of the Spanish Crown for more than 250 years. The Manila Galleons were “the richest ships in all the oceans”, but much of the wealth sank at sea and remain undiscovered. We introduce a newly constructed dataset of all of the ships that travelled this route. We show formally how monopoly rents that allowed widespread bribe-taking would have led to overloading and late ship departure, thereby increasing the probability of shipwreck. Empirically, we demonstrate not only that these late and overloaded ships were more likely to experience shipwrecks or to return to port, but that such effect is stronger for galleons carrying more valuable, higher-rent, cargo. This sheds new light on the costs of rent-seeking in European colonial empires.
{"title":"Shipwrecked by Rents","authors":"Fernando Arteaga, Desiree A. Desierto, Mark Koyama","doi":"10.2139/ssrn.3693463","DOIUrl":"https://doi.org/10.2139/ssrn.3693463","url":null,"abstract":"The trade route between Manila and Mexico was a monopoly of the Spanish Crown for more than 250 years. The Manila Galleons were “the richest ships in all the oceans”, but much of the wealth sank at sea and remain undiscovered. We introduce a newly constructed dataset of all of the ships that travelled this route. We show formally how monopoly rents that allowed widespread bribe-taking would have led to overloading and late ship departure, thereby increasing the probability of shipwreck. Empirically, we demonstrate not only that these late and overloaded ships were more likely to experience shipwrecks or to return to port, but that such effect is stronger for galleons carrying more valuable, higher-rent, cargo. This sheds new light on the costs of rent-seeking in European colonial empires.","PeriodicalId":7501,"journal":{"name":"Agricultural & Natural Resource Economics eJournal","volume":"105 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85891089","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}
Given the upward trend of OPEC energy intensity, policymakers need a good understanding of the underlying factors and the environmental impacts when considering future energy policies. An index decomposition analysis is used to decompose OPEC energy intensity covering 1971–2017. The link between the decomposed energy indices and CO emissions is examined using structural time series and least square dummy variable corrected models. Both models also estimate the underlying carbon emission trend (UCET) which arguably reflects the impact of non‐economic factors. For OPEC as a group, increases in energy intensity are linked to both energy inefficiency and structural shifts towards energy‐intensive activities. About 62 per cent of the increases are attributed to the former, and the remaining 38 per cent is due to the later. The country‐level results also show major contributions from both components to energy intensity. The econometric results show that shifts towards energy‐intensive activities and, notably, deteriorating energy efficiency generally go in tandem with substantial increases in CO emissions. The estimated UCET is upward sloping indicating carbon‐emitting behaviour, taste and lifestyle. Therefore, policies aimed at conserving energy and limiting the concentration of energy‐intensive activities in the oil‐exporting countries should be considered alongside other policies that attempt to influence behaviours and lifestyles.
{"title":"The Underlying Trend of OPEC Energy Intensity and the Environmental Implications","authors":"Ibrahim A. Tajudeen, A. Wossink","doi":"10.1111/opec.12183","DOIUrl":"https://doi.org/10.1111/opec.12183","url":null,"abstract":"Given the upward trend of OPEC energy intensity, policymakers need a good understanding of the underlying factors and the environmental impacts when considering future energy policies. An index decomposition analysis is used to decompose OPEC energy intensity covering 1971–2017. The link between the decomposed energy indices and CO emissions is examined using structural time series and least square dummy variable corrected models. Both models also estimate the underlying carbon emission trend (UCET) which arguably reflects the impact of non‐economic factors. For OPEC as a group, increases in energy intensity are linked to both energy inefficiency and structural shifts towards energy‐intensive activities. About 62 per cent of the increases are attributed to the former, and the remaining 38 per cent is due to the later. The country‐level results also show major contributions from both components to energy intensity. The econometric results show that shifts towards energy‐intensive activities and, notably, deteriorating energy efficiency generally go in tandem with substantial increases in CO emissions. The estimated UCET is upward sloping indicating carbon‐emitting behaviour, taste and lifestyle. Therefore, policies aimed at conserving energy and limiting the concentration of energy‐intensive activities in the oil‐exporting countries should be considered alongside other policies that attempt to influence behaviours and lifestyles.","PeriodicalId":7501,"journal":{"name":"Agricultural & Natural Resource Economics eJournal","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78764297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Natural and agricultural landscapes provide a wide range of ecosystem services, among which are aesthetic landscapes. As these services have no direct market value, land use decision makers often ignore them in favor of urban sprawl, resulting in suboptimal resource allocation. Here, we suggest a novel method to evaluate the aesthetic landscape services of natural and agricultural ecosystems using the case of the agritourism market in Israel. We model the agritourism market as an oligopolistic market with differentiated products and formulate an equilibrium model with structural, double nested logit demand and pricing equations. The structural equations are expressed as a function of the attributes of the agritourism firm, among which are the components of landscape view. We use aggregate market data and GIS data to estimate the structural model. In the case of urban sprawl, the welfare loss is estimated at US$29,000–53,000 per km2, depending on the type of ecosystem that is forgone, whereas in agricultural sprawl over natural areas, the welfare loss is estimated at US$38,000 per km2. This welfare loss can be considered the economic value of landscape aesthetics services to the agritourism market. These findings illustrate the potential of using this valuation method for other ecosystems in other markets.
{"title":"Economic Valuation of Cultural Ecosystem Services: The Case of Landscape Aesthetics in the Agritourism Market","authors":"Shachar Hatan, A. Fleischer, Anat Tchetchik","doi":"10.2139/ssrn.3679396","DOIUrl":"https://doi.org/10.2139/ssrn.3679396","url":null,"abstract":"Abstract Natural and agricultural landscapes provide a wide range of ecosystem services, among which are aesthetic landscapes. As these services have no direct market value, land use decision makers often ignore them in favor of urban sprawl, resulting in suboptimal resource allocation. Here, we suggest a novel method to evaluate the aesthetic landscape services of natural and agricultural ecosystems using the case of the agritourism market in Israel. We model the agritourism market as an oligopolistic market with differentiated products and formulate an equilibrium model with structural, double nested logit demand and pricing equations. The structural equations are expressed as a function of the attributes of the agritourism firm, among which are the components of landscape view. We use aggregate market data and GIS data to estimate the structural model. In the case of urban sprawl, the welfare loss is estimated at US$29,000–53,000 per km2, depending on the type of ecosystem that is forgone, whereas in agricultural sprawl over natural areas, the welfare loss is estimated at US$38,000 per km2. This welfare loss can be considered the economic value of landscape aesthetics services to the agritourism market. These findings illustrate the potential of using this valuation method for other ecosystems in other markets.","PeriodicalId":7501,"journal":{"name":"Agricultural & Natural Resource Economics eJournal","volume":"59 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73504174","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 Committee to Review Arrangements for Institutional Credit for Agriculture and Rural Development (CRAFICARD) was set up by RBI under the Chairmanship of Shri. B. Sivaraman. The Committee in its report submitted to RBI on November 28, 1979 recommended the establishment of NABARD. The Committee after reviewing the arrangements came to the conclusion that a new arrangement would be necessary at the national level for achieving the desired focus and thrust towards integration of credit activities in the context of the strategy for Integrated Rural Development. Against the backdrop of the huge credit needs of rural development and the need to uplift the weaker sections in the rural areas within a given time horizon the arrangement called for a separate institutional set-up. Similarly. The Reserve Bank had onerous responsibilities to discharge in respect of its many basic functions of central banking in monetary and credit regulations and was not therefore in a position to devote undivided attention to the operational details of the emerging complex credit problems. This cemented the way for the establishment of NABARD.
{"title":"NABARD Vis-À-Vis Strategic Development Program in India","authors":"Sankalp Jain","doi":"10.2139/ssrn.3902339","DOIUrl":"https://doi.org/10.2139/ssrn.3902339","url":null,"abstract":"The Committee to Review Arrangements for Institutional Credit for Agriculture and Rural Development (CRAFICARD) was set up by RBI under the Chairmanship of Shri. B. Sivaraman. The Committee in its report submitted to RBI on November 28, 1979 recommended the establishment of NABARD. The Committee after reviewing the arrangements came to the conclusion that a new arrangement would be necessary at the national level for achieving the desired focus and thrust towards integration of credit activities in the context of the strategy for Integrated Rural Development. Against the backdrop of the huge credit needs of rural development and the need to uplift the weaker sections in the rural areas within a given time horizon the arrangement called for a separate institutional set-up. Similarly. The Reserve Bank had onerous responsibilities to discharge in respect of its many basic functions of central banking in monetary and credit regulations and was not therefore in a position to devote undivided attention to the operational details of the emerging complex credit problems. This cemented the way for the establishment of NABARD.","PeriodicalId":7501,"journal":{"name":"Agricultural & Natural Resource Economics eJournal","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76741045","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}
Incentive-based conservation is a promising approach to tropical forest conservation, including within multiple-use protected areas. In this paper, we analyze the environmental impacts of Bolsa Floresta, a longstanding forest conservation program combining conditional household–level payments with livelihood-focused investments in 15 multiple-use forest reserve areas in the Brazilian state of Amazonas. We use grid-based data, nearest-neighbor matching, and panel data econometrics to compare three forest-related program outcomes – deforestation, degradation, and fires – of participating and non-participating reserve areas. Both pre and post-treatment deforestation and degradation pressures were low, including because low–pressure sites had been preferentially targeted. Thus, we find significant but small additional conservation effects from the implementation of the program. Notwithstanding, treatment effects excel in areas with higher deforestation pressure and higher potential agricultural income. Our findings add to the growing body of evidence showing that adverse spatial targeting by administrative choice, i.e. dis- proportionally selecting low–pressure sites into programs, is a prime cause for the low additionality found in rigorous impact evaluations of incentive-based forest conservation initiatives.
{"title":"Impacts of Conservation Incentives in Protected Areas: The Case of Bolsa Floresta, Brazil","authors":"E. Cisneros, J. Börner, S. Pagiola, S. Wunder","doi":"10.2139/ssrn.3676708","DOIUrl":"https://doi.org/10.2139/ssrn.3676708","url":null,"abstract":"Incentive-based conservation is a promising approach to tropical forest conservation, including within multiple-use protected areas. In this paper, we analyze the environmental impacts of Bolsa Floresta, a longstanding forest conservation program combining conditional household–level payments with livelihood-focused investments in 15 multiple-use forest reserve areas in the Brazilian state of Amazonas. We use grid-based data, nearest-neighbor matching, and panel data econometrics to compare three forest-related program outcomes – deforestation, degradation, and fires – of participating and non-participating reserve areas. Both pre and post-treatment deforestation and degradation pressures were low, including because low–pressure sites had been preferentially targeted. Thus, we find significant but small additional conservation effects from the implementation of the program. Notwithstanding, treatment effects excel in areas with higher deforestation pressure and higher potential agricultural income. Our findings add to the growing body of evidence showing that adverse spatial targeting by administrative choice, i.e. dis- proportionally selecting low–pressure sites into programs, is a prime cause for the low additionality found in rigorous impact evaluations of incentive-based forest conservation initiatives.","PeriodicalId":7501,"journal":{"name":"Agricultural & Natural Resource Economics eJournal","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87486860","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 proxy Global Real Economic Activity with the cost of shipping 6 major commodities: crude oil, natural gas, coal, grain, container & airplane parcel. We show that the business cycle decomposition of this newly called BiB indicator tracks very well the business cycle inferred from the world industrial production index (WIP). In a nowcasting exercise, we prove BiB to anticipate WIP one month ahead with a notable gain wrt. a drift less random walk. Our index outperforms the GREA proxy proposed by Kilian (coal shipping cost) as well as the ADS index from the US FED. Additionally, we compute the long run real cost, in $ per ton, for shipping our 6 major commodities together with their opportunity cost over recent decades (share of total import cost eaten up by transportation).
{"title":"Ocean Shipping Cost as a proxy of Real Economic Activity","authors":"Nicolas Boccard","doi":"10.2139/ssrn.3675666","DOIUrl":"https://doi.org/10.2139/ssrn.3675666","url":null,"abstract":"We proxy Global Real Economic Activity with the cost of shipping 6 major commodities: crude oil, natural gas, coal, grain, container & airplane parcel. We show that the business cycle decomposition of this newly called BiB indicator tracks very well the business cycle inferred from the world industrial production index (WIP). In a nowcasting exercise, we prove BiB to anticipate WIP one month ahead with a notable gain wrt. a drift less random walk. Our index outperforms the GREA proxy proposed by Kilian (coal shipping cost) as well as the ADS index from the US FED. Additionally, we compute the long run real cost, in $ per ton, for shipping our 6 major commodities together with their opportunity cost over recent decades (share of total import cost eaten up by transportation).","PeriodicalId":7501,"journal":{"name":"Agricultural & Natural Resource Economics eJournal","volume":"126 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77824458","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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